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Sample records for halophilic microorganisms isolated

  1. Progress in decontamination by halophilic microorganisms in saline wastewater and soil

    International Nuclear Information System (INIS)

    Zhuang Xuliang; Han Zhen; Bai Zhihui; Zhuang Guoqiang; Shim Hojae

    2010-01-01

    Environments with high-salt concentrations are often populated by dense microbial communities. Halophilic microorganisms can be isolated from different saline environments and different strains even belonging to the same genus have various applications. Wastewater and soil rich in both organic matter and salt are difficult to treat using conventional microorganisms typically found in wastewater treatment and soil bioremediation facilities. Studies on decontaminative capabilities and decontamination pathways of organic contaminants (i.e., aromatic compounds benzoate, cinnamate, 3-phenylpropionate, 4-hydroxybenzoic acid), heavy metals (i.e., tellurium, vanadium), and nutrients in the biological treatment of saline wastewater and soil by halophilic microorganisms are discussed in this review. - Review on the decontaminative capabilities of halophilic microorganisms in saline wastewater and soil.

  2. Progress in decontamination by halophilic microorganisms in saline wastewater and soil

    Energy Technology Data Exchange (ETDEWEB)

    Zhuang Xuliang, E-mail: xlzhuang@rcees.ac.c [Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing 100085 (China); Bureau of Science and Technology for Resources and Environment, Chinese Academy of Sciences, Beijing 100864 (China); Han Zhen [Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing 100085 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China); Bai Zhihui; Zhuang Guoqiang [Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Haidian District, Beijing 100085 (China); Shim Hojae [Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau (China)

    2010-05-15

    Environments with high-salt concentrations are often populated by dense microbial communities. Halophilic microorganisms can be isolated from different saline environments and different strains even belonging to the same genus have various applications. Wastewater and soil rich in both organic matter and salt are difficult to treat using conventional microorganisms typically found in wastewater treatment and soil bioremediation facilities. Studies on decontaminative capabilities and decontamination pathways of organic contaminants (i.e., aromatic compounds benzoate, cinnamate, 3-phenylpropionate, 4-hydroxybenzoic acid), heavy metals (i.e., tellurium, vanadium), and nutrients in the biological treatment of saline wastewater and soil by halophilic microorganisms are discussed in this review. - Review on the decontaminative capabilities of halophilic microorganisms in saline wastewater and soil.

  3. Halophilic microorganisms in deteriorated historic buildings: insights into their characteristics.

    Science.gov (United States)

    Adamiak, Justyna; Otlewska, Anna; Gutarowska, Beata; Pietrzak, Anna

    2016-01-01

    Historic buildings are constantly being exposed to numerous climatic changes such as damp and rainwater. Water migration into and out of the material's pores can lead to salt precipitation and the so-called efflorescence. The structure of the material may be seriously threatened by salt crystallization. A huge pressure is produced when salt hydrates occupy larger spaces, which leads at the end to cracking, detachment and material loss. Halophilic microorganisms have the ability to adapt to high salinity because of the mechanisms of inorganic salt (KCl or NaCl) accumulation in their cells at concentrations isotonic to the environment, or compatible solutes uptake or synthesis. In this study, we focused our attention on the determination of optimal growth conditions of halophilic microorganisms isolated from historical buildings in terms of salinity, pH and temperature ranges, as well as biochemical properties and antagonistic abilities. Halophilic microorganisms studied in this paper could be categorized as a halotolerant group, as they grow in the absence of NaCl, as well as tolerate higher salt concentrations (Staphylococcus succinus, Virgibacillus halodenitrificans). Halophilic microorganisms have been also observed (Halobacillus styriensis, H. hunanensis, H. naozhouensis, H. litoralis, Marinococcus halophilus and yeast Sterigmatomyces halophilus). With respect to their physiological characteristics, cultivation at a temperature of 25-30°C, pH 6-7, NaCl concentration for halotolerant and halophilic microorganisms, 0-10% and 15-30%, respectively, provides the most convenient conditions. Halophiles described in this study displayed lipolytic, glycolytic and proteolytic activities. Staphylococcus succinus and Marinococcus halophilus showed strong antagonistic potential towards bacteria from the Bacillus genus, while Halobacillus litoralis displayed an inhibiting ability against other halophiles.

  4. Factors Determining the Biodiversity of Halophilic Microorganisms on Historic Masonry Buildings

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    Otlewska, Anna; Adamiak, Justyna; Stryszewska, Teresa; Kańka, Stanisław; Gutarowska, Beata

    2017-01-01

    The aim of the present study was to obtain insights into the relationship between the chemical (salt content and pH) and physico-mechanical (humidity and compressive strength) properties of mineral-based materials from historic buildings with salt efflorescence and the growth and biodiversity of halophilic microorganisms. Samples were mainly characterized by pH 6.5–8.5 and a moisture content of between 0.12 and 3.3%. Significant variations were also found in the salt content (sulfates, chlorides, and nitrates) of the materials. An SEM/EDS analysis of material surfaces revealed the presence of halite, calcite, gypsum, sodium sulfate, and potassium-sodium sulfate. Culture-dependent and culture-independent (clone library construction) approaches were both applied to detect halophilic microorganisms. Results derived from culturable methods and the materials analysis revealed a correlation between the total halophile count and pH value as well as sulfate content. A correlation was not observed between the concentration of chlorides or nitrates and the number of halophilic microorganisms. The materials studied were inhabited by the culturable halophilic bacteria Halobacillus sp., Virgibacillus sp., and Marinococcus sp. as well as the yeast Sterigmatomyces sp., which was isolated for the first time from mineral materials. Culture-independent techniques revealed the following bacterial species: Salinibacterium, Salinisphaera, Rubrobacter, Rubricoccus, Halomonas, Halorhodospira, Solirubrobacter, Salinicoccus, and Salinibacter. Biodiversity was the highest in materials with high or moderate salinity. PMID:28592721

  5. Factors Determining the Biodiversity of Halophilic Microorganisms on Historic Masonry Buildings.

    Science.gov (United States)

    Otlewska, Anna; Adamiak, Justyna; Stryszewska, Teresa; Kańka, Stanisław; Gutarowska, Beata

    2017-06-24

    The aim of the present study was to obtain insights into the relationship between the chemical (salt content and pH) and physico-mechanical (humidity and compressive strength) properties of mineral-based materials from historic buildings with salt efflorescence and the growth and biodiversity of halophilic microorganisms. Samples were mainly characterized by pH 6.5-8.5 and a moisture content of between 0.12 and 3.3%. Significant variations were also found in the salt content (sulfates, chlorides, and nitrates) of the materials. An SEM/EDS analysis of material surfaces revealed the presence of halite, calcite, gypsum, sodium sulfate, and potassium-sodium sulfate. Culture-dependent and culture-independent (clone library construction) approaches were both applied to detect halophilic microorganisms. Results derived from culturable methods and the materials analysis revealed a correlation between the total halophile count and pH value as well as sulfate content. A correlation was not observed between the concentration of chlorides or nitrates and the number of halophilic microorganisms. The materials studied were inhabited by the culturable halophilic bacteria Halobacillus sp., Virgibacillus sp., and Marinococcus sp. as well as the yeast Sterigmatomyces sp., which was isolated for the first time from mineral materials. Culture-independent techniques revealed the following bacterial species: Salinibacterium, Salinisphaera, Rubrobacter, Rubricoccus, Halomonas, Halorhodospira, Solirubrobacter, Salinicoccus, and Salinibacter. Biodiversity was the highest in materials with high or moderate salinity.

  6. Biodeterioration Risk Threatens the 3100 Year Old Staircase of Hallstatt (Austria): Possible Involvement of Halophilic Microorganisms.

    Science.gov (United States)

    Piñar, Guadalupe; Dalnodar, Dennis; Voitl, Christian; Reschreiter, Hans; Sterflinger, Katja

    2016-01-01

    The prosperity of Hallstatt (Salzkammergut region, Austria) is based on the richness of salt in the surrounding mountains and salt mining, which is documented as far back as 1500 years B.C. Substantial archaeological evidence of Bronze and Iron Age salt mining has been discovered, with a wooden staircase (1108 B.C.) being one of the most impressive and well preserved finds. However, after its discovery, fungal mycelia have been observed on the surface of the staircase, most probably due to airborne contamination after its find. As a basis for the further preservation of this valuable object, the active micro-flora was examined to investigate the presence of potentially biodegradative microorganisms. Most of the strains isolated from the staircase showed to be halotolerant and halophilic microorganisms, due to the saline environment of the mine. Results derived from culture-dependent assays revealed a high fungal diversity, including both halotolerant and halophilic fungi, the most dominant strains being members of the genus Phialosimplex (synonym: Aspergillus). Additionally, some typical cellulose degraders, namely Stachybotrys sp. and Cladosporium sp. were detected. Numerous bacterial strains were isolated and identified as members of 12 different genera, most of them being moderately halophilic species. The most dominant isolates affiliated with species of the genera Halovibrio and Marinococcus. Halophilic archaea were also isolated and identified as species of the genera Halococcus and Halorubrum. Molecular analyses complemented the cultivation assays, enabling the identification of some uncultivable archaea of the genera Halolamina, Haloplanus and Halobacterium. Results derived from fungi and bacteria supported those obtained by cultivation methods, exhibiting the same dominant members in the communities. The results clearly showed the presence of some cellulose degraders that may become active if the requirements for growth and the environmental conditions

  7. Biodeterioration Risk Threatens the 3100 Year Old Staircase of Hallstatt (Austria: Possible Involvement of Halophilic Microorganisms.

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    Guadalupe Piñar

    Full Text Available The prosperity of Hallstatt (Salzkammergut region, Austria is based on the richness of salt in the surrounding mountains and salt mining, which is documented as far back as 1500 years B.C. Substantial archaeological evidence of Bronze and Iron Age salt mining has been discovered, with a wooden staircase (1108 B.C. being one of the most impressive and well preserved finds. However, after its discovery, fungal mycelia have been observed on the surface of the staircase, most probably due to airborne contamination after its find.As a basis for the further preservation of this valuable object, the active micro-flora was examined to investigate the presence of potentially biodegradative microorganisms.Most of the strains isolated from the staircase showed to be halotolerant and halophilic microorganisms, due to the saline environment of the mine. Results derived from culture-dependent assays revealed a high fungal diversity, including both halotolerant and halophilic fungi, the most dominant strains being members of the genus Phialosimplex (synonym: Aspergillus. Additionally, some typical cellulose degraders, namely Stachybotrys sp. and Cladosporium sp. were detected. Numerous bacterial strains were isolated and identified as members of 12 different genera, most of them being moderately halophilic species. The most dominant isolates affiliated with species of the genera Halovibrio and Marinococcus. Halophilic archaea were also isolated and identified as species of the genera Halococcus and Halorubrum. Molecular analyses complemented the cultivation assays, enabling the identification of some uncultivable archaea of the genera Halolamina, Haloplanus and Halobacterium. Results derived from fungi and bacteria supported those obtained by cultivation methods, exhibiting the same dominant members in the communities.The results clearly showed the presence of some cellulose degraders that may become active if the requirements for growth and the environmental

  8. Generation of PHB from Spent Sulfite Liquor Using Halophilic Microorganisms.

    Science.gov (United States)

    Weissgram, Michaela; Gstöttner, Janina; Lorantfy, Bettina; Tenhaken, Raimund; Herwig, Christoph; Weber, Hedda K

    2015-06-08

    Halophilic microorganisms thrive at elevated concentrations of sodium chloride up to saturation and are capable of growing on a wide variety of carbon sources like various organic acids, hexose and also pentose sugars. Hence, the biotechnological application of these microorganisms can cover many aspects, such as the treatment of hypersaline waste streams of different origin. Due to the fact that the high osmotic pressure of hypersaline environments reduces the risk of contamination, the capacity for cost-effective non-sterile cultivation can make extreme halophilic microorganisms potentially valuable organisms for biotechnological applications. In this contribution, the stepwise use of screening approaches, employing design of experiment (DoE) on model media and subsequently using industrial waste as substrate have been implemented to investigate the applicability of halophiles to generate PHB from the industrial waste stream spent sulfite liquor (SSL). The production of PHB on model media as well as dilutions of industrial substrate in a complex medium has been screened for by fluorescence microscopy using Nile Blue staining. Screening was used to investigate the ability of halophilic microorganisms to withstand the inhibiting substances of the waste stream without negatively affecting PHB production. It could be shown that neither single inhibiting substances nor a mixture thereof inhibited growth in the investigated range, hence, leaving the question on the inhibiting mechanisms open. However, it could be demonstrated that some haloarchaea and halophilic bacteria are able to produce PHB when cultivated on 3.3% w/w dry matter spent sulfite liquor, whereas H. halophila was even able to thrive on 6.6% w/w dry matter spent sulfite liquor and still produce PHB.

  9. Halophilic & halotolerant prokaryotes in humans.

    Science.gov (United States)

    Seck, El Hadji; Dufour, Jean-Charles; Raoult, Didier; Lagier, Jean-Christophe

    2018-05-04

    Halophilic prokaryotes are described as microorganisms living in hypersaline environments. Here, we list the halotolerant and halophilic bacteria which have been isolated in humans. Of the 52 halophilic prokaryotes, 32 (61.54%) were moderately halophilic, 17 (32.69%) were slightly halophilic and three (5.76%) were extremely halophilic prokaryotes. At the phylum level, 29 (54.72%) belong to Firmicutes, 15 (28.84%) to Proteobacteria, four (7.69%) to Actinobacteria, three (5.78%) to Euryarchaeota and one (1.92%) belongs to Bacteroidetes. Halophilic prokaryotes are rarely pathogenic: of these 52 halophilic prokaryotes only two (3.92%) species were classified in Risk Group 2 (Vibrio cholerae, Vibrio parahaemolyticus) and one (1.96%), species in Risk Group 3 (Bacillus anthracis).

  10. Halophilic microbial communities in deteriorated buildings.

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    Adamiak, Justyna; Otlewska, Anna; Gutarowska, Beata

    2015-10-01

    Halophilic microorganisms were traditionally isolated from an aquatic environment. There has been little research conducted into halophiles inhabiting the terrestrial environment in which historic monuments deteriorate. Salt efflorescence deposited on the walls is an observed phenomenon on the surface of historic buildings, and would favour the growth of halophiles. However, some conditions have to be fulfilled in order for efflorescence to occur: (1) the presence of salts, (2) porosity, (3) a source of water. Salt crystallization influences the material structure (cracking, detachment, material loss), but active growth of halophilic microorganisms may be a serious threat to historic materials as well, leading to aesthetical changes such as coloured biofilms, orange to pink or even violet stains. This is why it is important to investigate halophilic microorganisms, taking into consideration both the environmental conditions they need to grow in, material characteristics they inhabit, the mechanisms they possess to cope with osmotic stress, and the methods that should be applied for their identification.

  11. Screening and isolation of halophilic bacteria producing industrially important enzymes.

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    Kumar, Sumit; Karan, Ram; Kapoor, Sanjay; S P, Singh; S K, Khare

    2012-10-01

    Halophiles are excellent sources of enzymes that are not only salt stable but also can withstand and carry out reactions efficiently under extreme conditions. The aim of the study was to isolate and study the diversity among halophilic bacteria producing enzymes of industrial value. Screening of halophiles from various saline habitats of India led to isolation of 108 halophilic bacteria producing industrially important hydrolases (amylases, lipases and proteases). Characterization of 21 potential isolates by morphological, biochemical and 16S rRNA gene analysis found them related to Marinobacter, Virgibacillus, Halobacillus, Geomicrobium, Chromohalobacter, Oceanobacillus, Bacillus, Halomonas and Staphylococcus genera. They belonged to moderately halophilic group of bacteria exhibiting salt requirement in the range of 3-20%. There is significant diversity among halophiles from saline habitats of India. Preliminary characterization of crude hydrolases established them to be active and stable under more than one extreme condition of high salt, pH, temperature and presence of organic solvents. It is concluded that these halophilic isolates are not only diverse in phylogeny but also in their enzyme characteristics. Their enzymes may be potentially useful for catalysis under harsh operational conditions encountered in industrial processes. The solvent stability among halophilic enzymes seems a generic novel feature making them potentially useful in non-aqueous enzymology.

  12. THE HALOPHILICITY OF FILAMENTOUS FUNGI ISOLATED FROM SALINE SOILS OF SOUTH CAUCASUS

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    Kvesitadze E.

    2015-08-01

    Full Text Available The work is devoted to the isolation, purification, determination of taxonomical characteristics and application in soil improvement and other biotechnological processes halophilic microscopic fungi strains isolated from saline soils of Eastern Georgia (middle part of South Caucasus, where their existence is maximally supposed. In all soilclimatic zones the dominate forms of spread fungi are genera Aspergillus, Penicillium and Fusarium, followed by Trichoderma and Mucor. Other genera are met less intensively. The genera Aspergillus is widely spread in chestnut soils and in chernozem, in green forest soils the genera Penicillium is prevailing. The salinity of soil, lake or any other objects from which the isolation of microscopic fungi is performed greatly determines halophilisity of isolated strains. Finally, the collection of halophilic microscopic fungi has been created accounting 96 isolates of extreme halophiles, halophiles and week halophiles.

  13. Culturable diversity of halophilic bacteria in foreshore soils.

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    Irshad, Aarzoo; Ahmad, Irshad; Kim, Seung Bum

    2014-01-01

    Halophilic bacteria are commonly found in natural environments containing significant concentration of NaCl such as inland salt lakes and evaporated sea-shore pools, as well as environments such as curing brines, salted food products and saline soils. Dependence on salt is an important phenotypic characteristic of halophilic bacteria, which can be used in the polyphasic characterization of newly discovered microorganisms. In this study the diversity of halophilic bacteria in foreshore soils of Daecheon, Chungnam, and Saemangeum, Jeonbuk, was investigated. Two types of media, namely NA and R2A supplemented with 3%, 5%, 9%, 15%, 20% and 30% NaCl were used. More than 200 halophilic bacteria were isolated and BOX-PCR fingerprinting analysis was done for the typing of the isolates. The BLAST identification results showed that isolated strains were composed of 4 phyla, Firmicutes (60%), Proteobacteria (31%), Bacteriodetes (5%) and Actinobacteria (4%). Isolates were affiliated with 16 genera and 36 species. Bacillus was the dominant genus in the phylum Firmicutes, comprising 24% of the total isolates. Halomonas (12%) and Shewanella (12%) were also found as the main genera. These findings show that the foreshore soil of Daecheon Beach and Saemangeum Sea of Korea represents an untapped source of bacterial biodiversity.

  14. Culturable diversity of halophilic bacteria in foreshore soils

    Directory of Open Access Journals (Sweden)

    Aarzoo Irshad

    2014-06-01

    Full Text Available Halophilic bacteria are commonly found in natural environments containing significant concentration of NaCl such as inland salt lakes and evaporated sea-shore pools, as well as environments such as curing brines, salted food products and saline soils. Dependence on salt is an important phenotypic characteristic of halophilic bacteria, which can be used in the polyphasic characterization of newly discovered microorganisms. In this study the diversity of halophilic bacteria in foreshore soils of Daecheon, Chungnam, and Saemangeum, Jeonbuk, was investigated. Two types of media, namely NA and R2A supplemented with 3%, 5%, 9%, 15%, 20% and 30% NaCl were used. More than 200 halophilic bacteria were isolated and BOX-PCR fingerprinting analysis was done for the typing of the isolates. The BLAST identification results showed that isolated strains were composed of 4 phyla, Firmicutes (60%, Proteobacteria (31%, Bacteriodetes (5% and Actinobacteria (4%. Isolates were affiliated with 16 genera and 36 species. Bacillus was the dominant genus in the phylum Firmicutes, comprising 24% of the total isolates. Halomonas (12% and Shewanella (12% were also found as the main genera. These findings show that the foreshore soil of Daecheon Beach and Saemangeum Sea of Korea represents an untapped source of bacterial biodiversity.

  15. Isolation and characterization of extreme halophilic archaea

    Energy Technology Data Exchange (ETDEWEB)

    Franze, Madlen; Cherkouk, Andrea [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). HZDR Young Investigator Group

    2017-06-01

    Extreme halophilic archaea from the family Halobactereacea represent a dominant part of the microbial community present in saline soils as well as rock salts. By using a culture-dependent approach different Haloarchaea could be isolated and were phylogenetic analysed. Interestingly, isolates closely related to different Halobacterium spp. were found in both environments.

  16. Isolation and characterization of extreme halophilic archaea

    International Nuclear Information System (INIS)

    Franze, Madlen; Cherkouk, Andrea

    2017-01-01

    Extreme halophilic archaea from the family Halobactereacea represent a dominant part of the microbial community present in saline soils as well as rock salts. By using a culture-dependent approach different Haloarchaea could be isolated and were phylogenetic analysed. Interestingly, isolates closely related to different Halobacterium spp. were found in both environments.

  17. Application of lipopeptide biosurfactant isolated from a halophile: Bacillus tequilensis CH for inhibition of biofilm.

    Science.gov (United States)

    Pradhan, Arun Kumar; Pradhan, Nilotpala; Mall, Gangotri; Panda, Himadri Tanaya; Sukla, Lala Behari; Panda, Prasanna Kumar; Mishra, Barada Kanta

    2013-11-01

    Biosurfactants are amphiphilic molecules having hydrophobic and hydrophilic moieties produced by various microorganisms. These molecules trigger the reduction of surface tension or interfacial tension in liquids. A biosurfactant-producing halophile was isolated from Lake Chilika, a brackish water lake of Odisha, India (19°41'39″N, 85°18'24″E). The halophile was identified as Bacillus tequilensis CH by biochemical tests and 16S rRNA gene sequencing and assigned accession no. KC851857 by GenBank. The biosurfactant produced by B. tequilensis CH was partially characterized as a lipopeptide using thin-layer chromatography, Fourier transform infrared spectroscopy, and nuclear magnetic resonance techniques. The minimum effective concentration of a biosurfactant for inhibition of pathogenic biofilm (Escherichia coli and Streptococcus mutans) on hydrophilic and hydrophobic surfaces was found to be 50 μg ml(-1). This finding has potential for a variety of applications.

  18. [Experimental interaction of halophilic prokaryotes and opportunistic bacteria in brine].

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    Selivanova, E A; Nemtseva, N V

    2013-01-01

    Study the effect of extremely halophilic archaea and moderately halophilic bacteria on preservation of opportunistic bacteria in brine. 17 strains of moderately halophilic bacteria and 2 strains of extremely halophilic archaea were isolated from continental hypersaline lake Razval of Sol-Iletsk area of Orenburg Region. Identification of pure cultures of prokaryotes was carried out taking into account their phenotype properties and based on determination of 16S RNA gene sequence. The effect of halophilic prokaryote on elimination of Escherichia coli from brine was evaluated during co-cultivation. Antagonistic activity of cell extracts of the studied microorganisms was evaluated by photometric method. A more prolonged preservation of an E. coli strain in brine in the presence of live cells of extremely halophilic archaea Halorubrum tebenquichense and moderately halophilic bacteria Marinococcus halophilus was established. Extracts of cells of extremely halophilic archaea and moderately halophilic bacteria on the contrary displayed antagonistic activity. The protective effect of live cells of halophilic prokaryotes and antagonistic activity of their cell extracts change the period of conservation of opportunistic bacteria in brine that regulates inter-microbial interactions and changes the period of self-purification that reflects the sanitary condition of a hypersaline water body.

  19. Comparative analysis of uranium bioassociation with halophilic bacteria and archaea

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    Bader, Miriam; Müller, Katharina; Foerstendorf, Harald; Schmidt, Matthias; Simmons, Karen; Swanson, Juliet S.; Reed, Donald T.; Stumpf, Thorsten

    2018-01-01

    Rock salt represents a potential host rock formation for the final disposal of radioactive waste. The interactions between indigenous microorganisms and radionuclides, e.g. uranium, need to be investigated to better predict the influence of microorganisms on the safety assessment of the repository. Hence, the association process of uranium with two microorganisms isolated from rock salt was comparatively studied. Brachybacterium sp. G1, which was isolated from the German salt dome Gorleben, and Halobacterium noricense DSM15987T, were selected as examples of a moderately halophilic bacterium and an extremely halophilic archaeon, respectively. The microorganisms exhibited completely different association behaviors with uranium. While a pure biosorption process took place with Brachybacterium sp. G1 cells, a multistage association process occurred with the archaeon. In addition to batch experiments, in situ attenuated total reflection Fourier-transform infrared spectroscopy was applied to characterize the U(VI) interaction process. Biosorption was identified as the dominating process for Brachybacterium sp. G1 with this method. Carboxylic functionalities are the dominant interacting groups for the bacterium, whereas phosphoryl groups are also involved in U(VI) association by the archaeon H. noricense. PMID:29329319

  20. Taxonomic study of extreme halophilic archaea isolated from the "Salar de Atacama", Chile.

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    Lizama, C; Monteoliva-Sánchez, M; Prado, B; Ramos-Cormenzana, A; Weckesser, J; Campos, V

    2001-11-01

    A large number of halophilic bacteria were isolated in 1984-1992 from the Atacama Saltern (North of Chile). For this study 82 strains of extreme halophilic archaea were selected. The characterization was performed by using the phenotypic characters including morphological, physiological, biochemical, nutritional and antimicrobial susceptibility test. The results, together with those from reference strains, were subjected to numerical analysis, using the Simple Matching (S(SM)) coefficient and clustered by the unweighted pair group method of association (UPGMA). Fifteen phena were obtained at an 70% similarity level. The results obtained reveal a high diversity among the halophilic archaea isolated. Representative strains from the phena were chosen to determine their DNA base composition and the percentage of DNA-DNA similarity compared to reference strains. The 16S rRNA studies showed that some of these strains constitutes a new taxa of extreme halophilic archaea.

  1. Diversity of halophilic archaea in fermented foods and human intestines and their application.

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    Lee, Han-Seung

    2013-12-01

    Archaea are prokaryotic organisms distinct from bacteria in the structural and molecular biological sense, and these microorganisms are known to thrive mostly at extreme environments. In particular, most studies on halophilic archaea have been focused on environmental and ecological researches. However, new species of halophilic archaea are being isolated and identified from high salt-fermented foods consumed by humans, and it has been found that various types of halophilic archaea exist in food products by culture-independent molecular biological methods. In addition, even if the numbers are not quite high, DNAs of various halophilic archaea are being detected in human intestines and much interest is given to their possible roles. This review aims to summarize the types and characteristics of halophilic archaea reported to be present in foods and human intestines and to discuss their application as well.

  2. Characterization of halophilic C50 carotenoid-producing archaea isolated from solar saltworks in Bohai Bay, China

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    Sui, Liying; Liu, Liangsen; Deng, Yuangao

    2014-11-01

    Halophilic archaea comprise the majority of microorganisms found in hypersaline environments. C50 carotenoids accumulated in archaea cells are considered potential biotechnological products and possess a number of biological functions. Ten red colonies were isolated from brine water in a saltern crystallizer pond of the Hangu Saltworks, China. 16S rRNA gene sequence analysis showed that the colonies belonged to the extremely halophilic archaea genera Halobacterium and Halorubrum. Two representative strains, Halobacterium strain SP-2 and Halorubrum strain SP-4, were selected for further study on the phenotypic characteristics and effects of salinity and pH on accumulation and composition of pigments in their cells. The archaeal strains were isolated and grown in a culture medium prepared by dissolving yeast extract (10 g/L) and acid-hydrolyzed casein (7.5 g/L) into brine water obtained from a local salt pond. Their optimum salinity and pH for growth were 250 and 7, respectively, although pigment accumulation (OD490 / mL broth) was highest at pH 8. In addition, at 150-300 salinity, increasing salinity resulted in decreasing pigment accumulation. Analysis of the UV-Vis spectrum, TLC and HLPC chromatograms showed that C50 carotenoid bacterioruberin is the major pigment in both strains.

  3. [Community structure and diversity of culturable moderate halophilic bacteria isolated from Qrhan salt lake on Qinghai-Tibet Plateau].

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    Shen, Shuo

    2017-04-04

    I studied the community structure and diversity of culturable moderate halophilic bacteria isolated from Qrhan Salt Lake. I isolated and cultured the moderate halophilic bacteria on different selective media. After the 16S rRNA gene sequences was amplified and measured, I constructed the phylogenic tree, analyzed the community structure and calculated the diversity indexes according to the 16S rRNA gene information. A total of 421 moderate halophilic bacteria were isolated from water and mud samples in Qrhan Salt Lake. The 16S rRNA gene information showed that 4 potential novel species belonged to the family Bacillaceae. Eighty-three model strains belonged to 3 phylurms 6 families 16 genus. Among them, Bacillus sp., Oceanobacillus sp. and Halomonas sp. were dominant species. Diversity analysis showed that the diversity of strains isolated from water sample was higher than that from mud sample, but the dominance degree of strains isolated from mud sample was higher than that from water sample. The genetic diversity of moderate halophilic bacteria isolated from Qrhan Salt Lake was abundant. Also, there were dominant and novel species of culturable moderate halophilic bacteria in this lake.

  4. Isolation and characterization of halophilic lactic acid bacteria acting as a starter culture for sauce fermentation of the red alga Nori (Porphyra yezoensis).

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    Uchida, M; Miyoshi, T; Yoshida, G; Niwa, K; Mori, M; Wakabayashi, H

    2014-06-01

    A screening test was conducted for environmental samples to isolate halophilic lactic acid bacteria (HLAB) that can act as a starter in a Nori (Porphyra yezoensis)-sauce culture. After 9 months of incubation of enrichment cultures added with 25 kinds of environmental samples, growth of HLAB-like microorganisms was observed in six cultures salted at a 15% w/w level, including culture samples originally from mesopelagic water taken from 321 m-depth and from mountain snow taken at 2450 m-height. Ten strains were isolated and characterized as Tetragenococcus halophilus based on sequence analysis of the 16S rRNA gene. The isolates were inoculated into a newly prepared Nori-sauce culture and were confirmed to be able to act as a starter culture while three reference strains of T. halophilus obtained from a culture collection could not grow in the same culture. Halophilic lactic acid bacteria strains that can make growth in a highly salted Nori-sauce culture were isolated from environmental samples for the first time. All the isolates were identified as T. halophilus. The isolated strains are expected to be utilized as a starter culture for manufacturing fermented seaweed-sauce, which will be the first fermented food products obtained from algae. © 2014 The Society for Applied Microbiology.

  5. Actinopolyspora biskrensis sp. nov., a novel halophilic actinomycete isolated from Northern Sahara.

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    Saker, Rafika; Bouras, Noureddine; Meklat, Atika; Zitouni, Abdelghani; Schumann, Peter; Spröer, Cathrin; Klenk, Hans-Peter; Sabaou, Nasserdine

    2015-03-01

    A novel halophilic, filamentous actinomycete, designated H254(T), was isolated from a Saharan soil sample collected from Biskra (Northern Sahara), and subjected to a polyphasic taxonomic characterization. The strain is Gram-positive, aerobic, and halophilic, and the optimum NaCl concentration for growth is 15-20 % (w/v). The cell-wall hydrolysate contained meso-diaminopimelic acid, and the diagnostic whole-cell sugars were arabinose and galactose. The diagnostic phospholipid detected was phosphatidylcholine, and MK-9(H4) was the predominant menaquinone. The major fatty acid profiles were anteiso-C17:0 (32.8 %), C15:0 (28 %), and iso-C17:0 (12.3 %). Comparative analysis of the 16S rRNA gene sequences revealed that the strain H254(T) formed a well-separated sub-branch within the radiation of the genus Actinopolyspora, and the microorganism was most closely related to Actinopolyspora saharensis DSM 45459(T) (99.2 %), Actinopolyspora halophila DSM 43834(T) (99.1 %), and Actinopolyspora algeriensis DSM 45476(T) (99.0 %). Nevertheless, the strain had relatively lower mean values for DNA-DNA relatedness with the above strains (57.2, 68.4, and 45.6 %, respectively). Based on phenotypic features and phylogenetic position, we propose that strain H254(T) represents a novel species of the genus Actinopolyspora, for which the name Actinopolyspora biskrensis sp. nov. is proposed. The type strain of A. biskrensis is strain H254(T) (=DSM 46684(T) =CECT 8576(T)).

  6. Improvement of halophilic cellulase production from locally isolated fungal strain.

    Science.gov (United States)

    Gunny, Ahmad Anas Nagoor; Arbain, Dachyar; Jamal, Parveen; Gumba, Rizo Edwin

    2015-07-01

    Halophilic cellulases from the newly isolated fungus, Aspergillus terreus UniMAP AA-6 were found to be useful for in situ saccharification of ionic liquids treated lignocelluloses. Efforts have been taken to improve the enzyme production through statistical optimization approach namely Plackett-Burman design and the Face Centered Central Composite Design (FCCCD). Plackett-Burman experimental design was used to screen the medium components and process conditions. It was found that carboxymethylcellulose (CMC), FeSO4·7H2O, NaCl, MgSO4·7H2O, peptone, agitation speed and inoculum size significantly influence the production of halophilic cellulase. On the other hand, KH2PO4, KOH, yeast extract and temperature had a negative effect on enzyme production. Further optimization through FCCCD revealed that the optimization approach improved halophilic cellulase production from 0.029 U/ml to 0.0625 U/ml, which was approximately 2.2-times greater than before optimization.

  7. Perchlorate and halophilic prokaryotes: implications for possible halophilic life on Mars.

    Science.gov (United States)

    Oren, Aharon; Elevi Bardavid, Rahel; Mana, Lily

    2014-01-01

    In view of the finding of perchlorate among the salts detected by the Phoenix Lander on Mars, we investigated the relationships of halophilic heterotrophic microorganisms (archaea of the family Halobacteriaceae and the bacterium Halomonas elongata) toward perchlorate. All strains tested grew well in NaCl-based media containing 0.4 M perchlorate, but at the highest perchlorate concentrations, tested cells were swollen or distorted. Some species (Haloferax mediterranei, Haloferax denitrificans, Haloferax gibbonsii, Haloarcula marismortui, Haloarcula vallismortis) could use perchlorate as an electron acceptor for anaerobic growth. Although perchlorate is highly oxidizing, its presence at a concentration of 0.2 M for up to 2 weeks did not negatively affect the ability of a yeast extract-based medium to support growth of the archaeon Halobacterium salinarum. These findings show that presence of perchlorate among the salts on Mars does not preclude the possibility of halophilic life. If indeed the liquid brines that may exist on Mars are inhabited by salt-requiring or salt-tolerant microorganisms similar to the halophiles on Earth, presence of perchlorate may even be stimulatory when it can serve as an electron acceptor for respiratory activity in the anaerobic Martian environment.

  8. Microbial culturomics to isolate halophilic bacteria from table salt: genome sequence and description of the moderately halophilic bacterium Bacillus salis sp. nov.

    Directory of Open Access Journals (Sweden)

    E.H. Seck

    2018-05-01

    Full Text Available Bacillus salis strain ES3T (= CSUR P1478 = DSM 100598 is the type strain of B. salis sp. nov. It is an aerobic, Gram-positive, moderately halophilic, motile and spore-forming bacterium. It was isolated from commercial table salt as part of a broad culturomics study aiming to maximize the culture conditions for the in-depth exploration of halophilic bacteria in salty food. Here we describe the phenotypic characteristics of this isolate, its complete genome sequence and annotation, together with a comparison with closely related bacteria. Phylogenetic analysis based on 16S rRNA gene sequences indicated 97.5% similarity with Bacillus aquimaris, the closest species. The 8 329 771 bp long genome (one chromosome, no plasmids exhibits a G+C content of 39.19%. It is composed of 18 scaffolds with 29 contigs. Of the 8303 predicted genes, 8109 were protein-coding genes and 194 were RNAs. A total of 5778 genes (71.25% were assigned a putative function. Keywords: Bacillus salis, culturomics, genome, halophilic bacteria, human gut, taxonogenomics

  9. Diverse antimicrobial interactions of halophilic archaea and bacteria extend over geographical distances and cross the domain barrier.

    Science.gov (United States)

    Atanasova, Nina S; Pietilä, Maija K; Oksanen, Hanna M

    2013-10-01

    The significance of antimicrobial substances, halocins, produced by halophilic archaea and bacteria thriving in hypersaline environments is relatively unknown. It is suggested that their production might increase species diversity and give transient competitive advances to the producer strain. Halocin production is considered to be common among halophilic archaea, but there is a lack of information about halocins produced by bacteria in highly saline environments. We studied the antimicrobial activity of 68 halophilic archaea and 22 bacteria isolated from numerous geographically distant hypersaline environments. Altogether 144 antimicrobial interactions were found between the strains and aside haloarchaea, halophilic bacteria from various genera were identified as halocin producers. Close to 80% of the interactions were detected between microorganisms from different genera and in few cases, even across the domain boundary. Several of the strains produced halocins with a wide inhibitory spectrum as has been observed before. Most of the antimicrobial interactions were found between strains from distant sampling sites indicating that hypersaline environments around the world have similar microorganisms with the potential to produce wide activity range antimicrobials. © 2013 The Authors. MicrobiologyOpen published by John Wiley & Sons Ltd.

  10. Halophiles and their enzymes: Negativity put to good use

    Science.gov (United States)

    DasSarma, Shiladitya; DasSarma, Priya

    2015-01-01

    Halophilic microorganisms possess stable enzymes that function in very high salinity, an extreme condition that leads to denaturation, aggregation, and precipitation of most other proteins. Genomic and structural analyses have established that the enzymes of halophilic Archaea and many halophilic Bacteria are negatively charged due to an excess of acidic over basic residues, and altered hydrophobicity, which enhance solubility and promote function in low water activity conditions. Here, we provide an update on recent bioinformatic analysis of predicted halophilic proteomes as well as experimental molecular studies on individual halophilic enzymes. On-going efforts on discovery and utilization of halophiles and their enzymes for biotechnology, including biofuel applications are also considered. PMID:26066288

  11. Halophiles and their enzymes: negativity put to good use.

    Science.gov (United States)

    DasSarma, Shiladitya; DasSarma, Priya

    2015-06-01

    Halophilic microorganisms possess stable enzymes that function in very high salinity, an extreme condition that leads to denaturation, aggregation, and precipitation of most other proteins. Genomic and structural analyses have established that the enzymes of halophilic Archaea and many halophilic Bacteria are negatively charged due to an excess of acidic over basic residues, and altered hydrophobicity, which enhance solubility and promote function in low water activity conditions. Here, we provide an update on recent bioinformatic analysis of predicted halophilic proteomes as well as experimental molecular studies on individual halophilic enzymes. Recent efforts on discovery and utilization of halophiles and their enzymes for biotechnology, including biofuel applications are also considered. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. A novel halophilic lipase, LipBL, showing high efficiency in the production of eicosapentaenoic acid (EPA.

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    Dolores Pérez

    Full Text Available BACKGROUND: Among extremophiles, halophiles are defined as microorganisms adapted to live and thrive in diverse extreme saline environments. These extremophilic microorganisms constitute the source of a number of hydrolases with great biotechnological applications. The interest to use extremozymes from halophiles in industrial applications is their resistance to organic solvents and extreme temperatures. Marinobacter lipolyticus SM19 is a moderately halophilic bacterium, isolated previously from a saline habitat in South Spain, showing lipolytic activity. METHODS AND FINDINGS: A lipolytic enzyme from the halophilic bacterium Marinobacter lipolyticus SM19 was isolated. This enzyme, designated LipBL, was expressed in Escherichia coli. LipBL is a protein of 404 amino acids with a molecular mass of 45.3 kDa and high identity to class C β-lactamases. LipBL was purified and biochemically characterized. The temperature for its maximal activity was 80°C and the pH optimum determined at 25°C was 7.0, showing optimal activity without sodium chloride, while maintaining 20% activity in a wide range of NaCl concentrations. This enzyme exhibited high activity against short-medium length acyl chain substrates, although it also hydrolyzes olive oil and fish oil. The fish oil hydrolysis using LipBL results in an enrichment of free eicosapentaenoic acid (EPA, but not docosahexaenoic acid (DHA, relative to its levels present in fish oil. For improving the stability and to be used in industrial processes LipBL was immobilized in different supports. The immobilized derivatives CNBr-activated Sepharose were highly selective towards the release of EPA versus DHA. The enzyme is also active towards different chiral and prochiral esters. Exposure of LipBL to buffer-solvent mixtures showed that the enzyme had remarkable activity and stability in all organic solvents tested. CONCLUSIONS: In this study we isolated, purified, biochemically characterized and immobilized a

  13. Microbial culturomics to isolate halophilic bacteria from table salt: genome sequence and description of the moderately halophilic bacterium Bacillus salis sp. nov.

    Science.gov (United States)

    Seck, E H; Diop, A; Armstrong, N; Delerce, J; Fournier, P-E; Raoult, D; Khelaifia, S

    2018-05-01

    Bacillus salis strain ES3 T (= CSUR P1478 = DSM 100598) is the type strain of B. salis sp. nov. It is an aerobic, Gram-positive, moderately halophilic, motile and spore-forming bacterium. It was isolated from commercial table salt as part of a broad culturomics study aiming to maximize the culture conditions for the in-depth exploration of halophilic bacteria in salty food. Here we describe the phenotypic characteristics of this isolate, its complete genome sequence and annotation, together with a comparison with closely related bacteria. Phylogenetic analysis based on 16S rRNA gene sequences indicated 97.5% similarity with Bacillus aquimaris, the closest species. The 8 329 771 bp long genome (one chromosome, no plasmids) exhibits a G+C content of 39.19%. It is composed of 18 scaffolds with 29 contigs. Of the 8303 predicted genes, 8109 were protein-coding genes and 194 were RNAs. A total of 5778 genes (71.25%) were assigned a putative function.

  14. THE EXTREMELY HALOPHILIC MICROORGANISMS, A POSSIBLE MODEL FOR LIFE ON OTHER PLANETS

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    Sergiu Fendrihan

    2017-12-01

    Full Text Available Abstract The group of halophilic Archaea was discovered in the beginning of XX th century. They are able to live in more than 2-3 M of sodium chloride concentration that can be found in hypersaline natural lakes, in alkaline saline lakes, in man-made hypersaline mats, in rock salt, in very salted foods, on salted fish, on salted hides, in stromatolites, in saline soils. Their adaptations consist in resistance to high ionic contents with internal accumulation of K ions in order to face high Na ion content from the near environment. They belong to the Halobacteriaceae family. Their adaptation and their resistance to UV radiation and their resistance in oligotrophic conditions in rock salt, apparently over geological times, increase the possibility to find similar microorganisms in the Martian subsurface and in meteorites, and to support the panspermia theory. Some of the research of a working group in this field of activity and their possible uses are shortly reviewed here.

  15. Halophilic and haloalkaliphilic sulfur-oxidizing bacteria

    NARCIS (Netherlands)

    Sorokin, D.Y.; Banciu, H.; Robertson, L.A.; Kuenen, J.G.; Muntyan, M.S.; Muyzer, G.; Rosenberg, E.; DeLong, F.; Delong, E.; Lory, S.; Stackebrandt, E.; Thompson, F.

    2013-01-01

    Chemotrophic sulfur-oxidizing bacteria (SOB) represent an important functional group of microorganisms responsible for the dark oxidation of reduced sulfur compounds generated by sulfidogens. Until recently, only a single genus of halophilic SOB (Halothiobacillus) has been described, and nothing was

  16. Uranium association with halophilic and non-halophilic bacteria and archaea

    International Nuclear Information System (INIS)

    Francis, A.J.; Gillow, J.B.; Dodge, C.J.; Harris, R.; Beveridge, T.J.; Papenguth, H.W.

    2004-01-01

    We determined the association of uranium with bacteria isolated from the Waste Isolation Pilot Plant (WIPP), Carlsbad, New Mexico, and compared this with known strains of halophilic and non-halophilic bacteria and archaea. Examination of the cultures by transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS) showed uranium accumulation extracellularly and/or intracellularly to a varying degree. In Pseudomonas fluorescens and Bacillus subtilis uranium was associated with the cell surface and in the latter it was present as irregularly shaped grains. In Halobacterium halobium, the only archeon studied here, uranium was present as dense deposits and with Haloanaerobium praevalens as spikey deposits. Halomonas sp. isolated from the WIPP site accumulated uranium both extracellularly on the cell surface and intracellularly as electron-dense discrete granules. Extended X-ray absorption fine structure (EXAFS) analysis of uranium with the halophilic and non-halophilic bacteria and archaea showed that the uranium present in whole cells was bonded to an average of 2.4 ± 0.7 phosphoryl groups at a distance of 3.65 ± 0.03 Aa. Comparison of whole cells of Halomonas sp. with the cell wall fragments of lysed cells showed the presence of a uranium bidentate complex at 2.91 ± 0.03 Aa with the carboxylate group on the cell wall, and uranyl hydroxide with U-U interaction at 3.71 ± 0.03 Aa due to adsorption or precipitation reactions; no U-P interaction was observed. Addition of uranium to the cell lysate of Halomonas sp. resulted in the precipitation of uranium due to the inorganic phosphate produced by the cells. These results show that the phosphates released from bacteria bind a significant amount of uranium. However, the bacterially immobilized uranium was readily solubilized by bicarbonate with concurrent release of phosphate into solution. (orig.)

  17. Identification of halophile bacteria from salt deserts of Iran and study some of their physiological traits

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    Maryam Safdarian

    2017-06-01

    Full Text Available Introduction: Halophiles and halotolerant microorganisms are some of the extremophiles that are able to grow in medium containing sodium chloride and have adapted to life in salinity environments. Halophiles bacteria in saline soils by maintaining the food chain, decomposition of organic matter and improvement of soil structure and fertility improve soil conditions. Materials and methods: In order to isolate the halotoletant bacteria, from the halophyte rhizosphere, four desert areas in Golestan province were sampled. To check the Extremophile of isolates, their resistance was tested for resistant to salinity, drought, temperature and PH. Also, plant growth promoting traits were measured. Results: Fromforty-five strains which were isolated, three strains (G3, G6 and G14 have demonstrated the ability of resistance to 35% salt. Isolates G6 and G3 phosphate solubiliziation power of 301 and 201 ppm, respectively. Isolated G6 micrograms produced auxin 20/7 Mg/ ml. G14 and G6 grow at 50 °C, pH = 10 and osmotic potential -0 /7MPa. While G3 strain grows at 50 °C, pH = 7/ 5 and osmotic potential -0/49. The three strains of the bacterial genera Bacillus and Pseudomonas, respectively. Discussion and conclusion: In this study, isolates due to the growth in concentrations of salt and saturated salt tolerance of extreme environmental conditions and are likely halotolerant or halophile bacteria and its potential for use in various fields of biotechnology including biotech, industrial enzyme production and biological fertilizers for saline soil improvement.

  18. Draft genome sequence of the extremely halophilic archaeon Haladaptatus cibarius type strain D43(T) isolated from fermented seafood.

    Science.gov (United States)

    Lee, Hae-Won; Kim, Dae-Won; Lee, Mi-Hwa; Kim, Byung-Yong; Cho, Yong-Joon; Yim, Kyung June; Song, Hye Seon; Rhee, Jin-Kyu; Seo, Myung-Ji; Choi, Hak-Jong; Choi, Jong-Soon; Lee, Dong-Gi; Yoon, Changmann; Nam, Young-Do; Roh, Seong Woon

    2015-01-01

    An extremely halophilic archaeon, Haladaptatus cibarius D43(T), was isolated from traditional Korean salt-rich fermented seafood. Strain D43(T) shows the highest 16S rRNA gene sequence similarity (98.7 %) with Haladaptatus litoreus RO1-28(T), is Gram-negative staining, motile, and extremely halophilic. Despite potential industrial applications of extremely halophilic archaea, their genome characteristics remain obscure. Here, we describe the whole genome sequence and annotated features of strain D43(T). The 3,926,724 bp genome includes 4,092 protein-coding and 57 RNA genes (including 6 rRNA and 49 tRNA genes) with an average G + C content of 57.76 %.

  19. The Function of Gas Vesicles in Halophilic Archaeaand Bacteria: Theories and Experimental Evidence

    Science.gov (United States)

    Oren, Aharon

    2012-01-01

    A few extremely halophilic Archaea (Halobacterium salinarum, Haloquadratum walsbyi, Haloferax mediterranei, Halorubrum vacuolatum, Halogeometricum borinquense, Haloplanus spp.) possess gas vesicles that bestow buoyancy on the cells. Gas vesicles are also produced by the anaerobic endospore-forming halophilic Bacteria Sporohalobacter lortetii and Orenia sivashensis. We have extensive information on the properties of gas vesicles in Hbt. salinarum and Hfx. mediterranei and the regulation of their formation. Different functions were suggested for gas vesicle synthesis: buoying cells towards oxygen-rich surface layers in hypersaline water bodies to prevent oxygen limitation, reaching higher light intensities for the light-driven proton pump bacteriorhodopsin, positioning the cells optimally for light absorption, light shielding, reducing the cytoplasmic volume leading to a higher surface-area-to-volume ratio (for the Archaea) and dispersal of endospores (for the anaerobic spore-forming Bacteria). Except for Hqr. walsbyi which abounds in saltern crystallizer brines, gas-vacuolate halophiles are not among the dominant life forms in hypersaline environments. There only has been little research on gas vesicles in natural communities of halophilic microorganisms, and the few existing studies failed to provide clear evidence for their possible function. This paper summarizes the current status of the different theories why gas vesicles may provide a selective advantage to some halophilic microorganisms. PMID:25371329

  20. Untargeted Metabolomics Approach in Halophiles: Understanding the Biodeterioration Process of Building Materials

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    Justyna Adamiak

    2017-12-01

    Full Text Available The aim of the study was to explore the halophile metabolome in building materials using untargeted metabolomics which allows for broad metabolome coverage. For this reason, we used high-performance liquid chromatography interfaced to high-resolution mass spectrometry (HPLC/HRMS. As an alternative to standard microscopy techniques, we introduced pioneering Coherent Anti-stokes Raman Scattering Microscopy (CARS to non-invasively visualize microbial cells. Brick samples saturated with salt solution (KCl, NaCl (two salinity levels, MgSO4, Mg(NO32, were inoculated with the mixture of preselected halophilic microorganisms, i.e., bacteria: Halobacillus styriensis, Halobacillus naozhouensis, Halobacillus hunanensis, Staphylococcus succinus, Marinococcus halophilus, Virgibacillus halodenitryficans, and yeast: Sterigmatomyces halophilus and stored at 28°C and 80% relative humidity for a year. Metabolites were extracted directly from the brick samples and measured via HPLC/HRMS in both positive and negative ion modes. Overall, untargeted metabolomics allowed for discovering the interactions of halophilic microorganisms with buildings materials which together with CARS microscopy enabled us to elucidate the biodeterioration process caused by halophiles. We observed that halophile metabolome was differently affected by different salt solutions. Furthermore, we found indications for haloadaptive strategies and degradation of brick samples due to microbial pigment production as a salt stress response. Finally, we detected changes in lipid content related to changes in the structure of phospholipid bilayers and membrane fluidity.

  1. Global transcriptome analysis of Halolamina sp. to decipher the salt tolerance in extremely halophilic archaea.

    Science.gov (United States)

    Kurt-Kızıldoğan, Aslıhan; Abanoz, Büşra; Okay, Sezer

    2017-02-15

    Extremely halophilic archaea survive in the hypersaline environments such as salt lakes or salt mines. Therefore, these microorganisms are good sources to investigate the molecular mechanisms underlying the tolerance to high salt concentrations. In this study, a global transcriptome analysis was conducted in an extremely halophilic archaeon, Halolamina sp. YKT1, isolated from a salt mine in Turkey. A comparative RNA-seq analysis was performed using YKT1 isolate grown either at 2.7M NaCl or 5.5M NaCl concentrations. A total of 2149 genes were predicted to be up-regulated and 1638 genes were down-regulated in the presence of 5.5M NaCl. The salt tolerance of Halolamina sp. YKT1 involves the up-regulation of genes related with membrane transporters, CRISPR-Cas systems, osmoprotectant solutes, oxidative stress proteins, and iron metabolism. On the other hand, the genes encoding the proteins involved in DNA replication, transcription, translation, mismatch and nucleotide excision repair were down-regulated. The RNA-seq data were verified for seven up-regulated genes as well as six down-regulated genes via qRT-PCR analysis. This comprehensive transcriptome analysis showed that the halophilic archaeon canalizes its energy towards keeping the intracellular osmotic balance minimizing the production of nucleic acids and peptides. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. DNA Repair and Photoprotection: Mechanisms of Overcoming Environmental Ultraviolet Radiation Exposure in Halophilic Archaea.

    Science.gov (United States)

    Jones, Daniel L; Baxter, Bonnie K

    2017-01-01

    Halophilic archaea push the limits of life at several extremes. In particular, they are noted for their biochemical strategies in dealing with osmotic stress, low water activity and cycles of desiccation in their hypersaline environments. Another feature common to their habitats is intense ultraviolet (UV) radiation, which is a challenge that microorganisms must overcome. The consequences of high UV exposure include DNA lesions arising directly from bond rearrangement of adjacent bipyrimidines, or indirectly from oxidative damage, which may ultimately result in mutation and cell death. As such, these microorganisms have evolved a number of strategies to navigate the threat of DNA damage, which we differentiate into two categories: DNA repair and photoprotection. Photoprotection encompasses damage avoidance strategies that serve as a "first line of defense," and in halophilic archaea include pigmentation by carotenoids, mechanisms of oxidative damage avoidance, polyploidy, and genomic signatures that make DNA less susceptible to photodamage. Photolesions that do arise are addressed by a number of DNA repair mechanisms that halophilic archaea efficiently utilize, which include photoreactivation, nucleotide excision repair, base excision repair, and homologous recombination. This review seeks to place DNA damage, repair, and photoprotection in the context of halophilic archaea and the solar radiation of their hypersaline environments. We also provide new insight into the breadth of strategies and how they may work together to produce remarkable UV-resistance for these microorganisms.

  3. [Diversity and enzyme-producing activity of culturable halophilic bacteria in Daishan Saltern of East China].

    Science.gov (United States)

    Yang, Dan-Dan; Li, Qian; Huang, Jing-Jing; Chen, Min

    2012-11-01

    Soil and saline water samples were collected from the Daishan Saltern of East China, and the halophilic bacteria were isolated and cultured by using selective media, aimed to investigate the diversity and enzyme-producing activity of culturable halophilic bacteria in saltern environment. A total of 181 strains were isolated by culture-dependent method. Specific primers were used to amplify the 16S rRNA gene of bacteria and archaea. The operation taxonomy units (OTUs) were determined by ARDRA method, and the representative strain of each OTU was sequenced. The phylogenetic position of all the isolated strains was determined by 16S rRNA sequencing. The results showed that the isolated 181 strains displayed 21 operational taxonomic units (OTUs), of which, 12 OTUs belonged to halophilic bacteria, and the others belonged to halophilic archaea. Phylogenetic analysis indicated that there were 7 genera presented among the halophilic bacteria group, and 4 genera presented among the halophilic archaea group. The dominant halophilic strains were of Halomonas and Haloarcula, with 46.8% in halophilic bacteria and 49.1% in halophilic archaea group, respectively. Enzyme-producing analysis indicated that most strains displayed enzyme-producing activity, including the activities of producing amylase, proteinase and lipase, and the dominant strains capable of enzyme-producing were of Haloarcula. Our results showed that in the environment of Daishan Saltern, there existed a higher diversity of halophilic bacteria, being a source sink for screening enzyme-producing bacterial strains.

  4. Transposon-mediated random gene disruption with moderate halophilic bacteria and its application for halophilic bacterial siderophore analysis.

    Science.gov (United States)

    Matsui, Toru; Nishino, Tomohiko

    2016-12-01

    Analytical conditions using chromo azurol S was validated for quantification of siderophore in aqueous samples, followed by the characterization of siderophore derived from newly isolated moderately halophilic bacteria. Conditions with good linearity between the absorbance and the siderophore concentration were obtained at a siderophore concentration less than 20 µM, in the wavelength range between 630 and 660 nm with developing time for at least 2 h. Of the halophilic bacteria isolated from Tunisian soil, Halomonas sp., namely strain 21a was selected as siderophore producing halophiles. The strain produced siderophore significantly in the absence of iron in minimal medium. Siderophore-deficient mutant, namely IIa10, of the strain 21a was obtained from gene disruptant library constructed using transposon complex by electroporation. Genomic sequence analysis of the mutant IIa10 revealed that the transposon-inserted gene was TonB-dependent receptor. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Isolation and identification of poly-extremophilic alkalophilic, halophilic and halotolerant bacteria from alkaline thalassohaline Gomishan wetland

    Directory of Open Access Journals (Sweden)

    Azadeh Shahinpei

    2013-06-01

    Full Text Available Gomishan wetland is a natural ecosystem located in 35 km north west of Gorgan, in the west vicinity of Khajeh Nafas city and Gomishan. Twice sampling from 3 different geographic positions in dry and rainy seasons, led to the isolation of 224 isolates. For 57 isolates, halophilic and halotolerant behaviors and also optimum and growth range in different pH and temperatures were determined. Most of the moderately halophilic and halotolerant strains were capable of growing optimally in media with pH 8.5-9 and optimum growth temperatures ranging from <4 to 40 °C. The isolates were examined for hydrolytic enzymes production. Most of the isolates showed lipase activites and a total of 15, 7 and 3 strains produced amylases, proteases and DNases, respectively. The enzymes could be useful in some industrial processes. 16S rDNA phylogenetic analysis were done for 55 strains. According to this analysis, strains were placed in 22 different genera: Achromobacter, Aeromicrobium, Altererythrobacter, Bacillus, Caenispirillum, Cyclobacterium, Erythrobacter, Halobacillus, Halomonas, Idiomarina, Jonesia, Marinobacter, Martelella, Nesiotobacter, Paenibacillus, Planococcus, Pseudomonas, Rheinheimera, Saccharospirillum, Stappia, Thalassospira and Vibrio. 23% of these strains were haloalkalophilic bacteria and belonged to the Bacillus, Halobacillus, Halomonas, Idiomarina and Marinobacter. This was the first study on the culturable bacteria at Gomishan wetland, an area of considerable alkaline thalassohaline ecosystem.

  6. Characterization and antimicrobial potential of extremely halophilic archaea isolated from hypersaline environments of the Algerian Sahara.

    Science.gov (United States)

    Quadri, Inès; Hassani, Imene Ikrame; l'Haridon, Stéphane; Chalopin, Morgane; Hacène, Hocine; Jebbar, Mohamed

    2016-01-01

    Halophilic archaea were isolated from different chotts and sebkha, dry salt lakes and salt flat respectively, of the Algerian Sahara and characterized using phenotypic and phylogenetic approaches. From 102 extremely halophilic strains isolated, forty three were selected and studied. These strains were also screened for their antagonistic potential and the production of hydrolytic enzymes. Sequencing of the 16S rRNA genes and phylogenetic analysis allowed the identification of 10 archaeal genera within the class Halobacteria: Natrinema (13 strains), Natrialba (12 strains), Haloarcula (4 strains), Halopiger (4 strains), Haloterrigena (3 strains), Halorubrum (2 strains), Halostagnicola (2 strains), Natronococcus, Halogeometricum and Haloferax (1 strain each). The most common producers of antimicrobial compounds belong to the genus Natrinema while the most hydrolytic isolates, with combined production of several enzymes, belong to the genus Natrialba. The strain affiliated to Halopiger djelfamassilliensis was found to produce some substances of interest (halocins, anti-Candida, enzymes). After partial purification and characterization of one of the strains Natrinema gari QI1, we found similarities between the antimicrobial compound and the halocin C8. Therefore, the gene encoding halocin C8 was amplified and sequenced. Copyright © 2016 Elsevier GmbH. All rights reserved.

  7. Isolation and characterization of Arctic microorganisms decomposing bioplastics.

    Science.gov (United States)

    Urbanek, Aneta K; Rymowicz, Waldemar; Strzelecki, Mateusz C; Kociuba, Waldemar; Franczak, Łukasz; Mirończuk, Aleksandra M

    2017-12-01

    The increasing amount of plastic waste causes significant environmental pollution. In this study, screening of Arctic microorganisms which are able to degrade bioplastics was performed. In total, 313 microorganisms were isolated from 52 soil samples from the Arctic region (Spitsbergen). Among the isolated microorganisms, 121 (38.66%) showed biodegradation activity. The ability of clear zone formation on emulsified poly(butylene succinate-co-adipate) (PBSA) was observed for 116 microorganisms (95.87%), on poly(butylene succinate) (PBS) for 73 microorganisms (60.33%), and on poly(ɛ-caprolactone) (PCL) for 102 microorganisms (84.3%). Moreover, the growth of microorganisms on poly(lactic acid) (PLA) agar plates was observed for 56 microorganisms (46.28%). Based on the 16S rRNA sequence, 10 bacterial strains which showed the highest ability for biodegradation were identified as species belonging to Pseudomonas sp. and Rhodococcus sp. The isolated fungal strains were tested for polycaprolactone films and commercial corn and potato starch bags degradation under laboratory conditions. Strains 16G (based on the analysis of a partial 18S rRNA sequence, identified as Clonostachys rosea) and 16H (identified as Trichoderma sp.) showed the highest capability for biodegradation. A particularly high capability for biodegradation was observed for the strain Clonostachys rosea, which showed 100% degradation of starch films and 52.91% degradation of PCL films in a 30-day shake flask experiment. The main advantage of the microorganisms isolated from Arctic environment is the ability to grow at low temperature and efficient biodegradation under this condition. The data suggest that C. rosea can be used in natural and laboratory conditions for degradations of bioplastics.

  8. DNA Repair and Photoprotection: Mechanisms of Overcoming Environmental Ultraviolet Radiation Exposure in Halophilic Archaea

    Directory of Open Access Journals (Sweden)

    Daniel L. Jones

    2017-09-01

    Full Text Available Halophilic archaea push the limits of life at several extremes. In particular, they are noted for their biochemical strategies in dealing with osmotic stress, low water activity and cycles of desiccation in their hypersaline environments. Another feature common to their habitats is intense ultraviolet (UV radiation, which is a challenge that microorganisms must overcome. The consequences of high UV exposure include DNA lesions arising directly from bond rearrangement of adjacent bipyrimidines, or indirectly from oxidative damage, which may ultimately result in mutation and cell death. As such, these microorganisms have evolved a number of strategies to navigate the threat of DNA damage, which we differentiate into two categories: DNA repair and photoprotection. Photoprotection encompasses damage avoidance strategies that serve as a “first line of defense,” and in halophilic archaea include pigmentation by carotenoids, mechanisms of oxidative damage avoidance, polyploidy, and genomic signatures that make DNA less susceptible to photodamage. Photolesions that do arise are addressed by a number of DNA repair mechanisms that halophilic archaea efficiently utilize, which include photoreactivation, nucleotide excision repair, base excision repair, and homologous recombination. This review seeks to place DNA damage, repair, and photoprotection in the context of halophilic archaea and the solar radiation of their hypersaline environments. We also provide new insight into the breadth of strategies and how they may work together to produce remarkable UV-resistance for these microorganisms.

  9. Isolation and characterization of halophilic bacteria and archaea from salt ponds in Hangu Saltworks, Tianjin, China

    Science.gov (United States)

    Deng, Yuangao; Xu, Gaochao; Sui, Liying

    2015-07-01

    A total of 26 isolates were obtained from solar salt ponds of different salinities (100, 150, 200, and 250) in Hangu Saltworks Co. Ltd., Tianjin, China. Phylogenetic analysis of 16S rRNA gene sequences indicated that five bacteria genera Halomonas, Salinicoccus, Oceanobacillus, Gracibacillus, and Salimicrobium and one archaea genera Halorubrum were present. The genus Halomonas was predominant with eight strains distributed in a salinity range of 100-200, followed by Halorubrum with six strains in salinity 250. Based on the genus and original sampling salinity, eight bacterial and two archaeal isolates were selected for further morphological, physiological, and biochemical characterization. All of the bacterial strains were moderately halophilic with the optimal salinity for growth being either 50 or 100, while two archaeal strains were extremely halophilic with an optimal growth salinity of 200. Additionally, we put forth strain SM.200-5 as a new candidate Salimicrobium species based on the phylogenic analysis of the 16S rRNA gene sequence and its biochemical characteristics when compared with known related species.

  10. Halophilic biohydrogen and 1,3-propanediol production from raw glycerol: A genomic perspective

    Energy Technology Data Exchange (ETDEWEB)

    Kivisto, A.

    2013-11-01

    Glycerol is produced in large amounts as a by-product in biodiesel industry (10 kg per 100 kg biodiesel). By-products and waste materials are typically economical substrates for bioprocesses. Furthermore, microorganisms are able to combine the degradation of organic material with production of a wide range of metabolites and other cellular products. The current biotechnological interest of industrial glycerol lies on bioprocesses yielding environmentally friendly energy carrier molecules (hydrogen, methane, ethanol, butanol) and reduced chemicals (1,3-propanediol, dihydroxyacetone). Industrial glycerol also called as raw or crude glycerol, however, is a challenging substrate for microorganisms due to its impurities including alcohol, soaps, salts and metals. Halophiles (the salt-loving microorganisms) require salt for growth and heavy metal resistances have been characterized for numerous halophiles. Therefore, halophiles are potentially useful for the utilization of raw glycerol from biodiesel waste streams without pre-processing. Another challenge for large-scale microbial bioprocesses is a potential contamination with unfavorable microorganisms. For example, H{sub 2}-producing systems tend to get contaminated with H{sub 2}-consuming microorganisms. Extremophiles are organisms that have been adapted for life under extreme conditions, such as high salinity, high or low temperature, asidic or basic pH, dryness or high pressure. For extremophilic pure cultures contamination and thus the need to ensure a sterile environment might not be a problem due to the extreme process conditions that efficiently prevent the growth of most other bacteria. In addition, hypersaline environments (above 12 % NaCl) do not support the growth of H{sub 2} utilizing methanogens due to bioenergetic reasons. Halophilic fermentative H{sub 2} producers, on the other hand, have been shown to be active up to near salt saturation. The aims of the present study can be divided into two categories

  11. Sorption behavior of europium(III) and curium(III) on the cell surfaces of microorganisms

    International Nuclear Information System (INIS)

    Ozaki, T.; Kimura, T.; Ohnuki, T.; Yoshida, Z.; Gillow, J.B.; Francis, A.J.

    2004-01-01

    We investigated the association of europium(III) and curium(III) with the microorganisms Chlorella vulgaris, Bacillus subtilis, Pseudomonas fluorescens, Halomonas sp., Halobacterium salinarum, and Halobacterium halobium. We determined the kinetics and distribution coefficients (K d ) for Eu(III) and Cm(III) sorption at pH 3-5 by batch experiments, and evaluated the number of water molecules in the inner-sphere (N H 2 O ) and the degree of strength of ligand field (R E/M ) for Eu(III) by time-resolved laser-induced fluorescence spectroscopy (TRLFS). Exudates from C. vulgaris, Halomonas sp., and H. halobium had an affinity for Eu(III) and Cm(III). The log K d of Eu(III) and Cm(III) showed that their sorption was not fully due to the exchange with three protons on the functional groups on cell surfaces. The halophilic microorganisms (Halomonas sp., Halobacterium salinarum, H. halobium) showed almost no pH dependence in log K d , indicating that an exchange with Na + on the functional groups was involved in their sorption. The ΔN H 2 O (= 9 - N H 2 O ) for Eu(III) on C. vulgaris was 1-3, while that for the other microorganisms was over 3, demonstrating that the coordination of Eu(III) with C. vulgaris was predominantly an outer-spherical process. The R E/M for Eu(III) on halophilic microorganisms was 2.5-5, while that for non-halophilic ones was 1-2.5. This finding suggests that the coordination environment of Eu(III) on the halophilic microorganisms is more complicated than that on the other three non-halophilic ones. (orig.)

  12. Sorption behavior of europium(III) and curium(III) on the cell surfaces of microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Ozaki, T.; Kimura, T.; Ohnuki, T.; Yoshida, Z. [Advanced Science Research Center, Japan Atomic Energy Research Inst., Ibaraki (Japan); Gillow, J.B.; Francis, A.J. [Environmental Sciences Dept., Brookhaven National Lab., Upton, NY (United States)

    2004-07-01

    We investigated the association of europium(III) and curium(III) with the microorganisms Chlorella vulgaris, Bacillus subtilis, Pseudomonas fluorescens, Halomonas sp., Halobacterium salinarum, and Halobacterium halobium. We determined the kinetics and distribution coefficients (K{sub d}) for Eu(III) and Cm(III) sorption at pH 3-5 by batch experiments, and evaluated the number of water molecules in the inner-sphere (N{sub H{sub 2}O}) and the degree of strength of ligand field (R{sub E/M}) for Eu(III) by time-resolved laser-induced fluorescence spectroscopy (TRLFS). Exudates from C. vulgaris, Halomonas sp., and H. halobium had an affinity for Eu(III) and Cm(III). The log K{sub d} of Eu(III) and Cm(III) showed that their sorption was not fully due to the exchange with three protons on the functional groups on cell surfaces. The halophilic microorganisms (Halomonas sp., Halobacterium salinarum, H. halobium) showed almost no pH dependence in log K{sub d}, indicating that an exchange with Na{sup +} on the functional groups was involved in their sorption. The {delta}N{sub H{sub 2}O} (= 9 - N{sub H{sub 2}O}) for Eu(III) on C. vulgaris was 1-3, while that for the other microorganisms was over 3, demonstrating that the coordination of Eu(III) with C. vulgaris was predominantly an outer-spherical process. The R{sub E/M} for Eu(III) on halophilic microorganisms was 2.5-5, while that for non-halophilic ones was 1-2.5. This finding suggests that the coordination environment of Eu(III) on the halophilic microorganisms is more complicated than that on the other three non-halophilic ones. (orig.)

  13. Isolation and characterization of halophilic Bacillus sp. BS3 able to produce pharmacologically important biosurfactants.

    Science.gov (United States)

    Donio, M B S; Ronica, S F A; Viji, V Thanga; Velmurugan, S; Jenifer, J Adlin; Michaelbabu, M; Citarasu, T

    2013-11-01

    To characterize the pharmacological importance of biosurfactants isolated from halophilic Bacillus sp BS3. Halophilic Bacillus sp. BS3 was isolated from solar salt works, identified by 16S rRNA sequencing and was used for screening their biosurfactant production. Characters of the biosurfactant and their anticancer activity were analyzed and performed in mammary epithelial carcinoma cell at different concentrations. The biosurfactant were characterized by TLC, FTIR and GC-MS analysis and identified as lipopeptide type. GC-MS analysis revealed that, the biosurfactant had various compounds including 13-Docosenamide, (Z); Mannosamine, 9- and N,N,N',N'-tetramethyl. Surprisingly the antiviral activity was found against shrimp white spot syndrome virus (WSSV) by suppressing the viral replication and significantly raised shrimp survival (Pbiosurfactants, among the various concentrations of biosurfactants such as 0.000 25, 0.002 5, 0.025, 0.25 and 2.5 μg, the 0.25 μg concentration suppressed the cells significantly (P<0.05) to 24.8%. Based on the findings, the present study concluded that, there is a possibility to develop eco-friendly antimicrobial and anticancer drugs from the extremophilic origin. Copyright © 2013 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

  14. Diversity of halophilic archaea from six hypersaline environments in Turkey.

    Science.gov (United States)

    Ozcan, Birgul; Ozcengiz, Gulay; Coleri, Arzu; Cokmus, Cumhur

    2007-06-01

    The diversity of archaeal strains from six hypersaline environments in Turkey was analyzed by comparing their phenotypic characteristics and 16S rDNA sequences. Thirty-three isolates were characterized in terms of their phenotypic properties including morphological and biochemical characteristics, susceptibility to different antibiotics, and total lipid and plasmid contents, and finally compared by 16S rDNA gene sequences. The results showed that all isolates belong to the family Halobacteriaceae. Phylogenetic analyses using approximately 1,388 bp comparisions of 16S rDNA sequences demonstrated that all isolates clustered closely to species belonging to 9 genera, namely Halorubrum (8 isolates), Natrinema (5 isolates), Haloarcula (4 isolates), Natronococcus (4 isolates), Natrialba (4 isolates), Haloferax (3 isolates), Haloterrigena (3 isolates), Halalkalicoccus (1 isolate), and Halomicrobium (1 isolate). The results revealed a high diversity among the isolated halophilic strains and indicated that some of these strains constitute new taxa of extremely halophilic archaea.

  15. Extracellular polymer substance synthesized by a halophilic bacterium Chromohalobacter canadensis 28.

    Science.gov (United States)

    Radchenkova, Nadja; Boyadzhieva, Ivanka; Atanasova, Nikolina; Poli, Annarita; Finore, Ilaria; Di Donato, Paola; Nicolaus, Barbara; Panchev, Ivan; Kuncheva, Margarita; Kambourova, Margarita

    2018-04-03

    Halophilic microorganisms are producers of a lot of new compounds whose properties suggest promising perspectives for their biotechnological exploration. Moderate halophilic bacterium Chromohalobacter canadensis 28 was isolated from Pomorie salterns as an extracellular polymer substance (EP) producer. The best carbon source for extracellular polymer production was found to be lactose, a sugar received as a by-product from the dairy industry. After optimization of the culture medium and physicochemical conditions for cultivation, polymer biosynthesis increased more than 2-fold. The highest level of extracellular polymer synthesis by C. canadensis 28 was observed in an unusually high NaCl concentration (15% w/v). Chemical analysis of the purified polymer revealed the presence of an exopolysaccharide (EPS) fraction (14.3% w/w) and protein fraction (72% w/w). HPLC analysis of the protein fraction showed the main presence of polyglutamic acid (PGA) (75.7% w/w). EPS fraction analysis revealed the following sugar composition (% w/w): glucosamine 36.7, glucose 32.3, rhamnose 25.4, xylose 1.7, and not identified sugar 3.9. The hydrogel formed by PGA and EPS fractions showed high swelling behavior, very good emulsifying and stabilizing properties, and good foaming ability. This is the first report for halophilic bacterium able to synthesize a polymer containing PGA fraction. The synthesized biopolymer shows an extremely high hydrophilicity, due to the simultaneous presence of PGA and EPS. The analysis of its functional properties and the presence of glucosamine in the highest proportion in EPS fraction clearly determine the potential of EP synthesized by C. canadensis 28 for application in the cosmetics industry.

  16. Halophilic Amylase from a Moderately Halophilic Micrococcus

    Science.gov (United States)

    Onishi, Hiroshi

    1972-01-01

    A moderately halophilic Micrococcus sp., isolated from unrefined solar salt, produced a considerable amount of extracellular dextrinogenic amylase when cultivated aerobically in media containing 1 to 3 m NaCl. The Micrococcus amylase had maximal activity at pH 6 to 7 in 1.4 to 2 m NaCl or KCl at 50 C. Calcium ion and a high concentration of NaCl or KCl were essential for activity and stability of the amylase. The salt response of the amylase depended greatly on the pH and temperature of the enzyme assay. PMID:5058445

  17. Color-Removal by Microorganisms Isolated from Human Hands

    Directory of Open Access Journals (Sweden)

    Tsukasa Ito

    2013-08-01

    Full Text Available Microorganisms are essential for human life. Microorganisms decompose the carbon compounds in dead animals and plants and convert them into carbon dioxide. Intestinal bacteria assist in food digestion. Some vitamins are produced by bacteria that live in the intestines. Sewage and industrial wastewater are treated by activated sludge composed of microbial communities. All of these are due to the ability of microbes to produce many enzymes that can degrade chemicals. How do teachers make students understand that microorganisms are always associated with humans, and that microorganisms have the ability to degrade chemicals? The presence of microorganisms on humans can be shown by incubating agar plates after they are touched by the hands of students. The ability of microorganisms to degrade chemicals can be shown by an analytical measurement of the degradation of chemicals. When the chemicals are dyes (colorants in water, microbial activity on degradation of dyes can be demonstrated by observing a decreasing degree of color as a result of the enzymatic activity (e.g., azoreductase. Dyes are widely used in the textile, food, and cosmetic industries. They are generally resistant to conventional biological wastewater treatment systems such as the activated sludge process (4. The discharge of wastewater containing dye pollutes surface water. The ability of microorganisms to decolorize and degrade dyes has been widely investigated to use for bioremediation purposes (5. The goal of this tip is to understand the presence of bacteria on human skin and the ability of bacteria to degrade colorant chemicals (decolorization. In this tip, students first cultivate and isolate bacteria on their hands, and then examine potential decolorization activity of each bacterium by observing the degree of color of the liquid in tubes in which bacteria isolated from students’ hands were inoculated. Decolorization activity of bacterial isolates from human skin has been

  18. Purification and Characterization of Haloalkaline, Organic Solvent Stable Xylanase from Newly Isolated Halophilic Bacterium-OKH

    Science.gov (United States)

    Sanghvi, Gaurav; Jivrajani, Mehul; Patel, Nirav; Jivrajani, Heta; Bhaskara, Govinal Badiger; Patel, Shivani

    2014-01-01

    A novel, alkali-tolerant halophilic bacterium-OKH with an ability to produce extracellular halophilic, alkali-tolerant, organic solvent stable, and moderately thermostable xylanase was isolated from salt salterns of Mithapur region, Gujarat, India. Identification of the bacterium was done based upon biochemical tests and 16S rRNA sequence. Maximum xylanase production was achieved at pH 9.0 and 37°C temperature in the medium containing 15% NaCl and 1% (w/v) corn cobs. Sugarcane bagasse and wheat straw also induce xylanase production when used as carbon source. The enzyme was active over a range of 0–25% sodium chloride examined in culture broth. The optimum xylanase activity was observed at 5% sodium chloride. Xylanase was purified with 25.81%-fold purification and 17.1% yield. Kinetic properties such as Km and Vmax were 4.2 mg/mL and 0.31 μmol/min/mL, respectively. The enzyme was stable at pH 6.0 and 50°C with 60% activity after 8 hours of incubation. Enzyme activity was enhanced by Ca2+, Mn2+, and Mg2+ but strongly inhibited by heavy metals such as Hg2+, Fe3+, Ni2+, and Zn2+. Xylanase was found to be stable in organic solvents like glutaraldehyde and isopropanol. The purified enzyme hydrolysed lignocellulosic substrates. Xylanase, purified from the halophilic bacterium-OKH, has potential biotechnological applications. PMID:27350996

  19. Isolation and characterization of two novel halotolerant Catechol 2, 3-dioxygenases from a halophilic bacterial consortium

    Science.gov (United States)

    Guo, Guang; Fang, Tingting; Wang, Chongyang; Huang, Yong; Tian, Fang; Cui, Qijia; Wang, Hui

    2015-12-01

    Study of enzymes in halophiles will help to understand the mechanism of aromatic hydrocarbons degradation in saline environment. In this study, two novel catechol 2,3-dioxygenases (C23O1 and C23O2) were cloned and overexpressed from a halophilic bacterial consortium enriched from an oil-contaminated saline soil. Phylogenetic analysis indicated that the novel C23Os and their relatives formed a new branch in subfamily I.2.A of extradiol dioxygenases and the sequence differences were further analyzed by amino acid sequence alignment. Two enzymes with the halotolerant feature were active over a range of 0-30% salinity and they performed more stable at high salinity than in the absence of salt. Surface electrostatic potential and amino acids composition calculation suggested high acidic residues content, accounting for their tolerance to high salinity. Moreover, two enzymes were further characterized. The enzymes activity both increased in the presence of Fe3+, Fe2+, Cu2+ and Al3+ and showed no significant inhibition by other tested metal ions. The optimal temperatures for the C23Os were 40 °C and 60 °C and their best substrates were catechol and 4-methylcatechol respectively. As the firstly isolated and characterized catechol dioxygenases from halophiles, the two halotolerant C23Os presented novel characteristics suggesting their potential application in aromatic hydrocarbons biodegradation.

  20. Antibiotic cytotoxic effects of microorganisms isolated from Jachymov uranium mines

    International Nuclear Information System (INIS)

    Fuska, J.; Fuskova, A.

    1982-01-01

    Microorganisms were isolated from old relinquished uranium mines in Jachymov; they had been growing for several decades in darkness in temperatures of 5 to 12 degC and relative humidity from 80 to 100%. The concentration of uranium salts in mine waters varied from 10 -4 to 10 -5 g.l -1 , that of Rn in the atmosphere was from 0.04 to 40 Bq.l -1 . Of 324 cultures, 18.8% inhibited the growth of Bacillus subtilis, Escherichia coli and Candida pseudotropicalis and 16.6% that of HeLa cells. The frequency of microorganisms inhibiting the growth of HeLa or Ehrlich ascites cells was markedly higher in this set of cultures than among microorganisms kept in culture collections or isolated from other natural habitats. About 10% of the isolated cultures were mycelia sterilia. The following antibiotics were isolated from microorganisms obtained from uranium mines: frequentin, vermiculin, vermicillin, vermistatin, cytostipin and duclauxin. (author)

  1. Antibiotic cytotoxic effects of microorganisms isolated from Jachymov uranium mines

    Energy Technology Data Exchange (ETDEWEB)

    Fuska, J.; Fuskova, A. (Slovenska Vysoka Skola Technicka, Bratislava (Czechoslovakia). Chemickotechnologicka Fakulta); Jilek, R. (Vyzkumny Ustav Veterinarniho Lekarstvi, Brno-Medlanky (Czechoslovakia))

    1982-01-01

    Microorganisms were isolated from old relinquished uranium mines in Jachymov; they had been growing for several decades in darkness in temperatures of 5 to 12 degC and relative humidity from 80 to 100%. The concentration of uranium salts in mine waters varied from 10/sup -4/ to 10/sup -5/ g.l/sup -1/, that of Rn in the atmosphere was from 0.04 to 40 Bq.l/sup -1/. Of 324 cultures, 18.8% inhibited the growth of Bacillus subtilis, Escherichia coli and Candida pseudotropicalis and 16.6% that of HeLa cells. The frequency of microorganisms inhibiting the growth of HeLa or Ehrlich ascites cells was markedly higher in this set of cultures than among microorganisms kept in culture collections or isolated from other natural habitats. About 10% of the isolated cultures were mycelia sterilia. The following antibiotics were isolated from microorganisms obtained from uranium mines: frequentin, vermiculin, vermicillin, vermistatin, cytostipin and duclauxin.

  2. Neptunium (V) Adsorption to a Halophilic Bacterium Under High Ionic Strength Conditions: A Surface Complexation Modeling Approach

    Energy Technology Data Exchange (ETDEWEB)

    Ams, David A [Los Alamos National Laboratory

    2012-06-11

    Rationale for experimental design: Np(V) -- important as analog for Pu(V) and for HLW scenarios; High ionic strength -- relevant to salt-based repositories such as the WIPP; Halophilic microorganisms -- representative of high ionic strength environments. For the first time showed: Significant adsorbant to halophilic microorganisms over entire pH range under high ionic strength conditions; Strong influence of ionic strength with increasing adsorption with increasing ionic strength (in contrast to trends of previous low ionic strength studies); Effect of aqueous Np(V) and bacterial surface site speciation on adsorption; and Developed thermodynamic models that can be incorporated into geochemical speciation models to aid in the prediction of the fate and transport of Np(V) in more complex systems.

  3. Evaluation of biodecolorization of the textile azo dye by halophilic archaea

    Directory of Open Access Journals (Sweden)

    Masoomeh Selseleh Hassan-Kiadehi

    2017-09-01

    Discussion and conclusion: In conclusion, our results indicate that halophilic archaea have very high potential to decolorize azo dyes. Regarding high amounts of salts in textile wastewaters, using such microorganisms which can tolerate the harsh environment in order to decolorize azo dyes, could be a new approach in this field.

  4. Halophilic Bacteria of Lunsu Produce an Array of Industrially Important Enzymes with Salt Tolerant Activity

    Directory of Open Access Journals (Sweden)

    Sonika Gupta

    2016-01-01

    Full Text Available The halophilic bacterial isolates SS1, SS2, SS3, SS5, and SS8 were characterized for production of industrially important enzymes like amylase, protease, lipase, and glutaminase. Halophilic bacterial isolates SS1 and SS3 exhibited salt dependent extracellular amylase and protease activities. Both the halophilic isolates SS1 and SS3 exhibited maximum amylase and protease activities in the presence of 1.5 and 1.0 M NaCl, respectively, with the optimum pH 8 and temperature 40°C. SS2 showed maximum extracellular protease and lipase activities in the presence of 0.75 M NaCl, at optimum pH of 7, and temperature 37°C. The glutaminase activity of SS3 increased with increase in concentration of NaCl up to 2.5 M. The optimum pH and temperature for L-glutaminase activity of SS3 was 8 and 40°C, respectively. The combined hydrolytic activities of these halophilic bacterial isolates can be used for bioconversion of organic materials to useful products.

  5. Halophilic Bacteria of Lunsu Produce an Array of Industrially Important Enzymes with Salt Tolerant Activity.

    Science.gov (United States)

    Gupta, Sonika; Sharma, Parul; Dev, Kamal; Sourirajan, Anuradha

    2016-01-01

    The halophilic bacterial isolates SS1, SS2, SS3, SS5, and SS8 were characterized for production of industrially important enzymes like amylase, protease, lipase, and glutaminase. Halophilic bacterial isolates SS1 and SS3 exhibited salt dependent extracellular amylase and protease activities. Both the halophilic isolates SS1 and SS3 exhibited maximum amylase and protease activities in the presence of 1.5 and 1.0 M NaCl, respectively, with the optimum pH 8 and temperature 40°C. SS2 showed maximum extracellular protease and lipase activities in the presence of 0.75 M NaCl, at optimum pH of 7, and temperature 37°C. The glutaminase activity of SS3 increased with increase in concentration of NaCl up to 2.5 M. The optimum pH and temperature for L-glutaminase activity of SS3 was 8 and 40°C, respectively. The combined hydrolytic activities of these halophilic bacterial isolates can be used for bioconversion of organic materials to useful products.

  6. Structural adaptation of extreme halophilic proteins through decrease of conserved hydrophobic contact surface

    Science.gov (United States)

    2011-01-01

    Background Halophiles are extremophilic microorganisms growing optimally at high salt concentrations. There are two strategies used by halophiles to maintain proper osmotic pressure in their cytoplasm: accumulation of molar concentrations of potassium and chloride with extensive adaptation of the intracellular macromolecules ("salt-in" strategy) or biosynthesis and/or accumulation of organic osmotic solutes ("osmolyte" strategy). Our work was aimed at contributing to the understanding of the shared molecular mechanisms of protein haloadaptation through a detailed and systematic comparison of a sample of several three-dimensional structures of halophilic and non-halophilic proteins. Structural differences observed between the "salt-in" and the mesophilic homologous proteins were contrasted to those observed between the "osmolyte" and mesophilic pairs. Results The results suggest that haloadaptation strategy in the presence of molar salt concentration, but not of osmolytes, necessitates a weakening of the hydrophobic interactions, in particular at the level of conserved hydrophobic contacts. Weakening of these interactions counterbalances their strengthening by the presence of salts in solution and may help the structure preventing aggregation and/or loss of function in hypersaline environments. Conclusions Considering the significant increase of biotechnology applications of halophiles, the understanding of halophilicity can provide the theoretical basis for the engineering of proteins of great interest because stable at concentrations of salts that cause the denaturation or aggregation of the majority of macromolecules. PMID:22192175

  7. Structural adaptation of extreme halophilic proteins through decrease of conserved hydrophobic contact surface

    Directory of Open Access Journals (Sweden)

    Siglioccolo Alessandro

    2011-12-01

    Full Text Available Abstract Background Halophiles are extremophilic microorganisms growing optimally at high salt concentrations. There are two strategies used by halophiles to maintain proper osmotic pressure in their cytoplasm: accumulation of molar concentrations of potassium and chloride with extensive adaptation of the intracellular macromolecules ("salt-in" strategy or biosynthesis and/or accumulation of organic osmotic solutes ("osmolyte" strategy. Our work was aimed at contributing to the understanding of the shared molecular mechanisms of protein haloadaptation through a detailed and systematic comparison of a sample of several three-dimensional structures of halophilic and non-halophilic proteins. Structural differences observed between the "salt-in" and the mesophilic homologous proteins were contrasted to those observed between the "osmolyte" and mesophilic pairs. Results The results suggest that haloadaptation strategy in the presence of molar salt concentration, but not of osmolytes, necessitates a weakening of the hydrophobic interactions, in particular at the level of conserved hydrophobic contacts. Weakening of these interactions counterbalances their strengthening by the presence of salts in solution and may help the structure preventing aggregation and/or loss of function in hypersaline environments. Conclusions Considering the significant increase of biotechnology applications of halophiles, the understanding of halophilicity can provide the theoretical basis for the engineering of proteins of great interest because stable at concentrations of salts that cause the denaturation or aggregation of the majority of macromolecules.

  8. Isolation of microorganisms for biological control the moniliophthora roreri

    OpenAIRE

    suarez contreras, liliana yanet; Rangel Riaño, Alba Luz

    2014-01-01

    Moniliophlhora roreri is the causal agent of cocoa Moniliasis, which produces losses of up to 60% of the crop, as it affects only its commercial product, the cob. Biological control appears as an alternative management, using endophytic microorganisms. The reason because of this research came up was that it was aimed to isolate microorganisms with antagonist potential for biological control towards the phytopathogen M. roreri in Norte de Santander. This is done through isolation and identifica...

  9. Use of a mixed culture strategy to isolate halophilic bacteria with antibacterial and cytotoxic activity from the Manaure solar saltern in Colombia.

    Science.gov (United States)

    Conde-Martínez, Natalia; Acosta-González, Alejandro; Díaz, Luis E; Tello, Edisson

    2017-12-08

    Water evaporation in solar salterns creates salinity gradients that promote the adaptation of microbial species to different salinities. This competitive habitat challenges the metabolic capabilities of microorganisms and promotes alterations in their production of secondary metabolites. Thus, solar salterns are a potentially important source of new natural products. In Colombia, the most important and representative solar saltern is located in Manaure (La Guajira) in the north of Colombia. The aim of this study was to develop an alternative screening strategy to select halophilic bacteria as producers of bioactive compounds from mixed microbial cultures rather than individual environmental isolates. Brine and sediment samples from different ponds (across a salinity gradient) were inoculated in seven different culture media to grow bacteria and archaea, allowing for a total of 40 different mixed cultures. An organic extract from each mixed culture was obtained and tested against multidrug resistant pathogens, including Klebsiella pneumoniae, vancomycin-resistant Enterococcus faecium, methicillin-resistant Staphylococcus aureus and Bacillus subtilis. In addition, the extracts were tested against two human cancer cell lines, cervical adenocarcinoma (SiHa) and lung carcinoma (A-549). Twenty-four of the forty extracts from mixed cultures obtained from brine and sediment samples from the Manaure solar saltern showed antibacterial activity against Bacillus subtilis. Two extracts, referred to as A1SM3-29 and A1SM3-36, were also active against a methicillin-resistant Staphylococcus aureus, with the latter extract also showing slight cytotoxic activity against the assayed human lung cancer cell line. From this mixed culture, nine isolates were cultivated, and their extracts were tested against the same pathogens, resulting in the identification of a Vibrio sp. strain (A1SM3-36-8) with antimicrobial activity that was similar to that observed for the mixed culture extract

  10. Structural changes in halophilic and non-halophilic proteases in response to chaotropic reagents.

    Science.gov (United States)

    Sinha, Rajeshwari; Khare, S K

    2014-08-01

    Halophilic enzymes have been established for their stability and catalytic abilities under harsh operational conditions. These have been documented to withstand denaturation at high temperature, pH, organic solvents, and chaotropic agents. However, this stability is modulated by salt. The present study targets an important aspect in understanding protein-urea/GdmCl interactions using proteases from halophilic Bacillus sp. EMB9 and non-halophilic subtilisin (Carlsberg) from Bacillus licheniformis as model systems. While, halophilic protease containing 1 % (w/v) NaCl (0.17 M) retained full activity towards urea (8 M), non-halophilic protease lost about 90 % activity under similar conditions. The secondary and tertiary structure were lost in non-halophilic but preserved for halophilic protein. This effect could be due to the possible charge screening and shielding of the protein surface by Ca(2+) and Na(+) ions rendering it stable against denaturation. The dialyzed halophilic protease almost behaved like the non-halophilic counterpart. Incorporation of NaCl (up to 5 %, w/v or 0.85 M) in dialyzed EMB9 protease containing urea/GdmCl, not only helped regain of proteolytic activity but also evaded denaturing action. Deciphering the basis of this salt modulated stability amidst a denaturing milieu will provide guidelines and templates for engineering stable proteins/enzymes for biotechnological applications.

  11. Halophilic Nuclease from a Moderately Halophilic Micrococcus varians

    Science.gov (United States)

    Kamekura, Masahiro; Onishi, Hiroshi

    1974-01-01

    The moderately halophilic bacterium Micrococcus varians, isolated from soy sauce mash, produced extracellular nuclease when cultivated aerobically in media containing 1 to 4 M NaCl or KCl. The enzyme, purified to an electrophoretically homogeneous state, had both ribonuclease and deoxyribonuclease activities. The nuclease had maximal activity in the presence of 2.9 M NaCl or 2.1 M KCl at 40 C. The enzymatic activity was lost by dialysis against low-salt buffer, whereas when the inactivated enzyme was dialyzed against 3.4 M NaCl buffer as much as 77% of the initial activity could be restored. Images PMID:4852218

  12. An experimental point of view on hydration/solvation in halophilic proteins.

    Science.gov (United States)

    Talon, Romain; Coquelle, Nicolas; Madern, Dominique; Girard, Eric

    2014-01-01

    Protein-solvent interactions govern the behaviors of proteins isolated from extreme halophiles. In this work, we compared the solvent envelopes of two orthologous tetrameric malate dehydrogenases (MalDHs) from halophilic and non-halophilic bacteria. The crystal structure of the MalDH from the non-halophilic bacterium Chloroflexus aurantiacus (Ca MalDH) solved, de novo, at 1.7 Å resolution exhibits numerous water molecules in its solvation shell. We observed that a large number of these water molecules are arranged in pentagonal polygons in the first hydration shell of Ca MalDH. Some of them are clustered in large networks, which cover non-polar amino acid surface. The crystal structure of MalDH from the extreme halophilic bacterium Salinibacter ruber (Sr) solved at 1.55 Å resolution shows that its surface is strongly enriched in acidic amino acids. The structural comparison of these two models is the first direct observation of the relative impact of acidic surface enrichment on the water structure organization between a halophilic protein and its non-adapted counterpart. The data show that surface acidic amino acids disrupt pentagonal water networks in the hydration shell. These crystallographic observations are discussed with respect to halophilic protein behaviors in solution.

  13. Isolation, cloning and characterization of an azoreductase from the halophilic bacterium Halomonas elongata.

    Science.gov (United States)

    Eslami, Maryam; Amoozegar, Mohammad Ali; Asad, Sedigheh

    2016-04-01

    Azo dyes are a major class of colorants used in various industries including textile, paper and food. These dyes are regarded as pollutant since they are not readily reduced under aerobic conditions. Halomonas elongata, a halophilic bacterium, has the ability to decolorize different mono and di-azo dyes in anoxic conditions. In this study the putative azoreductase gene of H. elongata, formerly annotated as acp, was isolated, heterologously expressed in Escherichia coli, purified and characterized. The gene product, AzoH, was found to have a molecular mass of 22 kDa. The enzyme requires NADH, as an electron donor for its activity. The apparent Km was 63 μM for NADH and 12 μM for methyl red as a mono-azo dye substrate. The specific activity for methyl red was 0.27 μmol min(-1)mg(-1). The optimum enzyme activity was achieved in 50mM sodium phosphate buffer at pH 6. Although increased salinity resulted in reduced activity, AzoH could decolorize azo dye at NaCl concentrations up to 15% (w/v). The enzyme was also shown to be able to decolorize remazol black B as a representative of di-azo dyes. This is the first report describing the sequence and activity of an azo-reducing enzyme from a halophilic bacterium. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Unique Features of Halophilic Proteins.

    Science.gov (United States)

    Arakawa, Tsutomu; Yamaguchi, Rui; Tokunaga, Hiroko; Tokunaga, Masao

    2017-01-01

    Proteins from moderate and extreme halophiles have unique characteristics. They are highly acidic and hydrophilic, similar to intrinsically disordered proteins. These characteristics make the halophilic proteins soluble in water and fold reversibly. In addition to reversible folding, the rate of refolding of halophilic proteins from denatured structure is generally slow, often taking several days, for example, for extremely halophilic proteins. This slow folding rate makes the halophilic proteins a novel model system for folding mechanism analysis. High solubility and reversible folding also make the halophilic proteins excellent fusion partners for soluble expression of recombinant proteins.

  15. Halomonas indalinina sp.nov., a moderately halophilic bacterium isolated from a solar saltern in Cabo de Gata, Al,eria, southern Spain

    NARCIS (Netherlands)

    Cabrera, A.; Aguilera, M.; Fuentes Enriquez de Salamanca, S.; Incerti, C.; Russell, N.J.; Ramos-Cormenzana, A.; Monteoliva-Sanchez, M.

    2007-01-01

    moderately halophilic bacterium, strain CG2.1T, isolated from a solar saltern at Cabo de Gata, a wildlife reserve located in the province of Almería, southern Spain, was subjected to a polyphasic taxonomic study. This organism was an aerobic, motile, Gram-negative rod that produced orange-pigmented

  16. Hans Georg Trüper (1936–2016 and His Contributions to Halophile Research

    Directory of Open Access Journals (Sweden)

    Aharon Oren

    2016-05-01

    Full Text Available Prof. Hans Georg Trüper, one of the most important scientists in the field of halophile research, passed away on 9 March 2016 at the age of 79. I here present a brief obituary with special emphasis on Prof. Trüper’s contributions to our understanding of the halophilic prokaryotes and their adaptations to life in hypersaline environments. He has pioneered the study of the halophilic anoxygenic phototrophic sulfur bacteria of the Ectothiorhodospira—Halorhodospira group. Some of the species he and his group isolated from hypersaline and haloalkaline environments have become model organisms for the study of the mechanisms of haloadaptation: the functions of three major organic compounds – glycine betaine, ectoine, and trehalose – known to serve as “compatible solutes” in halophilic members of the Bacteria domain, were discovered during studies of these anoxygenic phototrophs. Prof. Trüper’s studies of hypersaline alkaline environments in Egypt also led to the isolation of the first known extremely halophilic archaeon (Natronomonas pharaonis. The guest editors dedicate this special volume of Life to the memory of Prof. Hans Georg Trüper.

  17. Biogenic amines degradation by microorganisms isolated from cheese

    Directory of Open Access Journals (Sweden)

    Irena Butor

    2017-01-01

    Full Text Available The aim of this study was the isolation and characterization of microorganisms able to degrade biogenic amines and their identification. Individual microorganisms were obtained by isolation from commercially available foodstuffs and food produced in the technological laboratories of Faculty of Technology, Tomas Bata University in Zlín and subsequently identified by MALDI-TOF MS. The results of MALDI-TOF MS identification were verified by 16S rRNA sequenation. In this work was studied the ability of 5 bacterial strains positive to biogenic amines degradation isolated from dairy products to decrease biogenic amines content in vitro and quantified reduction in the concentration of biogenic amines tryptamine, β-phenylethylamine, putrescine, cadaverine, histamine and tyramine. The level of degradation (decrease of biogenic amines was determined on the base of the ability to grow in media with biogenic amines as the sole source carbon and nitrogen. The isolated strains with the ability of degradation of one or more biogenic amines were cultured in medium supplemented with relevant biogenic amines, the media derivatized with dansyl chloride and these amines separated by HPLC at a wavelength of 254 nm. From five tested strains identified as Bacillus subtilis, Bacillus pumilus, Enterobacter cloacae, Rhizobium radiobacter and Acinetobacter pitii, isolated from gouda type cheese, the greatest ability of degradation was observed in Bacillus subtilis, which was capable to degrade almost all amount of histamine, cadaverine and putrescine. Other four strains showed a lower rate of degradation than Bacillus subtilis, but the ability to degrade biogenic amines with these microorganisms was still significant.

  18. Isolation of Electrogenic Microorganisms with Potential to Reduce Hexavalent Chromium

    Directory of Open Access Journals (Sweden)

    Alexander Mora Collazos

    2017-01-01

    Full Text Available Isolation of cultivable microorganisms was made from the biofilm formed on the anode of a microbial fuel cell put into operation for 30 days; isolated microorganisms were evaluated for their ability to produce energy and reduce the hexavalent chromium Cr (VI. Five microorganisms were isolated, which were characterized by analysis of 16S rRNA gene, placing them in four bacterial genera: Exiguobacterium (CrMFC1, Acinetobacter (CrMFC2, Aeromonas (CrMFC3 and CrMFC5 and Serratia (CrMFC4. All isolates showed electrogenic activity and ability to reduce hexavalent chromium; the Acinetobacter CrMFC1 strain showed the best electrochemical performance registering a maximum power density of 18.61 mW/m2; the other strains showed values of maximum power density between 4.6 mW/m2and 7.1 mW/m2. Strains Aeromonas CrMFC5 and Exiguobacterium CrMFC1 showed the best rates of chromium reduction being able to reduce 100 % of the Cr (VI in less than 24 hours, the Aeromonas CrMFC5 strain was the most efficient, reducing 100 % of Cr (VI in 10 hours; the other strains reduced 100% of the contaminant after 28 to 30 hours. The microorganisms isolated in this study are hardly known for their electrogenic capacity and for reducing Cr (VI; however, show promise for their use in combined systems involving energy production system coupled to bioremediation of chromium contaminated water.

  19. Isolation, characterization and phylogenetic analysis of halophilic archaea from a salt mine in central Anatolia (Turkey).

    Science.gov (United States)

    Yildiz, Evrim; Ozcan, Birgul; Caliskan, Mahmut

    2012-01-01

    The haloarchaeal diversity of a salt mine, a natural cave in central Anatolia, was investigated using convential microbiological and molecular biology methods. Eight halophilic archaeal isolates selected based on their colony morphology and whole cell protein profiles were taxonomically classified on the basis of their morphological, physiological, biochemical properties, polar lipid and protein profiles and 16S rDNA sequences. From the 16S rDNA sequences comparisons it was established that the isolates CH2, CH3 and CHC resembled Halorubrum saccharovorum by 98.8%, 98.9% and 99.5%, respectively. There was a 99.7% similarity between the isolate CH11 and Halobacterium noricense and 99.2% between the isolate CHA1 and Haloarcula argentinensis. The isolate CH8K and CH8B revealed a similarity rate of 99.8% and 99.3% to Halococcus dombrowskii, respectively. It was concluded that the isolates named CH2, CH3 and CHC were clustered in the genus Halorubrum and that CHA1 and CH7 in the genus Haloarcula, CH8K and CH8B in the genus Halococcus and CH11 in the genus Halobacterium.

  20. Marinospirillum insulare sp. nov., a novel halophilic helical bacterium isolated from kusaya gravy.

    Science.gov (United States)

    Satomi, M; Kimura, B; Hayashi, M; Okuzumi, M; Fujii, T

    2004-01-01

    A novel species that belongs to the genus Marinospirillum is described on the basis of phenotypic characteristics, phylogenetic analysis of 16S rRNA and gyrB gene sequences and DNA-DNA hybridization. Four strains of helical, halophilic, Gram-negative, heterotrophic bacteria were isolated from kusaya gravy, which is fermented brine that is used for the production of traditional dried fish in the Izu Islands of Japan. All of the new isolates were motile by means of bipolar tuft flagella, of small cell size, coccoid-body-forming and aerophilic; it was concluded that they belong to the same bacterial species, based on DNA-DNA hybridization values (>70% DNA relatedness). DNA G+C contents of the new strains were 42-43 mol% and they had isoprenoid quinone Q-8 as the major component. Phylogenetic analysis of 16S rRNA gene sequences indicated that the new isolates were members of the genus Marinospirillum; sequence similarity of the new isolates to Marinospirillum minutulum, Marinospirillum megaterium and Marinospirillum alkaliphilum was 98.5, 98.2 and 95.2%, respectively. Phylogenetic analysis based on the gyrB gene indicated that the new isolates had enough phylogenetic distance from M. minutulum and M. megaterium to be regarded as different species, with 84.7 and 78.7% sequence similarity, respectively. DNA-DNA hybridization showed that the new isolates had <36% DNA relatedness to M. minutulum and M. megaterium, supporting the phylogenetic conclusion. Thus, a novel species is proposed: Marinospirillum insulare sp. nov. (type strain, KT=LMG 21802T=NBRC 100033T).

  1. Antibiotic Sensitivity Pattern of Microorganisms Isolated from ...

    African Journals Online (AJOL)

    Antibiotic sensitivity pattern of microorganisms isolated from smoked and frozen fishes sold in Benin and Warri metropolis were investigated. Adopting microbiological standard techniques, the results of the bacterial counts and fungal counts ranged from 5.4 x 106 (Ekpan market) to 25.1 x 106 (Ekpan market) and 1.1 x 105 ...

  2. Enhancement of Biodegradation of Palm Oil Mill Effluents by Local Isolated Microorganisms.

    Science.gov (United States)

    Soleimaninanadegani, Mohammadreza; Manshad, Soheila

    2014-01-01

    This study was designed to investigate the microorganisms associated with palm oil mill effluent (POME) in Johor Bahru state, Malaysia. Biodegradation of palm oil mill effluents (POME) was conducted to measure the discarded POME based on physicochemical quality. The bacteria that were isolated are Micrococcus species, Bacillus species, Pseudomonas species, and Staphylococcus aureus, while the fungi that were isolated are Aspergillus niger, Aspergillus fumigatus, Candida species, Fusarium species, Mucor species, and Penicillium species. The autoclaved and unautoclaved raw POME samples were incubated for 7 days and the activities of the microorganisms were observed each 12 hours. The supernatants of the digested POME were investigated for the removal of chemical oxygen demand (COD), color (ADMI), and biochemical oxygen demand (BOD) at the end of each digestion cycle. The results showed that the unautoclaved raw POME sample degraded better than the inoculated POME sample and this suggests that the microorganisms that are indigenous in the POME are more effective than the introduced microorganisms. This result, however, indicates the prospect of isolating indigenous microorganisms in the POME for effective biodegradation of POME. Moreover, the effective treatment of POME yields useful products such as reduction of BOD, COD, and color.

  3. Enhancement of Biodegradation of Palm Oil Mill Effluents by Local Isolated Microorganisms

    Science.gov (United States)

    Soleimaninanadegani, Mohammadreza

    2014-01-01

    This study was designed to investigate the microorganisms associated with palm oil mill effluent (POME) in Johor Bahru state, Malaysia. Biodegradation of palm oil mill effluents (POME) was conducted to measure the discarded POME based on physicochemical quality. The bacteria that were isolated are Micrococcus species, Bacillus species, Pseudomonas species, and Staphylococcus aureus, while the fungi that were isolated are Aspergillus niger, Aspergillus fumigatus, Candida species, Fusarium species, Mucor species, and Penicillium species. The autoclaved and unautoclaved raw POME samples were incubated for 7 days and the activities of the microorganisms were observed each 12 hours. The supernatants of the digested POME were investigated for the removal of chemical oxygen demand (COD), color (ADMI), and biochemical oxygen demand (BOD) at the end of each digestion cycle. The results showed that the unautoclaved raw POME sample degraded better than the inoculated POME sample and this suggests that the microorganisms that are indigenous in the POME are more effective than the introduced microorganisms. This result, however, indicates the prospect of isolating indigenous microorganisms in the POME for effective biodegradation of POME. Moreover, the effective treatment of POME yields useful products such as reduction of BOD, COD, and color. PMID:27433516

  4. Life under Multiple Extreme Conditions: Diversity and Physiology of the Halophilic Alkalithermophiles

    Science.gov (United States)

    Wiegel, Juergen

    2012-01-01

    Around the world, there are numerous alkaline, hypersaline environments that are heated either geothermally or through intense solar radiation. It was once thought that such harsh environments were inhospitable and incapable of supporting a variety of life. However, numerous culture-dependent and -independent studies revealed the presence of an extensive diversity of aerobic and anaerobic bacteria and archaea that survive and grow under these multiple harsh conditions. This diversity includes the halophilic alkalithermophiles, a novel group of polyextremophiles that require for growth and proliferation the multiple extremes of high salinity, alkaline pH, and elevated temperature. Life under these conditions undoubtedly involves the development of unique physiological characteristics, phenotypic properties, and adaptive mechanisms that enable control of membrane permeability, control of intracellular osmotic balance, and stability of the cell wall, intracellular proteins, and other cellular constituents. This minireview highlights the ecology and growth characteristics of the extremely halophilic alkalithermophiles that have been isolated thus far. Biochemical, metabolic, and physiological properties of the extremely halophilic alkalithermophiles are described, and their roles in resistance to the combined stressors of high salinity, alkaline pH, and high temperature are discussed. The isolation of halophilic alkalithermophiles broadens the physicochemical boundaries for life and extends the boundaries for the combinations of the maximum salinity, pH, and temperature that can support microbial growth. PMID:22492435

  5. Isolation, characterization and exploring biotechnological potential of halophilic archaea from salterns of western India.

    Science.gov (United States)

    Singh, Aparna; Singh, Anil Kumar

    2018-01-01

    Thirteen halophilic archaea were isolated from Kandla and Bhayander salt pans. These isolates were grouped into three different genera Halobacterium, Haloferax and Haloarcula based on morphological and biochemical characterization, polar lipid analysis, Amplified 16S rDNA restriction analysis (ARDRA) and 16S rDNA sequence analysis. Biochemical characterization suggested the ability of isolates to produce protease, amylase and poly-hydroxybutyrate (PHB) indicating their biotechnological potential. The isolates were further screened for the amount of extracellular protease produced. Halobacterium sp. SP1(1) showed significant protease production compared to other isolates. Protease producing ability of the isolate was influenced by several factors such as NaCl concentration, type of protein source, metal ions and surfactants, and presence of amino acid supplements in the production medium. Soybean flour, FeCl 3 and dicotylsulfosuccinate were found to increase protease production by 2.36, 1.54 and 1.26 folds, respectively compared to production in basal medium. Effect of organic solvents used in paints (n-decane, n-undecane and n-dodecane) was also investigated on protease production by the isolate. Protease production by Halobacterium sp. SP1(1) was enhanced by 1.2 folds in presence of n-decane compared to control. Furthermore, the ability of isolate to hydrolyse fish protein was investigated using three different edible fishes (Pomfret, Flat fish and Seer fish) as sole protein source. Pomfret was found to be a good protein source for protease production by the isolate. These results revealed that Halobacterium sp. SP1(1) may have potential for paint-based antifouling coating preparations and fish sauce preparation by virtue of its extracellular protease.

  6. Nesterenkonia sp. strain F, a halophilic bacterium producing acetone, butanol, and ethanol under aerobic conditions.

    Science.gov (United States)

    Amiri, Hamid; Azarbaijani, Reza; Parsa Yeganeh, Laleh; Shahzadeh Fazeli, Abolhassan; Tabatabaei, Meisam; Salekdeh, Ghasem Hosseini; Karimi, Keikhosro

    2016-01-04

    The moderately halophilic bacterium Nesterenkonia sp. strain F, which was isolated from Aran-Bidgol Lake (Iran), has the ability to produce acetone, butanol, and ethanol (ABE) as well as acetic and butyric acids under aerobic and anaerobic conditions. This result is the first report of ABE production with a wild microorganism from a family other than Clostridia and also the first halophilic species shown to produce butanol under aerobic cultivation. The cultivation of Nesterenkonia sp. strain F under anaerobic conditions with 50 g/l of glucose for 72 h resulted in the production of 105 mg/l of butanol, 122 mg/l of acetone, 0.2 g/l of acetic acid, and 2.5 g/l of butyric acid. Furthermore, the strain was cultivated on media with different glucose concentrations (20, 50, and 80 g/l) under aerobic and anaerobic conditions. Through fermentation with a 50 g/l initial glucose concentration under aerobic conditions, 66 mg/l of butanol, 125 mg/l of acetone, 291 mg/l of ethanol, 5.9 g/l of acetic acid, and 1.2 g/l of butyric acid were produced. The enzymes pertaining to the fermentation pathway in the strain were compared with the enzymes of Clostridium spp., and the metabolic pathway of fermentation used by Nesterenkonia sp. strain F was investigated.

  7. A comparison of liquid-holding recovery and photoreactivation in halophilic and non-halophilic bacteria

    International Nuclear Information System (INIS)

    Fitt, P.S.; Sharma, N.; Castellanos, G.

    1983-01-01

    The ability of the extreme halophile Halobacterium cutirubrum to recover from the effects of ultraviolet radiation during liquid holding in the dark in non-nutrient medium has been compared with that of (i) a moderately halophilic bacterium (NRC 41227) and (ii) Escherichia coli B. The photoreactivabilities of all three bacteria have also been studied. The extreme halophile was incapable of liquid-holding recovery in these conditions, in marked contrast to both E. coli B and the moderate halophile, and also failed to recover when held in nutrient medium in the dark. These results strongly support the hypothesis that H. cutirubrum lacks DNA excision repair. It was also found that ultraviolet-irradiated H. cutirubrum could be almost completely photoreactivated from any level of survival in the range 10 - 4 -80%, provided exposure to visible light was not delayed, whereas the moderate halophile resembled E. coli B and had a comparatively limited capacity for photoreactivation. (Auth.)

  8. Rate of biodegradation of crude oil by microorganisms isolated from ...

    African Journals Online (AJOL)

    The rate of biodegradation of crude oil by micro-organisms isolated from crude oil sludge environment in Eket, Akwa Ibom State of Nigeria was studied. Mineral salt medium supplemented with crude oil was used and three most abundant species isolated from a crude oil sludged soil - Micrococcus varians, Bacillus subtilis ...

  9. Antagonistic interactions and production of halocin antimicrobial peptides among extremely halophilic prokaryotes isolated from the solar saltern of Sfax, Tunisia.

    Science.gov (United States)

    Ghanmi, Fadoua; Carré-Mlouka, Alyssa; Vandervennet, Manon; Boujelben, Ines; Frikha, Doniez; Ayadi, Habib; Peduzzi, Jean; Rebuffat, Sylvie; Maalej, Sami

    2016-05-01

    Thirty-five extremely halophilic microbial strains isolated from crystallizer (TS18) and non-crystallizer (M1) ponds in the Sfax solar saltern in Tunisia were examined for their ability to exert antimicrobial activity. Antagonistic assays resulted in the selection of eleven strains that displayed such antimicrobial activity and they were further characterized. Three cases of cross-domain inhibition (archaea/bacteria or bacteria/archaea) were observed. Four archaeal strains exerted antimicrobial activity against several other strains. Three strains, for which several lines of evidence suggested the antimicrobial activity was, at least in part, due to peptide/protein agents (Halobacterium salinarum ETD5, Hbt. salinarum ETD8, and Haloterrigena thermotolerans SS1R12), were studied further. Optimal culture conditions for growth and antimicrobial production were determined. Using DNA amplification with specific primers, sequencing and RT-PCR analysis, Hbt. salinarum ETD5 and Hbt. salinarum ETD8 were shown to encode and express halocin S8, a hydrophobic antimicrobial peptide targeting halophilic archaea. Although the gene encoding halocin H4 was amplified from the genome of Htg. thermotolerans SS1R12, no transcript could be detected and the antimicrobial activity was most likely due to multiple antimicrobial compounds. This is also the first report that points to four different strains isolated from different geographical locations with the capacity to produce identical halocin S8 proteins.

  10. Isolation and screening of microorganisms from a gari fermentation ...

    African Journals Online (AJOL)

    Isolation and screening of microorganisms from a gari fermentation process for starter culture development. Vinodh A Edward, Moutairou Egounlety, Melanie Huch, Petrus J Van Zyl, Suren Singh, Naledzani D Nesengani, Vetja M Haakuria, Charles MAP Franz ...

  11. Halomonas sp. BS4, A biosurfactant producing halophilic bacterium isolated from solar salt works in India and their biomedical importance

    OpenAIRE

    Donio, Mariathason Birdilla Selva; Ronica, Fernando Arul; Viji, Vijayaragavan Thanga; Velmurugan, Subramanian; Jenifer, John Selesteen Charles Adlin; Michaelbabu, Mariavincent; Dhar, Prasenjit; Citarasu, Thavasimuthu

    2013-01-01

    Halophilic bacteria were isolated from Thamaraikulam solar salt works in India. After routine biosurfactant screening by various methods, the biosurfactant producing bacteria, Halomonas sp BS4 was confirmed by 16?S rRNA sequencing. The growth optimization of Halomonas sp BS4 revealed their optimum growth at 8% NaCl and 6-8?pH in the growth medium. Further the partially purified biosurfactants were characterized by TLC, FTIR and GC-MS analysis. GC-MS results revealed that, the partial purified...

  12. Characterization of Microorganisms Isolated from Petroleum Hydrocarbon Polluted Soil

    Directory of Open Access Journals (Sweden)

    Adriana Criste

    2016-02-01

    Full Text Available Bioremediation has received a great deal of attention, and bacteria isolated from polluted soil can be usedin that process. In this study, we performed an evaluation of the physiological groups of microorganisms fromsoil contaminated with petroleum. Bacterial strains were isolated from contaminated soil using the selectiveenrichment technique. Minimal Salt Media was used for serial dilutions to determine viable cell count. Thenumber of total viable cells and different types of microorganisms in the original sample was determined by serialdilution, agar plating procedure using selective media. The plates were incubated at 300C for 24-72 hours. Distinctcolonies growing on each plate were selected, and stored at freezing temperatures. The bacterial colonies werethen identified by Gram staining and biochemical tests. Following our research, it was observed that although thetotal microbial load of soil is relatively close in value, there are differences regarding the physiological group ofmicroorganisms. In the oil contaminated soil sample the largest group of microorganisms was the nitrous nitrifyingbacteria followed by nitrate bacteria. All bacterial strains that were isolated from soil samples contaminated withhydrocarbons but also the Pseudomonas putida and Bacillus subtillis strains can use diesel fuel as a food source.With the increase of diesel fuel concentration from culture medium, the majority of the bacterial strains that wereused in our experiments showed an increased value of absorbance. This fact suggests that these strains can be usedin bioremediation processes.

  13. Potential and limits of Raman spectroscopy for carotenoid detection in microorganisms: implications for astrobiology

    Science.gov (United States)

    Jehlička, Jan; Edwards, Howell G. M.; Osterrothová, Kateřina; Novotná, Julie; Nedbalová, Linda; Kopecký, Jiří; Němec, Ivan; Oren, Aharon

    2014-01-01

    In this paper, it is demonstrated how Raman spectroscopy can be used to detect different carotenoids as possible biomarkers in various groups of microorganisms. The question which arose from previous studies concerns the level of unambiguity of discriminating carotenoids using common Raman microspectrometers. A series of laboratory-grown microorganisms of different taxonomic affiliation was investigated, such as halophilic heterotrophic bacteria, cyanobacteria, the anoxygenic phototrophs, the non-halophilic heterotrophs as well as eukaryotes (Ochrophyta, Rhodophyta and Chlorophyta). The data presented show that Raman spectroscopy is a suitable tool to assess the presence of carotenoids of these organisms in cultures. Comparison is made with the high-performance liquid chromatography approach of analysing pigments in extracts. Direct measurements on cultures provide fast and reliable identification of the pigments. Some of the carotenoids studied are proposed as tracers for halophiles, in contrast with others which can be considered as biomarkers of other genera. The limits of application of Raman spectroscopy are discussed for a few cases where the current Raman spectroscopic approach does not allow discriminating structurally very similar carotenoids. The database reported can be used for applications in geobiology and exobiology for the detection of pigment signals in natural settings. PMID:25368348

  14. Halophilic Bacteria as a Source of Novel Hydrolytic Enzymes

    Science.gov (United States)

    de Lourdes Moreno, María; Pérez, Dolores; García, María Teresa; Mellado, Encarnación

    2013-01-01

    Hydrolases constitute a class of enzymes widely distributed in nature from bacteria to higher eukaryotes. The halotolerance of many enzymes derived from halophilic bacteria can be exploited wherever enzymatic transformations are required to function under physical and chemical conditions, such as in the presence of organic solvents and extremes in temperature and salt content. In recent years, different screening programs have been performed in saline habitats in order to isolate and characterize novel enzymatic activities with different properties to those of conventional enzymes. Several halophilic hydrolases have been described, including amylases, lipases and proteases, and then used for biotechnological applications. Moreover, the discovery of biopolymer-degrading enzymes offers a new solution for the treatment of oilfield waste, where high temperature and salinity are typically found, while providing valuable information about heterotrophic processes in saline environments. In this work, we describe the results obtained in different screening programs specially focused on the diversity of halophiles showing hydrolytic activities in saline and hypersaline habitats, including the description of enzymes with special biochemical properties. The intracellular lipolytic enzyme LipBL, produced by the moderately halophilic bacterium Marinobacter lipolyticus, showed advantages over other lipases, being an enzyme active over a wide range of pH values and temperatures. The immobilized LipBL derivatives obtained and tested in regio- and enantioselective reactions, showed an excellent behavior in the production of free polyunsaturated fatty acids (PUFAs). On the other hand, the extremely halophilic bacterium, Salicola marasensis sp. IC10 showing lipase and protease activities, was studied for its ability to produce promising enzymes in terms of its resistance to temperature and salinity. PMID:25371331

  15. Halophilic Bacteria as a Source of Novel Hydrolytic Enzymes

    Directory of Open Access Journals (Sweden)

    Encarnación Mellado

    2013-01-01

    Full Text Available Hydrolases constitute a class of enzymes widely distributed in nature from bacteria to higher eukaryotes. The halotolerance of many enzymes derived from halophilic bacteria can be exploited wherever enzymatic transformations are required to function under physical and chemical conditions, such as in the presence of organic solvents and extremes in temperature and salt content. In recent years, different screening programs have been performed in saline habitats in order to isolate and characterize novel enzymatic activities with different properties to those of conventional enzymes. Several halophilic hydrolases have been described, including amylases, lipases and proteases, and then used for biotechnological applications. Moreover, the discovery of biopolymer-degrading enzymes offers a new solution for the treatment of oilfield waste, where high temperature and salinity are typically found, while providing valuable information about heterotrophic processes in saline environments. In this work, we describe the results obtained in different screening programs specially focused on the diversity of halophiles showing hydrolytic activities in saline and hypersaline habitats, including the description of enzymes with special biochemical properties. The intracellular lipolytic enzyme LipBL, produced by the moderately halophilic bacterium Marinobacter lipolyticus, showed advantages over other lipases, being an enzyme active over a wide range of pH values and temperatures. The immobilized LipBL derivatives obtained and tested in regio- and enantioselective reactions, showed an excellent behavior in the production of free polyunsaturated fatty acids (PUFAs. On the other hand, the extremely halophilic bacterium, Salicola marasensis sp. IC10 showing lipase and protease activities, was studied for its ability to produce promising enzymes in terms of its resistance to temperature and salinity.

  16. Antibacterial Effect of Copper on Microorganisms Isolated from Bovine Mastitis

    Science.gov (United States)

    Reyes-Jara, Angelica; Cordero, Ninoska; Aguirre, Juan; Troncoso, Miriam; Figueroa, Guillermo

    2016-01-01

    The antimicrobial properties of copper have been recognized for several years; applying these properties to the prevention of diseases such as bovine mastitis is a new area of research. The aim of the present study was to evaluate in vitro the antimicrobial activity of copper on bacteria isolated from subclinical and clinical mastitis milk samples from two regions in Chile. A total of 327 microorganisms were recovered between March and September 2013, with different prevalence by sample origin (25 and 75% from the central and southern regions of Chile, respectively). In the central region, Escherichia coli and coagulase negative Staphylococci (CNS) were the most frequently detected in clinical mastitis cases (33%), while in the southern region S. uberis, S. aureus, and CNS were detected with frequencies of 22, 21, and 18%, respectively. Antibiotic susceptibility studies revealed that 34% of isolates were resistant to one or more antibiotics and the resistance profile was different between bacterial species and origins of isolation of the bacteria. The minimum inhibitory concentration of copper (MIC-Cu) was evaluated in all the isolates; results revealed that a concentration as low as 250 ppm copper was able to inhibit the great majority of microorganisms analyzed (65% of isolates). The remaining isolates showed a MIC-Cu between 375 and 700 ppm copper, and no growth was observed at 1000 ppm. A linear relationship was found between the logarithm of viable bacteria number and time of contact with copper. With the application of the same concentration of copper (250 ppm), CNS showed the highest tolerance to copper, followed by S. uberis and S. aureus; the least resistant was E. coli. Based on these in vitro results, copper preparations could represent a good alternative to dipping solutions, aimed at preventing the presence and multiplication of potentially pathogenic microorganisms involved in bovine mastitis disease. PMID:27199953

  17. Diversity and enumeration of halophilic and alkaliphilic bacteria in Spanish-style green table-olive fermentations.

    Science.gov (United States)

    Lucena-Padrós, Helena; Ruiz-Barba, José Luis

    2016-02-01

    The presence and enumeration of halophilic and alkaliphilic bacteria in Spanish-style table-olive fermentations was studied. Twenty 10-tonne fermenters at two large manufacturing companies in Spain, previously studied through both culture dependent and independent (PCR-DGGE) methodologies, were selected. Virtually all this microbiota was isolated during the initial fermentation stage. A total of 203 isolates were obtained and identified based on 16S rRNA gene sequences. They belonged to 13 bacterial species, included in 11 genera. It was noticeable the abundance of halophilic and alkaliphilic lactic acid bacteria (HALAB). These HALAB belonged to the three genera of this group: Alkalibacterium, Marinilactibacillus and Halolactibacillus. Ten bacterial species were isolated for the first time from table olive fermentations, including the genera Amphibacillus, Natronobacillus, Catenococcus and Streptohalobacillus. The isolates were genotyped through RAPD and clustered in a dendrogram where 65 distinct strains were identified. Biodiversity indexes found statistically significant differences between both patios regarding genotype richness, diversity and dominance. However, Jaccard similarity index suggested that the halophilic/alkaliphilic microbiota in both patios was more similar than the overall microbiota at the initial fermentation stage. Thus, up to 7 genotypes of 6 different species were shared, suggesting adaptation of some strains to this fermentation stage. Morisita-Horn similarity index indicated a high level of codominance of the same species in both patios. Halophilic and alkaliphilic bacteria, especially HALAB, appeared to be part of the characteristic microbiota at the initial stage of this table-olive fermentation, and they could contribute to the conditioning of the fermenting brines in readiness for growth of common lactic acid bacteria. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. Useful halophilic, thermostable and ionic liquids tolerant cellulases

    Science.gov (United States)

    Zhang, Tao; Datta, Supratim; Simmons, Blake A.; Rubin, Edward M.

    2016-06-28

    The present invention provides for an isolated or recombinant polypeptide comprising an amino acid sequence having at least 70% identity with the amino acid sequence of a Halorhabdus utahensis cellulase, such as Hu-CBH1, wherein said amino acid sequence has a halophilic thermostable and/or thermophilic cellobiohydrolase (CBH) activity. In some embodiments, the polypeptide has a CBH activity that is resistant to up to about 20% of ionic liquids. The present invention also provides for compositions comprising and methods using the isolated or recombinant polypeptide.

  19. Complete genome of Martelella sp. AD-3, a moderately halophilic polycyclic aromatic hydrocarbons-degrading bacterium.

    Science.gov (United States)

    Cui, Changzheng; Li, Zhijie; Qian, Jiangchao; Shi, Jie; Huang, Ling; Tang, Hongzhi; Chen, Xin; Lin, Kuangfei; Xu, Ping; Liu, Yongdi

    2016-05-10

    Martelella sp. strain AD-3, a moderate halophilic bacterium, was isolated from a petroleum-contaminated soil with high salinity in China. Here, we report the complete genome of strain AD-3, which contains one circular chromosome and two circular plasmids. An array of genes related to metabolism of polycyclic aromatic hydrocarbons and halophilic mechanism in this bacterium was identified by the whole genome analysis. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Halophiles, coming stars for industrial biotechnology.

    Science.gov (United States)

    Yin, Jin; Chen, Jin-Chun; Wu, Qiong; Chen, Guo-Qiang

    2015-11-15

    Industrial biotechnology aims to produce chemicals, materials and biofuels to ease the challenges of shortage on petroleum. However, due to the disadvantages of bioprocesses including energy consuming sterilization, high fresh water consumption, discontinuous fermentation to avoid microbial contamination, highly expensive stainless steel fermentation facilities and competing substrates for human consumption, industrial biotechnology is less competitive compared with chemical processes. Recently, halophiles have shown promises to overcome these shortcomings. Due to their unique halophilic properties, some halophiles are able to grow in high pH and high NaCl containing medium under higher temperature, allowing fermentation processes to run contamination free under unsterile conditions and continuous way. At the same time, genetic manipulation methods have been developed for halophiles. So far, halophiles have been used to produce bioplastics polyhydroxyalkanoates (PHA), ectoines, enzymes, and bio-surfactants. Increasing effects have been made to develop halophiles into a low cost platform for bioprocessing with advantages of low energy, less fresh water consumption, low fixed capital investment, and continuous production. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Isolation of microorganisms with capability to degrade polycyclic aromatic hydrocarbons (PATH )

    International Nuclear Information System (INIS)

    Vargas, M.C; Ramirez, N.E; Rueda, S.M; Sanchez, F.N

    1996-01-01

    This paper summarizes a work conducted on the isolation of microorganisms of contaminated sediments with a high percentage of hydrocarbons aromatic polynuclear (Polynuclear Aromatic Hydrocarbons, PAHS) The methodology involved two selection systems called fast route and slow route in which exposure periods and contaminant concentrations are the key determinants. The microorganisms isolated through the slow route system are more likely to be successful in degrading high molecular weight PAH'S. The six strains obtained through the fast route system were able to grow on low molecular weight PAH's showing preference towards the first four compounds of the sixteen demanded by the EPA (Environmental Protection Agency)

  2. DNA Repair and Photoprotection: Mechanisms of Overcoming Environmental Ultraviolet Radiation Exposure in Halophilic Archaea

    OpenAIRE

    Daniel L. Jones; Bonnie K. Baxter

    2017-01-01

    Halophilic archaea push the limits of life at several extremes. In particular, they are noted for their biochemical strategies in dealing with osmotic stress, low water activity and cycles of desiccation in their hypersaline environments. Another feature common to their habitats is intense ultraviolet (UV) radiation, which is a challenge that microorganisms must overcome. The consequences of high UV exposure include DNA lesions arising directly from bond rearrangement of adjacent bipyrimidine...

  3. Taxonomic analysis of extremely halophilic archaea isolated from 56-years-old dead sea brine samples.

    Science.gov (United States)

    Arahal, D R; Gutiérrez, M C; Volcani, B E; Ventosa, A

    2000-10-01

    A taxonomic study comprising both phenotypic and genotypic characterization, has been carried out on a total of 158 extremely halophilic aerobic archaeal strains. These strains were isolated from enrichments prepared from Dead Sea water samples dating from 1936 that were collected by B. E. Volcani for the demonstration of microbial life in the Dead Sea. The isolates were examined for 126 morphological, physiological, biochemical and nutritional tests. Numerical analysis of the data, by using the S(J) coefficient and UPGMA clustering method, showed that the isolates clustered into six phenons. Twenty-two out of the 158 strains used in this study were characterized previously (ARAHAL et al., 1996) and were placed into five phenotypic groups. The genotypic study included both the determination of the guanineplus-cytosine content of the DNA and DNA-DNA hybridization studies. For this purpose, representative strains from the six phenons were chosen. These groups were found to represent some members of three different genera - Haloarcula (phenons A, B, and C), Haloferax (phenons D and E) and Halobacterium (phenon F) - of the family Halobacteriaceae, some of them never reported to occur in the Dead Sea, such as Haloarcula hispanica, while Haloferax volcanii (phenons D and E) was described in the Dead Sea by studies carried out several decades later than Volcani's work.

  4. Noncontiguous finished genome sequence and description of Planococcus massiliensis sp. nov., a moderately halophilic bacterium isolated from the human gut

    Directory of Open Access Journals (Sweden)

    E.H. Seck

    2016-03-01

    Full Text Available We propose the main phenotypic characteristics and the complete genome sequence and annotation of Planococcus massiliensis strain ES2T (= CSUR P1103 = DSM 28915, the type strain of P. massiliensis sp. nov., isolated from a faeces sample collected from a healthy Senegalese man. It is an aerobic, Gram-positive, moderately halophilic, motile and rod-shaped bacterium. The 3 357 017 bp long genome exhibits a G+C content of 46.0% and contains 3357 protein-coding genes and 48 RNA genes.

  5. Production of surfactant and detergent-stable, halophilic, and alkalitolerant alpha-amylase by a moderately halophilic Bacillus sp. Strain TSCVKK.

    Science.gov (United States)

    Kiran, Kondepudi Kanthi; Chandra, T S

    2008-01-01

    A moderately halophilic alkalitolerant Bacillus sp. Strain TSCVKK, with an ability to produce extracellular halophilic, alkalitolerant, surfactant, and detergent-stable alpha-amylase was isolated from soil samples obtained from a salt-manufacturing industry in Chennai. The culture conditions for higher amylase production were optimized with respect to NaCl, substrate, pH, and temperature. Maximum amylase production of 592 mU/ml was achieved in the medium at 48 h with 10% NaCl, 1% dextrin, 0.4% yeast extract, 0.2% tryptone, and 0.2% CaCl(2) at pH 8.0 at 30 degrees C. The enzyme activity in the culture supernatant was highest with 10% NaCl at pH 7.5 and 55 degrees C. The amylase that was partially purified by acetone precipitation was highly stable in various surfactants and detergents. Glucose, maltose, and maltooligosaccharides were the main end products of starch hydrolysis indicating that it is an alpha-amylase.

  6. Support vector machine with a Pearson VII function kernel for discriminating halophilic and non-halophilic proteins.

    Science.gov (United States)

    Zhang, Guangya; Ge, Huihua

    2013-10-01

    Understanding of proteins adaptive to hypersaline environment and identifying them is a challenging task and would help to design stable proteins. Here, we have systematically analyzed the normalized amino acid compositions of 2121 halophilic and 2400 non-halophilic proteins. The results showed that halophilic protein contained more Asp at the expense of Lys, Ile, Cys and Met, fewer small and hydrophobic residues, and showed a large excess of acidic over basic amino acids. Then, we introduce a support vector machine method to discriminate the halophilic and non-halophilic proteins, by using a novel Pearson VII universal function based kernel. In the three validation check methods, it achieved an overall accuracy of 97.7%, 91.7% and 86.9% and outperformed other machine learning algorithms. We also address the influence of protein size on prediction accuracy and found the worse performance for small size proteins might be some significant residues (Cys and Lys) were missing in the proteins. Copyright © 2013 The Authors. Published by Elsevier Ltd.. All rights reserved.

  7. Lentibacillus amyloliquefaciens sp. nov., a halophilic bacterium isolated from saline sediment sample.

    Science.gov (United States)

    Wang, Jing-Li; Ma, Ke-Dong; Wang, Yan-Wei; Wang, Hui-Min; Li, Yan-Bin; Zhou, Shan; Chen, Xiao-Rong; Kong, De-Long; Guo, Xiang; He, Ming-Xiong; Ruan, Zhi-Yong

    2016-02-01

    A Gram-stain positive, non-motile, non-sporogenous, aerobic, rod-shaped and halophilic bacterium, designated LAM0015(T), was isolated from a saline sediment sample collected from Yantai City in China. The isolate was found to be able to grow at NaCl concentrations of 5-25 % (w/v) (optimum: 7-12 %), 15-45 °C (optimum: 35 °C) and pH 5.0-9.0 (optimum: 7.0). The major fatty acids were determined to be anteiso-C15:0 and anteiso-C17:0. The predominant respiratory quinone was identified as MK-7. The cell wall peptidoglycan was determined to contain meso-diaminopimelic acid. The polar lipids were found to be diphosphatidyglycerol, phosphatidylglycerol, five phospholipids and one glycolipid. The DNA G+C content was 43.1 mol% as determined by the T m method. Analysis of the 16S rRNA gene sequence indicated that the isolate belongs within the genus Lentibacillus and is closely related to Lentibacillus persicus DSM 22530(T), Lentibacillus salicampi JCM 11462(T) and Lentibacillus jeotgali JCM 15795(T) with 97.3, 96.7 and 96.4 % sequence similarity, respectively. The DNA-DNA hybridization value between LAM0015(T) and L. persicus DSM 22530(T) was 51.2 ± 1.4 %. Based on its phenotypic, phylogenetic and chemotaxonomic characteristics, strain LAM0015(T) is concluded to represent a novel species of the genus Lentibacillus, for which the name Lentibacillus amyloliquefaciens sp. nov. is proposed. The type strain is LAM0015(T) (=ACCC 06401(T) = JCM 19838(T)).

  8. Halophilic and halotolerant actinomycetes from a marine saltern of Goa, India producing anti-bacterial metabolites.

    Science.gov (United States)

    Ballav, Shuvankar; Kerkar, Savita; Thomas, Sabu; Augustine, Nimmy

    2015-03-01

    Marine salterns are estuarine ecosystems in Goa, receiving inputs from riverine and marine waters. The Salinity fluctuates between 0 and 300 psu which makes it a conducive niche for salt tolerant and salt loving Actinomycetales. Halotolerant and halophilic Actinomycetales producing anti-bacterial metabolites were studied from crystallizer pond sediments of Ribandar saltern, Goa. Three media viz. Starch casein, R2A and Inorganic salt starch agar at four different salinities (35, 50, 75 and 100 psu) were used for isolation. R2A agar at 35 psu was the most preferred by hypersaline actinomycetes. The dominant group was halotolerant Streptomyces spp. others being rare actinomycetes viz. Nocardiopsis, Micromonospora and Kocuria spp. More than 50% of the isolates showed anti-bacterial activity against one or more of the fifteen human pathogens tested. Eight strains from 4 genera showed consistent anti-bacterial activity and studied in detail. Most halotolerant isolates grew from 0 to 75 psu, with optimum antibiotic production at 35 psu whereas halophiles grew at 20 to 100 psu with optimum antibiotic production at 35 psu. Four Streptomyces strains showed multiple inhibition against test organisms while four rare actinomycetes were specific in their inhibitory activity. This is the first report of a halophilic Kocuria sp., Nocardiopsis sp., and halotolerant Micromonospora sp. producing anti-bacterial compound(s) against Staphylococcus aureus, Staphylococcus citreus, and Vibrio cholerae, respectively. Sequential extraction with varying polarity of organic solvents showed that the extracts inhibited different test pathogens. These results suggest that halophilic and halotolerant actinomycetes from marine salterns are a potential source of anti-bacterial compounds. Copyright © 2014 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  9. Isolation and identification of the microorganisms most prevalent in ...

    African Journals Online (AJOL)

    Infections of the external eye account for a significant percentage of ocular inflammations, some of which lead to visual losses as result of corneal involvement. This study purely isolated and identified the microorganisms most prevalent in external eye infections in Owerri urban (as seen Mercy Eye clinic). With the aid of ...

  10. Salty sisters: The women of halophiles

    Directory of Open Access Journals (Sweden)

    Bonnie K. Baxter

    2014-06-01

    Full Text Available A history of halophile research reveals the commitment of scientists to uncovering the secrets of the limits of life, in particular life in high salt concentration and under extreme osmotic pressure. During the last 40 years, halophile scientists have indeed made important contributions to extremophile research, and prior international halophiles congresses have documented both the historical and the current work. During this period of salty discoveries, female scientists, in general, have grown in number worldwide. But those who worked in the field when there were small numbers of women sometimes saw their important contributions overshadowed by their male counterparts. Recent studies suggest that modern female scientists experience gender bias in matters such as conference invitations and even representation among full professors. In the field of halophilic microbiology, what is the impact of gender bias? How has the participation of women changed over time? What do women uniquely contribute to this field? What are factors that impact current female scientists to a greater degree? This essay emphasizes the herstory (not history of halophile discovery.

  11. Copper-resistant halophilic bacterium isolated from the polluted Maruit Lake, Egypt.

    Science.gov (United States)

    Osman, O; Tanguichi, H; Ikeda, K; Park, P; Tanabe-Hosoi, S; Nagata, S

    2010-04-01

    To isolate and characterize copper-resistant halophilic bacteria from the polluted Maruit Lake, Egypt and identify the role of plasmids in toxic metal resistance. We isolated strain MA2, showing high copper resistance up to the 1.5 mmol l(-1) concentration; it was also resistant to other metals such as nickel, cobalt and zinc and a group of antibiotics. Partial 16S rRNA analysis revealed that strain MA2 belonged to the genus Halomonas. Copper uptake, measured by atomic absorption spectrophotometery, was higher in the absence of NaCl than in the presence of 0.5-1.0 mol l(-1) NaCl during 5-15 min of incubation. Cell fractionation and electron microscopic observation clarified that most of the copper accumulated in the outer membrane and periplasmic fractions of the cells. Plasmid screening yielded two plasmids: pMA21 (11 kb) and pMA22 (5 kb). Plasmid curing resulted in a strain that lost both the plasmids and was sensitive to cobalt and chromate but not copper, nickel and zinc. This cured strain also showed weak growth in the presence of 0.5-1.0 mol l(-1) NaCl. Partial sequencing of both plasmids led to the identification of different toxic metals transporters but copper transporters were not identified. The highest cell viability was found in the presence of 1.0 mol l(-1) NaCl at different copper concentrations, and copper uptake was optimal in the absence of NaCl. Plasmid pMA21 encoded chromate, cobalt, zinc and cadmium transporters, whereas pMA22 encoded specific zinc and RND (resistance, nodulation, cell division) efflux transporters as well as different kinds of metabolic enzymes. Copper resistance was mainly incorporated in the chromosome. Strain MA2 is a fast and efficient tool for copper bioremediation and the isolated plasmids show significant characteristics of both toxic metal and antibiotic resistance.

  12. Subsurface Halophilic Microbial Communities in the Hyperarid Core of the Atacama Desert: An Analog for Possible Subsurface Life in Regolith on Mars

    Science.gov (United States)

    Oren, A.; Warren-Rhodes, K.; Rainey, F. T.; Ewing, S.; McKay, C. P.

    2003-12-01

    The Atacama Desert in its driest portion provides an interesting analog for possible past or present life in the Martian regolith. In the hyperarid core of the Atacama, surface soils are virtually abiotic, with no plants and "near sterile" concentrations of heterotrophic bacteria (i.e., exceedingly low densities of approximately 100 colony forming units per gram soil). The dearth of microbial life at the surface is likely maintained through extremely low water availability, low organic content and the highly oxidizing nature of the soil. In marked contrast to the surface, however, extremely halophilic microorganisms exist in salt layers 1.2-1.5m below the surface. Mineralogical analyses indicate the layers are predominantly halite (70% NaCl) but also contain sodium nitrate (5% NaNO3). Culturing and polar lipid analyses suggest the halophiles are archaeal Halobacterium-like motile rods. Microclimate monitoring at 1m indicates a soil relative humidity of 20% which is stable year-round even during decadal rain events such as that experienced in July 2002. This suggests the layers are isolated from even significant moisture influxes at the surface. Although further research is necessary, important parallels exist between this Earthly desert analog and the possible existence and detection of subsurface life on Mars despite harsh abiotic conditions at the surface.

  13. On the Response of Halophilic Archaea to Space Conditions

    Science.gov (United States)

    Leuko, Stefan; Rettberg, Petra; Pontifex, Ashleigh L.; Burns, Brendan P.

    2014-01-01

    Microorganisms are ubiquitous and can be found in almost every habitat and ecological niche on Earth. They thrive and survive in a broad spectrum of environments and adapt to rapidly changing external conditions. It is of great interest to investigate how microbes adapt to different extreme environments and with modern human space travel, we added a new extreme environment: outer space. Within the last 50 years, technology has provided tools for transporting microbial life beyond Earth’s protective shield in order to study in situ responses to selected conditions of space. This review will focus on halophilic archaea, as, due to their ability to survive in extremes, they are often considered a model group of organisms to study responses to the harsh conditions associated with space. We discuss ground-based simulations, as well as space experiments, utilizing archaea, examining responses and/or resistance to the effects of microgravity and UV in particular. Several halophilic archaea (e.g., Halorubrum chaoviator) have been exposed to simulated and actual space conditions and their survival has been determined as well as the protective effects of halite shown. Finally, the intriguing potential of archaea to survive on other planets or embedded in a meteorite is postulated. PMID:25370029

  14. On the Response of Halophilic Archaea to Space Conditions

    Directory of Open Access Journals (Sweden)

    Stefan Leuko

    2014-02-01

    Full Text Available Microorganisms are ubiquitous and can be found in almost every habitat and ecological niche on Earth. They thrive and survive in a broad spectrum of environments and adapt to rapidly changing external conditions. It is of great interest to investigate how microbes adapt to different extreme environments and with modern human space travel, we added a new extreme environment: outer space. Within the last 50 years, technology has provided tools for transporting microbial life beyond Earth’s protective shield in order to study in situ responses to selected conditions of space. This review will focus on halophilic archaea, as, due to their ability to survive in extremes, they are often considered a model group of organisms to study responses to the harsh conditions associated with space. We discuss ground-based simulations, as well as space experiments, utilizing archaea, examining responses and/or resistance to the effects of microgravity and UV in particular. Several halophilic archaea (e.g., Halorubrum chaoviator have been exposed to simulated and actual space conditions and their survival has been determined as well as the protective effects of halite shown. Finally, the intriguing potential of archaea to survive on other planets or embedded in a meteorite is postulated.

  15. Exploration, antifungal and antiaflatoxigenic activity of halophilic bacteria communities from saline soils of Howze-Soltan playa in Iran.

    Science.gov (United States)

    Jafari, Samaneh; Aghaei, Seyed-Soheil; Afifi-Sabet, Hossein; Shams-Ghahfarokhi, Masoomeh; Jahanshiri, Zahra; Gholami-Shabani, Mohammadhassan; Shafiei-Darabi, Seyedahmad; Razzaghi-Abyaneh, Mehdi

    2018-01-01

    In the present study, halophilic bacteria communities were explored in saline soils of Howze-Soltan playa in Iran with special attention to their biological activity against an aflatoxigenic Aspergillus parasiticus NRRL 2999. Halophilic bacteria were isolated from a total of 20 saline soils using specific culture media and identified by 16S rRNA sequencing in neighbor-joining tree analysis. Antifungal and antiaflatoxigenic activities of the bacteria were screened by a nor-mutant A. parasiticus NRRL 2999 using visual agar plate assay and confirmed by high-performance liquid chromatography. Among a total of 177 halophilic bacteria belonging to 11 genera, 121 isolates (68.3%) inhibited A. parasiticus growth and/or aflatoxin production. The most potent inhibitory bacteria of the genera Bacillus, Paenibacillus and Staphylococcus were distributed in three main phylogenetic clusters as evidenced by 16S rRNA sequence analysis. A. parasiticus growth was inhibited by 0.7-92.7%, while AFB 1 and AFG 1 productions were suppressed by 15.1-98.9 and 57.0-99.6%, respectively. Taken together, halophilic bacteria identified in this study may be considered as potential sources of novel bioactive metabolites as well as promising candidates to develop new biocontrol agents for managing toxigenic fungi growth and subsequent aflatoxin contamination of food and feed in practice.

  16. Isolation and characterization of aerobic microorganisms with cellulolytic activity in the gut of endogeic earthworms.

    Science.gov (United States)

    Fujii, Katsuhiko; Ikeda, Kana; Yoshida, Seo

    2012-09-01

    The ability of earthworms to decompose lignocellulose involves the assistance of microorganisms in their digestive system. While many studies have revealed a diverse microbiota in the earthworm gut, including aerobic and anaerobic microorganisms, it remains unclear which of these species contribute to lignocellulose digestion. In this study, aerobic microorganisms with cellulolytic activity isolated from the gut of two endogeic earthworms, Amynthas heteropoda (Megascolecidae) and Eisenia fetida (Lumbricidae) were isolated by solid culture of gut homogenates using filter paper as a carbon source. A total of 48 strains, including four bacterial and four fungal genera, were isolated from two earthworm species. Characterization of these strains using enzyme assays showed that the most representative ones had exocellulase and xylanase activities, while some had weak laccase activity. These findings suggest that earthworms digest lignocellulose by exploiting microbial exocellulase and xylanase besides their own endocellulase. Phylogenetic analysis showed that among the cellulolytic isolates in both earthworm species Burkholderia and Chaetomium were the dominant bacterial and fungal members.

  17. Phenotypic characterization and 16S rDNA identification of culturable non-obligate halophilic bacterial communities from a hypersaline lake, La Sal del Rey, in extreme South Texas (USA).

    Science.gov (United States)

    Phillips, Kristen; Zaidan, Frederic; Elizondo, Omar R; Lowe, Kristine L

    2012-02-02

    La Sal del Rey ("the King's Salt") is one of several naturally-occurring salt lakes in Hidalgo County, Texas and is part of the Lower Rio Grande Valley National Wildlife Refuge. The research objective was to isolate and characterize halophilic microorganisms from La Sal del Rey. Water samples were collected from the lake and a small creek that feeds into the lake. Soil samples were collected from land adjacent to the water sample locations. Sample salinity was determined using a refractometer. Samples were diluted and cultured on a synthetic saline medium to grow halophilic bacteria. The density of halophiles was estimated by viable plate counts. A collection of isolates was selected, gram-stained, tested for catalase, and characterized using API 20E® test strips. Isolates were putatively identified by sequencing the 16S rDNA. Carbon source utilization by the microbial community from each sample site was examined using EcoPlate™ assays and the carbon utilization total activity of the community was determined. Results showed that salinity ranged from 4 parts per thousand (ppt) at the lake water source to 420 ppt in water samples taken just along the lake shore. The density of halophilic bacteria in water samples ranged from 1.2 × 102 - 5.2 × 103 colony forming units per ml (cfu ml-1) whereas the density in soil samples ranged from 4.0 × 105 - 2.5 × 106 colony forming units per gram (cfu g-1). In general, as salinity increased the density of the bacterial community decreased. Microbial communities from water and soil samples were able to utilize 12 - 31 carbon substrates. The greatest number of substrates utilized was by water-borne communities compared to soil-based communities, especially at lower salinities. The majority of bacteria isolated were gram-negative, catalase-positive, rods. Biochemical profiles constructed from API 20E® test strips showed that bacterial isolates from low-salinity water samples (4 ppt) showed the greatest phenotypic diversity

  18. Plutonium interaction with a bacterial strain isolated from the waste isolation pilot plant (WIPP) environment

    International Nuclear Information System (INIS)

    Strietelmeier, B.A.; Kraus, S.M.; Leonard, P.A.; Triay, I.R.

    1996-01-01

    This work was conducted as part of a series of experiments to determine the association and interaction of various actinides with bacteria isolated from the WIPP site. The majority of bacteria that exist at the site are expected to be halophiles, or extreme halophiles, due to the high concentration of salt minerals at the location. Experiments were conducted to determine the toxicity of plutonium-n-239, neptunium-237 and americium-243 to several species of these halophiles and the results were reported elsewhere. As an extension of these experiments, we report an investigation of the type of association that occurs between 239 Pu and the isolate WIPP-1A, isolated by staff at Brookhaven National Laboratory, when grown in a high-salt, defined medium. Using scanning electron microscopy (SEM) techniques, we demonstrate a surface association of the 239 Pu with the bacterial cells

  19. Metabolism, Physiology and Biotechnological Applications of Halobacteria

    OpenAIRE

    Oleg Mosin; Ignat Ignatov

    2015-01-01

    Halophiles (lat. “salt-loving”) is the taxonomic group of extreme aerobic obligate Gram-negative microorganisms that live in conditions of high salinity – in the seas, salt lakes, saline soils etc. These microorganisms are known to reddish patina on products, preserved with using large quantities of salt (NaCl). Halophiles were isolated for the first time at the beginning of the XX century from the marine flora estuary mud, but their systematic study was started only at the end of the second ...

  20. Investigation and Isolation of Cellulase-Producing microorganisms in the Red Sea

    KAUST Repository

    Fatani, Siham

    2016-01-01

    Cellulolytic microorganisms are considered to be key players in biorefinery, especially for the utilization of plant biomass. These organisms have been isolated from various environments. The Red Sea is one of the seas with high biodiversity and a

  1. Magnesium and manganese content of halophilic bacteria

    International Nuclear Information System (INIS)

    de Medicis, E.; Paquette, J.; Gauthier, J.J.; Shapcott, D.

    1986-01-01

    Magnesium and manganese contents were measured by atomic absorption spectrophotometry in bacteria of several halophilic levels, in Vibrio costicola, a moderately halophilic eubacterium growing in 1 M NaCl, Halobacterium volcanii, a halophilic archaebacterium growing in 2.5 NaCl, Halobacterium cutirubrum, an extremely halophilic archaebacterium growing in 4 M NaCl, and Escherichia coli, a nonhalophilic eubacterium growing in 0.17 M NaCl. Magnesium and manganese contents varied with the growth phase, being maximal at the early log phase. Magnesium and manganese molalities in cell water were shown to increase with the halophilic character of the logarithmically growing bacteria, from 30 mmol of Mg per kg of cell water and 0.37 mmol of Mn per kg of cell water for E. coli to 102 mmol of Mg per kg of cell water and 1.6 mmol of Mn per kg of cell water for H cutirubrum. The intracellular concentrations of manganese were determined independently by a radioactive tracer technique in V. costicola and H. volcanii. The values obtained by 54 Mn loading represented about 70% of the values obtained by atomic absorption. The increase of magnesium and manganese contents associated with the halophilic character of the bacteria suggests that manganese and magnesium play a role in haloadaptation

  2. Isolation of β-1,3-Glucanase-Producing Microorganisms from Poria cocos Cultivation Soil via Molecular Biology

    Directory of Open Access Journals (Sweden)

    Qiulan Wu

    2018-06-01

    Full Text Available β-1,3-Glucanase is considered as a useful enzymatic tool for β-1,3-glucan degradation to produce (1→3-linked β-glucan oligosaccharides with pharmacological activity properties. To validly isolate β-1,3-glucanase-producing microorganisms, the soil of Wolfiporia extensa, considered an environment rich in β-1,3-glucan-degrading microorganisms, was subjected to high throughput sequencing. The results demonstrated that the genera Streptomyces (1.90% and Arthrobacter (0.78% belonging to the order Actinomycetales (8.64% in the phylum Actinobacteria (18.64% were observed in soil for P. cocos cultivation (FTL1. Actinomycetes were considered as the candidates for isolation of glucan-degrading microorganisms. Out of 58 isolates, only 11 exhibited β-1,3-glucan-degrading activity. The isolate SYBCQL belonging to the genus Kitasatospora with β-1,3-glucan-degrading activity was found and reported for the first time and the isolate SYBC17 displayed the highest yield (1.02 U/mg among the isolates. To check the β-1,3-glucanase contribution to β-1,3-glucan-degrading activity, two genes, 17-W and 17-Q, encoding β-1,3-glucanase in SYBC17 and one gene QLK1 in SYBCQL were cloned and expressed for verification at the molecular level. Our findings collectively showed that the isolates able to secrete β-1,3-glucanase could be obtained with the assistance of high-throughput sequencing and genes expression analysis. These methods provided technical support for isolating β-1,3-glucanase-producing microorganisms.

  3. Taxonomic study and partial characterization of antimicrobial compounds from a moderately halophilic strain of the genus Actinoalloteichus

    Directory of Open Access Journals (Sweden)

    Farida Boudjelal

    2011-09-01

    Full Text Available A moderately halophilic actinomycete strain designated AH97 was isolated from a saline Saharan soil, and selected for its antimicrobial activities against bacteria and fungi. The AH97 strain was identified by morphological, chemotaxonomic and phylogenetic analyses to the genus Actinoalloteichus. Analysis of the 16S rDNA sequence of strain AH97 showed a similarity level ranging between 95.8% and 98.4% within Actinoalloteichus species, with A. hymeniacidonis the most closely related. The comparison of the physiological characteristics of AH97 with those of known species of Actinoalloteichus showed significant differences. Strain AH97 showed an antibacterial and antifungal activity against broad spectrum of microorganisms known to be human and plant pathogens. The bioactive compounds were extracted from the filtrate culture with n-butanol and purified using thin layer chromatography and high pressure liquid chromatography procedures. Two active products were isolated, one hydrophilic fraction (F1 and another hydrophobic (F2. Ultraviolet-visible, infrared, mass and ¹H and 13C nuclear magnetic resonance spectroscopy studies suggested that these molecules were the dioctyl phthalate (F2 and an aminoglycosidic compound (F1.

  4. Insights into the sequence parameters for halophilic adaptation.

    Science.gov (United States)

    Nath, Abhigyan

    2016-03-01

    The sequence parameters for halophilic adaptation are still not fully understood. To understand the molecular basis of protein hypersaline adaptation, a detailed analysis is carried out, and investigated the likely association of protein sequence attributes to halophilic adaptation. A two-stage strategy is implemented, where in the first stage a supervised machine learning classifier is build, giving an overall accuracy of 86 % on stratified tenfold cross validation and 90 % on blind testing set, which are better than the previously reported results. The second stage consists of statistical analysis of sequence features and possible extraction of halophilic molecular signatures. The results of this study showed that, halophilic proteins are characterized by lower average charge, lower K content, and lower S content. A statistically significant preference/avoidance list of sequence parameters is also reported giving insights into the molecular basis of halophilic adaptation. D, Q, E, H, P, T, V are significantly preferred while N, C, I, K, M, F, S are significantly avoided. Among amino acid physicochemical groups, small, polar, charged, acidic and hydrophilic groups are preferred over other groups. The halophilic proteins also showed a preference for higher average flexibility, higher average polarity and avoidance for higher average positive charge, average bulkiness and average hydrophobicity. Some interesting trends observed in dipeptide counts are also reported. Further a systematic statistical comparison is undertaken for gaining insights into the sequence feature distribution in different residue structural states. The current analysis may facilitate the understanding of the mechanism of halophilic adaptation clearer, which can be further used for rational design of halophilic proteins.

  5. Kocuria marina BS-15 a biosurfactant producing halophilic bacteria isolated from solar salt works in India

    Science.gov (United States)

    Sarafin, Yesurethinam; Donio, Mariathasan Birdilla Selva; Velmurugan, Subramanian; Michaelbabu, Mariavincent; Citarasu, Thavasimuthu

    2014-01-01

    Biosurfactant screening was made among the eight halophilic bacterial genera isolated from Kovalam solar salt works in Kanyakumari of India. After initial screening, Kocuria sp. (Km), Kurthia sp. (Ku) and Halococcus sp. (Hc) were found to have positive biosurfactant activity. Biosurfactant derived from Kocuria sp. emulsified more than 50% of the crude oil, coconut oil, sunflower oil, olive oil and kerosene when compared to the other strains. Further, Kocuria marina BS-15 derived biosurfactant was purified and characterized by TLC, FTIR and GC–MS analysis. The TLC analysis revealed that, the purified biosurfactants belong to the lipopeptide group. The IR spectrum results revealed that functional groups are R2C 000000000000 000000000000 000000000000 111111111111 000000000000 111111111111 000000000000 000000000000 000000000000 NN, alkenes and N–H. The GC–MS analysis confirmed the compound as Nonanoic acid and Cyclopropane with the retention time of 12.78 and 24.65, respectively. PMID:25473358

  6. Salt-bridge energetics in halophilic proteins.

    Science.gov (United States)

    Nayek, Arnab; Sen Gupta, Parth Sarthi; Banerjee, Shyamashree; Mondal, Buddhadev; Bandyopadhyay, Amal K

    2014-01-01

    Halophilic proteins have greater abundance of acidic over basic and very low bulky hydrophobic residues. Classical electrostatic stabilization was suggested as the key determinant for halophilic adaptation of protein. However, contribution of specific electrostatic interactions (i.e. salt-bridges) to overall stability of halophilic proteins is yet to be understood. To understand this, we use Adaptive-Poison-Boltzmann-Solver Methods along with our home-built automation to workout net as well as associated component energy terms such as desolvation energy, bridge energy and background energy for 275 salt-bridges from 20 extremely halophilic proteins. We then perform extensive statistical analysis on general and energetic attributes on these salt-bridges. On average, 8 salt-bridges per 150 residues protein were observed which is almost twice than earlier report. Overall contributions of salt-bridges are -3.0 kcal mol-1. Majority (78%) of salt-bridges in our dataset are stable and conserved in nature. Although, average contributions of component energy terms are equal, their individual details vary greatly from one another indicating their sensitivity to local micro-environment. Notably, 35% of salt-bridges in our database are buried and stable. Greater desolvation penalty of these buried salt-bridges are counteracted by stable network salt-bridges apart from favorable equal contributions of bridge and background terms. Recruitment of extensive network salt-bridges (46%) with a net contribution of -5.0 kcal mol-1 per salt-bridge, seems to be a halophilic design wherein favorable average contribution of background term (-10 kcal mol-1) exceeds than that of bridge term (-7 kcal mol-1). Interiors of proteins from halophiles are seen to possess relatively higher abundance of charge and polar side chains than that of mesophiles which seems to be satisfied by cooperative network salt-bridges. Overall, our theoretical analyses provide insight into halophilic signature in its

  7. Diversity of microorganisms isolated from the soil sample surround Chroogomphus rutilus in the Beijing region

    DEFF Research Database (Denmark)

    Wang, P; Liu, Y; Yin, Y

    2011-01-01

    to isolate and classify beneficial microorganisms that could affect its growth, which could be used in future research on artificial cultivation. In total, 342 isolates were isolated from soil samples collected around a C. rutilus colony in the Beijing region. Of these, 22 bacterial and 14 fungal isolates...

  8. Isolation of radioresistant microorganisms from a Co/sup 60/ irradiation plant

    International Nuclear Information System (INIS)

    Lezcano, Graciela

    1982-01-01

    The continuos exposition to low doses of gamma irradiation can produce changes in the microflora's radioresistance. In order to obtain information about these possible modifications, the water from the pool used as shielding of the source, as well as the air and the dust in the irradiation chamber of the semi-industrial irradiation plant existing at the Ezeiza Atomic Center were analyzed. The number of microorganisms was determined by filtration techniques and by dilutions. Radioresistance studies of the contaminating microflora were performed. The value of the D/sub 10/ dose was determined in the conditions of highest resistance. A pronounced decrease in the number of microorganisms was observed as a radiation effect in the samples of water and dust, but not in the air samples, this as a consequence of the extractors' action that continually renews the air and the flora in the chamber, thus preventing high-dose exposure. In the air samples no increase of the microorganisms' radioresistance was observed. In the pool water flora, the development of a great radioresistance was observed. A microorganism whose inactivation curve shows a shoulder of 3.2 Mrad was isolated. This high radioresistance could be the result of the continous exposure to low doses during six years. Contrarily, the microorganims of the irradiation chamber's dust did not increase their radioresistance wiht regard to the common contaminants. In the flora of the dust used as a target, two microorganims whose D/sub 10/ were in excess of 400 krad were found; these could be ocassional contaminants. The radioresistant microorganims were isolated and characterized according to Cowan's scheme, the water microorganisms being identified as belonging to the genus Corynebacterium and the earth ones to the genera Micrococcus and Corynebacterium. (author) [es

  9. The potential of subterranean microbes in facilitating actinide migration at the Grimsel test site and waste isolation pilot plant

    International Nuclear Information System (INIS)

    Gillow, J.B.; Dunn, M.; Francis, A.J.; Lucero, D.A.; Papenguth, H.W.

    2000-01-01

    Microorganisms may affect the long-term stability and mobility of radionuclides disposed of in deep geological formations. Of particular concern is the association of radionuclides with subterranean microbial cells and their subsequent transport as biocolloids. We characterized the total microbial populations in two groundwater samples: one from the Culebra dolomite member of the Rustler formation at the waste isolation pilot plant (WIPP), NM, and the other from the granitic formation at the Grimsel test site (GTS), Switzerland. Culebra groundwater (ionic strength 2.8 M, pH 7) contained 1.51 ± 1.08 x 10 5 cells ml -1 , with a mean cell length of 0.75 ± 0.04 μm and width of 0.58 ± 0.02 μm. In contrast, low ionic-strength GTS groundwater (0.001 M, pH 10) contained 3.97 ± 0.37 x 10 3 cells ml -1 , with a mean cell length of 1.50 ± 0.14 μm and width of 0.37 ± 0.01 μm. Adding appropriate electron donors and acceptors to the groundwaters facilitated the growth of aerobic, denitrifying, fermentative, and acetogenic microorganisms. Uranium biosorption was studied in two isolates from these groundwaters, as well as several pure cultures from saline and non-saline environments. Halophilic and non-halophilic bacteria exhibited differences in the amount of U associated with the cells. Plutonium uptake by Acetobacterium sp. isolated from GTS varied from 30-145 pg of Pu mg -1 dry weight of cells. (orig.)

  10. Halophilic archaea cultivated from surface sterilized middle-late eocene rock salt are polyploid.

    Directory of Open Access Journals (Sweden)

    Salla T Jaakkola

    Full Text Available Live bacteria and archaea have been isolated from several rock salt deposits of up to hundreds of millions of years of age from all around the world. A key factor affecting their longevity is the ability to keep their genomic DNA intact, for which efficient repair mechanisms are needed. Polyploid microbes are known to have an increased resistance towards mutations and DNA damage, and it has been suggested that microbes from deeply buried rock salt would carry several copies of their genomes. Here, cultivable halophilic microbes were isolated from a surface sterilized middle-late Eocene (38-41 million years ago rock salt sample, drilled from the depth of 800 m at Yunying salt mine, China. Eight unique isolates were obtained, which represented two haloarchaeal genera, Halobacterium and Halolamina. We used real-time PCR to show that our isolates are polyploid, with genome copy numbers of 11-14 genomes per cell in exponential growth phase. The ploidy level was slightly downregulated in stationary growth phase, but the cells still had an average genome copy number of 6-8. The polyploidy of halophilic archaea living in ancient rock salt might be a factor explaining how these organisms are able to overcome the challenge of prolonged survival during their entombment.

  11. In vitro degradation of linamarin by microorganisms isolated from cassava wastewater treatment lagoons

    Directory of Open Access Journals (Sweden)

    S. P Vasconcellos

    2009-12-01

    Full Text Available This study aimed at isolating and characterizing of microorganisms able to use linamarin as sole carbon source. Thirty one microbial strains were isolated from manipueira, a liquid effluent of cassava processing factories. Among these strains, Bacillus licheniformis (isolate 2_2 and Rhodotorulla glutinis (isolate L1 were able to degrade 71% and 95% of added linamarin, respectively, within 7 days, showing high biodegradation activity and great potential for detoxification of cassava processing wastewaters.

  12. Purification and characterization of an extracellular halophilic and organic solvent-tolerant amylopullulanase from a haloarchaeon, Halorubrum sp. strain Ha25.

    Directory of Open Access Journals (Sweden)

    Mostafa Fazeli

    2013-01-01

    Full Text Available Introduction: Halophiles, especially haloarchaea are one of the most important groups of extremophiles. Halophilic hydrolases have been studied worldwide and have been considered for biotechnology and industrial technologies. This study is the first report in amylopullulanase production in halophilic microorganisms.Materials and methods: A halophilic archaeon, Halorubrum sp. strain Ha25, produced extracellular halophilic organic solvent-tolerant amylopullulanase. The enzyme was purified using ethanol precipitation and anion exchange chromatography method. Molecular mass of purified enzyme was determined by SDS–PAGE method. After purification, the enzyme was characterized. To study the effects of organic solvents in the stability of the enzyme, the enzyme solution was incubated in the presence of various organic compounds and then, residual enzyme activity was measured. Mode of action of the enzyme was determined by thin-layer chromatography.Results: Molecular weight of the purified enzyme was estimated to be 140 kDa by SDS–PAGE method. Optimum temperature for amylolitic and pullulytic activities was 50 °C. Optimum pH for amylolitic activity was 7.0 and for pullulytic activity was 7.5. This enzyme was active over a wide range of concentrations (0-4.5 M of NaCl. The effect of organic solvents on the amylolitic and pullulytic activities showed that this enzyme was more stable in the presence of non-polar organic solvents than polar solvents. The enzyme solely hydrolyzed pullulan and soluble starch to glucose.Discussion and conclusion: Halorubrum sp. strain Ha25 produces thermophilic and extremely halophilic amylopullulanase. The catalytic function under multi extreme condition of high temperature, high salinity, and low water activity might possess biotechnological and commercial values such as treatment waste solutions with starch residues, high salt content and solvents.

  13. Distinct Osmoadaptation Strategies in the Strict Halophilic and Halotolerant Bacteria Isolated from Lunsu Salt Water Body of North West Himalayas.

    Science.gov (United States)

    Vaidya, Shivani; Dev, Kamal; Sourirajan, Anuradha

    2018-07-01

    Two strict halophilic bacterial strains, Halobacillus trueperi SS1, and Halobacillus trueperi SS3, and three halotolerant bacterial strains, Shewanella algae SS2, Halomonas venusta SS5, and Marinomonas sp. SS8 of Lunsu salt water body, Himachal Pradesh, India, were selected to study the mechanism of salt tolerance and the role of osmolytes therein. A combination of flame photometry, chromatographic and colorimetric assays was used to study the mechanism of salt tolerance in the selected strict halophilic and halotolerant bacterial strains. The strict halophiles and, one of the halotolerants, Marinomonas sp. SS8 were found to utilize both "salt-in strategy" and "accumulation of compatible solutes strategy" for osmoregulation in hypersaline conditions. On the contrary, the remaining two halotolerants used "accumulation of compatible solutes strategy" under saline stress and not the "salt-in strategy". The present study suggests towards distinct mechanisms of salt tolerance in the two classes, wherein strict halophiles accumulate compatible solutes as well as adopt salt-in strategy, while the halotolerant bacteria accumulate a range of compatible solutes, except Marinomonas sp. SS8, which utilizes both the strategies to combat salt stress.

  14. Approach toward enhancement of halophilic protease production by Halobacterium sp. strain LBU50301 using statistical design response surface methodology.

    Science.gov (United States)

    Chuprom, Julalak; Bovornreungroj, Preeyanuch; Ahmad, Mehraj; Kantachote, Duangporn; Dueramae, Sawitree

    2016-06-01

    A new potent halophilic protease producer, Halobacterium sp. strain LBU50301 was isolated from salt-fermented fish samples ( budu ) and identified by phenotypic analysis, and 16S rDNA gene sequencing. Thereafter, sequential statistical strategy was used to optimize halophilic protease production from Halobacterium sp. strain LBU50301 by shake-flask fermentation. The classical one-factor-at-a-time (OFAT) approach determined gelatin was the best nitrogen source. Based on Plackett - Burman (PB) experimental design; gelatin, MgSO 4 ·7H 2 O, NaCl and pH significantly influenced the halophilic protease production. Central composite design (CCD) determined the optimum level of medium components. Subsequently, an 8.78-fold increase in corresponding halophilic protease yield (156.22 U/mL) was obtained, compared with that produced in the original medium (17.80 U/mL). Validation experiments proved the adequacy and accuracy of model, and the results showed the predicted value agreed well with the experimental values. An overall 13-fold increase in halophilic protease yield was achieved using a 3 L laboratory fermenter and optimized medium (231.33 U/mL).

  15. Approach toward enhancement of halophilic protease production by Halobacterium sp. strain LBU50301 using statistical design response surface methodology

    Directory of Open Access Journals (Sweden)

    Julalak Chuprom

    2016-06-01

    Full Text Available A new potent halophilic protease producer, Halobacterium sp. strain LBU50301 was isolated from salt-fermented fish samples (budu and identified by phenotypic analysis, and 16S rDNA gene sequencing. Thereafter, sequential statistical strategy was used to optimize halophilic protease production from Halobacterium sp. strain LBU50301 by shake-flask fermentation. The classical one-factor-at-a-time (OFAT approach determined gelatin was the best nitrogen source. Based on Plackett–Burman (PB experimental design; gelatin, MgSO4·7H2O, NaCl and pH significantly influenced the halophilic protease production. Central composite design (CCD determined the optimum level of medium components. Subsequently, an 8.78-fold increase in corresponding halophilic protease yield (156.22 U/mL was obtained, compared with that produced in the original medium (17.80 U/mL. Validation experiments proved the adequacy and accuracy of model, and the results showed the predicted value agreed well with the experimental values. An overall 13-fold increase in halophilic protease yield was achieved using a 3 L laboratory fermenter and optimized medium (231.33 U/mL.

  16. Isolation of microorganisms involved in reduction of crystalline iron(III) oxides in natural environments.

    Science.gov (United States)

    Hori, Tomoyuki; Aoyagi, Tomo; Itoh, Hideomi; Narihiro, Takashi; Oikawa, Azusa; Suzuki, Kiyofumi; Ogata, Atsushi; Friedrich, Michael W; Conrad, Ralf; Kamagata, Yoichi

    2015-01-01

    Reduction of crystalline Fe(III) oxides is one of the most important electron sinks for organic compound oxidation in natural environments. Yet the limited number of isolates makes it difficult to understand the physiology and ecological impact of the microorganisms involved. Here, two-stage cultivation was implemented to selectively enrich and isolate crystalline iron(III) oxide reducing microorganisms in soils and sediments. Firstly, iron reducers were enriched and other untargeted eutrophs were depleted by 2-years successive culture on a crystalline ferric iron oxide (i.e., goethite, lepidocrocite, hematite, or magnetite) as electron acceptor. Fifty-eight out of 136 incubation conditions allowed the continued existence of microorganisms as confirmed by PCR amplification. High-throughput Illumina sequencing and clone library analysis based on 16S rRNA genes revealed that the enrichment cultures on each of the ferric iron oxides contained bacteria belonging to the Deltaproteobacteria (mainly Geobacteraceae), followed by Firmicutes and Chloroflexi, which also comprised most of the operational taxonomic units (OTUs) identified. Venn diagrams indicated that the core OTUs enriched with all of the iron oxides were dominant in the Geobacteraceae while each type of iron oxides supplemented selectively enriched specific OTUs in the other phylogenetic groups. Secondly, 38 enrichment cultures including novel microorganisms were transferred to soluble-iron(III) containing media in order to stimulate the proliferation of the enriched iron reducers. Through extinction dilution-culture and single colony isolation, six strains within the Deltaproteobacteria were finally obtained; five strains belonged to the genus Geobacter and one strain to Pelobacter. The 16S rRNA genes of these isolates were 94.8-98.1% identical in sequence to cultured relatives. All the isolates were able to grow on acetate and ferric iron but their physiological characteristics differed considerably in

  17. Isolation and characterization from solar salterns of North Algeria of a haloarchaeon producing a new halocin.

    Science.gov (United States)

    Mazguene, Souhila; Rossi, Mosè; Gogliettino, Marta; Palmieri, Gianna; Cocca, Ennio; Mirino, Sara; Imadalou-Idres, Nacera; Benallaoua, Said

    2018-03-01

    Halophilic archaea, thriving in hypersaline environments, synthesize antimicrobial substances with an unknown role, called halocins. It has been suggested that halocin production gives transient competitive advantages to the producer strains and represents one of the environmental factors influencing the microbial community composition. Herein, we report on the antibacterial activity of a new haloarchaeon selected from solar salterns of the northern coast of Algeria. A total of 81 halophilic strains, isolated from the microbial consortia, were screened for the production of antimicrobial compounds by interspecies competition test and against a collection of commercial haloarchaea. On the basis of the partial 16S rRNA sequencing, the most efficient halocin producer was recognized as belonging to Haloferax (Hfx) sp., while the best indicator microorganism, showing high sensitivity toward halocin, was related to Haloarcula genus. The main morphological, physiological and biochemical properties of Hfx were investigated and a partial purification of the produced halocin was allowed to identify it as a surface membrane protein with a molecular mass between 30 and 40 kDa. Therefore, in this study, we isolated a new strain belonging to Haloferax genus and producing a promising antimicrobial compound useful for applications in health and food industries.

  18. Systematic and biotechnological aspects of halophilic and halotolerant actinomycetes.

    Science.gov (United States)

    Hamedi, Javad; Mohammadipanah, Fatemeh; Ventosa, Antonio

    2013-01-01

    More than 70 species of halotolerant and halophilic actinomycetes belonging to at least 24 genera have been validly described. Halophilic actinomycetes are a less explored source of actinomycetes for discovery of novel bioactive secondary metabolites. Degradation of aliphatic and aromatic organic compounds, detoxification of pollutants, production of new enzymes and other metabolites such as antibiotics, compatible solutes and polymers are other potential industrial applications of halophilic and halotolerant actinomycetes. Especially new bioactive secondary metabolites that are derived from only a small fraction of the investigated halophilic actinomycetes, mainly from marine habitats, have revealed the huge capacity of this physiological group in production of new bioactive chemical entities. Combined high metabolic capacities of actinomycetes and unique features related to extremophilic nature of the halophilic actinomycetes have conferred on them an influential role for future biotechnological applications.

  19. Stability of halophilic proteins: from dipeptide attributes to discrimination classifier.

    Science.gov (United States)

    Zhang, Guangya; Huihua, Ge; Yi, Lin

    2013-02-01

    To investigate the molecular features responsible for protein halophilicity is of great significance for understanding the structure basis of protein halo-stability and would help to develop a practical strategy for designing halophilic proteins. In this work, we have systematically analyzed the dipeptide composition of the halophilic and non-halophilic protein sequences. We observed the halophilic proteins contained more DA, RA, AD, RR, AP, DD, PD, EA, VG and DV at the expense of LK, IL, II, IA, KK, IS, KA, GK, RK and AI. We identified some macromolecular signatures of halo-adaptation, and thought the dipeptide composition might contain more information than amino acid composition. Based on the dipeptide composition, we have developed a machine learning method for classifying halophilic and non-halophilic proteins for the first time. The accuracy of our method for the training dataset was 100.0%, and for the 10-fold cross-validation was 93.1%. We also discussed the influence of some specific dipeptides on prediction accuracy. Copyright © 2012 Elsevier B.V. All rights reserved.

  20. Characterization of Halophilic Bacterial Communities in Turda Salt Mine (Romania)

    Science.gov (United States)

    Carpa, Rahela; Keul, Anca; Muntean, Vasile; Dobrotă, Cristina

    2014-09-01

    Halophilic organisms are having adaptations to extreme salinity, the majority of them being Archaean, which have the ability to grow at extremely high salt concentrations, (from 3 % to 35 %). Level of salinity causes natural fluctuations in the halophilic populations that inhabit this particular habitat, raising problems in maintaining homeostasis of the osmotic pressure. Samples such as salt and water taken from Turda Salt Mine were analyzed in order to identify the eco-physiological bacterial groups. Considering the number of bacteria of each eco-physiological group, the bacterial indicators of salt quality (BISQ) were calculated and studied for each sample. The phosphatase, catalase and dehydrogenases enzymatic activities were quantitatively determined and the enzymatic indicators of salt quality (EISQ) were calculated. Bacterial isolates were analyzed using 16S rRNA gene sequence analysis. Universal bacterial primers, targeting the consensus region of the bacterial 16S rRNA gene were used. Analysis of a large fragment, of 1499 bp was performed to improve discrimination at the species level.

  1. Halorubrum depositum sp. nov., a Novel Halophilic Archaeon Isolated from a Salt Deposit.

    Science.gov (United States)

    Chen, Shaoxing; Sun, Siqi; Xu, Yao; Lv, Jinting; Chen, Linan; Liu, Liu

    2018-06-01

    A non-motile, pleomorphic rod-shaped or oval, red-pigmented (nearly scarlet), extremely halophilic archaeon, strain Y78 T , was isolated from a salt deposit of Yunnan salt mine, China. Analysis of the 16S rRNA gene sequence showed that it was phylogenetically related to species of the genus Halorubrum, with a close relationship to Halorubrum rutilum YJ-18-S1 T (98.6%), Halorubrum yunnanense Q85 T (98.3%), and Halorubrum lipolyticum 9-3 T (98.1%). The temperature, NaCl, and pH ranges for growth were 25-50 °C, 12-30% (w/v), and 6.5-9.0, respectively. Mg 2+ was required for growth. The polar lipids of strain Y78 T were phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate, and a sulfated diglycosyl diether. The DNA G+C content was 66.6 mol%. DNA-DNA hybridization values between strain Y78 T and two closely related species of the genus Halorubrum were far below 70%. Based on the data presented in this study, strain Y78 T represents a novel species for which the name Halorubrum depositum sp. nov. is proposed; the type strain is Y78 T (= CGMCC 1.15456 T  = JCM 31272 T ).

  2. Production and properties of an exopolysaccharide synthesized by the extreme halophilic archaeon Haloterrigena turkmenica.

    Science.gov (United States)

    Squillaci, Giuseppe; Finamore, Rosario; Diana, Paola; Restaino, Odile Francesca; Schiraldi, Chiara; Arbucci, Salvatore; Ionata, Elena; La Cara, Francesco; Morana, Alessandra

    2016-01-01

    We have isolated a novel exopolysaccharide (EPS) produced by the extreme halophilic archaeon Haloterrigena turkmenica. Some features, remarkable from an industrial point of view, such as emulsifying and antioxidant properties, were investigated. H. turkmenica excreted 20.68 mg of EPS per 100 ml of culture medium when grown in usual medium supplemented with glucose. The microorganism excreted the biopolymer mainly in the middle exponential growth phase and reached the maximal production in the stationary phase. Analyses by anion exchange chromatography and SEC-TDA Viscotek indicated that the EPS was composed of two main fractions of 801.7 and 206.0 kDa. It was a sulfated heteropolysaccharide containing glucose, galactose, glucosamine, galactosamine, and glucuronic acid. Studies performed utilizing the mixture of EPS anionic fractions showed that the biopolymer had emulsifying activity towards vegetable oils comparable or superior to that exhibited by the controls, moderate antioxidant power when tested with 2,2'-diphenyl-1-picrylhydrazyl (DPPH(·)), and moisture-retention ability higher than hyaluronic acid (HA). The EPS from H. turkmenica is the first exopolysaccharide produced by an archaea to be characterized in terms of properties that can have potential biotechnological applications.

  3. Low Water Activity Induces the Production of Bioactive Metabolites in Halophilic and Halotolerant Fungi

    Directory of Open Access Journals (Sweden)

    Nina Gunde-Cimerman

    2010-12-01

    Full Text Available The aim of the present study was to investigate indigenous fungal communities isolated from extreme environments (hypersaline waters of solar salterns and subglacial ice, for the production of metabolic compounds with selected biological activities: hemolysis, antibacterial, and acetylcholinesterase inhibition. In their natural habitats, the selected fungi are exposed to environmental extremes, and therefore the production of bioactive metabolites was tested under both standard growth conditions for mesophilic microorganisms, and at high NaCl and sugar concentrations and low growth temperatures. The results indicate that selected halotolerant and halophilic species synthesize specific bioactive metabolites under conditions that represent stress for non-adapted species. Furthermore, adaptation at the level of the chemical nature of the solute lowering the water activity of the medium was observed. Increased salt concentrations resulted in higher hemolytic activity, particularly within species dominating the salterns. The appearance of antibacterial potential under stress conditions was seen in the similar pattern of fungal species as for hemolysis. The active extracts exclusively affected the growth of the Gram-positive bacterium tested, Bacillus subtilis. None of the extracts tested showed inhibition of acetylcholinesterase activity.

  4. Isolation of phyllosilicate-iron redox cycling microorganisms from an illite-smectite rich hydromorphic soil.

    Science.gov (United States)

    Shelobolina, Evgenya; Konishi, Hiromi; Xu, Huifang; Benzine, Jason; Xiong, Mai Yia; Wu, Tao; Blöthe, Marco; Roden, Eric

    2012-01-01

    The biogeochemistry of phyllosilicate-Fe redox cycling was studied in a Phalaris arundinacea (reed canary grass) dominated redoximorphic soil from Shovelers Sink, a small glacial depression near Madison, WI. The clay size fraction of Shovelers Sink soil accounts for 16% of the dry weight of the soil, yet contributes 74% of total Fe. The dominant mineral in the clay size fraction is mixed layer illite-smectite, and in contrast to many other soils and sediments, Fe(III) oxides are present in low abundance. We examined the Fe biogeochemistry of Shovelers Sink soils, estimated the abundance of Fe redox cycling microorganisms, and isolated in pure culture representative phyllosilicate-Fe oxidizing and reducing organisms. The abundance of phyllosilicate-Fe reducing and oxidizing organisms was low compared to culturable aerobic heterotrophs. Both direct isolation and dilution-to-extinction approaches using structural Fe(II) in Bancroft biotite as a Fe(II) source, and O(2) as the electron acceptor, resulted in recovery of common rhizosphere organisms including Bradyrhizobium spp. and strains of Cupriavidus necator and Ralstonia solanacearum. In addition to oxidizing biotite and soluble Fe(II) with O(2), each of these isolates was able to oxidize Fe(II) in reduced NAu-2 smectite with [Formula: see text] as the electron acceptor. Oxidized NAu-2 smectite or amorphous Fe(III) oxide served as electron acceptors for enrichment and isolation of Fe(III)-reducing microorganisms, resulting in recovery of a strain related to Geobacter toluenoxydans. The ability of the recovered microorganisms to cycle phyllosilicate-Fe was verified in an experiment with native Shovelers Sink clay. This study confirms that Fe in the native Shovelers Sink clay is readily available for microbial redox transformation and can be cycled by the Fe(III)-reducing and Fe(II)-oxidizing microorganisms recovered from the soil.

  5. Isolation of Phyllosilicate–Iron Redox Cycling Microorganisms from an Illite–Smectite Rich Hydromorphic Soil

    Science.gov (United States)

    Shelobolina, Evgenya; Konishi, Hiromi; Xu, Huifang; Benzine, Jason; Xiong, Mai Yia; Wu, Tao; Blöthe, Marco; Roden, Eric

    2012-01-01

    The biogeochemistry of phyllosilicate–Fe redox cycling was studied in a Phalaris arundinacea (reed canary grass) dominated redoximorphic soil from Shovelers Sink, a small glacial depression near Madison, WI. The clay size fraction of Shovelers Sink soil accounts for 16% of the dry weight of the soil, yet contributes 74% of total Fe. The dominant mineral in the clay size fraction is mixed layer illite–smectite, and in contrast to many other soils and sediments, Fe(III) oxides are present in low abundance. We examined the Fe biogeochemistry of Shovelers Sink soils, estimated the abundance of Fe redox cycling microorganisms, and isolated in pure culture representative phyllosilicate–Fe oxidizing and reducing organisms. The abundance of phyllosilicate–Fe reducing and oxidizing organisms was low compared to culturable aerobic heterotrophs. Both direct isolation and dilution-to-extinction approaches using structural Fe(II) in Bancroft biotite as a Fe(II) source, and O2 as the electron acceptor, resulted in recovery of common rhizosphere organisms including Bradyrhizobium spp. and strains of Cupriavidus necator and Ralstonia solanacearum. In addition to oxidizing biotite and soluble Fe(II) with O2, each of these isolates was able to oxidize Fe(II) in reduced NAu-2 smectite with NO3- as the electron acceptor. Oxidized NAu-2 smectite or amorphous Fe(III) oxide served as electron acceptors for enrichment and isolation of Fe(III)-reducing microorganisms, resulting in recovery of a strain related to Geobacter toluenoxydans. The ability of the recovered microorganisms to cycle phyllosilicate–Fe was verified in an experiment with native Shovelers Sink clay. This study confirms that Fe in the native Shovelers Sink clay is readily available for microbial redox transformation and can be cycled by the Fe(III)-reducing and Fe(II)-oxidizing microorganisms recovered from the soil. PMID:22493596

  6. Radiosensitivity of microorganisms isolated from radioactive waste repository

    International Nuclear Information System (INIS)

    Gazso, Lajos

    2001-01-01

    Bacteria are much more diverse in comparison with plants and animals. Among the huge diversity of bacteria there are microorganisms capable to grow at or adapt to extreme conditions. Some bacteria grow at temperature above 100 deg. C, other thrive in high salinity such as 20-30% NaCl, still others can live at pH lower than 2 or pH higher than 10 or exhibit high radioresistance. Due to accelerated disarmament and nuclear energy activities, large quantities of radioactive waste and nuclear fuel are being placed in storage areas. The awareness the microbial activity could potentially effect the performance of a system for geological disposal of radioactive waste gained acceptance in the early to middle 1980s, and as a result many countries considering developing programmes to study and quantify microbial effects in terms of their own particular disposal concept. A new research programme was launched in 1995, sponsored by the NATO Scientific Affairs Division, for studying microbiologically influenced corrosion (MIC) in radioactive waste repositories and spent fuel storage area. Our programme concerns several major items that may have an influence on the mobility of radionuclides in direct and indirect ways thereby being important for the safety analysis. They are uptake and transport of radionuclides by microorganisms, diversity and distribution of subterranean bacteria in typical repository environments, environmental limitation and bacterial activity, effect of bacterial activity on the mobility of radionuclides, microbial gas production and consumption, bacterial recombination of hydrogen and oxygen from radiolysis, and microbially induced corrosion of waste canister. The Permian Boda Claystone Formation in the Mecsek Hill area is being considered for high level waste disposal. Groundwater, technical water, rock and surface samples were collected aseptically from different depths. The quantitative and qualitative analysis of aerobic and anaerobe isolates were

  7. Extracellular proteases of Halobacillus blutaparonensis strain M9, a new moderately halophilic bacterium.

    Science.gov (United States)

    Santos, Anderson F; Valle, Roberta S; Pacheco, Clarissa A; Alvarez, Vanessa M; Seldin, Lucy; Santos, André L S

    2013-12-01

    Halophilic microorganisms are source of potential hydrolytic enzymes to be used in industrial and/or biotechnological processes. In the present study, we have investigated the ability of the moderately halophilic bacterium Halobacillus blutaparonensis (strain M9), a novel species described by our group, to release proteolytic enzymes. This bacterial strain abundantly proliferated in Luria-Bertani broth supplemented with 2.5% NaCl as well as secreted proteases to the extracellular environment. The production of proteases occurred in bacterial cells grown under different concentration of salt, ranging from 0.5% to 10% NaCl, in a similar way. The proteases secreted by H. blutaparonensis presented the following properties: (i) molecular masses ranging from 30 to 80 kDa, (ii) better hydrolytic activities under neutral-alkaline pH range, (iii) expression modulated according to the culture age, (iv) susceptibility to phenylmethylsulphonyl fluoride, classifying them as serine-type proteases, (v) specific cleavage over the chymotrypsin substrate, and (vi) enzymatic stability in the presence of salt (up to 20% NaCl) and organic solvents (e.g., ether, isooctane and cyclohexane). The proteases described herein are promising for industrial practices due to its haloalkaline properties.

  8. Diversity of biosurfactant producing microorganisms isolated from soils contaminated with diesel oil.

    Science.gov (United States)

    Menezes Bento, Fátima; de Oliveira Camargo, Flavio A; Okeke, Benedict C; Frankenberger, William T

    2005-01-01

    Biosurfactant production is a desirable property of hydrocarbon-degrading microorganisms (HDM). We characterized biosurfactant producing microbial populations from a Long Beach soil, California (USA) and a Hong Kong soil (China), contaminated with diesel oil. A total of 33 hydrocarbon-utilizing microorganisms were isolated from the soils. Twelve isolates and three defined consortia were tested for biosurfactant production and emulsification activity. The highest reduction of surface tension was achieved with a consortium of L1, L2 and L3 isolates from a Long Beach soil (41.4mN m(-1)). Isolate L1 (Acinetobacter junii) displayed the highest reduction of surface tension (46.5 mN m(-1)). The emulsifying capacity evaluated by the E24 emulsification index was highest in the culture of isolate L5 (74%). No substantial emulsification was achieved with the cell-free extracts, indicating that the emulsifying activity was not extracellular. Based on surface tension and the E24 index results, isolates F1, F2, F3, F4, L1, L2, L3 and L4 were identified by 16S rRNA gene sequencing as Bacillus cereus, Bacillus sphaericus, B. fusiformis, Acinetobacter junii, a non-cultured bacterium, Pseudomonas sp. and B. pumilus, respectively. Cluster analyses of 16S rRNA gene sequences of the bacterial isolates revealed 70% similarity amongst hydrocarbon-degrading bacterial community present in both soils. Five isolates (isolates F1, F2, F3, F4 and L4) belong to the Firmicutes order, two isolates (L1 and L3) belong to the Proteobacteria order and one isolate (L2) is an Actinomyces sp. Simpson's index (1 - D) and the Shannon-Weaver index (H) revealed more diversity of HDM in the Hong Kong soil, while evenness (E) and the equitability (J) data indicated that there was not a dominant population. Bacterial isolates displaying substantial potential for production of biosurfactants can be applied in the bioremediation of soils contaminated with petroleum hydrocarbons.

  9. Isolation of microorganisms with chinitase, protease and keratinase activities from petroleum contaminated soils

    International Nuclear Information System (INIS)

    Cervantes-Gonzalez, E.; Rojas-Avelizapa, L.; Cruz-Camarillo, R.; Rojas-Avelizapa, N.G.

    2005-01-01

    The most important part in one process of bio-remediation are the microorganisms with the capacities to degrade target compounds, this research is based to find microorganisms hydrocarbon-clastic with enzyme activities to degrade chicken feather (keratinolytic activity) which is also a contaminant and has been used such as sorbent of petroleum and can be composted after the oil spill cleanup is complete, the isolation was also to degrade shrimp waste (chitinolitic and proteolitic activity) which is waste material that can be used in compost or such as sorbent of petroleum too. We isolated mesofilic aerobic microorganisms from mexican soils located in Tabasco, Mexico. We achieved to isolate 105 bacteria from 10 soils, 90% was Bacillus Gram (-) which are common in soils and all were hydrocarbon-clastic, only 7 different bacteria had protease and chitinase activity and 12 bacteria had keratinase activity. So we found three fungi and one actinomycete with capacity to degrade hydrocarbons and presence of chitinase activity. The results of growth and enzyme activities in liquid culture showed that the protease activity was produced between 18 and 48 h in almost all bacteria, the chitinase activity started at 12 h but was slight , only 0.5 U/ml, and the keratinase activity was produced after 6 h of incubation and there were correlation between logarithmic phase of growth and enzymes production. With this study we showed the existence of some enzyme activities from microorganisms that live in hostile habitats. This, can be useful in bio-treatment soils by the possible use of this type of residues that can be bio-degraded at the same time that the hydrocarbons increasing the speed or the quality of cleanup in soils. (authors)

  10. Screening and Isolation of Associated Bioactive Microorganisms from Fasciospongia cavernosa from of Visakhapatnam Coast, Bay of Bengal

    Directory of Open Access Journals (Sweden)

    P. Shamsher Kumar

    2012-01-01

    Full Text Available Nature, especially the marine environment, provides the most effective drugs used in human therapy. Among the metazoans, the marine sponges produce the most potent and highly selective bioactive secondary metabolites. These animals (or their associated symbiotic microorganisms synthesize secondary metabolites whose activity and selectivity has developed during their long evolutionary history. During the course of exploitation of these resources two marine sponges, Fasciospongia cavernosa doc var.brown (dark brown Fasciospongia cavernosa doc var.yellow (yellow collected from the visakhapatnam coast of Bay of Bengal were investigated in order to assess the potential of these microorganisms for the production of antimicrobial compounds. The aqueous and organic extracts of both the sponges showed broad spectrum antibiotic activity. In this study a total of 178 microorganisms were isolated from different parts of two sponges and most of them from middle part of the sponge. The isolates were investigated in order to assess the potential of these microorganisms for the production of antimicrobial compounds. Testing for antimicrobial activities were performed against Gram-positive (Staphylococcus aureus, Bacillus subtilis, Bacillus cereus Gram-negative bacteria (Pseudomonas aeruginosa, Escherichia coli, Proteus vulgaris, fungi (Candida albicans, Aspergillus niger and 10 pathogenic organisms. Resulting mean diameter of inhibition zones revealed isolates B4 & B6 were the most potent of all the isolates. The present study has revealed the presence of high numbers of diverse culturable microorganisms associated with the marine sponges from Visakhapatnam Coast of Bay of Bengal as well as their potential to produce bioactive metabolites.

  11. Anti-methicillin Resistant Staphylococcus aureus Compound Isolation from Halophilic Bacillus amyloliquefaciens MHB1 and Determination of Its Mode of Action Using Electron Microscope and Flow Cytometry Analysis.

    Science.gov (United States)

    Jeyanthi, Venkadapathi; Velusamy, Palaniyandi

    2016-06-01

    The aim of this study was to purify, characterize and evaluate the antibacterial activity of bioactive compound against methicillin-resistant Staphylococcus aureus (MRSA). The anti-MRSA compound was produced by a halophilic bacterial strain designated as MHB1. The MHB1 strain exhibited 99 % similarity to Bacillus amyloliquefaciens based on 16S rRNA gene analysis. The culture conditions of Bacillus amyloliquefaciens MHB1 were optimized using nutritional and environmental parameters for enhanced anti-MRSA compound production. The pure bioactive compound was isolated using silica gel column chromatography and Semi-preparative High-performance liquid chromatography (Semi-preparative HPLC). The Thin layer chromatography, Fourier transform infrared spectroscopy and proton NMR ((1)H NMR) analysis indicated the phenolic nature of the compound. The molecular mass of the purified compound was 507 Da as revealed by Liquid chromatography-mass spectrometry (LC-MS) analysis. The compound inhibited the growth of MRSA with minimum inhibitory concentration (MIC) of 62.5 µg mL(-1). MRSA bacteria exposed to 4× MIC of the compound and the cell viability was determined using flow cytometric analysis. Scanning electron microscope and Transmission electron microscope analysis was used to determine the ultrastructural changes in bacteria. This is the first report on isolation of anti-MRSA compound from halophilic B. amyloliquefaciens MHB1 and could act as a promising biocontrol agent.

  12. Marine microorganisms. Umi no biseibutsu

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, U. (Hiroshima University, Hiroshima (Japan). Faculty of Applied Biological Science)

    1992-11-10

    This paper explains properties, interactions, and activities of marine microorganisms. Marine bacteria include bacteria of vibrio family of arteromonas genus, luminous bacteria, and aerobic photosynthetic bacteria. Majority of marine bacteria is halophilic, and many proliferate at 5[degree]C or lower. Some of them can proliferate at 20[degree]C to 30[degree]C, or as high temperature as 80[degree]C and higher. Spongiaria and tumicata have many symbiotic microorganisms, and genes equivalent to luminous bacteria genes were discovered in DNA of light emitting organs in luminous fishes. It was verified that animal groups in upwelling zones are supported by bacteria that assimilate inorganics supplied from ocean bottoms. Marine bacteria decompose almost all of organics brought in from land to sea, and those produced in sea. Marine bacteria engage in complex interrelations with other organisms for competition, antagonism, parasitism, and symbiosis. The bacteria make antibacterial substances, anti-algae bacteria, enzyme inhibitors, toxins, pharmacologically active substances, and such physiologically active substances as deposition promoting substances to undersea structures including shells and barnacles, and deposition blocking substances. 53 refs., 3 figs.

  13. Biosynthesis and characterization of polyhydroxyalkanoates produced by an extreme halophilic bacterium, Halomonas nitroreducens, isolated from hypersaline ponds.

    Science.gov (United States)

    Cervantes-Uc, J M; Catzin, J; Vargas, I; Herrera-Kao, W; Moguel, F; Ramirez, E; Rincón-Arriaga, S; Lizama-Uc, G

    2014-10-01

    Morphological, biochemical and genotypic characterization of a halophilic bacterium isolated from hypersaline ponds located at Las Coloradas (Río Lagartos, Yucatán, Mexico). Characterization of polymer produced by this strain was also performed. Twenty strains were isolated from water samples of salt ponds and selected based on both morphological features and their PHA storage capacity, which were determined by SEM and staining methods with Nile red and Nile blue, respectively; strains were also analysed by the fluorescence imaging technique. Among them, JCCOL25.8 strain showed the highest production of PHA's reason why phenotypic and genotypic characterization was performed; this strain was identified as Halomonas nitroreducens. Polymer produced by this strain was characterized by FTIR, DSC, GPC and EDX spectroscopy. Results indicated that the biosynthesized polymer was polyhydroxybutyrate (PHB) which had a melting peak at 170°C and a crystallinity percentage of about 36%. Based on phenotypic and genotypic aspects, JCCOL25.8 strain was identified as H. nitroreducens and it was capable to accumulate PHB. To our knowledge, there is only one study published on the biosynthesis of PHA's by H. nitroreducens strains, although the characterization of the obtained polymer was not reported. © 2014 The Society for Applied Microbiology.

  14. Methods of hydrolyzing a cellulose using halophilic, thermostable and ionic liquids tolerant cellulases

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Tao; Datta, Supratim; Simmons, Blake A.; Rubin, Edward M.

    2018-01-09

    The present invention provides for an isolated or recombinant polypeptide comprising an amino acid sequence having at least 70% identity with the amino acid sequence of a Halorhabdus utahensis cellulase, such as Hu-CBH1, wherein said amino acid sequence has a halophilic thermostable and/or thermophilic cellobiohydrolase (CBH) activity. In some embodiments, the polypeptide has a CBH activity that is resistant to up to about 20% of ionic liquids. The present invention also provides for compositions comprising and methods using the isolated or recombinant polypeptide.

  15. Characterization of exopolysaccharides produced by three moderately halophilic bacteria belonging to the family Alteromonadaceae.

    Science.gov (United States)

    Mata, J A; Béjar, V; Bressollier, P; Tallon, R; Urdaci, M C; Quesada, E; Llamas, I

    2008-08-01

    To study the exopolysaccharides (EPSs) produced by three novel moderately halophilic species belonging to the family Alteromonadaceae to optimize EPS yields, characterize their physical and chemical properties and evaluate possible biotechnological applications for these polymers. EPSs synthesized by Idiomarina fontislapidosi F32(T), Idiomarina ramblicola R22(T) and Alteromonas hispanica F23(T) were collected and analysed under optimum conditions: MY medium supplemented with 7.5% (w/v) salts; 32 degrees C; and 1% (w/v) glucose. Polymers were synthesized mainly during the early stationary growth phase with yields ranging from 1 to 1.5 g l(-1). The Idiomarina species each produced an anionic EPS composed mainly of glucose, mannose and galactose. A. hispanica synthesized an anionic EPS composed mainly of glucose, mannose and xylose. Solutions of all the polymers were low in viscosity and pseudoplastic in their behaviour. They showed emulsifying activity and the capacity to bind some metals. The Alteromonadaceae species studied in this work produced EPSs with physical and chemical properties different from those produced by other halophilic and nonhalophilic bacteria, suggesting that the wide diversity of micro-organisms being encountered nowadays in hypersaline environments offers enormous potential resources for biotechnological applications. We have optimized the EPS production and analysed new biopolymers produced by some recently described, moderately halophilic bacteria. These biopolymers are chemically and physically different from others already in use in biotechnology and offer hopes for new applications, especially in the case of A. hispanica, which may prove to be a viable source of xylo-oligosaccharides.

  16. Diversity of Extremely Halophilic Archaeal and Bacterial Communities from Commercial Salts.

    Science.gov (United States)

    Gibtan, Ashagrie; Park, Kyounghee; Woo, Mingyeong; Shin, Jung-Kue; Lee, Dong-Woo; Sohn, Jae Hak; Song, Minjung; Roh, Seong Woon; Lee, Sang-Jae; Lee, Han-Seung

    2017-01-01

    Salting is one of the oldest food preservation techniques. However, salt is also the source of living halophilic microorganisms that may affect human health. In order to determine the microbial communities of commercial salts, an investigation were done using amplicon sequencing approach in four commercial salts: Ethiopian Afdera salt (EAS), Ethiopian rock salt (ERS), Korean Jangpan salt (KJS), and Korean Topan salt (KTS). Using domain-specific primers, a region of the 16S rRNA gene was amplified and sequenced using a Roche 454 instrument. The results indicated that these microbial communities contained 48.22-61.4% Bacteria, 37.72-51.26% Archaea, 0.51-0.86% Eukarya, and 0.005-0.009% unclassified reads. Among bacteria, the communities in these salts were dominated by the phyla Proteobacteria, Bacteroidetes, Actinobacteria , and Firmicutes . Of the archaea, 91.58% belonged to the class Halobacteria , whereas the remaining 7.58, 0.83, and 0.01% were Nanoarchaea, Methanobacteria , and Thermococci , respectively. This comparison of microbial diversity in salts from two countries showed the presence of many archaeal and bacterial genera that occurred in salt samples from one country but not the other. The bacterial genera Enterobacter and Halovibrio were found only in Korean and Ethiopian salts, respectively. This study indicated the occurrence and diversity of halophilic bacteria and archaea in commercial salts that could be important in the gastrointestinal tract after ingestion.

  17. Microorganisms in potential host rocks for geological disposal of nuclear waste and their interactions with radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Cherkouk, A.; Liebe, M.; Luetke, L.; Moll, H.; Stumpf, T. [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Inst. of Resource Ecology

    2015-07-01

    The long-term safety of nuclear waste in a deep geological repository is an important issue in our society. Microorganisms indigenous to potential host rocks are able to influence the oxidation state, speciation and therefore the mobility of radionuclides as well as gas generation or canister corrosion. Therefore, for the safety assessment of such a repository it is necessary to know which microorganisms are present in the potential host rocks (e.g. clay, salt) and if these microorganisms can influence the performance of a repository. Microbial diversity in potential host rocks for geological disposal of nuclear waste was analyzed by culture-independent molecular biological methods (e.g. 16S rRNA gene retrieval) as well as enrichment and isolation of indigenous microbes. Among other isolates, a Paenibacillus strain, as a representative of Firmicutes, was recovered in R2A media under anaerobic conditions from Opalinus clay from the Mont Terri in Switzerland. Accumulation experiments and potentiometric titrations showed a strong interaction of Paenibacillus sp. cells with U(VI) within a broad pH range (3-7). Additionally, the interactions of the halophilic archaeal strain Halobacterium noricense DSM 15987, a salt rock representative reference strain, with U(VI) at high ionic strength was investigated. After 48 h the cells were still alive at uranium concentrations up to 60 μM, which demonstrates that Halobacterium noricense can tolerate uranium concentrations up to this level. The formed uranium sorption species were examined with time-resolved laser-induced fluorescence spectroscopy (TRLFS). The results about the microbial communities present in potential host rocks for nuclear waste repositories and their interactions with radionuclides contribute to the safety assessment of a prospective nuclear waste repository.

  18. Microorganisms in potential host rocks for geological disposal of nuclear waste and their interactions with radionuclides

    International Nuclear Information System (INIS)

    Cherkouk, A.; Liebe, M.; Luetke, L.; Moll, H.; Stumpf, T.

    2015-01-01

    The long-term safety of nuclear waste in a deep geological repository is an important issue in our society. Microorganisms indigenous to potential host rocks are able to influence the oxidation state, speciation and therefore the mobility of radionuclides as well as gas generation or canister corrosion. Therefore, for the safety assessment of such a repository it is necessary to know which microorganisms are present in the potential host rocks (e.g. clay, salt) and if these microorganisms can influence the performance of a repository. Microbial diversity in potential host rocks for geological disposal of nuclear waste was analyzed by culture-independent molecular biological methods (e.g. 16S rRNA gene retrieval) as well as enrichment and isolation of indigenous microbes. Among other isolates, a Paenibacillus strain, as a representative of Firmicutes, was recovered in R2A media under anaerobic conditions from Opalinus clay from the Mont Terri in Switzerland. Accumulation experiments and potentiometric titrations showed a strong interaction of Paenibacillus sp. cells with U(VI) within a broad pH range (3-7). Additionally, the interactions of the halophilic archaeal strain Halobacterium noricense DSM 15987, a salt rock representative reference strain, with U(VI) at high ionic strength was investigated. After 48 h the cells were still alive at uranium concentrations up to 60 μM, which demonstrates that Halobacterium noricense can tolerate uranium concentrations up to this level. The formed uranium sorption species were examined with time-resolved laser-induced fluorescence spectroscopy (TRLFS). The results about the microbial communities present in potential host rocks for nuclear waste repositories and their interactions with radionuclides contribute to the safety assessment of a prospective nuclear waste repository.

  19. Isolation and Identification of Phototrophic Microorganisms from Rudkhan Castle as a Biodeteriorating Agent

    Directory of Open Access Journals (Sweden)

    Parisa Mohammadi

    2016-09-01

    Full Text Available Introduction: Phototrophic microorganisms are the first residents of different surfaces of ancient buildings’ walls. These organisms can expand to provide the colonization of other microorganisms and to form microbial biofilms. During biofilm growth, acids and metabolites production bore the substratum and cause surfaces damages. Rudkan Castle, the historic monument located in Gilan province, an area with a humid climate has an appropriate surfaces to grow these microorganisms. Materials and methods: In this study, morphological identification of algae and cyanobacteria which was isolated from different areas of the brick walls of Castle has been investigated. Samples were taken from 24 different areas of Castle walls and were aseptically cultured into Blue Green Medium (BGM and Bolds Basal Medium (BBM, and colonies were observed using light microscopy. Results: The dominant organisms which were isolated and identified, were Cladophora, Trentepohlia, Klebsormidium, Trebouxia, Pleurastrum, Chlorococcum as chlorophyta order and Scytonema, Tolypothrix, Leptolyngbya, Plectolyngbya, Phormidium, Gloeocapsa, Microcoleus, Nostoc as a cyanobacteria order. Discussion and conclusion: As expected, diversity of a large number of cyanobacteria and algae phototrophs was isolated. Diversity of organisms on the surface of monuments depends on many factors, including the weather condition such as moisture, the amount of radiation absorbed by the surface, temperature of area, the materials used in the monuments, the biological acceptance of surface and presence of variety of organisms in the soil surface and the air on. Study of destructive factors is the first step toward the protection and restoration of ancient monuments.

  20. Virgibacillus ainsalahensis sp. nov., a Moderately Halophilic Bacterium Isolated from Sediment of a Saline Lake in South of Algeria.

    Science.gov (United States)

    Amziane, Meriam; Darenfed-Bouanane, Amel; Abderrahmani, Ahmed; Selama, Okba; Jouadi, Lydia; Cayol, Jean-Luc; Nateche, Farida; Fardeau, Marie-Laure

    2017-02-01

    A Gram-positive, moderately halophilic, endospore-forming bacterium, designated MerV T , was isolated from a sediment sample of a saline lake located in Ain Salah, south of Algeria. The cells were rod shaped and motile. Isolate MerV T grew at salinity interval of 0.5-25% NaCl (optimum, 5-10%), pH 6.0-12.0 (optimum, 8.0), and temperature between 10 and 40 °C (optimum, 30 °C).The polar lipids comprised diphosphatidylglycerol, phosphatidylglycerol, a glycolipid, a phospholipid, and two lipids, and MK-7 is the predominant menaquinone. The predominant cellular fatty acids were anteiso C 15:0 and anteiso C 17:0 . The DNA G+C content was 45.3 mol%. Phylogenetic analysis based on 16S rRNA gene sequence comparisons revealed that strain MerV T was most closely related to Virgibacillus halodenitrificans (gene sequence similarity of 97.0%). On the basis of phenotypic, chemotaxonomic properties, and phylogenetic analyses, strain MerV T (=DSM = 28944 T ) should be placed in the genus Virgibacillus as a novel species, for which the name Virgibacillus ainsalahensis is proposed.

  1. Comparison of two extreme halophilic Halobacterium noricense strains on DNA and protein level

    Energy Technology Data Exchange (ETDEWEB)

    Bader, Miriam; Cherkouk, Andrea [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). HZDR Young Investigator Group; Flemming, Katrin [Helmholtz-Zentrum Dresden-Rossendorf e.V., Dresden (Germany). Biogeochemistry; Swanson, J.S. [Los Alamos National Laboratory, Carlsbad, NM (United States)

    2017-06-01

    Two strains of the halophilic archaeon Halobacterium noricense isolated from rock salt of different locations were used for interaction studies with uranium. It was found that both strains showed similar, atypical bioassociation kinetics accompanied by cell agglomeration as a stress response. The 16S rRNA gene sequences of both strains had a high similarity (> 99 %). However, differences in the whole protein pattern were apparent.

  2. Comparison of two extreme halophilic Halobacterium noricense strains on DNA and protein level

    International Nuclear Information System (INIS)

    Bader, Miriam; Cherkouk, Andrea

    2017-01-01

    Two strains of the halophilic archaeon Halobacterium noricense isolated from rock salt of different locations were used for interaction studies with uranium. It was found that both strains showed similar, atypical bioassociation kinetics accompanied by cell agglomeration as a stress response. The 16S rRNA gene sequences of both strains had a high similarity (> 99 %). However, differences in the whole protein pattern were apparent.

  3. Halophilic archaea on Earth and in space: growth and survival under extreme conditions.

    Science.gov (United States)

    Oren, Aharon

    2014-12-13

    Salts are abundant on Mars, and any liquid water that is present or may have been present on the planet is expected to be hypersaline. Halophilic archaea (family Halobacteriaceae) are the microorganisms best adapted to life at extremes of salinity on Earth. This paper reviews the properties of the Halobacteriaceae that may make the group good candidates for life also on Mars. Many species resist high UV and gamma radiation levels; one species has survived exposure to vacuum and radiation during a space flight; and there is at least one psychrotolerant species. Halophilic archaea may survive for millions of years within brine inclusions in salt crystals. Many species have different modes of anaerobic metabolism, and some can use light as an energy source using the light-driven proton pump bacteriorhodopsin. They are also highly tolerant to perchlorate, recently shown to be present in Martian soils, and some species can even use perchlorate as an electron acceptor to support anaerobic growth. The presence of characteristic carotenoid pigments (α-bacterioruberin and derivatives) makes the Halobacteriaceae easy to identify by Raman spectroscopy. Thus, if present on Mars, such organisms may be detected by Raman instrumentation planned to explore Mars during the upcoming ExoMars mission. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

  4. The potential of halophilic and halotolerant bacteria for the production of antineoplastic enzymes: L-asparaginase and L-glutaminase.

    Science.gov (United States)

    Shirazian, Pejman; Asad, Sedigheh; Amoozegar, Mohammad Ali

    2016-01-01

    L-asparaginase and L-glutaminase can be effectively used for the treatment of patients who suffer from accute lymphoblastic leukemia and tumor cells. Microbial sources are the best source for the bulk production of these enzymes. However, their long-term administration may cause immunological responses, so screening for new enzymes with novel properties is required. Halophilic and halotolerant bacteria with novel enzymatic characteristics can be considered as a potential source for production of enzymes with different immunological properties. In this study, L-asparaginase and L-glutaminase production by halophilic bacteria isolated from Urmia salt lake was studied. Out of the 85 isolated halophilic and halotolerant bacterial strains, 16 (19 %) showed L-asparaginase activity and 3 strains (3.5 %) showed L-glutaminase activity. Strains with the highest activities were selected for further studies. Based on 16S rDNA sequence analysis, it was shown that the selected isolates for L-asparaginase and L-glutaminase production belong to the genus Bacillus and Salicola, respectively. Both enzymes were produced extracellularly. The strain with the most L-asparaginase production did not show L-glutaminase production which is medically important. The effects of key parameters including temperature, initial pH of the solution, and concentrations of glucose, asparagine or glutamine, and sodium chloride were evaluated by means of response surface methodology (RSM) to optimize enzymes production. Under the obtained optimal conditions, L-asparaginase and L-glutaminase production was increased up to 1.5 (61.7 unit/mL) and 2.6 fold (46.4 unit/mL), respectively.

  5. Investigation and Isolation of Cellulase-Producing microorganisms in the Red Sea

    KAUST Repository

    Fatani, Siham

    2016-05-01

    Cellulolytic microorganisms are considered to be key players in biorefinery, especially for the utilization of plant biomass. These organisms have been isolated from various environments. The Red Sea is one of the seas with high biodiversity and a unique environment, characterized by high water temperature and high salinity . However, there is little information regarding cellulases in Red Sea environments. The aim of the present study is to evaluate the Red Sea as a gene resource for microbial cellulase. I first surveyed microbial cellulases in the Red Sea using a method called metagenomes, and then investigated their abundance and diversity. My survey revealed that the Red Sea biome has a substantial abundance and a wide range of cellulase enzymes with substantial abundance, when compared with those in other environments. Next, I tried to isolate cellulase-active microorganisms from the Red Sea and I successfully obtained seven strains of four different taxonomic groups. These strains showed a similarity of 99% identity to Aspergillus ustus, 99% to Staphylococcus pasteuri, 99% to Bacillus aerius and 99% to Bacillus subtilis. The enzyme assay I conducted, revealed that these strains actually secreted active cellulases. These results suggest that the Red Sea environment can be, indeed, an excellent gene resource of microbial cellulases.

  6. Radiation-resistant micro-organisms isolated from textiles

    International Nuclear Information System (INIS)

    Kristensen, H.; Christensen, E.A.

    1981-01-01

    Towels from private homes and public offices and underwear contaminated by being used by employees at a public health laboratory were examined for occurrence of radiation-resistant bacteria and fungi. Three different methods were used for isolation of the most resistant organisms, one with multiplication of the microbial population prior to an irradiation used for selection, and two witout this multiplication and with the organisms placed on membrane filters or in situ on the textiles, respectively. A total of 44 different strains were isolated. Differences in the three methods used for selection of the most radiation-resistant microorganisms were not reflected in the results. 16 pigmentproducing Gram-positive cocci, tentatively classified as Micrococcus radiodurans, were the most radiation-resistant and were isolated in about half of the examinations. Other Gram-positive cocci, nonspore forming rods, some Nocardia and Candida parapsilosis strains and two Bacillus strains constituted the rest of the collection. With few exceptions dose-response curves for the strains were upward convex. D-6 values determined to be between 1.5 megarad for the most radiation sensitive, a Candida, and 5.7 megarad for the most resistant, tentatively classified as M. radiodurans. The D-6 values for the Bacillus strains were in both cases 1.8 megarad, consistent with a D-value of 0.3 megarad. The same resistance is reported to be the maximum resistance for B. pumilus, strain E601, commonly used as reference strain in the literature on radiation sterilization of medical devices and supplies. (author)

  7. Radiation-resistant micro-organisms isolated from textiles

    Energy Technology Data Exchange (ETDEWEB)

    Kristensen, H; Christensen, E A [Statens Seruminstitut, Copenhagen (Denmark)

    1981-01-01

    Towels from private homes and public offices and underwear contaminated by being used by employees at a public health laboratory were examined for occurrence of radiation-resistant bacteria and fungi. Three different methods were used for isolation of the most resistant organisms, one with multiplication of the microbial population prior to an irradiation used for selection, and two witout this multiplication and with the organisms placed on membrane filters or in situ on the textiles, respectively. A total of 44 different strains were isolated. Differences in the three methods used for selection of the most radiation-resistant microorganisms were not reflected in the results. 16 pigmentproducing Gram-positive cocci, tentatively classified as Micrococcus radiodurans, were the most radiation-resistant and were isolated in about half of the examinations. Other Gram-positive cocci, nonspore forming rods, some Nocardia and Candida parapsilosis strains and two Bacillus strains constituted the rest of the collection. With few exceptions dose-response curves for the strains were upward convex. D-6 values determined to be between 1.5 megarad for the most radiation sensitive, a Candida, and 5.7 megarad for the most resistant, tentatively classified as M. radiodurans. The D-6 values for the Bacillus strains were in both cases 1.8 megarad, consistent with a D-value of 0.3 megarad. The same resistance is reported to be the maximum resistance for B. pumilus, strain E601, commonly used as reference strain in the literature on radiation sterilization of medical devices and supplies.

  8. Osmoadaptative Strategy and Its Molecular Signature in Obligately Halophilic Heterotrophic Protists.

    Science.gov (United States)

    Harding, Tommy; Brown, Matthew W; Simpson, Alastair G B; Roger, Andrew J

    2016-08-03

    Halophilic microbes living in hypersaline environments must counteract the detrimental effects of low water activity and salt interference. Some halophilic prokaryotes equilibrate their intracellular osmotic strength with the extracellular milieu by importing inorganic solutes, mainly potassium. These "salt-in" organisms characteristically have proteins that are highly enriched with acidic and hydrophilic residues. In contrast, "salt-out" halophiles accumulate large amounts of organic solutes like amino acids, sugars and polyols, and lack a strong signature of halophilicity in the amino acid composition of cytoplasmic proteins. Studies to date have examined halophilic prokaryotes, yeasts, or algae, thus virtually nothing is known about the molecular adaptations of the other eukaryotic microbes, that is, heterotrophic protists (protozoa), that also thrive in hypersaline habitats. We conducted transcriptomic investigations to unravel the molecular adaptations of two obligately halophilic protists, Halocafeteria seosinensis and Pharyngomonas kirbyi Their predicted cytoplasmic proteomes showed increased hydrophilicity compared with marine protists. Furthermore, analysis of reconstructed ancestral sequences suggested that, relative to mesophiles, proteins in halophilic protists have undergone fewer substitutions from hydrophilic to hydrophobic residues since divergence from their closest relatives. These results suggest that these halophilic protists have a higher intracellular salt content than marine protists. However, absence of the acidic signature of salt-in microbes suggests that Haloc. seosinensis and P. kirbyi utilize organic osmolytes to maintain osmotic equilibrium. We detected increased expression of enzymes involved in synthesis and transport of organic osmolytes, namely hydroxyectoine and myo-inositol, at maximal salt concentration for growth in Haloc. seosinensis, suggesting possible candidates for these inferred organic osmolytes. © The Author 2016

  9. New insight in the structural features of haloadaptation in α-amylases from halophilic Archaea following homology modeling strategy: folded and stable conformation maintained through low hydrophobicity and highly negative charged surface

    Science.gov (United States)

    Zorgani, Mohamed Amine; Patron, Kevin; Desvaux, Mickaël

    2014-07-01

    Proteins from halophilic archaea, which live in extreme saline conditions, have evolved to remain folded, active and stable at very high ionic strengths. Understanding the mechanism of haloadaptation is the first step toward engineering of halostable biomolecules. Amylases are one of the main enzymes used in industry. Yet, no three-dimensional structure has been experimentally resolved for α-amylases from halophilic archaea. In this study, homology structure modeling of α-amylases from the halophilic archaea Haloarcula marismortui, Haloarcula hispanica, and Halalkalicoccus jeotgali were performed. The resulting models were subjected to energy minimization, evaluation, and structural analysis. Calculations of the amino acid composition, salt bridges and hydrophobic interactions were also performed and compared to a set of non-halophilic counterparts. It clearly appeared that haloarchaeal α-amylases exhibited lower propensities for helix formation and higher propensities for coil-forming regions. Furthermore, they could maintain a folded and stable conformation in high salt concentration through highly negative charged surface with over representation of acidic residues, especially Asp, and low hydrophobicity with increase of salt bridges and decrease in hydrophobic interactions on the protein surface. This study sheds some light on the stability of α-amylases from halophilic archaea and provides strong basis not only to understand haloadaptation mechanisms of proteins in microorganisms from hypersalines environments but also for biotechnological applications.

  10. Structural basis for the aminoacid composition of proteins from halophilic archea.

    Directory of Open Access Journals (Sweden)

    Xavier Tadeo

    2009-12-01

    Full Text Available Proteins from halophilic organisms, which live in extreme saline conditions, have evolved to remain folded at very high ionic strengths. The surfaces of halophilic proteins show a biased amino acid composition with a high prevalence of aspartic and glutamic acids, a low frequency of lysine, and a high occurrence of amino acids with a low hydrophobic character. Using extensive mutational studies on the protein surfaces, we show that it is possible to decrease the salt dependence of a typical halophilic protein to the level of a mesophilic form and engineer a protein from a mesophilic organism into an obligate halophilic form. NMR studies demonstrate complete preservation of the three-dimensional structure of extreme mutants and confirm that salt dependency is conferred exclusively by surface residues. In spite of the statistically established fact that most halophilic proteins are strongly acidic, analysis of a very large number of mutants showed that the effect of salt on protein stability is largely independent of the total protein charge. Conversely, we quantitatively demonstrate that halophilicity is directly related to a decrease in the accessible surface area.

  11. An x-ray absorption spectroscopy study of Cd binding onto a halophilic archaeon

    International Nuclear Information System (INIS)

    Showalter, Allison R; Bunker, Bruce A; Szymanowski, Jennifer E S; Fein, Jeremy B

    2016-01-01

    X-ray absorption spectroscopy (XAS) and cadmium (Cd) isotherm experiments determine how Cd adsorbs to the surface of halophilic archaeon Halobacterium noricense . This archaeon, isolated from the Waste Isolation Pilot Plant (WIPP) near Carlsbad, New Mexico could be involved with the transport of toxic metals stored in the transuranic waste in the salt mine. The isotherm experiments show that adsorption is relatively constant across the tolerable pH range for H. noricense . The XAS results indicate that Cd adsorption occurs predominately via a sulfur site, most likely sulfhydryl, with the same site dominating all measured pH values. (paper)

  12. An x-ray absorption spectroscopy study of Cd binding onto a halophilic archaeon

    Science.gov (United States)

    Showalter, Allison R.; Szymanowski, Jennifer E. S.; Fein, Jeremy B.; Bunker, Bruce A.

    2016-05-01

    X-ray absorption spectroscopy (XAS) and cadmium (Cd) isotherm experiments determine how Cd adsorbs to the surface of halophilic archaeon Halobacterium noricense. This archaeon, isolated from the Waste Isolation Pilot Plant (WIPP) near Carlsbad, New Mexico could be involved with the transport of toxic metals stored in the transuranic waste in the salt mine. The isotherm experiments show that adsorption is relatively constant across the tolerable pH range for H. noricense. The XAS results indicate that Cd adsorption occurs predominately via a sulfur site, most likely sulfhydryl, with the same site dominating all measured pH values.

  13. Gracilibacillus aidingensis sp. nov., a novel moderately halophilic bacterium isolated from Aiding salt lake.

    Science.gov (United States)

    Guan, Tong-Wei; Tian, Lei; Li, En-Yuan; Tang, Shu-Kun; Zhang, Xiao-Ping

    2017-11-01

    A novel Gram-positive, aerobe, moderately halophilic bacterium was isolated from saline soil of Aiding lake in Xinjiang, north-west of China, designated strain YIM 98001 T . Cells were rod-shaped, motile and grew at 5-20% (w/v) NaCl (optimum 10%), pH 6-10 (optimum pH 7.0) and 4-45 °C (optimum 37 °C). The major cellular fatty acids were anteiso C 15:0 , anteiso C 17:0 , iso C 15:0 . The predominant respiratory quinone was MK-7. Diphosphatidylglycerol, phosphatidylglycerol, phosphoglycolipid were the major polar lipids. Meso-diaminopimelic acid was the diagnostic diamino acid of the cell-wall peptidoglycan. The G+C content was 36.46 mol%. 16S rRNA gene sequence analysis showed that the strain belongs to the family Bacillaceae, with the highest sequence similarity to the type strain Gracilibacillus thailandensis TP2-8 T (96.84%), followed by Gracilibacillus saliphilus YIM 91119 T (96.78%) and Gracilibacillus ureilyticus MF38 T (96.57%), thus confirming the affiliation of strain YIM 98001 T to the genus Gracilibacillus. The polyphasic approach indicates that strain YIM 98001 T represents a novel species of the genus Gracilibacillus, for which the name Gracilibacillus aidingensis is proposed. The type strain is YIM 98001 T (=KCTC 42683 T  = DSMZ 104330 T ).

  14. Complete Genome Sequence of the Halophilic Methylotrophic Methanogen Archaeon Methanohalophilus portucalensis Strain FDF-1T

    KAUST Repository

    L’Haridon, Stéphane

    2018-01-17

    We report here the complete genome sequence (2.08 Mb) of Methanohalophilus portucalensis strain FDF-1T, a halophilic methylotrophic methanogen isolated from the sediment of a saltern in Figeria da Foz, Portugal. The average nucleotide identity and DNA-DNA hybridization analyses show that Methanohalophilus mahii, M. halophilus, and M. portucalensis are three different species within the Methanosarcinaceae family.

  15. Complete Genome Sequence of the Halophilic Methylotrophic Methanogen Archaeon Methanohalophilus portucalensis Strain FDF-1T

    KAUST Repository

    L’ Haridon, Sté phane; Corre, Erwan; Guan, Yue; Vinu, Manikandan; La Cono, Violetta; Yakimov, Michail; Stingl, Ulrich; Toffin, Laurent; Jebbar, Mohamed

    2018-01-01

    We report here the complete genome sequence (2.08 Mb) of Methanohalophilus portucalensis strain FDF-1T, a halophilic methylotrophic methanogen isolated from the sediment of a saltern in Figeria da Foz, Portugal. The average nucleotide identity and DNA-DNA hybridization analyses show that Methanohalophilus mahii, M. halophilus, and M. portucalensis are three different species within the Methanosarcinaceae family.

  16. Corrosion of aluminum alloy 2024 by microorganisms isolated from aircraft fuel tanks.

    Science.gov (United States)

    McNamara, Christopher J; Perry, Thomas D; Leard, Ryan; Bearce, Ktisten; Dante, James; Mitchell, Ralph

    2005-01-01

    Microorganisms frequently contaminate jet fuel and cause corrosion of fuel tank metals. In the past, jet fuel contaminants included a diverse group of bacteria and fungi. The most common contaminant was the fungus Hormoconis resinae. However, the jet fuel community has been altered by changes in the composition of the fuel and is now dominated by bacterial contaminants. The purpose of this research was to determine the composition of the microbial community found in fuel tanks containing jet propellant-8 (JP-8) and to determine the potential of this community to cause corrosion of aluminum alloy 2024 (AA2024). Isolates cultured from fuel tanks containing JP-8 were closely related to the genus Bacillus and the fungi Aureobasidium and Penicillium. Biocidal activity of the fuel system icing inhibitor diethylene glycol monomethyl ether is the most likely cause of the prevalence of endospore forming bacteria. Electrochemical impedance spectroscopy and metallographic analysis of AA2024 exposed to the fuel tank environment indicated that the isolates caused corrosion of AA2024. Despite the limited taxonomic diversity of microorganisms recovered from jet fuel, the community has the potential to corrode fuel tanks.

  17. Antimicrobial Sensitivity Pattern of Microorganisms Isolated from Vaginal Infections at a Tertiary Hospital in Bangalore, India

    Directory of Open Access Journals (Sweden)

    Nagalakshmi Narayana-Swamy

    2015-03-01

    Full Text Available Background: The vagina contains dozens of microbiological species in variable quantities and is, therefore, considered a complex environment. Among the microorganisms, bacteria have important repercussions on women’s health. The present study was conducted especially to elucidate this type of vaginal isolates and their sensitivity towards currently used antibiotics. Methods: This was a retrospective study conducted at the Department of Obstetrics and Gynaecology, Sapthagiri Hospital, Bangalore, India from January 2012 to December 2013. All symptomatic women who had a high vaginal swab taken for culture and sensitivity testing were included in this study. Antibiotic susceptibility was tested using disc diffusion method (modified Kirby-Bauer method. The antibiotic sensitivity patterns of isolated microorganisms were studied. Results: Out of 200 patients, 95% had positive vaginal cultures. Fifteen types of microorganisms were isolated. The highest frequency of infection was observed at the age of 20-30 years, followed by 41-50 years and 31-40 years, and a low frequency of infection was observed above 50 years of age. The most prevalent pathogen was Escherichia coli, followed by Streptococcus agalactiae and diphtheroids with equal incidence. Among the antibiotics tested, isolated pathogens were completely resistant to nalidixic acid and highly sensitive to meropenem and imepenem. Conclusion: The high prevalence of gynaecological infections demands that patients with symptoms undergo thorough investigation with cultures and sensitivity essays. Changes in treatment protocols are required to treat vaginal infections effectively.

  18. Insights into Head-Tailed Viruses Infecting Extremely Halophilic Archaea

    Science.gov (United States)

    Pietilä, Maija K.; Laurinmäki, Pasi; Russell, Daniel A.; Ko, Ching-Chung; Jacobs-Sera, Deborah; Butcher, Sarah J.

    2013-01-01

    Extremophilic archaea, both hyperthermophiles and halophiles, dominate in habitats where rather harsh conditions are encountered. Like all other organisms, archaeal cells are susceptible to viral infections, and to date, about 100 archaeal viruses have been described. Among them, there are extraordinary virion morphologies as well as the common head-tailed viruses. Although approximately half of the isolated archaeal viruses belong to the latter group, no three-dimensional virion structures of these head-tailed viruses are available. Thus, rigorous comparisons with bacteriophages are not yet warranted. In the present study, we determined the genome sequences of two of such viruses of halophiles and solved their capsid structures by cryo-electron microscopy and three-dimensional image reconstruction. We show that these viruses are inactivated, yet remain intact, at low salinity and that their infectivity is regained when high salinity is restored. This enabled us to determine their three-dimensional capsid structures at low salinity to a ∼10-Å resolution. The genetic and structural data showed that both viruses belong to the same T-number class, but one of them has enlarged its capsid to accommodate a larger genome than typically associated with a T=7 capsid by inserting an additional protein into the capsid lattice. PMID:23283946

  19. Antagonistic Properties of Some Halophilic Thermoactinomycetes Isolated from Superficial Sediment of a Solar Saltern and Production of Cyclic Antimicrobial Peptides by the Novel Isolate Paludifilum halophilum

    Science.gov (United States)

    Frikha Dammak, Donyez; Zarai, Ziad; Najah, Soumaya; Abdennabi, Rayed; Belbahri, Lassaad; Rateb, Mostafa E.; Mejdoub, Hafedh

    2017-01-01

    This study has focused on the isolation of twenty-three halophilic actinomycetes from two ponds of different salinity and the evaluation of their ability to exert an antimicrobial activity against both their competitors and several other pathogens. From the 23 isolates, 18 strains showed antagonistic activity, while 19 showed activities against one or more of the seven pathogen strains tested. Six strains exhibited consistent antibacterial activity against Gram-negative and Gram-positive pathogens characterized at the physiological and molecular levels. These strains shared only 94-95% 16S rRNA sequence identity with the closely related species of the Thermoactinomycetaceae family. Among them, the potent strain SMBg3 was further characterized and assigned to a new genus in the family for which the name Paludifilum halophilum (DSM 102817T) is proposed. Sequential extraction of the antimicrobial compounds with ethyl acetate revealed that the crude extract from SMBg3 strain had inhibitory effect on the growth of the plant pathogen Agrobacterium tumefaciens and the human pathogens Staphylococcus aureus, Salmonella enterica, Escherichia coli, and Pseudomonas aeruginosa. Based on the HRESI-MS spectral data, the cyclic lipopeptide Gramicidin S and four cyclic dipeptides (CDPs) named cyclo(L-4-OH-Pro-L-Leu), cyclo(L-Tyr-L-Pro), cyclo(L-Phe-L-Pro), and cyclo(L-Leu-L-Pro) were detected in the fermentation broth of Paludifilum halophilum. To our knowledge, this is the first report on the isolation of these compounds from members of the Thermoactinomycetaceae family. PMID:28819625

  20. High quality draft genome sequence of the moderately halophilic bacterium Pontibacillus yanchengensis Y32(T) and comparison among Pontibacillus genomes.

    Science.gov (United States)

    Huang, Jing; Qiao, Zi Xu; Tang, Jing Wei; Wang, Gejiao

    2015-01-01

    Pontibacillus yanchengensis Y32(T) is an aerobic, motile, Gram-positive, endospore-forming, and moderately halophilic bacterium isolated from a salt field. In this study, we describe the features of P. yanchengensis strain Y32(T) together with a comparison with other four Pontibacillus genomes. The 4,281,464 bp high-quality-draft genome of strain Y32(T) is arranged into 153 contigs containing 3,965 protein-coding genes and 77 RNA encoding genes. The genome of strain Y32(T) possesses many genes related to its halophilic character, flagellar assembly and chemotaxis to support its survival in a salt-rich environment.

  1. Cloning, Characterization and Analysis of cat and ben Genes from the Phenol Degrading Halophilic Bacterium Halomonas organivorans

    Science.gov (United States)

    Moreno, Maria de Lourdes; Sánchez-Porro, Cristina; Piubeli, Francine; Frias, Luciana; García, María Teresa; Mellado, Encarnación

    2011-01-01

    Background Extensive use of phenolic compounds in industry has resulted in the generation of saline wastewaters that produce significant environmental contamination; however, little information is available on the degradation of phenolic compounds in saline conditions. Halomonas organivorans G-16.1 (CECT 5995T) is a moderately halophilic bacterium that we isolated in a previous work from saline environments of South Spain by enrichment for growth in different pollutants, including phenolic compounds. PCR amplification with degenerate primers revealed the presence of genes encoding ring-cleaving enzymes of the β-ketoadipate pathway for aromatic catabolism in H. organivorans. Findings The gene cluster catRBCA, involved in catechol degradation, was isolated from H. organivorans. The genes catA, catB, catC and the divergently transcribed catR code for catechol 1,2-dioxygenase (1,2-CTD), cis,cis-muconate cycloisomerase, muconolactone delta-isomerase and a LysR-type transcriptional regulator, respectively. The benzoate catabolic genes (benA and benB) are located flanking the cat genes. The expression of cat and ben genes by phenol and benzoic acid was shown by RT-PCR analysis. The induction of catA gene by phenol and benzoic acid was also probed by the measurement of 1,2-CTD activity in H. organivorans growth in presence of these inducers. 16S rRNA and catA gene-based phylogenies were established among different degrading bacteria showing no phylogenetic correlation between both genes. Conclusions/Significance In this work, we isolated and determined the sequence of a gene cluster from a moderately halophilic bacterium encoding ortho-pathway genes involved in the catabolic metabolism of phenol and analyzed the gene organization, constituting the first report characterizing catabolic genes involved in the degradation of phenol in moderate halophiles, providing an ideal model system to investigate the potential use of this group of extremophiles in the decontamination of

  2. Multistage bioassociation of uranium onto an extremely halophilic archaeon revealed by a unique combination of spectroscopic and microscopic techniques

    Energy Technology Data Exchange (ETDEWEB)

    Bader, Miriam; Müller, Katharina; Foerstendorf, Harald; Drobot, Björn [Helmholtz-Zentrum Dresden – Rossendorf, Institute of Resource Ecology, Bautzner Landstraße 400, 01328 Dresden (Germany); Schmidt, Matthias; Musat, Niculina [Helmholtz Centre for Environmental Research–UFZ, Department of Isotope Biogeochemistry, Permoserstraße 15, 04318 Leipzig (Germany); Swanson, Juliet S.; Reed, Donald T. [Los Alamos National Laboratory, Repository Science and Operations, 1400 University Drive, Carlsbad, NM, 88220 (United States); Stumpf, Thorsten [Helmholtz-Zentrum Dresden – Rossendorf, Institute of Resource Ecology, Bautzner Landstraße 400, 01328 Dresden (Germany); Cherkouk, Andrea, E-mail: a.cherkouk@hzdr.de [Helmholtz-Zentrum Dresden – Rossendorf, Institute of Resource Ecology, Bautzner Landstraße 400, 01328 Dresden (Germany)

    2017-04-05

    Highlights: • First prolonged kinetics study of uranium to halophilic archaea was performed. • An atypical time-dependent bioassociation behavior of uranium was observed. • Unique combination of spectroscopic and microscopic methods was used. • In situ ATR FT-IR showed association of U(VI) to phosphoryl and carboxylate groups. • Time-dependent changes of U(VI) localization could be monitored by SEM/EDX. - Abstract: The interactions of two extremely halophilic archaea with uranium were investigated at high ionic strength as a function of time, pH and uranium concentration. Halobacterium noricense DSM-15987 and Halobacterium sp. putatively noricense, isolated from the Waste Isolation Pilot Plant repository, were used for these investigations. The kinetics of U(VI) bioassociation with both strains showed an atypical multistage behavior, meaning that after an initial phase of U(VI) sorption, an unexpected interim period of U(VI) release was observed, followed by a slow reassociation of uranium with the cells. By applying in situ attenuated total reflection Fourier-transform infrared spectroscopy, the involvement of phosphoryl and carboxylate groups in U(VI) complexation during the first biosorption phase was shown. Differences in cell morphology and uranium localization become visible at different stages of the bioassociation process, as shown with scanning electron microscopy in combination with energy dispersive X-ray spectroscopy. Our results demonstrate for the first time that association of uranium with the extremely halophilic archaeon is a multistage process, beginning with sorption and followed by another process, probably biomineralization.

  3. Multistage bioassociation of uranium onto an extremely halophilic archaeon revealed by a unique combination of spectroscopic and microscopic techniques

    International Nuclear Information System (INIS)

    Bader, Miriam; Müller, Katharina; Foerstendorf, Harald; Drobot, Björn; Schmidt, Matthias; Musat, Niculina; Swanson, Juliet S.; Reed, Donald T.; Stumpf, Thorsten; Cherkouk, Andrea

    2017-01-01

    Highlights: • First prolonged kinetics study of uranium to halophilic archaea was performed. • An atypical time-dependent bioassociation behavior of uranium was observed. • Unique combination of spectroscopic and microscopic methods was used. • In situ ATR FT-IR showed association of U(VI) to phosphoryl and carboxylate groups. • Time-dependent changes of U(VI) localization could be monitored by SEM/EDX. - Abstract: The interactions of two extremely halophilic archaea with uranium were investigated at high ionic strength as a function of time, pH and uranium concentration. Halobacterium noricense DSM-15987 and Halobacterium sp. putatively noricense, isolated from the Waste Isolation Pilot Plant repository, were used for these investigations. The kinetics of U(VI) bioassociation with both strains showed an atypical multistage behavior, meaning that after an initial phase of U(VI) sorption, an unexpected interim period of U(VI) release was observed, followed by a slow reassociation of uranium with the cells. By applying in situ attenuated total reflection Fourier-transform infrared spectroscopy, the involvement of phosphoryl and carboxylate groups in U(VI) complexation during the first biosorption phase was shown. Differences in cell morphology and uranium localization become visible at different stages of the bioassociation process, as shown with scanning electron microscopy in combination with energy dispersive X-ray spectroscopy. Our results demonstrate for the first time that association of uranium with the extremely halophilic archaeon is a multistage process, beginning with sorption and followed by another process, probably biomineralization.

  4. Biotechnological applications of halophilic lipases and thioesterases.

    Science.gov (United States)

    Schreck, Steven D; Grunden, Amy M

    2014-02-01

    Lipases and esterases are enzymes which hydrolyze ester bonds between a fatty acid moiety and an esterified conjugate, such as a glycerol or phosphate. These enzymes have a wide spectrum of use in industrial applications where their high activity, broad substrate specificity, and stability under harsh conditions have made them integral in biofuel production, textile processing, waste treatment, and as detergent additives. To date, these industrial applications have mainly leveraged enzymes from mesophilic and thermophilic organisms. However, increasingly, attention has turned to halophilic enzymes as catalysts in environments where high salt stability is desired. This review provides a brief overview of lipases and esterases and examines specific structural motifs and evolutionary adaptations of halophilic lipases. Finally, we examine the state of research involving these enzymes and provide an in-depth look at an exciting algal-based biofuel production system. This system uses a recombinant halophilic lipase to increase oil production efficiency by cleaving algal fatty acids from the acyl carrier protein, which eliminates feedback inhibition of fatty acid synthesis.

  5. Analysis of Carotenoid Production by Halorubrum sp. TBZ126; an Extremely Halophilic Archeon from Urmia Lake

    Directory of Open Access Journals (Sweden)

    Davood Naziri

    2014-03-01

    Full Text Available Purpose: Carotenoids are of great interest in many scientific disciplines because of their wide distribution, diverse functions and interesting properties. The present report describes a new natural source for carotenoid production. Methods: Halorubrum sp., TBZ126, an extremely halophilic archaeon, was isolated from Urmia Lack following culture of water sample on marine agar medium and incubation at 30 °C. Then single colonies were cultivated in broth media. After that the cells were collected and carotenoids were extracted with acetone-methanol (7:3 v/v. The identification of carotenoids was performed by UV-VIS spectroscopy and confirmed by thin layer chromatography (TLC in the presence of antimony pentachloride (SbCl5. The production profile was analyzed using liquid-chromatography mass spectroscopy (LC-MS techniques. Phenotypic characteristics of the isolate were carried out and the 16S rRNA gene was amplified using polymerase chain reaction (PCR. Results: LC-MS analytical results revealed that produced carotenoids are bacterioruberin, lycopene and β-carotene. Bacterioruberin was found to be the predominant produced carotenoid. 16S rRNA analysis showed that TBZ126 has 100% similarity with Halorubrum chaoviator Halo-G*T (AM048786. Conclusion: Halorubrum sp. TBZ126, isolated from Urmia Lake has high capacity in the production of carotenoids. This extremely halophilic archaeon could be considered as a prokaryotic candidate for carotenoid production source for future studies.

  6. The impact of the types of microorganisms isolated from blood and wounds on the results of treatment in burn patients with sepsis.

    Science.gov (United States)

    Glik, Justyna; Kawecki, Marek; Gaździk, Tadeusz; Nowak, Mariusz

    2012-01-01

    Despite development of combustiology, infections continue to be the most important cause of death among patients with burns. Sepsis is the most severe clinical presentation of infection in patients after thermal injuries who require immediate treatment. Early diagnosis and proper treatment of sepsis are important in the clinical management that is often hampered for multiple reasons, e.g. impaired patient immunity, problems with microorganisms with multi-antibacterial drug resistance. The aim of the study was to assess effect of type of a microorganism isolated from blood and wound on results of treatment of sepsis in patients with burns. Effect of type of microorganisms isolated from blood and wound on the result of treatment of sepsis was studied in 338 patients hospitalized immediately after an injury in Centre for Burn Treatment in Siemianowice Śląskie in years 2003 - 2004 (at the age of 18 - 96 years, 66 women and 272 men). Clinical symptoms of generalized infection were found in all study subjects. The study group was divided into two subgroups: cured patients and patients who died of sepsis. The following parameters were assessed in both subgroups: type of microorganism isolated from blood, type of microorganism isolated from wound as well as occurrence of the same and different infections of blood and burn wound. positive blood cultures were found in 165 patients (48.8%), 106 (64.2%) were cured, 59 (35.8%) died. The most commonly isolated microorganisms in cured patients were Gram(+) Staphylococcus epidermidis MRSE (19.81%) and Staphylococcus aureus MRSA (18.87%). Gram(-) intestinal rods were least commonly isolated from this group. The most commonly isolated microorganisms from blood of patients who were to die, included non-fermenting Gram(-) rods Acinetobacter baumannii (35.59%) and Pseudomonas aeruginosa (22.03%). Mixed bacterial flora was found in the blood of 22.03% patients. Among patients who were to die, the same microorganisms were found in the

  7. Characterization of an organic solvent-tolerant thermostable glucoamylase from a halophilic isolate, Halolactibacillus sp. SK71 and its application in raw starch hydrolysis for bioethanol production.

    Science.gov (United States)

    Yu, Hui-Ying; Li, Xin

    2014-01-01

    A halophilic bacterium Halolactibacillus sp. SK71 producing extracellular glucoamylase was isolated from saline soil of Yuncheng Salt Lake, China. Enzyme production was strongly influenced by the salinity of growth medium with maximum in the presence of 5% NaCl. The glucoamylase was purified to homogeneity with a molecular mass of 78.5 kDa. It showed broad substrate specificity and raw starch hydrolyzing activity. Analysis of hydrolysis products from soluble starch by thin-layer chromatography revealed that glucose was the sole end-product, indicating the enzyme was a true glucoamylase. Optimal enzyme activity was found to be at 70°C, pH 8.0, and 7.5% NaCl. In addition, it was highly active and stable over broad ranges of temperature (0-100°C), pH (7.0-12.0), and NaCl concentration (0-20%), showing excellent thermostable, alkali stable, and halotolerant properties. Furthermore, it displayed high stability in the presence of hydrophobic organic solvents. The purified glucoamylase was applied for raw corn starch hydrolysis and subsequent bioethanol production using Saccharomyces cerevisiae. The yield in terms of grams of ethanol produced per gram of sugar consumed was 0.365 g/g, with 71.6% of theoretical yield from raw corn starch. This study demonstrated the feasibility of using enzymes from halophiles for further application in bioenergy production. © 2014 American Institute of Chemical Engineers.

  8. An efficient thermotolerant and halophilic biosurfactant-producing bacterium isolated from Dagang oil field for MEOR application

    Science.gov (United States)

    Wu, Langping; Richnow, Hans; Yao, Jun; Jain, Anil

    2014-05-01

    Dagang Oil field (Petro China Company Limited) is one of the most productive oil fields in China. In this study, 34 biosurfactant-producing strains were isolated and cultured from petroleum reservoir of Dagang oil field, using haemolytic assay and the qualitative oil-displacement test. On the basis of 16S rDNA analysis, the isolates were closely related to the species in genus Pseudomonas, Staphylococcus and Bacillus. One of the isolates identified as Bacillus subtilis BS2 were selected for further study. This bacterium was able to produce a type of biosurfactant with excessive foam-forming properties at 37ºC as well as at higher temperature of 55ºC. The biosurfactant produced by the strain BS2 could reduce the surface tension of the culture broth from 70.87 mN/m to 28.97 mN/m after 8 days of incubation at 37ºC and to 36.15 mN/m after 20 days of incubation at 55ºC, respectively. The biosurfactant showed stability at high temperature (up to 120ºC), a wide range of pH (2 to 12) and salt concentrations (up to 12%) offering potential for biotechnology. Fourier transform infrared (FT-IR) spectrum of extracted biosurfactant tentatively characterized the produced biosurfactant as glycolipid derivative. Elemental analysis of the biosurfactant by energy dispersive X-ray spectroscopy (EDS) reveals that the biosurfactant was anionic in nature. 15 days of biodegradation of crude oil suggested a preferential usage of n-alkane upon microbial metabolism of BS2 as a carbon substrate and consequently also for the synthesis of biosurfactants. Core flood studies for oil release indicated 9.6% of additional oil recovery over water flooding at 37ºC and 7.2% of additional oil recovery at 55 ºC. Strain BS2 was characterized as an efficient biosurfactant-producing, thermotolerant and halophillic bacterium and has the potential for application for microbial enhanced oil recovery (MEOR) through water flooding in China's oil fields even in situ as adapted to reservoir chemistry and

  9. Overexpression and purification of halophilic proteins in Haloferax volcanii

    OpenAIRE

    Allers, Thorsten

    2010-01-01

    Halophilic enzymes function optimally at high salt concentrations and are active at low water availability. Such conditions are encountered at elevated concentrations of solutes such as salts and sugars, and at high concentrations of organic solvents. However, expression in heterologous hosts such as Escherichia coli can cause problems, since halophilic proteins typically misfold and aggregate in conditions of low ionic strength. We have harnessed the sophisticated genetic tools available for...

  10. Prospects for robust biocatalysis: engineering of novel specificity in a halophilic amino acid dehydrogenase.

    Science.gov (United States)

    Munawar, Nayla; Engel, Paul C

    2013-01-01

    Heat- and solvent-tolerant enzymes from halophiles, potentially important industrially, offer a robust framework for protein engineering, but few solved halophilic structures exist to guide this. Homology modelling has guided mutations in glutamate dehydrogenase (GDH) from Halobacterium salinarum to emulate conversion of a mesophilic GDH to a methionine dehydrogenase. Replacement of K89, A163 and S367 by leucine, glycine and alanine converted halophilic GDH into a dehydrogenase accepting L-methionine, L-norleucine and L-norvaline as substrates. Over-expression in the halophilic expression host Haloferax volcanii and three-step purification gave ~98 % pure protein exhibiting maximum activity at pH 10. This enzyme also showed enhanced thermostability and organic solvent tolerance even at 70 °C, offering a biocatalyst resistant to harsh industrial environments. To our knowledge, this is the first reported amino acid specificity change engineered in a halophilic enzyme, encouraging use of mesophilic models to guide engineering of novel halophilic biocatalysts for industrial application. Calibrated gel filtration experiments show that both the mutant and the wild-type enzyme are stable hexamers.

  11. Stoichiometric and kinetic analysis of extreme halophilic Archaea on various substrates in a corrosion resistant bioreactor.

    Science.gov (United States)

    Lorantfy, Bettina; Seyer, Bernhard; Herwig, Christoph

    2014-01-25

    Extreme halophilic Archaea are extremophile species which can thrive in hypersaline environments of up to 3-5 M sodium chloride concentration. Although their ecology and physiology are widely identified on the microbiological level, little emphasis has been laid on quantitative bioprocess development with extreme halophiles. The goal of this study was to establish, on the one hand, a methodological basis for quantitative bioprocess analysis of extreme halophilic Archaea with an extreme halophilic strain as an example. Firstly, as a novel usage, a corrosion resistant bioreactor setup for extreme halophiles has been implemented. Then, paying special attention to total bioprocess quantification approaches, an indirect method for biomass quantification using on-line process signals was introduced. Subsequently, robust quantitative data evaluation methods for halophiles could be developed, providing defined and controlled cultivation conditions in the bioreactor and therefore obtaining suitable quality of on-line as well as off-line datasets. On the other hand, new physiological results of extreme halophiles in bioreactor have also been obtained based on the quantitative methodological tools. For the first time, quantitative data on stoichiometry and kinetics were collected and evaluated on different carbon sources. The results on various substrates were interpreted, with proposed metabolic mechanisms, by linking to the reported primary carbon metabolism of extreme halophilic Archaea. Moreover, results of chemostat cultures demonstrated that extreme halophilic organisms show Monod-kinetics on different sole carbon sources. A diauxic growth pattern was described on a mixture of substrates in batch cultivations. In addition, the methodologies presented here enable one to characterize the utilized strain Haloferax mediterranei (HFX) as a potential new host organism. Thus, this study offers a strong methodological basis as well as a fundamental physiological assessment for

  12. Adsorption of aflatoxin B1, zearalenone and ochratoxin A by microorganisms isolated from Kefir grains.

    Science.gov (United States)

    Taheur, Fadia Ben; Fedhila, Kais; Chaieb, Kamel; Kouidhi, Bochra; Bakhrouf, Amina; Abrunhosa, Luís

    2017-06-19

    A strategy to reduce the deleterious effects of mycotoxins is to use dietary supplements that contain microorganisms that bind mycotoxins and decrease their gastrointestinal absorption. Novel strains were isolated from a Kefir culture and assessed for their mycotoxin adsorption and biotransformation ability. The most active strains were identified using DNA sequencing, and the stability of microorganism/mycotoxin complexes was evaluated using buffer solutions to simulate the pH conditions in the gastrointestinal tract. Our results showed that the microorganism consortium of Kefir grains adsorbed 82 to 100% of aflatoxin B1 (AFB1), zearalenone (ZEA) and ochratoxin A (OTA) when cultivated in milk. The main strains that were capable of mycotoxin adsorption were identified as Lactobacillus kefiri, Kazachstania servazzii and Acetobacter syzygii. The strain L. kefiri KFLM3 was the most active, adsorbing 80 to 100% of the studied mycotoxins when cultivated in milk. Nonetheless, the strain K. servazzii KFGY7 retained more mycotoxin after the desorption experiments (65, 69 and 67% for AFB1, OTA and ZEA, respectively). These findings suggest that Kefir consumption may help to reduce gastrointestinal absorption of these mycotoxins and consequently reduce their toxic effects. The isolated strains may be of interest for the development of fermented dairy products for human consumption that have a new probiotic characteristic, the adsorption of mycotoxins. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Isolation and characterization of microorganisms and volatiles associated with Moroccan saffron during different processing treatments.

    Science.gov (United States)

    Fancello, Francesco; Petretto, Giacomo; Sanna, Maria Lina; Pintore, Giorgio; Lage, Mounira; Zara, Severino

    2018-05-20

    Saffron may be spoiled by a variety of microorganisms during cultivation, harvesting, and post harvesting. As saffron can be dried and stored in different ways, this preliminary study explored the natural microbiota present in Moroccan saffron when subjected to different drying techniques. An analysis of the carotenoid-derived volatiles present in the saffron was also carried out. The culturable microbiota of the saffron samples dried using different methods, namely in the shade (also called natural), in the sun, or in the oven, were studied using classical and molecular approaches. The effect of the drying methods on head-space chemical volatiles was also determined. Eighty-two isolates grown in the different culture media were chosen from the colonies, and genotype analysis grouped the microorganisms into 58 clusters, revealing a wide diversity. Out of the 82 isolates, 75 belonged to the Bacillaceae family. The other isolates were distributed within the Dietziaceae, Paenibacillaceae and Carnobacteriaceae families. The dominant species was Bacillus simplex, which was detected in all samples, regardless of the drying method used. Lysinibacillus macroides was dominant in the sun-dried saffron. No pathogens were isolated, but an isolate belonging to Dietzia maris, a potential human pathogenic species, was detected. The biodiversity indexes were linked to the drying method and generally decreased as the intensity of the treatment increased. The results of this preliminary work show that the different drying methods strongly influenced the microbiota and affect the saffron volatile profile. Further analysis will be needed to determine possible effects of selected microbiota on saffron volatiles. Copyright © 2018 Elsevier B.V. All rights reserved.

  14. Amyloid fibril formation in vitro from halophilic metal binding protein: Its high solubility and reversibility minimized formation of amorphous protein aggregations

    Science.gov (United States)

    Tokunaga, Yuhei; Matsumoto, Mitsuharu; Tokunaga, Masao; Arakawa, Tsutomu; Sugimoto, Yasushi

    2013-01-01

    Halophilic proteins are characterized by high net negative charges and relatively small fraction of hydrophobic amino acids, rendering them aggregation resistant. These properties are also shared by histidine-rich metal binding protein (HP) from moderate halophile, Chromohalobacter salexigens, used in this study. Here, we examined how halophilic proteins form amyloid fibrils in vitro. His-tagged HP, incubated at pH 2.0 and 58°C, readily formed amyloid fibrils, as observed by thioflavin fluorescence, CD spectra, and transmission or atomic force microscopies. Under these low-pH harsh conditions, however, His-HP was promptly hydrolyzed to smaller peptides most likely responsible for rapid formation of amyloid fibril. Three major acid-hydrolyzed peptides were isolated from fibrils and turned out to readily form fibrils. The synthetic peptides predicted to form fibrils in these peptide sequences by Waltz software also formed fibrils. Amyloid fibril was also readily formed from full-length His-HP when incubated with 10–20% 2,2,2-trifluoroethanol at pH 7.8 and 25°C without peptide bond cleavage. PMID:24038709

  15. Uptake and distribution of 137Cs and stable Cs by microorganisms isolated from mushroom substrata in the Japanese forests

    International Nuclear Information System (INIS)

    Kuwahara, Chikako; Fukumoto, Atsushi; Kato, Fumio; Sugiyama, Hideo

    2004-01-01

    The pH values of wild mushroom substrata, the influence of pH in medium on the appearance frequencies of microorganisms from mushroom substrata, and growth and Cs uptake by several microorganisms were investigated. The results showed that the pH values of 42 mushroom substrata were slightly acidic. There was no remarkable difference in the appearance frequencies of filamentous actinomycetes and planktonic bacteria at pH 5, 6 and 7, except in the samples of mushroom substrata from Mt. Fuji. The values of Cs concentration ratio (CR) for microorganisms isolated from mushroom substrata and for mushrooms were almost the same level, suggesting that those microorganisms could take up Cs in substrata and reserve Cs in their cells. (author)

  16. Cloning, characterization and analysis of cat and ben genes from the phenol degrading halophilic bacterium Halomonas organivorans.

    Directory of Open Access Journals (Sweden)

    Maria de Lourdes Moreno

    Full Text Available BACKGROUND: Extensive use of phenolic compounds in industry has resulted in the generation of saline wastewaters that produce significant environmental contamination; however, little information is available on the degradation of phenolic compounds in saline conditions. Halomonas organivorans G-16.1 (CECT 5995(T is a moderately halophilic bacterium that we isolated in a previous work from saline environments of South Spain by enrichment for growth in different pollutants, including phenolic compounds. PCR amplification with degenerate primers revealed the presence of genes encoding ring-cleaving enzymes of the β-ketoadipate pathway for aromatic catabolism in H. organivorans. FINDINGS: The gene cluster catRBCA, involved in catechol degradation, was isolated from H. organivorans. The genes catA, catB, catC and the divergently transcribed catR code for catechol 1,2-dioxygenase (1,2-CTD, cis,cis-muconate cycloisomerase, muconolactone delta-isomerase and a LysR-type transcriptional regulator, respectively. The benzoate catabolic genes (benA and benB are located flanking the cat genes. The expression of cat and ben genes by phenol and benzoic acid was shown by RT-PCR analysis. The induction of catA gene by phenol and benzoic acid was also probed by the measurement of 1,2-CTD activity in H. organivorans growth in presence of these inducers. 16S rRNA and catA gene-based phylogenies were established among different degrading bacteria showing no phylogenetic correlation between both genes. CONCLUSIONS/SIGNIFICANCE: In this work, we isolated and determined the sequence of a gene cluster from a moderately halophilic bacterium encoding ortho-pathway genes involved in the catabolic metabolism of phenol and analyzed the gene organization, constituting the first report characterizing catabolic genes involved in the degradation of phenol in moderate halophiles, providing an ideal model system to investigate the potential use of this group of extremophiles in

  17. Haloprofundus marisrubri gen. nov., sp. nov., an extremely halophilic archaeon isolated from a brine-seawater interface.

    Science.gov (United States)

    Zhang, Guishan; Gu, Jingang; Zhang, Ruifu; Rashid, Mamoon; Haroon, Mohamed Fauzi; Xun, Weibing; Ruan, Zhiyong; Dong, Xiuzhu; Stingl, Ulrich

    2017-01-01

    We isolated a Gram-stain-negative, pink-pigmented, motile, pleomorphic, extremely halophilic archaeon from the brine-seawater interface of Discovery Deep in the Saudi Arabian Red Sea. This strain, designated SB9T, was capable of growth within a wide range of temperatures and salinity, but required MgCl2. Cells lysed in distilled water, but at 7.0 % (w/v) NaCl cell lysis was prevented. The major polar lipids from strain SB9T were phosphatidylglycerol, phosphatidylglycerolphosphate methyl ester, sulfated mannosyl glucosyl diether, mannosyl glucosyl diether, an unidentified glycolipid and two unidentified phospholipids. The major respiratory quinones of strain SB9T were menaquinones MK8 (66 %) and MK8 (VIII-H2) (34 %). Analysis of the 16S rRNA gene sequence revealed that strain SB9T was closely related to species in the genera Halogranum and Haloplanus; in particular, it shared highest sequence similarity with the type strain of Halogranum rubrum (93.4 %), making it its closest known relative. The unfinished draft genome of strain SB9Twas 3 931 127 bp in size with a total G+C content of 62.53 mol% and contained 3917 ORFs, 50 tRNAs and eight rRNAs. Based on comparisons with currently available genomes, the highest average nucleotide identity value was 83 % to Halogranum salarium B-1T (GenBank accession no. GCA_000283335.1). These data indicate that this new isolate cannot be classified into any recognized genera of the family Haloferacaceae, and therefore strain SB9T is considered to be a representative of a novel species of a new genus within this family, for which the name Haloprofundus marisrubri gen. nov., sp. nov. is proposed. The type strain of Haloprofundus marisrubri is SB9T (=JCM 19565T=CGMCC 1.14959T).

  18. Microbial culturomics unravels the halophilic microbiota repertoire of table salt: description of Gracilibacillus massiliensis sp. nov.

    Directory of Open Access Journals (Sweden)

    Awa Diop

    2016-10-01

    Full Text Available Background: Microbial culturomics represents an ongoing revolution in the characterization of environmental and human microbiome. Methods: By using three media containing high salt concentration (100, 150, and 200 g/L, the halophilic microbial culturome of a commercial table salt was determined. Results: Eighteen species belonging to the Terrabacteria group were isolated including eight moderate halophilic and 10 halotolerant bacteria. Gracilibacillus massiliensis sp. nov., type strain Awa-1T (=CSUR P1441=DSM 29726, is a moderately halophilic gram-positive, non-spore-forming rod, and is motile by using a flagellum. Strain Awa-1T shows catalase activity but no oxidase activity. It is not only an aerobic bacterium but also able to grow in anaerobic and microaerophilic atmospheres. The draft genome of G. massiliensis is 4,207,226 bp long, composed of 13 scaffolds with 36.05% of G+C content. It contains 3,908 genes (3,839 protein-coding and 69 RNA genes. At least 1,983 (52% orthologous proteins were not shared with the closest phylogenetic species. Hundred twenty-six genes (3.3% were identified as ORFans. Conclusions: Microbial culturomics can dramatically improve the characterization of the food and environmental microbiota repertoire, deciphering new bacterial species and new genes. Further studies will clarify the geographic specificity and the putative role of these new microbes and their related functional genetic content in environment, health, and disease.

  19. Microbial culturomics unravels the halophilic microbiota repertoire of table salt: description of Gracilibacillus massiliensis sp. nov.

    Science.gov (United States)

    Diop, Awa; Khelaifia, Saber; Armstrong, Nicholas; Labas, Noémie; Fournier, Pierre-Edouard; Raoult, Didier; Million, Matthieu

    2016-01-01

    Microbial culturomics represents an ongoing revolution in the characterization of environmental and human microbiome. By using three media containing high salt concentration (100, 150, and 200 g/L), the halophilic microbial culturome of a commercial table salt was determined. Eighteen species belonging to the Terrabacteria group were isolated including eight moderate halophilic and 10 halotolerant bacteria. Gracilibacillus massiliensis sp. nov., type strain Awa-1 T (=CSUR P1441=DSM 29726), is a moderately halophilic gram-positive, non-spore-forming rod, and is motile by using a flagellum. Strain Awa-1 T shows catalase activity but no oxidase activity. It is not only an aerobic bacterium but also able to grow in anaerobic and microaerophilic atmospheres. The draft genome of G. massiliensis is 4,207,226 bp long, composed of 13 scaffolds with 36.05% of G+C content. It contains 3,908 genes (3,839 protein-coding and 69 RNA genes). At least 1,983 (52%) orthologous proteins were not shared with the closest phylogenetic species. Hundred twenty-six genes (3.3%) were identified as ORFans. Microbial culturomics can dramatically improve the characterization of the food and environmental microbiota repertoire, deciphering new bacterial species and new genes. Further studies will clarify the geographic specificity and the putative role of these new microbes and their related functional genetic content in environment, health, and disease.

  20. Ferric Sulfate and Proline Enhance Heavy-Metal Tolerance of Halophilic/Halotolerant Soil Microorganisms and Their Bioremediation Potential for Spilled-Oil Under Multiple Stresses

    Science.gov (United States)

    Al-Mailem, Dina M.; Eliyas, Mohamed; Radwan, Samir S.

    2018-01-01

    The aim of this study was to explore the heavy-metal resistance and hydrocarbonoclastic potential of microorganisms in a hypersaline soil. For this, hydrocarbonoclastic microorganisms were counted on a mineral medium with oil vapor as a sole carbon source in the presence of increasing concentrations of ZnSO4, HgCl2, CdSO4, PbNO3, CuSO4, and Na2HAsO4. The colony-forming units counted decreased in number from about 150 g-1 on the heavy-metal-free medium to zero units on media with 40–100 mg l-1 of HgCl2, CdSO4, PbNO3, or Na2HAsO4. On media with CuSO4 or ZnSO4 on the other hand, numbers increased first reaching maxima on media with 50 mg l-1 CuSO4 and 90 mg l-1 ZnSO4. Higher concentrations reduced the numbers, which however, still remained considerable. Pure microbial isolates in cultures tolerated 200–1600 mg l-1 of HgCl2, CdSO4, PbNO3, CuSO4, and Na2HAsO4 in the absence of crude oil. In the presence of oil vapor, the isolates tolerated much lower concentrations of the heavy metals, only 10–80 mg l-1. The addition of 10 Fe2(SO4)3 and 200 mg l-1 proline (by up to two- to threefold) enhanced the tolerance of several isolates to heavy metals, and consequently their potential for oil biodegradation in their presence. The results are useful in designing bioremediation technologies for oil spilled in hypersaline areas. PMID:29563904

  1. Polymer Film-Based Screening and Isolation of Polylactic Acid (PLA)-Degrading Microorganisms.

    Science.gov (United States)

    Kim, Mi Yeon; Kim, Changman; Moon, Jungheun; Heo, Jinhee; Jung, Sokhee P; Kim, Jung Rae

    2017-02-28

    Polylactic acid (PLA) has been highlighted as an alternative renewable polymer for the replacement of petroleum-based plastic materials, and is considered to be biodegradable. On the other hand, the biodegradation of PLA by terminal degraders, such as microorganisms, requires a lengthy period in the natural environment, and its mechanism is not completely understood. PLA biodegradation studies have been conducted using mainly undefined mixed cultures, but only a few bacterial strains have been isolated and examined. For further characterization of PLA biodegradation, in this study, the PLA-degrading bacteria from digester sludge were isolated and identified using a polymer film-based screening method. The enrichment of sludge on PLA granules was conducted with the serial transference of a subculture into fresh media for 40 days, and the attached biofilm was inoculated on a PLA film on an agar plate. 3D optical microscopy showed that the isolates physically degraded the PLA film due to bacterial degradation. 16S rRNA gene sequencing identified the microbial colonies to be Pseudomonas sp. MYK1 and Bacillus sp. MYK2. The two isolates exhibited significantly higher specific gas production rates from PLA biodegradation compared with that of the initial sludge inoculum.

  2. Radiation resistance of microorganisms on unsterilized infusion sets

    DEFF Research Database (Denmark)

    Christensen, E. Ahrensburg; Kristensen, H.; Hoborn, J.

    1991-01-01

    Three different methods were used for detecting and isolating microorganisms with high radiation resistance from the microbial contamination on infusion sets prior to sterilization. By all three methods, microorganisms with a radiation resistance high enough to be a critical factor in a steriliza......Three different methods were used for detecting and isolating microorganisms with high radiation resistance from the microbial contamination on infusion sets prior to sterilization. By all three methods, microorganisms with a radiation resistance high enough to be a critical factor...

  3. Halomonas sp. BS4, A biosurfactant producing halophilic bacterium isolated from solar salt works in India and their biomedical importance.

    Science.gov (United States)

    Donio, Mariathason Birdilla Selva; Ronica, Fernando Arul; Viji, Vijayaragavan Thanga; Velmurugan, Subramanian; Jenifer, John Selesteen Charles Adlin; Michaelbabu, Mariavincent; Dhar, Prasenjit; Citarasu, Thavasimuthu

    2013-12-01

    Halophilic bacteria were isolated from Thamaraikulam solar salt works in India. After routine biosurfactant screening by various methods, the biosurfactant producing bacteria, Halomonas sp BS4 was confirmed by 16 S rRNA sequencing. The growth optimization of Halomonas sp BS4 revealed their optimum growth at 8% NaCl and 6-8 pH in the growth medium. Further the partially purified biosurfactants were characterized by TLC, FTIR and GC-MS analysis. GC-MS results revealed that, the partial purified biosurfactants contain 1, 2-Ethanediamine N, N, N', N'-tetra, 8-Methyl-6-nonenamide, (Z)-9-octadecenamide and a fatty acid derivative. Pharmacological screening of antibacterial, antifungal, antiviral and anticancer assays revealed that, the biosurfactant extracted from Halomonas sp BS4 effectively controlled the human pathogenic bacteria and fungi an aquaculturally important virus, WSSV. The biosurfactant also suppressed the proliferation of mammary epithelial carcinoma cell by 46.77% at 2.5 μg concentration. Based on these findings, the present study concluded that, there is a possibility to develop eco-friendly antimicrobial and anticancer drugs from the extremophilic origin.

  4. Polysaccharides from Extremophilic Microorganisms

    Science.gov (United States)

    Nicolaus, B.; Moriello, V. Schiano; Lama, L.; Poli, A.; Gambacorta, A.

    2004-02-01

    Several marine thermophilic strains were analyzed for exopolysaccharide production. The screening process revealed that a significant number of thermophilic microorganisms were able to produce biopolymers, and some of them also revealed interesting chemical compositions. We have identified four new polysaccharides from thermophilic marine bacteria, with complex primary structures and with different repetitive units: a galacto-mannane type from strain number 4004 and mannane type for the other strains. The thermophilic Bacillus thermantarcticus produces two exocellular polysaccharides (EPS 1, EPS 2) that give the colonies a typical mucous character. The exopolysaccharide fraction was produced with all substrates assayed, although a higher yield 400 mg liter-1 was obtained with mannose as carbon and energy source. NMR spectra confirmed that EPS 1 was a heteropolysaccharide of which the repeating unit was constituted by four different α-D-mannoses and three different β-D-glucoses. It seems to be close to some xantan polymers. EPS 2 was a mannan. Four different α-D-mannoses were found as the repeating unit. Production and chemical studies of biopolymers produced by halophilic archaea, Haloarcula species were also reported.

  5. Microorganisms of Grape Berries

    Directory of Open Access Journals (Sweden)

    Kántor Attila

    2017-12-01

    Full Text Available Grape surface is an unstable habitat that changes greatly according to the stage of grape ripening. Different bacteria and yeasts can colonise the surface of grape berry and the diversity of microorganisms depends on the stage of ripening, pesticide application and health condition. The aim of this study was to study the microflora of the surface of grape berries. Altogether, 19 grape samples from Slovakia were collected. The spread plate method was applied and a 100 μL inoculum of each dilution (10−2, 10−3 was plated on TSA, MEA, and MRS agar for isolation of microorganisms from grapes. Proteins were extracted from cells by ethanol/formic acid extraction procedure. MALDI-TOF Mass Spectrometry was used for identification of microorganisms. In total, 11 genera of Gram-negative bacteria, 11 of Gram-positive bacteria and nine of yeasts were identified. Among 200 isolates, Gram-negative, Gram-positive bacteria and yeasts represented 11%, 27% and 62% of the total number of isolates studied. The most common genera of isolated yeasts were Hanseniaspora (37%, Metschnikowia (31%, and Rhodotorula (10%. The most frequently isolated among Gram-negative bacteria were Acinetobacter (22%, Pseudomonas (22% and Sphingomonas (13%. The most common genera of Gram-positive bacteria were Bacillus (20%, Lactobacillus (19%, Leuconostoc and Staphylococcus (11%, respectively.

  6. High-Throughput Screening for a Moderately Halophilic Phenol-Degrading Strain and Its Salt Tolerance Response

    Science.gov (United States)

    Lu, Zhi-Yan; Guo, Xiao-Jue; Li, Hui; Huang, Zhong-Zi; Lin, Kuang-Fei; Liu, Yong-Di

    2015-01-01

    A high-throughput screening system for moderately halophilic phenol-degrading bacteria from various habitats was developed to replace the conventional strain screening owing to its high efficiency. Bacterial enrichments were cultivated in 48 deep well microplates instead of shake flasks or tubes. Measurement of phenol concentrations was performed in 96-well microplates instead of using the conventional spectrophotometric method or high-performance liquid chromatography (HPLC). The high-throughput screening system was used to cultivate forty-three bacterial enrichments and gained a halophilic bacterial community E3 with the best phenol-degrading capability. Halomonas sp. strain 4-5 was isolated from the E3 community. Strain 4-5 was able to degrade more than 94% of the phenol (500 mg·L−1 starting concentration) over a range of 3%–10% NaCl. Additionally, the strain accumulated the compatible solute, ectoine, with increasing salt concentrations. PCR detection of the functional genes suggested that the largest subunit of multicomponent phenol hydroxylase (LmPH) and catechol 1,2-dioxygenase (C12O) were active in the phenol degradation process. PMID:26020478

  7. Multistage bioassociation of uranium onto an extremely halophilic archaeon revealed by a unique combination of spectroscopic and microscopic techniques.

    Science.gov (United States)

    Bader, Miriam; Müller, Katharina; Foerstendorf, Harald; Drobot, Björn; Schmidt, Matthias; Musat, Niculina; Swanson, Juliet S; Reed, Donald T; Stumpf, Thorsten; Cherkouk, Andrea

    2017-04-05

    The interactions of two extremely halophilic archaea with uranium were investigated at high ionic strength as a function of time, pH and uranium concentration. Halobacterium noricense DSM-15987 and Halobacterium sp. putatively noricense, isolated from the Waste Isolation Pilot Plant repository, were used for these investigations. The kinetics of U(VI) bioassociation with both strains showed an atypical multistage behavior, meaning that after an initial phase of U(VI) sorption, an unexpected interim period of U(VI) release was observed, followed by a slow reassociation of uranium with the cells. By applying in situ attenuated total reflection Fourier-transform infrared spectroscopy, the involvement of phosphoryl and carboxylate groups in U(VI) complexation during the first biosorption phase was shown. Differences in cell morphology and uranium localization become visible at different stages of the bioassociation process, as shown with scanning electron microscopy in combination with energy dispersive X-ray spectroscopy. Our results demonstrate for the first time that association of uranium with the extremely halophilic archaeon is a multistage process, beginning with sorption and followed by another process, probably biomineralization. Copyright © 2016. Published by Elsevier B.V.

  8. Biodegradation of glyphosate herbicide by Salinicoccus spp isolated from Qom Hoze-soltan lake, Iran

    Directory of Open Access Journals (Sweden)

    Yaser Sharifi

    2015-01-01

    Full Text Available Background: Glyphosate (N-phosphonomethyl Glycine is an organophosphorus pesticide with dangerous effects on the environment. In this study, the biodegradation of glyphosate herbicide by halophilic bacteria isolated from Qom Hoze-Soltan Lake has been investigated. Methods: After sampling and bacterial isolation, native halophilic strains grown in the presence of glyphosate at a wavelength of 660 nm and also the disappearance of the glyphosate in the plates at a wavelength of 220 nm were determined and the dominant bacteria were isolated. Biochemical, molecular (according to the 16S rRNA sequence, antibiotic, and the Minimum Inhibitory Concentration (MIC test was performed for the dominant bacteria. Analysis of the remaining glyphosate herbicide was performed by HPLC analysis after derivation with FMOC-Cl. Results: According to the results of the biochemical, antibiotic and molecular 16S rRNA tests, the native halophilic isolates with the ability to biodegrade glyphosate were gram positive cocci very similar to Salinicoccusspp. The results of HPLC showed that Salinicoccusspp is able to biodegrade glyphosate herbicide. Conclusion: The native bacteria in Qom Hoze-soltanlake, Iran can be used for biodegradation of glyphosate herbicide.

  9. ISOLATION AND IDENTIFICATION OF MICROORGANISMS DURING SPONTANEOUS FERMENTATION OF MAIZE [Isolasi dan Identifikasi Mikroorganisme pada Fermentasi Spontan Jagung

    Directory of Open Access Journals (Sweden)

    Rahmawati1,2

    2013-06-01

    Full Text Available Maize was traditionally the second most common staple food in Indonesia. Conversion to maize flour has been accomplished to improve its convenience. Traditionally, maize flour is produced by soaking the kernels in water followed by grinding. It was reported that final physicochemical characteristics of the maize flour were influenced by spontaneous fermentation which occurred during soaking. This research aimed to isolate and identify important microorganisms that grew during fermentation thus a standardized starter culture can be developed for a more controlled fermentation process. Soaking of maize grits was conducted in sterile water (grits:water=1:2, w/v in a closed container at room temperature (±28ºC for 72 hours. After 0, 4, 12, 24, 36, 48, 72 hours, water and maize grits were sampled and tested for the presence of mold, yeast, and lactic acid bacteria (LAB. Isolates obtained from the spontaneous fermentation were reinoculated into the appropriate media containing starch to observe their amylolytic activity. Individual isolate was then identified; mold by slide culture method, while yeast and LAB by biochemical rapid kits, i.e. API 20C AUX and API CH50, respectively. The number of each microorganism was plotted against time to obtain the growth curve of the microorganisms during spontaneous fermentation. The microorganisms were identified as Penicillium chrysogenum, P. citrinum, A. flavus, A. niger, Rhizopus stolonifer, R.oryzae, Fusarium oxysporum, Acremonium strictum, Candida famata, Kodamaea ohmeri, Candida krusei/incospicua, Lactobacillus plantarum 1a, Pediococcus pentosaceus, L. brevis 1, L. plantarum 1b, and L. paracasei ssp paracasei 3. Four molds and one yeast were amylolytic while none of the LAB was capable of starch hydrolysis. The growth curve suggested that the amylolitic mold and yeast grew to hydrolyze starch during the course of fermentation, while the LABs benefited from the hydrolyzed products and dominated the later

  10. PROTEOLYTIC AND FIBRINOLYTIC ACTIVITIES OF HALOPHILIC LACTIC ACID BACTERIA FROM TWO INDONESIAN FERMENTED FOODS

    Directory of Open Access Journals (Sweden)

    Asep A. Prihanto

    2013-04-01

    Full Text Available Exploration of fermented foods as sources of fibrinolytic enzymes is increased in the last decades. Terasi and Jambal roti is Indonesian traditional fermented fish products, which were famous in Java Island. Both are important products in Indonesian dishes, especially in Java. Investigation on halophilic lactic acid bacteria using MRS and M-17 agar obtained seventy four isolated strains. Their proteolytic and fibrinolytic activities were determined using skim milk agar and plasminogen-free fibrin plate. Twenty five isolates showed protease activities, while only four of them secreted fibrinolitic enzyme. The highest proteolytic and fibrinolytic activity was shown by TB1 strain, which is identified as Bacillus coagulans. The 16s rDNA is still in investigating to confirm the TB1 strain identity.

  11. Bioremediation of oil-based drill cuttings by a halophilic consortium isolated from oil-contaminated saline soil.

    Science.gov (United States)

    Rezaei Somee, Maryam; Shavandi, Mahmoud; Dastgheib, Seyed Mohammad Mehdi; Amoozegar, Mohammad Ali

    2018-05-01

    Oil-based drill cuttings are hazardous wastes containing complex hydrocarbons, heavy metals, and brine. Their remediation is a crucial step before release to the environment. In this work, we enriched a halophilic consortium, from oil-polluted saline soil, which is capable of degrading diesel as the main pollutant of oil-based drill cuttings. The degradation ability of the consortium was evaluated in microcosms using two different diluting agents (fine sand and biologically active soil). During the bioremediation process, the bacterial community dynamics of the microcosms was surveyed using PCR amplification of a fragment of 16S rRNA gene followed by denaturing gradient gel electrophoresis (DGGE). The diesel degradation rates were monitored by total petroleum hydrocarbon (TPH) measurement and the total count of heterotrophic and diesel-degrading bacteria. After 3 months, the microcosm containing fine sand and drill cuttings with the ratio of 1:1 (initial TPH of 36,000 mg/kg) showed the highest TPH removal (40%) and its dominant bacterial isolates belonged to the genera Dietzia, Arthrobacter , and Halomonas . DGGE results also confirmed the role of these genera in drill cuttings remediation. DGGE analysis of the bacterial diversity showed that Propionibacterium, Salinimicrobium, Marinobacter , and Dietzia are dominant in active soil microcosm; whereas Bacillus, Salinibacillus , and Marinobacter are abundant in sand microcosm. Our results suggest that the bioaugmentation strategy would be more successful if the diluting agent does not contain a complex microbial community.

  12. Glyphosate-Degrading Microorganisms from Industrial Activated Sludge

    OpenAIRE

    Balthazor, Terry M.; Hallas, Laurence E.

    1986-01-01

    A plating medium was developed to isolate N-phosphonomethylglycine (glyphosate)-degrading microorganisms, with glyphosate as the sole phosphorus source. Two industrial biosystems treating glyphosate wastes contained elevated microbial counts on the medium. One purified isolate metabolized glyphosate to aminomethylphosphonic acid, mineralizing this accumulating intermediate during log growth. This microorganism has been identified as a Flavobacterium species.

  13. Bioprospecting Archaea: Focus on Extreme Halophiles

    KAUST Repository

    Antunes, André

    2016-12-12

    In 1990, Woese et al. divided the Tree of Life into three separate domains: Eukarya, Bacteria, and Archaea. Archaea were originally perceived as little more than “odd bacteria” restricted to extreme environmental niches, but later discoveries challenged this assumption. Members of this domain populate a variety of unexpected environments (e.g. soils, seawater, and human bodies), and we currently witness ongoing massive expansions of the archaeal branch of the Tree of Life. Archaea are now recognized as major players in the biosphere and constitute a significant fraction of the earth’s biomass, yet they remain underexplored. An ongoing surge in exploration efforts is leading to an increase in the (a) number of isolated strains, (b) associated knowledge, and (c) utilization of Archaea in biotechnology. They are increasingly employed in fields as diverse as biocatalysis, biocomputing, bioplastic production, bioremediation, bioengineering, food, pharmaceuticals, and nutraceuticals. This chapter provides a general overview on bioprospecting Archaea, with a particular focus on extreme halophiles. We explore aspects such as diversity, ecology, screening techniques and biotechnology. Current and future trends in mining for applications are discussed.

  14. Isolation of microorganisms from red pepper powder and their radiosensitivity

    Energy Technology Data Exchange (ETDEWEB)

    Choi, E H; Kim, Y B; Lee, S R [Korea Atomic Energy Research Inst., Seoul (Republic of Korea)

    1977-01-01

    From samples of red pepper powder sold in Korea were isolated and identified 13 species of molds (Aspergillus amsteodami, Asp. chevalieri, Asp. clavatus, Asp. Flavus, Asp. janus var. effusus, Asp. oryzae, Asp. oryzae var. brevis, Asp. repens, Asp. sydowi, Asp. thomii, Asp. tubingensis, Penicillium thomii, Scopulariopsis brevicaulis) and 5 species of bacteria (Bacillus pumilus, Bac. subtilis, Micrococus luteus, M. varians, Staphylococcus aureus). Radiosensitivity of these microorganisms was examined to give D/sub 10/ values of 14-41 krad for molds, 11-24 krad for bacterial vegetative cells and 190-250 krad for bacterial spores. The red pepper powder was contaminated with 2-3x10/sup 2/ mold counts/g and 3-6x10/sup 7/ bacterial counts/g, which would be sufficiently destroyed by irradiating 200 krad r-rays.

  15. Isolation of microorganisms from red pepper powder and their radiosensitivity

    International Nuclear Information System (INIS)

    Choi, E.H.; Kim, Y.B.; Lee, S.R.

    1977-01-01

    From samples of red pepper powder sold in Korea were isolated and identified 13 species of molds (Aspergillus amsteodami, Asp. chevalieri, Asp. clavatus, Asp. Flavus, Asp. janus var. effusus, Asp. oryzae, Asp. oryzae var. brevis, Asp. repens, Asp. sydowi, Asp. thomii, Asp. tubingensis, Penicillium thomii, Scopulariopsis brevicaulis) and 5 species of bacteria (Bacillus pumilus, Bac. subtilis, Micrococus luteus, M. varians, Staphylococcus aureus). Radiosensitivity of these microorganisms was examined to give D 10 values of 14-41 krad for molds, 11-24 krad for bacterial vegetative cells and 190-250 krad for bacterial spores. The red pepper powder was contaminated with 2-3x10 2 mold counts/g and 3-6x10 7 bacterial counts/g, which would be sufficiently destroyed by irradiating 200 krad r-rays. (Author)

  16. Antimicrobial Compounds from Marine Invertebrates-Derived Microorganisms.

    Science.gov (United States)

    Liu, Juan; Jung, Jee H; Liu, Yonghong

    2016-01-01

    It is known that marine invertebrates, including sponges, tunicates, cnidaria or mollusks, host affluent and various communities of symbiotic microorganisms. The microorganisms associated with the invertebrates metabolized various biologically active compounds, which could be an important resource for the discovery and development of potentially novel drugs. In this review, the new compounds with antimicrobial activity isolated from marine invertebrate-derived microorganisms in the last decade (2004-2014) will be presented, with focus on the relevant antimicrobial activities, origin of isolation, and information of strain species. New compounds without antimicrobial activity were not revealed.

  17. Diagnostic accuracy of semi-quantitative and quantitative culture techniques for the diagnosis of catheter-related infections in newborns and molecular typing of isolated microorganisms.

    Science.gov (United States)

    Riboli, Danilo Flávio Moraes; Lyra, João César; Silva, Eliane Pessoa; Valadão, Luisa Leite; Bentlin, Maria Regina; Corrente, José Eduardo; Rugolo, Ligia Maria Suppo de Souza; da Cunha, Maria de Lourdes Ribeiro de Souza

    2014-05-22

    Catheter-related bloodstream infections (CR-BSIs) have become the most common cause of healthcare-associated bloodstream infections in neonatal intensive care units (ICUs). Microbiological evidence implicating catheters as the source of bloodstream infection is necessary to establish the diagnosis of CR-BSIs. Semi-quantitative culture is used to determine the presence of microorganisms on the external catheter surface, whereas quantitative culture also isolates microorganisms present inside the catheter. The main objective of this study was to determine the sensitivity and specificity of these two techniques for the diagnosis of CR-BSIs in newborns from a neonatal ICU. In addition, PFGE was used for similarity analysis of the microorganisms isolated from catheters and blood cultures. Semi-quantitative and quantitative methods were used for the culture of catheter tips obtained from newborns. Strains isolated from catheter tips and blood cultures which exhibited the same antimicrobial susceptibility profile were included in the study as positive cases of CR-BSI. PFGE of the microorganisms isolated from catheters and blood cultures was performed for similarity analysis and detection of clones in the ICU. A total of 584 catheter tips from 399 patients seen between November 2005 and June 2012 were analyzed. Twenty-nine cases of CR-BSI were confirmed. Coagulase-negative staphylococci (CoNS) were the most frequently isolated microorganisms, including S. epidermidis as the most prevalent species (65.5%), followed by S. haemolyticus (10.3%), yeasts (10.3%), K. pneumoniae (6.9%), S. aureus (3.4%), and E. coli (3.4%). The sensitivity of the semi-quantitative and quantitative techniques was 72.7% and 59.3%, respectively, and specificity was 95.7% and 94.4%. The diagnosis of CR-BSIs based on PFGE analysis of similarity between strains isolated from catheter tips and blood cultures showed 82.6% sensitivity and 100% specificity. The semi-quantitative culture method showed higher

  18. Comparison of the fuel oil biodegradation potential of hydrocarbon-assimilating microorganisms isolated from a temperate agricultural soil

    International Nuclear Information System (INIS)

    Chaineau, C.H.; Dupont, J.; Bury, E.; Oudot, J.; Morel, J.

    1999-01-01

    Strains of hydrocarbon-degrading microorganisms (bacteria and fungi) were isolated from an agricultural soil in France. In a field, a portion was treated with oily cuttings resulting from the drilling of an onshore well. The cuttings which were spread at the rate of 600 g HC m -2 contained 10% of fuel oil hydrocarbons (HC). Another part of the field was left untreated. Three months after HC spreading, HC adapted bacteria and fungi were isolated at different soil depths in the two plots and identified. The biodegradation potential of the isolated strains was monitored by measuring the degradation rate of total HC, saturated hydrocarbons, aromatic hydrocarbons and resins of the fuel. Bacteria of the genera Pseudomonas, Brevundimonas, Sphingomonas, Acinetobacter, Rhodococcus, Arthrobacter, Corynebacterium and fungi belonging to Aspergillus, Penicillium, Beauveria, Acremonium, Cladosporium, Fusarium, and Trichoderma were identified. The most active strains in the assimilation of saturates and aromatics were Arthrobacter sp., Sphingomonas spiritivorum, Acinetobacter baumanii, Beauveria alba and Penicillum simplicissimum. The biodegradation potential of the hydrocarbon utilizing microorganisms isolated from polluted or unpolluted soils were similar. In laboratory pure cultures, saturated HC were more degraded than aromatic HC, whereas resins were resistant to microbial attack. On an average, individual bacterial strains were more active than fungi in HC biodegradation. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  19. Biodegradation of international jet A-1 aviation fuel by microorganisms isolated from aircraft tank and joint hydrant storage systems.

    Science.gov (United States)

    Itah, A Y; Brooks, A A; Ogar, B O; Okure, A B

    2009-09-01

    Microorganisms contaminating international Jet A-1 aircraft fuel and fuel preserved in Joint Hydrant Storage Tank (JHST) were isolated, characterized and identified. The isolates were Bacillus subtillis, Bacillus megaterium, Flavobacterium oderatum, Sarcina flava, Micrococcus varians, Pseudomonas aeruginosa, Bacillus licheniformis, Bacillus cereus and Bacillus brevis. Others included Candida tropicalis, Candida albicans, Saccharomyces estuari, Saccharomyces cerevisiae, Schizosaccharomyces pombe, Aspergillus flavus, Aspergillus niger, Aspergillus fumigatus, Cladosporium resinae, Penicillium citrinum and Penicillium frequentans. The viable plate count of microorganisms in the Aircraft Tank ranged from 1.3 (+/-0.01) x 104 cfu/mL to 2.2 (+/-1.6) x 104 cfu/mL for bacteria and 102 cfu/mL to 1.68 (+/-0.32) x 103 cfu/mL for fungi. Total bacterial counts of 1.79 (+/-0.2) x 104 cfu/mL to 2.58 (+/-0.04) x 104 cfu/mL and total fungal count of 2.1 (+/-0.1) x 103 cfu/mL to 2.28 (+/-0.5) x 103 cfu/mL were obtained for JHST. Selected isolates were re-inoculated into filter sterilized aircraft fuels and biodegradation studies carried out. After 14 days incubation, Cladosporium resinae exhibited the highest degradation rate with a percentage weight loss of 66 followed by Candida albicans (60.6) while Penicillium citrinum was the least degrader with a weight loss of 41.6%. The ability of the isolates to utilize the fuel as their sole source of carbon and energy was examined and found to vary in growth profile between the isolates. The results imply that aviation fuel could be biodegraded by hydrocarbonoclastic microorganisms. To avert a possible deterioration of fuel quality during storage, fuel pipe clogging and failure, engine component damage, wing tank corrosion and aircraft disaster, efficient routine monitoring of aircraft fuel systems is advocated.

  20. Radioresistant microorganisms and food irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Ito, H [Japan Atomic Energy Research Inst., Takasaki, Gunma. Takasaki Radiation Chemistry Research Establishment

    1976-01-01

    This paper deals with Micrococcus radiodurans, Arthrobacter radiotolerance, etc., which were isolated and discovered as radioresistant microorganisms. As for the explanation of the mechanism of radioresistance of these microorganisms, the consideration that these organisms have marked repair power of the damaged DNA and have many opportunity to repair the damaged DNA because of their long fission term were cited. The relationship between the radioresistance of microorganisms and food irradiation was also mentioned.

  1. Characterization of micro-organisms isolated from dairy industry after cleaning and fogging disinfection with alkyl amine and peracetic acid.

    Science.gov (United States)

    Bore, E; Langsrud, S

    2005-01-01

    To characterize micro-organisms isolated from Norwegian dairy production plants after cleaning and fogging disinfection with alkyl amine/peracetic acid and to indicate reasons for survival. Microbial samples were collected from five dairy plants after cleaning and fogging disinfection. Isolates from two of these production plants, which used fogging with alkylamino acetate (plant A), and peracetic acid (plant B), were chosen for further characterization. The sequence of the 16S ribosomal DNA, fatty acid analysis and biochemical characteristics were used to identify isolates. Three isolates identified as Rhodococcus erythropolis, Methylobacterium rhodesianum and Rhodotorula mucilaginosa were isolated from plant A and one Sphingomonas sp. and two M. extorquens from plant B. Different patterns of resistance to seven disinfectants in a bactericidal suspension test and variable degree of attachment to stainless steel were found. The strains with higher disinfectant resistance showed lower degree of attachment than susceptible strains. The study identifies and characterizes micro-organisms present after cleaning and fogging disinfection. Both surface attachment and resistance were shown as possible reasons for the presence of the isolates after cleaning and disinfection. These results contribute to the awareness of disinfectant resistance as well as attachment as mechanisms of survival in dairy industry. It also strengthens the argument of frequent alternation of disinfectants in the food processing industry to avoid the establishment of resistant house strains.

  2. Microorganisms associated with the spoilage of avocado pear ...

    African Journals Online (AJOL)

    The microorganisms associated with the spoilage of Avocado pear, Persea americana fruits, purchased fresh from various markets in Benin City were investigated. The pour plate method was used for the isolation. A total of nine species of microorganisms were isolated and identified in this study. They comprise of seven ...

  3. Planococcus salinus sp. nov., a moderately halophilic bacterium isolated from a saline-alkali soil.

    Science.gov (United States)

    Gan, Longzhan; Zhang, Heming; Tian, Jiewei; Li, Xiaoguang; Long, Xiufeng; Zhang, Yuqin; Dai, Yumei; Tian, Yongqiang

    2018-02-01

    A novel aerobic, Gram-stain-positive, motile, moderately halophilic and coccoid bacterial strain, designated LCB217 T , was isolated from a saline-alkali soil in north-western China and identified using a polyphasic taxonomic approach. Growth occurred with 3-15 % (w/v) NaCl (optimum 3-5 %), at 10-45 °C (optimum 30 °C) and at pH 7.0-9.0 (optimum pH 9.0). Strain LCB217 T contained MK-7 and MK-8 as the predominant menaquinones and anteiso-C15 : 0, iso-C14 : 0 and iso-C16 : 0 as the major fatty acids. The polar lipids from strain LCB217 T consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine, one unidentified phospholipid, one unidentified aminophospholipid and one unidentified lipid. The peptidoglycan type was A4α (l-Lys-d-Glu). Phylogenetic analysis of the 16S rRNA gene sequence showed that strain LCB217 T belonged to the genus Planococcus and was closely related to the type strains Planococcus plakortidis AS/ASP6 (II) T (98.2 % similarity), Planococcus maitriensis S1 T (97.7 %) and Planococcus salinarum ISL-16 T (97.2 %). The G+C content of the genomic DNA was 49.4 mol%. DNA-DNA relatedness values between strain LCB217 T andPlanococcusplakortidis AS/ASP6 (II) T , Planococcusmaitriensis S1 T andPlanococcussalinarum ISL-16 T were 29.5, 38.1 and 39.5 %, respectively. On the basis of the phenotypic, phylogenetic and genomic data, strain LCB217 T represents a novel species of the genus Planococcus, for which the name Planococcus salinus sp. nov. is proposed. The type strain is LCB217 T (=CGMCC 1.15685 T =KCTC 33861 T ).

  4. Screening of cloud microorganisms isolated at the Puy de Dôme (France) station for the production of biosurfactants

    Science.gov (United States)

    Renard, Pascal; Canet, Isabelle; Sancelme, Martine; Wirgot, Nolwenn; Deguillaume, Laurent; Delort, Anne-Marie

    2016-09-01

    A total of 480 microorganisms collected from 39 clouds sampled at the Puy de Dôme station (alt. 1465 m; 45°46'19'' N, 2°57'52'' E; Massif Central, France) were isolated and identified. This unique collection was screened for biosurfactant (surfactants of microbial origin) production by measuring the surface tension (σ) of the crude extracts, comprising the supernatants of the pure cultures, using the pendant drop technique. The results showed that 41 % of the tested strains were active producers (σ biosurfactant producers (σ biosurfactant production (45biosurfactants. We observed some correlations between the chemical composition of cloud water and the presence of biosurfactant-producing microorganisms, suggesting the "biogeography" of this production. Moreover, the potential impact of the production of biosurfactants by cloud microorganisms on atmospheric processes is discussed.

  5. Selection of halophilic bacteria for biological control of tomato gray mould caused by Botrytis cinerea

    Directory of Open Access Journals (Sweden)

    Imane BERRADA

    2013-01-01

    Full Text Available In Morocco, tomato gray mould caused by Botrytis cinerea Pers: Fr. is a serious threat for postharvest storage of tomatoes. Fifteen halophilic bacteria were evaluated for their antagonistic activity against B. cinerea: 11 Gram positive strains assigned to the genera Bacillus (9, Jeotgalibacillus (1 and Planococcus (1 and four Gram negative strains assigned to the genera Salinivibrio (1, Vibrio (2 and Photobacterium (1. In in vitro screening, 12 antifungal isolates secreted diffusible compounds, hydrolytic enzymes or volatile compounds. In vivo screening of the isolates, Bacillus safensis CCMM B582 and Bacillus oceanisediminis CCMM B584 showed permanent antagonistic activity on tomato fruits, with 100% inhibition of B. cinerea after 7 days. These two strains may offer potential for biological control of tomato gray mould.

  6. Mass Spectrometry-Based Metabolomics of Agave Sap (Agave salmiana after Its Inoculation with Microorganisms Isolated from Agave Sap Concentrate Selected to Enhance Anticancer Activity

    Directory of Open Access Journals (Sweden)

    Luis M. Figueroa

    2017-11-01

    Full Text Available Saponins have been correlated with the reduction of cancer cell growth and the apoptotic effect of agave sap concentrate. Empirical observations of this artisanal Mexican food have shown that fermentation occurs after agave sap is concentrated, but little is known about the microorganisms that survive after cooking, or their effects on saponins and other metabolites. The aim of this study was to evaluate the changes in metabolites found in agave (A. salmiana sap after its fermentation with microorganisms isolated from agave sap concentrate, and demonstrate its potential use to enhance anticancer activity. Microorganisms were isolated by dilution plating and identified by 16S rRNA analysis. Isolates were used to ferment agave sap, and their corresponding butanolic extracts were compared with those that enhanced the cytotoxic activity on colon (Caco-2 and liver (Hep-G2 cancer cells. Metabolite changes were investigated by mass spectrometry-based metabolomics. Among 69 isolated microorganisms, the actinomycetes Arthrobacter globiformis and Gordonia sp. were used to analyze the metabolites, along with bioactivity changes. From the 939 ions that were mainly responsible for variation among fermented samples at 48 h, 96 h, and 192 h, four were correlated to anticancer activity. It was shown that magueyoside B, a kammogenin glycoside, was found at higher intensities in the samples fermented with Gordonia sp. that reduced Hep-G2 viability better than controls. These findings showed that microorganisms from agave sap concentrate change agave sap metabolites such as saponins. Butanolic extracts obtained after agave sap fermentation with Arthrobacter globiformis or Gordonia sp. increased the cancer cell growth inhibitory effect on colon or liver cancer cells, respectively.

  7. Adaptation to high salt concentrations in halotolerant/ halophilic fungi: a molecular perspective

    Directory of Open Access Journals (Sweden)

    Ana ePlemenitas

    2014-05-01

    Full Text Available Molecular studies of salt tolerance of eukaryotic microorganisms have until recently been limited to the baker’s yeast Saccharomyces cerevisiae and a few other moderately halotolerant yeast. Discovery of the extremely halotolerant and adaptable fungus Hortaea werneckii and the obligate halophile Wallemia ichthyophaga introduced two new model organisms into studies on the mechanisms of salt tolerance in eukaryotes. H. werneckii is unique in its adaptability to fluctuations in salt concentrations, as it can grow without NaCl as well as in the presence of up to 5 M NaCl. On the other hand, W. ichthyophaga requires at least 1.5 M NaCl for growth, but also grows in up to 5 M NaCl. Our studies have revealed the novel and intricate molecular mechanisms used by these fungi to combat high salt concentrations, which differ in many aspects between the extremely halotolerant H. werneckii and the halophilic W. ichthyophaga. Specifically, the high osmolarity glycerol signalling pathway that is important for sensing and responding to increased salt concentrations is here compared between H. werneckii and W. ichthyophaga. In both of these fungi, the key signalling components are conserved, but there are structural and regulation differences between these pathways in H. werneckii and W. ichthyophaga. We also address differences that have been revealed from analysis of their newly sequenced genomes. The most striking characteristics associated with H. werneckii are the large genetic redundancy, the expansion of genes encoding metal cation transporters, and a relatively recent whole genome duplication. In contrast, the genome of W. ichthyophaga is very compact, as only 4,884 protein-coding genes are predicted, which cover almost three quarters of the sequence. Importantly, there has been a significant increase in their hydrophobins, cell-wall proteins that have multiple cellular functions.

  8. Draft genome of Haloarcula rubripromontorii strain SL3, a novel halophilic archaeon isolated from the solar salterns of Cabo Rojo, Puerto Rico

    Directory of Open Access Journals (Sweden)

    Rubén Sánchez-Nieves

    2016-03-01

    Full Text Available The genus Haloarcula belongs to the family Halobacteriaceae which currently has 10 valid species. Here we report the draft genome sequence of strain SL3, a new species within this genus, isolated from the Solar Salterns of Cabo Rojo, Puerto Rico. Genome assembly performed using NGEN Assembler resulted in 18 contigs (N50 = 601,911 bp, the largest of which contains 1,023,775 bp. The genome consists of 3.97 MB and has a GC content of 61.97%. Like all species of Haloarcula, the genome encodes heterogeneous copies of the small subunit ribosomal RNA. In addition, the genome includes 6 rRNAs, 48 tRNAs, and 3797 protein coding sequences. Several carbohydrate-active enzymes genes were found, as well as enzymes involved in the dihydroxyacetone processing pathway which are not found in other Haloarcula species. The NCBI accession number for this genome is LIUF00000000 and the strain deposit number is CECT9001. Keywords: Halophilic archaea, Henome sequence, Puerto Rico

  9. Screening for isolation and characterisation of microorganisms and enzymes with usefull potential for degradation of celullose and hemicelluose

    Directory of Open Access Journals (Sweden)

    José Fernando Mikán Venegas

    2004-01-01

    Full Text Available A practical, applied microbiology and biotechnology model is presented for isolating and characterising micro-organisms, this being a tiny part of the immense biodiversity of tropical soils. These microbes' ability to produce depolymerases and accessory hydrolases degrading xyloglucans-pectates or glucoarabinoxylans is analysed to evaluate their potential for degrading plant material. We propose culturing micro-organisms on the cell wall as main carbon source and as hydrolitic activity inducer. The same cell walls can be used for cross-linking xylan and for rapid, low cost purification of cellulose and hemicellose degrading enzymes. A 500% xylanase purification yield was obtained in a single step with these affinity supports. Out of the 65 isolates obtained were finally selected for characterising isoenzymes for cellulase and xylanase activities. The five strains are suggested as being potentially useful in different industrial processes regarding degrading cellulose and hemicellulose. Key words: Cellulase, hemicellulase, affinity chromatography, cross-linked substrate, microbiological diversity, composting

  10. Comparison between the polypeptide profile of halophilic bacteria and salt tolerant plants.

    Science.gov (United States)

    Muñoz, G; González, C; Flores, P; Prado, B; Campos, V

    1997-12-01

    Changes in the polypeptide profile induced by salt stress in halotolerant and halophilic bacteria, isolated from the Atacama desert (northern Chile), were compared with those in the cotyledons of Prosopis chilensis (Leguminoseae) seedlings, a salt tolerant plant. SDS-PAGE analyses show the presence of four predominant polypeptides, with molecular weights around 78, 70, 60 and 44 kDa respectively, both in bacteria and in cotyledons from P. chilensis seedlings raised under salt stress conditions. Moreover, the 60 and 44 kDa polypeptides seem to be salt responsive, since their concentration increases with increasing NaCl in the growth medium. Our results suggest a common mechanism for salt tolerance in prokaryotes and in eukaryotes.

  11. Carbon monoxide as a metabolic energy source for extremely halophilic microbes: implications for microbial activity in Mars regolith.

    Science.gov (United States)

    King, Gary M

    2015-04-07

    Carbon monoxide occurs at relatively high concentrations (≥800 parts per million) in Mars' atmosphere, where it represents a potentially significant energy source that could fuel metabolism by a localized putative surface or near-surface microbiota. However, the plausibility of CO oxidation under conditions relevant for Mars in its past or at present has not been evaluated. Results from diverse terrestrial brines and saline soils provide the first documentation, to our knowledge, of active CO uptake at water potentials (-41 MPa to -117 MPa) that might occur in putative brines at recurrent slope lineae (RSL) on Mars. Results from two extremely halophilic isolates complement the field observations. Halorubrum str. BV1, isolated from the Bonneville Salt Flats, Utah (to our knowledge, the first documented extremely halophilic CO-oxidizing member of the Euryarchaeota), consumed CO in a salt-saturated medium with a water potential of -39.6 MPa; activity was reduced by only 28% relative to activity at its optimum water potential of -11 MPa. A proteobacterial isolate from hypersaline Mono Lake, California, Alkalilimnicola ehrlichii MLHE-1, also oxidized CO at low water potentials (-19 MPa), at temperatures within ranges reported for RSL, and under oxic, suboxic (0.2% oxygen), and anoxic conditions (oxygen-free with nitrate). MLHE-1 was unaffected by magnesium perchlorate or low atmospheric pressure (10 mbar). These results collectively establish the potential for microbial CO oxidation under conditions that might obtain at local scales (e.g., RSL) on contemporary Mars and at larger spatial scales earlier in Mars' history.

  12. Response surface method optimization of ectoine fermentation medium with moderate halophilic bacteria Halomonas sp. H02

    Science.gov (United States)

    Li, T. T.; Qu, A.; Yuan, X. N.; Tan, F. X.; Li, X. W.; Wang, T.; Zhang, L. H.

    2017-07-01

    Moderate halophilic bacteria are of halophilic bacteria whose suitable growth of NaCl is 5-10%. When the moderate halophilic bacteria response to high osmotic stress, the intracellular will synthesize small organic molecule compatible solutes. Ectoine, which is the major synthetic osmotic compatible solutes for moderate halophilic bacteria, can help microbial enzymes, nucleic acids and the whole cell resist to hypertonic, high temperature, freezing and other inverse environment. In order to increase the Ectoine production of Moderate halophilic bacteria Halomonas sp. H02, the Ectoine fermentation medium component was optimized by Plackett-Burman (PB) and Response Surface Methodology (RSM) based on the principle of non-complete equilibrium The results of PB experiments showed that the three main influencing factors of Moderate halophilic bacteria Halomonas sp. H02 synthesis Ectoine culture medium were C5H8NNaO4 concentration, NaCl concentration and initial pH. According to the center point of the steepest climbing experiment, the central combination design experiment was used to show that the model is consistent with the actual situation. The optimum combination of three influencing factors were C5H8NNaO4 41 g/L, NaCl 87.2 g/L and initial pH 5.9, and the predicted amount of Ectoine was 1835.8 mg/L, increased by 41.6%.

  13. Characterization of the proteasome from the extremely halophilic archaeon Haloarcula marismortui

    Directory of Open Access Journals (Sweden)

    B. Franzetti

    2002-01-01

    Full Text Available A 20S proteasome, comprising two subunits α and β, was purified from the extreme halophilic archaeon Haloarcula marismortui, which grows only in saturated salt conditions. The three-dimensional reconstruction of the H. marismortui proteasome (Hm proteasome, obtained from negatively stained electron micrographs, is virtually identical to the structure of a thermophilic proteasome filtered to the same resolution. The stability of the Hm proteasome was found to be less salt-dependent than that of other halophilic enzymes previously described. The proteolytic activity of the Hm proteasome was investigated using the malate dehydrogenase from H. marismortui (HmMalDH as a model substrate. The HmMalDH denatures when the salt concentration is decreased below 2 M. Under these conditions, the proteasome efficiently cleaves HmMalDH during its denaturation process, but the fully denatured HmMalDH is poorly degraded. These in vitro experiments show that, at low salt concentrations, the 20S proteasome from halophilic archaea eliminates a misfolded protein.

  14. Microbial quality and molecular identification of cultivable microorganisms isolated from an urban drinking water distribution system (Limassol, Cyprus).

    Science.gov (United States)

    Botsaris, George; Kanetis, Loukas; Slaný, Michal; Parpouna, Christiana; Makris, Konstantinos C

    2015-12-01

    Microorganisms can survive and multiply in aged urban drinking water distribution systems, leading to potential health risks. The objective of this work was to investigate the microbial quality of tap water and molecularly identify its predominant cultivable microorganisms. Tap water samples collected from 24 different households scattered in the urban area of Limassol, Cyprus, were microbiologically tested following standard protocols for coliforms, E. coli, Pseudomonas spp., Enterococcus spp., and total viable count at 22 and 37 °C. Molecular identification was performed on isolated predominant single colonies using 16SrRNA sequencing. Approximately 85% of the household water samples were contaminated with one or more microorganisms belonging to the genera of Pseudomonas, Corynebacterium, Agrobacterium, Staphylococcus, Bacillus, Delftia, Acinetobacter, Enterococcus, Enterobacter, and Aeromonas. However, all samples tested were free from E. coli. This is the first report in Cyprus molecularly confirming specific genera of relevant microbial communities in tap water.

  15. Phylogenetic and physiological diversity of microorganisms isolated from a deep greenland glacier ice core

    Science.gov (United States)

    Miteva, V. I.; Sheridan, P. P.; Brenchley, J. E.

    2004-01-01

    We studied a sample from the GISP 2 (Greenland Ice Sheet Project) ice core to determine the diversity and survival of microorganisms trapped in the ice at least 120,000 years ago. Previously, we examined the phylogenetic relationships among 16S ribosomal DNA (rDNA) sequences in a clone library obtained by PCR amplification from genomic DNA extracted from anaerobic enrichments. Here we report the isolation of nearly 800 aerobic organisms that were grouped by morphology and amplified rDNA restriction analysis patterns to select isolates for further study. The phylogenetic analyses of 56 representative rDNA sequences showed that the isolates belonged to four major phylogenetic groups: the high-G+C gram-positives, low-G+C gram-positives, Proteobacteria, and the Cytophaga-Flavobacterium-Bacteroides group. The most abundant and diverse isolates were within the high-G+C gram-positive cluster that had not been represented in the clone library. The Jukes-Cantor evolutionary distance matrix results suggested that at least 7 isolates represent new species within characterized genera and that 49 are different strains of known species. The isolates were further categorized based on the isolation conditions, temperature range for growth, enzyme activity, antibiotic resistance, presence of plasmids, and strain-specific genomic variations. A significant observation with implications for the development of novel and more effective cultivation methods was that preliminary incubation in anaerobic and aerobic liquid prior to plating on agar media greatly increased the recovery of CFU from the ice core sample.

  16. Purification and characterization of an extreme halothermophilic protease from a halophilic bacterium Chromohalobacter sp. TVSP101

    Directory of Open Access Journals (Sweden)

    Malashetty Vidyasagar

    2009-03-01

    Full Text Available An extreme halophilic bacterium was isolated from solar saltern samples and identified based on biochemical tests and 16S r RNA sequencing as Chromohalobacter sp. strain TVSP101. The halophilic protease was purified using ultrafiltration, ethanol precipitation, hydrophobic interaction column chromatography and gel permeation chromatography to 180 fold with 22% yield. The molecular mass of the protease determined by SDS PAGE was 66 kDa. The purified enzyme was salt dependent for its activity and stability with an optimum of 4.5 M NaCl. The optimum temperature for maximum protease activity was 75°C. The protease was optimally active at pH 8 and retained more than 80% of its activity in the range of pH 7-10. Sucrose and glycine at 10% (w/v were the most effective osmolytes, retained 100% activity in the absence of NaCl. The activity was completely inhibited by ZnCl2 (2 mM, 0.1% SDS and PMSF (1mM. The enzyme was not inhibited by 1mM of pepstatin, EDTA and PCMB. The protease was active and retained 100% it activity in 10% (v/v DMSO, DMF, ethanol and acetone.

  17. In Vitro Antioxidant, Antihemolytic, and Anticancer Activity of the Carotenoids from Halophilic Archaea.

    Science.gov (United States)

    Hou, Jing; Cui, Heng-Lin

    2018-03-01

    Halophilic archaea represent a promising natural source of carotenoids. However, little information is available about the biological effects of carotenoids from halophilic archaea. In this study, the carotenoids produced by seven halophilic archaeal strains Halogeometricum rufum, Halogeometricum limi, Haladaptatus litoreus, Haloplanus vescus, Halopelagius inordinatus, Halogranum rubrum, and Haloferax volcanii were identified by ultraviolet/visible spectroscopy, thin-layer chromatography, and high-performance liquid chromatography-tandem mass spectrometry. The C 50 carotenoids bacterioruberin and its derivatives monoanhydrobacterioruberin and bisanhydrobacterioruberin were found to be the predominant carotenoids. The antioxidant capacities of the carotenoids from these strains were significantly higher than β-carotene as determined by 1,1-diphenyl-2-picrylhydrazyl radical scavenging assay. The antihemolytic activities of these carotenoid extracts against H 2 O 2 -induced hemolysis in mouse erythrocytes were 3.9-6.3 times higher than β-carotene. A dose-dependent in vitro antiproliferative activity against HepG2 cells was observed for the extract from Hgm. limi, while that from Hpn. vescus exhibited a relatively high activity in a dose-independent manner. These results suggested that halophilic archaea could be considered as an alternative source of natural carotenoids with high antioxidant, antihemolytic, and anticancer activity.

  18. Isolation and initial characterization of the tellurite reducing moderately halophilic bacterium, Salinicoccus sp. strain QW6.

    Science.gov (United States)

    Amoozegar, Mohammad Ali; Ashengroph, Morahem; Malekzadeh, Feridon; Reza Razavi, Mohamad; Naddaf, Saied; Kabiri, Mahboubeh

    2008-01-01

    Among the 49 strains of moderately halophilic bacteria isolated from the salty environments of Iran, a Gram-positive coccus designated as strain QW6 showed high capacity in the removal of toxic oxyanions of tellurium in a wide range of culture medium factors including pH (5.5-10.5), temperature (25-45 degrees C), various salts including NaCl, KCl, and Na(2)SO(4) (0.5-4 M), selenooxyanions (2-10 mM), and at different concentrations of potassium tellurite (0.5-1 mM) under aerobic condition. Phenotypic characterization and phylogenetic analyses based on 16S rDNA sequence comparisons indicated that this strain was a member of the genus Salinicoccus. The maximum tellurite removal was exhibited in 1.5M NaCl at 35 degrees C, while the activity reduced by 53% and 47% at 25 and 45 degrees C, respectively. The optimum pH for removal activity was shown to be 7.5, with 90% and 83% reduced removal capacities at the two extreme values of 5.5 and 10, respectively. The impact of different concentrations of selenooxyanions (2-10 mM) on tellurite removal by strain QW6 was evaluated. The ability of strain QW6 in the removal of tellurite in the presence of 6mM selenite increased by 25%. The concentration of toxic potassium tellurite in the supernatant of the bacterial culture medium decreased by 99% (from 0.5 to 0.005 mM) after 6 days and the color of the medium changed to black due to the formation of less toxic elemental tellurium.

  19. Arcobacter halophilus sp nov., the first obligate halophile in the genus Arcobacter

    DEFF Research Database (Denmark)

    Donachie, S.P.; Bowman, J.P.; On, Stephen L.W.

    2005-01-01

    . Most notably, LA31B(T) was found to be an obligate halophile, a hitherto undescribed feature among recognized Arcobacter species. These data indicate that LA31B(T) should be considered to represent a novel species in the genus Arcobacter, for which the name Arcobacter halophilus sp. nov. is proposed....... This is the first obligately halophilic member of the genus. The type strain is LA31B(T) (= ATCC BAA- 102 2 T=CIP 108450(T))....

  20. Structural characteristics of alkaline phosphatase from the moderately halophilic bacterium Halomonas sp. 593

    International Nuclear Information System (INIS)

    Arai, Shigeki; Yonezawa, Yasushi; Ishibashi, Matsujiro; Matsumoto, Fumiko; Adachi, Motoyasu; Tamada, Taro; Tokunaga, Hiroko; Blaber, Michael; Tokunaga, Masao; Kuroki, Ryota

    2014-01-01

    In order to clarify the structural basis of the halophilic characteristics of an alkaline phosphatase derived from the moderate halophile Halomonas sp. 593 (HaAP), the tertiary structure of HaAP was determined to 2.1 Å resolution by X-ray crystallography. The structural properties of surface negative charge and core hydrophobicity were shown to be intermediate between those characteristic of halophiles and non-halophiles, and may explain the unique functional adaptation to a wide range of salt concentrations. Alkaline phosphatase (AP) from the moderate halophilic bacterium Halomonas sp. 593 (HaAP) catalyzes the hydrolysis of phosphomonoesters over a wide salt-concentration range (1–4 M NaCl). In order to clarify the structural basis of its halophilic characteristics and its wide-range adaptation to salt concentration, the tertiary structure of HaAP was determined by X-ray crystallography to 2.1 Å resolution. The unit cell of HaAP contained one dimer unit corresponding to the biological unit. The monomer structure of HaAP contains a domain comprised of an 11-stranded β-sheet core with 19 surrounding α-helices similar to those of APs from other species, and a unique ‘crown’ domain containing an extended ‘arm’ structure that participates in formation of a hydrophobic cluster at the entrance to the substrate-binding site. The HaAP structure also displays a unique distribution of negatively charged residues and hydrophobic residues in comparison to other known AP structures. AP from Vibrio sp. G15-21 (VAP; a slight halophile) has the highest similarity in sequence (70.0% identity) and structure (C α r.m.s.d. of 0.82 Å for the monomer) to HaAP. The surface of the HaAP dimer is substantially more acidic than that of the VAP dimer (144 exposed Asp/Glu residues versus 114, respectively), and thus may enable the solubility of HaAP under high-salt conditions. Conversely, the monomer unit of HaAP formed a substantially larger hydrophobic interior comprising 329

  1. Structural characteristics of alkaline phosphatase from the moderately halophilic bacterium Halomonas sp. 593

    Energy Technology Data Exchange (ETDEWEB)

    Arai, Shigeki; Yonezawa, Yasushi [Japan Atomic Energy Agency, 2-4 Shirakata-shirane, Tokai, Ibaraki 319-1195 (Japan); Ishibashi, Matsujiro [Faculty of Agriculture, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065 (Japan); Matsumoto, Fumiko; Adachi, Motoyasu; Tamada, Taro [Japan Atomic Energy Agency, 2-4 Shirakata-shirane, Tokai, Ibaraki 319-1195 (Japan); Tokunaga, Hiroko [Faculty of Agriculture, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065 (Japan); Blaber, Michael [Florida State University, 1115 West Call Street, Tallahassee, FL 32306-4300 (United States); Tokunaga, Masao [Faculty of Agriculture, Kagoshima University, 1-21-24 Korimoto, Kagoshima 890-0065 (Japan); Kuroki, Ryota, E-mail: kuroki.ryota@jaea.go.jp [Japan Atomic Energy Agency, 2-4 Shirakata-shirane, Tokai, Ibaraki 319-1195 (Japan)

    2014-03-01

    In order to clarify the structural basis of the halophilic characteristics of an alkaline phosphatase derived from the moderate halophile Halomonas sp. 593 (HaAP), the tertiary structure of HaAP was determined to 2.1 Å resolution by X-ray crystallography. The structural properties of surface negative charge and core hydrophobicity were shown to be intermediate between those characteristic of halophiles and non-halophiles, and may explain the unique functional adaptation to a wide range of salt concentrations. Alkaline phosphatase (AP) from the moderate halophilic bacterium Halomonas sp. 593 (HaAP) catalyzes the hydrolysis of phosphomonoesters over a wide salt-concentration range (1–4 M NaCl). In order to clarify the structural basis of its halophilic characteristics and its wide-range adaptation to salt concentration, the tertiary structure of HaAP was determined by X-ray crystallography to 2.1 Å resolution. The unit cell of HaAP contained one dimer unit corresponding to the biological unit. The monomer structure of HaAP contains a domain comprised of an 11-stranded β-sheet core with 19 surrounding α-helices similar to those of APs from other species, and a unique ‘crown’ domain containing an extended ‘arm’ structure that participates in formation of a hydrophobic cluster at the entrance to the substrate-binding site. The HaAP structure also displays a unique distribution of negatively charged residues and hydrophobic residues in comparison to other known AP structures. AP from Vibrio sp. G15-21 (VAP; a slight halophile) has the highest similarity in sequence (70.0% identity) and structure (C{sup α} r.m.s.d. of 0.82 Å for the monomer) to HaAP. The surface of the HaAP dimer is substantially more acidic than that of the VAP dimer (144 exposed Asp/Glu residues versus 114, respectively), and thus may enable the solubility of HaAP under high-salt conditions. Conversely, the monomer unit of HaAP formed a substantially larger hydrophobic interior

  2. Archaeal Viruses Multiply: Temporal Screening in a Solar Saltern

    Directory of Open Access Journals (Sweden)

    Nina S. Atanasova

    2015-04-01

    Full Text Available Hypersaline environments around the world are dominated by archaea and their viruses. To date, very little is known about these viruses and their interaction with the host strains when compared to bacterial and eukaryotic viruses. We performed the first culture-dependent temporal screening of haloarchaeal viruses and their hosts in the saltern of Samut Sakhon, Thailand, during two subsequent years (2009, 2010. Altogether we obtained 36 haloarchaeal virus isolates and 36 archaeal strains, significantly increasing the number of known archaeal virus isolates. Interestingly, the morphological distribution of our temporal isolates (head-tailed, pleomorphic, and icosahedral membrane-containing viruses was similar to the outcome of our previous spatial survey supporting the observations of a global resemblance of halophilic microorganisms and their viruses. Myoviruses represented the most abundant virus morphotype with strikingly broad host ranges. The other viral morphotypes (siphoviruses, as well as pleomorphic and icosahedral internal membrane-containing viruses were more host-specific. We also identified a group of Halorubrum strains highly susceptible to numerous different viruses (up to 26. This high virus sensitivity, the abundance of broad host range viruses, and the maintenance of infectivity over a period of one year suggest constant interplay of halophilic microorganisms and their viruses within an extreme environment.

  3. Archaeal viruses multiply: temporal screening in a solar saltern.

    Science.gov (United States)

    Atanasova, Nina S; Demina, Tatiana A; Buivydas, Andrius; Bamford, Dennis H; Oksanen, Hanna M

    2015-04-10

    Hypersaline environments around the world are dominated by archaea and their viruses. To date, very little is known about these viruses and their interaction with the host strains when compared to bacterial and eukaryotic viruses. We performed the first culture-dependent temporal screening of haloarchaeal viruses and their hosts in the saltern of Samut Sakhon, Thailand, during two subsequent years (2009, 2010). Altogether we obtained 36 haloarchaeal virus isolates and 36 archaeal strains, significantly increasing the number of known archaeal virus isolates. Interestingly, the morphological distribution of our temporal isolates (head-tailed, pleomorphic, and icosahedral membrane-containing viruses) was similar to the outcome of our previous spatial survey supporting the observations of a global resemblance of halophilic microorganisms and their viruses. Myoviruses represented the most abundant virus morphotype with strikingly broad host ranges. The other viral morphotypes (siphoviruses, as well as pleomorphic and icosahedral internal membrane-containing viruses) were more host-specific. We also identified a group of Halorubrum strains highly susceptible to numerous different viruses (up to 26). This high virus sensitivity, the abundance of broad host range viruses, and the maintenance of infectivity over a period of one year suggest constant interplay of halophilic microorganisms and their viruses within an extreme environment.

  4. Catalytic properties of thermophilic lactate dehydrogenase and halophilic malate dehydrogenase at high temperature and low water activity.

    Science.gov (United States)

    Hecht, K; Wrba, A; Jaenicke, R

    1989-07-15

    Thermophilic lactate dehydrogenases from Thermotoga maritima and Bacillus stearothermophilus are stable up to temperature limits close to the optimum growth temperature of their parent organisms. Their catalytic properties are anomalous in that Km shows a drastic increase with increasing temperature. At low temperatures, the effect levels off. Extreme halophilic malate dehydrogenase from Halobacterium marismortui exhibits a similar anomaly. Increasing salt concentration (NaCl) leads to an optimum curve for Km, oxaloacctate while Km, NADH remains constant. Previous claims that the activity of halophilic malate dehydrogenase shows a maximum at 1.25 M NaCl are caused by limiting substrate concentration; at substrate saturation, specific activity of halophilic malate dehydrogenase reaches a constant value at ionic strengths I greater than or equal to 1 M. Non-halophilic (mitochondrial) malate dehydrogenase shows Km characteristics similar to those observed for the halophilic enzyme. The drastic decrease in specific activity of the mitochondrial enzyme at elevated salt concentrations is caused by the salt-induced increase in rigidity of the enzyme, rather than gross structural changes.

  5. Degradation of 14C-parathion 'in vitro' by microorganisms isolated from a gley humic soil

    International Nuclear Information System (INIS)

    Andrea, M.M. de; Ruegg, E.F.

    1982-01-01

    It was determined 'in vitro' the degradation of Parathion by a bacterium and a fungus isolated from a sample of Gley Humic soil previously treated with repeated applications of the insecticide. In a qualitative colorimetric assay hydrolisis of parathion to p-nitrophenol just the bacterium gave a positive answer. In quantitative assays of 14 C-parathion degradation in culture media containing both microorganisms, organic solvents extractions resulted in organic and aqueous phases, which were analysed by liquid scintillation counting and thin-layer chromatography. In a mineral salts medium plus buffer, the bacterium and the fungus behaved differently from the control, because part of the 14 C-insecticide was metabolized to, at least, one metabolite and besides, the microorganisms presented smaller percentages of total recovery. The largest percentage of the radio carbon recovery from the extracts of the medium containing the fungus plus extract of yeast, was obtained from the aqueous phase and the existence of other metabolite was demonstrated by chromatograms of the organic phase. (Author) [pt

  6. Accompaniment of the biomass growth and synthesis of biosurfactants by microorganism isolated in oil wells; Acompanhamento do crescimento da biomassa e sintese de biosurfactantes por microorganismos isolados de pocos de petroleo

    Energy Technology Data Exchange (ETDEWEB)

    Lobato, Ana Katerine de Carvalho Lima; Araujo, Manuelle Meike Silva de [Rio Grande do Norte Univ., Natal, RN (Brazil). Programa de Pos-graduacao em Engenharia Quimica]. E-mail: manuelle@eq.ufrn.br; Macedo, Gorete Ribeiro de [Rio Grande do Norte Univ., Natal, RN (Brazil). Dept. de Engenharia Quimica

    2003-07-01

    Biosurfactants are structurally diversified groups of active surface molecules synthesized by microorganisms as bacteria and fungi, cultivated in several carbon sources such as sucrose and hydrocarbons. These molecules, composed by a part hydrophilic and other hydrophobic one, they act preferentially in the interface among the flowing phases with different polarities linking interfaces oil/water or water/oil reducing the superficial tensions and interfacial among these phases. They have been used in environmental applications, such as bioremediation of soils, treatment of contaminated water fountains and in cleaning process of tanks and equipment. Oil reservoirs present conditions where some microorganisms can grow. These microorganisms when isolated and cultivated at laboratory can be characterized with relation to surfactants production. In this work, microorganisms were isolated of oil wells and the biosurfactants producers were selected, among the isolated ones, to form a culture bank with potential application in environmental pollution treatment and advanced oil recovery. A microorganism stump of the developed bank was cultivated in sucrose and hydrocarbon medium and the biosurfactant production was evaluated by superficial tension measurement. The microorganism biomass production was evaluated by optical density using a spectrophotometer and the substratum consumption by Dns method. (author)

  7. First characterization of extremely halophilic 2-deoxy-D-ribose-5-phosphate aldolase.

    Science.gov (United States)

    Ohshida, Tatsuya; Hayashi, Junji; Satomura, Takenori; Kawakami, Ryushi; Ohshima, Toshihisa; Sakuraba, Haruhiko

    2016-10-01

    2-Deoxy-d-ribose-5-phosphate aldolase (DERA) catalyzes the aldol reaction between two aldehydes and is thought to be a potential biocatalyst for the production of a variety of stereo-specific materials. A gene encoding DERA from the extreme halophilic archaeon, Haloarcula japonica, was overexpressed in Escherichia coli. The gene product was successfully purified, using procedures based on the protein's halophilicity, and characterized. The expressed enzyme was stable in a buffer containing 2 M NaCl and exhibited high thermostability, retaining more than 90% of its activity after heating at 70 °C for 10 min. The enzyme was also tolerant to high concentrations of organic solvents, such as acetonitrile and dimethylsulfoxide. Moreover, H. japonica DERA was highly resistant to a high concentration of acetaldehyde and retained about 35% of its initial activity after 5-h' exposure to 300 mM acetaldehyde at 25 °C, the conditions under which E. coli DERA is completely inactivated. The enzyme exhibited much higher activity at 25 °C than the previously characterized hyperthermophilic DERAs (Sakuraba et al., 2007). Our results suggest that the extremely halophilic DERA has high potential to serve as a biocatalyst in organic syntheses. This is the first description of the biochemical characterization of a halophilic DERA. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. Haloplanus salinarum sp. nov., an extremely halophilic archaeon isolated from a solar saltern.

    Science.gov (United States)

    Hwang, Han-Bit; Kim, Ye-Eun; Koh, Hyeon-Woo; Song, Hye Seon; Roh, Seong Woon; Kim, So-Jeong; Nam, Seung Won; Park, Soo-Je

    2017-11-01

    An extremely halophilic archaeal strain SP28 T was isolated from the Gomso solar saltern, Republic of Korea. Cells of the new strain SP28 T were pleomorphic and Gram stain negative, and produced red-pigmented colonies. These grew in medium with 2.5-4.5 M NaCl (optimum 3.1 M) and 0.05-0.5 M MgCl2 (optimum 0.1 M), at 25-50 °C (optimum 37 °C) and at a pH of 6.5-8.5 (optimum pH 8.0). Mg 2+ was required for growth. A concentration of at least 2 M NaCl was required to prevent cell lysis. Polar lipids included phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate and one glycolipid chromatographically identical to sulfated mannosyl glucosyl diether. 16S rRNA and rpoB' gene sequence analyses showed that strain SP28 T is closely related to Haloplanus ruber R35 T (97.3 and 94.1 %, 16S rRNA and rpoB' gene sequence similarity, respectively), Haloplanus litoreus GX21 T (97.0 and 92.1 %), Haloplanus salinus YGH66 T (96.0 and 91.9 %), Haloplanus vescus RO5-8 T (95.9 and 90.9 %), Haloplanus aerogenes TBN37 T (95.6 and 90.3 %) and Haloplanus natans RE-101 T (95.3 and 89.8 %). The DNA G+C content of the novel strain SP28 T was 66.2 mol%, which is slightly higher than that of Hpn.litoreus GX21 T (65.8 mol%) and Hpn.ruber R35 T (66.0 mol%). DNA-DNA hybridization values betweenHpn.ruber R35 T and strain SP28 T and between Hpn.litoreus GX21 T and strain SP28 T were about 24.8 and 20.7 %, respectively. We conclude that strain SP28 T represents a novel species of the genus Haloplanus and propose the name Haloplanus salinarum sp. nov. The type strain is SP28 T (=JCM 31424 T =KCCM 43210 T ).

  9. Bioemulsan Production by Iranian Oil Reservoirs Microorganisms

    Directory of Open Access Journals (Sweden)

    A Amiriyan, M Mazaheri Assadi, VA Saggadian, A Noohi

    2004-10-01

    Full Text Available The biosurfactants are believed to be surface active components that are shed into the surrounding medium during the growth of the microorganisms. The oil degrading microorganism Acinetobacter calcoaceticus RAG-1 produces a poly-anionic biosurfactant, hetero-polysaccharide bioemulsifier termed as emulsan which forms and stabilizes oil-water emulsions with a variety of hydrophobic substrates. In the present paper results of the possibility of biosurfactant (Emulsan production by microorganisms isolated from Iranian oil reservoirs is presented. Fourthy three gram negative and gram positive, non fermentative, rod bacilli and coccobacilli shaped baceria were isolated from the oil wells of Bibi Hakimeh, Siri, Maroon, Ilam , East Paydar and West Paydar. Out of the isolated strains, 39 bacterial strains showed beta haemolytic activity, further screening revealed the emulsifying activity and surface tension. 11 out of 43 tested emulsifiers were identified as possible biosurfactant producers and two isolates produced large surface tension reduction, indicating the high probability of biosurfactant production. Further investigation revealed that, two gram negative, oxidase negative, aerobic and coccoid rods isolates were the best producers and hence designated as IL-1, PAY-4. Whole culture broth of isolates reduced surface tension from 68 mN /m to 30 and 29.1mN/m, respectively, and were stable during exposure to high salinity (10%NaCl and elevated temperatures(120C for 15 min .

  10. Actinide Biocolloid Formation in Brine by Halophilic Bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Gillow, J.B.; Francis, A.J.; Dodge, C.J.; Harris, R.; Beveridge, T.J.; Brady, P.V.; Papenguth, H.W.

    1999-07-28

    We examined the ability of a halophilic bacterium (WFP 1A) isolated from the Waste Isolation Pilot Plant (WIPP) site to accumulate uranium in order to determine the potential for biocolloid facilitated actinide transport. The bacterial cell Surface functional groups involved in the complexation of the actinide were determined by titration. Uranium, added as uranyl nitrate, was removed from solution at pH 5 by cells but at pH 7 and 9 very little uranium was removed due to its limited volubility. Although present as soluble species, uranyl citrate at pH 5, 7, and 9, and uranyl carbonate at pH 9 were not removed by the bacterium because they were not bioavailable due to their neutral or negative charge. Addition of uranyl EDTA to brine at pH 5, 7, and 9 resulted in the immediate precipitation of U. Transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS) analysis revealed that uranium was not only associated with the cell surface but also accumulated intracellulary as uranium-enriched granules. Extended X-ray absorption fine structure (EXAFS) analysis, of the bacterial cells indicated the bulk sample contained more than one uranium phase. Nevertheless these results show the potential for the formation of actinide bearing bacterial biocolloids that are strictly regulated by the speciation and bioavailability of the actinide.

  11. Actinide biocolloid formation in brine by halophilic bacteria

    International Nuclear Information System (INIS)

    Gillow, J.B.; Francis, A.J.; Dodge, C.J.; Harris, R.; Beveridge, T.J.; Brady, P.B.; Papenguth, H.W.

    1998-01-01

    The authors examined the ability of a halophilic bacterium (WIPP 1A) isolated from the Waste Isolation Pilot Plant (WIPP) site to accumulate uranium in order to determine the potential for biocolloid facilitated actinide transport. The bacterial cell surface functional groups involved in the complexation of the actinide were determined by titration. Uranium, added as uranyl nitrate, was removed from solution at pH 5 by cells but at pH 7 and 9 very little uranium was removed due to its limited solubility. Although present as soluble species, uranyl citrate at pH 5, 7, and 9, and uranyl carbonate at pH 9 were not removed by the bacterium because they were not bioavailable due to their neutral or negative charge. Addition of uranyl EDTA to brine at pH 5, 7, and 9 resulted in the immediate precipitation of U. Transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS) analysis revealed that uranium was not only associated with the cell surface but also accumulated intracellularly as uranium-enriched granules. Extended X-ray absorption fine structure (EXAFS) analysis of the bacterial cells indicated the bulk sample contained more than one uranium phase. Nevertheless these results show the potential for the formation of actinide bearing bacterial biocolloids that are strictly regulated by the speciation and bioavailability of the actinide

  12. Actinide biocolloid formation in brine by halophilic bacteria

    International Nuclear Information System (INIS)

    Gillow, J.B.; Francis, A.J.; Dodge, C.J.; Harris, R.; Beveridge, T.J.; Brady, P.V.; Papenguth, H.W.

    1999-01-01

    The authors examined the ability of a halophilic bacterium (WIPP 1A) isolated from the Waste Isolation Pilot Plant (WIPP) site to accumulate uranium in order to determine the potential for biocolloid facilitated actinide transport. The bacterial cell surface functional groups involved in the complexation of the actinide were determined by titration. Uranium, added as uranyl nitrate, was removed from solution at pH 5 by cells but at pH 7 and 9 very little uranium was removed due to its limited solubility. Although present as soluble species, uranyl citrate at pH 5, 7, and 9, and uranyl carbonate at pH 9 were not removed by the bacterium because they were not bioavailable due to their neutral or negative charge. Addition of uranyl EDTA to brine at pH 5, 7, and 9 resulted in the immediate precipitation of U. Transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS) analysis revealed that uranium was not only associated with the cell surface but also accumulated intracellularly as uranium-enriched granules. Extended X-ray absorption fine structure (EXAFS) analysis of the bacterial cells indicated the bulk sample contained more than one uranium phase. Nevertheless these results show the potential for the formation of actinide bearing bacterial biocolloids that are strictly regulated by the speciation and bioavailability of the actinide

  13. Actinide Biocolloid Formation in Brine by Halophilic Bacteria

    International Nuclear Information System (INIS)

    Gillow, J.B.; Francis, A.J.; Dodge, C.J.; Harris, R.; Beveridge, T.J.; Brady, P.V.; Papenguth, H.W.

    1999-01-01

    We examined the ability of a halophilic bacterium (WFP 1A) isolated from the Waste Isolation Pilot Plant (WIPP) site to accumulate uranium in order to determine the potential for biocolloid facilitated actinide transport. The bacterial cell Surface functional groups involved in the complexation of the actinide were determined by titration. Uranium, added as uranyl nitrate, was removed from solution at pH 5 by cells but at pH 7 and 9 very little uranium was removed due to its limited volubility. Although present as soluble species, uranyl citrate at pH 5, 7, and 9, and uranyl carbonate at pH 9 were not removed by the bacterium because they were not bioavailable due to their neutral or negative charge. Addition of uranyl EDTA to brine at pH 5, 7, and 9 resulted in the immediate precipitation of U. Transmission electron microscopy (TEM) and energy dispersive X-ray spectroscopy (EDS) analysis revealed that uranium was not only associated with the cell surface but also accumulated intracellulary as uranium-enriched granules. Extended X-ray absorption fine structure (EXAFS) analysis, of the bacterial cells indicated the bulk sample contained more than one uranium phase. Nevertheless these results show the potential for the formation of actinide bearing bacterial biocolloids that are strictly regulated by the speciation and bioavailability of the actinide

  14. Bipyrimidine Signatures as a Photoprotective Genome Strategy in G + C-rich Halophilic Archaea.

    Science.gov (United States)

    Jones, Daniel L; Baxter, Bonnie K

    2016-09-02

    Halophilic archaea experience high levels of ultraviolet (UV) light in their environments and demonstrate resistance to UV irradiation. DNA repair systems and carotenoids provide UV protection but do not account for the high resistance observed. Herein, we consider genomic signatures as an additional photoprotective strategy. The predominant forms of UV-induced DNA damage are cyclobutane pyrimidine dimers, most notoriously thymine dimers (T^Ts), which form at adjacent Ts. We tested whether the high G + C content seen in halophilic archaea serves a photoprotective function through limiting T nucleotides, and thus T^T lesions. However, this speculation overlooks the other bipyrimidine sequences, all of which capable of forming photolesions to varying degrees. Therefore, we designed a program to determine the frequencies of the four bipyrimidine pairs (5' to 3': TT, TC, CT, and CC) within genomes of halophilic archaea and four other randomized sample groups for comparison. The outputs for each sampled genome were weighted by the intrinsic photoreactivities of each dinucleotide pair. Statistical methods were employed to investigate intergroup differences. Our findings indicate that the UV-resistance seen in halophilic archaea can be attributed in part to a genomic strategy: high G + C content and the resulting bipyrimidine signature reduces the genomic photoreactivity.

  15. Role of Microorganisms in the Removal of Radionuclides from Soil

    International Nuclear Information System (INIS)

    Bashandy, A.S.

    2007-01-01

    Resistance to radio nuclides and their accumulation by bacteria is a wide spread phenomenon that can be explored for the improvement of the environment. Metal resistant bacteria have developed very efficient and varying mechanisms for tolerating high levels of. toxic metals and thus hold potential for controlling heavy metal pollution. This property has been successfully applied for metal removal from soil. A total of 59 microorganisms were isolated from 5 locations in Sinai Desert. The microorganisms were examined for resistance to strontium, cobalt and cesium by spot technique on two kinds of media containing metals, Nutrient agar and King B agar. The resistant microorganisms were identified morphologically by Gram stain. The microorganisms were resistant to Sr and Cs at concentrations up to 200 mg/I and while Co proved to be toxic at a concentration of 100 mg/ I. The mechanisms of metal resistance to high concentrations were studied. Evidence show that the isolated microorganisms can uptake high concentrations of the studied elements. The results also, indicated that no binding proteins are released in the environment of the studied isolate

  16. Physiologically anaerobic microorganisms of the deep subsurface

    Energy Technology Data Exchange (ETDEWEB)

    Stevens, S.E. Jr.; Chung, K.T.

    1991-06-01

    This study seeks to determine numbers, diversity, and morphology of anaerobic microorganisms in 15 samples of subsurface material from the Idaho National Engineering Laboratory, in 18 samples from the Hanford Reservation and in 1 rock sample from the Nevada Test Site; set up long term experiments on the chemical activities of anaerobic microorganisms based on these same samples; work to improve methods for the micro-scale determination of in situ anaerobic microbial activity;and to begin to isolate anaerobes from these samples into axenic culture with identification of the axenic isolates.

  17. Structural evidence for solvent-stabilisation by aspartic acid as a mechanism for halophilic protein stability in high salt concentrations.

    Science.gov (United States)

    Lenton, Samuel; Walsh, Danielle L; Rhys, Natasha H; Soper, Alan K; Dougan, Lorna

    2016-07-21

    Halophilic organisms have adapted to survive in high salt environments, where mesophilic organisms would perish. One of the biggest challenges faced by halophilic proteins is the ability to maintain both the structure and function at molar concentrations of salt. A distinct adaptation of halophilic proteins, compared to mesophilic homologues, is the abundance of aspartic acid on the protein surface. Mutagenesis and crystallographic studies of halophilic proteins suggest an important role for solvent interactions with the surface aspartic acid residues. This interaction, between the regions of the acidic protein surface and the solvent, is thought to maintain a hydration layer around the protein at molar salt concentrations thereby allowing halophilic proteins to retain their functional state. Here we present neutron diffraction data of the monomeric zwitterionic form of aspartic acid solutions at physiological pH in 0.25 M and 2.5 M concentration of potassium chloride, to mimic mesophilic and halophilic-like environmental conditions. We have used isotopic substitution in combination with empirical potential structure refinement to extract atomic-scale information from the data. Our study provides structural insights that support the hypothesis that carboxyl groups on acidic residues bind water more tightly under high salt conditions, in support of the residue-ion interaction model of halophilic protein stabilisation. Furthermore our data show that in the presence of high salt the self-association between the zwitterionic form of aspartic acid molecules is reduced, suggesting a possible mechanism through which protein aggregation is prevented.

  18. Extreme Halophiles and Carbon Monoxide: Looking Through Windows at Earth's Past and Towards a Future on Mars

    Science.gov (United States)

    King, G.

    2015-12-01

    Carbon monoxide, which is ubiquitous on Earth, is the 2nd most abundant molecule in the universe. Members of the domain Bacteria have long been known to oxidize it, and activities of CO oxidizers in soils have been known for several decades to contribute to tropospheric CO regulation. Nonetheless, the diversity of CO oxidizers and their evolutionary history remain largely unknown. A molybdenum-dependent dehydrogenase (Mo-CODH) couples CO oxidation by most terrestrial and marine bacteria to either O2 or nitrate. Molybdenum dependence, the requirement for O2 and previous phylogenetic inferences have all supported a relatively late evolution for "aerobic" CO oxidation, presumably after the Great Oxidation Event (GOE) about 2.3 Gya. Although conundrums remain, recent discoveries suggest that Mo-CODH might have evolved before the GOE, and prior to the Bacteria-Archaea split. New phylogenetic analyses incorporating sequences from extremely halophilic CO-oxidizing Euryarchaeota isolated from salterns in the Atacama Desert, brines on Hawai`i and from the Bonneville Salt Flat suggest that Mo-CODH was present in an ancestor shared by Bacteria and Archaea. This observation is consistent with results of phylogenetic histories of genes involved in Mo-cofactor synthesis, and findings by others that Mo-nitrogenase was likely active > 3 Gya. Thus, analyses of Mo-dependent CO oxidizers provide a window on the past by raising questions about the availability of Mo and non-O2 electron acceptors. Extremely halophilic CO oxidizers also provide insights relevant for understanding the potential for extraterrestrial life. CO likely occurred at high concentrations in Mars' early atmosphere, and it occurs presently at about 800 ppm. At such high concentrations, CO represents one of the most abundant energy sources available for near-surface regolith. However, use of CO by an extant or transplanted Mars microbiota would require tolerance of low water potentials and high salt concentrations

  19. Secondary metabolites from marine microorganisms.

    Science.gov (United States)

    Kelecom, Alphonse

    2002-03-01

    After 40 years of intensive research, chemistry of marine natural products has become a mature field. Since 1995, there are signals of decreased interest in the search of new metabolites from traditional sources such as macroalgae and octocorals, and the number of annual reports on marine sponges stabilized. On the contrary, metabolites from microorganisms is a rapidly growing field, due, at least in part, to the suspicion that a number of metabolites obtained from algae and invertebrates may be produced by associated microorganisms. Studies are concerned with bacteria and fungi, isolated from seawater, sediments, algae, fish and mainly from marine invertebrates such as sponges, mollusks, tunicates, coelenterates and crustaceans. Although it is still to early to define tendencies, it may be stated that the metabolites from microorganisms are in most cases quite different from those produced by the invertebrate hosts. Nitrogenated metabolites predominate over acetate derivatives, and terpenes are uncommon. Among the latter, sesquiterpenes, diterpenes and carotenes have been isolated; among nitrogenated metabolites, amides, cyclic peptides and indole alkaloids predominate.

  20. Secondary metabolites from marine microorganisms

    Directory of Open Access Journals (Sweden)

    KELECOM ALPHONSE

    2002-01-01

    Full Text Available After 40 years of intensive research, chemistry of marine natural products has become a mature field. Since 1995, there are signals of decreased interest in the search of new metabolites from traditional sources such as macroalgae and octocorals, and the number of annual reports on marine sponges stabilized. On the contrary, metabolites from microorganisms is a rapidly growing field, due, at least in part, to the suspicion that a number of metabolites obtained from algae and invertebrates may be produced by associated microorganisms. Studies are concerned with bacteria and fungi, isolated from seawater, sediments, algae, fish and mainly from marine invertebrates such as sponges, mollusks, tunicates, coelenterates and crustaceans. Although it is still to early to define tendencies, it may be stated that the metabolites from microorganisms are in most cases quite different from those produced by the invertebrate hosts. Nitrogenated metabolites predominate over acetate derivatives, and terpenes are uncommon. Among the latter, sesquiterpenes, diterpenes and carotenes have been isolated; among nitrogenated metabolites, amides, cyclic peptides and indole alkaloids predominate.

  1. Sediminibacillus massiliensis sp. nov., a moderately halophilic, Gram-positive bacterium isolated from a stool sample of a young Senegalese man.

    Science.gov (United States)

    Senghor, Bruno; Bassène, Hubert; Khelaifia, Saber; Robert, Catherine; Fournier, Pierre-Edouard; Ruimy, Raymond; Sokhna, Cheikh; Raoult, Didier; Lagier, Jean-Christophe

    2018-07-01

    A Gram-positive, moderately halophilic bacterium, referred to as strain Marseille-P3518 T , was isolated from a stool sample with 2% NaCl concentration from a healthy 15-year-old male living in Dielmo, a village in Senegal. Cells are aerobic, rod-shaped and motile and display endospore formation. Strain Marseille-P3518 T can grow in a medium with 0-20% (w/v) sodium chloride (optimally at 5-7.5% w/v). The major fatty acids were 12-methyl-tetradecanoic acid (45.8%), 13-methyl-tetradecanoic acid (26.9%) and 12-methyl-tridecanoic acid (12.8%). The genome is 4,347,479 bp long with 42.1% G+C content. It contains 4282 protein-coding and 107 RNA genes. Phylogenetic analysis based on 16S rRNA gene sequence comparisons showed that strain Marseille-P3518 T is a member of the Bacillaceae family and is closely related to Sediminibacillus albus (97.4% gene sequence similarity). Strain Marseille-P3518 T was clearly differentiated from its phylogenetic neighbors on the basis of phenotypic and genotypic features. Strain Marseille-P3518 T is, therefore, considered to be a novel representative of the genus Sediminibacillus, for which the name Sediminibacillus massiliensis sp. nov. is proposed, and the type strain is Marseille-P3518 T (CSUR P3518T, DSM69894).

  2. The Structure of the Lipid A from the Halophilic Bacterium Spiribacter salinus M19-40T

    Directory of Open Access Journals (Sweden)

    Clara Barrau

    2018-04-01

    Full Text Available The study of the adaptation mechanisms that allow microorganisms to live and proliferate in an extreme habitat is a growing research field. Directly exposed to the external environment, lipopolysaccharides (LPS from Gram-negative bacteria are of great appeal as they can present particular structural features that may aid the understanding of the adaptation processes. Moreover, through being involved in modulating the mammalian immune system response in a structure-dependent fashion, the elucidation of the LPS structure can also be seen as a fundamental step from a biomedical point of view. In this paper, the lipid A structure of the LPS from Spiribacter salinus M19-40T, a halophilic gamma-proteobacteria, was characterized through chemical analyses and matrix-assisted laser desorption ionization (MALDI mass spectrometry. This revealed a mixture of mono- and bisphosphorylated penta- to tri-acylated species with the uncommon 2 + 3 symmetry and bearing an unusual 3-oxotetradecaonic acid.

  3. First isolation of microorganisms from the gut diverticulum of Aedes aegypti (Diptera: Culicidae: new perspectives for an insect-bacteria association

    Directory of Open Access Journals (Sweden)

    Desiely Silva Gusmão

    2007-12-01

    Full Text Available We show for the first time that the ventral diverticulum of the mosquito gut (impermeable sugar storage organ harbors microorganisms. The gut diverticulum from newly emerged and non-fed Aedes aegypti was dissected under aseptic conditions, homogenized and plated on BHI medium. Microbial isolates were identified by sequencing of 16S rDNA for bacteria and 28S rDNA for yeast. A direct DNA extraction from Ae. aegypti gut diverticulum was also performed. The bacterial isolates were: Bacillus sp., Bacillus subtilis and Serratia sp. The latter was the predominant bacteria found in our isolations. The yeast species identified was Pichia caribbica.

  4. The effects of salinity on nitrification using halophilic nitrifiers in a Sequencing Batch Reactor treating hypersaline wastewater.

    Science.gov (United States)

    Cui, You-Wei; Zhang, Hong-Yu; Ding, Jie-Ran; Peng, Yong-Zhen

    2016-04-25

    With annual increases in the generation and use of saline wastewater, the need to avoid environmental problems such as eutrophication is critical. A previous study identified ways to start up a halophilic sludge domesticated from estuarine sediments to remove nitrogen from wastewater with a salinity of 30 g/L. This investigation expands that work to explore the impact of salinity on nitrogen removal. This study demonstrated that the mixed halophilic consortia removed nitrogen from wastewater with a salinity of 30-85 g/L. A kinetic analysis showed that halophilic nitrifiers selected based on hypersalinity were characterized by low Ks, μmax and specific ammonium oxidization rates. This explains the decrease in ammonium removal efficiency in the high salinity operational phases. Salinity inhibited ammonia oxidizing bacteria (AOB) activity, as well as the number of dominant AOB, but did not significantly affect the AOB dominant species. Three most dominant AOB lineages in the halophilic sludge were Nitrosomonas marina, Nitrosomonas europaea, and Nitrosococcus mobilis. Nitrosomonas europaea and Nitrosococcus mobilis were mainly affected by salinity, while nitrite accumulation and ammonia loading played the key role in determining the abundance of Nitrosococcus mobilis and Nitrosococcus europaea. The study contributes insights about shifts in halophilic nitrifying bacterial populations.

  5. [Ants as carriers of microorganisms in hospital environments].

    Science.gov (United States)

    Pereira, Rogério Dos Santos; Ueno, Mariko

    2008-01-01

    Concern exists regarding the real possibility of public health threats caused by pathogenic agents that are carried by urban ants. The present study had the objective of isolating and identifying the microorganisms that are associated with ants in hospital environments. One hundred and twenty-five ants of the same species were collected from different units of a university hospital. Each ant was collected using a swab soaked with physiological solution and was transferred to a tube containing brain heart infusion broth and incubated at 35 degrees C for 24 hours. From each tube, with growth, inoculations were made into specific culturing media, to isolate any microorganisms. The ants presented a high capacity for carrying microorganism groups: spore-producing Gram-positive bacilli 63.5%, Gram-negative bacilli 6.3%, Gram-positive cocci 23.1%, filamentous fungi 6.7% and yeast 0.5%. Thus, it can be inferred that ants may be one of the agents responsible for disseminating microorganisms in hospital environments.

  6. Effect of probiotic microorganisms isolated from Hypostomus plecostomus in Oreochromis sp juveniles

    Directory of Open Access Journals (Sweden)

    Yuri Vela-Gutiérrez

    2017-01-01

    Full Text Available Objective. The aim of this study was to assess the behavior of red tilapia juveniles (Oreochromis sp. in presence of the possible probiotic microorganisms isolated from the gastrointestinal tract of panche fish (Hypostomus plecostomus. Materials and methods. During the phase of assessment of probiotics, 120 red tilapia (Oreochromis sp juveniles were selected, with average weight of 1.28±0.22 g and average length of 2.99±0.27 cm. Three experimental treatments were formulated taking into account the nourishment needs of red tilapia (Oreochromis sp.. The statistical method employed was a completely random design. Results. The three strains of Lactobacillus genus (Lactobacillus plantarum, Lactobacillus pentosus, Lactobacillus rhamnosus isolated from the digestive tract of H. plecostomus, yielded diverse results in the biometrical variables considered, as well as in the SGR, PER, AE, AC. Conclusions. The best rapports regarding the gain in length were for the treatment with native probiotics, and it is deduced that they were easily settled in the intestines of the fish (Oreochromis sp.. It is also determined that there are significant differences in the results or gain in length for the Control Concentrate feed (CC against Concentrate feed plus Native Probiotic (CNP for red tilapia (Oreochromis sp. in the juvenile stag for a 30 day time span.

  7. Shortcut nitrification-denitrification by means of autochthonous halophilic biomass in an SBR treating fish-canning wastewater.

    Science.gov (United States)

    Capodici, Marco; Corsino, Santo Fabio; Torregrossa, Michele; Viviani, Gaspare

    2018-02-15

    Autochthonous halophilic biomass was cultivated in a sequencing batch reactor (SBR) aimed at analyzing the potential use of autochthonous halophilic activated sludge in treating saline industrial wastewater. Despite the high salt concentration (30 g NaCl L -1 ), biological oxygen demand (BOD) and total suspended solids (TSS), removal efficiencies were higher than 90%. More than 95% of the nitrogen was removed via a shortcut nitrification-denitrification process. Both the autotrophic and heterotrophic biomass samples exhibited high biological activity. The use of autochthonous halophilic biomass led to high-quality effluent and helped to manage the issues related to nitrogen removal in saline wastewater treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Effects of antibiotics and ultraviolet radiation on the halophilic blue-green alga

    International Nuclear Information System (INIS)

    Yopp, J.H.; Albright, G.; Miller, D.M.; Southern Illinois Univ., Carbondale

    1979-01-01

    The effects of a variety of antibiotics, ultraviolet radiation and N-methyl-N-nitro-N-nitro-N-nitrosoguanidine (NTG) on the survival and mutability of the halophilic blue-green alga, Aphanothece halophytica, were determined. The halophile was found extremely sensitive to penicillin G and bacitracin; moderately sensitive to novobiocin, amino acid analogs, chloramphenicol and streptomycin; and tolerant to actidione and hydroxyurea. Ultraviolet and NTG killing curves and photoreactivation capabilities were seimilar to those reported for other members of the Chroococcales. Three stable morphological mutants were obtained by ultraviolet and NTG treatment, the latter being much more efficient in the production of mutants. (orig.)

  9. Atrazine- tolerant native microorganisms isolated from agricultural soils in the department of Cordoba, Colombia

    Directory of Open Access Journals (Sweden)

    Luis Oviedo Z

    2017-05-01

    Full Text Available The objective of the present study was to identify and evaluate atrazine tolerant native microorganisms isolated from a soil destined to the maize crop for ensiling, where this pesticide is usually used as preemergence. To determine their tolerance, they were subjected to growth at different concentrations of atrazine, different temperatures (30 ° C, 37 ° C and 40 ° C and pH (5.0, 6.0 and 9.0. The results show native strains that tolerated concentrations of 1000 ppm atrazine, identified as Pseudomonas sp (strain 1L1a, Pseudomona sp (strain 1L2, Streptomyces sp and Arthrobacterium sp, which show higher growth at 37 °C (7. 98E+06 CFU/mL, lower at 30 °C (3.63E+06 CFU/mL and tolerance at 40 °C (5.80E+06 CFU/mL. The strain Streptomyces sp reached its highest growth (4.73E+06 UFC/mL at pH 9.0, while Pseudomonas sp strain 1L1a (3.43E+06 UFC/mL, Arthrobacter sp (3.40E+06 UFC/mL and Pseudomonas sp strain 1L2a (2.63E+06 CFU/mL was at pH 6.0. All microorganisms showed sensitivity to pH 5.0. The growths reached at different temperatures and pH are in agreement with the adaptation to the tropical climate predominant in the region and related to the genus of microorganisms. The study indicates that the native strains are able to tolerate high concentrations of atrazine and to mineralize it in soils with low content of organic matter and nutrients.

  10. New insights into microbial adaptation to extreme saline environments

    Directory of Open Access Journals (Sweden)

    Vauclare P.

    2014-02-01

    Full Text Available Extreme halophiles are microorganisms adapted to low water activity living at the upper salt concentration that life can tolerate. We review here recent data that specify the main factors, which determine their peculiar salt-dependent biochemistry. The data suggested that evolution proceeds by stage to modify the molecular dynamics properties of the entire proteome. Extreme halophiles therefore represent tractable models to understand how fast and to what extent microorganisms adapt to environmental changes. Halophiles are also robust organisms, capable to resist multiple stressors. Preliminary studies indicated that they have developed a cellular response specifically aimed to survive when the salt condition fluctuates. Because of these properties halophilic organisms deserve special attention in the search for traces of life on other planets.

  11. isolation and identification of the microorganisms most prevalent

    African Journals Online (AJOL)

    problems presenting in eye clinics on a daily basis. With one or two ... microorganisms most prevalent in external eye infections in Owerri urban (as seen Mercy Eye clinic). With the aid of sterile .... through personal contacts. Consequently, the.

  12. Marinobacter lacisalsi sp. nov., a moderately halophilic bacterium isolated from the saline-wetland wildfowl reserve Fuente de Piedra in southern Spain.

    Science.gov (United States)

    Aguilera, Margarita; Jiménez-Pranteda, Maria L; Kharroub, Karima; González-Paredes, Ana; Durban, Juan J; Russell, Nick J; Ramos-Cormenzana, Alberto; Monteoliva-Sánchez, Mercedes

    2009-07-01

    A Gram-negative, non-spore-forming, motile, moderately halophilic, aerobic, rod-shaped bacterium, designated strain FP2.5(T), was isolated from the inland hypersaline lake Fuente de Piedra, a saline-wetland wildfowl reserve located in the province of Málaga in southern Spain. Strain FP2.5(T) was subjected to a polyphasic taxonomic study. It produced colonies with a light-yellow pigment. Strain FP2.5(T) grew at salinities of 3-15 % (w/v) and at temperatures of 20-40 degrees C. The pH range for growth was 5-9. Strain FP2.5(T) was able to utilize various organic acids as sole carbon and energy source. Its major fatty acids were C(16 : 0), C(18 : 1)omega9c and C(16 : 1)omega9c. The DNA G+C content was 58.6 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain FP2.5(T) appeared to be a member of the genus Marinobacter and clustered closely with the type strains of Marinobacter segnicrescens, Marinobacter bryozoorum and Marinobacter gudaonensis (levels of 16S rRNA gene sequence similarity of 98.1, 97.4 and 97.2 %, respectively). However, DNA-DNA relatedness between the new isolate and the type strains of its closest related Marinobacter species was low; levels of DNA-DNA relatedness between strain FP2.5(T) and M. segnicrescens LMG 23928(T), M. bryozoorum DSM 15401(T) and M. gudaonensis DSM 18066(T) were 36.3, 32.1 and 24.9 %, respectively. On the basis of phenotypic characteristics, phylogenetic analysis and DNA-DNA relatedness data, strain FP2.5(T) is considered to represent a novel species of the genus Marinobacter, for which the name Marinobacter lacisalsi sp. nov. is proposed. The type strain is FP2.5(T) (=CECT 7297(T)=LMG 24237(T)).

  13. Lipids of the ultra-thin square halophilic archaeon Haloquadratum walsbyi

    Directory of Open Access Journals (Sweden)

    Simona LoBasso

    2008-01-01

    Full Text Available The lipid composition of the extremely halophilic archaeon Haloquadratum walsbyi was investigated by thin-layer chromatography and electrospray ionization-mass spectrometry. The analysis of neutral lipids showed the presence of vitamin MK-8, squalene, carotene, bacterioruberin and several retinal isomers. The major polar lipids were phosphatidylglycerophosphate methyl ester, phosphatidylglycerosulfate, phosphatidylglycerol and sulfated diglycosyl diether lipid. Among cardiolipins, the tetra-phytanyl or dimeric phospholipids, only traces of bisphosphatidylglycerol were detected. When the cells were exposed to hypotonic medium, no changes in the membrane lipid composition occurred. Distinguishing it from other extreme halophiles of the Halobacteriaceae family, the osmotic stress did not induce the neo-synthesis of cardiolipins in H. walsbyi. The difference may depend on the three-laminar structure of the cell wall, which differs significantly from that of other Haloarchaea.

  14. Purification and characterization of halophilic lipase of Chromohalobacter sp. from ancient salt well.

    Science.gov (United States)

    Ai, Li; Huang, Yaping; Wang, Chuan

    2018-06-04

    A halophilic lipase (LipS2) was produced by Chromohalobacter canadensis strain which was isolated from ancient salt well of Zigong, China. LipS2 was purified to homogeneity and showed a single band with molecular mass of 58 kDa by SDS-PAGE. LipS2 preferred middle-to-long acyl chain esters with C14 triglycerides as optimum substrate. It was noteworthy that LipS2 displayed efficient hydrolysis activity to some vegetable oils which were composed of polyunsaturated fatty acid. LipS2 showed high activity in range of 2.5-3.5 M NaCl, no activity without salt. Optimum temperature and pH were 55 °C and pH 8.5, respectively. Notably, the thermostability and pH stability of LipS2, varying with salt concentration, reached optimum in the presence of 3.0 M NaCl. LipS2 was stimulated by Ca 2+ and Mg 2+ , inhibited by Zn 2+ , Cu 2+ , Mn 2+ , Fe 2+ , and Hg 2+ . Moreover, LipS2 displayed significant tolerance to organic solvents including methanol, ethanol, ethyl acetate and acetone, especially, LipS2 activity was enhanced markedly by the hexane and benzene. Non-ionic surfactants increased LipS2 activity, while ionic surfactants decreased activity. This was the first report on halophilic lipase of Chromohalobacter from ancient salt well. The results suggested that LipS2 may have considerable potential for biotechnological applications. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Natronolimnobius aegyptiacus sp. nov., an extremely halophilic alkalithermophilic archaeon isolated from the athalassohaline Wadi An Natrun, Egypt.

    Science.gov (United States)

    Zhao, Baisuo; Hu, Qingping; Guo, Xiaomeng; Liao, Ziya; Sarmiento, Felipe; Mesbah, Noha M; Yan, Yanchun; Li, Jun; Wiegel, Juergen

    2018-02-01

    An obligately aerobic extremely halophilic alkalithermophilic archaeon, strain JW/NM-HA 15 T , was isolated from the sediments of Wadi An Natrun in Egypt. Phylogenetic analysis based on 16S rRNA and rpoB' gene sequences indicated that it belongs to the family Natrialbaceae of the order Natrialbales. The closest relatives were Natronolimnobius baerhuensis IHC-005 T and Natronolimnobius innermongolicus N-1311 T (95.3 and 94.5 % 16S rRNA gene sequence similarity, respectively). Genome relatedness between strain JW/NM-HA 15 T and its neighbours was evaluated using average nucleotide identity, digital DNA-DNA hybridization and average amino acid identity with the values of 75.7-85.0, 18.1-20.0, and 70.2-71.0%, respectively. Cells were obligately aerobic, rod-shaped, non-motile, Gram-stain-negative and chemo-organotrophic. The strain grew in the presence of 2.57 M to saturating Na + (optimum 3.25-4.60 M Na + ), at pH 55 °C 7.5-10.5 (optimum pH 55 °C 9.0-9.5), and at 30-56 °C (optimum 52 °C). The major polar lipids consisted of phosphatidylglycerol, methylated phosphatidylglycerolphosphate and two phospholipids. The complete genome size of strain JW/NM-HA 15 T is approximately 3.93 Mb, with a DNA G+C content of 64.1 mol%. On the basis of phylogenetic features, genomic relatedness, phenotypic and chemotaxonomic data, strain JW/NM-HA 15 T was thus considered to represent a novel species within the genus Natronolimnobius, for which the name Natronolimnobius aegyptiacus sp. nov. is proposed. The type strain is JW/NM-HA 15 T (=ATCC BAA-2088 T =DSM 23470 T ).

  16. Methylohalobius crimeensis gen. nov., sp. nov., a moderately halophilic, methanotrophic bacterium isolated from hypersaline lakes of Crimea.

    Science.gov (United States)

    Heyer, Jürgen; Berger, Ursula; Hardt, Martin; Dunfield, Peter F

    2005-09-01

    A novel genus and species are proposed for two strains of methanotrophic bacteria isolated from hypersaline lakes in the Crimean Peninsula of Ukraine. Strains 10Ki(T) and 4Kr are moderate halophiles that grow optimally at 1-1.5 M (5.8-8.7%, w/v) NaCl and tolerate NaCl concentrations from 0.2 M up to 2.5 M (1.2-15%). This optimum and upper limit are the highest for any methanotrophic bacterium known to date. The strains are Gram-negative, aerobic, non-pigmented, motile, coccoid to spindle-shaped bacteria that grow on methane or methanol only and utilize the ribulose monophosphate pathway for carbon assimilation. They are neutrophilic (growth occurs only in the range pH 6.5-7.5) and mesophilic (optimum growth occurs at 30 degrees C). On the basis of 16S rRNA gene sequence phylogeny, strains 10Ki(T) and 4Kr represent a type I methanotroph within the 'Gammaproteobacteria'. However, the 16S rRNA gene sequence displays <91.5 % identity to any public-domain sequence. The most closely related methanotrophic bacterium is the thermophilic strain HB. The DNA G+C content is 58.7 mol%. The major phospholipid fatty acids are 18:1omega7 (52-61%), 16:0 (22-23%) and 16:1omega7 (14-20%). The dominance of 18:1 over 16:0 and 16:1 fatty acids is unique among known type I methanotrophs. The data suggest that strains 10Ki(T) and 4Kr should be considered as belonging to a novel genus and species of type I methanotrophic bacteria, for which the name Methylohalobius crimeensis gen. nov., sp. nov. is proposed. Strain 10Ki(T) (=DSM 16011(T)=ATCC BAA-967(T)) is the type strain.

  17. The crystal structure of Haloferax volcanii proliferating cell nuclear antigen reveals unique surface charge characteristics due to halophilic adaptation

    Directory of Open Access Journals (Sweden)

    Morroll Shaun

    2009-08-01

    Full Text Available Abstract Background The high intracellular salt concentration required to maintain a halophilic lifestyle poses challenges to haloarchaeal proteins that must stay soluble, stable and functional in this extreme environment. Proliferating cell nuclear antigen (PCNA is a fundamental protein involved in maintaining genome integrity, with roles in both DNA replication and repair. To investigate the halophilic adaptation of such a key protein we have crystallised and solved the structure of Haloferax volcanii PCNA (HvPCNA to a resolution of 2.0 Å. Results The overall architecture of HvPCNA is very similar to other known PCNAs, which are highly structurally conserved. Three commonly observed adaptations in halophilic proteins are higher surface acidity, bound ions and increased numbers of intermolecular ion pairs (in oligomeric proteins. HvPCNA possesses the former two adaptations but not the latter, despite functioning as a homotrimer. Strikingly, the positive surface charge considered key to PCNA's role as a sliding clamp is dramatically reduced in the halophilic protein. Instead, bound cations within the solvation shell of HvPCNA may permit sliding along negatively charged DNA by reducing electrostatic repulsion effects. Conclusion The extent to which individual proteins adapt to halophilic conditions varies, presumably due to their diverse characteristics and roles within the cell. The number of ion pairs observed in the HvPCNA monomer-monomer interface was unexpectedly low. This may reflect the fact that the trimer is intrinsically stable over a wide range of salt concentrations and therefore additional modifications for trimer maintenance in high salt conditions are not required. Halophilic proteins frequently bind anions and cations and in HvPCNA cation binding may compensate for the remarkable reduction in positive charge in the pore region, to facilitate functional interactions with DNA. In this way, HvPCNA may harness its environment as

  18. The crystal structure of Haloferax volcanii proliferating cell nuclear antigen reveals unique surface charge characteristics due to halophilic adaptation

    Science.gov (United States)

    Winter, Jody A; Christofi, Panayiotis; Morroll, Shaun; Bunting, Karen A

    2009-01-01

    Background The high intracellular salt concentration required to maintain a halophilic lifestyle poses challenges to haloarchaeal proteins that must stay soluble, stable and functional in this extreme environment. Proliferating cell nuclear antigen (PCNA) is a fundamental protein involved in maintaining genome integrity, with roles in both DNA replication and repair. To investigate the halophilic adaptation of such a key protein we have crystallised and solved the structure of Haloferax volcanii PCNA (HvPCNA) to a resolution of 2.0 Å. Results The overall architecture of HvPCNA is very similar to other known PCNAs, which are highly structurally conserved. Three commonly observed adaptations in halophilic proteins are higher surface acidity, bound ions and increased numbers of intermolecular ion pairs (in oligomeric proteins). HvPCNA possesses the former two adaptations but not the latter, despite functioning as a homotrimer. Strikingly, the positive surface charge considered key to PCNA's role as a sliding clamp is dramatically reduced in the halophilic protein. Instead, bound cations within the solvation shell of HvPCNA may permit sliding along negatively charged DNA by reducing electrostatic repulsion effects. Conclusion The extent to which individual proteins adapt to halophilic conditions varies, presumably due to their diverse characteristics and roles within the cell. The number of ion pairs observed in the HvPCNA monomer-monomer interface was unexpectedly low. This may reflect the fact that the trimer is intrinsically stable over a wide range of salt concentrations and therefore additional modifications for trimer maintenance in high salt conditions are not required. Halophilic proteins frequently bind anions and cations and in HvPCNA cation binding may compensate for the remarkable reduction in positive charge in the pore region, to facilitate functional interactions with DNA. In this way, HvPCNA may harness its environment as opposed to simply surviving in

  19. Draft genome sequence of Dethiosulfovibrio salsuginis DSM 21565T an anaerobic, slightly halophilic bacterium isolated from a Colombian saline spring.

    Science.gov (United States)

    Díaz-Cárdenas, Carolina; López, Gina; Alzate-Ocampo, José David; González, Laura N; Shapiro, Nicole; Woyke, Tanja; Kyrpides, Nikos C; Restrepo, Silvia; Baena, Sandra

    2017-01-01

    A bacterium belonging to the phylum Synergistetes , genus Dethiosulfovibrio was isolated in 2007 from a saline spring in Colombia. Dethiosulfovibrio salsuginis USBA 82 T ( DSM 21565 T = KCTC 5659 T ) is a mesophilic, strictly anaerobic, slightly halophilic, Gram negative bacterium with a diderm cell envelope. The strain ferments peptides, amino acids and a few organic acids. Here we present the description of the complete genome sequencing and annotation of the type species Dethiosulfovibrio salsuginis USBA 82 T . The genome consisted of 2.68 Mbp with a 53.7% G + C . A total of 2609 genes were predicted and of those, 2543 were protein coding genes and 66 were RNA genes. We detected in USBA 82 T genome six Synergistetes conserved signature indels (CSIs), specific for Jonquetella, Pyramidobacter and Dethiosulfovibrio . The genome of D. salsuginis contained, as expected, genes related to amino acid transport, amino acid metabolism and thiosulfate reduction. These genes represent the major gene groups of Synergistetes , related with their phenotypic traits, and interestingly, 11.8% of the genes in the genome belonged to the amino acid fermentation COG category. In addition, we identified in the genome some ammonification genes such as nitrate reductase genes. The presence of proline operon genes could be related to de novo synthesis of proline to protect the cell in response to high osmolarity. Our bioinformatics workflow included antiSMASH and BAGEL3 which allowed us to identify bacteriocins genes in the genome.

  20. Bacillus marismortui sp. nov., a new moderately halophilic species from the Dead Sea.

    Science.gov (United States)

    Arahal, D R; Márquez, M C; Volcani, B E; Schleifer, K H; Ventosa, A

    1999-04-01

    A group of 91 moderately halophilic, Gram-positive, rod-shaped strains were isolated from enrichments prepared from Dead Sea water samples collected 57 years ago. These strains were examined for 117 morphological, physiological, biochemical, nutritional and antibiotic susceptibility characteristics. All strains formed endospores and were motile, strictly aerobic and positive for catalase and oxidase. They grew in media containing 5-25% (w/v) total salts, showing optimal growth at 10% (w/v). Eighteen strains were chosen as representative isolates and were studied in more detail. All these strains had mesodiaminopimelic acid in the cell wall and a DNA G + C content of 39.0-42.8 mol%; they constitute a group with levels of DNA-DNA similarity of 70-100%. The sequences of the 16S rRNA genes of three representative strains (strains 123T, 557 and 832) were almost identical (99.9%), and placed the strains in the low G + C content Gram-positive bacteria. On the basis of their features, these isolates should be regarded as members of a new species of the genus Bacillus, for which the name Bacillus marismortui sp. nov. is proposed. The type strain is strain 123T (= DSM 12325T = ATCC 700626T = CIP 105609T = CECT 5066T).

  1. Enhancement of uranium-accumulating ability of microorganisms by irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Sakaguchi, Takashi; Nakajima, Akira; Tsuruta, Takehiko [Miyazaki Medical Coll., Kiyotake (Japan)

    1998-01-01

    Some microorganisms having excellent ability to accumulate uranium were isolated, from soil and water systems in and around the Ningyo-toge Station of Power Reactor and Nuclear Fuel Development Corporation. The enhancement of uranium-accumulating ability of microorganisms by electron-beam irradiation was examined, and the ability of JW-046 was increased 3-5% by the irradiation. The irradiation affect the growth of some of microorganisms tested. (author)

  2. Halophilic polysulfabetaines-synthesis and study of gelation and thermoresponsive behavior

    NARCIS (Netherlands)

    Vasantha, Vivek Arjunan; Jana, Satyasankar; Parthiban, Anbanandam; Vancso, Julius G.

    2014-01-01

    Polysulfabetaines (PSBs) derived from zwitterionic sulfates (contrary to commonly used polysulfobetaines which are derived from zwitterionic sulfonates) were synthesized for the first time. PSBs dissolved in brine (halophilic), swelled in deionized water and also exhibited reversible and

  3. Protective role of salt in catalysis and maintaining structure of halophilic proteins against denaturation

    Science.gov (United States)

    Sinha, Rajeshwari; Khare, Sunil K.

    2014-01-01

    Search for new industrial enzymes having novel properties continues to be a desirable pursuit in enzyme research. The halophilic organisms inhabiting under saline/ hypersaline conditions are considered as promising source of useful enzymes. Their enzymes are structurally adapted to perform efficient catalysis under saline environment wherein n0n-halophilic enzymes often lose their structure and activity. Haloenzymes have been documented to be polyextremophilic and withstand high temperature, pH, organic solvents, and chaotropic agents. However, this stability is modulated by salt. Although vast amount of information have been generated on salt mediated protection and structure function relationship in halophilic proteins, their clear understanding and correct perspective still remain incoherent. Furthermore, understanding their protein architecture may give better clue for engineering stable enzymes which can withstand harsh industrial conditions. The article encompasses the current level of understanding about haloadaptations and analyzes structural basis of their enzyme stability against classical denaturants. PMID:24782853

  4. MICROORGANISMS ANTIBIOTIC SENSITIVITY DETERMINATION IN URINARY TRACT INFECTIONS

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    Shapovalova O.V.

    2016-06-01

    Full Text Available Introduction. Nowadays Urinary tract infections (UTI are considered to be the most common bacterial infections. Escherichia coli is the most frequently uropathogen. Other microorganisms of the genera Enterococcus, Klebsiella, Enterobacter, Proteus, Morganella, Citrobacter, Serratia, Pseudomonas, Streptococcus, Staphylococcus, Candida are also isolated with variable frequency. In recent years there has been a decreasing tendency of the causative agents of UTI sensitivity to various antibiotics, which causes growth of an inefficiency treatment risk. In connection with the above the investigations were carried out with the purpose to identify the actual causative agents of bacteriuria and their sensitivity to antibiotics and antifungal drugs. Materials and methods. Bacteriological examination of urine was performed at 42 patients of SI "Sytenko Institute of Spine and Joint Pathology, AMS of Ukraine" clinic. The bacteriological method for determining the number of bacteria in the test material, cultural and bacterioscopic methods for identifying microorganisms and disk-diffusion method for sensitivity of microorganisms to antibiotics determining were used. The clinical material for the study was an average portion of the morning urine or urine collected by catheter. The biological material collection and bacteriological examination was carried by quantitative method, the isolated microorganisms identification and their sensitivity to antibiotics determining was performed by standard methods in accordance with current guidelines. We used the following antibiotics group to determine the microorganisms sensitivity: penicillin, cephalosporin, karbapenems, tetracyclines, aminoglycoside, fluoroquinolones, oxazolidinones, macrolides, lincosamides, glycopeptides, antifungal antibiotics. Results and discussion. During the biological material study 55 isolates of bacterial and fungal pathogens were obtained. The microorganisms’ concentration in urine was in

  5. Using the second law of thermodynamics for enrichment and isolation of microorganisms to produce fuel alcohols or hydrocarbons.

    Science.gov (United States)

    Kohn, Richard A; Kim, Seon-Woo

    2015-10-07

    Fermentation of crops, waste biomass, or gases has been proposed as a means to produce desired chemicals and renewable fuels. The second law of thermodynamics has been shown to determine the net direction of metabolite flow in fermentation processes. In this article, we describe a process to isolate and direct the evolution of microorganisms that convert cellulosic biomass or gaseous CO2 and H2 to biofuels such as ethanol, 1-butanol, butane, or hexane (among others). Mathematical models of fermentation elucidated sets of conditions that thermodynamically favor synthesis of desired products. When these conditions were applied to mixed cultures from the rumen of a cow, bacteria that produced alcohols or alkanes were isolated. The examples demonstrate the first use of thermodynamic analysis to isolate bacteria and control fermentation processes for biofuel production among other uses. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Nesterenkonia pannonica sp. nov., a novel alkaliphilic and moderately halophilic actinobacterium.

    Science.gov (United States)

    Borsodi, Andrea K; Szili-Kovács, Tibor; Schumann, Peter; Spröer, Cathrin; Márialigeti, Károly; Tóth, Erika

    2017-10-01

    An alkaliphilic and moderately halophilic bacterial strain characterized by optimal growth at pH 9.0-10.0 and with 5-7 % (w/v) NaCl, designated BV-35 T , was isolated from water of a soda pan located in Kiskunság National Park, Hungary. Cells of the orange-pigmented colony were Gram-stain-positive, non-motile and non-endospore-forming coccoid rods. The isolate was strictly aerobic, catalase-positive and oxidase-negative. Strain BV-35 T displayed a peptidoglycan similar to type A4α, l-Lys-l-Glu (A11.54 according to www.peptidoglycan-types.info) but containing additionally 4-aminobutyric acid. Menaquinone-7 (MK-7) was the predominant isoprenoid quinone, and anteiso-C15 : 0 and anteiso-C17 : 0 were its major cellular fatty acids. The DNA G+C content of strain BV-35 T was 65.4 mol%. Based on 16S rRNA gene sequence similarities, the novel isolate showed the closest relationship to Nesterenkonia populi GP 10-3 T (97.9 %). The DNA-DNA relatedness between BV-35 T and N. populi was 46.7 %. The distinguishing phenotypic and genetic results of this polyphasic study revealed that strain BV-35 T represents a novel member of the genus Nesterenkonia, for which the name Nesterenkonia pannonica sp. nov. is proposed. The type strain is BV-35 T (=DSM 29786 T =NCAIM B 02606 T ).

  7. Yield emulsifiers exopolysaccharides produced by native halophilic bacteria concentrations molasses three Saccharum officinarum L. "sugarcane"

    Directory of Open Access Journals (Sweden)

    Ángel Fuentes, Carmen Carreño

    2013-06-01

    Full Text Available The microbial exopolysaccharide with emulsifying properties are an alternative to polymers and chemicals from algae and plants. Its production in molasses as carbon source lowers costs and generates added value to this byproduct of the sugar industry, so the aim of this study was to determine the performance and productivity of EPS emulsifiers by native halophilic bacteria in 20, 30 and 40 gL-1 of molasses. In MY synthetic medium with 5 % w/v of salts, 138 isolates of bacteria obtained from soil samples of salt water and in the districts of San Jose and Santa Rosa, in Lambayeque. In 10.8 % of these gummy colony forming bacteria and grown on glucose as carbon source EPS recovered whose maximum values of the mixtures in water emulsion - oil phase were 63.3 and 56.6 % after 1 and 24 hours, respectively. The M5 bacteria identified as Halomonas C1 10-1 sp. M5 EPS synthesized emulsifiers molasses broth, reaching yields Yp/s of 0.296 gg-1 and 0.200 gg-1 with 20 and 30 gL-1 of molasses respectively, a productivity of 0.016 and 0.017 gL-1 h -1 , not differing significantly between them. With 10 gL-1 glucose was reached Yp/s of 0.171 gg-1 and a productivity of 0.018 gL-1 h -1 . It was shown that the EPS produced native halophilic bacteria utilizing molasses emulsifiers as carbon source.

  8. Discovery of extremely halophilic, methyl-reducing euryarchaea provides insights into the evolutionary origin of methanogenesis

    Science.gov (United States)

    Sorokin, Dimitry Y.; Makarova, Kira S.; Abbas, Ben; Ferrer, Manuel; Golyshin, Peter N.; Galinski, Erwin A.; Ciordia, Sergio; Mena, María Carmen; Merkel, Alexander Y.; Wolf, Yuri I.; van Loosdrecht, Mark C.M.; Koonin, Eugene V.

    2017-01-01

    Methanogenic archaea are major players in the global carbon cycle and in the biotechnology of anaerobic digestion. The phylum Euryarchaeota includes diverse groups of methanogens that are interspersed with non-methanogenic lineages. So far methanogens inhabiting hypersaline environments have been identified only within the order Methanosarcinales. We report the discovery of a deep phylogenetic lineage of extremophilic methanogens in hypersaline lakes, and present analysis of two nearly complete genomes from this group. Within the phylum Euryarchaeota, these isolates form a separate, class-level lineage “Methanonatronarchaeia” that is most closely related to the class Halobacteria. Similar to the Halobacteria, “Methanonatronarchaeia” are extremely halophilic and do not accumulate organic osmoprotectants. The high intracellular concentration of potassium implies that “Methanonatronarchaeia” employ the “salt-in” osmoprotection strategy. These methanogens are heterotrophic methyl-reducers that utilize C1-methylated compounds as electron acceptors and formate or hydrogen as electron donors. The genomes contain an incomplete and apparently inactivated set of genes encoding the upper branch of methyl group oxidation to CO2 as well as membrane-bound heterosulfide reductase and cytochromes. These features differentiates “Methanonatronarchaeia” from all known methyl-reducing methanogens. The discovery of extremely halophilic, methyl-reducing methanogens related to haloarchaea provides insights into the origin of methanogenesis and shows that the strategies employed by methanogens to thrive in salt-saturating conditions are not limited to the classical methylotrophic pathway. PMID:28555626

  9. SCREENING OF THERMOPHYLIC MICROORGANISM FROM IJEN CRATER BANYUWANGI AS PHYTASE ENZYME PRODUCER

    Directory of Open Access Journals (Sweden)

    Aline Puspita Kusumadjaja

    2010-06-01

    Full Text Available Phytase is enzyme which hydrolysis phytic acid to anorganic phosphate and myo-inositol pentakis-, tetrakis-, tris-, bis-, and monophosphate. The use of phytase in feed industry can overcome environment and nutrition problems which were arisen from unmetabolism phytic acid or its salt by poultry, swine and fish. The feed industry needs a thermostable enzyme due to the need of high temperature in pelleting process, i.e. 81 °C. By using thermostabile phytase, the pelleting process will not affect the enzyme activity. Thermostabile phytase can be isolated from microorganism live in hot spring water or volcano crater. In this study, the screening of thermophylic microorganism having thermostabile phytase activity in Ijen Crater, Banyuwangi, has been done. From this process, it was obtained 33 isolates that produce phytase enzyme. Isolate was code by AP-17 yields highest phytase activity, that is 0.0296 U/mL, so this isolate was choosen for further study. The activity of crude phytase enzyme was measured based on the amount of anorganic phosphate that was produced in enzymatic reaction using UV-VIS spectrophotometer at 392 nm. Based on morphology test to identify the gram type of microorganism, isolate AP-17 has a bacill cell type and identified as positive gram bacteria. This isolate was assumed as Bacillus type.   Keywords: Phytase, thermophilic microorganism, phytase activity

  10. ATIVIDADE ENZIMÁTICA DE MICRORGANISMOS ISOLADOS DO JACATUPÉ (Pachyrhizus erosus L. Urban ENZYMATIC ACTIVITY OF MICROORGANISMS ISOLATED FROM YAM BEAN LEGUME (Pachyrhizus erosus L. Urban

    Directory of Open Access Journals (Sweden)

    Tânia L. Montenegro STAMFORD

    1998-10-01

    Full Text Available O isolamento e a identificação de microrganismos produtores de enzimas de interesse comercial, utilizando tubérculos de jacatupé (Pachyrhizus erosus L. Urban, foi o objetivo principal deste trabalho. Isolaram-se microrganismos endofíticos e epifíticos identificados por observação micromorfológica. A avaliação da atividade enzimática das linhagens foi determinada pelo método de difusão em ágar. As sessenta e oito linhagens isoladas dos tubérculos de jacatupé foram cultivadas em meio sólido específico para amilase, lipase, protease e celulase por 96h a 280 C. Os microrganismos epifíticos encontrados foram Pithomyces (7,3%, Aspergillus (19,2%, Fusarium (5,9% e Trichoderma (5,8%, e os endofíticos foram Mucor (7,3%, Rhizopus (10,3%, Bacillus (19,0%, Staphylococcus (10,3% e Nocardiopsis (15%. As linhagens de Nocardiopsis sp. apresentaram atividade lipolítica superior à do padrão, porém a atividade amilolítica não apresentou diferença significativa comparada com o padrão. As linhagens de Mucor sp., Pithomyces sp. e Staphylococcus sp. produziram atividade proteolítica abaixo do padrão. Nenhum isolado apresentou atividade celulolítica.The isolation and identification of microorganisms that produce enzyme of commercial interest utilizing tubers of yam bean legume (Pachyrrizus erosus L. Urban was the main objective of this work. Endophytic and epiphytic microorganisms were isolated by micromorphologyc observation. The agar diffusion method was used to determine the enzymatic activity. Sixty-eight isolates from yam bean tubers were cultured at 280 C in solid medium specific to amylase, lipase, protease and cellulase for 96h. The epiphytic microorganisms Pithomyces (7,3%, Aspergillus (19,2%, Fusarium (5,9% and Trichoderma (5,8% and the endophytic microorganisms Mucor (7,3%, Rhizopus (10,3% Bacillus (19%, Staphylococcus (10,3% and Nocardiopsis (15% were isolated. Compared to the specific standard culture Nocardiopsis sp. showed

  11. Biomineralization of carbonate and phosphate by moderately halophilic bacteria

    NARCIS (Netherlands)

    Sánchez-Román, Mónica; Rivadeneyra, Maria A.; Vasconcelos, Crisogono; McKenzie, Judith A.

    We investigated the precipitation of carbonate and phosphate minerals by 19 species of moderately halophilic bacteria using media with variable Mg 2+/Ca2+ ratios. The precipitated minerals were calcite, magnesium (Mg) calcite, and struvite (MgNH4PO4· 6H2O) in variable proportions depending on the

  12. Organic acids production by rhizosphere microorganisms isolated from a Typic Melanudands and its effects on the inorganic phosphates solubilization

    Directory of Open Access Journals (Sweden)

    Eduardo José Serna Posso

    2017-04-01

    Full Text Available It has been established that organic acid secretion by rhizosphere microorganisms is one of the mechanisms to solubilize the phosphorus (P attached to insoluble mineral compounds in soil. This action is an important biotechnological alternative, especially in those soils where high fixation of this nutrient occurs, a very common situation in the tropics. This research evaluated the ability performed by five bacterial and five fungal isolates from Typic Melanudands soil to produce organic acids and generate available phosphorus from insoluble P sources. Given these concerns, the selected microorganisms were replicated for 7 days in liquid medium Pikovskaya (PVK modified sources tricalcium phosphate (P-Ca, aluminum phosphate (P-Al and iron phosphate (P-Fe. The results indicated that phosphorus availability in the media, correlates positively with the organic acids production in each of the sources used (P-Ca (0.63, P-Al (0.67 and P-Fe (0.63. In turn, the chemical processes linked to the phosphates solubilization (e.g., Ca availability affected the development of the microorganisms tested. Both, fungi and bacteria varied in their ability production and type of metabolized organic acids, the most frequent were as follows: citric and gluconic acid.

  13. Application of thermotolerant microorganisms for biofertilizer preparation.

    Science.gov (United States)

    Chen, Kuo-Shu; Lin, Yann-Shying; Yang, Shang-Shyng

    2007-12-01

    Intensive agriculture is practised in Taiwan, and compost application is very popular as a means of improving the soil physical properties and supplying plant nutrition. We tested the potential of inoculation with thermotolerant microorganisms to shorten the maturity and improve the quality of biofertilizer prepared by composting. Thermotolerant microorganisms were isolated from compost and reinoculated for the preparation of biofertilizer. The physical, chemical and biological properties of the biofertilizer were determined during composting. The effects of biofertilizer application on the growth and yield of rape were also studied. Among 3823 colonies of thermotolerant microorganisms, Streptomyces thermonitrificans NTU-88, Streptococcus sp. NTU-130 and Aspergillus fumigatus NTU-132 exhibited high growth rates and cellulolytic and proteolytic activities. When a mixture of rice straw and swine manure were inoculated with these isolates and composted for 61 days, substrate temperature increased initially and then decreased gradually during composting. Substrate pH increased from 7.3 to 8.5. Microbial inoculation enhanced the rate of maturity, and increased the content of ash and total and immobilized nitrogen, improved the germination rate of alfalfa seed, and decreased the content of total organic carbon and the carbon/nitrogen ratio. Biofertilizer application increased the growth and yield of rape. Inoculation of thermotolerant and thermophilic microorganisms to agricultural waste for biofertilizer preparation enhances the rate of maturity and improves the quality of the resulting biofertilizer. Inoculation of appropriate microorganisms in biofertilizer preparation might be usefully applied to agricultural situations.

  14. Antimicrobial activity of jasmine oil against oral microorganisms

    Science.gov (United States)

    Thaweboon, S.; Thaweboon, B.; Kaypetch, R.

    2018-02-01

    Jasmine sambac is a species of jasmine indigenous to the tropical and warm temperature regions in particular West and Southeast Asia. Essential oil extracted from the flowers of J. sambac has been shown to have anti-oxidant activity. However, very little information regarding antimicrobial activity especially oral microorganisms exists. Objective: To investigate antimicrobial effect of essential oil extracted from flowers of J. sambac against various oral microorganisms. Materials and Methods: Oral microbial strains used in the study were Streptococcus mutans KPSK2, Staphylococcus aureus ATCC 5638, Lactobacillus casei ATCC 6363, Klebsiella pneumoniae (clinical isolate), Escherichia coli ATCC 25922, Candida albicans ATCC 10231, Candida krusei ATCC 6258, Candida parapsilosis ATCC 22019, Candida tropicalis (clinical isolate), Candida glabrata ATCC 90030, Candida pseudotropicalis (clinical isolate) and Candida stellatoidia (clinical isolate). The potential of microbial growth inhibition of the oil was firstly screened by Kirby-Bauer disk diffusion method and then the minimum inhibitory concentration (MIC) was determined by agar dilution method. Results: Jasmine oil showed antimicrobial activities against S. mutans, L. casei, E. coli and all strains of Candida species with the zones of inhibition ranging from 9 to 26 mm and MIC values of 0.19-1.56 %v/v. Conclusion: Results from the present study are scientific evidence to demonstrate that jasmine oil could be employed as a natural antimicrobial agent against oral microorganisms.

  15. Screening of microorganisms for microbial enhanced oil recovery processes

    Energy Technology Data Exchange (ETDEWEB)

    Yonebayashi, H. [Japan National Oil Corp., Tokyo (Japan); Yoshida, S. [Japan Food Research Laboratiories, Tokyo (Japan). Div. of Microbiology; Ono, K. [Japan National Oil Corp., Chiba (Japan). Tech. Research Center; Enomoto, H. [Tohoku University, Sendai (Japan). Dept. of Geoscience and Tech.

    2000-01-01

    The objective of this study is to screen effective microorganisms for the Microbial Enhanced Oil Recovery process (or simply as MEOR). Samples of drilling cuttings, formation water, and soil were collected from domestic drilling sites and oil fields. Moreover, samples of activated-sludge and compost were collected from domestic sewage treatment facility and food treatment facility. At first, microorganisms in samples were investigated by incubation with different media; then they were isolated. By two stage-screening based on metabolizing ability, 4 strains (Bacillus licheniformis TRC-18-2-a, Enterobacter cloacae TRC-322, Bacillus subtilis TRC-4118, and Bacillus subtilis TRC-4126) were isolated as effective microorganisms for oil recovery. B. licheniformis TRC-18-2-a is a multifunctional microorganism possessing excellent surfactant productivity, and in addition it has gas, acid and polymer productivities. E. cloacae TRC-332 has gas and acid producing abilities. B. subtilis TRC-4118 and TRC-4126 are effective biosurfactant producers, and they reduce the interfacial tension to 0.04 and 0.12 dyne/cm, respectively. (author)

  16. Dissimilatory Sb(V) reduction by microorganisms isolated from Sb-contaminated sediment

    Science.gov (United States)

    Dovick, M. A.; Kulp, T. R.

    2013-12-01

    this isolate exhibited Sb(V)-dependent heterotrophic growth. These results suggest that the endogenous microbial community from this Sb-contaminated site includes anaerobic microorganisms capable of obtaining energy for growth by oxidizing heterotrophic electron donors using Sb(V) as the terminal electron acceptor. Ongoing work includes identification of the isolated organism using 16S rDNA phylogenetic markers as well as an inventory of known functional genes (e.g., arrA) within this isolate that may more typically encode for As(V)-reduction. These results elucidate the potentially significant role of microbiological transformations in controlling the speciation of Sb in the environment, and may help to identify potential bioremediation strategies for Sb contaminated waters.

  17. Extremely halophilic archaea from ancient salt sediments and their possible survival in halite fluid inclusions

    Science.gov (United States)

    Stan-Lotter, H.; Fendrihan, S.; Gerbl, F. W.; Dornmayr-Pfaffenhuemer, M.; Frethem, C.

    2008-09-01

    Halophilic archaebacteria (haloarchaea) thrive in environments with salt concentrations approaching saturation, such as natural brines, marine solar salterns and alkaline salt lakes; they have also been isolated from ancient subsurface salt sediments of great geological age (195-280 million years) and some of those strains were described as novel species (1). The cells survived perhaps while being enclosed within small fluid inclusions in the halite. The characterization of subsurface microbial life is of astrobiological relevance since extraterrestrial halite has been detected and since microbial life on Mars, if existent, may have retreated into the subsurface. We attempted to simulate the embedding process of extremely halophilic archaea and to analyse any cellular changes which might occur. When enclosing haloarchaea in laboratory grown halite, cells accumulated preferentially in fluid inclusions, as could be demonstrated by pre-staining with fluorescent dyes. With increased time of embedding, rod-shaped cells of Halobacterium salinarum strains were found to assume roundish morphologies. Upon dissolution of the salt crystals, these spheres were stable and viable for months when kept in buffers containing 4 M NaCl. Scanning electron microscopy (SEM) following fixation with glutaraldehyde suggested a potentially gradual transformation from rods to spheres. This notion was supported by fluorescence microscopy of Halobacterium cells, following embedding in halite and staining with SYTO 9. One-dimensional protein patterns of rods and spheres, following SDS polyacrylamide gel electrophoresis, were similar except that the S-layer protein appeared reduced by about 15 - 20 % in spheres. The reddish-orange pigmentation of spheres was much lighter compared to that of rod-shaped cells, suggesting lowered concentrations of carotenoids; this was confirmed by extraction and spectrometry of pigments. The data suggested that Halobacterium cells are capable of forming specific

  18. Efficacy of a marine bacterial nuclease against biofilm forming microorganisms isolated from chronic rhinosinusitis.

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    Robert C Shields

    Full Text Available BACKGROUND: The persistent colonization of paranasal sinus mucosa by microbial biofilms is a major factor in the pathogenesis of chronic rhinosinusitis (CRS. Control of microorganisms within biofilms is hampered by the presence of viscous extracellular polymers of host or microbial origin, including nucleic acids. The aim of this study was to investigate the role of extracellular DNA in biofilm formation by bacteria associated with CRS. METHODS/PRINCIPAL FINDINGS: Obstructive mucin was collected from patients during functional endoscopic sinus surgery. Examination of the mucous by transmission electron microscopy revealed an acellular matrix punctuated occasionally with host cells in varying states of degradation. Bacteria were observed in biofilms on mucosal biopsies, and between two and six different species were isolated from each of 20 different patient samples. In total, 16 different bacterial genera were isolated, of which the most commonly identified organisms were coagulase-negative staphylococci, Staphylococcus aureus and α-haemolytic streptococci. Twenty-four fresh clinical isolates were selected for investigation of biofilm formation in vitro using a microplate model system. Biofilms formed by 14 strains, including all 9 extracellular nuclease-producing bacteria, were significantly disrupted by treatment with a novel bacterial deoxyribonuclease, NucB, isolated from a marine strain of Bacillus licheniformis. Extracellular biofilm matrix was observed in untreated samples but not in those treated with NucB and extracellular DNA was purified from in vitro biofilms. CONCLUSION/SIGNIFICANCE: Our data demonstrate that bacteria associated with CRS form robust biofilms which can be reduced by treatment with matrix-degrading enzymes such as NucB. The dispersal of bacterial biofilms with NucB may offer an additional therapeutic target for CRS sufferers.

  19. Identification of moderately halophilic bacteria from Thai fermented fish ( pla-ra ) and proposal of Virgibacillus siamensis sp. nov.

    Science.gov (United States)

    Tanasupawat, Somboon; Chamroensaksri, Nitcha; Kudo, Takuji; Itoh, Takashi

    2010-10-01

    Forty-one isolates of moderately halophilic bacteria were isolated from fermented fish (pla-ra) in Thailand. On the basis of their phenotypic and chemotaxonomic characteristics, DNA-DNA relatedness and 16S rRNA gene sequences analyses, they were divided into six groups. The isolates in Group I to V were Gram-positive rod-shaped bacteria. They contained meso-diaminopimelic acid in the cell-wall peptidoglycan and menaquinone with seven isoprene units (MK-7). An isolate in Group VI was a Gram-negative rod-shaped bacterium. The DNA G+C contents of tested strains ranged from 36.5-63 mol%. Ten strains (Group I) were identified as Virgibacillus dokdonensis, 13 isolates (Group II) as V. halodenitrificans, 14 isolates (Group III) as V. marismortui, 1 isolate (Group IV) as Virgibacillus sp., 2 isolates (Group V) as Bacillus vietnamnensis, and 1 isolate (Group VI) as Chromohalobacter salexigens. Isolate MS3-4 in Group IV was closely related to V. carmonensis KCTC 3819(T) (95.9%). This strain contained anteiso-C(15:0) (55.8%) and anteiso-C(17:0) (17.7%) as major cellular fatty acids and had phosphatidylglycerol, diphosphatidylglycerol and an unidentified glycolipid as polar lipids. The DNA G+C content of MS3-4 was 38.0 mol%. The strain from Group IV is proposed as Virgibacillus siamensis sp. nov. and MS3-4(T) is the type strain (JCM 15395(T) =PCU 312(T) =TISTR 1957(T)).

  20. Detection of extracellular enzymatic activity in microorganisms ...

    African Journals Online (AJOL)

    Detection of extracellular enzymatic activity in microorganisms isolated from waste vegetable oil contaminated soil using plate methodologies. Eugenia G. Ortiz Lechuga, Isela Quintero Zapata, Katiushka Arévalo Niño ...

  1. Reversible Activation of Halophilic β-lactamase from Methanol-Induced Inactive Form: Contrast to Irreversible Inactivation of Non-Halophilic Counterpart.

    Science.gov (United States)

    Tokunaga, Hiroko; Maeda, Junpei; Arakawa, Tsutomu; Tokunaga, Masao

    2017-06-01

    Effects of a water-miscible organic solvent, methanol, on the structure and activity of halophilic β-lactamase derived from Chromohalobacter sp.560 (HaBla), were investigated by means of circular dichroism (CD) measurement and enzymatic activity determination. Beta-lactamase activity was enhanced about 1.2-fold in the presence of 10-20% methanol. CD measurement of HaBla revealed different structures depending on the methanol concentration: native-like active form (Form I) in 10-20% methanol and methanol-induced inactive form at higher concentration (Form II in 40-60% and Form III in 75-80% methanol). Incubation of HaBla with 40% methanol led to the complete loss of activity within ~80 min accompanied by the formation of Form II, whose activity was recovered promptly up to ~80% of full activity upon dilution of the methanol concentration to 10%. In addition, when the protein concentration was sufficiently high (e.g., 0.7 mg/ml), HaBla activity of Form III in 75% methanol could be recovered in the same way (with slightly slower recovery rate), upon dilution of the methanol concentration. In contrast, non-halophilic β-lactamase from Escherichia coli K12 strain MG1655 (EcBla) was irreversibly denatured in the presence of 40% methanol. HaBla showed remarkable ability to renature from the methanol-induced inactive states.

  2. Haladaptatus pallidirubidus sp. nov., a halophilic archaeon isolated from saline soil samples in Yunnan and Xinjiang, China.

    Science.gov (United States)

    Liu, Bing-Bing; Zhao, Wan-Yu; Chu, Xiao; Hozzein, Wael N; Prabhu, Deene Manik; Wadaan, Mohammed A M; Tang, Shu-Kun; Zhang, Li-Li; Li, Wen-Jun

    2014-11-01

    Two extremely halophilic archaea, designated YIM 90917 and YIM 93656(T), were isolated from saline soils in Yunnan province and Lup nur region in Xinjiang province, western China, respectively. Colonies of the two strains were observed to be pink-pigmented. The cells were found to be Gram-stain negative, coccoid and non-motile. The organisms were found to be aerobic and could grow in an NaCl range of 6-35 % (optimum 18 %), temperatures ranging from 25 to 50 °C (optimum 37-42 °C), pH range from 6.0-8.5 (optimum pH 7.0-7.5) and Mg(2+) range from 0 to 1.5 M (optimum 0.5-1.0 M); Mg(2+) was not necessary for growth. Cells were not observed to lyse in distilled water. Strains YIM 90917 and YIM 93656(T) showed the highest 16S rRNA gene sequence similarities to Haladaptatus cibarius JCM 15962(T) (97.6 and 97.9 %, respectively). In addition, the DNA-DNA hybridizations of strains YIM 90917 and YIM 93656(T) with type strains H. cibarius JCM 15962(T), Haladaptatus litoreus JCM 15771(T) and Haladaptatus paucihalophilus JCM 13897(T) were 37.2 and 38.2 %, 36.6 and 39.0 % and 27.9 and 27.7 %, respectively. The DNA G+C contents of strains YIM 90917 and YIM 93656(T) were determined to be 56.0 and 57.4 mol%. The major polar lipids of the two strains were identified as phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate, sulfated mannosyl glucosyl diether and other four unidentified glycolipids. On the basis of physiological, chemotaxonomic data and phylogenetic analysis, the strains YIM 90917 and YIM 93656(T) can be classified as a novel species of the genus Haladaptatus, for which the name Haladaptatus pallidirubidus sp. nov. is proposed. The type strain is YIM 93656(T) (=JCM 17504(T) = CCTCC AB2010454(T)).

  3. Egibacter rhizosphaerae gen. nov., sp. nov., an obligately halophilic, facultatively alkaliphilic actinobacterium and proposal of Egibaceraceae fam. nov. and Egibacterales ord. nov.

    Science.gov (United States)

    Zhang, Yong-Guang; Wang, Hong-Fei; Yang, Ling-Ling; Zhou, Xing-Kui; Zhi, Xiao-Yang; Duan, Yan-Qing; Xiao, Min; Zhang, Yuan-Ming; Li, Wen-Jun

    2016-01-01

    A novel obligately halophilic, facultatively alkaliphilic actinobacterium, designated EGI 80759T, was isolated from the rhizosphere of Tamarix hispida Willd, Karamay, Xinjiang province, north-west China. Cells of strain EGI 80759T were Gram-stain-positive, non-motile and non-endospore-forming rods. Strain EGI 80759T showed obligately halophilic growth with a tolerance to 8-25 % (w/v) NaCl (optimum growth at 10-12 %, w/v) and facultatively alkaliphilic growth within the pH range 7.0-11.0 (optimum growth at pH 9.0-10.0). Cell-wall hydrolysates of the isolate contained meso-diaminopimelic acid (peptidoglycan type A1γ), with glucose, glucosamine, ribose and mannose as the major sugars. The major fatty acids identified were 10-methyl-C17 : 0, C17 : 1ω8c and C17 : 0. The predominant menaquinone was MK-9(H4). The G+C content of the genomic DNA was 72.1 mol%. Phylogenetic analysis, based on 16S rRNA gene sequences, revealed that strain EGI 80759T clustered with members of the class Nitriliruptoria and showed highest 16S rRNA gene sequence similarities with Euzebya tangerina F10T (90.3 %) and Nitriliruptor alkaliphilus ANL-iso2T (88.1 %). On the basis of the data obtained from phenotypic and chemotaxonomic studies and the phylogenetic analysis, the isolate is proposed to be a representative of a novel genus and a novel species, Egibacter rhizosphaerae gen. nov., sp. nov., of a proposed novel family, Egibacteraceae fam. nov., and order, Egibacterales ord. nov., within the class Nitriliruptoria. The type strain of the type species, Egibacter rhizosphaerae, is EGI 80759T ( = CGMCC 1.14997T = KCTC 39588T).

  4. Analysis of metagenomic data reveals common features of halophilic viral communities across continents.

    Science.gov (United States)

    Roux, Simon; Enault, Francois; Ravet, Viviane; Colombet, Jonathan; Bettarel, Yvan; Auguet, Jean-Christophe; Bouvier, Thierry; Lucas-Staat, Soizick; Vellet, Agnès; Prangishvili, David; Forterre, Patrick; Debroas, Didier; Sime-Ngando, Telesphore

    2016-03-01

    Microbial communities from hypersaline ponds, dominated by halophilic archaea, are considered specific of such extreme conditions. The associated viral communities have accordingly been shown to display specific features, such as similar morphologies among different sites. However, little is known about the genetic diversity of these halophilic viral communities across the Earth. Here, we studied viral communities in hypersaline ponds sampled on the coast of Senegal (8-36% of salinity) using metagenomics approach, and compared them with hypersaline viromes from Australia and Spain. The specificity of hyperhalophilic viruses could first be demonstrated at a community scale, salinity being a strong discriminating factor between communities. For the major viral group detected in all samples (Caudovirales), only a limited number of halophilic Caudovirales clades were highlighted. These clades gather viruses from different continents and display consistent genetic composition, indicating that they represent related lineages with a worldwide distribution. Non-tailed hyperhalophilic viruses display a greater rate of gene transfer and recombination, with uncharacterized genes conserved across different kind of viruses and plasmids. Thus, hypersaline viral communities around the world appear to form a genetically consistent community that are likely to harbour new genes coding for enzymes specifically adapted to these environments. © 2015 Society for Applied Microbiology and John Wiley & Sons Ltd.

  5. [Periodontal microbiota and microorganisms isolated from heart valves in patients undergoing valve replacement surgery in a clinic in Cali, Colombia].

    Science.gov (United States)

    Moreno, Sandra; Parra, Beatriz; Botero, Javier E; Moreno, Freddy; Vásquez, Daniel; Fernández, Hugo; Alba, Sandra; Gallego, Sara; Castillo, Gilberto; Contreras, Adolfo

    2017-12-01

    Periodontitis is an infectious disease that affects the support tissue of the teeth and it is associated with different systemic diseases, including cardiovascular disease. Microbiological studies facilitate the detection of microorganisms from subgingival and cardiovascular samples. To describe the cultivable periodontal microbiota and the presence of microorganisms in heart valves from patients undergoing valve replacement surgery in a clinic in Cali. We analyzed 30 subgingival and valvular tissue samples by means of two-phase culture medium, supplemented blood agar and trypticase soy agar with antibiotics. Conventional PCR was performed on samples of valve tissue. The periodontal pathogens isolated from periodontal pockets were: Fusobacterium nucleatum (50%), Prevotella intermedia/ nigrescens (40%), Campylobacter rectus (40%), Eikenella corrodens (36.7%), Gram negative enteric bacilli (36.7%), Porphyromonas gingivalis (33.3%), and Eubacterium spp. (33.3%). The pathogens isolated from the aortic valve were Propionibacterium acnes (12%), Gram negative enteric bacilli (8%), Bacteroides merdae (4%), and Clostridium bifermentans (4%), and from the mitral valve we isolated P. acnes and Clostridium beijerinckii. Conventional PCR did not return positive results for oral pathogens and bacterial DNA was detected only in two samples. Periodontal microbiota of patients undergoing surgery for heart valve replacement consisted of species of Gram-negative bacteria that have been associated with infections in extraoral tissues. However, there is no evidence of the presence of periodontal pathogens in valve tissue, because even though there were valve and subgingival samples positive for Gram-negative enteric bacilli, it is not possible to maintain they corresponded to the same phylogenetic origin.

  6. Molecular interactions within the halophilic, thermophilic, and mesophilic prokaryotic ribosomal complexes: clues to environmental adaptation.

    Science.gov (United States)

    Mallik, Saurav; Kundu, Sudip

    2015-01-01

    Using the available crystal structures of 50S ribosomal subunits from three prokaryotic species: Escherichia coli (mesophilic), Thermus thermophilus (thermophilic), and Haloarcula marismortui (halophilic), we have analyzed different structural features of ribosomal RNAs (rRNAs), proteins, and of their interfaces. We have correlated these structural features with the environmental adaptation strategies of the corresponding species. While dense intra-rRNA packing is observed in thermophilic, loose intra-rRNA packing is observed in halophilic (both compared to mesophilic). Interestingly, protein-rRNA interfaces of both the extremophiles are densely packed compared to that of the mesophilic. The intersubunit bridge regions are almost devoid of cavities, probably ensuring the proper formation of each bridge (by not allowing any loosely packed region nearby). During rRNA binding, the ribosomal proteins experience some structural transitions. Here, we have analyzed the intrinsically disordered and ordered regions of the ribosomal proteins, which are subjected to such transitions. The intrinsically disordered and disorder-to-order transition sites of the thermophilic and mesophilic ribosomal proteins are simultaneously (i) highly conserved and (ii) slowly evolving compared to rest of the protein structure. Although high conservation is observed at such sites of halophilic ribosomal proteins, but slow rate of evolution is absent. Such differences between thermophilic, mesophilic, and halophilic can be explained from their environmental adaptation strategy. Interestingly, a universal biophysical principle evident by a linear relationship between the free energy of interface formation, interface area, and structural changes of r-proteins during assembly is always maintained, irrespective of the environmental conditions.

  7. Few microorganisms associated with bacterial vaginosis may constitute the pathologic core

    DEFF Research Database (Denmark)

    Thorsen, Poul; Jensen, Inge Panum; Jeune, Bernard

    1998-01-01

    OBJECTIVE: To evaluate the association between various microorganisms isolated from the genital tract in pregnant women with bacterial vaginosis. STUDY DESIGN: A cross-sectional population-based study among pregnant women addressed at their first antenatal visit before 24 full gestational weeks......) between the microorganisms isolated from the lower genital tract in pregnant women with and without clinical diagnosis of bacterial vaginosis. RESULTS: Three thousand five hundred ninety-six (3596) pregnant women were asked to participate. Of the 3596 pregnant women 3174 (88.4%) agreed to participate...

  8. Molecular identification of microorganisms associated to the rhizosphere of vanilla plants in Colombia

    International Nuclear Information System (INIS)

    Alvarez Lopez, Claudia Lucia; Osorio Vega, Nelson Walter; Marin Montoya, Mauricio Alejandro

    2013-01-01

    The cultivation of vanilla (Vanilla planifolia) is highly promising in Colombia, but more research is needed on its agronomical management and beneficial microorganisms that grow associated to its rhizosphere, on which the plant depends for its nutrition and growth. This study involved the identification of microorganisms associated to the rhizosphere of vanilla plants in a crop located in Sopetran, Colombia. The microbes were isolated in selective media for functional groups such as cellulolytic, proteolytic, inorganic and organic phosphate (phytate) solubilizers, and asymbiotic nitrogen fixing bacteria. After isolation and purification, 109 microbial isolates were obtained. DNA was extracted from 52 selected isolates for molecular identification based on its and 16s RDNA sequencing, for fungi and bacteria, respectively. The diversity of rhizosphere microorganisms found was significant. Bacteria such as Bacillus Megaterium, Pseudomonas koreensis and Acinetobacter sp., and the Fungus Plectosphaerella sp., may have a high potential to be used as biofertilizers to improve vanilla plant nutrition and growth.

  9. Bactericidal effect of lactoferrin and lactoferrin chimera against halophilic Vibrio parahaemolyticus

    NARCIS (Netherlands)

    Leon-Sicairos, N.; Canizalez-Roman, A.; de la Garza, M.; Reyes-Lopez, M.; Zazueta-Beltran, J.; Nazmi, K.; Gomez-Gil, B.; Bolscher, J.G.

    2009-01-01

    Infections caused by Vibrio parahaemolyticus, an halophilic member of the genus Vibrio, have increased globally in the last 5 years. Diarrhea caused by V. parahaemolyticus results from eating raw or undercooked seafood. The aim of this work was to investigate whether lactoferrin and some

  10. Ecological aspects of microorganisms inhabiting uranium mill tailings

    Science.gov (United States)

    Miller, C.L.; Landa, E.R.; Updegraff, D.M.

    1987-01-01

    Numbers and types of microorganisms in uranium mill tailings were determined using culturing techniques. Arthrobacter were found to be the predominant microorganism inhabiting the sandy tailings, whereas Bacillus and fungi predominated in the slime tailings. Sulfate-reducing bacteria, capable of leaching radium, were isolated in low numbers from tailings samples but were isolated in significantly high numbers from topsoil in contact with the tailings. The results are placed in the context of the magnitude of uranium mill tailings in the United States, the hazards posed by the tailings, and how such hazards could be enhanced or diminished by microbial activities. Patterns in the composition of the microbial population are evaluated with respect to the ecological variables that influence microbial growth. ?? 1987 Springer-Verlag New York Inc.

  11. Isolation, one-step affinity purification, and characterization of a polyextremotolerant laccase from the halophilic bacterium Aquisalibacillus elongatus and its application in the delignification of sugar beet pulp.

    Science.gov (United States)

    Rezaei, Shahla; Shahverdi, Ahmad Reza; Faramarzi, Mohammad Ali

    2017-04-01

    The aim of the present work was to study the ability of a halophilic bacterial laccase to efficient delignification in extreme conditions. Here, a highly stable extracellular laccase showing ligninolytic activity from halophilic Aquisalibacillus elongatus is described. The laccase production was strongly influenced by NaCl and CuSO 4 and under optimal conditions reached 4.8UmL -1 . The monomeric enzyme of 75kDa was purified by a synthetic affinity column with 68.2% yield and 99.8-fold purification. The enzyme showed some valuable features viz. stability against a wide range of organic solvents, salts, metals, inhibitors, and surfactants and specificity to a wide spectrum of substrates diverse in structure and redox potential. It retained more than 50% of the original activity at 25-75°C and pH 5.0-10.0. Furthermore, the enzyme was found to be effective in the delignification of sugar beet pulp in an ionic liquid that makes it useful for industrial applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Degradation of /sup 14/C-parathion 'in vitro' by microorganisms isolated from a gley humic soil

    Energy Technology Data Exchange (ETDEWEB)

    Andrea, M.M. de; Ruegg, E.F. (Instituto Biologico, Sao Paulo (Brazil). Centro de Radioisotopos)

    It was determined 'in vitro' the degradation of Parathion by a bacterium and a fungus isolated from a sample of Gley Humic soil previously treated with repeated applications of the insecticide. In a qualitative colorimetric assay hydrolysis of parathion to p-nitrophenol just the bacterium gave a positive answer. In quantitative assays of /sup 14/C-parathion degradation in culture media containing both microorganisms, organic solvents extractions resulted in organic and aqueous phases, which were analysed by liquid scintillation counting and thin-layer chromatography. In a mineral salts medium plus buffer, the bacterium and the fungus behaved differently from the control, because part of the /sup 14/C-insecticide was metabolized to, at least, one metabolite and besides, the microorganisms presented smaller percentages of total recovery. The largest percentage of the radio carbon recovery from the extracts of the medium containing the fungus plus extract of yeast, was obtained from the aqueous phase and the existence of other metabolite was demonstrated by chromatograms of the organic phase.

  13. The presence of biofilm forming microorganisms on hydrotherapy equipment and facilities.

    Science.gov (United States)

    Jarząb, Natalia; Walczak, Maciej

    2017-10-01

    Hydrotherapy equipment provides a perfect environment for the formation and growth of microbial biofilms. Biofilms may reduce the microbiological cleanliness of hydrotherapy equipment and harbour opportunistic pathogens and pathogenic bacteria. The aims of this study were to investigate the ability of microorganisms that colonize hydrotherapy equipment to form biofilms, and to assess the influence of temperature and nutrients on the rate of biofilm formation. Surface swab samples were collected from the whirlpool baths, inhalation equipment and submerged surfaces of a brine pool at the spa center in Ciechocinek, Poland. We isolated and identified microorganisms from the swab samples and measured their ability to form biofilms. Biofilm formation was observed at a range of temperatures, in both nutrient-deficient and nutrient-rich environments. We isolated and identified microorganisms which are known to form biofilms on medical devices (e.g. Stenotrophomonas maltophilia). All isolates were classified as opportunistic pathogens, which can cause infections in humans with weakened immunity systems. All isolates showed the ability to form biofilms in the laboratory conditions. The potential for biofilm formation was higher in the presence of added nutrients. In addition, the hydrolytic activity of the biofilm was connected with the presence of nutrients.

  14. Electrode Cultivation and Interfacial Electron Transport in Subsurface Microorganisms

    Science.gov (United States)

    Karbelkar, A. A.; Jangir, Y.; Reese, B. K.; Wanger, G.; Anderson, C.; El-Naggar, M.; Amend, J.

    2016-12-01

    Continental subsurface environments can present significant energetic challenges to the resident microorganisms. While these environments are geologically diverse, potentially allowing energy harvesting by microorganisms that catalyze redox reactions, many of the abundant electron donors and acceptors are insoluble and therefore not directly bioavailable. Microbes can use extracellular electron transfer (EET) as a metabolic strategy to interact with redox active surfaces. This process can be mimicked on electrode surfaces and hence can lead to enrichment and quantification of subsurface microorganisms A primary bioelectrochemical enrichment with different oxidizing and reducing potentials set up in a single bioreactor was applied in situ to subsurface microorganisms residing in iron oxide rich deposits in the Sanford Underground Research Facility. Secondary enrichment revealed a plethora of classified and unclassified subsurface microbiota on both oxidizing and reducing potentials. From this enrichment, we have isolated a Gram-positive Bacillus along with Gram-negative Cupriavidus and Anaerospora strains (as electrode reducers) and Comamonas (as an electrode oxidizer). The Bacillus and Comamonas isolates were subjected to a detailed electrochemical characterization in half-reactors at anodic and cathodic potentials, respectively. An increase in cathodic current upon inoculation and cyclic voltammetry measurements confirm the hypothesis that Comamonas is capable of electron uptake from electrodes. In addition, measurements of Bacillus on anodes hint towards novel mechanisms that allow EET from Gram-positive bacteria. This study suggests that electrochemical approaches are well positioned to dissect such extracellular interactions that may be prevalent in the subsurface, while using physical electrodes to emulate the microhabitats, redox and geochemical gradients, and the spatially dependent interspecies interactions encountered in the subsurface. Electrochemical

  15. Sporosalibacterium faouarense gen. nov., sp. nov., a moderately halophilic bacterium isolated from oil-contaminated soil.

    Science.gov (United States)

    Rezgui, Raja; Ben Ali Gam, Zouhaier; Ben Hamed, Said; Fardeau, Marie-Laure; Cayol, Jean-Luc; Maaroufi, Abderrazak; Labat, Marc

    2011-01-01

    A novel strictly anaerobic, moderately halophilic and mesophilic bacterium, designated strain SOL3f37(T), was isolated from a hydrocarbon-polluted soil surrounding a deep petroleum environment located in south Tunisia. Cells of strain SOL3f37(T) stained Gram-positive and were motile, straight and spore-forming. Strain SOL3f37(T) had a typical Gram-positive-type cell-wall structure, unlike the thick, multilayered cell wall of its closest relative Clostridiisalibacter paucivorans. The major fatty acids were iso-C(15 : 0) (41 %), iso-C(14 : 0) 3-OH and/or iso-C(15 : 0) dimethyl acetal (21.6 %), iso-C(13 : 0) (4.4 %), anteiso-C(15 : 0) (3.9 %) and iso-C(15 : 1) (2.8 %). Strain SOL3f37(T) grew between 20 and 48 °C (optimum 40 °C) and at pH 6.2-8.1 (optimum pH 6.9). Strain SOL3f37(T) required at least 0.5 NaCl l(-1) and grew in the presence of NaCl concentrations up to 150 g l(-1) (optimum 40 g l(-1)). Yeast extract (2 g l(-1)) was required for degradation of pyruvate, fumarate, fructose, glucose and mannitol. Also, strain SOL3f37(T) grew heterotrophically on yeast extract, peptone and bio-Trypticase, but was unable to grow on Casamino acids. Sulfate, thiosulfate, sulfite, elemental sulfur, fumarate, nitrate and nitrite were not reduced. The DNA G+C content was 30.7 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain SOL3f37(T) was a member of the family Clostridiaceae in the order Clostridiales; strain SOL3f37(T) was related to members of various genera of the family Clostridiaceae. It exhibited highest 16S rRNA gene sequence similarity (93.4 %) with Clostridiisalibacter paucivorans 37HS60(T), 91.8 % with Thermohalobacter berrensis CTT3(T) and 91.7 % with Caloranaerobacter azorensis MV1087(T). On the basis of genotypic, phenotypic and phylogenetic data, it is suggested that strain SOL3f37(T) represents a novel species in a new genus. The name Sporosalibacterium faouarense gen. nov., sp. nov. is

  16. Production of beta-xylanase and beta-xylosidase by the extremely halophilic archaeon Halorhabdus utahensis

    DEFF Research Database (Denmark)

    Wainø, M.; Ingvorsen, K.

    2003-01-01

    -xylosidase stabilities, approximately 55% and 83% of the initial beta-xylanase and beta-xylosidase activities, respectively, remained after 24 h incubation at 20% NaCl. The enzymes were also shown to be slightly thermophilic: P-xylanase activity exhibiting two optima at 55degrees and 70degreesC, while beta......The extremely halophilic archaeon, Halorhabdus utahensis, isolated from the Great Salt Lake, Utah, produced beta-xylanase and beta-xylosidase activities. Both enzymes were active over a broad NaCl range from near zero to 30% NaCl when tested with culture broth. A broad NaCl optimum was observed...... for beta-xylanase activity between 5% and 15% NaCl, while beta-xylosidase activity was highest at 5% NaCl. Almost half of the maximum activities remained at 27%-30% NaCl for both enzyme activities. When dialyzed culture supernatant and culture broth were employed for determination of beta-xylanase and beta...

  17. Genomic adaptations of the halophilic Dead Sea filamentous fungus Eurotium rubrum.

    Science.gov (United States)

    Kis-Papo, Tamar; Weig, Alfons R; Riley, Robert; Peršoh, Derek; Salamov, Asaf; Sun, Hui; Lipzen, Anna; Wasser, Solomon P; Rambold, Gerhard; Grigoriev, Igor V; Nevo, Eviatar

    2014-05-09

    The Dead Sea is one of the most hypersaline habitats on Earth. The fungus Eurotium rubrum (Eurotiomycetes) is among the few species able to survive there. Here we highlight its adaptive strategies, based on genome analysis and transcriptome profiling. The 26.2 Mb genome of E. rubrum shows, for example, gains in gene families related to stress response and losses with regard to transport processes. Transcriptome analyses under different salt growth conditions revealed, among other things differentially expressed genes encoding ion and metabolite transporters. Our findings suggest that long-term adaptation to salinity requires cellular and metabolic responses that differ from short-term osmotic stress signalling. The transcriptional response indicates that halophilic E. rubrum actively counteracts the salinity stress. Many of its genes encode for proteins with a significantly higher proportion of acidic amino acid residues. This trait is characteristic of the halophilic prokaryotes as well, supporting the theory of convergent evolution under extreme hypersaline stress.

  18. Compatible Solute Synthesis and Import by the Moderate Halophile Spiribacter salinus: Physiology and Genomics

    Directory of Open Access Journals (Sweden)

    María J. León

    2018-02-01

    . It was amassed in salt-stressed cells in unmodified form and suppressed the synthesis of ectoine. In conclusion, the data presented here allow us to derive a genome-scale picture of the cellular adjustment strategy of a species that represents an environmentally abundant group of ecophysiologically important halophilic microorganisms.

  19. THE ASPECTS OF INVESTIGATION OF MICROORGANISM ANTIBIOTIC RESISTANCE AT THE PRESENT STAGE

    Directory of Open Access Journals (Sweden)

    Andreeva I.A.

    2015-05-01

    Full Text Available Introduction. At the present stage for ensuring epidemic safety and prevention of nosocomial infections the complex of analytical study and managerial procedure to improve the epidemiological supervision over nosocomial infections through the introduction of infection control in health care practice are using. The microbiological monitoring is part of the infectious control and allows supervising circulation of microorganisms and their antimicrobial resistance by dynamic observation over structure and level of resistance to antibiotics that are used in the given particular hospital. Materials and methods. For the dynamic observation of the structure and the level of resistance of microorganisms to antimicrobial agents the computer software WHONET recommended by WHO has been used. With using WHONET in Dnepropetrovsk Children's Hospital № 3 the computer database has been created. In this database the information about each patient, hospital department, samples under test and the date of its excretion, the data about the detected microorganism and its sensitivity/resistance to antimicrobial agents have been stored. The examination and analysis of antibiotic resistance of microorganisms has been provided for 2010- 2014 years, in total the data on 6168 isolates from 3876 patients have been analyzed. Results and discussion. By the total data the isolates belong to a wide spectrum of microorganisms (more than 40 different types. By means of the analysis of isolating of clinically significant microorganisms it has been established that one of the most frequent isolated were Escherichia coli (1-20 %, Klebsiella pneumoniae (4-18 %, Staphylococcus epidermidis (1-12 %, S. aureus (1-10 %, Enterobacter cloacae (2-9 %, Pseudomonas aeruginosa (1-8 %. Detection of other microorganisms was irregular and its frequency is varied from 0 % to 10 %. As a result of examining the sensitivity of microorganisms it has been shown that tested strains of bacteria were

  20. Partial characterization of an extracellular polysaccharide produced by the moderately halophilic bacterium Halomonas xianhensis SUR308.

    Science.gov (United States)

    Biswas, Jhuma; Ganguly, J; Paul, A K

    2015-01-01

    A moderately halophilic bacterium, Halomonas xianhensis SUR308 (Genbank Accession No. KJ933394) was isolated from a multi-pond solar saltern at Surala, Ganjam district, Odisha, India. The isolate produced a significant amount (7.87 g l(-1)) of extracellular polysaccharides (EPS) when grown in malt extract-yeast extract medium supplemented with 2.5% NaCl, 0.5% casein hydrolysate and 3% glucose. The EPS was isolated and purified following the conventional method of precipitation and dialysis. Chromatographic analysis (paper, GC and GC-MS) of the hydrolyzed EPS confirmed its heteropolymeric nature and showed that it is composed mainly of glucose (45.74 mol%), galactose (33.67 mol %) and mannose (17.83 mol%). Fourier-transform infrared spectroscopy indicated the presence of methylene and carboxyl groups as characteristic functional groups. In addition, its proton nuclear magnetic resonance spectrum revealed functional groups specific for extracellular polysaccharides. X-ray diffraction analysis revealed the amorphous nature (CIxrd, 0.56) of the EPS. It was thermostable up to 250 °C and displayed pseudoplastic rheology and remarkable stability against pH and salts. These unique properties of the EPS produced by H. xianhensis indicate its potential to act as an agent for detoxification, emulsification and diverse biological activities.

  1. Halophilic mechanism of the enzymatic function of a moderately halophilic dihydrofolate reductase from Haloarcula japonica strain TR-1.

    Science.gov (United States)

    Miyashita, Yurina; Ohmae, Eiji; Ikura, Teikichi; Nakasone, Kaoru; Katayanagi, Katsuo

    2017-05-01

    Dihydrofolate (DHF) reductase coded by a plasmid of the extremely halophilic archaeon Haloarcula japonica strain TR-1 (HjDHFR P1) shows moderate halophilicity on enzymatic activity at pH 6.0, although there is no significant effect of NaCl on its secondary structure. To elucidate the salt-activation and -inactivation mechanisms of this enzyme, we investigated the effects of pH and salt concentration, deuterium isotope effect, steady-state kinetics, and rapid-phase ligand-binding kinetics. Enzyme activity was increased eightfold by the addition of 500 mM NaCl at pH 6.0, fourfold by 250 mM at pH 8.0, and became independent of salt concentration at pH 10.0. Full isotope effects observed at pH 10.0 under 0-1000 mM NaCl indicated that the rate of hydride transfer, which was the rate-determining step at the basic pH region, was independent of salt concentration. Conversely, rapid-phase ligand-binding experiments showed that the amplitude of the DHF-binding reaction increased and the tetrahydrofolate (THF)-releasing rate decreased with increasing NaCl concentration. These results suggested that the salt-activation mechanism of HjDHFR P1 is via the population change of the anion-unbound and anion-bound conformers, which are binding-incompetent and -competent conformations for DHF, respectively, while that of salt inactivation is via deceleration of the THF-releasing rate, which is the rate-determining step at the neutral pH region.

  2. Solid-state fermentation as a potential technique for esterase/lipase production by halophilic archaea.

    Science.gov (United States)

    Martin del Campo, Martha; Camacho, Rosa M; Mateos-Díaz, Juan C; Müller-Santos, Marcelo; Córdova, Jesus; Rodríguez, Jorge A

    2015-11-01

    Halophilic archaea are extremophiles, adapted to high-salt environments, showing a big biotechnological potential as enzyme, lipids and pigments producers. Four inert supports (perlite, vermiculite, polyurethane foam and glass fiber) were employed for solid-state fermentation (SSF) of the halophilic archaeon Natronococcus sp. TC6 to investigate biomass and esterase production. A very low esterase activity and high water activity were observed when perlite, vermiculite and polyurethane were used as supports. When glass fiber was employed, an important moisture loss was observed (8.6%). Moreover, moisture retention was improved by mixing polyurethane and glass fiber, resulting in maximal biomass and esterase production. Three halophilic archaea: Natronococcus sp. TC6, Halobacterium sp. NRC-1 and Haloarcula marismortui were cultured by submerged fermentation (SmF) and by SSF; an improvement of 1.3- to 6.2-fold was observed in the biomass and esterase production when SSF was used. Growth was not homogeneous in the mixture, but was predominant in the glass fiber thus was probably because the glass fiber provides a holder to the cells, while the polyurethane acts as an impregnation medium reservoir. To the best of our knowledge, this work is the first report on haloarchaea cultivation by SSF aiming biomass and esterase/lipase activity production.

  3. Effect of UVC Radiation on Hydrated and Desiccated Cultures of Slightly Halophilic and Non-Halophilic Methanogenic Archaea: Implications for Life on Mars.

    Science.gov (United States)

    Sinha, Navita; Kral, Timothy A

    2018-05-12

    Methanogens have been considered models for life on Mars for many years. In order to survive any exposure at the surface of Mars, methanogens would have to endure Martian UVC radiation. In this research, we irradiated hydrated and desiccated cultures of slightly halophilic Methanococcus maripaludis and non-halophilic Methanobacterium formicicum for various time intervals with UVC (254 nm) radiation. The survivability of the methanogens was determined by measuring methane concentrations in the headspace gas samples of culture tubes after re-inoculation of the methanogens into their growth-supporting media following exposure to UVC radiation. Hydrated M. maripaludis survived 24 h of UVC exposure, while in a desiccated condition they endured for 16 h. M. formicicum also survived UVC radiation for 24 h in a liquid state; however, in a desiccated condition, the survivability of M. formicicum was only 12 h. Some of the components of the growth media could have served as shielding agents that protected cells from damage caused by exposure to ultraviolet radiation. Overall, these results suggest that limited exposure (12⁻24 h) to UVC radiation on the surface of Mars would not necessarily be a limiting factor for the survivability of M. maripaludis and M. formicicum .

  4. Bioprospecting of lipolytic microorganisms obtained from industrial effluents

    Directory of Open Access Journals (Sweden)

    GREICE H.S. PEIL

    2016-01-01

    Full Text Available ABSTRACT The lipases have ability to catalyze diverse reactions and are important in different biotechnological applications. The aim of this work was to isolate and characterize microorganisms that produce lipases, from different food industry effluents localized in Pelotas, RS/Brazil. Bacteria were identified using Gram stain and biochemical tests (Vitek 2(r. Fungi were identified according to macro and micromorphology characteristics. The extracellular lipase production was evaluated using the Rhodamine B test and the enzymatic activity by titration. Twenty-one bacteria were isolated and identified as Klebsiella pneumoniae ssp. pneumoniae, Serratia marcescens, Enterobacter aerogenes, Raoultella ornithinolytica and Raoultella planticola. Were characterized isolated filamentous fungi by the following genera: Alternaria sp., Fusarium sp., Geotrichum sp., Gliocladium sp., Mucor sp., Paecilomyces sp. and Trichoderma sp. Extracellular lipase production was observed in 71.43% of the bacteria and 57.14% of the fungi. The bacterium that presented better promising enzymatic activity was E. aerogenes (1.54 U/ml however between fungi there was not significant difference between the four isolates. This study indicated that microorganisms lipase producers are present in the industrial effluents, as well as these enzymes have potential of biodegradation of lipid compounds.

  5. Bioprospecting of lipolytic microorganisms obtained from industrial effluents.

    Science.gov (United States)

    Peil, Greice H S; Kuss, Anelise V; Rave, Andrés F G; Villarreal, José P V; Hernandes, Yohana M L; Nascente, Patrícia S

    2016-01-01

    The lipases have ability to catalyze diverse reactions and are important in different biotechnological applications. The aim of this work was to isolate and characterize microorganisms that produce lipases, from different food industry effluents localized in Pelotas, RS/Brazil. Bacteria were identified using Gram stain and biochemical tests (Vitek 2(r)). Fungi were identified according to macro and micromorphology characteristics. The extracellular lipase production was evaluated using the Rhodamine B test and the enzymatic activity by titration. Twenty-one bacteria were isolated and identified as Klebsiella pneumoniae ssp. pneumoniae, Serratia marcescens, Enterobacter aerogenes, Raoultella ornithinolytica and Raoultella planticola. Were characterized isolated filamentous fungi by the following genera: Alternaria sp., Fusarium sp., Geotrichum sp., Gliocladium sp., Mucor sp., Paecilomyces sp. and Trichoderma sp. Extracellular lipase production was observed in 71.43% of the bacteria and 57.14% of the fungi. The bacterium that presented better promising enzymatic activity was E. aerogenes (1.54 U/ml) however between fungi there was not significant difference between the four isolates. This study indicated that microorganisms lipase producers are present in the industrial effluents, as well as these enzymes have potential of biodegradation of lipid compounds.

  6. Metabolic Capability of a Predominant Halanaerobium sp. in Hydraulically Fractured Gas Wells and Its Implication in Pipeline Corrosion

    Science.gov (United States)

    Liang, Renxing; Davidova, Irene A.; Marks, Christopher R.; Stamps, Blake W.; Harriman, Brian H.; Stevenson, Bradley S.; Duncan, Kathleen E.; Suflita, Joseph M.

    2016-01-01

    Microbial activity associated with produced water from hydraulic fracturing operations can lead to gas souring and corrosion of carbon-steel equipment. We examined the microbial ecology of produced water and the prospective role of the prevalent microorganisms in corrosion in a gas production field in the Barnett Shale. The microbial community was mainly composed of halophilic, sulfidogenic bacteria within the order Halanaerobiales, which reflected the geochemical conditions of highly saline water containing sulfur species (S2O32-, SO42-, and HS-). A predominant, halophilic bacterium (strain DL-01) was subsequently isolated and identified as belonging to the genus Halanaerobium. The isolate could degrade guar gum, a polysaccharide polymer used in fracture fluids, to produce acetate and sulfide in a 10% NaCl medium at 37°C when thiosulfate was available. To mitigate potential deleterious effects of sulfide and acetate, a quaternary ammonium compound was found to be an efficient biocide in inhibiting the growth and metabolic activity of strain DL-01 relative to glutaraldehyde and tetrakis (hydroxymethyl) phosphonium sulfate. Collectively, our findings suggest that predominant halophiles associated with unconventional shale gas extraction could proliferate and produce sulfide and acetate from the metabolism of polysaccharides used in hydraulic fracturing fluids. These metabolic products might be returned to the surface and transported in pipelines to cause pitting corrosion in downstream infrastructure. PMID:27446028

  7. COUNTS OF MICROORGANISMS CAUSING BOVINE MASTITIS AND STUDY OF ANTIMICROBIAL ACTION

    Directory of Open Access Journals (Sweden)

    Wanessa Oliveira Ribeiro

    2014-02-01

    Full Text Available Mastitis is an inflammation of the mammary gland caused mainly by microorganisms, altering the characteristics of milk and results in significant economic losses for this production complex. The study aimed to determine the main causative agents of bovine mastitis in a dairy farm in Rio Pomba city, Minas Gerais state, Brazil, and evaluate the use of plant extract and antibiotics commonly used in the control of microorganisms that cause this disease. Raw milk samples coming from 47 dairy cow were individually collected for microbiological evaluation. We also evaluated the sensitivity of isolates from the plant extract and the antibiotics commonly used in the farm. It was found that 17.0 %, 31.9 %, 85.4 % and 38.3 % of the samples presented, respectively, Staphylococcus aureus, coliforms, faecal coliforms and Escherichia coli. Furthermore, most of the samples showed counts of aerobic mesophilic microorganisms and Streptococcus sp. between 104 and 105 CFU.mL-1, while the counts of S. aureus ranged between 102 and 103 CFU.mL-1 in most of samples. A higher efficacy of tetracycline on the isolates of S. aureus was verified and of ampicillin on the E. coli isolates. All isolates of the latter bacteria were resistant to plant extract. Due to the high incidence of microorganisms, we emphasize the need for implementation of Good Agricultural Practices in milk production, because these bacteria are coming from hair, skin, mucous membranes of animals and/or belonging to the enteric microbiota of mammals, respectively.

  8. Dynamic structure mediates halophilic adaptation of a DNA polymerase from the deep-sea brines of the Red Sea.

    Science.gov (United States)

    Takahashi, Masateru; Takahashi, Etsuko; Joudeh, Luay I; Marini, Monica; Das, Gobind; Elshenawy, Mohamed M; Akal, Anastassja; Sakashita, Kosuke; Alam, Intikhab; Tehseen, Muhammad; Sobhy, Mohamed A; Stingl, Ulrich; Merzaban, Jasmeen S; Di Fabrizio, Enzo; Hamdan, Samir M

    2018-01-24

    The deep-sea brines of the Red Sea are remote and unexplored environments characterized by high temperatures, anoxic water, and elevated concentrations of salt and heavy metals. This environment provides a rare system to study the interplay between halophilic and thermophilic adaptation in biologic macromolecules. The present article reports the first DNA polymerase with halophilic and thermophilic features. Biochemical and structural analysis by Raman and circular dichroism spectroscopy showed that the charge distribution on the protein's surface mediates the structural balance between stability for thermal adaptation and flexibility for counteracting the salt-induced rigid and nonfunctional hydrophobic packing. Salt bridge interactions via increased negative and positive charges contribute to structural stability. Salt tolerance, conversely, is mediated by a dynamic structure that becomes more fixed and functional with increasing salt concentration. We propose that repulsive forces among excess negative charges, in addition to a high percentage of negatively charged random coils, mediate this structural dynamism. This knowledge enabled us to engineer a halophilic version of KOD DNA polymerase.-Takahashi, M., Takahashi, E., Joudeh, L. I., Marini, M., Das, G., Elshenawy, M. M., Akal, A., Sakashita, K., Alam, I., Tehseen, M., Sobhy, M. A., Stingl, U., Merzaban, J. S., Di Fabrizio, E., Hamdan, S. M. Dynamic structure mediates halophilic adaptation of a DNA polymerase from the deep-sea brines of the Red Sea.

  9. Dynamic structure mediates halophilic adaptation of a DNA polymerase from the deep-sea brines of the Red Sea

    KAUST Repository

    Takahashi, Masateru; Takahashi, Etsuko; Joudeh, Luay I.; Marini, Monica; Das, Gobind; Elshenawy, Mohamed; Akal, Anastassja; Sakashita, Kosuke; Alam, Intikhab; Tehseen, Muhammad; Sobhy, Mohamed Abdelmaboud; Stingl, Ulrich; Merzaban, Jasmeen; Di Fabrizio, Enzo M.; Hamdan, Samir

    2018-01-01

    The deep-sea brines of the Red Sea are remote and unexplored environments characterized by high temperatures, anoxic water, and elevated concentrations of salt and heavy metals. This environment provides a rare system to study the interplay between halophilic and thermophilic adaptation in biologic macromolecules. The present article reports the first DNA polymerase with halophilic and thermophilic features. Biochemical and structural analysis by Raman and circular dichroism spectroscopy showed that the charge distribution on the protein’s surface mediates the structural balance between stability for thermal adaptation and flexibility for counteracting the salt-induced rigid and nonfunctional hydrophobic packing. Salt bridge interactions via increased negative and positive charges contribute to structural stability. Salt tolerance, conversely, is mediated by a dynamic structure that becomes more fixed and functional with increasing salt concentration. We propose that repulsive forces among excess negative charges, in addition to a high percentage of negatively charged random coils, mediate this structural dynamism. This knowledge enabled us to engineer a halophilic version of KOD DNA polymerase.—Takahashi, M., Takahashi, E., Joudeh, L. I., Marini, M., Das, G., Elshenawy, M. M., Akal, A., Sakashita, K., Alam, I., Tehseen, M., Sobhy, M. A., Stingl, U., Merzaban, J. S., Di Fabrizio, E., Hamdan, S. M. Dynamic structure mediates halophilic adaptation of a DNA polymerase from the deep-sea brines of the Red Sea.

  10. Dynamic structure mediates halophilic adaptation of a DNA polymerase from the deep-sea brines of the Red Sea

    KAUST Repository

    Takahashi, Masateru

    2018-01-24

    The deep-sea brines of the Red Sea are remote and unexplored environments characterized by high temperatures, anoxic water, and elevated concentrations of salt and heavy metals. This environment provides a rare system to study the interplay between halophilic and thermophilic adaptation in biologic macromolecules. The present article reports the first DNA polymerase with halophilic and thermophilic features. Biochemical and structural analysis by Raman and circular dichroism spectroscopy showed that the charge distribution on the protein’s surface mediates the structural balance between stability for thermal adaptation and flexibility for counteracting the salt-induced rigid and nonfunctional hydrophobic packing. Salt bridge interactions via increased negative and positive charges contribute to structural stability. Salt tolerance, conversely, is mediated by a dynamic structure that becomes more fixed and functional with increasing salt concentration. We propose that repulsive forces among excess negative charges, in addition to a high percentage of negatively charged random coils, mediate this structural dynamism. This knowledge enabled us to engineer a halophilic version of KOD DNA polymerase.—Takahashi, M., Takahashi, E., Joudeh, L. I., Marini, M., Das, G., Elshenawy, M. M., Akal, A., Sakashita, K., Alam, I., Tehseen, M., Sobhy, M. A., Stingl, U., Merzaban, J. S., Di Fabrizio, E., Hamdan, S. M. Dynamic structure mediates halophilic adaptation of a DNA polymerase from the deep-sea brines of the Red Sea.

  11. Biosurfactants Produced by Marine Microorganisms with Therapeutic Applications.

    Science.gov (United States)

    Gudiña, Eduardo J; Teixeira, José A; Rodrigues, Lígia R

    2016-02-18

    Marine microorganisms possess unique metabolic and physiological features and are an important source of new biomolecules, such as biosurfactants. Some of these surface-active compounds synthesized by marine microorganisms exhibit antimicrobial, anti-adhesive and anti-biofilm activity against a broad spectrum of human pathogens (including multi-drug resistant pathogens), and could be used instead of existing drugs to treat infections caused by them. In other cases, these biosurfactants show anti-cancer activity, which could be envisaged as an alternative to conventional therapies. However, marine biosurfactants have not been widely explored, mainly due to the difficulties associated with the isolation and growth of their producing microorganisms. Culture-independent techniques (metagenomics) constitute a promising approach to study the genetic resources of otherwise inaccessible marine microorganisms without the requirement of culturing them, and can contribute to the discovery of novel biosurfactants with significant biological activities. This paper reviews the most relevant biosurfactants produced by marine microorganisms with potential therapeutic applications and discusses future perspectives and opportunities to discover novel molecules from marine environments.

  12. Biosurfactants Produced by Marine Microorganisms with Therapeutic Applications

    Directory of Open Access Journals (Sweden)

    Eduardo J. Gudiña

    2016-02-01

    Full Text Available Marine microorganisms possess unique metabolic and physiological features and are an important source of new biomolecules, such as biosurfactants. Some of these surface-active compounds synthesized by marine microorganisms exhibit antimicrobial, anti-adhesive and anti-biofilm activity against a broad spectrum of human pathogens (including multi-drug resistant pathogens, and could be used instead of existing drugs to treat infections caused by them. In other cases, these biosurfactants show anti-cancer activity, which could be envisaged as an alternative to conventional therapies. However, marine biosurfactants have not been widely explored, mainly due to the difficulties associated with the isolation and growth of their producing microorganisms. Culture-independent techniques (metagenomics constitute a promising approach to study the genetic resources of otherwise inaccessible marine microorganisms without the requirement of culturing them, and can contribute to the discovery of novel biosurfactants with significant biological activities. This paper reviews the most relevant biosurfactants produced by marine microorganisms with potential therapeutic applications and discusses future perspectives and opportunities to discover novel molecules from marine environments.

  13. Metabolic flux analysis of the halophilic archaeon Haladaptatus paucihalophilus.

    Science.gov (United States)

    Liu, Guangxiu; Zhang, Manxiao; Mo, Tianlu; He, Lian; Zhang, Wei; Yu, Yi; Zhang, Qi; Ding, Wei

    2015-11-27

    This work reports the (13)C-assisted metabolic flux analysis of Haladaptatus paucihalophilus, a halophilic archaeon possessing an intriguing osmoadaption mechanism. We showed that the carbon flow is through the oxidative tricarboxylic acid (TCA) cycle whereas the reductive TCA cycle is not operative in H. paucihalophilus. In addition, both threonine and the citramalate pathways contribute to isoleucine biosynthesis, whereas lysine is synthesized through the diaminopimelate pathway and not through the α-aminoadipate pathway. Unexpected, the labeling patterns of glycine from the cells grown on [1-(13)C]pyruvate and [2-(13)C]pyruvate suggest that, unlike all the organisms investigated so far, in which glycine is produced exclusively from the serine hydroxymethyltransferase (SHMT) pathway, glycine biosynthesis in H. paucihalophilus involves different pathways including SHMT, threonine aldolase (TA) and the reverse reaction of glycine cleavage system (GCS), demonstrating for the first time that other pathways instead of SHMT can also make a significant contribution to the cellular glycine pool. Transcriptional analysis confirmed that both TA and GCS genes were transcribed in H. paucihalophilus, and the transcriptional level is independent of salt concentrations in the culture media. This study expands our understanding of amino acid biosynthesis and provides valuable insights into the metabolism of halophilic archaea. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Microorganisms present on peripheral intravenous needleless connectors in the clinical environment.

    Science.gov (United States)

    Slater, Karen; Cooke, Marie; Whitby, Michael; Fullerton, Fiona; Douglas, Joel; Hay, Jennine; Rickard, Claire

    2017-08-01

    The aim of this study was to quantify culturable microorganisms on needleless connectors (NCs) attached to peripheral intravenous catheters in hospitalized adult medical patients. Half (50%) of 40 NCs were contaminated with microorganisms commonly found on the skin or mouth. Staphylococcus capitis and Staphylococcus epidermidis were most commonly isolated. Emergency department insertion and higher patient dependency were statistically associated with positive NC microorganism growth. These results reaffirm the need for NC decontamination prior to access. Crown Copyright © 2017. Published by Elsevier Inc. All rights reserved.

  15. False identification of other microorganisms as Staphylococcus ...

    African Journals Online (AJOL)

    Methods: 507 microorganisms which have been previously identified as S. aureus in 8 States in Southern Nigeria through characteristic morphology on blood agar, Gram staining, growth and fermentation on Mannitol Salt Agar and coagulase formation were collected. All the isolates were identified in this study through ...

  16. [Comparative analysis of clustered regularly interspaced short palindromic repeats (CRISPRs) loci in the genomes of halophilic archaea].

    Science.gov (United States)

    Zhang, Fan; Zhang, Bing; Xiang, Hua; Hu, Songnian

    2009-11-01

    Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) is a widespread system that provides acquired resistance against phages in bacteria and archaea. Here we aim to genome-widely analyze the CRISPR in extreme halophilic archaea, of which the whole genome sequences are available at present time. We used bioinformatics methods including alignment, conservation analysis, GC content and RNA structure prediction to analyze the CRISPR structures of 7 haloarchaeal genomes. We identified the CRISPR structures in 5 halophilic archaea and revealed a conserved palindromic motif in the flanking regions of these CRISPR structures. In addition, we found that the repeat sequences of large CRISPR structures in halophilic archaea were greatly conserved, and two types of predicted RNA secondary structures derived from the repeat sequences were likely determined by the fourth base of the repeat sequence. Our results support the proposal that the leader sequence may function as recognition site by having palindromic structures in flanking regions, and the stem-loop secondary structure formed by repeat sequences may function in mediating the interaction between foreign genetic elements and CAS-encoded proteins.

  17. Isolation and identification of culturable extremely halophilic archaea of Inche-Boroun wetland

    Directory of Open Access Journals (Sweden)

    Mehrnoosh Rasooli

    2013-11-01

    Full Text Available Haloarchaeal diversity of Inche-Boroun wetland in north of Iran in Golestan province was investigated by using culture-dependent methods. Sampling was carried out in May and September 2010. In each sampling, 4 distinct region of wetland were analyzed by using complex media like MGM, JCM168, MH1 and an alkaliphilic medium containing 23% salts. After incubation at 40ºC, a total of 406 isolates were prepared and 2.1×106 CFU/ml were obtained in culture media. Among all isolates, 361 isolates were obtained from MGM and 39 isolates from JCM 168, 3 isolates from MH1 and 3 isolate from alkaliphilic media. Initial morphological, biochemical and physiological tests were performed. According to the results, 45 isolates were selected and phylogenetic analysis of 16S rRNA was performed for them. Among selected strains, 40 isolates belonged to Halobacteriacaea and were related to Haloarcula, Halorubrum, Haloferax, Halobellus, Halogeometricum, Halobacterium, Halolamina, Halorhabdus and Halostagnicola (respectively 30, 27.5, 17.5, 10, 5.2, 2.6, 2.6, 2.6 and 2.6 percent of Haloarchaeal strains. A total of 5 strains belonged to the kingdom of Bacteria and were related to Rhodovibrio, Pseudomonas and Salicola (respectively 40, 40 and 20 percent of bacterial strains. According to our results and the limited numbers of haloarchaeal genera that having been discovered until now, it seemed that the culturable prokaryotic populations in this hypersaline environment was diverse.

  18. Alleviation of salt stress by halotolerant and halophilic plant growth-promoting bacteria in wheat (Triticum aestivum

    Directory of Open Access Journals (Sweden)

    Furkan Orhan

    Full Text Available ABSTRACT In the current study, 18 halotolerant and halophilic bacteria have been investigated for their plant growth promoting abilities in vitro and in a hydroponic culture. The bacterial strains have been investigated for ammonia, indole-3-acetic acid and 1-aminocyclopropane-1-carboxylate-deaminase production, phosphate solubilisation and nitrogen fixation activities. Of the tested bacteria, eight were inoculated with Triticum aestivum in a hydroponic culture. The investigated bacterial strains were found to have different plant-growth promoting activities in vitro. Under salt stress (200 mM NaCl, the investigated bacterial strains significantly increased the root and shoot length and total fresh weight of the plants. The growth rates of the plants inoculated with bacterial strains ranged from 62.2% to 78.1%.Identifying of novel halophilic and halotolerant bacteria that promote plant growth can be used as alternatives for salt sensitive plants. Extensive research has been conducted on several halophilic and halotolerant bacterial strains to investigate their plant growth promoting activities. However, to the best of my knowledge, this is the first study to inoculate these bacterial strains with wheat.

  19. Alleviation of salt stress by halotolerant and halophilic plant growth-promoting bacteria in wheat (Triticum aestivum).

    Science.gov (United States)

    Orhan, Furkan

    2016-01-01

    In the current study, 18 halotolerant and halophilic bacteria have been investigated for their plant growth promoting abilities in vitro and in a hydroponic culture. The bacterial strains have been investigated for ammonia, indole-3-acetic acid and 1-aminocyclopropane-1-carboxylate-deaminase production, phosphate solubilisation and nitrogen fixation activities. Of the tested bacteria, eight were inoculated with Triticum aestivum in a hydroponic culture. The investigated bacterial strains were found to have different plant-growth promoting activities in vitro. Under salt stress (200mM NaCl), the investigated bacterial strains significantly increased the root and shoot length and total fresh weight of the plants. The growth rates of the plants inoculated with bacterial strains ranged from 62.2% to 78.1%. Identifying of novel halophilic and halotolerant bacteria that promote plant growth can be used as alternatives for salt sensitive plants. Extensive research has been conducted on several halophilic and halotolerant bacterial strains to investigate their plant growth promoting activities. However, to the best of my knowledge, this is the first study to inoculate these bacterial strains with wheat. Copyright © 2016 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

  20. Ribulose 1,5-bisphosphate dependent CO2 fixation in the halophilic archaebacterium, Halobacterium mediterranei

    International Nuclear Information System (INIS)

    Rawal, N.; Kelkar, S.M.; Altekar, W.

    1988-01-01

    The cell extract of Halobacterium mediterranei catalyses incorporation of 14 CO 2 into 3-phosphoglycerate in the presence of ribulose bisphosphate suggesting the existence of ribulose bisphosphate carboxylase activity in this halophilic archaebacterium

  1. Halophilic-Psychrophilic Bacteria from Tirich Mir Glacier, Pakistan, as Potential Candidate for Astrobiological Studies

    Science.gov (United States)

    Rafiq, M. R.; Anesio, A. M. A.; Hayat, M. H.; Zada, S. Z.; Sajjad, W. S.; Shah, A. A. S.; Hasan, F. H.

    2016-09-01

    Hindu Kush, Karakoram, and Himalaya region is referred to as 'third pole' and could be suitable as a terrestrial analog of Mars and increased possibility of finding polyextremophiles. Study is focused on halophilic psychrophiles.

  2. Surfactant producing TNT-degrading microorganisms for bioremediation

    Energy Technology Data Exchange (ETDEWEB)

    Vorobyov, A.; Marchenko, A.; Rudneva, O.; Borovick, R. [Research Center for Toxicology and Hygienic Regulation of Biopreparations, Serpukhov, Moscow region (Russian Federation); Radosevich, M. [Univ. of Delaware, Newark (United States). Dept. of Plant and Soil Sciences

    2003-07-01

    In general the biodegradation of nitroaromatic hydrocarbons is influenced by their bioavailability. 2,4,6-trinitrotoluene is very poorly soluble in water. TNT is easily adsorbed to clay or humus fractions in the soil, and pass very slowly to the aqueous phase, where microorganisms metabolize it. Biosurfactants that increase TNT solubility and improve its bioavailability can thereby accelerate degradation. Pure cultures of microorganisms-TNT degraders were isolated by the method of enrichment cultures from samples of different-type soil contaminated by TNT (soddy-podzol, black earth, and gray forest ones). From 28 soil samples 35 isolates of microorganisms degrading TNT were taken. The isolated soil samples had been tested for availability of microbial activity towards TNT. By10 g of air-dried soil, 10 ml of distilled water, and 2 mg of TNT were placed into 750 ml shaken flasks. The flasks were incubated at 150 rev/min and 24 C. Glucose, sodium succinate or sodium acetate had been used as co-substrates. The ability of the strains to produce surfactants was studied by drop collapsing test and direct measuring of surface tension of cultural liquid after cultivation with TNT. Cells of the strains were cultivated on solid and liquid nutrient media. For drop collapsing test the cells were cultivated on solid nutrient media; the separated colonies were suspended in distilled water. Drop sustainability test ws conducted on a standard 96-well plates coated with a thin layer of vaseline oil. Surface tension of cultural liquid ws measured after cultivation of strains in the presence of TNT with the use of a ring tensiometer. Before measuring of surface tension microbial cells were collected from liquid culture by centrifugation. (orig.)

  3. Characterization of the promising poly(3-hydroxybutyrate) producing halophilic bacterium Halomonas halophila

    Czech Academy of Sciences Publication Activity Database

    Kučera, D.; Pernicová, I.; Kovalčik, A.; Koller, M.; Müllerová, L.; Sedláček, P.; Mravec, F.; Nebesářová, Jana; Kalina, M.; Márová, I.; Krzyžánek, Vladislav; Obruča, S.

    2018-01-01

    Roč. 256, May (2018), s. 552-556 ISSN 0960-8524 R&D Projects: GA MŠk(CZ) LM2015062; GA ČR(CZ) GA15-20645S Institutional support: RVO:68081731 Keywords : Halomonas halophila * halophiles * lignocellulose hydrolysates * morphology of bacterial cells * polyhydroxyalkanoates Impact factor: 5.651, year: 2016

  4. Bacterioruberin and salinixanthin carotenoids of extremely halophilic Archaea and Bacteria: A Raman spectroscopic study

    Science.gov (United States)

    Jehlička, J.; Edwards, H. G. M.; Oren, A.

    2013-04-01

    Laboratory cultures of a number of red extremely halophilic Archaea (Halobacterium salinarum strains NRC-1 and R1, Halorubrum sodomense, Haloarcula valismortis) and of Salinibacter ruber, a red extremely halophilic member of the Bacteria, have been investigated by Raman spectroscopy using 514.5 nm excitation to characterize their carotenoids. The 50-carbon carotenoid α-bacterioruberin was detected as the major carotenoid in all archaeal strains. Raman spectroscopy also detected bacterioruberin as the main pigment in a red pellet of cells collected from a saltern crystallizer pond. Salinibacter contains the C40-carotenoid acyl glycoside salinixanthin (all-E, 2'S)-2'-hydroxy-1'-[6-O-(methyltetradecanoyl)-β-D-glycopyranosyloxy]-3',4'-didehydro-1',2'-dihydro-β,ψ-carotene-4-one), for which the Raman bands assignments of are given here for the first time.

  5. Formation of harmful compounds in biotransformation of lilial by microorganisms isolated from human skin.

    Science.gov (United States)

    Esmaeili, Akbar; Afshari, Shima; Esmaeili, Davood

    2015-01-01

    The biotransformation of lilial results in an acid that is used in the dairy industry, in perfumery, as an intermediate in the manufacture of pharmaceuticals and cosmetics, and as a food additive for enhancing taste. This study investigates the biotransformation of lilial by Staphylococcus aureus and Staphylococcus epidermidis, two bacterial species isolated from human skin. Both species of Staphylococcus were isolated in samples taken from the skin of individuals living in a rural area of Iran. The pH of the culture medium was optimized, and after culturing the microorganisms, the bacteria were added to a flask containing a nutrient broth and incubated for several hours. The flasks of bacteria were combined with lilial, and various biochemical tests and diagnostics were performed, including Fourier transform infrared spectroscopy (FT-IR), ultraviolet-visible spectrophotometry (UV-Vis), and gas chromatography-mass spectroscopy (GC-MS). The S. aureus produced isobutyric acid (2-methylpropanoic acid) after 72 h (71% of the total products yielded during biotransformation), whereas the S. epidermidis produced terpenoid alcoholic media after 24 h (90% of total products obtained). The results obtained indicate that biotransformation of lilial by S. aureus is more desirable than by S. epidermidis due to the highly efficient production of a single product. Bourgeonal and liliol were two toxic compounds produced during biotransformation, which indicates that the use of lilial in cosmetics can be harmful to the skin.

  6. Ruegeria profundi sp. nov. and Ruegeria marisrubri sp. nov., isolated from the brine–seawater interface at Erba Deep in the Red Sea

    KAUST Repository

    Zhang, Guishan; Haroon, Mohamed; Zhang, Ruifu; Dong, Xiaoyan; Wang, Dandan; Liu, Yunpeng; Xun, Weibing; Dong, Xiuzhu; Stingl, Ulrich

    2017-01-01

    Two moderately halophilic marine bacterial strains of the family Rhodobacteraceae, designated ZGT108T and ZGT118T, were isolated from the brine-seawater interface at Erba Deep in the Red Sea (Saudi Arabia). Cells of both strains were aerobic, rod

  7. Screening and characterization of useful microorganisms to arsenic removal

    OpenAIRE

    宮武, 宗利; 林, 幸男

    2007-01-01

    Microorganisms were isolated from soil and their arsenic removal abilities were evaluated. Seven out of the 100 isolated strains showed more than 20% arsenic removal. Time courses of arsenic removal and cell growth were investigated in three of these isolated strains. Although the growth rates were different, the dependence of arsenic removal on cell growth was similar in three strains (A-84, 88, 89). Strain A-89 showed highest arsenic removal rate of 63% after first day. Strain A-88 was best...

  8. Producing Biosurfactants from Purified Microorganisms Obtained from Oil-contaminated Soil

    Directory of Open Access Journals (Sweden)

    Nader Mokhtarian

    2010-09-01

    Full Text Available Contamination of soil by crude oil can pose serious problems to ecosystems. Soil washing by solutions containing biosurfactants is one of the most efficient methods for the remediation of contaminated soil by crude oil because it removes not only the crude oil but also heavy metals. In this study, five soil samples were taken from fields exposed to oil compounds over the years in order to produce biosurfactants from microorganisms that were capable of degrading oil compounds. Sixteen such microorganisms were isolated. After cultivation, their emulsification strength was examined using E24 test. From among the experimental microorganisms, a gram-negative and rod-shape microorganism called A-12 showed the greatest value of the E24 test index (36%. For each liter of the culture medium containing 365 mg of microorganisms, 3 gr of the biosurfactant compound was produced and separated as dried powder. The purified biosurfactant was used in the soil washing process. Also, the insulated microorganisms were capable of degrading crude oil floating on wastewaters.

  9. Surface Disinfectants for Burn Units Evaluated by a New Double Method, Using Microorganisms Recently Isolated From Patients, on a Surface Germ-Carrier Model.

    Science.gov (United States)

    Herruzo, Rafael; Vizcaino, Maria Jose; Herruzo, Irene; Sanchez, Manuel

    Assessment methods of surface disinfection based on international standards (Environmental Protection Agency, European Norms, etc) do not correspond to hospital reality. New evaluation methods of surfaces disinfection are proposed to choose the most suitable disinfectant to act against clinically relevant microorganisms detected on the surfaces of burn units. 1) "Immediate effect": 6 products were compared using a glass germ-carrier and 20 recently isolated microorganisms from different patients in the intensive care units. Disinfectants were applied with microfiber cloths. Log10 reductions were calculated for colony forming units produced after 15 minutes of disinfectant application. 2) "Residual effect": the glass germ-carriers were previously impregnated with one of the studied disinfectants. After a 30-minute wait period, they were then contaminated with 1 microorganism (from the 20 above-mentioned). After 15 minutes, the disinfectant was inhibited and the log10 reduction of colony forming units was assessed. The immediate effect (disinfection and microorganism dragging and transferring from the surface to the cloth) produced complete elimination of the inoculums for all products used except one (a diluted quaternary ammonium). The average residual effect found on the 20 microorganisms was moderate: 2 to 3 log10 colony forming unit reduction with chlorine dioxide or 0.5% chlorhexidine (and lower with the other products), obtaining surfaces refractory to recontamination, at least, during 30 minutes. Two tests should be performed before advising surface disinfectant: 1) direct effect and 2) residual efficacy. These characteristics should be considered when a new surface disinfectant is chosen. Chlorine dioxide has a similar or better direct effect than sodium hypochlorite and a similar residual effect than chlorhexidine.

  10. Screening of biosurfactants from cloud microorganisms

    Science.gov (United States)

    Sancelme, Martine; Canet, Isabelle; Traikia, Mounir; Uhliarikova, Yveta; Capek, Peter; Matulova, Maria; Delort, Anne-Marie; Amato, Pierre

    2015-04-01

    The formation of cloud droplets from aerosol particles in the atmosphere is still not well understood and a main source of uncertainties in the climate budget today. One of the principal parameters in these processes is the surface tension of atmospheric particles, which can be strongly affected by trace compounds called surfactants. Within a project devoted to bring information on atmospheric surfactants and their effects on cloud droplet formation, we focused on surfactants produced by microorganisms present in atmospheric waters. From our unique collection of microorganisms, isolated from cloud water collected at the Puy-de-Dôme (France),1 we undertook a screening of this bank for biosurfactant producers. After extraction of the supernatants of the pure cultures, surface tension of crude extracts was determined by the hanging drop technique. Results showed that a wide variety of microorganisms are able to produce biosurfactants, some of them exhibiting strong surfactant properties as the resulting tension surface decreases to values less then 35 mN.m-1. Preliminary analytical characterization of biosurfactants, obtained after isolation from overproducing cultures of Rhodococcus sp. and Pseudomonas sp., allowed us to identify them as belonging to two main classes, namely glycolipids and glycopeptides. 1. Vaïtilingom, M.; Attard, E.; Gaiani, N.; Sancelme, M.; Deguillaume, L.; Flossmann, A. I.; Amato, P.; Delort, A. M. Long-term features of cloud microbiology at the puy de Dôme (France). Atmos. Environ. 2012, 56, 88-100. Acknowledgements: This work is supported by the French-USA ANR SONATA program and the French-Slovakia programs Stefanik and CNRS exchange.

  11. Halomonas titanicae sp. nov., a halophilic bacterium isolated from the RMS Titanic.

    Science.gov (United States)

    Sánchez-Porro, Cristina; Kaur, Bhavleen; Mann, Henrietta; Ventosa, Antonio

    2010-12-01

    A Gram-negative, heterotrophic, aerobic, non-endospore-forming, peritrichously flagellated and motile bacterial strain, designated BH1(T), was isolated from samples of rusticles, which are formed in part by a consortium of micro-organisms, collected from the RMS Titanic wreck site. The strain grew optimally at 30-37°C, pH 7.0-7.5 and in the presence of 2-8 % (w/v) NaCl. We carried out a polyphasic taxonomic study in order to characterize the strain in detail. Phylogenetic analyses based on 16S rRNA gene sequence comparison indicated that strain BH1(T) clustered within the branch consisting of species of Halomonas. The most closely related type strains were Halomonas neptunia (98.6 % 16S rRNA sequence similarity), Halomonas variabilis (98.4 %), Halomonas boliviensis (98.3 %) and Halomonas sulfidaeris (97.5 %). Other closely related species were Halomonas alkaliphila (96.5 % sequence similarity), Halomonas hydrothermalis (96.3 %), Halomonas gomseomensis (96.3 %), Halomonas venusta (96.3 %) and Halomonas meridiana (96.2 %). The major fatty acids of strain BH1(T) were C(18 : 1)ω7c (36.3 %), C(16 : 0) (18.4 %) and C(19 : 0) cyclo ω8c (17.9 %). The DNA G+C content was 60.0 mol% (T(m)). Ubiquinone 9 (Q-9) was the major lipoquinone. The phenotypic features, fatty acid profile and DNA G+C content further supported the placement of strain BH1(T) in the genus Halomonas. DNA-DNA hybridization values between strain BH1(T) and H. neptunia CECT 5815(T), H. variabilis DSM 3051(T), H. boliviensis DSM 15516(T) and H. sulfidaeris CECT 5817(T) were 19, 17, 30 and 29 %, respectively, supporting the differential taxonomic status of BH1(T). On the basis of the phenotypic, chemotaxonomic and phylogenetic data, strain BH1(T) is considered to represent a novel species, for which the name Halomonas titanicae sp. nov. is proposed. The type strain is BH1(T) (=ATCC BAA-1257(T) =CECT 7585(T) =JCM 16411(T) =LMG 25388(T)).

  12. Anti-methicillin Resistant Staphylococcus aureus Compound Isolation from Halophilic Bacillus amyloliquefaciens MHB1 and Determination of Its Mode of Action Using Electron Microscope and Flow Cytometry Analysis

    OpenAIRE

    Jeyanthi, Venkadapathi; Velusamy, Palaniyandi

    2016-01-01

    The aim of this study was to purify, characterize and evaluate the antibacterial activity of bioactive compound against methicillin-resistant Staphylococcus aureus (MRSA). The anti-MRSA compound was produced by a halophilic bacterial strain designated as MHB1. The MHB1 strain exhibited 99��% similarity to Bacillus amyloliquefaciens based on 16S rRNA gene analysis. The culture conditions of Bacillus amyloliquefaciens MHB1 were optimized using nutritional and environmental parameters for enhanc...

  13. Transcription-coupled repair of UV damage in the halophilic archaea.

    Science.gov (United States)

    Stantial, Nicole; Dumpe, Jarrod; Pietrosimone, Kathryn; Baltazar, Felicia; Crowley, David J

    2016-05-01

    Transcription-coupled repair (TCR) is a subpathway of nucleotide excision repair (NER) in which excision repair proteins are targeted to RNA polymerase-arresting lesions located in the transcribed strand of active genes. TCR has been documented in a variety of bacterial and eukaryotic organisms but has yet to be observed in the Archaea. We used Halobacterium sp. NRC-1 and Haloferax volcanii to determine if TCR occurs in the halophilic archaea. Following UV irradiation of exponentially growing cultures, we quantified the rate of repair of cyclobutane pyrimidine dimers in the two strands of the rpoB2B1A1A2 and the trpDFEG operons of Halobacterium sp. NRC-1 and the pts operon of H. volcanii through the use of a Southern blot assay and strand-specific probes. TCR was observed in all three operons and was dependent on the NER gene uvrA in Halobacterium sp. NRC-1, but not in H. volcanii. The halophilic archaea likely employ a novel mechanism for TCR in which an as yet unknown coupling factor recognizes the arrested archaeal RNA polymerase complex and recruits certain NER proteins to complete the process. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Monitoring of opportunistic and pathogenic microorganisms in surgical departments of Dniprodzerzhynsk

    Directory of Open Access Journals (Sweden)

    N. N. Donets

    2013-03-01

    Full Text Available The paper presents monitoring results of the spread of opportunistic and pathogenic microorganisms in patients of surgical departments of the Dniprodzerzhynsk city hospital No 7. 1464 strains of bacteria isolated from biological material of the patients from January to December 2012 were studied. Relevant standard methods of research and data interpretation in accordance with the regulatory guidelines were used. The microorganisms’ sensitivity to antibiotics was determined by the disk diffusion method. Assessment of the resistance of isolated microorganisms to antibiotics was made with the software Whonet 5.1. At the first stage of investigation sampling biological material and inoculation in the culture medium were made. The discharges of wounds, throat, nose, ears, vagina and urethra, and also urine from patients of surgical departments were sampled for bacteriological analysis. The main substratum was 5% blood agar. There may additionally be used the selective growth media (yolk-salt agar, Endo, and Saburo. At the second stage we identify microorganisms with bacterioscopic, bacteriological and biochemical methods. Identifying microorganisms of the genus Staphylococcus was made by the reaction of lecithinase presence, plasma-coagulation reaction and the mannitol oxidation reaction. For the identification of bacteria of the family Streptococcaceae the growth pattern in 0.5% sugar medium was used. It was differentiated from bacteria of the genus Enterococcus by plating onto egg yolk agar base and milk with 0.1% methylene blue. Identification of bacteria of the Enterobacteriaceae family was made by studying their colonies on dense differential diagnostic media. Suspicious colonies were transferred on a combined medium for primary identification (Olkenitsky's medium. Then the biochemical signs of enterobacteria were studied in the minimum number of tests. The third phase of the study included the determination of the sensitivity of

  15. Survival of Halophilic Archaea in the Stratosphere as a Mars Analog: A Transcriptomic Approach

    Science.gov (United States)

    DasSarma, S.; DasSarma, P.; Laye, V.; Harvey, J.; Reid, C.; Shultz, J.; Yarborough, A.; Lamb, A.; Koske-Phillips, A.; Herbst, A.; Molina, F.; Grah, O.; Phillips, T.

    2016-05-01

    On Earth, halophilic Archaea tolerate multiple extreme conditions similar to those on Mars. In order to study their survival, we launched live cultures into Earth’s stratosphere on helium balloons. The effects on survival and transcriptomes were interrogated in the lab.

  16. Interaction of Extreme Halophilic Archaea With the Evaporites of the Solar Salterns Guerrero Negro Baja California, Mexico

    Science.gov (United States)

    Tamez, P.; Lopez-Cortés, A.

    2008-12-01

    Hypersaline environments have been significant reservoirs for the long-term evolution of specifically adapted microorganisms. Characterized to have higher salt concentrations (up to 35 g/L), they are worldwide distributed and have a commercial significance. Exportadora de Sal, Guerrero Negro, Mexico has a multipond salterns system designed to harvest common salt (NaCl) from sea water. To achieve this purpose, sea water is pumped through a set of shallow ponds where water evaporates and salts concentrate. Sequential precipitation of CaCO3, CaSO4 2H2O and NaCl occurs in a mineral formations call it evaporites. In the interior of those gypsum-encrusted and halite-encrusted minerals, communities of extremely salt-loving archaea prosper. Previous studies have showed the influence of Haloarchaeal cells in the formation of larger fluid inclusions than crystals formed in sterile salt solutions. S-layer envelopes and cells of Haloarcula strain SP8807 contributed to the nucleation of new crystals of NaCl. Given the significance of the scope in phylogenetic archaeal diversity research, this study had a polyphasic approach. SEM micrographs from a 21- 31% (w/v) gradient salt multipond system evaporites, gave an insight profile of the extreme halophilic archaeal communities thriving in the surface of the gypsum and halite evaporites. Halite crystals were form after 21 days of incubation in solid medium with archaeal cells. Both culture and non-culture dependent methods, Nested-PCR-DGGE analysis and sequencing of 16S rDNA amplified fragment genes from environmental samples and isolated strains were used for this purpose. We isolate three strains from Pond 9 (21.07% total salt concentration) and one strain from Cristallizer 20 (25.15% total salt concentration). 16S rDNA signaling gave 99% of similarity with Halogeometricum borinquense, sequence AF002984, two other strains were 99% of similarity with Halobacterium salinarum, sequence AJ496185 these strains shown different colony

  17. A Comprehensive Characterization of Microorganisms and Allergens in Spacecraft Environment

    Science.gov (United States)

    Castro, V.A.; Ott, C.M.; Garcia, V.M.; John, J.; Buttner, M.P.; Cruz, P.; Pierson, D.L.

    2009-01-01

    The determination of risk from infectious disease during long-duration missions is composed of several factors including the concentration and the characteristics of the infectious agent. Thus, a thorough knowledge of the microorganisms aboard spacecraft is essential in mitigating infectious disease risk to the crew. While stringent steps are taken to minimize the transfer of potential pathogens to spacecraft, several medically significant organisms have been isolated from both the Mir and International Space Station (ISS). Historically, the method for isolation and identification of microorganisms from spacecraft environmental samples depended upon their growth on culture media. Unfortunately, only a fraction of the organisms may grow on a culture medium, potentially omitting those microorganisms whose nutritional and physical requirements for growth are not met. Thus, several pathogens may not have been detected, such as Legionella pneumophila, the etiological agent of Legionnaire s disease. We hypothesize that environmental analysis using non-culture-based technologies will reveal microorganisms, allergens, and microbial toxins not previously reported in spacecraft, allowing for a more complete health assessment. The development of techniques for this flight experiment, operationally named SWAB, has already provided advances in NASA laboratory processes and beneficial information toward human health risk assessment. The translation of 16S ribosomal DNA sequencing for the identification of bacteria from the SWAB experiment to nominal operations has increased bacterial speciation of environmental isolates from previous flights three fold compared to previous conventional methodology. The incorporation of molecular-based DNA fingerprinting using repetitive sequence-based polymerase chain reaction (rep-PCR) into the capabilities of the laboratory has provided a methodology to track microorganisms between crewmembers and their environment. Both 16S ribosomal DNA

  18. Ecology of Hypersaline Microorganisms

    Digital Repository Service at National Institute of Oceanography (India)

    Kerkar, S.

    of ancient seas. Deep Sea brines are relatively stable as a result of their higher density as reported in the Red Sea and Gulf of Mexico (MacDonald et al, 1990). Preliminary studies have suggested that microbial activity occurs in some Deep Sea hypersaline... partially characterized extreme halophile called ?Halobacterium sp GN101? (GN = Guerrero Negro, Mexico) (Ebert and Goebel, 1985). Hal R1 activity is typical with first activity detected during the transition from exponential to stationary phase...

  19. Microorganism immobilization

    Science.gov (United States)

    Compere, Alicia L.; Griffith, William L.

    1981-01-01

    Live metabolically active microorganisms are immobilized on a solid support by contacting particles of aggregate material with a water dispersible polyelectrolyte such as gelatin, crosslinking the polyelectrolyte by reacting it with a crosslinking agent such as glutaraldehyde to provide a crosslinked coating on the particles of aggregate material, contacting the coated particles with live microorganisms and incubating the microorganisms in contact with the crosslinked coating to provide a coating of metabolically active microorganisms. The immobilized microorganisms have continued growth and reproduction functions.

  20. Production of biosurfactant on crude date syrup under saline conditions by entrapped cells of Natrialba sp. strain E21, an extremely halophilic bacterium isolated from a solar saltern (Ain Salah, Algeria).

    Science.gov (United States)

    Kebbouche-Gana, Salima; Gana, Mohamed Lamine; Ferrioune, Imen; Khemili, Souad; Lenchi, Nesrine; Akmouci-Toumi, Sihem; Bouanane-Darenfed, Nabila Amel; Djelali, Nacer-Eddine

    2013-11-01

    A bacterial strain E21 was isolated from a sample of water collected in the salt lake located close to Ain Salah, Algeria. The analysis of 16S rRNA gene sequence had indicated that the strain had 93 % sequence similarity with the genus Natrialba sp. strain E21 (GenBank, FR750525.1) and was considered extremely halophilic. Production of biosurfactant by the strain E21 with free and entrapped cells was investigated using soluble starch in the saline conditions. Biosurfactant synthesis was followed by measuring the surface tension and emulsifying index 9 days under optimal conditions (40 °C, pH 7). Some diffusional limitations in alginate and agar beads affected the kinetics of biosurfactant production when compared to that obtained with free cells culture. The minimum values of surface tension were 27 and 30 mN m(-1) achieved after 9 days with free and immobilized cells, respectively, while the corresponding maximum E24 values were 65.3 and 62.3 %, respectively. The re-use of bacterial cells along with the limited cell losses provided by the immobilized system might lead to significant reduction of the biosurfactant production cost.

  1. Why Earth cryopegs are interesting to astrobiologists?

    Science.gov (United States)

    Rivkina, Elizaveta; Spirina, Elena; Demidov, Nikita; Shcherbakova, Viktoria; Yoshikawa, Kenji; Gilichinsky, David

    The lenses of perennially overcooled water brines (cryopegs) derived from ancient marine sedi-ments and sandwiched within permafrost 10 to 120,000 years ago after the placeArctic Ocean regressions. In these lenses freezing is prevented by freezing-point depression due to the dis-solved salt and they remain liquid at the in situ temperatures down to -11oC as a result of their high sodium-chloride concentration (3-5 mol/l). Cryopegs make up the only habitat on Earth that is characterized by permanently subzero temperatures, high salinity, and isolation from the influence of external factors during geological time. During last years the biodiversity of cryopeg's indigenous microbial community along the Arctic coast of placePlaceNamePolar PlaceTypeOcean (Kara and placeEast Siberian Sea, placePla-ceNameJamal PlaceTypePeninsula and placePlaceTypeCape PlaceNameBarrow) were studied and the new species representing the different genera have been isolated and described. There were found both aerobic and anaerobic microorganisms: Psychrobacters, Sulfate-reducers, Clostridia, etc. The isolated bacteria grew at subzero temperatures, and were also tolerant to salt concentra-tions up to metricconverterProductID3 M3 M NaCl. The microorganisms detected in cryopegs are halophilic and psychrophilic organisms at the same time. The microbial activity detected in cryopegs (14C-labeled glucose consumption) at temperatures as low as metricconverterProductID-15?C-15C-15° C documents the fact that subzero temper-atures themselves do not exclude biochemical reactions. In situ microbial activity and survival of microorganisms in a low-temperature high-salt aquatic environment on a geological time scale indicates the special type of microbial adaptation. From the astrobiological perspective, mineral-enriched brines provide the only opportunity for free water within the Martian subsurface permafrost, formed when Mars became dry and cold. These brines, just as terrestrial cryopegs, may contain

  2. Production of halophilic proteins using Haloferax volcanii H1895 in a stirred-tank bioreactor

    KAUST Repository

    Strillinger, Eva

    2015-10-01

    The success of biotechnological processes is based on the availability of efficient and highly specific biocatalysts, which can satisfy industrial demands. Extreme and remote environments like the deep brine pools of the Red Sea represent highly interesting habitats for the discovery of novel halophilic and thermophilic enzymes. Haloferax volcanii constitutes a suitable expression system for halophilic enzymes obtained from such brine pools. We developed a batch process for the cultivation of H. volcanii H1895 in controlled stirred-tank bioreactors utilising knockouts of components of the flagella assembly system. The standard medium Hv-YPC was supplemented to reach a higher cell density. Without protein expression, cell dry weight reaches 10 g L−1. Two halophilic alcohol dehydrogenases were expressed under the control of the tryptophanase promoter p.tna with 16.8 and 3.2 mg gCDW −1, respectively, at a maximum cell dry weight of 6.5 g L−1. Protein expression was induced by the addition of l-tryptophan. Investigation of various expression strategies leads to an optimised two-step induction protocol introducing 6 mM l-tryptophan at an OD650 of 0.4 followed by incubation for 16 h and a second induction step with 3 mM l-tryptophan followed by a final incubation time of 4 h. Compared with the uncontrolled shaker-flask cultivations used until date, dry cell mass concentrations were improved by a factor of more than 5 and cell-specific enzyme activities showed an up to 28-fold increased yield of the heterologous proteins.

  3. RNomics and Modomics in the halophilic archaea Haloferax volcanii: identification of RNA modification genes

    Directory of Open Access Journals (Sweden)

    Decatur Wayne A

    2008-10-01

    Full Text Available Abstract Background Naturally occurring RNAs contain numerous enzymatically altered nucleosides. Differences in RNA populations (RNomics and pattern of RNA modifications (Modomics depends on the organism analyzed and are two of the criteria that distinguish the three kingdoms of life. If the genomic sequences of the RNA molecules can be derived from whole genome sequence information, the modification profile cannot and requires or direct sequencing of the RNAs or predictive methods base on the presence or absence of the modifications genes. Results By employing a comparative genomics approach, we predicted almost all of the genes coding for the t+rRNA modification enzymes in the mesophilic moderate halophile Haloferax volcanii. These encode both guide RNAs and enzymes. Some are orthologous to previously identified genes in Archaea, Bacteria or in Saccharomyces cerevisiae, but several are original predictions. Conclusion The number of modifications in t+rRNAs in the halophilic archaeon is surprisingly low when compared with other Archaea or Bacteria, particularly the hyperthermophilic organisms. This may result from the specific lifestyle of halophiles that require high intracellular salt concentration for survival. This salt content could allow RNA to maintain its functional structural integrity with fewer modifications. We predict that the few modifications present must be particularly important for decoding, accuracy of translation or are modifications that cannot be functionally replaced by the electrostatic interactions provided by the surrounding salt-ions. This analysis also guides future experimental validation work aiming to complete the understanding of the function of RNA modifications in Archaeal translation.

  4. Production of halophilic proteins using Haloferax volcanii H1895 in a stirred-tank bioreactor.

    Science.gov (United States)

    Strillinger, Eva; Grötzinger, Stefan Wolfgang; Allers, Thorsten; Eppinger, Jörg; Weuster-Botz, Dirk

    2016-02-01

    The success of biotechnological processes is based on the availability of efficient and highly specific biocatalysts, which can satisfy industrial demands. Extreme and remote environments like the deep brine pools of the Red Sea represent highly interesting habitats for the discovery of novel halophilic and thermophilic enzymes. Haloferax volcanii constitutes a suitable expression system for halophilic enzymes obtained from such brine pools. We developed a batch process for the cultivation of H. volcanii H1895 in controlled stirred-tank bioreactors utilising knockouts of components of the flagella assembly system. The standard medium Hv-YPC was supplemented to reach a higher cell density. Without protein expression, cell dry weight reaches 10 g L(-1). Two halophilic alcohol dehydrogenases were expressed under the control of the tryptophanase promoter p.tna with 16.8 and 3.2 mg gCDW (-1), respectively, at a maximum cell dry weight of 6.5 g L(-1). Protein expression was induced by the addition of L-tryptophan. Investigation of various expression strategies leads to an optimised two-step induction protocol introducing 6 mM L-tryptophan at an OD650 of 0.4 followed by incubation for 16 h and a second induction step with 3 mM L-tryptophan followed by a final incubation time of 4 h. Compared with the uncontrolled shaker-flask cultivations used until date, dry cell mass concentrations were improved by a factor of more than 5 and cell-specific enzyme activities showed an up to 28-fold increased yield of the heterologous proteins.

  5. Production of halophilic proteins using Haloferax volcanii H1895 in a stirred-tank bioreactor

    KAUST Repository

    Strillinger, Eva; Grö tzinger, Stefan W.; Allers, Thorsten; Eppinger, Jö rg; Weuster-Botz, Dirk

    2015-01-01

    The success of biotechnological processes is based on the availability of efficient and highly specific biocatalysts, which can satisfy industrial demands. Extreme and remote environments like the deep brine pools of the Red Sea represent highly interesting habitats for the discovery of novel halophilic and thermophilic enzymes. Haloferax volcanii constitutes a suitable expression system for halophilic enzymes obtained from such brine pools. We developed a batch process for the cultivation of H. volcanii H1895 in controlled stirred-tank bioreactors utilising knockouts of components of the flagella assembly system. The standard medium Hv-YPC was supplemented to reach a higher cell density. Without protein expression, cell dry weight reaches 10 g L−1. Two halophilic alcohol dehydrogenases were expressed under the control of the tryptophanase promoter p.tna with 16.8 and 3.2 mg gCDW −1, respectively, at a maximum cell dry weight of 6.5 g L−1. Protein expression was induced by the addition of l-tryptophan. Investigation of various expression strategies leads to an optimised two-step induction protocol introducing 6 mM l-tryptophan at an OD650 of 0.4 followed by incubation for 16 h and a second induction step with 3 mM l-tryptophan followed by a final incubation time of 4 h. Compared with the uncontrolled shaker-flask cultivations used until date, dry cell mass concentrations were improved by a factor of more than 5 and cell-specific enzyme activities showed an up to 28-fold increased yield of the heterologous proteins.

  6. Antibiotic resistance of microbial contaminations isolated from husbandry animals and foodstuffs

    Directory of Open Access Journals (Sweden)

    Lukáš Hleba

    2014-05-01

    Full Text Available In this paper the antibiotic resistance of microbial contaminations isolated from husbandry animals and foodstuffs were investigated. Microorganisms isolated from animals and foodstuffs were contaminations of selective media as MacConkey agar for Enterobacteriaceae genera and MRS agar for lactobacilli strains. Microorganisms were isolated and puryfied by agar four ways streak plate method. Identification of isolated microorganisms was done by mass-spectrometry method in MALDI-TOF MS Biotyper. For investigation of antibiotic resistance disc diffusion method by EUCAST was used. In this study Gram-negative and Gram-positive bacteria were identified. The most resistant or multi-resistant bacteria as Pseudomonas aeruginosa, Acinetobacter lwoffi, Lysinibacillus sphaericus, Staphylococcus aureus and Staphylococcus epidermis were determined. Other identified microorganisms were resistant to one antibiotic or not at all.

  7. A patent landscape on application of microorganisms in construction industry.

    Science.gov (United States)

    Dapurkar, Dipti; Telang, Manasi

    2017-07-01

    Construction biotechnology includes research and development of construction materials and processes that make use of various microbes. The present technology landscape gives a perspective on how microbes have been used in construction industry as cement and concrete additives by analyzing patents filed in this technology arena. All patents related to the technology of interest published globally to date have been reviewed. The earliest patent filing in this technology domain was recorded in the year 1958 and the patenting activity reached its peak around mid to late 1990s. The early technology was mainly focused on microbial polysaccharides and other metabolic products as additives. Year 2002 onwards, biomineralization has taken precedence over the other technologies with consistent patent filings indicating a shift in innovation focus. Japan has been the global leader with highest number of patents filed on application of microbes in construction industry. Southeast University, China has topped the patent assignee list with maximum number of filings followed by Kajima Corp. and Shin-Etsu Chemical Co., Ltd. Most patent applications have claimed microbe based bio-products. Construction-related microbial technologies are mainly based on activity of different microorganisms such as urease-producing, acidogenic, halophilic, alkaliphilic, nitrate and iron-reducing bacteria. Sporosarcina pasteurii has been the most widely used microbe for biomineralization.

  8. Microorganisms isolated from cultures and infection focus and antibiotic treatments in febrile neutropenic children from Şanlıurfa, Turkey.

    Science.gov (United States)

    Özdemir, Z Canan; Koç, Ahmet; Ayçiçek, Ali

    2016-01-01

    Chemotherapy induced febrile neutropenia predisposes patients to life threatening infections. We aimed to determine the causative microorganisms, infection focus and antibiotic treatment success in febrile neutropenic children with leukemia. A total of 136 febrile neutropenic episodes in 48 leukemic children were reviewed retrospectively from records. Among 136 febrile neutropenic episodes, 68 (50%) episodes were microbiologically documented. Methicillin sensitive coagulase (-) Staphylococcus aureus were the most common isolates from hemoculture (20.5%). The most frequently documented infection focus was mucositis (31.9%). Ceftazidime plus amikacin was the most commonly used antimicrobial treatment for the empirical therapy (52.9%). The overall response rates were 70.5%, 86.9%, and 66.6% of first line, second line and third line therapies, respectively. The spectrum of isolates among febrile neutropenic children in our hematology clinic appears to be gram positive pathogens which are the most common agents. Therefore the, documentation of the flora in each unit could help to decide appropriate empirical therapy which is life saving.

  9. Analysis of bioremediation of pesticides by soil microorganisms

    Science.gov (United States)

    Ruml, Tomas; Klotz, Dietmar; Tykva, Richard

    1995-10-01

    The application of new pesticides requires careful monitoring of their distribution in the environment. The effect of the soil microflora on the stability of the [14C]- labelled juvenoid hormone analogue W-328 was estimated. The micro-organisms from two different soil samples were isolated and tested for their ability to decompose W-328. One bacterial strain, yeast and mold isolates, exhibited the degradation activity. The growth characteristics such as pH and temperature optima were determined. The degradation products were estimated using HPLC.

  10. Lignite microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Bulankina, M.A.; Lysak, L.V.; Zvyagintsev, D.G. [Moscow MV Lomonosov State University, Moscow (Russian Federation). Faculty of Soil Science

    2007-03-15

    The first demonstration that samples of lignite at a depth of 10 m are considerably enriched in bacteria is reported. According to direct microscopy, the abundance of bacteria was about 10{sup 7} cells/g. About 70% of cells had intact cell membranes and small size, which points to their anabiotic state. The fungal mycelium length was no more than 1 m. Lignite inoculation onto solid glucose-yeast-peptone medium allowed us to isolate bacteria of the genera Bacillus, Rhodococcus, Arthrobacter, Micrococcus, Spirillum, and Cytophaga. Representatives of the genera Penicillium and Trichoderma were identified on Czapek medium. Moistening of lignite powder increased the microbial respiration rate and microbial and fungal abundance but did not increase their generic diversity. This finding suggests that the studied microorganisms are autochthonous to lignite.

  11. Genome sequence of the moderately halophilic bacterium Salinicoccus carnicancri type strain Crm(T) (= DSM 23852(T)).

    Science.gov (United States)

    Hyun, Dong-Wook; Whon, Tae Woong; Cho, Yong-Joon; Chun, Jongsik; Kim, Min-Soo; Jung, Mi-Ja; Shin, Na-Ri; Kim, Joon-Yong; Kim, Pil Soo; Yun, Ji-Hyun; Lee, Jina; Oh, Sei Joon; Bae, Jin-Woo

    2013-01-01

    Salinicoccus carnicancri Jung et al. 2010 belongs to the genus Salinicoccus in the family Staphylococcaceae. Members of the Salinicoccus are moderately halophilic and originate from various salty environments. The halophilic features of the Salinicoccus suggest their possible uses in biotechnological applications, such as biodegradation and fermented food production. However, the genus Salinicoccus is poorly characterized at the genome level, despite its potential importance. This study presents the draft genome sequence of S. carnicancri strain Crm(T) and its annotation. The 2,673,309 base pair genome contained 2,700 protein-coding genes and 78 RNA genes with an average G+C content of 47.93 mol%. It was notable that the strain carried 72 predicted genes associated with osmoregulation, which suggests the presence of beneficial functions that facilitate growth in high-salt environments.

  12. Physiologically anaerobic microorganisms of the deep subsurface. Progress report, June 1, 1990--May 30, 1991

    Energy Technology Data Exchange (ETDEWEB)

    Stevens, S.E. Jr.; Chung, K.T.

    1991-06-01

    This study seeks to determine numbers, diversity, and morphology of anaerobic microorganisms in 15 samples of subsurface material from the Idaho National Engineering Laboratory, in 18 samples from the Hanford Reservation and in 1 rock sample from the Nevada Test Site; set up long term experiments on the chemical activities of anaerobic microorganisms based on these same samples; work to improve methods for the micro-scale determination of in situ anaerobic microbial activity;and to begin to isolate anaerobes from these samples into axenic culture with identification of the axenic isolates.

  13. Medical Significance of Microorganisms in Spacecraft Environment

    Science.gov (United States)

    Pierson, Duane L.; Ott, C. Mark

    2007-01-01

    Microorganisms can spoil food supplies, contaminate drinking water, release noxious volatile compounds, initiate allergic responses, contaminate the environment, and cause infectious diseases. International acceptability limits have been established for bacterial and fungal contaminants in air and on surfaces, and environmental monitoring is conducted to ensure compliance. Allowable levels of microorganism in water and food have also been established. Environmental monitoring of the space shuttle, the Mir, and the ISS have allowed for some general conclusions. Generally, the bacteria found in air and on interior surfaces are largely of human origin such as Staphylococcus spp., Micrococcus spp. Common environmental genera such as Bacillus spp. are the most commonly isolated bacteria from all spacecraft. Yeast species associated with humans such as Candida spp. are commonly found. Aspergillus spp., Penicillium spp., and Cladosporium spp. are the most commonly isolated filamentous fungi. Microbial levels in the environment differ significantly depending upon humidity levels, condensate accumulation, and availability of carbon sources. However, human "normal flora" of bacteria and fungi can result in serious, life-threatening diseases if human immunity is compromised. Disease incidence is expected to increase as mission duration increases.

  14. Using extremely halophilic bacteria to understand the role of surface charge and surface hydration in protein evolution, folding, and function

    Science.gov (United States)

    Hoff, Wouter; Deole, Ratnakar; Osu Collaboration

    2013-03-01

    Halophilic Archaea accumulate molar concentrations of KCl in their cytoplasm as an osmoprotectant, and have evolved highly acidic proteomes that only function at high salinity. We examine osmoprotection in the photosynthetic Proteobacteria Halorhodospira halophila. We find that H. halophila has an acidic proteome and accumulates molar concentrations of KCl when grown in high salt media. Upon growth of H. halophila in low salt media, its cytoplasmic K + content matches that of Escherichia coli, revealing an acidic proteome that can function in the absence of high cytoplasmic salt concentrations. These findings necessitate a reassessment of two central aspects of theories for understanding extreme halophiles. We conclude that proteome acidity is not driven by stabilizing interactions between K + ions and acidic side chains, but by the need for maintaining sufficient solvation and hydration of the protein surface at high salinity through strongly hydrated carboxylates. We propose that obligate protein halophilicity is a non-adaptive property resulting from genetic drift in which constructive neutral evolution progressively incorporates weakly stabilizing K + binding sites on an increasingly acidic protein surface.

  15. Adaptations to High Salt in a Halophilic Protist: Differential Expression and Gene Acquisitions through Duplications and Gene Transfers

    Science.gov (United States)

    Harding, Tommy; Roger, Andrew J.; Simpson, Alastair G. B.

    2017-01-01

    The capacity of halophiles to thrive in extreme hypersaline habitats derives partly from the tight regulation of ion homeostasis, the salt-dependent adjustment of plasma membrane fluidity, and the increased capability to manage oxidative stress. Halophilic bacteria, and archaea have been intensively studied, and substantial research has been conducted on halophilic fungi, and the green alga Dunaliella. By contrast, there have been very few investigations of halophiles that are phagotrophic protists, i.e., protozoa. To gather fundamental knowledge about salt adaptation in these organisms, we studied the transcriptome-level response of Halocafeteria seosinensis (Stramenopiles) grown under contrasting salinities. We provided further evolutionary context to our analysis by identifying genes that underwent recent duplications. Genes that were highly responsive to salinity variations were involved in stress response (e.g., chaperones), ion homeostasis (e.g., Na+/H+ transporter), metabolism and transport of lipids (e.g., sterol biosynthetic genes), carbohydrate metabolism (e.g., glycosidases), and signal transduction pathways (e.g., transcription factors). A significantly high proportion (43%) of duplicated genes were also differentially expressed, accentuating the importance of gene expansion in adaptation by H. seosinensis to high salt environments. Furthermore, we found two genes that were lateral acquisitions from bacteria, and were also highly up-regulated and highly expressed at high salt, suggesting that this evolutionary mechanism could also have facilitated adaptation to high salt. We propose that a transition toward high-salt adaptation in the ancestors of H. seosinensis required the acquisition of new genes via duplication, and some lateral gene transfers (LGTs), as well as the alteration of transcriptional programs, leading to increased stress resistance, proper establishment of ion gradients, and modification of cell structure properties like membrane

  16. Adaptations to High Salt in a Halophilic Protist: Differential Expression and Gene Acquisitions through Duplications and Gene Transfers

    Directory of Open Access Journals (Sweden)

    Tommy Harding

    2017-05-01

    Full Text Available The capacity of halophiles to thrive in extreme hypersaline habitats derives partly from the tight regulation of ion homeostasis, the salt-dependent adjustment of plasma membrane fluidity, and the increased capability to manage oxidative stress. Halophilic bacteria, and archaea have been intensively studied, and substantial research has been conducted on halophilic fungi, and the green alga Dunaliella. By contrast, there have been very few investigations of halophiles that are phagotrophic protists, i.e., protozoa. To gather fundamental knowledge about salt adaptation in these organisms, we studied the transcriptome-level response of Halocafeteria seosinensis (Stramenopiles grown under contrasting salinities. We provided further evolutionary context to our analysis by identifying genes that underwent recent duplications. Genes that were highly responsive to salinity variations were involved in stress response (e.g., chaperones, ion homeostasis (e.g., Na+/H+ transporter, metabolism and transport of lipids (e.g., sterol biosynthetic genes, carbohydrate metabolism (e.g., glycosidases, and signal transduction pathways (e.g., transcription factors. A significantly high proportion (43% of duplicated genes were also differentially expressed, accentuating the importance of gene expansion in adaptation by H. seosinensis to high salt environments. Furthermore, we found two genes that were lateral acquisitions from bacteria, and were also highly up-regulated and highly expressed at high salt, suggesting that this evolutionary mechanism could also have facilitated adaptation to high salt. We propose that a transition toward high-salt adaptation in the ancestors of H. seosinensis required the acquisition of new genes via duplication, and some lateral gene transfers (LGTs, as well as the alteration of transcriptional programs, leading to increased stress resistance, proper establishment of ion gradients, and modification of cell structure properties like

  17. Biodegradation of benzene by halophilic and halotolerant bacteria under aerobic conditions.

    Science.gov (United States)

    Nicholson, Carla A; Fathepure, Babu Z

    2004-02-01

    A highly enriched halophilic culture was established with benzene as the sole carbon source by using a brine soil obtained from an oil production facility in Oklahoma. The enrichment completely degraded benzene, toluene, ethylbenzene, and xylenes within 1 to 2 weeks. Also, [14C]benzene was converted to 14CO2, suggesting the culture's ability to mineralize benzene. Community structure analysis revealed that Marinobacter spp. were the dominant members of the enrichment.

  18. Chloride and organic osmolytes: a hybrid strategy to cope with elevated salinities by the moderately halophilic, chloride-dependent bacterium Halobacillus halophilus.

    Science.gov (United States)

    Saum, Stephan H; Pfeiffer, Friedhelm; Palm, Peter; Rampp, Markus; Schuster, Stephan C; Müller, Volker; Oesterhelt, Dieter

    2013-05-01

    Salt acclimation in moderately halophilic bacteria is the result of action of a grand interplay orchestrated by signals perceived from the environment. To elucidate the cellular players involved in sensing and responding to changing salinities we have determined the genome sequence of Halobacillus halophilus, a Gram-positive moderate halophilic bacterium that has a strict requirement for the anion chloride. Halobacillus halophilus synthesizes a multitude of different compatible solutes and switches its osmolyte strategy with the external salinity and growth phase. Based on the emerging genome sequence, the compatible solutes glutamate, glutamine, proline and ectoine have already been experimentally studied. The biosynthetic routes for acetyl ornithine and acetyl lysine are also delineated from the genome sequence. Halobacillus halophilus is nutritionally very versatile and most compatible solutes cannot only be produced but also used as carbon and energy sources. The genome sequence unravelled isogenes for many pathways indicating a fine regulation of metabolism. Halobacillus halophilus is unique in integrating the concept of compatible solutes with the second fundamental principle to cope with salt stress, the accumulation of molar concentrations of salt (Cl(-)) in the cytoplasm. Extremely halophilic bacteria/archaea, which exclusively rely on the salt-in strategy, have a high percentage of acidic proteins compared with non-halophiles with a low percentage. Halobacillus halophilus has an intermediate position which is consistent with its ability to integrate both principles. © 2012 Society for Applied Microbiology and Blackwell Publishing Ltd.

  19. Differences in lateral gene transfer in hypersaline versus thermal environments

    Directory of Open Access Journals (Sweden)

    House Christopher H

    2011-07-01

    Full Text Available Abstract Background The role of lateral gene transfer (LGT in the evolution of microorganisms is only beginning to be understood. While most LGT events occur between closely related individuals, inter-phylum and inter-domain LGT events are not uncommon. These distant transfer events offer potentially greater fitness advantages and it is for this reason that these "long distance" LGT events may have significantly impacted the evolution of microbes. One mechanism driving distant LGT events is microbial transformation. Theoretically, transformative events can occur between any two species provided that the DNA of one enters the habitat of the other. Two categories of microorganisms that are well-known for LGT are the thermophiles and halophiles. Results We identified potential inter-class LGT events into both a thermophilic class of Archaea (Thermoprotei and a halophilic class of Archaea (Halobacteria. We then categorized these LGT genes as originating in thermophiles and halophiles respectively. While more than 68% of transfer events into Thermoprotei taxa originated in other thermophiles, less than 11% of transfer events into Halobacteria taxa originated in other halophiles. Conclusions Our results suggest that there is a fundamental difference between LGT in thermophiles and halophiles. We theorize that the difference lies in the different natures of the environments. While DNA degrades rapidly in thermal environments due to temperature-driven denaturization, hypersaline environments are adept at preserving DNA. Furthermore, most hypersaline environments, as topographical minima, are natural collectors of cellular debris. Thus halophiles would in theory be exposed to a greater diversity and quantity of extracellular DNA than thermophiles.

  20. Differences in lateral gene transfer in hypersaline versus thermal environments.

    Science.gov (United States)

    Rhodes, Matthew E; Spear, John R; Oren, Aharon; House, Christopher H

    2011-07-08

    The role of lateral gene transfer (LGT) in the evolution of microorganisms is only beginning to be understood. While most LGT events occur between closely related individuals, inter-phylum and inter-domain LGT events are not uncommon. These distant transfer events offer potentially greater fitness advantages and it is for this reason that these "long distance" LGT events may have significantly impacted the evolution of microbes. One mechanism driving distant LGT events is microbial transformation. Theoretically, transformative events can occur between any two species provided that the DNA of one enters the habitat of the other. Two categories of microorganisms that are well-known for LGT are the thermophiles and halophiles. We identified potential inter-class LGT events into both a thermophilic class of Archaea (Thermoprotei) and a halophilic class of Archaea (Halobacteria). We then categorized these LGT genes as originating in thermophiles and halophiles respectively. While more than 68% of transfer events into Thermoprotei taxa originated in other thermophiles, less than 11% of transfer events into Halobacteria taxa originated in other halophiles. Our results suggest that there is a fundamental difference between LGT in thermophiles and halophiles. We theorize that the difference lies in the different natures of the environments. While DNA degrades rapidly in thermal environments due to temperature-driven denaturization, hypersaline environments are adept at preserving DNA. Furthermore, most hypersaline environments, as topographical minima, are natural collectors of cellular debris. Thus halophiles would in theory be exposed to a greater diversity and quantity of extracellular DNA than thermophiles.

  1. Osmoregulation in the Halophilic Bacterium Halomonas elongata: A Case Study for Integrative Systems Biology.

    Science.gov (United States)

    Kindzierski, Viktoria; Raschke, Silvia; Knabe, Nicole; Siedler, Frank; Scheffer, Beatrix; Pflüger-Grau, Katharina; Pfeiffer, Friedhelm; Oesterhelt, Dieter; Marin-Sanguino, Alberto; Kunte, Hans-Jörg

    2017-01-01

    Halophilic bacteria use a variety of osmoregulatory methods, such as the accumulation of one or more compatible solutes. The wide diversity of compounds that can act as compatible solute complicates the task of understanding the different strategies that halophilic bacteria use to cope with salt. This is specially challenging when attempting to go beyond the pathway that produces a certain compatible solute towards an understanding of how the metabolic network as a whole addresses the problem. Metabolic reconstruction based on genomic data together with Flux Balance Analysis (FBA) is a promising tool to gain insight into this problem. However, as more of these reconstructions become available, it becomes clear that processes predicted by genome annotation may not reflect the processes that are active in vivo. As a case in point, E. coli is unable to grow aerobically on citrate in spite of having all the necessary genes to do it. It has also been shown that the realization of this genetic potential into an actual capability to metabolize citrate is an extremely unlikely event under normal evolutionary conditions. Moreover, many marine bacteria seem to have the same pathways to metabolize glucose but each species uses a different one. In this work, a metabolic network inferred from genomic annotation of the halophilic bacterium Halomonas elongata and proteomic profiling experiments are used as a starting point to motivate targeted experiments in order to find out some of the defining features of the osmoregulatory strategies of this bacterium. This new information is then used to refine the network in order to describe the actual capabilities of H. elongata, rather than its genetic potential.

  2. Identification of selected microorganisms from activated sludge capable of benzothiazole and benzotriazole transformation.

    Science.gov (United States)

    Kowalska, Katarzyna; Felis, Ewa

    2015-01-01

    Benzothiazole (BT) and benzotriazole (BTA) are present in the environment - especially in urban and industrial areas, usually as anthropogenic micropollutants. BT and BTA have been found in the municipal and industrial wastewater, rivers, soil, groundwater, sediments and sludge. The origins of those substances' presence in the environment are various industry branches (food, chemical, metallurgical, electrical), households and surface runoff from industrial areas. Increasingly strict regulations on water quality and the fact that the discussed compounds are poorly biodegradable, make them a serious problem in the environment. Considering this, it is important to look for environmentally friendly and socially acceptable ways to remove BT and BTA. The aim of this study was to identify microorganisms capable of BT and BTA transformation or/and degradation in aquatic environment. Selected microorganisms were isolated from activated sludge. The identification of microorganisms capable of BT and BTA removal was possible using molecular biology techniques (PCR, DNA sequencing). Among isolated microorganisms of activated sludge are bacteria potentially capable of BT and BTA biotransformation and/or removal. The most common bacteria capable of BT and BTA transformation were Rhodococcus sp., Enterobacter sp., Arthrobacter sp. They can grow in a medium with BT and BTA as the only carbon source. Microorganisms previously adapted to the presence of the studied substances at a concentration of 10 mg/l, showed a greater rate of growth of colonies on media than microorganisms unconditioned to the presence of such compounds. Results of the biodegradation test suggest that BT was degraded to a greater extent than BTA, 98-100% and 11-19%, respectively.

  3. An Extremely Halophilic Proteobacterium Combines a Highly Acidic Proteome with a Low Cytoplasmic Potassium Content*

    Science.gov (United States)

    Deole, Ratnakar; Challacombe, Jean; Raiford, Douglas W.; Hoff, Wouter D.

    2013-01-01

    Halophilic archaea accumulate molar concentrations of KCl in their cytoplasm as an osmoprotectant and have evolved highly acidic proteomes that function only at high salinity. We examined osmoprotection in the photosynthetic Proteobacteria Halorhodospira halophila and Halorhodospira halochloris. Genome sequencing and isoelectric focusing gel electrophoresis showed that the proteome of H. halophila is acidic. In line with this finding, H. halophila accumulated molar concentrations of KCl when grown in high salt medium as detected by x-ray microanalysis and plasma emission spectrometry. This result extends the taxonomic range of organisms using KCl as a main osmoprotectant to the Proteobacteria. The closely related organism H. halochloris does not exhibit an acidic proteome, matching its inability to accumulate K+. This observation indicates recent evolutionary changes in the osmoprotection strategy of these organisms. Upon growth of H. halophila in low salt medium, its cytoplasmic K+ content matches that of Escherichia coli, revealing an acidic proteome that can function in the absence of high cytoplasmic salt concentrations. These findings necessitate a reassessment of two central aspects of theories for understanding extreme halophiles. First, we conclude that proteome acidity is not driven by stabilizing interactions between K+ ions and acidic side chains but by the need for maintaining sufficient solvation and hydration of the protein surface at high salinity through strongly hydrated carboxylates. Second, we propose that obligate protein halophilicity is a non-adaptive property resulting from genetic drift in which constructive neutral evolution progressively incorporates weakly stabilizing K+-binding sites on an increasingly acidic protein surface. PMID:23144460

  4. Complete Genome Sequence of the Anaerobic Halophilic Alkalithermophile Natranaerobius thermophilus JW/NM-WN-LFT

    Energy Technology Data Exchange (ETDEWEB)

    Mesbah, Noha [University of Georgia, Athens, GA; Dalin, Eileen [U.S. Department of Energy, Joint Genome Institute; Goodwin, Lynne A. [Los Alamos National Laboratory (LANL); Nolan, Matt [U.S. Department of Energy, Joint Genome Institute; Pitluck, Sam [U.S. Department of Energy, Joint Genome Institute; Chertkov, Olga [Los Alamos National Laboratory (LANL); Han, James [U.S. Department of Energy, Joint Genome Institute; Larimer, Frank W [ORNL; Land, Miriam L [ORNL; Hauser, Loren John [ORNL; Kyrpides, Nikos C [U.S. Department of Energy, Joint Genome Institute; Wiegel, Juergen [University of Georgia, Athens, GA

    2011-01-01

    The genome of the anaerobic halophilic alkalithermophile Natranaerobius thermophiles consists of one chromosome and two plasmids.The present study is the first to report the completely sequenced genome of polyextremophile and the harboring genes harboring genes associated with roles in regulation of intracellular osmotic pressure, pH homeostasis, and thermophilic stability.

  5. Screening concepts for the isolation of biosurfactant producing microorganisms.

    Science.gov (United States)

    Walter, Vanessa; Syldatk, Christoph; Hausmann, Rudolf

    2010-01-01

    This chapter gives an overview of current methods for the isolation of biosurfactant producing microbes. The common screening methods for biosurfactants are presented. Sampling and isolation of bacteria are the basis for screening of biosurfactant producing microbes. Hydrocarbon-contaminated sites are the most promising for the isolation of biosurfactant producing microbes, but many strains have also been isolated from undisturbed sites. In subsequent steps the isolates have to be characterized in order to identify the strains which are interesting for a further investigation. Several techniques have been developed for identifying biosurfactant producing strains. Most of them are directly based on the surface or interfacial activity of the culture supernatant. Apart from that, some screening methods explore the hydrophobicity of the cell surface. This trait also gives an indication on biosurfactant production. In recent years automation and miniaturization have led to the development of high throughput methods for screening. High throughput screening (HTS) for analyzing large amounts of potential candidates or whole culture collections is reflected in the end. However, no new principals have been introduced by HTS methods.

  6. Ventilator-associated pneumonia at a tertiary-care center in a developing country: incidence, microbiology, and susceptibility patterns of isolated microorganisms.

    Science.gov (United States)

    Kanafani, Zeina A; Kara, Layla; Hayek, Shady; Kanj, Souha S

    2003-11-01

    Ventilator-associated pneumonia (VAP) complicates the course of up to 24% of intubated patients. Data from the Middle East are scarce. The objective of this study was to evaluate the incidence, microbiology, and antimicrobial susceptibility patterns of isolated microorganisms in VAP in a developing country. Prospective observational cohort study. The American University of Beirut Medical Center, a tertiary-care center that serves as a major referral center for Lebanon and neighboring countries. All patients admitted to the intensive care and respiratory care units from March to September 2001, and who had been receiving mechanical ventilation for at least 48 hours, were included in the study. Results of samples submitted for culture were recorded and antimicrobial susceptibility testing of isolated pathogens was performed. Seventy patients were entered into the study. The incidence of VAP was 47%. Gram-negative bacilli accounted for 83% of all isolates. The most commonly identified organism was Acinetobacter anitratus, followed by Pseudomonas aeruginosa. Fifty percent of all gram-negative bacterial isolates were classified as antibiotic resistant. Compared with patients without VAP, patients with VAP remained intubated for a longer period and stayed in the intensive care unit longer. VAP was not associated with an increased mortality rate. Compared with other studies, the results from this referral center in Lebanon indicate a higher incidence of VAP and a high prevalence of resistant organisms. These data are relevant because they direct the choice of empiric antibiotic therapy for VAP.

  7. The first collection of spacecraft-associated microorganisms: a public source for extremotolerant microorganisms from spacecraft assembly clean rooms.

    Science.gov (United States)

    Moissl-Eichinger, Christine; Rettberg, Petra; Pukall, Rüdiger

    2012-11-01

    For several reasons, spacecraft are constructed in so-called clean rooms. Particles could affect the function of spacecraft instruments, and for missions under planetary protection limitations, the biological contamination has to be restricted as much as possible. The proper maintenance of clean rooms includes, for instance, constant control of humidity and temperature, air filtering, and cleaning (disinfection) of the surfaces. The combination of these conditions creates an artificial, extreme biotope for microbial survival specialists: spore formers, autotrophs, multi-resistant, facultative, or even strictly anaerobic microorganisms have been detected in clean room habitats. Based on a diversity study of European and South-American spacecraft assembly clean rooms, the European Space Agency (ESA) has initialized and funded the creation of a public library of microbial isolates. Isolates from three different European clean rooms, as well as from the final assembly and launch facility in Kourou (French Guiana), have been phylogenetically analyzed and were lyophilized for long-term storage at the German Culture Collection facilities in Brunswick, Germany (Leibniz-Institut DSMZ-Deutsche Sammlung von Mikroorganismen und Zellkulturen). The isolates were obtained by either following the standard protocol for the determination of bioburden on, and around, spacecraft or the use of alternative cultivation strategies. Currently, the database contains 298 bacterial strains. Fifty-nine strains are Gram-negative microorganisms, belonging to the α-, β- and γ-Proteobacteria. Representatives of the Gram-positive phyla Actinobacteria, Bacteroidetes/Chlorobi, and Firmicutes were subjected to the collection. Ninety-four isolates (21 different species) of the genus Bacillus were included in the ESA collection. This public collection of extremotolerant microbes, which are adapted to a complicated artificial biotope, provides a wonderful source for industry and research focused on

  8. Characterization of detergent compatible protease from halophilic Virgibacillus sp. CD6.

    Science.gov (United States)

    Lam, Ming Quan; Nik Mut, Nik Nurhidayu; Thevarajoo, Suganthi; Chen, Sye Jinn; Selvaratnam, Chitra; Hussin, Huszalina; Jamaluddin, Haryati; Chong, Chun Shiong

    2018-02-01

    A halophilic bacterium, Virgibacillus sp. strain CD6, was isolated from salted fish and its extracellular protease was characterized. Protease production was found to be highest when yeast extract was used as nitrogen source for growth. The protease exhibited stability at wide range of salt concentration (0-12.5%, w/v), temperatures (20-60 °C), and pH (4-10) with maximum activity at 10.0% (w/v) NaCl, 60 °C, pH 7 and 10, indicating its polyextremophilicity. The protease activity was enhanced in the presence of Mg 2+ , Mn 2+ , Cd 2+ , and Al 3+ (107-122% relative activity), and with retention of activity > 80% for all of other metal ions examined (K + , Ca 2+ , Cu 2+ , Co 2+ , Ni 2+ , Zn 2+ , and Fe 3+ ). Both PMSF and EDTA inhibited protease activity, denoting serine protease and metalloprotease properties, respectively. High stability (> 70%) was demonstrated in the presence of organic solvents and detergent constituents, and the extracellular protease from strain CD6 was also found to be compatible in commercial detergents. Proteinaceous stain removal efficacy revealed that crude protease of strain CD6 could significantly enhance the performance of commercial detergent. The protease from Virgibacillus sp. strain CD6 could serve as a promising alternative for various applications, especially in detergent industry.

  9. Marinospirillum gen. nov., with descriptions of Marinospirillum megaterium sp. nov., isolated from kusaya gravy, and transfer of Oceanospirillum minutulum to Marinospirillum minutulum comb. nov.

    Science.gov (United States)

    Satomi, M; Kimura, B; Hayashi, M; Shouzen, Y; Okuzumi, M; Fujii, T

    1998-10-01

    Two strains of helical, halophilic, Gram-negative, heterotrophic bacteria were isolated from kusaya gravy which is a traditional Japanese fermented brine. These strains were motile by means of a single polar or bipolar tuft flagellum. They had a large cell size, were helical, formed coccoid bodies, were microaerophilic and had quinone type Q-8. The DNA G + C content of the strains was 44-45 mol %. A detailed investigation of the phenotypic, chemotaxonomic and phylogenetic characteristics of the strains revealed that they represent a new species of halophilic helical bacteria. The sequence of the 16S rRNA gene of strain H7T, designated the type strain of the new isolates, and all of the Oceanospirillum species except for Oceanospirillum linum were determined. Phylogenetic analysis indicated that these strains were closely related to Oceanospirillum minutulum, with enough distance to separate the O. minutulum/new isolate H7T cluster from Oceanospirillum sensu stricto on the genus level. It is proposed that a new genus, Marinospirillum, be created; this genus should include Marinospirillum minutulum ATCC 19193T (formerly Oceanospirillum minutulum) as the type species, as well as Marinospirillum megaterium JCM 10129T (= H7T).

  10. Study of radioresistance of microorganisms

    International Nuclear Information System (INIS)

    Olbrichova, D.

    1983-01-01

    Strain radiosensitivity was evaluated on the basis of the determination of inactivation curve parameters and the determination of the D 10 value. The course of curves was investigated for two 60 Co sources, RCHM-gamma-20 (USSR) with an activity of 2.54x10 14 Bq and AECL (type J-6000, Canada) with an activity of 4.92x10 16 Bq. The curve parameters were determined for microorganisms in buffer medium and for cultures in dehydrated condition. Coccus germs were irradiated with doses of 1, 2, 3, 4, 5 and 6 kGy and aerobic sporulates with doses of 3, 6, 9, 12 and 15 kGy. For comparing the resistance of isolated strains the t-test was used. The most resistant of the isolated strains were Bacillus cereus, Bacillus subtilis, Bacillus pumilus and Bacillus megatherium. (E.S.)

  11. Mini-review: Inhibition of biofouling by marine microorganisms.

    Science.gov (United States)

    Dobretsov, Sergey; Abed, Raeid M M; Teplitski, Max

    2013-01-01

    Any natural or artificial substratum exposed to seawater is quickly fouled by marine microorganisms and later by macrofouling species. Microfouling organisms on the surface of a substratum form heterogenic biofilms, which are composed of multiple species of heterotrophic bacteria, cyanobacteria, diatoms, protozoa and fungi. Biofilms on artificial structures create serious problems for industries worldwide, with effects including an increase in drag force and metal corrosion as well as a reduction in heat transfer efficiency. Additionally, microorganisms produce chemical compounds that may induce or inhibit settlement and growth of other fouling organisms. Since the last review by the first author on inhibition of biofouling by marine microbes in 2006, significant progress has been made in the field. Several antimicrobial, antialgal and antilarval compounds have been isolated from heterotrophic marine bacteria, cyanobacteria and fungi. Some of these compounds have multiple bioactivities. Microorganisms are able to disrupt biofilms by inhibition of bacterial signalling and production of enzymes that degrade bacterial signals and polymers. Epibiotic microorganisms associated with marine algae and invertebrates have a high antifouling (AF) potential, which can be used to solve biofouling problems in industry. However, more information about the production of AF compounds by marine microorganisms in situ and their mechanisms of action needs to be obtained. This review focuses on the AF activity of marine heterotrophic bacteria, cyanobacteria and fungi and covers publications from 2006 up to the end of 2012.

  12. Isolation and Cultivation of Anaerobes

    DEFF Research Database (Denmark)

    Aragao Börner, Rosa

    2016-01-01

    Anaerobic microorganisms play important roles in different biotechnological processes. Their complex metabolism and special cultivation requirements have led to less isolated representatives in comparison to their aerobic counterparts.In view of that, the isolation and cultivation of anaerobic...

  13. Bioremediation of trinitrotolulene by a ruminal microorganism

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Taejin; Williamson, K.J.; Craig, A.M. [Oregon State Univ., Corvallis, OR (United States)

    1995-10-01

    2,4,6-trinitrotoluene (TNT) has been widely used for the production of explosives because of its low boiling point, high stability, low impact sensitivity, and safe manufacture. More than 1,100 military facilities, each potentially contaminated with munitions waste, are expected to require treatment of more than one million cubic yards of contaminated soils. The cost associated with remediation of these sites has been estimated to be in excess of $1.5 billion. Recently, researchers have studied ruminal microorganisms in relation to their ability to degrade xenobiotic compounds. Many of these organisms are strict anaerobes with optimal redox potentials as low as -420 mV. Ruminal organisms have been shown capable of destroying some pesticides, such as parathion, p-nitrophenol, and biphenyl-type compounds; thiono isomers, and nitrogen-containing heterocyclic plant toxins such as the pyrrolizidine alkaloids. Many of these compounds have structures similar to TNT. A TNT-degrading ruminal microorganism has been isolated from goat rumen fluid with successive enrichments on triaminotoluene (TAT) and TNT. The isolate, designated G.8, utilizes nitrate and lactate as the primary energy source. G.8 was able to tolerate and metabolite levels of TNT up to the saturation point of 125 mg/l.

  14. Metabolic flux analysis of the halophilic archaeon Haladaptatus paucihalophilus

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Guangxiu; Zhang, Manxiao [Key Laboratory of Desert and Desertification, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, 730000 (China); Key Laboratory of Extreme Environmental Microbial Resources and Engineering, Gansu Province, Lanzhou, 730000 (China); Mo, Tianlu [Department of Chemistry, Fudan University, Shanghai, 200433 (China); He, Lian [Key Laboratory of Combinatory Biosynthesis and Drug Discovery (Ministry of Education), School of Pharmaceutical Sciences, Wuhan University, Wuhan, 430071 (China); Zhang, Wei [Key Laboratory of Desert and Desertification, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, 730000 (China); Key Laboratory of Extreme Environmental Microbial Resources and Engineering, Gansu Province, Lanzhou, 730000 (China); Yu, Yi, E-mail: yu_yi@whu.edu.cn [Key Laboratory of Combinatory Biosynthesis and Drug Discovery (Ministry of Education), School of Pharmaceutical Sciences, Wuhan University, Wuhan, 430071 (China); Zhang, Qi, E-mail: qizhang@sioc.ac.cn [Department of Chemistry, Fudan University, Shanghai, 200433 (China); Ding, Wei, E-mail: dingw@lzu.edu.cn [Key Laboratory of Desert and Desertification, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou, 730000 (China); Key Laboratory of Extreme Environmental Microbial Resources and Engineering, Gansu Province, Lanzhou, 730000 (China); Department of Chemistry, Fudan University, Shanghai, 200433 (China)

    2015-11-27

    This work reports the {sup 13}C-assisted metabolic flux analysis of Haladaptatus paucihalophilus, a halophilic archaeon possessing an intriguing osmoadaption mechanism. We showed that the carbon flow is through the oxidative tricarboxylic acid (TCA) cycle whereas the reductive TCA cycle is not operative in H. paucihalophilus. In addition, both threonine and the citramalate pathways contribute to isoleucine biosynthesis, whereas lysine is synthesized through the diaminopimelate pathway and not through the α-aminoadipate pathway. Unexpected, the labeling patterns of glycine from the cells grown on [1-{sup 13}C]pyruvate and [2-{sup 13}C]pyruvate suggest that, unlike all the organisms investigated so far, in which glycine is produced exclusively from the serine hydroxymethyltransferase (SHMT) pathway, glycine biosynthesis in H. paucihalophilus involves different pathways including SHMT, threonine aldolase (TA) and the reverse reaction of glycine cleavage system (GCS), demonstrating for the first time that other pathways instead of SHMT can also make a significant contribution to the cellular glycine pool. Transcriptional analysis confirmed that both TA and GCS genes were transcribed in H. paucihalophilus, and the transcriptional level is independent of salt concentrations in the culture media. This study expands our understanding of amino acid biosynthesis and provides valuable insights into the metabolism of halophilic archaea. - Highlights: • Serine hydroxymethyltransferase, threonine aldolase, and glycine cleavage system all contribute to the glycine pool of H. paucihalophilus. • Threonine and the citramalate pathways contribute equally to the isoleucine biosynthesis in H. paucihalophilus. • Lysine in H. paucihalophilus is synthesized through the diaminopimelate pathway and not through the α-aminoadipate pathway. • Glycine biosynthesis is likely unrelated to the cell osmoadaption mechanism.

  15. Metabolic flux analysis of the halophilic archaeon Haladaptatus paucihalophilus

    International Nuclear Information System (INIS)

    Liu, Guangxiu; Zhang, Manxiao; Mo, Tianlu; He, Lian; Zhang, Wei; Yu, Yi; Zhang, Qi; Ding, Wei

    2015-01-01

    This work reports the "1"3C-assisted metabolic flux analysis of Haladaptatus paucihalophilus, a halophilic archaeon possessing an intriguing osmoadaption mechanism. We showed that the carbon flow is through the oxidative tricarboxylic acid (TCA) cycle whereas the reductive TCA cycle is not operative in H. paucihalophilus. In addition, both threonine and the citramalate pathways contribute to isoleucine biosynthesis, whereas lysine is synthesized through the diaminopimelate pathway and not through the α-aminoadipate pathway. Unexpected, the labeling patterns of glycine from the cells grown on [1-"1"3C]pyruvate and [2-"1"3C]pyruvate suggest that, unlike all the organisms investigated so far, in which glycine is produced exclusively from the serine hydroxymethyltransferase (SHMT) pathway, glycine biosynthesis in H. paucihalophilus involves different pathways including SHMT, threonine aldolase (TA) and the reverse reaction of glycine cleavage system (GCS), demonstrating for the first time that other pathways instead of SHMT can also make a significant contribution to the cellular glycine pool. Transcriptional analysis confirmed that both TA and GCS genes were transcribed in H. paucihalophilus, and the transcriptional level is independent of salt concentrations in the culture media. This study expands our understanding of amino acid biosynthesis and provides valuable insights into the metabolism of halophilic archaea. - Highlights: • Serine hydroxymethyltransferase, threonine aldolase, and glycine cleavage system all contribute to the glycine pool of H. paucihalophilus. • Threonine and the citramalate pathways contribute equally to the isoleucine biosynthesis in H. paucihalophilus. • Lysine in H. paucihalophilus is synthesized through the diaminopimelate pathway and not through the α-aminoadipate pathway. • Glycine biosynthesis is likely unrelated to the cell osmoadaption mechanism.

  16. Identification of subsurface microorganisms at Yucca Mountain

    International Nuclear Information System (INIS)

    Stetzenbach, L.D.

    1994-01-01

    Bacteria isolated from ground water samples taken from 31 springs during 1993 were collected and processed according to procedures described in earlier reports. These procedures required aseptic collection of surface water samples in sterile screw-capped containers, transportation to the HRC microbiology laboratory, and culture by spread plating onto R2A medium. The isolates were further processed for identification using a gas chromatographic analysis of fatty acid methyl esters (FAME) extracted from cell membranes. This work generated a presumptive identification of 113 bacterial species distributed among 45 genera using a database obtained from Microbial ID, Inc., Newark, Delaware (MIDI). A preliminary examination of the FAME data was accomplished using cluster analysis and principal component analysis software obtained from MIDI. Typically, bacterial strains that cluster at less than 10 Euclidian distance units have fatty acid patterns consistent among members of the same species. Thus an organism obtained from one source can be recognized if it is isolated again from the same or any other source. This makes it possible to track the distribution of organisms and monitor environmental conditions or fluid transport mechanisms. Microorganisms are seldom found as monocultures in natural environments. They are more likely to be closely associated with other genera with complementary metabolic requirements. An understanding of the indigenous microorganism population is useful in understanding subtle changes in the environment. However, classification of environmental organisms using traditional methods is not ideal because differentiation of species with small variations or genera with very similar taxonomic characteristics is beyond the capabilities of traditional microbiological methods

  17. Use of MgO to mitigate the effect of microbial CO2 production in the Waste Isolation Pilot Plant

    International Nuclear Information System (INIS)

    Wang, Y.; Brush, L.H.

    1997-01-01

    The Waste Isolation Pilot Plant (WIPP), located in a salt bed in southern New Mexico, is designed by US Department of Energy to demonstrate the safe and permanent disposal of design-basis transuranic waste. WIPP performance assessment requires consideration of radionuclide release in brines in the event of inadvertent human intrusion. The mobility of radionuclides depends on chemical factors such as brine pmH (-log molality of H + ) and CO 2 fugacity. According to current waste inventory estimates, a large quantity (∼ 10 9 moles C) of organic materials will be emplaced in the WIPP. Those organic material will potentially be degraded by halophilic or halotolerant microorganisms in the presence of liquid water in the repository, especially if a large volume of brine is introduced into the repository by human intrusions. Organic material biodegradation will produce a large amount of CO 2 , which will acidify the WIPP brine and thus significantly increase the mobility of actinides. This communication addresses (1) the rate of organic material biodegradation and the quantity of CO 2 to be possibly generated, (2) the effect of microbial CO 2 production on overall WIPP performance, and (3) the mechanism of using MgO to mitigate this effect

  18. A general method for selection of riboflavin-overproducing food grade micro-organisms

    OpenAIRE

    Burgess, Catherine M; Smid, Eddy J; Rutten, Ger; van Sinderen, Douwe

    2006-01-01

    Abstract Background This study describes a strategy to select and isolate spontaneous riboflavin-overproducing strains of Lactobacillus (Lb.) plantarum, Leuconostoc (Lc.) mesenteroides and Propionibacterium (P.) freudenreichii. Results The toxic riboflavin analogue roseoflavin was used to isolate natural riboflavin-overproducing variants of the food grade micro-organisms Lb. plantarum, Lc. mesenteroides and P. freudenreichii strains. The method was successfully employed for strains of all thr...

  19. Isolation of gallic acid-producing microorganisms and their use in ...

    African Journals Online (AJOL)

    A total number of eighty gallic acid producing strains were isolated from forest soil or plant samples. Among these strains, thirteen isolates were selected for gallic acid production and these isolates were Aspergillus niger 1, A. niger 2, A. niger 3, Penicillium canescens (3), P. frequentans (2), P. spinulosum (2), ...

  20. Proteomic characterization of the outer membrane vesicle of the halophilic marine bacterium Novosphingobium pentaromativorans US6-1.

    Science.gov (United States)

    Yun, Sung Ho; Lee, Sang-Yeop; Choi, Chi-Won; Lee, Hayoung; Ro, Hyun-Joo; Jun, Sangmi; Kwon, Yong Min; Kwon, Kae Kyoung; Kim, Sang-Jin; Kim, Gun-Hwa; Kim, Seung Il

    2017-01-01

    Novosphingobium pentaromativorans US6-1 is a Gram-negative halophilic marine bacterium able to utilize several polycyclic aromatic hydrocarbons such as phenanthrene, pyrene, and benzo[a]pyrene. In this study, using transmission electron microscopy, we confirmed that N. pentaromativorans US6-1 produces outer membrane vesicles (OMVs). N. pentaromativorans OMVs (hereafter OMV Novo ) are spherical in shape, and the average diameter of OMV Novo is 25-70 nm. Proteomic analysis revealed that outer membrane proteins and periplasmic proteins of N. pentaromativorans are the major protein components of OMV Novo . Comparative proteomic analysis with the membrane-associated protein fraction and correlation analysis demonstrated that the outer membrane proteins of OMV Novo originated from the membrane- associated protein fraction. To the best of our knowledge, this study is the first to characterize OMV purified from halophilic marine bacteria.

  1. Effects of temperature on biological activity of permafrost microorganisms.

    Science.gov (United States)

    Kalyonova, L F; Novikova, M A; Subbotin, A M; Bazhin, A S

    2015-04-01

    The number and viability of microorganism specimens Bacillus spp. isolated from permafrost soil remained unchanged after incubation at temperatures of -16-37°C. Experiments on F1 CBA/Black-6 mice showed that incubation of bacteria at -5°C for 72 h promotes a decrease in their toxicity and an increase in their immunostimulating effect.

  2. [Increasing incidence of community-acquired pneumonia caused by atypical microorganisms].

    Science.gov (United States)

    Tazón-Varela, M A; Alonso-Valle, H; Muñoz-Cacho, P; Gallo-Terán, J; Piris-García, X; Pérez-Mier, L A

    2017-09-01

    Knowing the most common microorganisms in our environment can help us to make proper empirical treatment decisions. The aim is to identify those microorganisms causing community-acquired pneumonia. An observational, descriptive and prospective study was conducted, including patients over 14 years with a clinical and radiographic diagnosis of community-acquired pneumonia during a 383 consecutive day period. A record was made of sociodemographic variables, personal history, prognostic severity scales, progress, and pathogenic agents. The aetiological diagnosis was made using blood cultures, detection of Streptococcus pneumoniae and Legionella pneumophila urinary antigens, sputum culture, influenza virus and Streptococcus pyogenes detection. Categorical variables are presented as absolute values and percentages, and continuous variables as their means and standard deviations. Of the 287 patients included in the study (42% women, mean age 66±22 years), 10.45% died and 70% required hospital admission. An aetiological diagnosis was achieved in 43 patients (14.98%), with 16 microorganisms found in 59 positive samples. The most frequently isolated pathogen was Streptococcus pneumonia (24/59, 41%), followed by gram-negative enteric bacilli, Klebsiella pneumonia, Escherichia coli, Serratia marcescens and Enterobacter cloacae isolated in 20% of the samples (12/59), influenza virus (5/59, 9%), methicillin-resistant Staphylococcus aureus (3/59, 5%), Pseudomonas aeruginosa (2/59, 3%), Moraxella catarrhalis (2/59, 3%), Legionella pneumophila (2/59, 3%), and Haemophilus influenza (2/59, 3%). Polymicrobial infections accounted for 14% (8/59). A high percentage of atypical microorganisms causing community-acquired pneumonia were found. Copyright © 2016 Sociedad Española de Médicos de Atención Primaria (SEMERGEN). Publicado por Elsevier España, S.L.U. All rights reserved.

  3. Molecular Identification of Microorganisms Associated to the Rhizosphere of Vanilla Plants in Colombia

    OpenAIRE

    Claudia Lucía Álvarez López; Nelson Walter Osorio Vega; Mauricio Alejandro Marín Montoya

    2013-01-01

    The cultivation of vanilla (Vanilla planifolia) is highly promising in Colombia, but more research is needed on its agronomical management and beneficial microorganisms that grow associated to its rhizosphere, on which the plant depends for its nutrition and growth. This study involved the identification of microorganisms associated to the rhizosphere of vanilla plants in a crop located in Sopetrán, Colombia. The microbes were isolated in selective media for functional groups such as cellulol...

  4. Adaptation and monitoring of microorganisms in petroleum industry wastewater nitrification processes

    Directory of Open Access Journals (Sweden)

    A. Madero

    1998-07-01

    Full Text Available Biological removal of ammonia nitrogen is carried out in two successive stages, nitrification and denitrification. This work studied the nitrification process on microorganisms isolated from different aquifer sources: a eutrophicate pond and residual waters from two treatment plants (petrochemical and domestic

  5. Two new sesquiterpenoids produced by halophilic Nocardiopsis chromatogenes YIM 90109.

    Science.gov (United States)

    Sun, Ming-Wei; Zhang, Xiao-Mei; Bi, Hui-Li; Li, Wen-Jun; Lu, Chun-Hua

    2017-01-01

    Two new germacradiene-type sesquiterpenoids, including 1(10)E,5E-germacradiene-9β,11-diol (or 9β-hydroxyl germacradienol) (1) and 11-hydroxy-1(10)E,5E-germacradien-2-one (2-oxygermacradienol) (2), together with a known geosmin-type sesquiterpenoid (1β,4β,4aβ,7α,8aα)-4,8a-dimethyloctahydronaphthalene-1,4a,7(2H)-triol (3), were elucidated by their NMR spectroscopic data, HR-ESI-MS and single-crystal X-ray diffraction from the halophilic strain Nocardiopsis chromatogenes YIM 90109. The antimicrobial activities were evaluated by paper diffusion method.

  6. Compost supplementation with nutrients and microorganisms in composting process.

    Science.gov (United States)

    Sánchez, Óscar J; Ospina, Diego A; Montoya, Sandra

    2017-11-01

    The composting is an aerobic, microorganism-mediated, solid-state fermentation process by which different organic materials are transformed into more stable compounds. The product obtained is the compost, which contributes to the improvement of physical, chemical and microbiological properties of the soil. However, the compost usage in agriculture is constrained because of its long-time action and reduced supply of nutrients to the crops. To enhance the content of nutrients assimilable by the plants in the compost, its supplementation with nutrients and inoculation with microorganisms have been proposed. The objective of this work was to review the state of the art on compost supplementation with nutrients and the role played by the microorganisms involved (or added) in their transformation during the composting process. The phases of composting are briefly compiled and different strategies for supplementation are analyzed. The utilization of nitrogenous materials and addition of microorganisms fixing nitrogen from the atmosphere or oxidizing ammonia into more assimilable for plants nitrogenous forms are analyzed. Several strategies for nitrogen conservation during composting are presented as well. The supplementation with phosphorus and utilization of microorganisms solubilizing phosphorus and potassium are also discussed. Main groups of microorganisms relevant during the composting process are described as well as most important strategies to identify them. In general, the development of this type of nutrient-enriched bio-inputs requires research and development not only in the supplementation of compost itself, but also in the isolation and identification of microorganisms and genes allowing the degradation and conversion of nitrogenous substances and materials containing potassium and phosphorus present in the feedstocks undergoing the composting process. In this sense, most important research trends and strategies to increase nutrient content in the compost

  7. Identification of Microorganisms by Modern Analytical Techniques.

    Science.gov (United States)

    Buszewski, Bogusław; Rogowska, Agnieszka; Pomastowski, Paweł; Złoch, Michał; Railean-Plugaru, Viorica

    2017-11-01

    Rapid detection and identification of microorganisms is a challenging and important aspect in a wide range of fields, from medical to industrial, affecting human lives. Unfortunately, classical methods of microorganism identification are based on time-consuming and labor-intensive approaches. Screening techniques require the rapid and cheap grouping of bacterial isolates; however, modern bioanalytics demand comprehensive bacterial studies at a molecular level. Modern approaches for the rapid identification of bacteria use molecular techniques, such as 16S ribosomal RNA gene sequencing based on polymerase chain reaction or electromigration, especially capillary zone electrophoresis and capillary isoelectric focusing. However, there are still several challenges with the analysis of microbial complexes using electromigration technology, such as uncontrolled aggregation and/or adhesion to the capillary surface. Thus, an approach using capillary electrophoresis of microbial aggregates with UV and matrix-assisted laser desorption ionization time-of-flight MS detection is presented.

  8. Production and characterization of a biodegradable poly (hydroxybutyrate-co-hydroxyvalerate) (PHB-co-PHV) copolymer by moderately haloalkalitolerant Halomonas campisalis MCM B-1027 isolated from Lonar Lake, India.

    Science.gov (United States)

    Kulkarni, S O; Kanekar, P P; Nilegaonkar, S S; Sarnaik, S S; Jog, J P

    2010-12-01

    Several microorganisms produce polyhydroxyalkanoates (PHA). They are accumulated intracellularly as energy storage compounds. The PHAs are of interest because of their potential in biomedical applications. Halophilic bacteria and archaea are known to produce polyhydroxybutyrate (PHB). This paper describes production of a biodegradable copolymer, PHB-co-PHV by a moderately haloalkalitolerant Halomonas campisalis, isolated from Lonar Lake, India. The production of PHA was in the range of 45-81% on dry cell weight basis when the organism was grown in a production medium containing 1% (w/v) maltose and 0.1% (w/v) yeast extract, at pH ranging from 6 to 9 with an inoculum density of 10(5)-10(7) cells/ml of medium, for incubation period of 15-30 h and at 37 degrees C. The polymer produced by the organism is a hydroxyester with molecular weight of 1.3014 x 10(6). Its melting temperature was 171 degrees C. The (1)H NMR analysis revealed that the polymer was a copolymer of PHB-co-PHV. This could be achieved by providing simple carbon source viz. maltose. Copyright (c) 2010 Elsevier Ltd. All rights reserved.

  9. Characterization of a halophilic heterotrophic nitrification-aerobic denitrification bacterium and its application on treatment of saline wastewater.

    Science.gov (United States)

    Duan, Jinming; Fang, Hongda; Su, Bing; Chen, Jinfang; Lin, Jinmei

    2015-03-01

    A novel halophilic bacterium capable of heterotrophic nitrification-aerobic denitrification was isolated from marine sediments and identified as Vibrio diabolicus SF16. It had ability to remove 91.82% of NH4(+)-N (119.77 mg/L) and 99.71% of NO3(-)-N (136.43 mg/L). The nitrogen balance showed that 35.83% of initial NH4(+)-N (119.77 mg/L) was changed to intracellular nitrogen, and 53.98% of the initial NH4(+)-N was converted to gaseous denitrification products. The existence of napA gene further proved the aerobic denitrification ability of strain SF16. The optimum culture conditions were salinity 1-5%, sodium acetate as carbon source, C/N 10, and pH 7.5-9.5. When an aerated biological filter system inoculated with strain SF16 was employed to treat saline wastewater, the average removal efficiency of NH4(+)-N and TN reached 97.14% and 73.92%, respectively, indicating great potential of strain SF16 for future full-scale applications. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. DNA Binding in High Salt: Analysing the Salt Dependence of Replication Protein A3 from the Halophile Haloferax volcanii

    Directory of Open Access Journals (Sweden)

    Jody A. Winter

    2012-01-01

    Full Text Available Halophilic archaea maintain intracellular salt concentrations close to saturation to survive in high-salt environments and their cellular processes have adapted to function under these conditions. Little is known regarding halophilic adaptation of the DNA processing machinery, particularly intriguing since protein-DNA interactions are classically salt sensitive. To investigate such adaptation, we characterised the DNA-binding capabilities of recombinant RPA3 from Haloferax volcanii (HvRPA3. Under physiological salt conditions (3 M KCl, HvRPA3 is monomeric, binding 18 nucleotide ssDNA with nanomolar affinity, demonstrating that RPAs containing the single OB-fold/zinc finger architecture bind with broadly comparable affinity to two OB-fold/zinc finger RPAs. Reducing the salt concentration to 1 M KCl induces dimerisation of the protein, which retains its ability to bind DNA. On circular ssDNA, two concentration-dependent binding modes are observed. Conventionally, increased salt concentration adversely affects DNA binding but HvRPA3 does not bind DNA in 0.2 M KCl, although multimerisation may occlude the binding site. The single N-terminal OB-fold is competent to bind DNA in the absence of the C-terminal zinc finger, albeit with reduced affinity. This study represents the first quantitative characterisation of DNA binding in a halophilic protein in extreme salt concentrations.

  11. Potentially pathogenic amoeba-associated microorganisms in cooling towers and their control.

    Science.gov (United States)

    Pagnier, Isabelle; Merchat, Michèle; La Scola, Bernard

    2009-06-01

    Cooling towers provide a favorable environment for the proliferation of microorganisms. Cooling towers generate a biofilm and often aerosolize contaminated water, thereby increasing the risk of microorganism dissemination by human inhalation. This pathogen dissemination was first revealed by the epidemics of Legionnaires' disease that were directly related to the presence of cooling towers, and since then, the ecology of Legionella pneumophila has been well studied. Each country has specific standards regarding the acceptable amount of microorganisms in cooling tower systems. However, those standards typically only concern L. pneumophila, even though many other microorganisms can also be isolated from cooling towers, including protozoa, bacteria and viruses. Microbiological control of the cooling tower system can be principally achieved by chemical treatments and also by improving the system's construction. Several new treatments are being studied to improve the efficiency of disinfection. However, as most of these treatments continue to focus solely on L. pneumophila, reports of other types of pathogens continue to increase. Therefore, how their dissemination affects the human populous health should be addressed now.

  12. Monitoring of psychrotrophic microorganisms in raw milk

    Directory of Open Access Journals (Sweden)

    Radka Burdychová

    2008-01-01

    Full Text Available The group of psychrotrophic microorganisms belongs to the microorganisms representing a risk for human health as well as a risk of milk and milk products spoilage. Some genus are considered to be significant producers of proteolytic and lipolytic enzymes. In this work, we analysed raw milk samples (n = 109 originated from 26 different suppliers from the area of North and Middle Moravia. The screening was performed from March 2007 to February 2008. The total bacterial counts (TBC ranged between 3.2 × 103 to 8.3 × 106 CFU/ml. The psychrotrophic bacterial counts (PBC ranged between 1.0 × 103 to 8.2 × 106 CFU/ml. Total of 48.62 % and 48.62 % of samples exceeded the hygienic limit in raw milk for TBC and PBC, respectively. The correlation between TBC and PBC was highly significant (r = 0.87.Significantly higher (P < 0.05 numbers of psychrotrophic microorganisms were detected in summer months. The identification of isolates was carried out and all strains were sreened for ability to produce proteolytic and lipolytic enzymes. The most commonly identified genus in raw milk was of the genus Pseudomonas. The ability to produce proteases or lipases was found at 76 % identified bacterial strains.

  13. Selection of mesophilic microorganisms with biodesulfuration capacity

    International Nuclear Information System (INIS)

    Madero, A; Mogollon, L. I; Mora, A.L; Osorio, L.F

    1998-01-01

    The development of bio desulfurization (BDS) processes for hydrocarbons requires fast and reliable methods for the screening of microorganisms. This work shows the results of the screening process for indigenous Colombian strains with a BDS potential capacity. The main criteria for the screening were the qualitative and quantitative determination of 2-hydroxybiphenyl (2-HBP) as the typical metabolite of the 4S specific pathway. Microorganisms were cultured by two methodologies, A and B, using DBT as the model compound. The quantitative determination of metabolites was made by HPLC. Thirteen strains were evaluated, including the strain Rhodococcus rhodocrous IGTS8, by methods A and B. In method A, the inoculum was exposed to DBT since the beginning of the culture. Method B, employed two stages: (i) Growth period under limiting sulfur conditions, (ii) Transforming period, in which the pre-grown inoculum was exposed to the organic sulfur substrate. The culture of mesophilic microorganisms isolated by method B, served to find a mechanism for the organic sulfur metabolism, and the evaluation of the sulfur removal capability of five indigenous strains. In the cultures of these strains, 2- hydroxybiphenyl (2-HBP) was detected as a byproduct of DBT metabolism, both qualitatively and quantitatively

  14. Micro-Organ Device

    Science.gov (United States)

    Gonda, Steve R. (Inventor); Chang, Robert C. (Inventor); Starly, Binil (Inventor); Culbertson, Christopher (Inventor); Holtorf, Heidi L. (Inventor); Sun, Wei (Inventor); Leslie, Julia (Inventor)

    2013-01-01

    A method for fabricating a micro-organ device comprises providing a microscale support having one or more microfluidic channels and one or more micro-chambers for housing a micro-organ and printing a micro-organ on the microscale support using a cell suspension in a syringe controlled by a computer-aided tissue engineering system, wherein the cell suspension comprises cells suspended in a solution containing a material that functions as a three-dimensional scaffold. The printing is performed with the computer-aided tissue engineering system according to a particular pattern. The micro-organ device comprises at least one micro-chamber each housing a micro-organ; and at least one microfluidic channel connected to the micro-chamber, wherein the micro-organ comprises cells arranged in a configuration that includes microscale spacing between portions of the cells to facilitate diffusion exchange between the cells and a medium supplied from the at least one microfluidic channel.

  15. Immobilization of halophilic Bacillus sp. EMB9 protease on functionalized silica nanoparticles and application in whey protein hydrolysis.

    Science.gov (United States)

    Sinha, Rajeshwari; Khare, S K

    2015-04-01

    The present work targets the fabrication of an active, stable, reusable enzyme preparation using functionalized silica nanoparticles as an effective enzyme support for crude halophilic Bacillus sp. EMB9 protease. The immobilization efficiency under optimized conditions was 60%. Characterization of the immobilized preparation revealed marked increase in pH and thermal stability. It retained 80% of its original activity at 70 °C while t 1/2 at 50 °C showed a five-fold enhancement over that for the free protease. Kinetic constants K m and V max were indicative of a higher reaction velocity along with decreased affinity for substrate. The preparation could be efficiently reused up to 6 times and successfully hydrolysed whey proteins with high degree of hydrolysis. Immobilization of a crude halophilic protease on a nanobased scaffold makes the process cost effective and simple.

  16. Sulfide Generation by Dominant Halanaerobium Microorganisms in Hydraulically Fractured Shales

    Energy Technology Data Exchange (ETDEWEB)

    Booker, Anne E.; Borton, Mikayla A.; Daly, Rebecca A.; Welch, Susan A.; Nicora, Carrie D.; Hoyt, David W.; Wilson, Travis; Purvine, Samuel O.; Wolfe, Richard A.; Sharma, Shikha; Mouser, Paula J.; Cole, David R.; Lipton, Mary S.; Wrighton, Kelly C.; Wilkins, Michael J.; McMahon, Katherine

    2017-07-05

    ABSTRACT

    Hydraulic fracturing of black shale formations has greatly increased United States oil and natural gas recovery. However, the accumulation of biomass in subsurface reservoirs and pipelines is detrimental because of possible well souring, microbially induced corrosion, and pore clogging. Temporal sampling of produced fluids from a well in the Utica Shale revealed the dominance ofHalanaerobiumstrains within thein situmicrobial community and the potential for these microorganisms to catalyze thiosulfate-dependent sulfidogenesis. From these field data, we investigated biogenic sulfide production catalyzed by aHalanaerobiumstrain isolated from the produced fluids using proteogenomics and laboratory growth experiments. Analysis ofHalanaerobiumisolate genomes and reconstructed genomes from metagenomic data sets revealed the conserved presence of rhodanese-like proteins and anaerobic sulfite reductase complexes capable of converting thiosulfate to sulfide. Shotgun proteomics measurements using aHalanaerobiumisolate verified that these proteins were more abundant when thiosulfate was present in the growth medium, and culture-based assays identified thiosulfate-dependent sulfide production by the same isolate. Increased production of sulfide and organic acids during the stationary growth phase suggests that fermentativeHalanaerobiumuses thiosulfate to remove excess reductant. These findings emphasize the potential detrimental effects that could arise from thiosulfate-reducing microorganisms in hydraulically fractured shales, which are undetected by current industry-wide corrosion diagnostics.

    IMPORTANCEAlthough thousands of wells in deep shale formations across the United States have been hydraulically fractured for oil and gas recovery, the impact of microbial metabolism within these environments is poorly understood. Our

  17. Identification and Characterization of Extremophile Microorganisms with Significance to Astrobiology

    Science.gov (United States)

    Bej, Asim K.

    2003-01-01

    It is now well recognized that microorganisms thrive in extreme ecological conditions such as geothermal vents, polar region, acid and alkaline lakes, and the cold pressurized depth of the ocean floor of this planet. Morphological, physiological, biochemical and genetic adaptations to extreme environments by these extremophile microorganisms have generated immense interest amongst astrobiologists who increasingly believe in the existence of extraterrestrial life. The evidence collected by NASA's space probe Galileo suggested the presence of liquid water and volcanic activity on Mars and Jupiter's satellite Europa. Volcanic activity provides some of the heat necessary to keep the water on Europa from freezing that could provide important dissolved chemicals needed by living organisms. The possibility of the existence of hypersaline alkaline lakes and evaporites confined within closed volcanic basins and impact craters on Mars, and a layer of liquid water under the ice on Europa provide sufficient 'raison d'etre' to study microorganisms in similar extreme environments on Earth, which could provide us with a model that would help establish the existence of extraterrestrial life on other planetary bodies. The objectives of the summer research project were as follows: (1) application of molecular approaches to help establish new species of extremophile microorganisms isolated from a hypersaline alkaline lake; and (2) identification of a major cold-shock gene (cspA) homolog from a psychrotolerant microorganism, PmagG1.

  18. Isolation of antimicrobial producing Actinobacteria from soil samples.

    Science.gov (United States)

    Elbendary, Afaf Ahmed; Hessain, Ashgan Mohamed; El-Hariri, Mahmoud Darderi; Seida, Ahmed Adel; Moussa, Ihab Mohamed; Mubarak, Ayman Salem; Kabli, Saleh A; Hemeg, Hassan A; El Jakee, Jakeen Kamal

    2018-01-01

    Emergence of multidrug resistant bacteria has made the search for novel bioactive compounds from natural and unexplored habitats a necessity. Actinobacteria have important bioactive substances. The present study investigated antimicrobial activity of Actinobacteria isolated from soil samples of Egypt. One hundred samples were collected from agricultural farming soil of different governorates. Twelve isolates have produced activity against the tested microorganisms ( S. aureus , Bacillus cereus , E. coli , K. pneumoniae , P. aeruginosa , S. Typhi, C. albicans , A. niger and A. flavus ). By VITEK 2 system version: 07.01 the 12 isolates were identified as Kocuria kristinae , Kocuria rosea , Streptomyces griseus , Streptomyces flaveolus and Actinobacteria . Using ethyl acetate extraction method the isolates culture's supernatants were tested by diffusion method against indicator microorganisms. These results indicate that Actinobacteria isolated from Egypt farms could be sources of antimicrobial bioactive substances.

  19. Growth response of microorganisms to different molecular fractions of lignite

    Energy Technology Data Exchange (ETDEWEB)

    Polman, J.K.; Breckenridge, C.R.; Dugan, P.R.; Quigley, D.R.

    1990-01-01

    Our research is primarily concerned with isolating and characterizing microbes which are able to dissimilate coal and convert it to other useful chemicals. This quarter, general growth responses of microorganisms cultivated in the presence of different molecular weight fractions of lignite coal were examined. Aerobic and anaerobic environmental samples from a variety of ecological niches were used as inocula. Growth of the microorganisms in these samples on the following types of media was tested: COAL medium, containing alkali-solubilized whole coal; THFI medium, containing the alkali-solubilized, tetrahydrofuran-insoluble, macromolecular portion of whole coal; THFS medium, containing the THF-soluble, low molecular weight portion of whole coal; and CON medium, void of any coal constituent. Overall results indicated that the presence of the THF-soluble, low molecular weight coal fraction enhanced the growth yield and the variety of aerobic microorganisms compared to the other coal fractions or the control medium. Conversely, anaerobic microbes grew best on media which contained the macromolecular fraction. 12 refs., 5 tabs.

  20. The Characterization of Psychrophilic Microorganisms and their potentially useful Cold-Active Glycosidases Final Progress Report

    Energy Technology Data Exchange (ETDEWEB)

    Brenchly, Jean E.

    2008-06-30

    Our studies of novel, cold-loving microorganisms have focused on two distinct extreme environments. The first is an ice core sample from a 120,000 year old Greenland glacier. The results of this study are particularly exciting and have been highlighted with press releases and additional coverage. The first press release in 2004 was based on our presentation at the General Meeting of the American Society for Microbiology and was augmented by coverage of our publication (Appl. Environ. Microbiol. 2005. Vol. 71:7806) in the Current Topics section of the ASM news journal, “Microbe.” Of special interest for this report was the isolation of numerous, phylogenetically distinct and potentially novel ultrasmall microorganisms. The detection and isolation of members of the ultrasmall population is significant because these cells pass through 0.2 micron pore filters that are generally used to trap microorganisms from environmental samples. Thus, analyses by other investigators that examined only cells captured on the filters would have missed a significant portion of this population. Only a few ultrasmall isolates had been obtained prior to our examination of the ice core samples. Our development of a filtration enrichment and subsequent cultivation of these organisms has added extensively to the collection of, and knowledge about, this important population in the microbial world.

  1. Antimicrobial Susceptibility of Microorganisms Isolated from Orofacial Infections

    Directory of Open Access Journals (Sweden)

    Sinan TOZOĞLU

    2010-05-01

    Full Text Available Objectives: The purpose of this study was to determine an effective antimicrobial therapy ofcausative agents for orofacial abscesses. In order to do that, bacterial strains isolated from patientsamples were identified based on “bacterial fatty acid profiles” and determined the antimicrobialsusceptibilities by using disc diffusion test for aerobic bacteria, and E test for anaerobic bacteria.Materials and Methods: The present study was carried out in 71 patients with a diagnosis oforofacial infections in Oral and Maxillofacial Surgery Clinic of Atatürk University. Aerobic andanaerobic bacteria were isolated from 71 clinical specimens by Microbial Identification Systemand their antibiotic sensitivity was tested. Results: The most frequently isolated species were Streptococcus spp., Staphylococcus spp.and Bacteroides spp. The highest rate of resistance was detected in the aerobic strains againstpenicillin (58.4%, followed by eriythromycin (46.7%, clindamycin (35.1%, tetracycline(32.5%, amoxycillin/clavulonic acid (31.1% and cefazoline (27.3%, respectively. The highestrate of resistance was detected in the anaerobic strains against to penicillin (60%, clindamycin(53.3%, metronidazole (30%, cefoxitin (20% piperacillin/tazobactam (11.6% and imipenem(0.3%, respectively. Conclusions: In order to treat orofacial infections more effectively, and to prevent antimicrobialresistance which has increased recently, antibiotic susceptility tests should be performedroutinely in regions where antibacterial resistance is high like our area.

  2. Identification of beer spoilage microorganisms using the MALDI Biotyper platform.

    Science.gov (United States)

    Turvey, Michelle Elizabeth; Weiland, Florian; Meneses, Jon; Sterenberg, Nick; Hoffmann, Peter

    2016-03-01

    Beer spoilage microorganisms present a major risk for the brewing industry and can lead to cost-intensive recall of contaminated products and damage to brand reputation. The applicability of molecular profiling using matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOF MS) in combination with Biotyper software was investigated for the identification of beer spoilage microorganisms from routine brewery quality control samples. Reference mass spectrum profiles for three of the most common bacterial beer spoilage microorganisms (Lactobacillus lindneri, Lactobacillus brevis and Pediococcus damnosus), four commercially available brewing yeast strains (top- and bottom-fermenting) and Dekkera/Brettanomyces bruxellensis wild yeast were established, incorporated into the Biotyper reference library and validated by successful identification after inoculation into beer. Each bacterial species could be accurately identified and distinguished from one another and from over 5600 other microorganisms present in the Biotyper database. In addition, wild yeast contaminations were rapidly detected and distinguished from top- and bottom-fermenting brewing strains. The applicability and integration of mass spectrometry profiling using the Biotyper platform into existing brewery quality assurance practices within industry were assessed by analysing routine microbiology control samples from a local brewery, where contaminating microorganisms could be reliably identified. Brewery-isolated microorganisms not present in the Biotyper database were further analysed for identification using LC-MS/MS methods. This renders the Biotyper platform a promising candidate for biological quality control testing within the brewing industry as a more rapid, high-throughput and cost-effective technology that can be tailored for the detection of brewery-specific spoilage organisms from the local environment.

  3. Changes in Gram Negative Microorganisms' Resistance Pattern During 4 Years Period in a Referral Teaching Hospital; a Surveillance Study

    Directory of Open Access Journals (Sweden)

    Hossein Khalili

    2012-09-01

    Full Text Available Background and purpose Surveillance studies evaluating antimicrobial susceptibilities are of great value in preventing the spread of resistant pathogens by elucidating the trend of resistance in commonly used antibiotics and as a consequence providing information for prescribing the most appropriate agent. This study is a longitudinal antimicrobial resistance surveillance study designed to evaluate the trend in antimicrobial resistance to gram negative microorganisms from 2007 to 2010. Method:During a four-year period (2007-2010 isolates derived from all patients admitted to infectious diseases ward of Imam Khomeini Hospital, the major referral center for infectious disease in Iran with the highest admission rates, were evaluated. Based on disk diffusion method and zone of inhibition size, the microorganism was regarded as to be sensitive, resistant or has intermediate susceptibility to the antimicrobial agents. Results:The widest spread Gram-negative microorganism in all of isolates taken together in our study was E.coli (30% followed by Stenotrophomonas maltophilia in 28.6% and Enterobacter spp. in 11.9%, respectively. The susceptibility to amikacin, imipenem, piperacillin/tazobactam, and nitrofurantoin was equal or above 50% for all microorganisms over four years. However, the susceptibility to ampicillin, ampicillin/sulbactam, cefotaxim, and ceftriaxone was less than 50% in derived isolates during the study period.Conclusion:In conclusion, the finding of the present study revealed that resistance rate to common antimicrobial agents in Iran is growing and isolates were susceptible mostly to broadspectrum antibiotics including imipenem and piperacillin/tazobactam

  4. Assessment of microorganisms from Indonesian Oil Fields

    Energy Technology Data Exchange (ETDEWEB)

    Kadarwati, S.; Udiharto, M.; Rahman, M.; Jasjfi, E.; Legowo, E.H. [Research and Development Centre for Oil and Gas Technology LEMIGAS, Jakarta Selatan (Indonesia)

    1995-12-31

    Petroleum resources have been the mainstay of the national development in Indonesia. However, resources are being depleted after over a century of exploitation, while the demand continues to grow with the rapid economic development of the country. In facing the problem, EOR has been applied in Indonesia, such as the steamflooding project in Duri field, but a more energy efficient technology would be preferable. Therefore, MEOR has been recommended as a promising solution. Our study, aimed at finding indigenous microorganisms which can be developed for application in MEOR, has isolated microbes from some oil fields of Indonesia. These microorganisms have been identified, their activities studied, and the effects of their metabolisms examined. This paper describes the research carried out by LEMIGAS in this respect, giving details on the methods of sampling, incubation, identification, and activation of the microbes as well as tests on the effects of their metabolites, with particular attention to those with potential for application in MEOR.

  5. Native carbonoxidation microorganisms in bioremedetion Northern Caspian sea from oil pollution

    Directory of Open Access Journals (Sweden)

    V. V. Gridneva

    2010-01-01

    Full Text Available The 26 strains microorganisms - degradation oil have been isolated from shelf water North Caspian. The high emulsifying ability relative to benzine, kerosene and diesel-fuel oil relevantly were possessed the 11 strains. The 4 cultures exhibiting degradation of oil rates 43-49 %, respectively, were selected.

  6. Isolation of antimicrobial producing Actinobacteria from soil samples

    Directory of Open Access Journals (Sweden)

    Afaf Ahmed Elbendary

    2018-01-01

    Full Text Available Emergence of multidrug resistant bacteria has made the search for novel bioactive compounds from natural and unexplored habitats a necessity. Actinobacteria have important bioactive substances. The present study investigated antimicrobial activity of Actinobacteria isolated from soil samples of Egypt. One hundred samples were collected from agricultural farming soil of different governorates. Twelve isolates have produced activity against the tested microorganisms (S. aureus, Bacillus cereus, E. coli, K. pneumoniae, P. aeruginosa, S. Typhi, C. albicans, A. niger and A. flavus. By VITEK 2 system version: 07.01 the 12 isolates were identified as Kocuria kristinae, Kocuria rosea, Streptomyces griseus, Streptomyces flaveolus and Actinobacteria. Using ethyl acetate extraction method the isolates culture’s supernatants were tested by diffusion method against indicator microorganisms. These results indicate that Actinobacteria isolated from Egypt farms could be sources of antimicrobial bioactive substances.

  7. Cloning and Molecular Characterization of an Alpha-Glucosidase (MalH) from the Halophilic Archaeon Haloquadratum walsbyi.

    Science.gov (United States)

    Cuebas-Irizarry, Mara F; Irizarry-Caro, Ricardo A; López-Morales, Carol; Badillo-Rivera, Keyla M; Rodríguez-Minguela, Carlos M; Montalvo-Rodríguez, Rafael

    2017-11-21

    We report the heterologous expression and molecular characterization of the first extremely halophilic alpha-glucosidase (EC 3.2.1.20) from the archaeon Haloquadratum walsbyi . A 2349 bp region ( Hqrw_2071 ) from the Hqr. walsbyi C23 annotated genome was PCR-amplified and the resulting amplicon ligated into plasmid pET28b(+), expressed in E. coli Rosetta cells, and the resulting protein purified by Ni-NTA affinity chromatography. The recombinant protein showed an estimated molecular mass of 87 kDa, consistent with the expected value of the annotated protein, and an optimal activity for the hydrolysis of α-PNPG was detected at 40 °C, and at pH 6.0. Enzyme activity values were the highest in the presence of 3 M NaCl or 3-4 M KCl. However, specific activity values were two-fold higher in the presence of 3-4 M KCl when compared to NaCl suggesting a cytoplasmic localization. Phylogenetic analyses, with respect to other alpha-glucosidases from members of the class Halobacteria, showed that the Hqr. walsbyi MalH was most similar (up to 41%) to alpha-glucosidases and alpha-xylosidases of Halorubrum . Moreover, computational analyses for the detection of functional domains, active and catalytic sites, as well as 3D structural predictions revealed a close relationship with an E. coli YicI-like alpha-xylosidase of the GH31 family. However, the purified enzyme did not show alpha-xylosidase activity. This narrower substrate range indicates a discrepancy with annotations from different databases and the possibility of specific substrate adaptations of halophilic glucosidases due to high salinity. To our knowledge, this is the first report on the characterization of an alpha-glucosidase from the halophilic Archaea, which could serve as a new model to gain insights into carbon metabolism in this understudied microbial group.

  8. Cloning and Molecular Characterization of an Alpha-Glucosidase (MalH from the Halophilic Archaeon Haloquadratum walsbyi

    Directory of Open Access Journals (Sweden)

    Mara F. Cuebas-Irizarry

    2017-11-01

    Full Text Available We report the heterologous expression and molecular characterization of the first extremely halophilic alpha-glucosidase (EC 3.2.1.20 from the archaeon Haloquadratum walsbyi. A 2349 bp region (Hqrw_2071 from the Hqr. walsbyi C23 annotated genome was PCR-amplified and the resulting amplicon ligated into plasmid pET28b(+, expressed in E. coli Rosetta cells, and the resulting protein purified by Ni-NTA affinity chromatography. The recombinant protein showed an estimated molecular mass of 87 kDa, consistent with the expected value of the annotated protein, and an optimal activity for the hydrolysis of α-PNPG was detected at 40 °C, and at pH 6.0. Enzyme activity values were the highest in the presence of 3 M NaCl or 3–4 M KCl. However, specific activity values were two-fold higher in the presence of 3–4 M KCl when compared to NaCl suggesting a cytoplasmic localization. Phylogenetic analyses, with respect to other alpha-glucosidases from members of the class Halobacteria, showed that the Hqr. walsbyi MalH was most similar (up to 41% to alpha-glucosidases and alpha-xylosidases of Halorubrum. Moreover, computational analyses for the detection of functional domains, active and catalytic sites, as well as 3D structural predictions revealed a close relationship with an E. coli YicI-like alpha-xylosidase of the GH31 family. However, the purified enzyme did not show alpha-xylosidase activity. This narrower substrate range indicates a discrepancy with annotations from different databases and the possibility of specific substrate adaptations of halophilic glucosidases due to high salinity. To our knowledge, this is the first report on the characterization of an alpha-glucosidase from the halophilic Archaea, which could serve as a new model to gain insights into carbon metabolism in this understudied microbial group.

  9. Impacts of Triclosan in Grey water on Soil Microorganisms

    International Nuclear Information System (INIS)

    Harrow, D.I; Felker, J.M; Baker, K.H

    2011-01-01

    The use of grey water for irrigation is becoming a common practice in arid regions such as the Southwestern US, the Middle East, Australia, and China. While grey water supplies nutrients to soil ecosystems, the possible impact of trace contaminants, particularly pharmaceuticals and personal care products, has not been determined. This paper examined the impact of triclosan, an antibacterial agent commonly added to consumer products, on microbial populations and microbial diversity in soil irrigated with grey water. While there was no change in the total number of heterotrophic microorganisms in the soil, both the types and the antibiotic resistance of the microorganisms were significantly influenced by triclosan. The proportion of the microbial isolates resistant to antibiotics increased while at the same time, overall diversity of the microbial community decreased.

  10. Engineering of microorganisms towards recovery of rare metal ions

    Energy Technology Data Exchange (ETDEWEB)

    Kuroda, Kouichi; Ueda, Mitsuyoshi [Kyoto Univ. (Japan). Div. of Applied Life Sciences

    2010-06-15

    The bioadsorption of metal ions using microorganisms is an attractive technology for the recovery of rare metal ions as well as removal of toxic heavy metal ions from aqueous solution. In initial attempts, microorganisms with the ability to accumulate metal ions were isolated from nature and intracellular accumulation was enhanced by the overproduction of metal-binding proteins in the cytoplasm. As an alternative, the cell surface design of microorganisms by cell surface engineering is an emerging strategy for bioadsorption and recovery of metal ions. Cell surface engineering was firstly applied to the construction of a bioadsorbent to adsorb heavy metal ions for bioremediation. Cell surface adsorption of metal ions is rapid and reversible. Therefore, adsorbed metal ions can be easily recovered without cell breakage, and the bioadsorbent can be reused or regenerated. These advantages are suitable for the recovery of rare metal ions. Actually, the cell surface display of a molybdate-binding protein on yeast led to the enhanced adsorption of molybdate, one of the rare metal ions. An additional advantage is that the cell surface display system allows high-throughput screening of protein/peptide libraries owing to the direct evaluation of the displayed protein/peptide without purification and concentration. Therefore, the creation of novel metal-binding protein/ peptide and engineering of microorganisms towards the recovery of rare metal ions could be simultaneously achieved. (orig.)

  11. Autecology of microorganisms of typical Ecuador biotopes.

    Science.gov (United States)

    Tashyrev, O B; Pidgorskyi, V S; Toro, Miguel Naranjo; Gualoto, Miguel; Gladka, G V; Tashyreva, H O; Rokitko, P V; Romanovskaya, V A

    2014-01-01

    34 strains of aerobic chemoorganotrophic microorganisms were isolated from 23 soil and plant samples selected from highland biotopes of Ecuador-Andes massif (Papallacta, 4020 m), ash at the foot of the volcano Tungurahua, mountainous jungle (La Favorita, 1600 m), as well as in humid tropic botanical garden (state Puyo, 950 m). In mountain jungle samples the high number of bacteria--10(5)-10(7) CFU/g of sample were represented by 2-5 morphotypes. In highland (4020 m) samples the bacterial counts made from 10(2) to 10(7) CFU/g of sample. The current study describes resistance of isolated strains to high salinity, UV radiation and toxic metal ions. The majority of isolated strains were halotolerant. Isolates from volcanic ash showed high resistance level to UV radiation--LD99,99 made 1000-1440 J/m2; resistance level for isolates from the soil of Puyo Botanical Garden and isolates from rock lichen (Papallacta) LD99,99 made 1160 and 800 J/m2 respectively. Strains isolated from mountain jungle (La Favorita) showed lower UV-resistance. In highland biotopes of Ecuador occurred bacteria resistant to toxic metal ions. The highest resistance to Hg2+ was shown by isolate of lichen from mountain jungle, the maximal growth concentration was 0.025 g/L; to Cr(VI)--by isolate from lichen rock massif--3,0 g/L. Correlation between metal-resistance, halotolerace and UV resistance for studied strains was not detected, probably because of different microbial cell damage/repair mechanisms under the action of these factors.

  12. Isolation of Uncultured Bacteria from Antarctica Using Long Incubation Periods and Low Nutritional Media

    Directory of Open Access Journals (Sweden)

    Andre A. Pulschen

    2017-07-01

    Full Text Available Uncultured microorganisms comprise most of the microbial diversity existing on our planet. Despite advances in environmental sequencing and single-cell genomics, in-depth studies about bacterial metabolism and screening of novel bioproducts can only be assessed by culturing microbes in the laboratory. Here we report uncultured, or recalcitrant, microorganisms from an Antarctic soil sample, using relatively simple methods: oligotrophic media, extended incubation periods, observation under stereo microscopy, and selection of slow-growing bacteria. We managed to isolate several rare microorganisms belonging to infrequently isolated or recently described genera, for example Lapillicoccus, Flavitalea, Quadrisphaera, Motilibacter, and Polymorphobacter. Additionally, we obtained isolates presenting 16S rRNA sequence similarity ranging from 92.08 to 94.46% with any other known cultured species, including two distinct isolates from the class Thermoleophilia, that although common in Antarctic soils (as identified by metagenomics, was never reported to be isolated from such samples. Our data indicates that simple methods are still useful for cultivating recalcitrant microorganisms, even when dealing with samples from extreme environments.

  13. Assessment of cellulolytic microorganisms in soils of Nevados Park, Colombia.

    Science.gov (United States)

    Avellaneda-Torres, Lizeth Manuela; Pulido, Claudia Patricia Guevara; Rojas, Esperanza Torres

    2014-01-01

    A systematized survey was conducted to find soil-borne microbes that degrade cellulose in soils from unique ecosystems, such as the Superpáramo, Páramo, and the High Andean Forest in the Nevados National Natural Park (NNNP), Colombia. These high mountain ecosystems represent extreme environments, such as high levels of solar radiation, low atmospheric pressure, and extreme daily changes in temperature. Cellulolytic activity of the microorganisms was evaluated using qualitative tests, such as growth in selective media followed by staining with congo red and iodine, and quantitative tests to determine the activity of endoglucanase, β-glucosidase, exoglucanase, and total cellulase. Microorganisms were identified using molecular markers, such as the 16S rRNA gene for bacteria and the internal transcribed spacer region (ITS) of ribosomal DNA for fungi. Multivariate statistical analysis (MVA) was used to select microorganisms with high cellulolytic capacity. A total of 108 microorganisms were isolated from the soils and, in general, the enzymatic activities of fungi were higher than those of bacteria. Our results also found that none of the organisms studied were able to degrade all the components of the cellulose and it is therefore suggested that a combination of bacteria and/or fungi with various enzymatic activities be used to obtain high total cellulolytic activity. This study gives an overview of the potential microorganism that could be used for cellulose degradation in various biotechnological applications and for sustainable agricultural waste treatment.

  14. Assessment of cellulolytic microorganisms in soils of Nevados Park, Colombia

    Directory of Open Access Journals (Sweden)

    Lizeth Manuela Avellaneda-Torres

    2014-12-01

    Full Text Available A systematized survey was conducted to find soil-borne microbes that degrade cellulose in soils from unique ecosystems, such as the Superpáramo, Páramo, and the High Andean Forest in the Nevados National Natural Park (NNNP, Colombia. These high mountain ecosystems represent extreme environments, such as high levels of solar radiation, low atmospheric pressure, and extreme daily changes in temperature. Cellulolytic activity of the microorganisms was evaluated using qualitative tests, such as growth in selective media followed by staining with congo red and iodine, and quantitative tests to determine the activity of endoglucanase, β-glucosidase, exoglucanase, and total cellulase. Microorganisms were identified using molecular markers, such as the 16S rRNA gene for bacteria and the internal transcribed spacer region (ITS of ribosomal DNA for fungi. Multivariate statistical analysis (MVA was used to select microorganisms with high cellulolytic capacity. A total of 108 microorganisms were isolated from the soils and, in general, the enzymatic activities of fungi were higher than those of bacteria. Our results also found that none of the organisms studied were able to degrade all the components of the cellulose and it is therefore suggested that a combination of bacteria and/or fungi with various enzymatic activities be used to obtain high total cellulolytic activity. This study gives an overview of the potential microorganism that could be used for cellulose degradation in various biotechnological applications and for sustainable agricultural waste treatment.

  15. Radiation resistance of some microorganisms isolated from irradiated herbs

    International Nuclear Information System (INIS)

    El-Bazza, Z.E.; Shihab, A.; Farrag, H.A.; El-Sayed, Z.G.; Mahmoud, M.I.

    1997-01-01

    Three types of Egyptian medicinal herbs, sweet marjoram, spearmint and thyme were used in this study. The tested herbs were exposed to gamma radiation doses ranging from 1.0 to 10,0 kGy. The sublethal doses of radioresistant molds ranged from 1.0 to 2.0 kGy and the sublethal doses of radioresistant bacteria ranged from 7.0 to 8.0 kGy. The radioresistant molds isolated from sweet marjoram and spearmint herbs were identified as Aspergillus, whereas that isolated from thyme was identified as Aspergillus ochraceus. The radioresistant bacteria isolated from sweet marjoram, spearmint and thyme were identified as Bacillus megaterium, B.pantothenticus and B. brevis, respectively. All the radioresistant molds exhibited an exponential response. The D 15 v alue of Asp. ochraceus was 0.33 kGy, while that of Asp. niger were 0.45 and 0.5 kGy, respectively. All the bacterial species exhibited non-exponential response. The D 10 -values for B.megaterium, B. pantothenticus and B. brevis were found to be 2.58, 3.0 and 1.63 kGy, respectively

  16. Radionuclides of foods in Japan and uptake of radio/stable elements by terrestrial food, microorganism

    International Nuclear Information System (INIS)

    Sugiyama, H.; Kuwahara, C.; Kato, F.

    2004-01-01

    According to our recent investigation from 2000 to 2003, radiocesium concentrations of foods in Japan imported from various foreign countries were low levels ( 137 Cs concentrations. And also, we obtained the data that wild mushrooms collected from four points of Japanese forests in 2002 had been still contaminated by 137 Cs ( 137 Cs to mushrooms is both a direct path way from soil and an indirect path way from the cells of soil microorganisms. We performed the culture experiments of the saprophytic edible mushroom (Pleurotus otsreatus) mycelia and one of the representative soil microorganisms isolated from wild mushroom substrata, using several stable elements. On the isolation of soil microorganisms from mushroom substrata, the appearance frequencies of planktonic bacteria and filamentous actinomycetes were affected by pH of isolation medium. Cs tolerance of the planktonic bacteria and the filamentous actinomycetes showed considerable difference; as far as tested 13 soil samples, planktonic bacteria being able to grow in the presence of 50 mM CsCl were present in all the samples at a higher density but no filamentous actinomycetes could grow in the presence of 50 mM. Accumulation of Cs in filamentous actinomycetes (Streptomyces sp. K202) were two to eight times higher than those in bacteria when they were incubated in the presence of 5 mM CsCl. (author)

  17. Draft Genome Sequence of the Polyextremophilic Halorubrum sp. Strain AJ67, Isolated from Hyperarsenic Lakes in the Argentinian Puna

    OpenAIRE

    Burguener, Germán Federico; Maldonado, Marcos Javier; Revale, Santiago; Fernández Do Porto, Darío Augusto; Rascovan, Nicolas; Vazquez, Martin Pablo; Farias, Maria Eugenia; Marti, Marcelo Adrian; Turjanski, Adrian

    2016-01-01

    Halorubrum sp. AJ67, an extreme halophilic, UV resistant archae that was isolated from Laguna Antofalla in the Argentinean Puna. The draft genome sequence suggests potent enzyme candidates that are essential to survive in multiple environmental extreme conditions, as high UV radiation, elevated salinity and the presence of critical arsenic concentration. Fil: Burguener, Germán Federico. Facultad de Ciencias Exactas y Naturales. Instituto de Cálculo. Plataforma de Bioinformática Argentina; ...

  18. Antibiotic producing microorganisms from River Wiwi, Lake Bosomtwe and the Gulf of Guinea at Doakor Sea Beach, Ghana

    Directory of Open Access Journals (Sweden)

    Tawiah Adelaide A

    2012-10-01

    Full Text Available Abstract Background Microorganisms have provided a wealth of metabolites with interesting activities such as antimicrobial, antiviral and anticancer. In this study, a total of 119 aquatic microbial isolates from 30 samples (taken from water bodies in Ghana were screened by the agar-well diffusion method for ability to produce antibacterial-metabolites. Results Antibacterial activity was exhibited by 27 of the isolates (14 bacteria, 9 actinomycetes and 4 fungi against at least one of the indicator microorganisms: Enterococcus faecalis (ATCC 29212, Bacillus thuringiensis (ATCC 13838, Pseudomonas aeruginosa (ATCC 27853, Staphylococcus aureus (ATCC 25923, Proteus vulgaris (NCTC 4635 and Bacillus Subtilis (NCTC 10073. A sea isolate MAI2 (identified as a strain of Pseudomonas aeruginosa exhibited the highest antibacterial activity (lowest zone of inhibition = 22 mm. The metabolites of MAI2 extracted with chloroform were stable to heat and gave minimum inhibitory concentrations ranging between 250 and 2000 μg/ml. Bioautography of the extract revealed seven active components. Conclusion This study has therefore uncovered the potential of water bodies in the West African sub-region as reservoirs of potent bioactive metabolite producing microorganisms.

  19. Halolactibacillus halophilus gen. nov., sp. nov. and Halolactibacillus miurensis sp. nov., halophilic and alkaliphilic marine lactic acid bacteria constituting a phylogenetic lineage in Bacillus rRNA group 1.

    Science.gov (United States)

    Ishikawa, Morio; Nakajima, Kazuyuki; Itamiya, Yuko; Furukawa, Sayumi; Yamamoto, Yasushi; Yamasato, Kazuhide

    2005-11-01

    Eleven novel strains of marine-inhabiting lactic acid bacteria that were isolated from living and decaying marine organisms collected from a temperate area of Japan are described. The isolates were motile with peritrichous flagella and non-sporulating. They lacked catalase, quinones and cytochromes. Fermentation products from glucose were lactate, formate, acetate and ethanol. Lactate yield as percentage conversion from glucose was affected by the pH of the fermentation medium: approximately 55 % at the optimal growth pH of 8.0, greater than approximately 70 % at pH 7.0 and less than approximately 30 % at pH 9.0. The molar ratio of the other three products was the same at each cultivation pH, approximately 2 : 1 : 1. Carbohydrates and related compounds were aerobically metabolized to acetate and pyruvate as well as lactate. The isolates were slightly halophilic, highly halotolerant and alkaliphilic. The optimum NaCl concentration for growth was 2.0-3.0 % (w/v), with a range of 0-25.5 %. The optimum pH for growth was 8.0-9.5, with a range of 6.0-10.0. The G+C content of the DNA was 38.5-40.7 mol%. The isolates constituted two genomic species (DNA-DNA relatedness of less than 41 %) each characterized by sugar fermentation profiles. The cell-wall peptidoglycan of both phenotypes contained meso-diaminopimelic acid. The major cellular fatty acids were C(16 : 0) and a-C(13 : 0). Comparative sequence analysis of the 16S rRNA genes revealed that these isolates represent novel species constituting a phylogenetic unit outside the radiation of typical lactic acid bacteria and an independent line of descent within the group composed of the halophilic/halotolerant/alkaliphilic and/or alkalitolerant species in Bacillus rRNA group 1, with 94.8-95.1 % similarity to the genus Paraliobacillus, 93.7-94.1 % to the genus Gracilibacillus and 93.8-94.2 % to Virgibacillus marismortui. On the basis of possession of physiological and biochemical characteristics common to typical lactic acid

  20. Using natural biomass microorganisms for drinking water denitrification.

    Science.gov (United States)

    Costa, Darleila Damasceno; Gomes, Anderson Albino; Fernandes, Mylena; Lopes da Costa Bortoluzzi, Roseli; Magalhães, Maria de Lourdes Borba; Skoronski, Everton

    2018-07-01

    Among the methods that are studied to eliminate nitrate from drinking water, biological denitrification is an attractive strategy. Although several studies report the use of denitrifying bacteria for nitrate removal, they usually involve the use of sewage sludge as biomass to obtain the microbiota. In the present study, denitrifying bacteria was isolated from bamboo, and variable parameters were controlled focusing on optimal bacterial performance followed by physicochemical analysis of water adequacy. In this way, bamboo was used as a source of denitrifying microorganisms, using either Immobilized Microorganisms (IM) or Suspended Microorganisms (SM) for nitrate removal. Denitrification parameters optimization was carried out by analysis of denitrification at different pH values, temperature, nitrate concentrations, carbon sources as well as different C/N ratios. In addition, operational stability and denitrification kinetics were evaluated. Microorganisms present in the biomass responsible for denitrification were identified as Proteus mirabilis. The denitrified water was submitted to physicochemical treatment such as coagulation and flocculation to adjust to the parameters of color and turbidity to drinking water standards. Denitrification using IM occurred with 73% efficiency in the absence of an external carbon source. The use of SM provided superior denitrification efficiency using ethanol (96.46%), glucose (98.58%) or glycerol (98.5%) as carbon source. The evaluation of the operational stability allowed 12 cycles of biomass reuse using the IM and 9 cycles using the SM. After physical-chemical treatment, only SM denitrified water remained within drinking water standards parameters of color and turbidity. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. Oligotrophic bacteria isolated from clinical materials.

    OpenAIRE

    Tada, Y; Ihmori, M; Yamaguchi, J

    1995-01-01

    Oligotrophic bacteria (oligotrophs) are microorganisms that grow in extremely nutritionally deficient conditions in which the concentrations of organic substances are low. Many oligotrophic bacteria were isolated from clinical materials including urine, sputum, swabbings of the throat, vaginal discharges, and others. Seventy-seven strains of oligotrophic bacteria from 871 samples of clinical material were isolated. A relatively higher frequency of isolation of oligotrophic bacteria was shown ...

  2. Draft genome sequence of Vitellibacter aquimaris D-24T isolated from seawater

    Directory of Open Access Journals (Sweden)

    Suganthi Thevarajoo

    Full Text Available ABSTRACT Vitellibacter aquimaris D-24T (=KCTC 42708T = DSM 101732T, a halophilic marine bacterium, was isolated from seawater collected from Desaru beach, Malaysia. Here, we present the draft genome sequence of D-24T with a genome size of approximately 3.1 Mbp and G + C content of 39.93%. The genome of D-24T contains genes involved in reducing a potent greenhouse gas (N2O in the environment and the degradation of proteinaceous compounds. Genome availability will provide insights into potential biotechnological and environmental applications of this bacterium.

  3. Effect of helium-neon laser radiation on conventionally - pathogenous microorganisms

    International Nuclear Information System (INIS)

    Shesterina, M.V.; Kalyuk, A.N.; Maliev, B.M.

    1987-01-01

    Results are reported of single and multiple irradiation with low-energy helium-neon lasers (different doses and regimens) on growth and properties of conventionally-pathogenous microflora isolated from patients with pulmonary tuberculosis and cultures of standard microorganisms. The above mentioned laser radiation produced an inhibitory effect on some strains of conventionally-pathogenous microflora manifested in inhibition of the growth properties of cultures as the energy dose increased

  4. Study on the resistance of haloferax radiotolerans, an extreme Halophilic archaebacterium from Uromia lake against ultraviolet (UV) light and 60Co gamma-rays

    International Nuclear Information System (INIS)

    Asgarni, E.; Shirzad, M.; Soudi, M. R.; Shahmohammadi, H. R.; Falsafi, T.

    2006-01-01

    In this work, the capacity of an extreme halophilic archaebacterium, isolated from Uromia lake, Haloferax radiotolerans to withstand the lethal effects of ultraviolet light (UV),and 60 Co r-rays has been studied. The resistibility of this organism against the DNA-damaging agents was evaluated by calculating of the survival fractions at different dose rates of W and 60 Co r-rays radiations and compared with those of Escherichia coli B/r (a radioresistant strain of E. coli). D 37 values for Haloferax radiotolerans and E. coli B/r were 23 1, and 9 J/m 2 , respectively, by exposure to the UV light. They were 645, and 99 Gy, respectively, by exposure to 60 Co r-rays. Against these agents, Haloferax radiotolerans shows much more resistance compare to that of E. coli B/r. This is categorized as the first report of resistibility in the member of Archaea

  5. Specific single-cell isolation and genomic amplification of uncultured microorganisms

    DEFF Research Database (Denmark)

    Kvist, Thomas; Ahring, Birgitte Kiær; Lasken, R.S.

    2007-01-01

    We in this study describe a new method for genomic studies of individual uncultured prokaryotic organisms, which was used for the isolation and partial genome sequencing of a soil archaeon. The diversity of Archaea in a soil sample was mapped by generating a clone library using group-specific pri......We in this study describe a new method for genomic studies of individual uncultured prokaryotic organisms, which was used for the isolation and partial genome sequencing of a soil archaeon. The diversity of Archaea in a soil sample was mapped by generating a clone library using group......-specific primers in combination with a terminal restriction fragment length polymorphism profile. Intact cells were extracted from the environmental sample, and fluorescent in situ hybridization probing with Cy3-labeled probes designed from the clone library was subsequently used to detect the organisms...... of interest. Single cells with a bright fluorescent signal were isolated using a micromanipulator and the genome of the single isolated cells served as a template for multiple displacement amplification (MDA) using the Phi29 DNA polymerase. The generated MDA product was afterwards used for 16S rRNA gene...

  6. New Cyclic Lipopeptides of the Iturin Class Produced by Saltern-Derived Bacillus sp. KCB14S006

    Directory of Open Access Journals (Sweden)

    Sangkeun Son

    2016-04-01

    Full Text Available Salterns, one of the most extreme natural hypersaline environments, are a rich source of halophilic and halotolerant microorganisms, but they remain largely underexplored ecological niches in the discovery of bioactive secondary metabolites. In continued efforts to investigate the metabolic potential of microbial populations from chemically underexplored sites, three new lipopeptides named iturin F1, iturin F2 and iturin A9 (1–3, along with iturin A8 (4, were isolated from Bacillus sp. KCB14S006 derived from a saltern. The structures of the isolated compounds were established by 1D-, 2D-NMR and HR-ESIMS, and their absolute configurations were determined by applying advanced Marfey’s method and CD spectroscopy. All isolates exhibited significant antifungal activities against various pathogenic fungi and moderate cytotoxic activities toward HeLa and srcts-NRK cell lines. Moreover, in an in vitro enzymatic assay, compound 4 showed a significant inhibitory activity against indoleamine 2,3-dioxygenase.

  7. Investigating the Effects of Simulated Space conditions on Novel Extremely Halophilic Archaea: Halovarius Luteus gen. nov., sp. nov.

    Science.gov (United States)

    Feshangsaz, Niloofar; Van Loon, ing.. Jack J. W. A.; Nazmi, Kamran; Semsarha, Farid

    2016-07-01

    Studying halophiles from different environments of Earth provide new insights into our search for life in the universe. Haloarchaea show some unique characteristics and physiological adaptations like acidic proteins against harsh environments such as natural brine with salt concentration approaching saturation (5 M) and regions with low active water. These properties make haloarchaea interesting candidate for astrobiological studies. Halovarius luteus gen. nov., sp. nov. a novel extremely halophilic archaeon from Urmia salt lake, in Iran has been chosen to explore its resistance against a series of extreme conditions. The aim of this study is to assess the resistance of strain DA50T under the effects of simulated space conditions like simulated microgravity, hypergravity, and desiccation. In this paper we will discuss the results of these studies where we specifically focus on changes in carotenoid pigments production and whole cell proteome. This is the first report of very novel Iranian archaea in response to extreme space conditions. The pigments were extracted by acetone and methanol. Pigments were analyzed by scanning the absorbance spectrum in the UV-VIS spectrophotometer. And they were separated by TLC. Whole protein from cell lysate supernatant was extracted after lysis with Bacterial Protein Extraction Reagent and fractionated by RP-HPLC using C18 column. Proteome analyzed by electrophoresis (SDS-PAGE), and MALDI-TOF. Carotenoid pigments are formed under different extreme conditions such as dry environment and gravitational changes. Also the protein composition exhibits alterations after exposure to the same conditions. Our conclusion is that pigments and proteins formation depend on the growth circumstances. Halophiles use this as an adaptation to survive under different environmental conditions.

  8. Fossil micro-organisms evidenced by electronic microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Prashnowsky, A.A.; Oberlies, F.; Burger, K.

    1983-04-01

    Fossil microorganisms in colonies and in the form of isolated cells (iron bacteria, fungi, actinomycetes etc.) were detected by electron microscopy of rocks containing remains of plant roots, carbonaceous substance, and strata of clay iron stone with ooids. These findings suggest an environment favourable to bacterial activity during sedimentation in the Upper Carboniferous and during the later processes of peat and coal formation. They also suggest that bacterial processes are an important factor in coal formation. Accurate data on coal formation can only be obtained by systematic biochemical studies. Analyses of the defined organic substances provide a better understanding of the conversion processes of the original substances. For example, the results of sterine analysis provide information on the mycoplancton, phytoplancton and zooplancton of the Upper Carboniferous. For some types of rock, the ratio of saponifiable to non-saponifiable constituents of the organic compounds yield information on stability under various geochemical conditions. The interactions between the various groups of microorganisms also play a major role in the solution of ecological problems.

  9. Effects of microbial processes on gas generation under expected WIPP repository conditions: Annual report through 1992

    International Nuclear Information System (INIS)

    Francis, A.J.; Gillow, J.B.

    1993-09-01

    Microbial processes involved in gas generation from degradation of the organic constituents of transuranic waste under conditions expected at the Waste Isolation Pilot Plant (WIPP) repository are being investigated at Brookhaven National Laboratory. These laboratory studies are part of the Sandia National Laboratories -- WIPP Gas Generation Program. Gas generation due to microbial degradation of representative cellulosic waste was investigated in short-term ( 6 months) experiments by incubating representative paper (filter paper, paper towels, and tissue) in WIPP brine under initially aerobic (air) and anaerobic (nitrogen) conditions. Samples from the WIPP surficial environment and underground workings harbor gas-producing halophilic microorganisms, the activities of which were studied in short-term experiments. The microorganisms metabolized a variety of organic compounds including cellulose under aerobic, anaerobic, and denitrifying conditions. In long-term experiments, the effects of added nutrients (trace amounts of ammonium nitrate, phosphate, and yeast extract), no nutrients, and nutrients plus excess nitrate on gas production from cellulose degradation

  10. Spiribacter roseus sp. nov., a moderately halophilic species of the genus Spiribacter from salterns.

    Science.gov (United States)

    León, María José; Vera-Gargallo, Blanca; Sánchez-Porro, Cristina; Ventosa, Antonio

    2016-10-01

    Four pink-pigmented, non-motile, Gram-staining-negative and moderately halophilic curved rods, designated strains SSL50T, SSL25, SSL97 and SSL4, were isolated from a saltern located in Isla Cristina, Huelva, south-west Spain. Phylogenetic analyses based on 16S rRNA gene sequences showed that they were members of the genus Spiribacter, most closely related to Spiribacter curvatus UAH-SP71T (99.3-99.5 % sequence similarity) and Spiribacter salinus M19-40T (96.5-96.7 %). Other related strains were Alkalilimnicola ehrlichii MLHE-1T (95.1-95.3 %), Arhodomonas recens RS91T (95.1-95.2 %) and Arhodomonas aquaeolei ATCC 49307T (95.0-95.1 %), all members of the family Ectothiorhodospiraceae. The major fatty acids were C18 : 1ω6c and/or C18 : 1ω7c, C16 : 0 and C12 : 0. The DNA G+C range was 64.0-66.3 mol%. The DNA-DNA hybridization values between strains SSL50T, SSL25, SSL97, SSL4 and S. piribacter. curvatus UAH-SP71T were 37-49 %. The average nucleotide identity (ANIb) values between the genome of strain SSL50T and those of the two other representatives of the genus Spiribacter, S. curvatus UAH-SP71T and S. salinus M19-40T, were 82.4 % and 79.1 %, respectively, supporting the proposal of a novel species of the genus Spiribacter. On the basis of the polyphasic analysis, the four new isolates are considered to represent a novel species of the genus Spiribacter, for which the name Spiribacter roseus sp. nov. is proposed. The type strain is SSL50T (=CECT 9117T=IBRC-M 11076T).

  11. α-Amylase production by Penicillium fellutanum isolated from ...

    African Journals Online (AJOL)

    GRACE

    2006-05-16

    May 16, 2006 ... products obtained by starch hydrolysis. Since this natural isolate produced low concentration of amylase, attempts were made to increase the productivity by optimizing the cultural conditions. MATERIALS AND METHODS. Microorganism. The fungus, Penicillium fellutanum Biourge., was isolated from.

  12. Complete genome sequence of Vibrio anguillarum strain NB10, a virulent isolate from the Gulf of Bothnia.

    Science.gov (United States)

    Holm, Kåre Olav; Nilsson, Kristina; Hjerde, Erik; Willassen, Nils-Peder; Milton, Debra L

    2015-01-01

    Vibrio anguillarum causes a fatal hemorrhagic septicemia in marine fish that leads to great economical losses in aquaculture world-wide. Vibrio anguillarum strain NB10 serotype O1 is a Gram-negative, motile, curved rod-shaped bacterium, isolated from a diseased fish on the Swedish coast of the Gulf of Bothnia, and is slightly halophilic. Strain NB10 is a virulent isolate that readily colonizes fish skin and intestinal tissues. Here, the features of this bacterium are described and the annotation and analysis of its complete genome sequence is presented. The genome is 4,373,835 bp in size, consists of two circular chromosomes and one plasmid, and contains 3,783 protein-coding genes and 129 RNA genes.

  13. Isolation and enzyme bioprospection of endophytic bacteria associated with plants of Brazilian mangrove ecosystem.

    Science.gov (United States)

    Castro, Renata A; Quecine, Maria Carolina; Lacava, Paulo T; Batista, Bruna D; Luvizotto, Danice M; Marcon, Joelma; Ferreira, Anderson; Melo, Itamar S; Azevedo, João L

    2014-01-01

    The mangrove ecosystem is a coastal tropical biome located in the transition zone between land and sea that is characterized by periodic flooding, which confers unique and specific environmental conditions on this biome. In these ecosystems, the vegetation is dominated by a particular group of plant species that provide a unique environment harboring diverse groups of microorganisms, including the endophytic microorganisms that are the focus of this study. Because of their intimate association with plants, endophytic microorganisms could be explored for biotechnologically significant products, such as enzymes, proteins, antibiotics and others. Here, we isolated endophytic microorganisms from two mangrove species, Rhizophora mangle and Avicennia nitida, that are found in streams in two mangrove systems in Bertioga and Cananéia, Brazil. Bacillus was the most frequently isolated genus, comprising 42% of the species isolated from Cananéia and 28% of the species from Bertioga. However, other common endophytic genera such as Pantoea, Curtobacterium and Enterobacter were also found. After identifying the isolates, the bacterial communities were evaluated for enzyme production. Protease activity was observed in 75% of the isolates, while endoglucanase activity occurred in 62% of the isolates. Bacillus showed the highest activity rates for amylase and esterase and endoglucanase. To our knowledge, this is the first reported diversity analysis performed on endophytic bacteria obtained from the branches of mangrove trees and the first overview of the specific enzymes produced by different bacterial genera. This work contributes to our knowledge of the microorganisms and enzymes present in mangrove ecosystems.

  14. Biochemical characterization of a halophilic, alkalithermophilic protease from Alkalibacillus sp. NM-Da2.

    Science.gov (United States)

    Abdel-Hamed, Asmaa R; Abo-Elmatty, Dina M; Wiegel, Juergen; Mesbah, Noha M

    2016-11-01

    An extracellular, halophilic, alkalithermophilic serine protease from the halo-alkaliphilic Alkalibacillus sp. NM-Da2 was purified to homogeneity by ethanol precipitation and anion-exchange chromatography. The purified protease was a monomeric enzyme with an approximate molecular mass of 35 kDa and exhibited maximal activity at 2.7 M NaCl, pH 55 °C 9 and 56 °C. The protease showed great temperature stability, retaining greater than 80 % of initial activity after 2 h incubation at 55 °C. The protease was also extremely pH tolerant, retaining 80 % of initial activity at pH 55 °C 10.5 after 30 min incubation. Protease hydrolyzed complex substrates, displaying activity on yeast extract, tryptone, casein, gelatin and peptone. Protease activity was inhibited at casein concentrations greater than 1.2 mg/mL. The enzyme was stable and active in 40 % (v/v) solutions of isopropanol, ethanol and benzene and was stable in the presence of the polysorbate surfactant Tween 80. Activity was stimulated with the oxidizing agent hydrogen peroxide. Inhibition with phenyl methylsulfonylfluoride indicates it is a serine protease. Synthetic saline wastewater treated with the protease showed 50 % protein removal after 5 h. Being halophilic, alkaliphilic and thermophilic, in addition to being resistant to organic solvents, this protease has potential for various applications in biotechnological and pharmaceutical industries.

  15. Novel Insights into the Diversity of Catabolic Metabolism from Ten Haloarchaeal Genomes

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, Iain; Scheuner, Carmen; Goker, Markus; Mavromatis, Kostas; Hooper, Sean D.; Porat, Iris; Klenk, Hans-Peter; Ivanova, Natalia; Kyrpides, Nikos

    2011-05-03

    The extremely halophilic archaea are present worldwide in saline environments and have important biotechnological applications. Ten complete genomes of haloarchaea are now available, providing an opportunity for comparative analysis. We report here the comparative analysis of five newly sequenced haloarchaeal genomes with five previously published ones. Whole genome trees based on protein sequences provide strong support for deep relationships between the ten organisms. Using a soft clustering approach, we identified 887 protein clusters present in all halophiles. Of these core clusters, 112 are not found in any other archaea and therefore constitute the haloarchaeal signature. Four of the halophiles were isolated from water, and four were isolated from soil or sediment. Although there are few habitat-specific clusters, the soil/sediment halophiles tend to have greater capacity for polysaccharide degradation, siderophore synthesis, and cell wall modification. Halorhabdus utahensis and Haloterrigena turkmenica encode over forty glycosyl hydrolases each, and may be capable of breaking down naturally occurring complex carbohydrates. H. utahensis is specialized for growth on carbohydrates and has few amino acid degradation pathways. It uses the non-oxidative pentose phosphate pathway instead of the oxidative pathway, giving it more flexibility in the metabolism of pentoses. These new genomes expand our understanding of haloarchaeal catabolic pathways, providing a basis for further experimental analysis, especially with regard to carbohydrate metabolism. Halophilic glycosyl hydrolases for use in biofuel production are more likely to be found in halophiles isolated from soil or sediment.

  16. Isolation and characterization of acetate-utilizing anaerobes from a freshwater sediment

    NARCIS (Netherlands)

    Scholten, J.C.M.; Stams, A.J.M.

    2000-01-01

    Acetate-degrading anaerobic microorganisms in freshwater sediment were quantified by the most probable number technique. From the highest dilutions a methanogenic, a sulfate-reducing, and a nitrate-reducing microorganism were isolated with acetate as substrate. The methanogen (culture AMPB-Zg) was

  17. Periodontopathic microorganisms in peripheric blood after scaling and root planing.

    Science.gov (United States)

    Lafaurie, Gloria Inés; Mayorga-Fayad, Isabel; Torres, María Fernanda; Castillo, Diana Marcela; Aya, Maria Rosario; Barón, Alexandra; Hurtado, Paola Andrea

    2007-10-01

    The objective of this study was to evaluate the frequency of periodontopathic and other subgingival anaerobic and facultative bacteria in the bloodstream following scaling and root planing (SRP). Forty-two patients with severe generalized chronic periodontitis (GChP) and generalized aggressive periodontitis (GAgP) were included in the study. Four samples of peripheric blood were drawn from the cubital vein at different times: Pre-treatment: immediately before the SRP procedure (T1), immediately after treatment (T2), 15 min. post-treatment (T3) and 30 min. post-treatment (T4). In order to identify the presence of microorganisms in blood, subcultures were conducted under anaerobic conditions. 80.9% of the patients presented positive cultures after SRP and it occurred more frequently immediately after treatment; however, 19% of the patients still had microorganisms in the bloodstream 30 min. after the procedure. The periodontopathic microorganisms more frequently identified were Porphyromonas gingivalis and Micromonas micros. Campylobacter spp., Eikenella corrodens, Tannerella forsythensis, Fusobacterium spp. and Prevotella intermedia were isolated less often. Actinomyces spp. were also found frequently during bacteraemia after SRP. SRP induced bacteraemia associated with anaerobic bacteria, especially in patients with periodontal disease.

  18. Reconstruction of the High-Osmolarity Glycerol (HOG) Signaling Pathway from the Halophilic Fungus Wallemia ichthyophaga in Saccharomyces cerevisiae.

    Science.gov (United States)

    Konte, Tilen; Terpitz, Ulrich; Plemenitaš, Ana

    2016-01-01

    The basidiomycetous fungus Wallemia ichthyophaga grows between 1.7 and 5.1 M NaCl and is the most halophilic eukaryote described to date. Like other fungi, W. ichthyophaga detects changes in environmental salinity mainly by the evolutionarily conserved high-osmolarity glycerol (HOG) signaling pathway. In Saccharomyces cerevisiae, the HOG pathway has been extensively studied in connection to osmotic regulation, with a valuable knock-out strain collection established. In the present study, we reconstructed the architecture of the HOG pathway of W. ichthyophaga in suitable S. cerevisiae knock-out strains, through heterologous expression of the W. ichthyophaga HOG pathway proteins. Compared to S. cerevisiae, where the Pbs2 (ScPbs2) kinase of the HOG pathway is activated via the SHO1 and SLN1 branches, the interactions between the W. ichthyophaga Pbs2 (WiPbs2) kinase and the W. ichthyophaga SHO1 branch orthologs are not conserved: as well as evidence of poor interactions between the WiSho1 Src-homology 3 (SH3) domain and the WiPbs2 proline-rich motif, the absence of a considerable part of the osmosensing apparatus in the genome of W. ichthyophaga suggests that the SHO1 branch components are not involved in HOG signaling in this halophilic fungus. In contrast, the conserved activation of WiPbs2 by the S. cerevisiae ScSsk2/ScSsk22 kinase and the sensitivity of W. ichthyophaga cells to fludioxonil, emphasize the significance of two-component (SLN1-like) signaling via Group III histidine kinase. Combined with protein modeling data, our study reveals conserved and non-conserved protein interactions in the HOG signaling pathway of W. ichthyophaga and therefore significantly improves the knowledge of hyperosmotic signal processing in this halophilic fungus.

  19. Aspergillus atacamensis and A. salisburgensis: two new halophilic species from hypersaline/arid habitats with a phialosimplex-like morphology.

    Science.gov (United States)

    Martinelli, Livia; Zalar, Polona; Gunde-Cimerman, Nina; Azua-Bustos, Armando; Sterflinger, Katja; Piñar, Guadalupe

    2017-07-01

    Halophilic fungal strains isolated from historical wooden staircase in a salt mine in Austria, and from wall biofilm and soil of a cave in the Coastal Range of the hyperarid Atacama Desert in Chile were characterised and described newly as Aspergillus salisburgensis and Aspergillus atacamensis. Morphological characters including solitary phialides producing solitary conidia and conidia in chains and/or heads suggested affinity to Aspergillus subgenus Polypaecilum. Strains required salt for growth, grew optimally on media with 10-25% NaCl and at 15-28 °C. These values are similar to those observed for Aspergillus salinarus comb. nov. (Phialosimplex salinarum), while the ex-type strains of Aspergillus sclerotialis, Aspergillus chlamydosporus and Aspergillus caninus (all belonging to Aspergillus subgen. Polypaecilum) grew optimally at 0-5% NaCl and showed fastest growth at 28-37 °C. Phylogenetic analyses on the basis of rDNA sequences, RAPD-PCR fingerprint patterns, and cellobiohydrolase gene (cbh-I) polymorphism clustered the strains into three groups and supported their taxonomic recognition as A. salinarus, A. atacamensis and A. salisburgensis. On the basis of phylogenetic inferences, also Sagenomella keratitidis is newly combined as Aspergillus keratitidis and inferred as a species of Aspergillus subgenus Polypaecilum.

  20. Thermal effects on metabolic activities of thermophilic microorganisms from the thermal discharge point of Tuticorin thermal power plant area

    International Nuclear Information System (INIS)

    Muthukkannan, N.; Murugesan, A.G.

    2002-01-01

    Metabolic activities of thermophilic microorganisms isolated from the thermal water discharge point at Tuticorin thermal power station were studied by growing the microorganisms in sterile medium and at various temperature regimes of 25, 35, 45, 55 and 65degC. The optimum temperature for the growth of the bacterium isolated from the thermal power plant station was 45 degC and beyond 65 degC the growth was gradually decreased. The bacteria isolated from open sea water were mesophiles with their growth optimum at 35 degC and microbes inhabiting the thermal discharge area were thermopiles as they were tolerant even at 55 degC. The amylase production, carbohydrate metabolism and lactose fermentation activities were optimum at 45 degC. At 25 degC and beyond 65 degC biochemical activities of the organisms were inhibited to a greater extent. (author)

  1. Chloride Activated Halophilic α-Amylase from Marinobacter sp. EMB8: Production Optimization and Nanoimmobilization for Efficient Starch Hydrolysis

    Directory of Open Access Journals (Sweden)

    Sumit Kumar

    2015-01-01

    Full Text Available Halophiles have been perceived as potential source of novel enzymes in recent years. The interest emanates from their ability to catalyze efficiently under high salt and organic solvents. Present work encompasses production optimization and nanoimmobilization of an α-amylase from moderately halophilic Marinobacter sp. EMB8. Media ingredients and culture conditions were optimized by “one-at-a-time approach.” Starch was found to be the best carbon source at 5% (w/v concentration. Glucose acted as catabolic repressor for amylase production. Salt proved critical for amylase production and maximum production was attained at 5% (w/v NaCl. Optimization of various culture parameters resulted in 48.0 IU/mL amylase production, a 12-fold increase over that of unoptimized condition (4.0 IU/mL. α-Amylase was immobilized on 3-aminopropyl functionalized silica nanoparticles using glutaraldehyde as cross-linking agent. Optimization of various parameters resulted in 96% immobilization efficiency. Starch hydrolyzing efficiency of immobilized enzyme was comparatively better. Immobilized α-amylase retained 75% of its activity after 5th cycle of repeated use.

  2. Degradation of 2,4-D herbicide by microorganisms isolated from Brazilian contaminated soil Degradação do herbicida 2,4-D por microrganismos isolados de solo contaminado do Brasil

    Directory of Open Access Journals (Sweden)

    Tatiane M. Silva

    2007-09-01

    Full Text Available The aim of this work was to isolate microorganisms from Brazilian soil contaminated with 2,4-D herbicide, and analyze the efficiency for 2,4D degradation, using high-performance liquid chromatography (HPLC. Serratia marcescens and Penicillium sp had never been reported as able to degrade 2,4-D. The isolated strains represent a great potential for bioremediation.O objetivo deste trabalho foi isolar microrganismos de solo brasileiro contaminado com o herbicida 2,4-D, e analisar a eficiência da degradação por cromatografia líquida de alta eficiência (HPLC. Serratia marcescens e Penicillium sp jamais haviam sido relatadas como degradadoras de 2,4-D. As linhagens isoladas representam um grande potencial em biorremediação.

  3. Bacterial community analysis of an industrial wastewater treatment plant in Colombia with screening for lipid-degrading microorganisms.

    Science.gov (United States)

    Silva-Bedoya, Lina Marcela; Sánchez-Pinzón, María Solange; Cadavid-Restrepo, Gloria Ester; Moreno-Herrera, Claudia Ximena

    2016-11-01

    The operation of wastewater treatment technologies depends on a combination of physical, chemical and biological factors. Microorganisms present in wastewater treatment plants play essential roles in the degradation and removal of organic waste and xenobiotic pollutants. Several microorganisms have been used in complementary treatments to process effluents rich in fats and oils. Microbial lipases have received significant industrial attention because of their stability, broad substrate specificity, high yields, and regular supply, as well as the fact that the microorganisms producing them grow rapidly on inexpensive media. In Colombia, bacterial community studies have focused on populations of cultivable nitrifying, heterotrophic and nitrogen-fixing bacteria present in constructed wetlands. In this study, culture-dependent methods, culture-independent methods (TTGE, RISA) and enzymatic methods were used to estimate bacterial diversity, to monitor temporal and spatial changes in bacterial communities, and to screen microorganisms that presented lipolytic activity. The dominant microorganisms in the Wastewater Treatment Plant (WWTP) examined in this study belonged to the phyla Firmicutes, Proteobacteria and Bacteroidetes. The enzymatic studies performed indicated that five bacterial isolates and three fungal isolates possessed the ability to degrade lipids; additionally, the Serratia, Kosakonia and Mucor genera presented lipase-mediated transesterification activity. The implications of these findings in regard to possible applications are discussed later in this paper. Our results indicate that there is a wide diversity of aerobic Gram-negative bacteria inhabiting the different sections of the WWTP, which could indicate its ecological condition, functioning and general efficiency. Copyright © 2016 Elsevier GmbH. All rights reserved.

  4. Thermophilic microorganisms in biomining.

    Science.gov (United States)

    Donati, Edgardo Rubén; Castro, Camila; Urbieta, María Sofía

    2016-11-01

    Biomining is an applied biotechnology for mineral processing and metal extraction from ores and concentrates. This alternative technology for recovering metals involves the hydrometallurgical processes known as bioleaching and biooxidation where the metal is directly solubilized or released from the matrix for further solubilization, respectively. Several commercial applications of biomining can be found around the world to recover mainly copper and gold but also other metals; most of them are operating at temperatures below 40-50 °C using mesophilic and moderate thermophilic microorganisms. Although biomining offers an economically viable and cleaner option, its share of the world´s production of metals has not grown as much as it was expected, mainly considering that due to environmental restrictions in many countries smelting and roasting technologies are being eliminated. The slow rate of biomining processes is for sure the main reason of their poor implementation. In this scenario the use of thermophiles could be advantageous because higher operational temperature would increase the rate of the process and in addition it would eliminate the energy input for cooling the system (bioleaching reactions are exothermic causing a serious temperature increase in bioreactors and inside heaps that adversely affects most of the mesophilic microorganisms) and it would decrease the passivation of mineral surfaces. In the last few years many thermophilic bacteria and archaea have been isolated, characterized, and even used for extracting metals. This paper reviews the current status of biomining using thermophiles, describes the main characteristics of thermophilic biominers and discusses the future for this biotechnology.

  5. Ventilator-Associated Pneumonia and Causative Microorganisms in Intensive Care Unit: A Two Year Retrospective Analysis

    Directory of Open Access Journals (Sweden)

    Onur Palabıyık

    2016-12-01

    Full Text Available Objective: Ventilator-associated pneumonia (VAP is the most common nosocomial infection in the intensive care units (ICUs. It causes prolonged hospital stay and increases mortality. In this study, we aimed to investigate the rate of VAP, causative microorganisms, and their antibiotic susceptibilities in anaesthesiology and reanimation ICU (ARICU. Material and Method: This retrospective study included patients who were admitted to 12-bed ARICU between January 2013 and December 2014. The detection of VAP was done according to Centers for Disease Control and Prevention criteria. The rate of VAP, VAP ratio, and ventilator utilization ratio (VUR were calculated according to guidelines of Turkish National Infection Surveillance Control Group. Endotracheal aspiration samples were collected and cultivated. The identification of the isolates was performed by using VITEK-2 automated system. Antibiotic susceptibilities were determined by the disc diffusion method according to the Clinical and Laboratory Standards Institute criteria. Results: VAP was determined in 16 of 359 patients who required invasive mechanic ventilation for longer than 48 hours and hospitalized in ARICU. VUR was 65%, VAP ratio was 4.5% and the rate of VAP was 3.3 per 1000 ventilator days. Seventeen microorganisms were isolated from endotracheal aspiration samples, including Acinetobacter baumannii (n=6, Pseudomonas aeruginosa (n=4, methicillin-resistant Staphylococcus aureus (n=4, Klebsiella pneumoniae, Enterobacter cloacae and Serratia marcescens. The most sensitive antibiotics for microorganisms are listed as follows; Acinetobacter baumannii: colistin, Pseudomonas aeruginosa: amikacin, carbapenems; Methicillin-resistant Staphylococcus aureus: linezolid, teicoplanin, vancomycin, trimethoprim sulfamethoxazole; Klebsiella and Enterobacteriaceae species: carbapenems, trimethoprim sulfamethoxazole, gentamicin. Conclusion: Intermittent analyses and antibiotic susceptibilities of VAP

  6. Salinivibrio costicola GL6, a Novel Isolated Strain for Biotransformation of Caffeine to Theobromine Under Hypersaline Conditions.

    Science.gov (United States)

    Ashengroph, Morahem

    2017-01-01

    The present study has been conducted towards isolation of moderately halophilic bacteria capable of transforming caffeine into theobromine. A total of 45 caffeine-degrading moderate halophiles were enriched from hypersaline lakes and examined for the biotransformation of caffeine to theobromine by thin-layer chromatography (TLC) and high-performance liquid chromatography analyses. Strain GL6, giving the highest yield of theobromine, was isolated from the Hoz Soltan Lake, 20 % w/v salinity, central Iran, and identified as Salinivibrio costicola based on morphological and biochemical features as well as its 16S rRNA gene sequence analysis (GeneBank Accession No. KT378066) and DNA-DNA relatedness. The biotransformation of caffeine with strain GL6 leads to the formation of two metabolites, identified as theobromine and paraxanthine, but the yield of paraxanthine was much lower. Further study on the production of theobromine from caffeine under resting cell experiment was carried out subsequently. The optimal yield of theobromine (56 %) was obtained after a 32-h incubation using 5 mM of caffeine and 15 g l -1 (wet weight) of biomass in 0.1 M saline phosphate buffer (pH 7.0 and 10 % w/v NaCl) under agitation 180 rpm at 30 °C. The biotransformed theobromine was purified by preparative TLC and subjected to FTIR and mass spectroscopy for chemical identification. This is the first evidence for biotransformation of caffeine into theobromine by strains of the genus Salinivibrio.

  7. No evidential correlation between veterinary antibiotic degradation ability and resistance genes in microorganisms during the biodegradation of doxycycline.

    Science.gov (United States)

    Wen, Xin; Wang, Yan; Zou, Yongde; Ma, Baohua; Wu, Yinbao

    2018-01-01

    Biodegradation of antibiotic residues in the environment by microorganisms may lead to the generation of antibiotic resistance genes (ARGs), which are of great concern to human health. The aim of this study was to determine whether there is a relationship between the ability to degrade antibiotic doxycycline (DOX) and the development of resistance genes in microorganisms. We isolated and identified ten bacterial strains from a vegetable field that had received long-term manure application as fertilizer and were capable of surviving in a series of DOX concentrations (25, 50, 80, and 100mg/L). Our results showed no evidential correlation between DOX degradation ability and the development of resistance genes among the isolated microorganisms that had high DOX degradation capability (P > 0.05). This was based on the fact that Escherichia sp. and Candida sp. were the most efficient bacterial strains to degrade DOX (92.52% and 91.63%, respectively), but their tetracycline resistance genes showed a relatively low risk of antibiotic resistance in a 7-day experiment. Moreover, the tetM of the ribosomal protection protein genes carried by these two preponderant bacteria was five-fold higher than that carried by other isolates (P genes of three isolates, except for Escherichia sp. and Candida sp., showed remarkable negative correlations (P < 0.05), mainly because tetG markedly increased during the DOX degradation process. Our results concluded that the biodegradation of antibiotic residues may not necessarily lead to the development of ARGs in the environment. In addition, the two bacteria that we isolated, namely, Escherichia sp. and Candida sp., are potential candidates for the engineering of environmentally friendly bacteria. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Isolation and characterization of new facultative alkaliphilic Bacillus flexus strains from maize processing waste water (nejayote).

    Science.gov (United States)

    Sanchez-Gonzalez, M; Blanco-Gamez, A; Escalante, A; Valladares, A G; Olvera, C; Parra, R

    2011-04-01

    This work describes the isolation and characterization of two new alkaliphilic micro-organisms present in nejayote. Samples of fresh industrial nejayote were plated on nejayote medium and incubated for 4 days at 37 °C. Isolates were identified based on morphological and physiological characteristics, as well as 16S rDNA sequence analysis. Two gram-positive strains, NJY2 and NJY4, able to hydrolyse starch, xylan, and gelatin were isolated from nejayote. Comparative sequence analysis of 16S rDNA and phylogenetic studies indicate that the micro-organisms studied were closely related to members of the Bacillus flexus species. The strains were identified as facultative alkaliphilic salt tolerant bacteria. Isolate NJY2 produced cell associated phenolic acid esterases, able to release ferulic acid from nixtamalised corn bran and ethyl and methyl esters. The isolated strains of B. flexus NJY2 and NJY4 showed important physiological properties to produce high-value molecules from agroindustrial by-products. This is the first report about the isolation of alkaliphilic micro-organisms from nejayote and the first report of phenolic acid esterases synthesised by alkaliphiles. The new alkaliphilic micro-organisms have potential application in the treatment and transformation of tortilla industry residues. © 2011 The Authors. Letters in Applied Microbiology © 2011 The Society for Applied Microbiology.

  9. Antimicrobial blue light inactivation of biofilms formed by clinical isolates of multidrug-resistant microorganisms

    Science.gov (United States)

    Ferrer-Espada, Raquel; Fang, Yanyan; Dai, Tianhong

    2018-02-01

    Antibiotic resistance is one of the most serious threats to public health. It is estimated that at least 23,000 people die each year in the USA as a direct result of antibiotic-resistant infections. In addition, many antibiotic-resistant microorganisms develop biofilms, surface-associated microbial communities that are extremely resistant to antibiotics and the immune system. A light-based approach, antimicrobial blue light (aBL), has attracted increasing attention due to its intrinsic antimicrobial effect without the involvement of exogenous photosensitizers. In this study, we investigated the effectiveness of this non-antibiotic approach against biofilms formed by multidrug-resistant (MDR) microorganisms. MDR Acinetobacter baumannii, Escherichia coli, Candida albicans, and Pseudomonas aeruginosa biofilms were grown either in 96-well microtiter plates for 24 h or in a CDC biofilm reactor for 48 h, and then exposed to aBL at 405 nm emitted from a light-emitting diode (LED). We demonstrated that, for the biofilms grown in the CDC biofilm reactor, approximately 1.88 log10 CFU reduction was achieved in A. baumannii, 2.78 log10 CFU in E. coli and 3.18 log10 CFU in P. aeruginosa after 162 J/cm2 , 576 J/cm2 and 500 J/cm2 aBL were delivered, respectively. For the biofilms formed in the 96-well microtiter plates, 5.67 and 2.46 log10 CFU reduction was observed in P. aeruginosa and C. albicans polymicrobial biofilm after an exposure of 216 J/cm2 . In conclusion, aBL is potentially an alternative non-antibiotic approach against MDR biofilm-related infections. Future studies are warranted to investigate other important MDR microorganisms, the mechanism of action of aBL, and aBL efficacy in vivo.

  10. Dregs of our forgotten ancestors: fermentative microorganisms in the prehistory of Europe, the steppes and Indo-Iranian Asia, and their contemporary use in traditional and probiotic beverages

    Science.gov (United States)

    Fermentative microorganisms in the yeast genera Debaryomyces, Hyphopichia, Kluyveromyces, Lachancea, Saccharomyces, and Wickerhamomyces (and in the bacterial genus Lactobacillus) have been isolated from a variety of fermented beverages. These same microorganisms were very likely unknowingly utilized...

  11. Isolation and identification of halotolerant soil bacteria from coastal Patenga area.

    Science.gov (United States)

    Rahman, Shafkat Shamim; Siddique, Romana; Tabassum, Nafisa

    2017-10-30

    Halotolerant bacteria have multiple uses viz. fermentation with lesser sterility control and industrial production of bioplastics. Moreover, it may increase the crop productivity of coastal saline lands in Bangladesh by transferring the salt tolerant genes into the plants. The study focused on the isolation and identification of the halotolerant bacteria from three soil samples, collected from coastal Patenga area. The samples were inoculated in nutrient media containing a wide range of salt concentrations. All the samples showed 2, 4 and 6% (w/v) salt tolerance. The isolates from Patenga soil (4, 6%) and beach soil (2%) showed catalase activity and all the isolates showed negative results for oxidase activity, indole production, lactose and motility. All the samples provided positive results for dextrose fermentation. Other tests provided mixed results. Based on the morphological characteristics, biochemical tests and ABIS software analysis the isolates fall within the Enterobacteriaceae, Clostridium and Corynebacterium, with a predominance of Vibrios. Overall the isolates can be considered as mild halotolerant, with the best growth observed at lower salinities and no halophilism detected. Among many possibilities, the genes responsible for the salt tolerant trait in these species can be identified, extracted and inserted into the crop plants to form a transgenic plant to result in higher yield for the rest of the year.

  12. The effect of high ionic strength on neptunium (V) adsorption to a halophilic bacterium

    Science.gov (United States)

    Ams, David A.; Swanson, Juliet S.; Szymanowski, Jennifer E. S.; Fein, Jeremy B.; Richmann, Michael; Reed, Donald T.

    2013-06-01

    The mobility of neptunium (V) in subsurface high ionic strength aqueous systems may be strongly influenced by adsorption to the cell wall of the halophilic bacteria Chromohalobacter sp. This study is the first to evaluate the adsorption of neptunium (V) to the surface of a halophilic bacterium as a function of pH from approximately 2 to 10 and at ionic strengths of 2 and 4 M. This is also the first study to evaluate the effects of carbonate complexation with neptunium (V) on adsorption to whole bacterial cells under high pH conditions. A thermodynamically-based surface complexation model was adapted to describe experimental adsorption data under high ionic strength conditions where traditional corrections for aqueous ion activity are invalid. Adsorption of neptunium (V) was rapid and reversible under the conditions of the study. Adsorption was significant over the entire pH range evaluated for both ionic strength conditions and was shown to be dependent on the speciation of the sites on the bacterial surface and neptunium (V) in solution. Adsorption behavior was controlled by the relatively strong electrostatic attraction of the positively charged neptunyl ion to the negatively charged bacterial surface at pH below circum-neutral. At pH above circum-neutral, the adsorption behavior was controlled by the presence of negatively charged neptunium (V) carbonate complexes resulting in decreased adsorption, although adsorption was still significant due to the adsorption of negatively charged neptunyl-carbonate species. Adsorption in 4 M NaClO4 was enhanced relative to adsorption in 2 M NaClO4 over the majority of the pH range evaluated, likely due to the effect of increasing aqueous ion activity at high ionic strength. The protonation/deprotonation characteristics of the cell wall of Chromohalobacter sp. were evaluated by potentiometric titrations in 2 and 4 M NaClO4. Bacterial titration results indicated that Chromohalobacter sp. exhibits similar proton buffering

  13. Characterization of detergent compatible protease of a halophilic Bacillus sp. EMB9: differential role of metal ions in stability and activity.

    Science.gov (United States)

    Sinha, Rajeshwari; Khare, S K

    2013-10-01

    A moderately halophilic protease producer, Bacillus sp. strain isolated from sea water is described. The protease is purified to homogeneity by ammonium sulphate precipitation and CM cellulose chromatography. The serine protease has a molecular mass of 29 kDa. Enzymatic characterization of protease revealed K(m) 2.22 mg mL(-1), Vmax 1111.11 U mL(-1), pH optimum 9.0, t1/2 190 min at 60°C and salt optima 1% (w/v) NaCl. The protease is remarkably stable in hydrophilic and hydrophobic solvents at high concentrations. The purified preparation is unstable at room temperature. Ca(2+) ions are required for preventing this loss of activity. Interestingly, the activity and stability are modulated differentially. Whereas, divalent cation Ca(2+) are involved in maintaining stability in solution at room temperature by preventing unfolding, monovalent Na(+) and K(+) ions participate in regulating the activity and assist in refolding of the enzyme. Application of the protease is shown in efficient removal of blood stain. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Anaerobic Oxidation of Methane Coupled to Nitrite Reduction by Halophilic Marine NC10 Bacteria.

    Science.gov (United States)

    He, Zhanfei; Geng, Sha; Cai, Chaoyang; Liu, Shuai; Liu, Yan; Pan, Yawei; Lou, Liping; Zheng, Ping; Xu, Xinhua; Hu, Baolan

    2015-08-15

    Anaerobic oxidation of methane (AOM) coupled to nitrite reduction is a novel AOM process that is mediated by denitrifying methanotrophs. To date, enrichments of these denitrifying methanotrophs have been confined to freshwater systems; however, the recent findings of 16S rRNA and pmoA gene sequences in marine sediments suggest a possible occurrence of AOM coupled to nitrite reduction in marine systems. In this research, a marine denitrifying methanotrophic culture was obtained after 20 months of enrichment. Activity testing and quantitative PCR (qPCR) analysis were then conducted and showed that the methane oxidation activity and the number of NC10 bacteria increased correlatively during the enrichment period. 16S rRNA gene sequencing indicated that only bacteria in group A of the NC10 phylum were enriched and responsible for the resulting methane oxidation activity, although a diverse community of NC10 bacteria was harbored in the inoculum. Fluorescence in situ hybridization showed that NC10 bacteria were dominant in the enrichment culture after 20 months. The effect of salinity on the marine denitrifying methanotrophic culture was investigated, and the apparent optimal salinity was 20.5‰, which suggested that halophilic bacterial AOM coupled to nitrite reduction was obtained. Moreover, the apparent substrate affinity coefficients of the halophilic denitrifying methanotrophs were determined to be 9.8 ± 2.2 μM for methane and 8.7 ± 1.5 μM for nitrite. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  15. Profile of antimicrobial susceptibility isolated microorganisms from hospitalized patients in PICU ward and detection of Methicillin-resistant Staphylococcus aureus and ESBL-producing bacteria by phenotypic methods

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    Shahla Abbas Poor

    2014-10-01

    Full Text Available Background: Hospital-acquired infections are a major challenge to patient. A range of gram-negative organisms are responsible for hospital-acquired infections, the Enterobacteriaceae family being the most commonly identified group overall. Infections by ESBL producers are associated with severe adverse clinical outcomes that have led to increased mortality, prolonged hospitalization, and rising medical costs. The aim of this study was to survey profile of antimicrobial susceptibility isolated microorganisms from hospitalized patients in PICU ward and detection of methicillin-resistant Staphylococcus aureus and ESBL-producing bacteria by phenotypic methods. Material and Methods: In this study participants were patients hospitalized in PICU part of Bahrami Hospital, Tehran, with attention to involved organ. For isolation of bacteria from patient’s samples, culture performed on different selective and differential media. After confirmation of bacteria by biochemical tests, susceptibility testing was performed by disc diffusion method. Phenotypic detection of MRSA strains was performed using cefoxcitin disc. ESBL producing strains were detected by ceftazidime (CAZ and ceftazidime/clavulanic acid (CAZ/CLA discs. Results: Among all isolated organisms from clinical samples, the most common isolated organisms were Escherichia coli (24 cases, Pseudomonas areoginosa (9 cases and Staphylococcus aureus (8 cases, respectively. Among eight MRSA isolated strains from different clinical samples, six strains (75% were MRSA. Among 52 isolated gram negative organisms, 5 strains (9/6% were ESBL. Conclusion: Standard interventions to prevent the transmission of antimicrobial resistance in health care facilities include hand hygiene, using barrier precautions in the care of colonized and infected patients, using dedicated instruments and equipment for these patients. The colonized or infected patients should be isolated in single rooms, multibed rooms or areas

  16. Influence of Natural Food Preservatives Combined with Gamma Radiation on Certain Microorganisms Isolated from Egyptian Juices

    International Nuclear Information System (INIS)

    El-Fouly, M.Z.; Hussein, H.A.; Abu El-Naga, M.N.; Haroun, B.M.

    2011-01-01

    Twelve strains were isolated from different Egyptian juices. The nine bacteria strains were identified as Micrococcus agilis, Staphylococcus aureus, S. warneri, S. epidermidis, S. auricularls, Bacillus sp., Pseudomonas aeruginosa, Citrobacter frundii, and Streptococcus pedococcus while the yeast strains were Debaryomyces sp., Kluveromyces sp .and Pichia sp. Three of the previous strains were chosen in the present work according to their common contamination in all samples and their characteristics; S. aureus represented gram positive bacteria, P. aeruginosa represented gram negative bacteria and Debaryomyces sp. to represent yeast strains. S. aureus has completely annihilated by 250 μ g/ml. of nisin, or 0.2% citric acid, or 0.15% lactic acid, or 1.2 % cinnamon or 5 kGy of gamma rays.; P. aeruginosa was destroyed by 0.3 % citric acid, or 0.3 % lactic acid, or 4 % cinnamon or 4 kGy of gamma rays, while Debaryomyces sp. was eliminated by 4 % citric acid, or 4.5 % lactic acid, or 2 % cinnamon or 7 kGy of gamma rays. Nisin alone has no effect on P. aeruginosa or Debaryomyces sp. Combined treatments have decreased both of natural preservatives and irradiation doses needed to eliminate the microorganisms contaminated the juices. S. aureus was completely eliminated by 3 kGy combined with only 25 μ g/ml. of nisin. The lethal dose decreased to 2 kGy by combination with citric, lactic acid and cinnamon at conc. 0.05%, 0.01% and 0.4 %, respectively .The dose level of gamma rays needed to eliminate P. aeruginosa decreased to 3 kGy in combination with citric acid 0.1% or with cinnamon 0.5 % and it decreased to 2 kGy by combination with lactic acid 0.1 %. In case of Debaryomyces sp the lethal dose decreased from 7 kGy to 4 kGy by combination with citric acid 1.5 % or cinnamon 1 % and to 3 kGy with lactic acid 1.5 %. Also, the combination treatment has activated the effect of nisin on both of P. aeruginosa and Debaryomyces sp. Dose level of 4 kGy combined with 200 μ g/ml. nisin

  17. Characterization of novel Bacillus strain N31 from mariculture water capable of halophilic heterotrophic nitrification-aerobic denitrification.

    Science.gov (United States)

    Huang, Fei; Pan, Luqing; Lv, Na; Tang, Xianming

    2017-11-01

    The development of an intensive aquaculture industry has been accompanied by increasing environmental impacts, especially nitrogen pollution. In this study, a novel halophilic bacterium capable of heterotrophic nitrification and aerobic denitrification was isolated from mariculture water and identified as Bacillus litoralis N31. The efficiency of ammonium, nitrite and nitrate removal by N31 were 86.3%, 89.3% and 89.4%, respectively, after a 48-h cultivation in sole N-source medium with initial nitrogen approximately 20 mg/L. However, ammonium was removed preferentially, and no obvious nitrite accumulated during the simultaneous nitrification and denitrification process in mixed N-source media. The existence of hao, napA and nirS genes further proved the heterotrophic nitrification-aerobic denitrification capability of N31. The optimal conditions for ammonium removal were 30°C, initial pH 7.5-8.5, C/N ratio 5-20 and salinity 30-40‰, and the nitrification rate of N31 increased with increasing initial [Formula: see text] from 10 to 250 mg/L. Biosecurity assessment with shrimp indicated that strain N31 could be applied in the marine aquaculture industry safely for culture water remediation and effluent treatment. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  18. Isolation, identification, and monitoring of antibiotic resistance in Pasteurella multocida and Mannheimia haemolytica isolated from sheep in East Azerbaijan province, Iran

    Directory of Open Access Journals (Sweden)

    I. Khalili

    2016-09-01

    Full Text Available The present study was carried out in order to isolate, identify, and assess the antimicrobial susceptibility of the causative agent(s of pneumonic pasteurellosis in sheep in East Azerbaijan province, northwest of Iran. Pneumonia was detected in 320 cases, and the affected lungs were sampled in the slaughterhouse. The samples were investigated bacteriologically for the isolation of two microorganisms from the Pasteurellaceae family. Pasteurella multocida was isolated from six (1.87% samples, while none of the lung tissues were positive for Mannheimia haemolytica. After the isolation and detection of microorganisms via cultural and morphological tests, the bacteria were identified on the basis of biochemical criteria and polymerase chain reaction (PCR technique. Antimicrobial susceptibility testing was performed on all P. multocida isolates, using broth microdilution method. Evaluation of the minimum inhibitory concentration (MIC of eight antimicrobial agents against the tested isolates showed that all the organisms were resistant to amoxicillin and relatively susceptible to ceftiofur. In conclusion, P. multocida was introduced as the main cause of ovine pneumonic pasteurellosis in the studied district, and the outbreak frequency significantly varied in different seasons of the year (P

  19. Characterization of a novel chitinase from a moderately halophilic bacterium, Virgibacillus marismortui strain M3-23

    OpenAIRE

    Essghaier, Badiaa; Hedi, Abdeljabbar; Bajji, Mohammed; Jijakli, Haissam; Boudabous, Abdellatif; Sadfi-Zouaoui, Najla

    2012-01-01

    A new chitinase produced by the moderately halophilic bacterium Virgibacillus marismortui strain M3- 23 was identified and characterized. Distinguishable characteristics of high activity and stability at different pH, temperatures and salinity of M3-23 chitinase are reported. Analysis of the catalytic domain sequence from the enzyme highlighted its relationship to glycosyl hydrolase family 18. Comparison of the deduced chitinase sequence from strain M3-23 to known chitinases from Bacillus spe...

  20. Metabolic Engineering of Microorganisms for the Production of Higher Alcohols

    Science.gov (United States)

    Choi, Yong Jun; Lee, Joungmin; Jang, Yu-Sin

    2014-01-01

    ABSTRACT Due to the increasing concerns about limited fossil resources and environmental problems, there has been much interest in developing biofuels from renewable biomass. Ethanol is currently used as a major biofuel, as it can be easily produced by existing fermentation technology, but it is not the best biofuel due to its low energy density, high vapor pressure, hygroscopy, and incompatibility with current infrastructure. Higher alcohols, including 1-propanol, 1-butanol, isobutanol, 2-methyl-1-butanol, and 3-methyl-1-butanol, which possess fuel properties more similar to those of petroleum-based fuel, have attracted particular interest as alternatives to ethanol. Since microorganisms isolated from nature do not allow production of these alcohols at high enough efficiencies, metabolic engineering has been employed to enhance their production. Here, we review recent advances in metabolic engineering of microorganisms for the production of higher alcohols. PMID:25182323

  1. Potential applications of plant probiotic microorganisms in agriculture and forestry

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    Luciana Porto de Souza Vandenberghe

    2017-07-01

    Full Text Available Agriculture producers, pushed by the need for high productivity, have stimulated the intensive use of pesticides and fertilizers. Unfortunately, negative effects on water, soil, and human and animal health have appeared as a consequence of this indiscriminate practice. Plant probiotic microorganisms (PPM, also known as bioprotectants, biocontrollers, biofertilizers, or biostimulants, are beneficial microorganisms that offer a promising alternative and reduce health and environmental problems. These microorganisms are involved in either a symbiotic or free-living association with plants and act in different ways, sometimes with specific functions, to achieve satisfactory plant development. This review deals with PPM presentation and their description and function in different applications. PPM includes the plant growth promoters (PGP group, which contain bacteria and fungi that stimulate plant growth through different mechanisms. Soil microflora mediate many biogeochemical processes. The use of plant probiotics as an alternative soil fertilization source has been the focus of several studies; their use in agriculture improves nutrient supply and conserves field management and causes no adverse effects. The species related to organic matter and pollutant biodegradation in soil and abiotic stress tolerance are then presented. As an important way to understand not only the ecological role of PPM and their interaction with plants but also the biotechnological application of these cultures to crop management, two main approaches are elucidated: the culture-dependent approach where the microorganisms contained in the plant material are isolated by culturing and are identified by a combination of phenotypic and molecular methods; and the culture-independent approach where microorganisms are detected without cultivating them, based on extraction and analyses of DNA. These methods combine to give a thorough knowledge of the microbiology of the studied

  2. Isolation of Geobacter species from diverse sedimentary environments

    Science.gov (United States)

    Coaxes, J.D.; Phillips, E.J.P.; Lonergan, D.J.; Jenter, H.; Lovley, D.R.

    1996-01-01

    In an attempt to better understand the microorganisms responsible for Fe(III) reduction in sedimentary environments, Fe(III)-reducing microorganisms were enriched for and isolated from freshwater aquatic sediments, a pristine deep aquifer, and a petroleum-contaminated shallow aquifer. Enrichments were initiated with acetate or toluene as the electron donor and Fe(III) as the electron acceptor. Isolations were made with acetate or benzoate. Five new strains which could obtain energy for growth by dissimilatory Fe(III) reduction were isolated. All five isolates are gram- negative strict anaerobes which grow with acetate as the electron donor and Fe(III) as the electron acceptor. Analysis of the 16S rRNA sequence of the isolated organisms demonstrated that they all belonged to the genus Geobacter in the delta subdivision of the Proteobacteria. Unlike the type strain, Geobacter metallireducens, three of the five isolates could use H2 as an electron donor fur Fe(III) reduction. The deep subsurface isolate is the first Fe(III) reducer shown to completely oxidize lactate to carbon dioxide, while one of the freshwater sediment isolates is only the second Fe(III) reducer known that can oxidize toluene. The isolation of these organisms demonstrates that Geobacter species are widely distributed in a diversity of sedimentary environments in which Fe(III) reduction is an important process.

  3. Application of halophilic nuclease H of Micrococcus varians subsp. halophilus to commercial production of flavoring agent 5'-GMP.

    Science.gov (United States)

    Kamekura, M; Hamakawa, T; Onishi, H

    1982-01-01

    RNA was degraded at 60 degrees C for 24 h by halophilic nuclease H in supernatants from broth cultures of Micrococcus varians subsp. halophilus containing 12% NaCl. Since contaminating 5'-nucleotidase exhibited almost no activity under these conditions, the 5'-GMP formed could be recovered from the reaction mixture, and the yield was 805 mg from 5 g of RNA. PMID:6184020

  4. Effects of Atrazine on Soil Microorganisms

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    Ljiljana Radivojević

    2006-01-01

    Full Text Available Effects of the herbicide atrazine on soil microorganisms was investigated. Trials were set up in laboratory, on a clay loam soil. Atrazine was applied at 8.0, 40.0 and 80.0 mg/kg soil rates. The abundance of total microorganisms, fungi, actinomycetes, cellulolytic microorganisms and amino-heterotrophs was recorded. Soil samples were collected 1, 7, 14, 21, 30 and 60 days after atrazine treatment for microbiological analyses.The results showed that the intensity of atrazine effect on soil microorganisms depended on treatment rate, exposure time and group of microorganisms. Atrazine had an inhibiting effect on cellulolytic microorganisms and amino-heterotrophs. Initially, it inhibited fungiand actinomycetes but its effect turned into a stimulating one once a population recovered. Atrazine had a stimulating effect on total abundance of microorganisms.

  5. [Effects of copper on biodegradation mechanism of trichloroethylene by mixed microorganisms].

    Science.gov (United States)

    Gao, Yanhui; Zhao, Tiantao; Xing, Zhilin; He, Zhi; Zhang, Lijie; Peng, Xuya

    2016-05-25

    We isolated and enriched mixed microorganisms SWA1 from landfill cover soils supplemented with trichloroethylene (TCE). The microbial mixture could degrade TCE effectively under aerobic conditions. Then, we investigated the effect of copper ion (0 to 15 μmol/L) on TCE biodegradation. Results show that the maximum TCE degradation speed was 29.60 nmol/min with 95.75% degradation when copper ion was at 0.03 μmol/L. In addition, genes encoding key enzymes during biodegradation were analyzed by Real-time quantitative reverse transcription PCR (RT-qPCR). The relative expression abundance of pmoA gene (4.22E-03) and mmoX gene (9.30E-06) was the highest when copper ion was at 0.03 μmol/L. Finally, we also used MiSeq pyrosequencing to investigate the diversity of microbial community. Methylocystaceae that can co-metabolic degrade TCE were the dominant microorganisms; other microorganisms with the function of direct oxidation of TCE were also included in SWA1 and the microbial diversity decreased significantly along with increasing of copper ion concentration. Based on the above results, variation of copper ion concentration affected the composition of SWA1 and degradation mechanism of TCE. The degradation mechanism of TCE included co-metabolism degradation of methanotrophs and oxidation metabolism directly at copper ion of 0.03 μmol/L. When copper ion at 5 μmol/L (biodegradation was 84.75%), the degradation mechanism of TCE included direct-degradation and co-metabolism degradation of methanotrophs and microorganisms containing phenol hydroxylase. Therefore, biodegradation of TCE by microorganisms was a complicated process, the degradation mechanism included co-metabolism degradation of methanotrophs and bio-oxidation of non-methanotrophs.

  6. VISUALIZATION OF BIOCHEMICAL ACTIVITY OF MICROORGANISMS GENUS AEROCOCCUS SPECIES AEROCOCCUS VIRIDANS

    Directory of Open Access Journals (Sweden)

    Stepansky DO

    2016-03-01

    Full Text Available Introduction. Aerococci are catalase-negative Gram-positive microorganisms, widespread in the environment, in the cold-blooded microbiocenoses [1, 2] and warm-blooded organisms [3]. Currently, there are seven species of the Aerococcus genus [4]. Type A. viridans got its name as a result of greening blood agar around the growing colonies. It was found that one of the products of A. viridans growth is hydrogen peroxide, has an antagonistic effect on various kinds of bacteria "in vitro" and "in vivo" [5]. It was subsequently found that hydrogen peroxide and superoxide radical are produced as a result of NAD-independent lactatoxidase [6,7] and piruvatoxidase functioning[8]. The oxidative ability of A. viridans is a distinctive feature and allows to visualize these properties using a specific indicator medium [9]. We have developed an indicator that enables to visualize oxidation and reduction properties of aerococci. Material & methods. Auto-symbiotic cultures of A. viridans was used for studying of oxidase - reductase activity, inoculated from human body, an industrial strain of A. viridans 167, used for the preparation of "A-bacterin", culture of Aureobasidium pullulans B5, isolated from the soil and having glucose oxidase activity [10]. Designed indicating medium were also tested in the inoculation of aerococci crops, having lactatoxidase activity of biomaterials from birds and mammals. As a basis for the indicating media (IM IM1 media was selected with following composition (g per 1 liter of water Iodide / potassium 26.0 Soluble starch 10.0 Nutrient agar 30.0 For visualization of oxidase-reductase activity of aerococci acellular components IM4 was developed based on IM3, in which distilled water after double purification was used instead of tap water and highly purified agar-agar was used instead of standard nutrient agar. Results & discussion. IM1 is used to test the oxidative properties of aerococci crops. IM manifests the appearance of a dark

  7. [Studies on metabolites from marine microorganism Aspergillus terreus collected from nature reserve region of mangrove].

    Science.gov (United States)

    Shen, Yi; Zou, Jianhua; Dai, Jungui

    2011-09-01

    To search for new antitumor active lead compounds from marine microorganism. A marine strain, Aspergillus terreus, was cultured and up-scaled in artificial seawater media, from which the metabolites were isolated and elucidated by using modern spectroscopy techniques. Twelve compounds were isolated from mycelia and fermentation broth of A. terreus. Compounds 1-4 were steroids, compounds 5-8 were organic acids and esters, compound 9 was an alkaloid, compound 10 was an isocoumarin, compound 11 was ceramide, compound 12 was propenyl cyclic pentanediol.

  8. Nonspecific Bacterial Flora Isolated from the Body Surface and Inside Ixodes ricinus Ticks.

    Science.gov (United States)

    Okła, Hubert; Sosnowska, Malwina; Jasik, Krzysztof P; Słodki, Jan; Wojtyczka, Robert D

    2012-09-28

    Ixodes ricinus and other representatives of the order Ixodida are vectors of typical pathogens: Borrelia burgdorferi sensu lato, Anaplasma phagocytophilium, Babesia spp., a tick-borne encephalitis virus, and other microorganisms which are important from a medical and veterinary point of view. The presented study focuses on the verification of nonspecific bacterial flora of I. ricinus. We analyzed ticks collected in a forest region in Silesia, an industrial district in Poland. Methods of classical microbiology and biochemical assays (API 20 NE test, API Staph test and MICRONAUT System) were used for isolation and identification of microorganisms living on the body surface of I. ricinus and inside ticks. The results show the presence of various bacteria on the surface and inside ticks' bodies. During the study, we isolated Acinetobacter lwoffi, Pseudomonas fluorescens, Aeromonas hydrophila, Achromobacter denitrificans, Alcaligenes faecalis, Stenotrophomonas maltophilia, Pseudomonas oryzihabitans, Micrococcus spp., Kocuria varians, Staphylococcus lentus, Kocuria kristinae, Streptococcus pneumoniae, Rhizobium radiobacter, Staphylococcus xylosus. Majority of the isolated species are non-pathogenic environmental microorganisms, but some of the isolated bacterial strains could cause severe infections.

  9. Biotransformation of Spanish coals by microorganisms; Biotransformacion de Carbones Espanoles por Microorganismos

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    some newly isolated microorganisms could solubilized different kinds of Spanish coals (hard coal, subbituminous coal and lignite). Certain fungi and bacteria could solubilized lignite when growing in a mineral medium. However, to solubilized higher rank coals (hard coal and subbituminous coal) microorganisms require a complete medium. Microorganisms, which showed higher capacity to solubilized coal, were incubated in the presence of coal (hard coal, subbituminous coal and lignite) at the optimal conditions to get coal liquefaction/solubilization. The resultant products were analysed by IR and UV/visible spectrometry. No major differences among the original coal, solubilized/liquefied coal and residual coal were detected. However, an increase in metallic carboxylate and a decrease in OH'- carboxylic groups were observed in the liquefied lignite. Humic acids derived from original lignite residual lignite and liquefied/solubilized lignite by microorganisms were analysed. Several differences were observed in the humic acids extracted from the liquefied lignite, such as an increase in the total acidity and in the proportion of the phenolic groups. Differences on the humic acid molecular weight were observed too. Several fungal and bacterial strains were able to grow using humic acids as sole carbon source. Microorganisms growing in humic acid were observed by Scanning Electron Microscopy. Besides, the coal solubilization capacity of several fungal strains (M2, m$ and AGI) growing in different culture media was assayed. In order to get some insight into the mechanisms of the liquefaction/solubilization of Spanish coals (hard coal, subbituminous coal and lignite) by these microorganisms, some features in the culture supernatants were studied: pH values; extracellular specific proteins; enzyme activities possibly related with coal solubilization and the presence of oxalate. M2 and M4 fungal strains grown in the presence of coal produced some specific extracellular proteins

  10. Biotransformation of Spanish coals by microorganisms; Biotransformacion de Carbones Espanoles por Microorganismos

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2000-07-01

    some newly isolated microorganisms could solubilized different kinds of Spanish coals (hard coal, subbituminous coal and lignite). Certain fungi and bacteria could solubilized lignite when growing in a mineral medium. However, to solubilized higher rank coals (hard coal and subbituminous coal) microorganisms require a complete medium. Microorganisms, which showed higher capacity to solubilized coal, were incubated in the presence of coal (hard coal, subbituminous coal and lignite) at the optimal conditions to get coal liquefaction/solubilization. The resultant products were analysed by IR and UV/visible spectrometry. No major differences among the original coal, solubilized/liquefied coal and residual coal were detected. However, an increase in metallic carboxylate and a decrease in OH'- carboxylic groups were observed in the liquefied lignite. Humic acids derived from original lignite residual lignite and liquefied/solubilized lignite by microorganisms were analysed. Several differences were observed in the humic acids extracted from the liquefied lignite, such as an increase in the total acidity and in the proportion of the phenolic groups. Differences on the humic acid molecular weight were observed too. Several fungal and bacterial strains were able to grow using humic acids as sole carbon source. Microorganisms growing in humic acid were observed by Scanning Electron Microscopy. Besides, the coal solubilization capacity of several fungal strains (M2, m$ and AGI) growing in different culture media was assayed. In order to get some insight into the mechanisms of the liquefaction/solubilization of Spanish coals (hard coal, subbituminous coal and lignite) by these microorganisms, some features in the culture supernatants were studied: pH values; extracellular specific proteins; enzyme activities possibly related with coal solubilization and the presence of oxalate. M2 and M4 fungal strains grown in the presence of coal produced some specific extracellular

  11. Microorganisms in food technology

    Energy Technology Data Exchange (ETDEWEB)

    Rose, A H

    1981-11-01

    Man has been using microorganisms for thousands of years to make bread, cheese, beer, wine, etc. Today, microorganisms can be specially grown or genetically manipulated so as to synthesize high-quality proteins even from low-grade basic materials.

  12. Fossil Microorganisms in Archaean

    Science.gov (United States)

    Astafleva, Marina; Hoover, Richard; Rozanov, Alexei; Vrevskiy, A.

    2006-01-01

    Ancient Archean and Proterozoic rocks are the model objects for investigation of rocks comprising astromaterials. The first of Archean fossil microorganisms from Baltic shield have been reported at the last SPIE Conference in 2005. Since this confeence biomorphic structures have been revealed in Archean rocks of Karelia. It was determined that there are 3 types of such bion structures: 1. structures found in situ, in other words microorganisms even-aged with rock matrix, that is real Archean fossils biomorphic structures, that is to say forms inhabited early formed rocks, and 3. younger than Archean-Protherozoic minerali microorganisms, that is later contamination. We made attempt to differentiate these 3 types of findings and tried to understand of burial of microorganisms. The structures belongs (from our point of view) to the first type, or real Archean, forms were under examination. Practical investigation of ancient microorganisms from Green-Stone-Belt of Northern Karelia turns to be very perspective. It shows that even in such ancient time as Archean ancient diverse world existed. Moreover probably such relatively highly organized cyanobacteria and perhaps eukaryotic formes existed in Archean world.

  13. Biosurfactants from marine microorganisms

    Directory of Open Access Journals (Sweden)

    Suppasil Maneerat

    2005-11-01

    Full Text Available Biosurfactants are the surface-active molecules synthesized by microorganisms. With the advantage of environmental compatibility, the demand for biosurfactants has been steadily increasing and may eventually replace their chemically synthesized counterparts. Marine biosurfactants produced by some marine microorganisms have been paid more attention, particularly for the bioremediation of the sea polluted by crude oil. This review describes screening of biosurfactant-producing microorganisms, the determination of biosurfactant activity as well as the recovery of marine surfactant. The uses of marine biosurfactants for bioremediation are also discussed.

  14. Crude oil degradation by Bacillus and Micrococcus species isolated ...

    African Journals Online (AJOL)

    Microorganisms capable of degrading crude oil were isolated from soil compost in Kano, northwestern Nigeria. The work was carried out with the aim of determining crude-oil biodegradation potentials of Bacillus and Micrococcus species isolated from the soil compost as well as the assessment of the applicability of ...

  15. Classification of root canal microorganisms using electronic-nose and discriminant analysis

    Directory of Open Access Journals (Sweden)

    Özbilge Hatice

    2010-11-01

    Full Text Available Abstract Background Root canal treatment is a debridement process which disrupts and removes entire microorganisms from the root canal system. Identification of microorganisms may help clinicians decide on treatment alternatives such as using different irrigants, intracanal medicaments and antibiotics. However, the difficulty in cultivation and the complexity in isolation of predominant anaerobic microorganisms make clinicians resort to empirical medical treatments. For this reason, identification of microorganisms is not a routinely used procedure in root canal treatment. In this study, we aimed at classifying 7 different standard microorganism strains which are frequently seen in root canal infections, using odor data collected using an electronic nose instrument. Method Our microorganism odor data set consisted of 5 repeated samples from 7 different classes at 4 concentration levels. For each concentration, 35 samples were classified using 3 different discriminant analysis methods. In order to determine an optimal setting for using electronic-nose in such an application, we have tried 3 different approaches in evaluating sensor responses. Moreover, we have used 3 different sensor baseline values in normalizing sensor responses. Since the number of sensors is relatively large compared to sample size, we have also investigated the influence of two different dimension reduction methods on classification performance. Results We have found that quadratic type dicriminant analysis outperforms other varieties of this method. We have also observed that classification performance decreases as the concentration decreases. Among different baseline values used for pre-processing the sensor responses, the model where the minimum values of sensor readings in the sample were accepted as the baseline yields better classification performance. Corresponding to this optimal choice of baseline value, we have noted that among different sensor response model and

  16. Production of Microbial Protease from Selected Soil Fungal Isolates ...

    African Journals Online (AJOL)

    Production of Microbial Protease from Selected Soil Fungal Isolates. ... Nigerian Journal of Biotechnology ... and 500C. The optimal pH on the enzyme production was observed to be between pH 3.5 and 5.5 for the organisms. Keywords: Soil microorganism, fungal isolate, incubation period, microbial enzyme. Nig J. Biotech.

  17. Characterization of four Paenibacillus species isolated from pasteurized, chilled ready-to-eat meals

    NARCIS (Netherlands)

    Helmond, Mariette; Nierop Groot, Masja N.; Bokhorst-van de Veen, van Hermien

    2017-01-01

    Food spoilage is often caused by microorganisms. The predominant spoilage microorganisms of pasteurized, chilled ready-to-eat (RTE) mixed rice-vegetable meals stored at 7 °C were isolated and determined as Paenibacillus species. These sporeforming psychrotrophic bacteria are well adapted to grow

  18. Isolation and identification of radiation resistant yeasts from sea water

    International Nuclear Information System (INIS)

    Park, Jong Cheon; Jeong, Yong Uk; Kim, Du Hong; Jo, Eun A

    2011-12-01

    This study was conducted to isolate radiation-resistant yeasts from sea water for development of application technology of radiation-resistant microorganism. · Isolation of 656 yeasts from sea water and selection of 2 radiation-resistant yeasts (D 10 value >3) · Identification of isolated yeasts as Filobasidium elegans sharing 99% sequence similarity · Characterization of isolated yeast with ability to repair of the DNA damage and membrane integrity to irradiation

  19. Halotolerant and halophilic bacteria in the oceans of the icy satellites

    Science.gov (United States)

    Ramirez, S. I.; Montoya, L.; Avendaño, R.

    2013-05-01

    Halotolerant and halophilic prokaryotes require salt concentrations equal to or higher than those present at terrestrial oceans (Rothschild and Mancinelli, 2001). They are a particular kind of extremophiles and as expected, their halotolerance is mainly expressed in terms of a certain NaCl percentage, at least on Earth. With the discovery of putative salty liquid oceans beneath the iced surfaces of some of the satellites of Jupiter and Saturn (Mueller and McKinnon, 1988; Kargel et al., 2000; Zolotov, 2007), information about the impact of other types of salts, different from NaCl, on the growth of complex biological systems is necessary. We have found that when three specific bacteria strains are growing in media enriched with salts containing chaotropic and kosmotropic ions, their specific optimal growth value is modified (Montoya et al., 2010). The changes can be broadly explained in terms of the Hofmeister series (Zhang and Cremer, 2006). These results can be used to infer an extension in the limits of biological activity. For terrestrial organisms there is scarce information to determine the impact of another salt in the growth of an organism. In these sense we have found that when media enriched with magnesium sulfate (MgSO4) at water activity values (aw) similar to those reported as optimal for NaCl, their growth and tolerance is considerably enhanced. On the other hand, the combination of chaotropic and kosmotropic ions result in salts of astrobiological importance such as the sulphate already mentioned, carbonates or chlorides that can tentatively exist in the putative ocean of Europa, Ganymedes, or Enceladus or even at the subsurface of Mars. In this frame, we studied the growth rate of Halomonas halodurans, H. magadiensis and Bacillus pumillus when exposed to media enriched with NaCl, MgSO4, Mg(NO3)2, MgCl2, Na2SO4 and NH4SO4. Equivalent values of water activity (aw) for each salt were compared and correlated with microbial activity (Montoya et al., 2010

  20. Waste drilling-fluid-utilising microorganisms in a tropical mangrove swamp oilfield location

    Energy Technology Data Exchange (ETDEWEB)

    Benka-Coker, M.O.; Olumagin, A. [Benin Univ. (Nigeria). Dept. of Microbiology

    1995-12-31

    Waste drilling-fluid-utilising microorganisms were isolated from drilling-mud cuttings, soil and creek water from a mangrove swamp oilfield location in the Delta area of Nigeria using waste drilling-fluid as the substrate. Eighteen bacterial isolates obtained were identified as species of Staphylococcus, Acinetobacter, Alcaligenes, Serratia, Clostridium, Enterobacter, Klebsiella, Nocardia, Bacillus, Actinomyces, Micrococcus and Pseudomonas, while the genera of fungi isolated were Penicillium, Cladosporium and Fusarium. Even though drilling-fluid-utilising genera were in higher numbers in the soil than in the two other sources examined, the percentages of the total heterotrophic bacteria that utilised waste drilling-fluid were 6.02 in the drilling-mud cuttings, 0.83 in creek water and 0.42 in soil. The screen tests for biodegradation potential of the bacterial isolates showed that, even though all the isolates were able to degrade and utilise the waste fluid for growth, species of Alcaligenes and Micrococcus were more active degraders of the waste. The significance of the results in environmental management in oil-producing areas of Nigeria is discussed. (Author)