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Sample records for lightning-competent pseudomonas sp

  1. Biodegradation of resorcinol by Pseudomonas sp.

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    Nader Hajizadeh

    2016-11-01

    Full Text Available Objective: To investigate the ability of Pseudomonas sp. isolated from East Azarbaijan, Iran in bioremediation of resorcinol. Methods: Resorcinol biodegradation was evaluated using spectrophotometry and confirmed by gas chromatography-mass spectroscopy. Results: This isolate was able to remove up to 37.12% of resorcinol from contaminated water. Reusability experiments had confirmed the biodegradation process which produced seven intermediate compounds. These intermediates were characterized by gas chromatographymass spectroscopy technique. The products of resorcinol biodegradation were apparently 1, 4-cyclohexadiene, nonadecene, 2-heptadecanone, 1-isopropyl-2-methoxy-4-methylbenzene, hexadecanoic acid, 9-octadecenoic acid, phenol and 5-methyl-2-(1-methylethyl. Conclusions: The findings revealed that Pseudomonas sp. is able to degrade resorcinol. Because of being an indigenous organism, this isolate is more compatible with the climate of the northwest region of Iran and possibly will be used for degradation of other similar aromatic compounds.

  2. Biodegradation of resorcinol byPseudomonas sp.

    Institute of Scientific and Technical Information of China (English)

    Nader Hajizadeh; Najibeh Shirzad; Ali Farzi; Mojtaba Salouti; Azra Momeni

    2016-01-01

    ABSTRACT Objective:To investigate the ability ofPseudomonas sp. isolated from East Azarbaijan, Iran in bioremediation of resorcinol. Methods: Resorcinol biodegradation was evaluated using spectrophotometry and confirmed by gas chromatography-mass spectroscopy. Results:This isolate was able to remove up to 37.12% of resorcinol from contaminated water. Reusability experiments had confirmed the biodegradation process which produced seven intermediate compounds. These intermediates were characterized by gas chromatography-mass spectroscopy technique. The products of resorcinol biodegradation were apparently 1, 4-cyclohexadiene, nonadecene, 2-heptadecanone, 1-isopropyl-2-methoxy-4-methylbenzene, hexadecanoic acid, 9-octadecenoic acid, phenol and 5-methyl-2-(1-methylethyl). Conclusions: The findings revealed thatPseudomonas sp. is able to degrade resorcinol. Because of being an indigenous organism, this isolate is more compatible with the climate of the northwest region of Iran and possibly will be used for degradation of other similar aromatic compounds.

  3. Complete Genome Sequence of Pseudomonas sp. UK4, a Model Organism for Studies of Functional Amyloids in Pseudomonas

    DEFF Research Database (Denmark)

    Dueholm, Morten Simonsen; Danielsen, Heidi Nolsøe; Nielsen, Per Halkjær

    2014-01-01

    Here, we present the complete genome of Pseudomonas sp. UK4. This bacterium was the first Pseudomonas strain shown to produce functional amyloids, and it represents a model organism for studies of functional amyloids in Pseudomonas (Fap).......Here, we present the complete genome of Pseudomonas sp. UK4. This bacterium was the first Pseudomonas strain shown to produce functional amyloids, and it represents a model organism for studies of functional amyloids in Pseudomonas (Fap)....

  4. Draft Genome Sequences of the Antimicrobial Producers Pseudomonas sp. TAA207 and Pseudomonas sp. TAD18 Isolated from Antarctic Sediments

    Science.gov (United States)

    Presta, Luana; Inzucchi, Ilaria; Bosi, Emanuele; Fondi, Marco; Perrin, Elena; Maida, Isabel; Miceli, Elisangela; Tutino, Maria Luisa; Lo Giudice, Angelina; de Pascale, Donatella

    2016-01-01

    We report here the draft genome sequence of the Pseudomonas sp. TAA207 and Pseudomonas sp. TAD18 strains, isolated from Antarctic sediments during a summer campaign near coastal areas of Terra Nova Bay (Antarctica). Genome sequence knowledge allowed the identification of genes associated with the production of bioactive compounds and antibiotic resistance. Furthermore, it will be instrumental for comparative genomics and the fulfillment of both basic and application-oriented investigations. PMID:27469957

  5. OXIDATION OF POLYCHLORINATED BIPHENYLS BY PSEUDOMONAS SP. STRAIN LB400 AND PSEUDOMONAS PSEUDOALCALIGENES KF707

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    Biphenyl-grown cells and cell extracts prepared from biphenyl-grown cells of Pseudomonas sp. strain LB400 oxidize a much wider range of chlorinated biphenyls than do analogous preparations from Pseudomonas pseudoalcaligenes KF707. These results are attributed to differences in th...

  6. Pseudomonas matsuisoli sp. nov., isolated from a soil sample.

    Science.gov (United States)

    Lin, Shih-Yao; Hameed, Asif; Hung, Mei-Hua; Liu, You-Cheng; Hsu, Yi-Han; Young, Li-Sen; Young, Chiu-Chung

    2015-03-01

    An aerobic, Gram-stain-negative, rod-shaped and polar-flagellated bacterium, designated strain CC-MHH0089(T), was isolated from a soil sample taken on Matsu Island (Taiwan). Strain CC-MHH0089(T) grew at 15-30 °C and pH 5.0-10.0 and tolerated ≤8 % (w/v) NaCl. 16S rRNA gene sequence analysis showed high pairwise sequence similarity to Pseudomonas azotifigens 6H33b(T) (97.3 %) and Pseudomonas balearica SP1402(T) (96.7 %) and lower sequence similarity to other strains (Pseudomonas, for which the name Pseudomonas matsuisoli sp. nov. is proposed. The type strain is CC-MHH0089(T) ( = BCRC 80771(T) = JCM 30078(T)).

  7. Uji produksi biosurfaktan oleh Pseudomonas sp. pada substrat yang berbeda

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    Fatimah Fatimah

    2012-02-01

    Full Text Available Biosurfactant, microbial metabolite whose properties like surfactant, was suggested to replace chemically synthesized surfactant for take in hand environtmental pollution by petroleum hydrocarbon. This work was done to examine potency of Pseudomonas sp. isolated from Tanjung Perak Harbor to produce biosurfactant. Also, to know the effect of different substrates (glucose + yeast extract, lubricating oil and hexadecane toward biosurfactant production. Pseudomonas sp. grown in mineral synthetic water and biosurfactant production was measured on stationary phase. Biosurfactant production based on emulsification activity and surface tension reduction of supernatant (using Du Nouy tensiometer. Solar, lubricating oil, and hexadecane were used to examine emulsification activity. Results indicated that Pseudomonas sp. have a potency to produce biosurfactant. Surface tension of supernatant decreased up to 20 dyne/cm, when grown on hexadecane substrate. Hexadecane is the best growing substrate for biosurfactant production than others.

  8. Pseudomonas helmanticensis sp. nov., isolated from forest soil.

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    Ramírez-Bahena, Martha-Helena; Cuesta, Maria José; Flores-Félix, José David; Mulas, Rebeca; Rivas, Raúl; Castro-Pinto, Joao; Brañas, Javier; Mulas, Daniel; González-Andrés, Fernando; Velázquez, Encarna; Peix, Alvaro

    2014-07-01

    A bacterial strain, OHA11(T), was isolated during the course of a study of phosphate-solubilizing bacteria occurring in a forest soil from Salamanca, Spain. The 16S rRNA gene sequence of strain OHA11(T) shared 99.1% similarity with respect to Pseudomonas baetica a390(T), and 98.9% similarity with the type strains of Pseudomonas jessenii, Pseudomonas moorei, Pseudomonas umsongensis, Pseudomonas mohnii and Pseudomonas koreensis. The analysis of housekeeping genes rpoB, rpoD and gyrB confirmed its phylogenetic affiliation to the genus Pseudomonas and showed similarities lower than 95% in almost all cases with respect to the above species. Cells possessed two polar flagella. The respiratory quinone was Q9. The major fatty acids were C16 : 0, C18 : 1ω7c and summed feature 3 (C16 : 1ω7c/iso-C15 : 0 2-OH). The strain was oxidase-, catalase- and urease-positive, positive for arginine dihydrolase but negative for nitrate reduction, β-galactosidase production and aesculin hydrolysis. It was able to grow at 31 °C and at pH 11. The DNA G+C content was 58.1 mol%. DNA-DNA hybridization results showed values lower than 49% relatedness with respect to the type strains of the seven closest related species. Therefore, the combined genotypic, phenotypic and chemotaxonomic data support the classification of strain OHA11(T) to a novel species of the genus Pseudomonas, for which the name Pseudomonas helmanticensis sp. nov. is proposed. The type strain is OHA11(T) ( = LMG 28168(T) = CECT 8548(T)).

  9. Pseudomonas soli sp. nov., a novel producer of xantholysin congeners.

    Science.gov (United States)

    Pascual, Javier; García-López, Marina; Carmona, Cristina; Sousa, Thiciana da S; de Pedro, Nuria; Cautain, Bastien; Martín, Jesús; Vicente, Francisca; Reyes, Fernando; Bills, Gerald F; Genilloud, Olga

    2014-09-01

    A chemoorganotrophic Gram-negative bacterium was isolated by means of a diffusion sandwich system from a soil sample from the Sierra Nevada National Park, Spain. Strain F-279,208(T) was oxidase and catalase positive, strictly aerobic, non-spore-forming and motile by single polar flagellum. Phylogenetic analysis of the 16S rRNA, gyrB, rpoB and rpoD genes revealed that strain F-279,208(T) belongs to the Pseudomonas putida group with Pseudomonas mosselii and Pseudomonas entomophila as its closest relatives. DNA-DNA hybridization assays and phenotypic traits confirmed that this strain belongs to a novel species of the genus Pseudomonas, for which the name Pseudomonas soli sp. nov. is proposed. The type strain is F-279,208(T) (=DSM 28043(T)=LMG 27941(T)), and during fermentation it produces xantholysins, a family of lipodepsipeptides. The major compound, xantholysin A, showed an interesting activity in a RCC4 kidney tumor cell line with inactivation of VHL linked with the HIF pathway, without any cytotoxic effects against other human tumor cell lines tested including, liver, pancreas and breast.

  10. Pseudomonas asturiensis sp. nov., isolated from soybean and weeds.

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    González, Ana J; Cleenwerck, Ilse; De Vos, Paul; Fernández-Sanz, Ana M

    2013-07-01

    Five strains of gram negative bacteria, isolated from soybean (LPPA 221(T), 222 and 223) and weeds (LPPA 816 and 1442), were analyzed by a polyphasic approach. The isolates showed variation in their phenotypic traits and were placed in the Pseudomonas fluorescens lineage, based on 16S rRNA gene sequence phylogeny, as a single but well separated cluster. MLSA analysis based on gyrB and rpoD sequences clustered the strains in a single branch in the Pseudomonas syringae group, and revealed P. viridiflava as closest relative. DNA-DNA hybridizations showed medium levels of DNA-DNA relatedness with the type strain of P. viridiflava (50%) and lower levels (<32%) with other type strains of the P. syringae group, supporting classification within a novel species of the genus Pseudomonas. The strains can be distinguished from species of the P. syringae group by the fatty acid C17:0 cyclo that is present in a low amount (2.5%) and from P. viridiflava by their inability to assimilate d-tartrate and d-sorbitol, and by the formation of red colonies on TTC medium. For this new species, the name Pseudomonas asturiensis sp. nov. is proposed. The type strain is LPPA 221(T) (=LMG 26898(T)=CECT 8095(T)).

  11. Pseudomonas zhaodongensis sp. nov., isolated from saline and alkaline soils.

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    Zhang, Lei; Pan, Yuanyuan; Wang, Kaibiao; Zhang, Xiaoxia; Zhang, Cheng; Zhang, Shuang; Fu, Xiaowei; Jiang, Juquan

    2015-03-01

    Strain NEAU-ST5-21(T) was isolated from saline and alkaline soils in Zhaodong City, Heilongjiang Province, China. It was aerobic, Gram-stain-negative, rod-shaped and motile with a polar flagellum. It produced yellow-orange colonies with a smooth surface, and grew in the presence of 0-5 % (w/v) NaCl (optimum 0 %, w/v), at temperatures of 20-40 °C (optimum 28 °C) and at pH 7-11 (optimum pH 7). Phylogenetic analyses based on the separate 16S rRNA gene sequences and concatenated 16S rRNA, gyrB and rpoD gene sequences indicated that strain NEAU-ST5-21(T) belongs to the genus Pseudomonas in the class Gammaproteobacteria. The most closely related species is Pseudomonas xanthomarina, whose type strain (KMM 1447(T)) showed gene sequence similarities of 99.0 % for 16S rRNA, 81.8 % for gyrB and 85.0 % for rpoD with strain NEAU-ST5-21(T). DNA-DNA hybridization values between strain NEAU-ST5-21(T) and P. xanthomarina DSM 18231(T), Pseudomonas kunmingensis CGMCC 1.12273(T), Pseudomonas stutzeri DSM 5190(T), Pseudomonas oleovorans subsp. lubricantis DSM 21016(T), Pseudomomas chengduensis CGMCC 2318(T), Pseudomonas alcaliphila DSM 17744(T) and Pseudomonas toyotomiensis DSM 26169(T) were 52±0 % to 25±2 %. The DNA G+C content of strain NEAU-ST5-21(T) was 65 mol%. The major fatty acids (>10 %) were C18 : 1ω7c and/or C18 : 1ω6c, C16 : 1ω7c and/or C16 : 1ω6c and C16 : 0, the predominant respiratory quinone was ubiquinone 9, and polar lipids consisted of diphosphatidylglycerol, phosphatidylethanolamine, one unknown phospholipid, phosphatidylglycerol, one unknown aminolipid, one unknown lipid and a glycolipid. The proposed name is Pseudomonas zhaodongensis sp. nov., NEAU-ST5-21(T) ( = ACCC 06362(T) = DSM 27559(T)) being the type strain.

  12. Mineralization of a Malaysian crude oil by Pseudomonas sp. and Achromabacter sp. isolated from coastal waters

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, J.; Ahmad, M.F.

    1995-12-31

    Regarded as being a potentially effective tool to combat oil pollution, bioremediation involves mineralization, i.e., the conversion of complex hydrocarbons into harmless CO{sub 2} and water by action of microorganisms. Therefore, in achieving optimum effectiveness from the application of these products on crude oil in local environments, the capability of the bacteria to mineralize hydrocarbons was evaluated. The microbial laboratory testing of mineralization on local oil degraders involved, first, isolation of bacteria found at a port located on the west coast of Peninsular Malaysia. Subsequently, these bacteria were identified by means of Biomereux`s API 20E and 20 NE systems and later screened by their growth on a Malaysian crude oil. Selected strains of Pseudomonas sp. and Achromabacter sp. were then exposed individually to a similar crude oil in a mineralization unit and monitored for 16 days for release of CO{sub 2}. Pseudomonas paucimobilis was found to produce more CO{sub 2} than Achromobacter sp. When tested under similar conditions, mixed populations of these two taxa produced more CO{sub 2} than that produced by any individual strain. Effective bioremediation of local crude in Malaysian waters can therefore be achieved from biochemically developed Pseudomonas sp. strains.

  13. Properties of Polyhydroxyalkanoate Granules and Bioemulsifiers from Pseudomonas sp. and Burkholderia sp. Isolates Growing on Glucose.

    Science.gov (United States)

    Sacco, Laís Postai; Castellane, Tereza Cristina Luque; Lopes, Erica Mendes; de Macedo Lemos, Eliana Gertrudes; Alves, Lúcia Maria Carareto

    2016-03-01

    A Burkholderia and Pseudomonas species designated as AB4 and AS1, respectively, were isolated from soil containing decomposing straw or sugar cane bagasse collected from Brazil. This study sought to evaluate the capacities of culture media, cell-free medium, and crude lysate preparations (containing PHB inclusion bodies) from bacterial cell cultures to stabilize emulsions with several hydrophobic compounds. Four conditions showed good production of bioemulsifiers (E24 ≥ 50 %), headed by substantially cell-free media from bacterial cell cultures in which bacterial isolates from Burkholderia sp. strain AB4 and Pseudomonas sp. strain AS1 were grown. Our results revealed that the both isolates (AB4 and AS1 strains) exhibited high emulsification indices (indicating usefulness in bioremediation) and good stabilities.

  14. Pseudomonas salegens sp. nov., a halophilic member of the genus Pseudomonas isolated from a wetland.

    Science.gov (United States)

    Amoozegar, Mohammad Ali; Shahinpei, Azadeh; Sepahy, Abbas Akhavan; Makhdoumi-Kakhki, Ali; Seyedmahdi, Shima Sadat; Schumann, Peter; Ventosa, Antonio

    2014-10-01

    A novel Gram-stain-negative, aerobic, non-endospore-forming, non-pigmented, rod-shaped, slightly halophilic bacterium, designated GBPy5(T), was isolated from aquatic plants of the Gomishan wetland, Iran. Cells of strain GBPy5(T) were motile. Growth occurred with between 1 and 10% (w/v) NaCl and the isolate grew optimally with 3% (w/v) NaCl. The optimum pH and temperature for growth of the strain were pH 8.0 and 30 °C, respectively, while it was able to grow over a pH range of 6.5-9.0 and a temperature range of 4-35 °C. Phylogenetic analysis, based on 16S rRNA gene sequences, revealed that strain GBPy5(T) is a member of the genus Pseudomonas forming a monophyletic branch. The novel strain exhibited 16S rRNA gene sequence similarity of 95.4% with type strains of Pseudomonas guariconensis PCAVU11(T) and Pseudomonas sabulinigri J64(T), respectively. The major cellular fatty acids of the isolate were C18:1ω7c (37.8%), C16:0 (14.9%), C16:1ω7c (12.9%), C12:0 3-OH (7.1%) and C12:0 (7.0%). The polar lipid pattern of strain GBPy5(T) comprised phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine and one phospholipid. Ubiquinone 9 (Q-9) was the predominant lipoquinone. The G+C content of the genomic DNA of strain GBPy5(T) was 59.2 mol%. On the basis of the phenotypic and phylogenetic data, strain GBPY5(T) represents a novel species of the genus Pseudomonas, for which the name Pseudomonas salegens sp. nov. is proposed. The type strain is GBPy5(T) ( = IBRC-M 10762(T) = CECT 8338(T)).

  15. Pseudomonas salina sp. nov., isolated from a salt lake.

    Science.gov (United States)

    Zhong, Zhi-Ping; Liu, Ying; Hou, Ting-Ting; Liu, Hong-Can; Zhou, Yu-Guang; Wang, Fang; Liu, Zhi-Pei

    2015-09-01

    A Gram-staining-negative, facultatively aerobic bacterium, strain XCD-X85(T), was isolated from Xiaochaidan Lake, a salt lake (salinity 9.9%, w/v) in Qaidam basin, Qinghai province, China. Its taxonomic position was determined by using a polyphasic approach. Cells of strain XCD-X85(T) were non-endospore-forming rods, 0.4-0.6 μm wide and 1.0-1.6 μm long, and motile by means of a single polar flagellum. Strain XCD-X85(T) was catalase- and oxidase-positive. Growth was observed in the presence of 0-12.0% (w/v) NaCl (optimum, 1.0-2.0%) and at 4-35 °C (optimum, 25-30 °C) and pH 6.5-10.5 (optimum, pH 8.0-8.5). Strain XCD-X85(T) contained (>10%) summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), C12 : 0, C16 : 0 and summed feature 3 (C16 : 1ω7c and/or C16 : 1ω6c) as the predominant fatty acids. The major respiratory quinone was ubiquinone 9 (Q-9). The major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. The DNA G+C content was 57.4 mol%. Phylogenetic trees based on 16S rRNA gene sequences showed that strain XCD-X85(T) was associated with the genus Pseudomonas, and showed highest 16S rRNA gene sequence similarities to Pseudomonas pelagia CL-AP6(T) (99.0%) and Pseudomonas bauzanensis BZ93(T) (96.8%). DNA-DNA relatedness of strain XCD-X85T to P. pelagia JCM 15562(T) was 19 ± 1%. On the basis of the data presented above, it is concluded that strain XCD-X85(T) represents a novel species of the genus Pseudomonas, for which the name Pseudomonas salina sp. nov. is proposed. The type strain is XCD-X85(T) ( = CGMCC 1.12482(T) = JCM 19469(T)).

  16. Biodegradation of hexavalent chromium (Cr+6) in wastewater using Pseudomonas sp. and Bacillus sp. bacterial strains

    Energy Technology Data Exchange (ETDEWEB)

    Qasim, Muhammad [Department of Chemical Engineering, American University of Sharjah (United Arab Emirates)

    2013-07-01

    The recovery of toxic metal compounds is a deep concern in all industries. Hexavalent chromium is particularly worrying because of its toxic influence on human health. In this paper, biodegradation of hexavalent chromium (Cr+6) present in wastewater has been studied using two different bacterial strains; Pseudomonas sp. and Bacillus sp. A chemostat (with and without recycle of cells) with 10 L liquid culture volume was used to study the substrate and the biomass cell concentrations with time. Also, the degree of substrate conversion was studied by the varying the dilution rate as an independent parameter. The dilution rate (ratio of feed flow rate to the culture volume) was varied by varying the feed volumetric rate from 110-170 mL/h for inlet hexavalent chromium concentrations of 70 mg/dm3. The results show that a chemostat with recycle gives a better performance in terms of substrate conversion than a chemostat without a recycle. Moreover, the degree of substrate conversion decreases as the dilution rate is increased. Also, Bacillus sp. was found to give higher conversions compared to pseudomonas sp.

  17. Crystallographic Studies of Cephalosporin Acylase from Pseudomonas sp. Strain 130

    Institute of Scientific and Technical Information of China (English)

    DING Yi(丁怡); JIANG Weihong(姜卫红); ZHANG Shuping(张淑平); MAO Xiang(茅翔); Mark Bartlam; ZHAO Guoping(赵国平); RAO Zihe(饶子和)

    2003-01-01

    The cephalosporin acylases are a group of enzymes that hydrolyze cephalosporin C and/or glutaryl 7-aminocephalosporanic acid to produce 7-aminocephalosporanic acid.The cephalosporin acylase from Pseudomonas sp.strain 130 was crystallized in two different forms suitable for structural studies.A tetragonal crystal form diffracted to 0.24 nm belonged to the space group P41212.There was one αβ heterodimer per asymmetric unit.A second crystal form diffracted to 0.21 nm belonged to the space group P21.There was four αβ heterodimers per asymmetric unit.The tetragonal crystal structure of CA-130 was determined using the multiwavelength anomalous diffraction method and the P21 crystal structure was then determined using the molecular replacement method.

  18. Anthranilate degradation by a cold-adapted Pseudomonas sp.

    Science.gov (United States)

    Kim, Dockyu; Yoo, Miyoun; Kim, Eungbin; Hong, Soon Gyu

    2015-03-01

    An alpine soil bacterium Pseudomonas sp. strain PAMC 25931 was characterized as eurypsychrophilic (both psychrophilic and mesotolerant) with a broad temperature range of 5-30 °C both for anthranilate (2-aminobenzoate) degradation and concomitant cell growth. Two degradative gene clusters (antABC and catBCA) were detected from a fosmid clone in the PAMC 25931 genomic library; each cluster was confirmed to be specifically induced by anthranilate. When expressed in Escherichia coli, the recombinant AntABC (anthranilate 1,2-dioxygenase, AntDO) converted anthranilate into catechol, exhibiting strict specificity toward anthranilate. Recombinant CatA (catechol 1,2-dioxygenase, C12O) from the organism was active over a broad temperature range (5-37 °C). However, CatA rapidly lost the enzyme activity when incubated at above 25 °C. For example, 1 h-preincubation at 37 °C resulted in 100% loss of enzyme activity, while a counterpart from mesophilic Pseudomonas putida mt-2 did not show any negative effect on the initial enzyme activity. These results suggest that CatA is a new cold-adapted thermolabile enzyme, which might be a product through the adaptation process of PAMC 25931 to naturally cold environments and contribute to its ability to grow on anthranilate there.

  19. Pseudomonas hussainii sp. nov., isolated from droppings of a seashore bird, and emended descriptions of Pseudomonas pohangensis, Pseudomonas benzenivorans and Pseudomonas segetis.

    Science.gov (United States)

    Hameed, Asif; Shahina, Mariyam; Lin, Shih-Yao; Liu, You-Cheng; Young, Chiu-Chung

    2014-07-01

    Two Gram-staining-negative, aerobic, rod-shaped, non-spore-forming bacterial strains that are motile by a monopolar flagellum, designated CC-AMH-11(T) and CC-AMHZ-5, were isolated from droppings of a seashore bird off the coast of Hualien, Taiwan. The strains showed 99.7% mutual pairwise 16S rRNA gene sequence similarity, while exhibiting Pseudomonas (95.7-95.9% similarity with type species, Pseudomonas aeruginosa LMG 1242T), and formed a distinct co-phyletic lineage in the phylogenetic trees. The common major fatty acids (>5% of the total) were C18 : 1ω7c and/or C18 : 1ω6c (summed feature 8), C16 : 1ω6c and/or C16 : 1ω7c (summed feature 3), C16 : 0 and C12 : 0. Phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, phosphatidylserine, an unidentified lipid and an unidentified phospholipid were detected as common polar lipids. The DNA G+C contents of strains CC-AMH-11(T) and CC-AMHZ-5 were 61.1 and 61.6 mol%, respectively. The common major respiratory quinone was ubiquinone 9 (Q-9), and the predominant polyamine was putrescine. The DNA-DNA hybridization obtained between the two strains was 79.0% (reciprocal value 89.4% using CC-AMHZ-5 DNA as the probe). The very high 16S rRNA gene sequence similarity and DNA-DNA relatedness and the poorly distinguishable phenotypic features witnessed between CC-AMH-11(T) and CC-AMHZ-5 suggested unambiguously that they are two distinct strains of a single genomic species. However, the strains also showed several genotypic and phenotypic characteristics that distinguished them from other closely related species of Pseudomonas. Thus, the strains are proposed to represent a novel species of Pseudomonas, for which the name Pseudomonas hussainii sp. nov. is proposed. The type strain is CC-AMH-11(T) ( = JCM 19513(T) = BCRC 80696(T)); a second strain of the same species is CC-AMHZ-5 ( = JCM 19512 = BCRC 80697). In addition, emended descriptions of the species Pseudomonas pohangensis, Pseudomonas benzenivorans and

  20. Kinetics of p-cresol degradation by an immobilized Pseudomonas sp.

    OpenAIRE

    O'Reilly, K T; Crawford, R L

    1989-01-01

    A p-cresol (PCR)-degrading Pseudomonas sp. was isolated from creosote-contaminated soil and shown to degrade PCR by conversion to protocatechuate via p-hydroxybenzaldehyde (PBA) and p-hydroxybenzoate (PHB). Cells of the Pseudomonas sp. were immobilized in calcium alginate beads and in polyurethane foam. The relationship between the PCR concentration and the PCR transformation rate was investigated in batch and continuous culture bioreactors. The biodegradation kinetics of PBA and PHB also wer...

  1. Bioremediation potential of five strains of Pseudomonas sp.

    Directory of Open Access Journals (Sweden)

    Stamenov Dragana R.

    2015-01-01

    Full Text Available Because of their huge biodiversity and metabolic capabilities, the application of microorganisms as bioremediation agents is a way to enhance pollutant degradation. The aim of this research was to investigate the potential of five strains of Pseudomonas sp. as possible bioremediation agents. Strains are from the Collection of the Microbiology Department, Faculty of Agriculture, Novi Sad. Bacterial strains were cultivated in King’s B liquid medium and incubated in shak­er at 28°C. Starter culture was obtained after 24h, CFU 108. This 24h old bacterial culture was used for the analysis of influence of five different natural naphthenic acids. Bacterial growth was determined spectrophotometrically through optical density, after 24h and 48h of growth. Our results showed that two bacterial strains (PS V1 and PS2 had better growth after 48h as they used C from the petroleum derivates. The growth of these strains was increased by 72% and 25% with deri­vates concentration of 10-5 mol/cm3 and 10-6 mol/cm3, respectively. The results of this research showed the potential of certain bacterial strains as bioremediators. [Projekat Ministarstva nauke Republike Srbije, br. TD 31027 i br. III 043002

  2. Interaction between fish spoilage bacteria Pseudomonas sp and Shewanella putrefaciens in fish extracts and on fish tissue

    DEFF Research Database (Denmark)

    Gram, Lone; Melchiorsen, Jette

    1996-01-01

    The interaction between fish spoilage bacteria, Pseudomonas sp. and Shewanella putrefaciens, was investigated using fish extract and fish tissue as model systems. Isolates of Pseudomonas that produced iron chelators, siderophores, inhibited growth of S. putrefaciens in a fish-extract-agar diffusion...... assay but no, or only weak, antagonistic activity was seen when the medium was supplemented with iran. Sterile- filtered supernatant fluid from a siderophore-producing Pseudomonas grown in fish extract was inhibitory to S. putrefaciens if the number of Pseudomonas was above 10(8) cfu ml(-1). In contrast......, supernatant fluids from siderophore- negative Pseudomonas isolates did not inhibit growth of S. putrefaciens. The inhibitory effect was, except for one strain of Pseudomonas, not seen in supernatant fluids from iron- enriched cultures of Pseudomonas sp. Finally, siderophore- producing Pseudomonas sp. lowered...

  3. Comparative studies on crosslinked and uncrosslinked natural rubber biodegradation by Pseudomonas sp.

    Science.gov (United States)

    Roy, Ram Vinod; Das, Mithu; Banerjee, Rintu; Bhowmick, Anil K

    2006-12-01

    A comparative study on biodegradation of di-cumyl peroxide (DCP) crosslinked and uncrosslinked natural rubber by Pseudomonas sp. was carried out. Decrease in organic carbon content along with the changes in tensile strength of the treated rubber, both DCP crosslinked and uncrosslinked natural rubber, indicated rubber hydrocarbon utilization by the Pseudomonas sp. A decrease in 60.88% MPa and 41.66% MPa was observed after five month's old treated uncrosslinked natural rubber and DCP crosslinked rubber, respectively. Biodegradation was more pronounced in natural uncrosslinked rubber, which was further confirmed by the formation of aldehydic compounds with decrease in CH2 stretching frequencies.

  4. Selection of Pseudomonas sp. strain HBP1 Prp for metabolism of 2-propylphenol and elucidation of the degradative pathway

    NARCIS (Netherlands)

    Kohler, Hans-Peter E.; Maarel, Marc J.E.C. van der; Kohler-Staub, Doris

    1993-01-01

    A mutant of Pseudomonas sp. strain HBP1, originally isolated on 2-hydroxybiphenyl, was selected for the ability to grow on 2-propylphenol as the sole carbon and energy source. In the mutant strain, which was designated as Pseudomonas sp. strain HBP1 Prp, the cellular induction mechanism involved in

  5. Pseudomonas hunanensis sp. nov., isolated from soil subjected to long-term manganese pollution.

    Science.gov (United States)

    Gao, Jian; Li, Bai-Yuan; Wang, Hai-Hua; Liu, Zhi-Qiang

    2014-07-01

    A Gram-negative, polar flagella, rod-shaped bacterium LV (T) was isolated from a soil sample subjected to long-term manganese pollution in Hunan Province, China. Cells grow optimally on Luria-Bertani agar medium at 30 °C in the presence of 0-5.0 % (w/v) NaCl and pH 7-8. 16S rRNA gene sequence analysis revealed that strain LV (T) belonged to the genus Pseudomonas, with sequence similarity values of 98.6, 98.2, 98.7, and 97.3 % to Pseudomonas monteilii BCRC 17520 (T) , Pseudomonas putida BCRC 10459 (T) , Pseudomonas plecoglossicida BCRC 17517 (T) , and Pseudomonas asplenii BCRC 17131 (T) , respectively. The level of DNA-DNA relatedness between the five strains was Pseudomonas. Thus, strain LV (T) represents a novel species of the genus Pseudomonas, for which the name Pseudomonas hunanensis sp. nov. is proposed. The type strain is LV (T) (=CICC 10558(T) = NCCB 100446(T)).

  6. DEGRADATION OF 2-CHLOROALLYLALCOHOL BY A PSEUDOMONAS SP

    NARCIS (Netherlands)

    Waarde, Jaap J. van der; Kok, Rixt; Janssen, Dick B.

    Three Pseudomonas strains capable of utilizing 2-chloroallylalcohol (2-chloropropenol) as the sole carbon source for growth were isolated from soil. The fastest growth was observed with strain JD2, with a generation time of 3.6 h. Degradation of 2-chloroallylalcohol was accompanied by complete

  7. Conversion of p-nitrophenol to 4-nitrocatechol by a Pseudomonas sp.

    Science.gov (United States)

    Sudhakar-Barik; Siddaramappa, R; Wahid, P A; Sethunathan, N

    1978-01-01

    A strain of Pseudomonas sp. ATCC 29354, isolated from parathionamended flooded soil, converted p-nitrophenol to 4-nitrocatechol which persisted in pure culture. In unsterilized flooded soil, not previously treated with parathion, 4-nitrocatechol was further metabolized by other microorganisms.

  8. Degradation of 4-chloro-3-nitrophenol via a novel intermediate, 4-chlororesorcinol by Pseudomonas sp. JHN

    Science.gov (United States)

    Arora, Pankaj Kumar; Srivastava, Alok; Singh, Vijay Pal

    2014-03-01

    A 4-chloro-3-nitrophenol (4C3NP)-mineralizing bacterium, Pseudomonas sp. JHN was isolated from a waste water sample collected from a chemically-contaminated area, India by an enrichment method. Pseudomonas sp. JHN utilized 4C3NP as a sole carbon and energy source and degraded it with the release of stoichiometric amounts of chloride and nitrite ions. Gas chromatography and gas chromatography-mass spectrometry detected 4-chlororesorcinol as a major metabolite of the 4C3NP degradation pathway. Inhibition studies using 2,2'-dipyridyl showed that 4-chlororesorcinol is a terminal aromatic compound in the degradation pathway of 4C3NP. The activity for 4C3NP-monooxygenase was detected in the crude extracts of the 4C3NP-induced JHN cells that confirmed the formation of 4-chlororesorcinol from 4C3NP. The capillary assay showed that Pseudomonas sp. JHN exhibited chemotaxis toward 4C3NP. The bioremediation capability of Pseudomonas sp. JHN was monitored to carry out the microcosm experiments using sterile and non-sterile soils spiked with 4C3NP. Strain JHN degraded 4C3NP in sterile and non-sterile soil with same degradation rates. This is the first report of (i) bacterial degradation and bioremediation of 4C3NP, (ii) formation of 4-chlororesorcinol in the degradation pathway of 4C3NP, (iii) bacterial chemotaxis toward 4C3NP.

  9. Effect of Catalase on Biocatalytic Synthesis of Pyruvate by Enzymes from Pseudomonas sp.

    Institute of Scientific and Technical Information of China (English)

    Jing Song GU; Yuan Xiu WANG; Qiang JIAO

    2004-01-01

    Pyruvate was produced from DL-lactate by a kind of green-chemical biocatalyst - cell-free extract from bacterial strain Pseudomonas sp. SM-6. Catalase in cell-free extract, which could stabilize the pyruvate formed by lactate oxidase, played an important role in pyruvate preparation. The effect of catalase in conversion process was evaluated.

  10. OXIDATION OF BIPHENYL BY A MULTICOMPONENT ENZYME SYSTEM FROM PSEUDOMONAS SP. STRAIN LB400

    Science.gov (United States)

    Pseudomonas sp. strain LB400 grows on biphenyl as the sole carbon and energy source. This organism also cooxidizes several chlorinated biphenyl congeners. Biphenyl dioxygenase activity in cell extract required addition of NAD(P)H as an electron donor for the conversion of bipheny...

  11. Biocatalytic synthesis of pyruvate from DL-lactate with enzymes in Pseudomonas sp

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A novel method of preparing pyruvate from DL-lactate catalyzed by enzymes from a bacterial strain of Pseudomonas sp. SM-6 was proposed. Catalytic processes of cell-free extract enzymes and immobilized enzymes were evaluated. The kinetic data were studied, too.

  12. Distribution and survival of Pseudomonas sp. on Italian ryegrass and Curly dock in Georgia

    Science.gov (United States)

    Yellow bud, caused by Pseudomonas sp. is an emerging bacterial disease of onion. Polymerase chain reaction (PCR) assay based on the coronafacate ligase (cfl) and HrpZ genes were used to detect initial suspected bacteria on weeds. Growth on an agar medium, ability to cause a hypersensitive response i...

  13. Pseudomonas frederiksbergensis sp. nov., isolated from soil at a coal gasification site.

    Science.gov (United States)

    Andersen, S M; Johnsen, K; Sørensen, J; Nielsen, P; Jacobsen, C S

    2000-11-01

    Phenotypic and genotypic characterization indicated that a group of 29 closely related phenanthrene-degrading bacteria from a coal gasification site in Frederiksberg, Copenhagen, Denmark, belonged to the genus Pseudomonas. The strains were isolated at two sampling occasions 2 years apart. The isolates were phenotypically different from any known species of the genus Pseudomonas and were therefore subject to further identification. Colonies were smooth and pale yellowish and did not produce pigments fluorescent in UV light when grown on King's B agar. Cells were rod-shaped, approximately 0.5-0.8 x 1.5-3.0 microm, and grew at 4 and 30 degrees C, but not 37 degrees C. The bacteria were oxidase- and catalase-positive, accumulated poly-beta-hydroxybutyrate and denitrified, but did not utilize D-xylose. The mean G+C content was 59.6 mol%. Phenotypic data and 16S rDNA sequence data information for Pseudomonas amygdali and Pseudomonas corrugata, and 16S rDNA sequence data for Pseudomonas chlororaphis and Pseudomonas syringae showed close relationships to these strains. However, DNA-DNA hybridization data showed that the isolates belong to a new species, for which the name Pseudomonas frederiksbergensis sp. nov. is proposed. The type strain is JAJ28T (DSM 13022T).

  14. Analysis of Diversity of Pyridine Degradation by Three Pseudomonas sp.%三株Pseudomonas sp.的吡啶降解多样性分析

    Institute of Scientific and Technical Information of China (English)

    易霞; 韦良焕

    2011-01-01

    目的:为了探讨3株Pseudomonas sp.对吡啶降解存在多样性.方法:基于16S rRNA和ISR序列分析,对3株分离菌株进行初步鉴定,进而通过Touch -Down PCR,对3株细菌降解吡啶的多样性进行分析.结果:3株细菌XJUHX -1、XJUHX - 12和XJUHX - 16初步鉴定为Pseudomonas,3株实验菌株的部分降解基因的扩增条带有差异.结论:同属的3株 Pseudomonas在吡啶降解上存在多样性.

  15. Pseudomonas kribbensis sp. nov., isolated from garden soils in Daejeon, Korea.

    Science.gov (United States)

    Chang, Dong-Ho; Rhee, Moon-Soo; Kim, Ji-Sun; Lee, Yookyung; Park, Mi Young; Kim, Haseong; Lee, Seung-Goo; Kim, Byoung-Chan

    2016-11-01

    Two bacterial strains, 46-1 and 46-2(T), were isolated from garden soil. These strains were observed to be aerobic, Gram-stain negative, rod-shaped, non-spore-forming, motile and catalase and oxidase positive. Phylogenetic analysis based on 16S rRNA gene sequences showed that the two strains shared 100 % sequence similarity with each other and belong to the genus Pseudomonas in the class Gammaproteobacteria. The concatenated 16S rRNA, gyrB, rpoB and rpoD gene sequences further confirmed that the isolates belong to the Pseudomonas koreensis subgroup (SG), with P. koreensis Ps 9-14(T), Pseudomonas moraviensis 1B4(T) and Pseudomonas granadensis F-278,770(T) as their close relatives (>96 % pairwise similarity). DNA-DNA hybridization with the closely related type strain P. koreensis SG revealed a low level of relatedness (15 %) in the isolates but it was a minor component (Pseudomonas, for which the name Pseudomonas kribbensis sp. nov. is proposed; the type strain is 46-2(T) (=KCTC 32541(T) = DSM 100278(T)).

  16. Interaction between fish spoilage bacteria Pseudomonas sp and Shewanella putrefaciens in fish extracts and on fish tissue

    DEFF Research Database (Denmark)

    Gram, Lone; Melchiorsen, Jette

    1996-01-01

    The interaction between fish spoilage bacteria, Pseudomonas sp. and Shewanella putrefaciens, was investigated using fish extract and fish tissue as model systems. Isolates of Pseudomonas that produced iron chelators, siderophores, inhibited growth of S. putrefaciens in a fish-extract-agar diffusion...

  17. Isolation and identification of antifungal N-butylbenzenesulphonamide produced by Pseudomonas sp. AB2.

    Science.gov (United States)

    Kim, K K; Kang, J G; Moon, S S; Kang, K Y

    2000-02-01

    An antifungal bacterial strain, isolated from a greenhouse soil sample, inhibits growth of microflora nearby. It was selected for further studies of bacterial antifungal properties. This isolate was identified as a Pseudomonas sp. based on carbohydrate utilization, and other biochemical and physiological tests. Petri plate assay revealed that the Pseudomonas sp. exhibited antifungal activity against the plant pathogens, Pythium ultimum, Rhizoctonia solani, Phytophthora capsici, Botrytis cinerea and Fusarium oxysporum. Using direct inhibition bioassay on TLC plates after ethyl acetate extraction of the culture filtrate, we correlated antifungal activity with production of antifungal compounds. An antifungal antibiotic was isolated from the culture filtrate and was identified as N-butylbenzenesulphonamide. ED50, values of the N-butylbenzenesulphonamide against P. ultimum, P. capsici, R. solani, and B. cinerea were 73, 41, 33 and 102 ppm, respectively.

  18. Biodegradation and detoxification of reactive textile dye by isolated Pseudomonas sp. SUK1.

    Science.gov (United States)

    Kalyani, Dayanad C; Telke, Amar A; Govindwar, Sanjay P; Jadhav, Jyoti P

    2009-03-01

    An isolated bacterium from a textile disposal site, Pseudomonas sp. SUK1, has the ability to decolorize the reactive textile dyes and methyl orange. This bacterium showed the potential to decolorize the textile dye Reactive Blue 59 at a high concentration (5 g/L(-1)), which is frequently used in the textile industry of Solapur, India. Induction in the activities of lignin peroxidase, azoreductase, and dichlorophenol indophenol reductase was observed during the decolorization of Methyl Orange and Reactive Blue 59. Methyl Orange (as model azo dye) was used to understand the mechanism of biodegradation by Pseudomonas sp. SUK1. The final product was identified as 1,4-benzenediamine, N, N-dimethyl by gas chromatography-mass spectroscopy. Microbial and phytotoxicity studies revealed the nontoxic nature of the products of Reactive Blue 59.

  19. Bioactivities by a crude extract from the Greenlandic Pseudomonas sp. In5 involves the nonribosomal peptides, nunamycin and nunapeptin

    DEFF Research Database (Denmark)

    Frydenlund Michelsen, Charlotte; Jensen, Helle; Venditto, Vincent J.;

    2015-01-01

    Bioactive microbial metabolites provide a successful source of novel compounds with pharmaceutical potentials. The bacterium Pseudomonas sp. In5 is a biocontrol strain isolated from a plant disease suppressive soil in Greenland, which produces two antimicrobial nonribosomal peptides (NRPs......), nunapeptin and nunamycin. In this study, we used in vitro antimicrobial and anticancer bioassays to evaluate the potential bioactivities of both a crude extract derived from Pseudomonas sp. In5 and NRPs purified from the crude extract....

  20. Degradation and metabolism of synthetic plastics and associated products by Pseudomonas sp.: capabilities and challenges.

    Science.gov (United States)

    Wilkes, R A; Aristilde, L

    2017-09-01

    Synthetic plastics, which are widely present in materials of everyday use, are ubiquitous and slowly-degrading polymers in environmental wastes. Of special interest are the capabilities of microorganisms to accelerate their degradation. Members of the metabolically diverse genus Pseudomonas are of particular interest due to their capabilities to degrade and metabolize synthetic plastics. Pseudomonas species isolated from environmental matrices have been identified to degrade polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyurethane, polyethylene terephthalate, polyethylene succinate, polyethylene glycol and polyvinyl alcohol at varying degrees of efficiency. Here, we present a review of the current knowledge on the factors that control the ability of Pseudomonas sp. to process these different plastic polymers and their by-products. These factors include cell surface attachment within biofilms, catalytic enzymes involved in oxidation or hydrolysis of the plastic polymer, metabolic pathways responsible for uptake and assimilation of plastic fragments and chemical factors that are advantageous or inhibitory to the biodegradation process. We also highlight future research directions required in order to harness fully the capabilities of Pseudomonas sp. in bioremediation strategies towards eliminating plastic wastes. © 2017 The Society for Applied Microbiology.

  1. Plasmid-mediated Detoxification of Mycotoxin Zearalenone in Pseudomonas Sp. ZEA-1

    OpenAIRE

    2007-01-01

    The Pseudomonas sp. Strain ZEA-1 was isolated from rhizosphere of corn plant by an enrichment technique showed capability of utilizing zearalenone as the sole source of carbon. The bacterium rapidly utilized zearalenone beyond 200 µg/ml and showed prolific growth in a minimal medium containing 100 µg/ml zearalenone source. The course of ZEA degradation as well as the formation of its metabolites was observed by UV Spectrophotometer and thin layer chromatography analysis. Toxicity of biotransf...

  2. Kinetics of p-cresol degradation by an immobilized Pseudomonas sp.

    Science.gov (United States)

    O'Reilly, K T; Crawford, R L

    1989-04-01

    A p-cresol (PCR)-degrading Pseudomonas sp. was isolated from creosote-contaminated soil and shown to degrade PCR by conversion to protocatechuate via p-hydroxybenzaldehyde (PBA) and p-hydroxybenzoate (PHB). Cells of the Pseudomonas sp. were immobilized in calcium alginate beads and in polyurethane foam. The relationship between the PCR concentration and the PCR transformation rate was investigated in batch and continuous culture bioreactors. The biodegradation kinetics of PBA and PHB also were investigated. In batch culture reactors, the maximum PCR degradation rate (Vmax) for the alginate-immobilized Pseudomonas sp. cells was 1.5 mg of PCR g of bead-1 h-1 while the saturation constant (Ks) was 0.22 mM. For PHB degradation, the Vmax was 0.62 mg of PHB g of bead-1 h-1 while the Ks was 0.31 mM. For polyurethane-immobilized Pseudomonas sp. cells, the Vmax of PCR degradation was 0.80 mg of PCR g of foam-1 h-1 while the Ks was 0.28 mM. For PHB degradation, the Vmax was 0.21 mg of PHB g of foam-1 h-1 and the Ks was 0.22 mM. In a continuous column alginate bead reactor, the Vmax for PCR transformation was 2.6 mg g of bead-1 h-1 while the Ks was 0.20 mM. The Vmax and Ks for PBA transformation in the presence of PCR were 0.93 mg g of bead-1 h-1 and 0.063 mM, respectively. When PHB alone was added to a reactor, the Vmax was 1.48 mg g of bead-1 h-1 and the Ks was 0.32 mM.(ABSTRACT TRUNCATED AT 250 WORDS)

  3. Kinetics of growth and caffeine demethylase production of Pseudomonas sp. in bioreactor.

    Science.gov (United States)

    Gummadi, Sathyanarayana N; Santhosh, Devarai

    2010-09-01

    The effect of various initial caffeine concentrations on growth and caffeine demethylase production by Pseudomonas sp. was studied in bioreactor. At initial concentration of 6.5 g l(-1) caffeine, Pseudomonas sp. showed a maximum specific growth rate of 0.2 h(-1), maximum degradation rate of 1.1 g h(-1), and caffeine demethylase activity of 18,762 U g CDW(-1) (CDW: cell dry weight). Caffeine degradation rate was 25 times higher in bioreactor than in shake flask. For the first time, we show highest degradation of 75 g caffeine (initial concentration 20 g l(-1)) in 120 h, suggesting that the tested strain has potential for successful bioprocess for caffeine degradation. Growth kinetics showed substrate inhibition phenomenon. Various substrate inhibition models were fitted to the kinetic data, amongst which the double-exponential (R(2) = 0.94), Luong (R(2) = 0.92), and Yano and Koga 2 (R(2) = 0.94) models were found to be the best. The Luedeking-Piret model showed that caffeine demethylase production kinetics was growth related. This is the first report on production of high levels of caffeine demethylase in batch bioreactor with faster degradation rate and high tolerance to caffeine, hence clearly suggesting that Pseudomonas sp. used in this study is a potential biocatalyst for industrial decaffeination.

  4. Biodegradation of Methyl tert-Butyl Ether by Co-Metabolism with a Pseudomonas sp. Strain

    Directory of Open Access Journals (Sweden)

    Shanshan Li

    2016-09-01

    Full Text Available Co-metabolic bioremediation is supposed to be an impressive and promising approach in the elimination technology of methyl tert-butyl ether (MTBE, which was found to be a common pollutant worldwide in the ground or underground water in recent years. In this paper, bacterial strain DZ13 (which can co-metabolically degrade MTBE was isolated and named as Pseudomonas sp. DZ13 based on the result of 16S rRNA gene sequencing analysis. Strain DZ13 could grow on n-alkanes (C5-C8, accompanied with the co-metabolic degradation of MTBE. Diverse n-alkanes with different carbon number showed a significant influence on the degradation rate of MTBE and accumulation of tert-butyl alcohol (TBA. When Pseudomonas sp. DZ13 co-metabolically degraded MTBE with n-pentane as the growth substrate, a higher MTBE-degrading rate (Vmax = 38.1 nmol/min/mgprotein, Ks = 6.8 mmol/L and lower TBA-accumulation was observed. In the continuous degradation experiment, the removal efficiency of MTBE by Pseudomonas sp. Strain DZ13 did not show an obvious decrease after five times of continuous addition.

  5. Pseudomonas glareae sp. nov., a marine sediment-derived bacterium with antagonistic activity.

    Science.gov (United States)

    Romanenko, Lyudmila A; Tanaka, Naoto; Svetashev, Vassilii I; Mikhailov, Valery V

    2015-06-01

    An aerobic, Gram-negative, motile, rod-shaped bacterium designated KMM 9500(T) was isolated from a sediment sample collected from the Sea of Japan seashore. Comparative 16S rRNA gene sequence analysis affiliated strain KMM 9500(T) to the genus Pseudomonas as a distinct subline clustered with Pseudomonas marincola KMM 3042(T) and Pseudomonas segetis KCTC 12331(T) sharing the highest similarities of 98 and 97.9 %, respectively. Strain KMM 9500(T) was characterized by mainly possessing ubiquinone Q-9, and by the predominance of C18:1 ω7c, C16:1 ω7c, and C16:0 followed by C12:0 in its fatty acid profile. Polar lipids consisted of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, an unknown aminophospholipid, and unknown phospholipids. Strain KMM 9500(T) was found to inhibit growth of Gram-negative and Gram-positive indicatory microorganisms. Based on the phylogenetic analysis and distinctive phenotypic characteristics, strain 9500(T) is concluded to represent a novel species of the genus Pseudomonas, for which the name Pseudomonas glareae sp. nov. is proposed. The type strain of the species is strain KMM 9500(T) (=NRIC 0939(T)).

  6. Pseudomonas endophytica sp. nov., isolated from stem tissue of Solanum tuberosum L. in Spain.

    Science.gov (United States)

    Ramírez-Bahena, Martha-Helena; Cuesta, Maria José; Tejedor, Carmen; Igual, José Mariano; Fernández-Pascual, Mercedes; Peix, Álvaro

    2015-07-01

    A bacterial strain named BSTT44(T) was isolated in the course of a study of endophytic bacteria occurring in stems and roots of potato growing in a soil from Salamanca, Spain. The 16S rRNA gene sequence had 99.7% identity with respect to that of its closest relative, Pseudomonas psychrophila E-3T, and the next most closely related type strains were those of Pseudomonas fragi, with 99.6% similarity, Pseudomonas deceptionensis, with 99.2% similarity, and Pseudomonas lundensis, with 99.0% similarity; these results indicate that BSTT44(T) should be classified within the genus Pseudomonas. Analysis of the housekeeping genes rpoB, rpoD and gyrB confirmed its phylogenetic affiliation and showed identities lower than 92% in all cases with respect to the above-mentioned closest relatives. Cells of the strain bore one polar-subpolar flagellum. The respiratory quinone was Q-9.The major fatty acids were C16:0, C18:1ω7c and summed feature 3 (C16:1ω7c and/or C16:1ω6c). The strain was oxidase-, catalase- and urease-positive and the arginine dihydrolase system was present, but tests for nitrate reduction, β-galactosidase production and aesculin hydrolysis were negative. It could grow at 35 °C and at pH 5-9.The DNA G+C content was 60.2 mol%. DNA-DNA hybridization results showed less than 48% relatedness with respect to the type strains of the four most closely related species. Therefore, the combined results of genotypic, phenotypic and chemotaxonomic analyses support the classification of strain BSTT44 into a novel species of the genus Pseudomonas, for which the name Pseudomonas endophytica sp. nov. is proposed. The type strain is BSTT44(T) ( = LMG 28456(T) = CECT 8691(T)).

  7. Identification of microbial isolates from vacuum-packaged ground pork irradiated at 1 kGy. [Pseudomonas sp. ; Enterobacter sp

    Energy Technology Data Exchange (ETDEWEB)

    Ehioba, R.M.; Kraft, A.A.; Molins, R.A.; Walker, H.W.; Olson, D.G.; Subbaraman, G.; Skowronski, R.P.

    Bacterial cultures from irradiated (1 kGy) and nonirradiated, vacuum-packaged ground pork held at 5/sup 0/C were isolated and characterized over a 12-day storage period. The initial flora of the meat was composed mostly of Pseudomonas sp., and Enterobacter sp. Although the microflora of nonirradiated samples gradually shifted from Gram-negative to Gram-positive microorganisms, 76% of the isolates were characterized as Gram-negative at the onset of spoilage (9 days at 5/sup 0/C). In contrast, the irradiated ground pork microflora was mainly Gram-positive (66%) shortly after irradiation and increased to 97% after 9 days at 5/sup 0/C. A total of 720 isolates were identified to genus.

  8. The complete genome sequence of the plant growth-promoting bacterium Pseudomonas sp. UW4.

    Science.gov (United States)

    Duan, Jin; Jiang, Wei; Cheng, Zhenyu; Heikkila, John J; Glick, Bernard R

    2013-01-01

    The plant growth-promoting bacterium (PGPB) Pseudomonas sp. UW4, previously isolated from the rhizosphere of common reeds growing on the campus of the University of Waterloo, promotes plant growth in the presence of different environmental stresses, such as flooding, high concentrations of salt, cold, heavy metals, drought and phytopathogens. In this work, the genome sequence of UW4 was obtained by pyrosequencing and the gaps between the contigs were closed by directed PCR. The P. sp. UW4 genome contains a single circular chromosome that is 6,183,388 bp with a 60.05% G+C content. The bacterial genome contains 5,423 predicted protein-coding sequences that occupy 87.2% of the genome. Nineteen genomic islands (GIs) were predicted and thirty one complete putative insertion sequences were identified. Genes potentially involved in plant growth promotion such as indole-3-acetic acid (IAA) biosynthesis, trehalose production, siderophore production, acetoin synthesis, and phosphate solubilization were determined. Moreover, genes that contribute to the environmental fitness of UW4 were also observed including genes responsible for heavy metal resistance such as nickel, copper, cadmium, zinc, molybdate, cobalt, arsenate, and chromate. Whole-genome comparison with other completely sequenced Pseudomonas strains and phylogeny of four concatenated "housekeeping" genes (16S rRNA, gyrB, rpoB and rpoD) of 128 Pseudomonas strains revealed that UW4 belongs to the fluorescens group, jessenii subgroup.

  9. Genetic evidence of a high-affinity cyanuric acid transport system in Pseudomonas sp. ADP.

    Science.gov (United States)

    Platero, Ana I; Santero, Eduardo; Govantes, Fernando

    2014-03-01

    The Pseudomonas sp. ADP plasmid pADP-1 encodes the activities involved in the hydrolytic degradation of the s-triazine herbicide atrazine. Here, we explore the presence of a specific transport system for the central intermediate of the atrazine utilization pathway, cyanuric acid, in Pseudomonas sp. ADP. Growth in fed-batch cultures containing limiting cyanuric acid concentrations is consistent with high-affinity transport of this substrate. Acquisition of the ability to grow at low cyanuric acid concentrations upon conjugal transfer of pADP1 to the nondegrading host Pseudomonas putida KT2442 suggests that all activities required for this phenotype are encoded in this plasmid. Co-expression of the pADP1-borne atzDEF and atzTUVW genes, encoding the cyanuric acid utilization pathway and the subunits of an ABC-type solute transport system, in P. putida KT2442 was sufficient to promote growth at cyanuric acid concentrations as low as 50 μM in batch culture. Taken together, our results strongly suggest that the atzTUVW gene products are involved in high-affinity transport of cyanuric acid.

  10. The complete genome sequence of the plant growth-promoting bacterium Pseudomonas sp. UW4.

    Directory of Open Access Journals (Sweden)

    Jin Duan

    Full Text Available The plant growth-promoting bacterium (PGPB Pseudomonas sp. UW4, previously isolated from the rhizosphere of common reeds growing on the campus of the University of Waterloo, promotes plant growth in the presence of different environmental stresses, such as flooding, high concentrations of salt, cold, heavy metals, drought and phytopathogens. In this work, the genome sequence of UW4 was obtained by pyrosequencing and the gaps between the contigs were closed by directed PCR. The P. sp. UW4 genome contains a single circular chromosome that is 6,183,388 bp with a 60.05% G+C content. The bacterial genome contains 5,423 predicted protein-coding sequences that occupy 87.2% of the genome. Nineteen genomic islands (GIs were predicted and thirty one complete putative insertion sequences were identified. Genes potentially involved in plant growth promotion such as indole-3-acetic acid (IAA biosynthesis, trehalose production, siderophore production, acetoin synthesis, and phosphate solubilization were determined. Moreover, genes that contribute to the environmental fitness of UW4 were also observed including genes responsible for heavy metal resistance such as nickel, copper, cadmium, zinc, molybdate, cobalt, arsenate, and chromate. Whole-genome comparison with other completely sequenced Pseudomonas strains and phylogeny of four concatenated "housekeeping" genes (16S rRNA, gyrB, rpoB and rpoD of 128 Pseudomonas strains revealed that UW4 belongs to the fluorescens group, jessenii subgroup.

  11. Description of Pseudomonas gregormendelii sp. nov., a Novel Psychrotrophic Bacterium from James Ross Island, Antarctica.

    Science.gov (United States)

    Kosina, Marcel; Švec, Pavel; Černohlávková, Jitka; Barták, Miloš; Snopková, Kateřina; De Vos, Paul; Sedláček, Ivo

    2016-07-01

    During the microbiological research performed within the scope of activities of Czech expeditions based at the Johann Gregor Mendel Station at James Ross Island, Antarctica, two psychrotrophic gram-stain negative non-fluorescent strains CCM 8506T and CCM 8507 from soil were extensively characterized using genotypic and phenotypic methods. Initial characterization using ribotyping with HindIII restriction endonuclease and phenotyping implies that both isolates belong to a single Pseudomonas species. Sequencing of rrs, rpoB, rpoD and glnA genes of strain CCM 8506(T) confirmed affiliation of investigated strains within the genus Pseudomonas. Further investigation using automated ribotyping with EcoRI (RiboPrinter(®) Microbial Characterisation System), whole-cell protein profiling using the Agilent 2100 Bioanalyzer system, extensive biochemical testing and DNA-DNA hybridization experiments confirmed that both investigated strains are members of a single taxon which is clearly separated from all hitherto described Pseudomonas spp. Based on all findings, we describe a novel species Pseudomonas gregormendelii sp. nov. with the type strain CCM 8506(T) (=LMG 28632T).

  12. Conditions for Pseudomonas sp.W2 Culture and Bisphenol A Degradation%Pseudomonas sp.W2生长及对双酚A降解条件的研究

    Institute of Scientific and Technical Information of China (English)

    贾凌志; 李君文

    2007-01-01

    目的 研究双酚A(BPA)降解菌(Pseudomonas sp.W2)的生长及对BPA的降解条件,为今后环境中BPA污染的实际治理提供实验依据.方法 分别采用紫外扫描光谱分析和紫外光谱分析对Pseudomonas sp.W2菌株和BPA进行定量.分别绘制Pseudomonas sp.W2菌株的生长曲线及对BPA的降解曲线,并对其在不同的碳源、氮源、pH值、温度、通气情况下的生长情况及对BPA的降解情况进行分析.结果 在一定条件下(25~35℃,pH值为6-8,250 ml摇瓶中的培养基F装液量为50~100ml,有一定的碳源、氮源),Pseudomonas sp.W2的生长及对BPA降解作用较好.结论 Pseudomonas sp.W2菌株的生长及对BPA的降解的条件较宽,这对其在实际中的应用具有一定意义.

  13. Metabolism-independent chemotaxis of Pseudomonas sp.strain WBC-3 toward aromatic compounds

    Institute of Scientific and Technical Information of China (English)

    ZHANG Junjie; XIN Yufeng; LIU Hong; WANG Shujun; ZHOU Ningyi

    2008-01-01

    Pseudomonas sp. Strain WBC-3 utilized methyl parathion or para-nitrophenol (PNP) as the sole source of carbon, nitrogen, andenergy, and methyl parathion hydrolase had been previously characterized. Its chemotactic behaviors to aromatics were investigated.The results indicated that strain WBC-3 was attracted to multiple aromatic compounds, including metabolizable or transformablesubstrates PNP, 4-nitrocatehol, and hydroquinone. Disruption of PNP catabolic genes had no effect on its chemotactic behaviors with the same substrates, indicating that the chemotactic response in this swain was metabolism-independent. Furthermore, it was shownthat strain WBC-3 had a constitutive β-ketoadipate chemotaxis system that responded to a broad range of aromatic compounds, whichwas different from the inducible β-ketoadipate chemotaxis described in other Pseudomonas signs.

  14. Pseudomonas sp. BUP6, a novel isolate from Malabari goat produces an efficient rhamnolipid type biosurfactant.

    Science.gov (United States)

    Priji, Prakasan; Sajith, Sreedharan; Unni, Kizhakkepowathial Nair; Anderson, Robin C; Benjamin, Sailas

    2017-01-01

    This study describes the characteristics of a biosurfactant produced by Pseudomonas sp. BUP6, a rumen bacterium, and optimization of parameters required for its production. Initial screening of five parameters (pH, temperature, agitation, incubation, and substrate concentration) was carried out employing Plackett-Burman design, which reduced the number of parameters to 3 (pH, temperature, and incubation) according to their significance on the yield of biosurfactant. A suitable statistical model for the production of biosurfactant by Pseudomonas sp. BUP6 was established according to Box-Behnken design, which resulted in 11% increase (at pH 7, 35 °C, incubation 75 h) in the yield (2070 mg L(-1) ) of biosurfactant. The biosurfactant was found stable at a wide range of pH (3-9) with 48 mg L(-1) critical micelle concentration; and maintained over 90% of its emulsification ability even after boiling and in presence of sodium chloride (0.5%). The highest cell hydrophobicity (37%) and emulsification (69%) indices were determined with groundnut oil and kerosene, respectively. The biosurfactant was found to inhibit the growth and adhesion of E. coli and S. aureus significantly. From the phytotoxicity studies, the biosurfactant did not show any adverse effect on the germinating seeds of rice and green gram. The structural characterization of biosurfactant employing orcinol method, thin layer chromatography and FT-IR indicated that it is a rhamnolipid (glycolipid). Thus, Pseudomonas sp. BUP6, a novel isolate from Malabari goat is demonstrated as a producer of an efficient rhamnolipid type biosurfactant suitable for application in various industries.

  15. Arsenic redox transformation by Pseudomonas sp. HN-2 isolated from arsenic-contaminated soil in Hunan, China.

    Science.gov (United States)

    Zhang, Zhennan; Yin, Naiyi; Cai, Xiaolin; Wang, Zhenzhou; Cui, Yanshan

    2016-09-01

    A mesophilic, Gram-negative, arsenite[As(III)]-oxidizing and arsenate[As(V)]-reducing bacterial strain, Pseudomonas sp. HN-2, was isolated from an As-contaminated soil. Phylogenetic analysis based on 16S rRNA gene sequencing indicated that the strain was closely related to Pseudomonas stutzeri. Under aerobic conditions, this strain oxidized 92.0% (61.4μmol/L) of arsenite to arsenate within 3hr of incubation. Reduction of As(V) to As(III) occurred in anoxic conditions. Pseudomonas sp. HN-2 is among the first soil bacteria shown to be capable of both aerobic As(III) oxidation and anoxic As(V) reduction. The strain, as an efficient As(III) oxidizer and As(V) reducer in Pseudomonas, has the potential to impact arsenic mobility in both anoxic and aerobic environments, and has potential application in As remediation processes.

  16. Antimicrobial activities of Rhizobium sp. strains against Pseudomonas savastanoi, the agent responsible for the olive knot disease in Algeria

    Energy Technology Data Exchange (ETDEWEB)

    Mourad, K.; Fadhila, K.; Chahinez, M.; Merien, R.; Philippe, L. de; Abdelkader, B.

    2009-07-01

    In the present investigation, six Rhizobium strains isolated from Algerian soil were checked for their antimicrobial activity against Pseudomonas savastanoi, the agent responsible for olive knot disease. Rhizobium sp. ORN 24 and ORN 83 were found to produce antimicrobial activities against Pseudomonas savastanoi. The antimicrobial activity produced by Rhizobium sp. ORN24 was precipitable with ammonium sulfate, between 1,000 and 10,000 KDa molecular weight, heat resistant but sensitive to proteases and detergents. These characteristics suggest the bacteriocin nature of the antimicrobial substance produced by Rhizobium sp. ORN24, named rhizobiocin 24. In contrast, the antimicrobial activity produced by Rhizobium sp. ORN83 was not precipitable with ammonium sulfate; it was smaller than 1,000 KDa molecular weight, heat labile, and protease and detergent resistant. These characteristics could indicate the relationship between the antimicrobial substance produced by Rhizobium sp. ORN 83 and the small bacteriocins described in other rhizobia. (Author) 51 refs.

  17. Inhibition of food-related bacteria by antibacterial substances produced by Pseudomonas sp. strains isolated from pasteurized milk

    OpenAIRE

    Ana Beatriz Ferreira Rangel; Jean Thiago Alves Soares; Mariana Maciel Pereira; Bruna Rachel de Britto Peçanha; Leonardo Emanuel de Oliveira Costa; Janaína dos Santos Nascimento

    2013-01-01

    In this work, the production of antimicrobial substances by strains of Pseudomonas sp. isolated from pasteurized milk and their potential action against food-related bacteria were investigated. Samples of pasteurized milk were purchased from arbitrarily chosen commercial establishments in the city of Rio de Janeiro, Brazil. Of the four samples analyzed, three presented several typical colonies of Pseudomonas. About 100 colonies were chosen and subjected to biochemical tests for confirmation o...

  18. Pseudomonas extremaustralis sp. nov., a Poly(3-hydroxybutyrate) producer isolated from an antarctic environment.

    Science.gov (United States)

    López, Nancy I; Pettinari, M Julia; Stackebrandt, Erko; Tribelli, Paula M; Põtter, Markus; Steinbüchel, Alexander; Méndez, Beatriz S

    2009-11-01

    A Gram-negative, mobile, rod-shaped, non-spore-forming bacterium (strain 14-3(T)) was isolated from a temporary pond in Antarctica. On the basis of 16S rRNA gene sequence similarity, strain 14-3(T) was shown to belong to the genus Pseudomonas sensu stricto. Physiological and biochemical tests supported the phylogenetic affiliation. Strain 14-3(T) is closely related to Pseudomonas veronii DSM 11331(T), sharing 99.7% sequence similarity. DNA-DNA hybridization experiments between the two strains showed only moderate reassociation similarity (35.1%). Tests for arginine dihydrolase and nitrate reduction were positive, while those for denitrification, indol production, glucose acidification, urease, ss-galactosidase, esculin, caseine and gelatin hydrolysis were negative. Growth of this bacterium occurred in a range from 4 to 37 degrees C but not at 42 degrees C. It accumulated poly(3-hydroxybutyrate) when grown on sodium octanoate medium. Strain 14-3(T) therefore represents the type strain of a new species, for which the name Pseudomonas extremaustralis sp. nov. is proposed. The type strain 14-3(T) has been deposited as DSM 17835(T) and as CIP 109839(T).

  19. Phospholipids and protein adaptation of Pseudomonas sp. to the xenoestrogen tributyltin chloride (TBT).

    Science.gov (United States)

    Bernat, Przemysław; Siewiera, Paulina; Soboń, Adrian; Długoński, Jerzy

    2014-09-01

    A tributyltin (TBT)-resistant strain of Pseudomonas sp. isolated from an overworked car filter was tested for its adaptation to TBT. The isolate was checked for organotin degradation ability, as well as membrane lipid and cellular protein composition in the presence of TBT. The phospholipid profiles of bacteria, grown with and without increased amounts of TBT, were characterized using liquid chromatography/electrospray ionization/mass spectrometry. The strain reacted to the biocide by changing the composition of its phospholipids. TBT induced a twofold decline in the amounts of many molecular species of phosphatidylglycerol and an increase in the levels of phosphatidic acid (by 58%) and phosphatidylethanolamine (by 70%). An increase in the degree of saturation of phospholipid fatty acids of TBT exposed Pseudomonas sp. was observed. These changes in the phospholipid composition and concentration reflect the mechanisms which support optimal lipid ordering in the presence of toxic xenobiotic. In the presence of TBT the abundances of 16 proteins, including TonB-dependent receptors, porins and peroxidases were modified, which could indicate a contribution of some enzymes to TBT resistance.

  20. Biodegradation of reactive textile dye Red BLI by an isolated bacterium Pseudomonas sp. SUK1.

    Science.gov (United States)

    Kalyani, D C; Patil, P S; Jadhav, J P; Govindwar, S P

    2008-07-01

    A novel bacterial strain capable of decolorizing reactive textile dye Red BLI is isolated from the soil sample collected from contaminated sites of textile industry from Solapur, India. The bacterial isolate was identified as Pseudomonas sp. SUK1 on the basis of 16S rDNA analysis. The Pseudomonas sp. SUK1 decolorized Red BLI (50 mg l(-1)) 99.28% within 1h under static anoxic condition at pH range from 6.5 to 7.0 and 30 degrees C. This strain has ability to decolorize various reactive textile dyes. UV-Vis spectroscopy, FTIR and TLC analysis of samples before and after dye decolorization in culture medium confirmed decolorization of Red BLI. A significant increase in the activities of aminopyrine N-demethylase and NADH-DCIP reductase in cells obtained after decolorization indicates involvement of these enzymes in the decolorization process. Phytotoxicity testing with the seeds of Sorghum vulgare and Phaseolus mungo, showed more sensitivity towards the dye, while the products obtained after dye decolorization does not have any inhibitory effects.

  1. Production and optimization of curdlan produced by Pseudomonas sp. QL212.

    Science.gov (United States)

    Yang, Min; Zhu, Ying; Li, Yumei; Bao, Jie; Fan, Xiangyu; Qu, Yanhong; Wang, Yiwei; Hu, Zhiheng; Li, Qiang

    2016-08-01

    Curdlan is a polysaccharide that consists of β-1,3-linked glucose residues. A polysaccharide-producing bacterium isolated from soil samples was identified as Pseudomonas sp. QL212. The polysaccharide was purified to homogeneity via sequential ethanol precipitation, deproteinization, CM ion-exchange, and gel chromatography sequentially. Analysis of the purified polysaccharide revealed that it consisted of many glucosyl residues, and its molecular weight was only 6.18×10(5)Da. This low molecular weight endowed it with excellent solubility. Infrared and nuclear magnetic resonance spectral analysis confirmed that the polysaccharide was curdlan. Single-factor and Response surface methodology experiments were used to optimize the culture medium and conditions. The optimal culture conditions consisted of seed culture age of 12h, and an incubation temperature of 30°C, with 10% inoculum and a total fluid volume of 75mL in a 250-mL Erlenmeyer flask. The maximum curdlan yield of about 5.92gL(-1) was achieved with an optimal medium consisting of 30.11gL(-1) of sucrose, 5.94gL(-1) of yeast extract, and an initial pH of 8.03. To our best knowledge, this is the highest reported yield of curdlan produced by Pseudomonas sp., and the curdlan production medium components were much simpler than those in previous reports.

  2. Optimization for Microbial Degradation of Dibenzothiophene by Pseudomonas sp. LKY-5 Using Response Surface Methodology

    Institute of Scientific and Technical Information of China (English)

    Li Lin; Zhao Chaocheng; Liu Qiyou; Zhang Yunbo; Liu Chunshuang; Xue Jianliang

    2014-01-01

    In this research, the degradation of dibenzothiophene (DBT) was investigated by using Pseudomonas sp. LKY-5 isolated from oil contaminated soil. The response surface methodology (RSM) based on the Box-Behnken design (BBD) was applied for evaluating the interactive effects of four independent variables including substrate concentration, tempera-ture, pH and agitation rate on the DBT removal response. A total of 29 experiments for four factors at three levels were conducted in present study. A second-order regression model was then developed, and the analysis of variance (ANOVA) illustrated that the proposed quadratic model could be utilized to navigate the design space. The value of determination coefif-cient (R2=0.953 4) indicated a satisfactory agreement between the quadratic model and the experimental data. It was found that DBT removal was more signiifcantly affected (P<0.000 1) by substrate concentration compared with other three parameters. An 100%degradation of DBT could be obtained by Pseudomonas sp. LKY-5 at a substrate concentration of 100 mg/L.

  3. Two novel cyclic peptides are key components of the antimicrobial activity of the Greenlandic isolate Pseudomonas sp. In5

    DEFF Research Database (Denmark)

    Hennessy, Rosanna Catherine; Phippen, Christopher; Nielsen, Kristian F.

    Pseudomonas sp. are a rich source of secondary metabolites including bioactive non-ribosomal peptides (NRPs) and polyketides. NRPs are synthesised in large assembly lines by multi-domain modular enzymes known as NRP-synthetases (NRPS). Nunamycin and nunapeptin are two cyclic NRPs synthesised...... by the Greenlandic isolate Pseudomonas sp. In5. Nunamycin shows antifungal activity against the basidiomycete Rhizoctonia solani whereas the only partially structure elucidated nunapeptin appears most active against the ascomycete Fusarium graminearum and the oomycete Pythium aphanidermatum. Originally isolated from...

  4. Draft Genome Sequence of Pseudomonas sp. Strain 2-92, a Biological Control Strain Isolated from a Field Plot Under Long-Term Mineral Fertilization.

    Science.gov (United States)

    Adam, Zaky; Tambong, James Tabi; Chen, Qing; Lewis, Christopher T; Lévesque, C André; Xu, Renlin

    2014-01-09

    Pseudomonas sp. strain 2-92, isolated from a Canadian field plot under long-term mineral fertilization, strongly inhibits the growth of Fusarium graminearum, Rhizoctonia solani, and Gaeumannomyces graminis. Here, we report the draft genome sequence of Pseudomonas sp. strain 2-92.

  5. Pseudomonas sihuiensis sp. nov., isolated from a forest soil in South China.

    Science.gov (United States)

    Wu, Min; Wen, Junlin; Chang, Ming; Yang, Guiqin; Zhou, Shungui

    2014-04-01

    A Gram-stain negative, motile, rod-shaped bacterium, designated strain WM-2(T), was isolated from a forest soil in Sihui City, South China, and characterized by means of a polyphasic approach. Growth occurred with 0-5 % (w/v) NaCl (optimum 0-1 %) and at pH 5.0-10.5 (optimum pH 8.5) and 4-40 °C (optimum 30 °C) in Luria-Bertani medium. Comparative 16S rRNA gene sequence analyses showed that strain WM-2(T) is a member of the genus Pseudomonas and most closely related to P. guguanensis, P. oleovorans subsp. lubricantis, P. toyotomiensis, P. alcaliphila and P. mendocina with 97.1-96.6 % sequence similarities. In terms of gyrB and rpoB gene sequences, strain WM-2(T) showed the highest similarity with the type strains of the species P. toyotomiensis and P. alcaliphila. The DNA-DNA relatedness values of strain WM-2(T) with P. guguanensis and P. oleovorans subsp. lubricantis was 48.7 and 37.2 %, respectively. Chemotaxonomic characteristics (the main ubiquinone Q-9, major fatty acids C18:1 ω7c/C18:1 ω6c, C16:0 and C16:1 ω7c/C16:1 ω6c and DNA G+C content 65.2 ± 0.7 mol%) were similar to those of members of the genus Pseudomonas. Polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, an unknown aminophospholipid, an unknown phospholipid and five unknown lipids. According to the results of polyphasic analyses, strain WM-2(T) represents a novel species in the genus Pseudomonas, for which the name Pseudomonas sihuiensis sp. nov. is proposed. The type strain is WM-2(T) (=KCTC 32246(T)=CGMCC 1.12407(T)).

  6. Pseudomonas coleopterorum sp. nov., a cellulase-producing bacterium isolated from the bark beetle Hylesinus fraxini.

    Science.gov (United States)

    Menéndez, Esther; Ramírez-Bahena, Martha H; Fabryová, Anna; Igual, José M; Benada, Oldrich; Mateos, Pedro F; Peix, Alvaro; Kolařík, Miroslav; García-Fraile, Paula

    2015-09-01

    We isolated a strain coded Esc2Am(T) during a study focused on the microbial diversity of adult specimens of the bark beetle Hylesinus fraxini. Its 16S rRNA gene sequence had 99.4% similarity with respect to its closest relative, Pseudomonas rhizosphaerae IH5(T). The analysis of partial sequences of the housekeeping genes rpoB, rpoD and gyrB confirmed that strain Esc2Am(T) formed a cluster with P. rhizosphaerae IH5(T) clearly separated from the remaining species of the genus Pseudomonas. Strain Esc2Am(T) had polar flagella and could grow at temperatures from 4 °C to 30 °C. The respiratory quinone was Q9 and the main fatty acids were C16 : 0, C18 : 1ω7c and/or C18 : 1ω6c in summed feature 8 and C16 : 1ω7c and/or C16 : 1ω6c in summed feature 3. DNA-DNA hybridization results showed 51% relatedness with respect to P. rhizosphaerae IH5(T). Oxidase, catalase and urease-positive, the arginine dihydrolase system was present but nitrate reduction and β-galactosidase production were negative. Aesculin hydrolysis was positive. Based on the results from the genotypic, phenotypic and chemotaxonomic analyses, we propose the classification of strain Esc2Am(T) as representing a novel species of the genus Pseudomonas, for which we propose the name Pseudomonas coleopterorum sp. nov. The type strain is Esc2Am(T) ( = LMG 28558(T)= CECT 8695(T)).

  7. Plant growth promoting potential of pseudomonas sp. SP0113 isolated from potable water from a closed water well

    Directory of Open Access Journals (Sweden)

    Przemieniecki Wojciech Sebastian

    2015-01-01

    Full Text Available The Pseudomonas sp. SP0113 strain from a partially closed aquatic environment was identified as a plant growth promoting bacterium (PGPB. Laboratory tests revealed that PS0113 has multiple plant growth promoting traits, including mineral phosphate solubilizing ability, ammonifying ability that increases nitrogen availability for plants via the root system, and phosphatase activity that plays an important role in organic phosphorus mineralization. Tricalcium phosphate (Ca3(PO42 solubilizing ability was described as average (2-3 mm after 7 days of incubation and as high (>3 mm after 14 days of incubation. The analyzed bacterium was an antagonist of major crop pathogenic fungi. A high degree of pathogen growth inhibition was reported with regard to Rhizoctonia solani (38%, whereas the tested strain's ability to inhibit the growth of fungi of the genera Fusarium and Microdochium nivalis was somewhat lower at 20-29%. The bacterium proliferated in Roundup 360 SL solutions with concentrations of 0.1, 1 and 10 mg•ml-1.

  8. The nitrogen-fixation island insertion site is conserved in diazotrophic Pseudomonas stutzeri and Pseudomonas sp. isolated from distal and close geographical regions.

    Directory of Open Access Journals (Sweden)

    Anastasia Venieraki

    Full Text Available The presence of nitrogen fixers within the genus Pseudomonas has been established and so far most isolated strains are phylogenetically affiliated to Pseudomonas stutzeri. A gene ortholog neighborhood analysis of the nitrogen fixation island (NFI in four diazotrophic P. stutzeri strains and Pseudomonas azotifigens revealed that all are flanked by genes coding for cobalamin synthase (cobS and glutathione peroxidise (gshP. The putative NFIs lack all the features characterizing a mobilizable genomic island. Nevertheless, bioinformatic analysis P. stutzeri DSM 4166 NFI demonstrated the presence of short inverted and/or direct repeats within both flanking regions. The other P. stutzeri strains carry only one set of repeats. The genetic diversity of eleven diazotrophic Pseudomonas isolates was also investigated. Multilocus sequence typing grouped nine isolates along with P. stutzeri and two isolates are grouped in a separate clade. A Rep-PCR fingerprinting analysis grouped the eleven isolates into four distinct genotypes. We also provided evidence that the putative NFI in our diazotrophic Pseudomonas isolates is flanked by cobS and gshP genes. Furthermore, we demonstrated that the putative NFI of Pseudomonas sp. Gr65 is flanked by inverted repeats identical to those found in P. stutzeri DSM 4166 and while the other P. stutzeri isolates harbor the repeats located in the intergenic region between cobS and glutaredoxin genes as in the case of P. stutzeri A1501. Taken together these data suggest that all putative NFIs of diazotrophic Pseudomonas isolates are anchored in an intergenic region between cobS and gshP genes and their flanking regions are designated by distinct repeats patterns. Moreover, the presence of almost identical NFIs in diazotrophic Pseudomonas strains isolated from distal geographical locations around the world suggested that this horizontal gene transfer event may have taken place early in the evolution.

  9. The nitrogen-fixation island insertion site is conserved in diazotrophic Pseudomonas stutzeri and Pseudomonas sp. isolated from distal and close geographical regions.

    Science.gov (United States)

    Venieraki, Anastasia; Dimou, Maria; Vezyri, Eleni; Vamvakas, Alexandros; Katinaki, Pagona-Artemis; Chatzipavlidis, Iordanis; Tampakaki, Anastasia; Katinakis, Panagiotis

    2014-01-01

    The presence of nitrogen fixers within the genus Pseudomonas has been established and so far most isolated strains are phylogenetically affiliated to Pseudomonas stutzeri. A gene ortholog neighborhood analysis of the nitrogen fixation island (NFI) in four diazotrophic P. stutzeri strains and Pseudomonas azotifigens revealed that all are flanked by genes coding for cobalamin synthase (cobS) and glutathione peroxidise (gshP). The putative NFIs lack all the features characterizing a mobilizable genomic island. Nevertheless, bioinformatic analysis P. stutzeri DSM 4166 NFI demonstrated the presence of short inverted and/or direct repeats within both flanking regions. The other P. stutzeri strains carry only one set of repeats. The genetic diversity of eleven diazotrophic Pseudomonas isolates was also investigated. Multilocus sequence typing grouped nine isolates along with P. stutzeri and two isolates are grouped in a separate clade. A Rep-PCR fingerprinting analysis grouped the eleven isolates into four distinct genotypes. We also provided evidence that the putative NFI in our diazotrophic Pseudomonas isolates is flanked by cobS and gshP genes. Furthermore, we demonstrated that the putative NFI of Pseudomonas sp. Gr65 is flanked by inverted repeats identical to those found in P. stutzeri DSM 4166 and while the other P. stutzeri isolates harbor the repeats located in the intergenic region between cobS and glutaredoxin genes as in the case of P. stutzeri A1501. Taken together these data suggest that all putative NFIs of diazotrophic Pseudomonas isolates are anchored in an intergenic region between cobS and gshP genes and their flanking regions are designated by distinct repeats patterns. Moreover, the presence of almost identical NFIs in diazotrophic Pseudomonas strains isolated from distal geographical locations around the world suggested that this horizontal gene transfer event may have taken place early in the evolution.

  10. Antimicrobial resistance in Pseudomonas sp. causing infections in trauma patients: A 6 year experience from a south asian country

    Directory of Open Access Journals (Sweden)

    Nonika Rajkumari

    2014-01-01

    Full Text Available Drug resistance to Pseudomonas sp. has spread to such a level irrespective of the type of patients, that its pattern of distribution and antibiotic resistance needs to be studied in detail, especially in trauma patients and hence the study. A 6 year study was carried out among trauma patients to see the trend and type of resistance prevalent in the apex hospital for trauma care in India among nonduplicate isolates where multidrug-resistance (MDR, cross-resistance and pan-drug resistance in Pseudomonas sp. were analyzed. Of the total 2,269 isolates obtained, the species, which was maximally isolated was Pseudomonas aeruginosa (2,224, 98%. The highest level of resistance was seen in tetracycline (2,166, 95.5%, P < 0.001 and chloramphenicol (2,160, 95.2%, P < 0.001 and least in meropenem (1,739, 76.7%, P < 0.003. Of the total, 1,692 (74.6% isolates were MDR in which P. aeruginosa (75% were maximum. MDR Pseudomonas is slowing increasing since the beginning of the study period. Of 1,797 imipenem-resistant P. aeruginosa isolated during the study period, 1,763 (98% showed resistance to ciprofloxacin or levofloxacin, suggesting that cross-resistance may have developed for imipenem due to prior use of fluoroquinolones. Antibiotic resistance in Pseudomonas sp. is fast becoming a problem in trauma patients, especially in those who requires prolong hospital stay, which calls for proper antimicrobial stewardship.

  11. Biosurfactant-producing microorganism Pseudomonas sp. SB assists the phytoremediation of DDT-contaminated soil by two grass species.

    Science.gov (United States)

    Wang, Beibei; Wang, Qingling; Liu, Wuxing; Liu, Xiaoyan; Hou, Jinyu; Teng, Ying; Luo, Yongming; Christie, Peter

    2017-09-01

    Phytoremediation together with microorganisms may confer the advantages of both phytoremediation and microbial remediation of soils containing organic contaminants. In this system biosurfactants produced by Pseudomonas sp. SB may effectively help to increase the bioavailability of organic pollutants and thereby enhance their microbial degradation in soil. Plants may enhance the rhizosphere environment for microorganisms and thus promote the bioremediation of contaminants. In the present pot experiment study, dichlorodiphenyltrichloroethane (DDT) residues underwent an apparent decline after soil bioremediation compared with the original soil. The removal efficiency of fertilizer + tall fescue, fertilizer + tall fescue + Pseudomonas, fertilizer + perennial ryegrass, and fertilizer + perennial ryegrass + Pseudomonas treatments were 59.4, 65.6, 69.0, and 65.9%, respectively, and were generally higher than that in the fertilizer control (40.3%). Principal coordinates analysis (PCoA) verifies that plant species greatly affected the soil bacterial community irrespective of inoculation with Pseudomonas sp. SB. Furthermore, community composition analysis shows that Proteobacteria, Acidobacteria and Actinobacteria were the three dominant phyla in all groups. In particular, the relative abundance of Pseudomonas for fertilizer + tall fescue + Pseudomonas (0.25%) was significantly greater than fertilizer + tall fescue and this was related to the DDT removal efficiency. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Pseudomonas songnenensis sp. nov., isolated from saline and alkaline soils in Songnen Plain, China.

    Science.gov (United States)

    Zhang, Lei; Pan, Yuanyuan; Wang, Kaibiao; Zhang, Xiaoxia; Zhang, Shuang; Fu, Xiaowei; Zhang, Cheng; Jiang, Juquan

    2015-03-01

    The strain NEAU-ST5-5(T) was isolated from the saline and alkaline soil in Songnen Plain, North East of China. The bacterium was found to be aerobic, Gram-stain negative, rod-shaped and motile by means of several polar flagella. It forms yellow-orange colonies with a radial wrinkled surface. Phylogenetic analyses based on the separate 16S rRNA gene sequences and concatenated 16S rRNA, gyrB and rpoD gene sequences indicated that it belongs to the genus Pseudomonas in the class Gammaproteobacteria. Strain NEAU-ST5-5(T) shows gene sequence similarities of 98.8-97.1 % for 16S rRNA, 90.5-78.4 % for gyrB and 90.4-71.1 % for rpoD with type strains of the closely related species of the genus Pseudomonas, respectively. DNA-DNA hybridization relatedness between strain NEAU-ST5-5(T) and type strains of the most closely related species, Pseudomonas stutzeri DSM 5190(T), P. xanthomarina DSM 18231(T), P. kunmingensis CGMCC 1.12273(T), P. alcaliphila DSM 17744(T) and P. oleovorans subsp. lubricantis DSM 21016(T) were 43 ± 1 to 25 ± 2 %. The major fatty acids (>10 %) were determined to be C18:1 ω7c/C18:1 ω6c, C16:1 ω7c/C16:1 ω6c and C16:0, the predominant respiratory quinone was identified as ubiquinone 9 and polar lipids were found to consist of phosphatidylethanolamine, phosphatidylglycerol, diphosphatidylglycerol, one unknown phospholipid, one unidentified aminophospholipid and one unknown lipid. The genotypic, chemotaxonomic and phenotypic analysis indicated that strain NEAU-ST5-5(T) represents a novel species of the genus Pseudomonas, for which the name Pseudomonas songnenensis sp. nov. is proposed. The type strain is NEAU-ST5-5(T) (=ACCC 06361(T) = DSM 27560(T)).

  13. Pseudomonas yamanorum sp. nov., a psychrotolerant bacterium isolated from a subantarctic environment.

    Science.gov (United States)

    Arnau, Víctor Gonzalo; Sánchez, Leandro Arturo; Delgado, Osvaldo Daniel

    2015-02-01

    A psychrotolerant strain, 8H1(T), was isolated from soil samples collected in Isla de los Estados, Ushuaia, Argentina. Cells were Gram-negative, aerobic, straight rods, occurring singly or in pairs, non-spore-forming and motile by means of two polar flagella. The isolate was able to grow in the range 4-35 °C, with optimum growth at 28 °C. The predominant cellular fatty acids were summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c), C16 : 0 and summed feature 8 (C18 : 1ω6c and/or C18 : 1ω7c). The polar lipid pattern of strain 8H1(T) comprised phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine and an unknown phospholipid. Ubiquinone 9 (Q-9) was the predominant lipoquinone. The DNA G+C content was 59.8 mol%. 16S rRNA gene sequence-based phylogeny suggested the affiliation of strain 8H1(T) to the 'Pseudomonas fluorescens group', displaying ≥98.5 % sequence similarity to 29 type strains. A multilocus sequence analysis (MLSA) study performed by concatenating 16S rRNA, gyrB, rpoD and rpoB gene sequences showed that isolate 8H1(T) could be discriminated from closely related species of the genus Pseudomonas and placed in the 'Pseudomonas gessardii subgroup', including the species with the highest MLSA sequence similarities: Pseudomonas brenneri (96.2 %), P. gessardii (96.1 %), P. proteolytica (96.0 %), P. meridiana (96.0 %) and P. mucidolens (95.4 %). DNA-DNA hybridization analysis between 8H1(T) and the type strains of these closely related species revealed relatedness values of 27.0, 8.8, 41.2, 39.7 and 46.1 %, respectively. These results, together with differences in several phenotypic features, support the classification of a novel species, for which the name Pseudomonas yamanorum sp. nov. is proposed. The type strain is 8H1(T) ( = DSM 26522(T) = CCUG 63249(T) = LMG 27247(T)).

  14. Draft Genome Sequence of Pseudomonas sp. Strain In5 Isolated from a Greenlandic Disease Suppressive Soil with Potent Antimicrobial Activity

    DEFF Research Database (Denmark)

    Hennessy, Rosanna C.; Glaring, Mikkel Andreas; Frydenlund Michelsen, Charlotte;

    2015-01-01

    Pseudomonas sp. In5 is an isolate of disease suppressive soil with potent activity against pathogens. Its antifungal activity has been linked to a gene cluster encoding nonribosomal peptide synthetases producing the peptides nunamycin and nunapeptin. The genome sequence will provide insight...... into the genetics behind the antimicrobial activity of this strain....

  15. Long-Term induction of defense gene expression in potato by Pseudomonas sp. LBUM223 and Streptomyces scabies

    NARCIS (Netherlands)

    Arseneault, T.; Pieterse, C.M.J.; Gérin-Ouellet, M.; Goyer, C.; Filion, M.

    2014-01-01

    Streptomyces scabies is a causal agent of common scab of potato, which generates necrotic tuber lesions. We have previously demonstrated that inoculation of potato plants with phenazine-1-carboxylic acid (PCA)-producing Pseudomonas sp. LBUM223 could significantly reduce common scab symptoms. In the

  16. Long-term induction of defense gene expression in potato by pseudomonas sp. LBUM223 and streptomyces scabies

    NARCIS (Netherlands)

    Arseneault, Tanya; Pieterse, Corné M J; Gérin-Ouellet, Maxime; Goyer, Claudia; Filion, Martin

    2014-01-01

    Streptomyces scabies is a causal agent of common scab of potato, which generates necrotic tuber lesions. We have previously demonstrated that inoculation of potato plants with phenazine-1-carboxylic acid (PCA)- producing Pseudomonas sp. LBUM223 could significantly reduce common scab symptoms. In the

  17. Involvement of phenazines and biosurfactants in biocontrol of Pythium myriotylum root rot on cocoyam by Pseudomonas sp. CMR12A

    Science.gov (United States)

    Pseudomonas sp. CMR12a was isolated from the rhizosphere of the tropical tuber crop cocoyam and produces both phenazines and cyclic lipopeptide (CLP) biosurfactants. CMR12a was shown to be an efficient biocontrol agent of P. myriotylum on cocoyam. To assess the importance of phenazine and biosurfact...

  18. Magnetite nanoparticle aided immobilization of Pseudomonas sp. GBS.5 for carbazole degradation

    Directory of Open Access Journals (Sweden)

    Poorva Mehndiratta

    2014-12-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 Pseudomonas sp. GBS.5 is a newly isolated biosurfactant producing and carbazole degrading bacterium. In the present study, this bacterium was coated with magnetite nanoparticles, synthesized using co-precipitation method. Scanning electron microscopy (SEM studies confirmed the coating of the bacterial surface with these nanoparticles. Degradation activity of the coated cells obtained was 1.4 ppm/min as compared to 0.32 ppm/min for free cells and could be reused for five different cycles. These results indicate that magnetite nanoparticle can be efficiently used for the immobilization of biosurfactant producing bacteria involved in the degradation of polyaromatic compounds.

  19. Pseudomonas sp. xylanase for clarification of Mausambi and Orange fruit juice

    Science.gov (United States)

    Sharma, Pawan Kumar; Chand, Duni

    2012-07-01

    Xylanase can be usd for many Industrial applications and juice clarification is one of them. Pseudomonas sp. xylanase was used for fruit juice clarification in free State. Maximum amount of juice clarification was in case of Mausambi juice was observed at 40 C∞ and 52 hours, in case of free enzyme treated juice there is 46.9% increase in clarity and 1.7 fold increase in reducing sugars of the juice and enzyme dose was optimized as 8U with maximum flow rate of 6 ml/min at this dose. In case of orange juice in free enzyme treated juice maximum clarity was observed at 40 C∞ and 52 hours, juice was found to be 42.14 % clear with increase of 1.9 fold of reducing sugars, enzyme dose optimized was 8.06U with maximum flow rate of 0.86 ml/min.

  20. Ageing of atrazine in manure amended soils assessed by bioavailability to Pseudomonas sp. strain ADP

    DEFF Research Database (Denmark)

    Glæsner, Nadia; Bælum, Jacob; Strobel, Bjarne W.;

    2014-01-01

    bacteria Pseudomonas sp. strain ADP. Throughout an ageing period of 90 days bioavailability was investigated at days 1, 10, 32, 60 and 90, where ~108 cells g−1 of the ADP strain was inoculated to the 14C-atrazine exposed soil and 14CO2 was collected over 7 days as a measure of mineralized atrazine. Even...... though the bioavailable residue decreased in all of the three soils as time proceeded, we found that ageing occurred faster in the topsoils rich in organic carbon than in subsoil. For one topsoil rich in organic carbon content, Simmelkær, we observed a higher degree of ageing when treated with manure....... Contrarily, sorption experiments showed less sorption to Simmelkær treated with manure than the untreated soil indicating that sorption processes are not the only mechanisms of ageing. The other topsoil low in organic carbon content, Ringe, showed no significant difference in ageing between the manure...

  1. Influence of multiple bioprocess parameters on production of lipase from Pseudomonas sp. BWS-5

    Directory of Open Access Journals (Sweden)

    Balwinder Singh Sooch

    2013-10-01

    Full Text Available The aim of the present work was to study the influence of multiple bioprocess parameters for the maximum production of lipase from Pseudomonas sp. BWS-5. The culture reached the stationary phase of growth after 36h of incubation when the maximum lipase production was obtained at flask level. The different media components such as carbon sources, nitrogen sources, trace elements and process parameters such as the pH of the medium, temperature and time of incubation, agitation/stationary conditions, etc. were optimized at flask level and at bioreactor level. The maximum enzyme production of 298 IU/mL was obtained with the use of simple medium with pH 6.5 containing glucose (1 %, w/v, peptone (3 %, w/v and KCl (0.05 %, w/v after 30h of incubation at 37°C under agitation (200 rpm conditions with 0.75 vvm of air supply.

  2. Production and characterization of biosurfactant produced by a novel Pseudomonas sp. 2B.

    Science.gov (United States)

    Aparna, A; Srinikethan, G; Smitha, H

    2012-06-15

    Biosurfactant-producing bacteria were isolated from terrestrial samples collected in areas contaminated with petroleum compounds. Isolates were screened for biosurfactant production using Cetyl Tri Ammonium Bromide (CTAB)-Methylene blue agar selection medium and the qualitative drop-collapse test. An efficient bacterial strain was selected based on rapid drop collapse activity and highest biosurfactant production. The biochemical characteristics and partial sequenced 16S rRNA gene of isolate, 2B, identified the bacterium as Pseudomonas sp. Five different low cost carbon substrates were evaluated for their effect on biosurfactant production. The maximum biosurfactant synthesis (4.97 g/L) occurred at 96 h when the cells were grown on modified PPGAS medium containing 1% (v/v) molasses at 30 °C and 150 rpm. The cell free broth containing the biosurfactant could reduce the surface tension to 30.14 mN/m. The surface active compound showed emulsifying activity against a variety of hydrocarbons and achieved a maximum emulsion index of 84% for sunflower oil. Compositional analysis of the biosurfactant reveals that the extracted biosurfactant was a glycolipid type, which was composed of high percentages of lipid (∼65%, w/w) and carbohydrate (∼32%, w/w). Fourier transform infrared (FT-IR) spectrum of extracted biosurfactant indicates the presence of carboxyl, hydroxyl and methoxyl functional groups. The mass spectra (MS) shows that dirhamnolipid (l-rhamnopyranosyl-l-rhamnopyranosyl-3-hydroxydecanoyl-3-hydroxydecanoate, Rha-Rha-C(10)-C(10)) was detected in abundance with the predominant congener monorhamnolipid (l-rhamnopyranosyl-β-hydroxydecanoyl-β-hydroxydecanoate, Rha-C(10)-C(10)). The crude oil recovery studies using the biosurfactant produced by Pseudomonas sp. 2B suggested its potential application in microbial enhanced oil recovery and bioremediation.

  3. Biodegradation of the organophosphorus insecticide diazinon by Serratia sp. and Pseudomonas sp. and their use in bioremediation of contaminated soil.

    Science.gov (United States)

    Cycoń, Mariusz; Wójcik, Marcin; Piotrowska-Seget, Zofia

    2009-07-01

    An enrichment culture technique was used for the isolation of bacteria responsible for biodegradation of diazinon in soil. Three bacterial strains were screened and identified by MIDI-FAME profiling as Serratia liquefaciens, Serratia marcescens and Pseudomonas sp. All isolates were able to grow in mineral salt medium (MSM) supplemented with diazinon (50 mgL(-1)) as a sole carbon source, and within 14d 80-92% of the initial dose of insecticide was degraded by the isolates and their consortium. Degradation of diazinon was accelerated when MSM was supplemented with glucose. However, this process was linked with the decrease of pH values, after glucose utilization. Studies on biodegradation in sterilized soil showed that isolates and their consortium exhibited efficient degradation of insecticide (100mg kg(-1) soil) with a rate constant of 0.032-0.085d(-1), and DT(50) for diazinon was ranged from 11.5d to 24.5d. In contrast, degradation of insecticide in non-sterilized soil, non-supplemented earlier with diazinon, was characterized by a rate constant of 0.014d(-1) and the 7-d lag phase, during which only 2% of applied dose was degraded. The results suggested a strong correlation between microbial activity and chemical processes during diazinon degradation. Moreover, isolated bacterial strains may have potential for use in bioremediation of diazinon-contaminated soils.

  4. Description of Pseudomonas asuensis sp. nov. from biological soil crusts in the Colorado plateau, United States of America.

    Science.gov (United States)

    Reddy, Gundlapally Sathyanarayana; Garcia-Pichel, Ferran

    2015-01-01

    A Gram-negative, aerobic, non spore-forming, non-motile, rod-shaped, yellow pigmented bacterium CP155-2(T) was isolated from a biological soil crusts sample collected in the Colorado plateau, USA and subjected to polyphasic taxonomic characterization. Strain CP155-2(T) contained summed feature 3 (C(16:1)ω5c/C(16:1)ω7c) and C(18:1)ω7c as major fatty acids and diphosphatidylglycerol (DPG) along with phosphatidylethanolamine (PE) and phosphatidylglycerol (PG) as major polar lipids. Based on these characteristics CP155-2(T) was assigned to the genus Pseudomonas. Phylogenetic analysis based on 16S rRNA gene sequence further confirmed the affiliation of CP155-2(T) to the genus Pseudomonas and showed a 16S rRNA gene sequence similarity of less than 98.7% with already described species of the genus. Pseudomonas luteola, Pseudomonas zeshuii, and Pseudomonas duriflava were identified as the closest species of the genus Pseudomonas with 16S rRNA gene sequence similarities of 98.7%, 98.6%, and 96.9%, respectively. The values for DNA¨CDNA relatedness between CP155-2(T) and Pseudomonas luteola and Pseudomonas zeshuii were 23% and 14% respectively a value below the 70% threshold value, indicating that strain CP155-2(T) belongs to a novel taxon of the genus Pseudomonas lineage. The novel taxon status was strengthened by a number of phenotypic differences wherein CP155-2(T) was positive for oxidase, negative for gelatin hydrolysis, could utilize D-cellobiose, D-raffinose, L-rhamnose, D-sorbitol but not L-aspartic acid and L-glutamic acid. Based on the collective differences strain CP155-2(T) exhibited, it was identified as a novel species and the name Pseudomonas asuensis sp. nov. was proposed. The type strain of Pseudomonas asuensis sp. nov. is CP155-2(T) (DSM 17866(T) =ATCC BAA-1264(T) =JCM13501(T) =KCTC 32484(T)).

  5. Molecular characterization of a novel family-46 chitosanase from Pseudomonas sp. A-01.

    Science.gov (United States)

    Ando, Akikazu; Saito, Akihiro; Arai, Sayaka; Usuda, Sakiko; Furuno, Maiko; Kaneko, Naomi; Shida, Osamu; Nagata, Yoshiho

    2008-08-01

    Pseudomonas sp. A-01, isolated as a strain with chitosan-degrading activity, produced a 28 kDa chitosanase. Following purification of the chitosanase (Cto1) and determination of its N-terminal amino acid sequence, the corresponding gene (cto1) was cloned by a reverse-genetic technique. The gene encoded a protein, composed of 266 amino acids, including a putative signal sequence (1-28), that showed an amino acid sequence similar to known family-46 chitosanases. Cto1 was successfully overproduced and was secreted by a Brevibacillus choshinensis transformant carrying the cto1 gene on expression plasmid vector pNCMO2. The purified recombinant Cto1 protein was stable at pH 5-8 and showed the best chitosan-hydrolyzing activity at pH 5. Replacement of two acidic amino acid residues, Glu23 and Asp41, which correspond to previously identified active centers in Streptomyces sp. N174 chitosanase, with Gln and Asn respectively caused a defect in the hydrolyzing activity of the enzyme.

  6. Antimicrobial activity of Rhizobium sp. strains against Pseudomonas savastanoi, the agent responsible for the olive knot disease in Algeria

    Directory of Open Access Journals (Sweden)

    2009-06-01

    Full Text Available In the present investigation, six Rhizobium strains isolated from Algerian soil were checked for their antimicrobial activity against Pseudomonas savastanoi, the agent responsible for olive knot disease. Rhizobium sp. ORN 24 and ORN 83 were found to produce antimicrobial activities against Pseudomonas savastanoi. The antimicrobial activity produced by Rhizobium sp. ORN24 was precipitable with ammonium sulfate, between 1,000 and 10,000 KDa molecular weight, heat resistant but sensitive to proteases and detergents. These characteristics suggest the bacteriocin nature of the antimicrobial substance produced by Rhizobium sp. ORN24, named rhizobiocin 24. In contrast, the antimicrobial activity produced by Rhizobium sp. ORN83 was not precipitable with ammonium sulfate; it was smaller than 1,000 KDa molecular weight, heat labile, and protease and detergent resistant. These characteristics could indicate the relationship between the antimicrobial substance produced by Rhizobium sp. ORN 83 and the “small” bacteriocins described in other rhizobia.

    En la presente investigación, seis cepas de Rhizobium aisladas de suelos argelinos fueron estudiadas para conocer su actividad antimicrobiana contra Pseudomonas savastanoi, el agente causante de la tuberculosis del olivo. Rhizobium sp. ORN 24 y ORN 83 produjeron actividad antimicrobiana contra Pseudomonas savastanoi. La actividad antimicrobiana producida por Rhizobium sp. ORN 24 precipitó con sulfato amónico, tuvo un peso molecular entre 1000 y 10000 KDa, fue resistente al calor pero sensible a proteasas y detergentes. Estas características sugieren que la sustancia antimicrobial producida por Rhizobium sp. ORN 24 es la bacteriocina natural conocida como rizobiocina 24. Por el contrario, la actividad antimicrobiana producida por Rhizobium sp. ORN83 no fue precipitable con sulfato amónico, y tuvo un peso molecular menor de 1000 KDa, fue lábil al calor y resistente a detergentes y proteasas. Estas

  7. Pseudomonas cuatrocienegasensis sp. nov., isolated from an evaporating lagoon in the Cuatro Cienegas valley in Coahuila, Mexico.

    Science.gov (United States)

    Escalante, Ana E; Caballero-Mellado, Jesús; Martínez-Aguilar, Lourdes; Rodríguez-Verdugo, Alejandra; González-González, Andrea; Toribio-Jiménez, Jeiry; Souza, Valeria

    2009-06-01

    Nine Gram-negative, rod-shaped, non-spore-forming isolates with identical or very similar repetitive-sequence-based PCR profiles were recovered from an evaporative lagoon in Mexico. Two strains, designated 1N(T) and 3N, had virtually identical 16S rRNA gene sequences and, on the basis of these sequences, were identified as members of the genus Pseudomonas, with Pseudomonas peli R-20805(T) as the closest relative. All nine isolates had practically identical whole-cell protein profiles. The major fatty acids [C(16 : 0,) C(18 : 1)omega7c and summed feature a (C(16 : 1)omega7 and/or C(16 : 1)omega6c)] of strains 1N(T) and 3N supported their affiliation with the genus Pseudomonas. The DNA-DNA reassociation values with respect to P. peli LMG 23201(T) and other closely related Pseudomonas species were <15 %. Physiological and biochemical tests allowed phenotypic differentiation of the strains analysed, including strain 1N(T), from the five phylogenetically closest Pseudomonas species. On the basis of the data obtained by using this polyphasic taxonomic approach, the nine strains represent a novel species, for which the name Pseudomonas cuatrocienegasensis sp. nov. is proposed. The type strain is 1N(T) (=LMG 24676(T)=CIP 109853(T)).

  8. Pseudomonas granadensis sp. nov., a new bacterial species isolated from the Tejeda, Almijara and Alhama Natural Park, Granada, Spain.

    Science.gov (United States)

    Pascual, Javier; García-López, Marina; Bills, Gerald F; Genilloud, Olga

    2015-02-01

    During the course of screening bacterial isolates as sources of as-yet unknown bioactive compounds with pharmaceutical applications, a chemo-organotrophic, Gram-negative bacterium was isolated from a soil sample taken from the Tejeda, Almijara and Alhama Natural Park, Granada, Spain. Strain F-278,770(T) was oxidase- and catalase-positive, aerobic, with a respiratory type of metabolism with oxygen as the terminal electron acceptor, non-spore-forming and motile by one polar flagellum, although some cells had two polar flagella. Phylogenetic analysis of the 16S rRNA, gyrB, rpoB and rpoD genes revealed that strain F-278,770(T) belongs to the Pseudomonas koreensis subgroup (Pseudomonas fluorescens lineage), with Pseudomonas moraviensis, P. koreensis, P. baetica and P. helmanticensis as its closest relatives. Chemotaxonomic traits such as polar lipid and fatty acid compositions and G+C content of genomic DNA corroborated the placement of strain F-278,770(T) in the genus Pseudomonas. DNA-DNA hybridization assays and phenotypic traits confirmed that this strain represents a novel species of the genus Pseudomonas, for which the name Pseudomonas granadensis sp. nov. is proposed. The type strain is F-278,770(T) ( = DSM 28040(T) = LMG 27940(T)).

  9. Bioaccumulation of Cadmium by Pseudomonas Sp. Isolated From Metal Polluted Industrial Region

    Directory of Open Access Journals (Sweden)

    Rinoy Varghese

    2012-10-01

    Full Text Available In the present study, bacterial strains were isolated from soil, sediment and water samples of metal contaminated industrial area and investigated the heavy metal resistance and bioaccumulation potential of the isolates. Cadmium analysis of the samples revealed that Cd concentration varying from 2.31µg L-1 to 8.96 µg L-1 in water, 0.55µg g-1 to 25.44µg g-1 in soil and 0.45µg g-1 to 22.90µg g-1 in sediment. Cadmium resistance studies of the bacterial isolates showed that out of 164 isolates collected most of them showed  low resistance (<500µg/ml and many isolates showed high resistance of  >1500µg/ml. Ten bacterial genera were represented in soil and 11 from water, while only 5 bacterial genera were recorded from sediment samples.  Bacillus, pseudomonas and Enterobacter were found in soil, sediment and water samples. Results of cadmium removal study revealed that with increase in time, the biomass of the selected Pseudomonas sp. increased. Correspondingly, with increase in biomass, the cadmium bioaccumulation was also increased. Relatively an Increased removal of cadmium was observed in the first day of the experiment. About 40% of the cadmium in the experimental flask was reduced while only 5% reduction occurs in the control flasks till the end of the experiment (74hours. Comparatively cadmium showed higher reduction at pH 7. From the results, it could be concluded that the selected bacterial isolates possessed potential in respect of bioaccumulation activity and thus, appeared to be an appropriate nominee in bioremediation processes.DOI: http://dx.doi.org/10.5755/j01.erem.61.3.1268

  10. Biosurfactant produced by novel Pseudomonas sp. WJ6 with biodegradation of n-alkanes and polycyclic aromatic hydrocarbons.

    Science.gov (United States)

    Xia, Wenjie; Du, Zhifeng; Cui, Qingfeng; Dong, Hao; Wang, Fuyi; He, Panqing; Tang, YongChun

    2014-07-15

    Alkanes and polycyclic aromatic hydrocarbons (PAHs) have threatened the environment due to toxicity and poor bioavailability. Interest in degradation of these hazardous materials by biosurfactant-producing bacteria has been steadily increasing in recent years. In this work, a novel biosurfactant-producing Pseudomonas sp. WJ6 was isolated to degrade a wide range of n-alkanes and polycyclic aromatic hydrocarbons. Production of lipopeptide biosurfactant was observed in all biodegradable studies. These lipopeptides were purified and identified by C18 RP-HPLC system and electrospray ionization-mass spectrometry. Results of structural analysis showed that these lipopeptides generated from different hydrocarbons were classified to be surfactin, fengycin and lichenysin. Heavy-oil sludge washing experiments demonstrated that lipopeptides produced by Pseudomonas sp. WJ6 have 92.46% of heavy-oil washing efficiency. The obtained results indicate that this novel bacterial strain and its lipopeptides have great potentials in the environmental remediation and petroleum recovery.

  11. Cloning,expression and characterization of L-cysteine desulfhydrase gene from Pseudomonas sp.TS1138

    Institute of Scientific and Technical Information of China (English)

    YU Yangsheng; BAI Gang; LIU Chunqin; LI Yang; JIN Yongjie; YANG Wenbo

    2007-01-01

    L-cysteine desulthydrase (CD) plays an important role in L-cysteine decomposition.To identify the CD gene in Pseudomonas sp.TS 1138 and investigate its effect on the L-cysteine biosynthetic pathway,the CD gene was cloned from Pseudomonas sp.TS 1138 by polymerase chain reaction (PCR) method.The nucleotide sequence of CD gene was determined to be 1,215 bp,and its homology with other sequences encoding CD was analyzed.Then the CD gene was subcloned into pET-21a(+) vector and expressed in Escherichia coli (E.coli) by isopropyl-β-D-thiogalactopyranoside (IPTG) inducement.The recombinant CD was purified by Ni-NTA His-Bind resin,and its activity was identified by the CD activity staining.The enzymatic properties of the recombinant CD were characterized and its critical role involved in the L-cysteine biosynthetic pathway was also discussed.

  12. Complete genome of Pseudomonas sp. strain L10.10, a psychrotolerant biofertilizer that could promote plant growth.

    Science.gov (United States)

    See-Too, Wah Seng; Lim, Yan-Lue; Ee, Robson; Convey, Peter; Pearce, David A; Yin, Wai-Fong; Chan, Kok Gan

    2016-03-20

    Pseudomonas sp. strain L10.10 (=DSM 101070) is a psychrotolerant bacterium which was isolated from Lagoon Island, Antarctica. Analysis of its complete genome sequence indicates its possible role as a plant-growth promoting bacterium, including nitrogen-fixing ability and indole acetic acid (IAA)-producing trait, with additional suggestion of plant disease prevention attributes via hydrogen cyanide production. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. Plasmid dependence of Pseudomonas sp. strain NK87 enzymes that degrade 6-aminohexanoate-cyclic dimer.

    Science.gov (United States)

    Kanagawa, K; Negoro, S; Takada, N; Okada, H

    1989-06-01

    A bacterial strain, Pseudomonas sp. strain NK87, that can use 6-aminohexanoate-cyclic dimer as the sole source of carbon and nitrogen was newly isolated from wastewater of a factory which produces nylon-6. Two responsible enzymes, 6-aminohexanoate-cyclic-dimer hydrolase (P-EI) and 6-aminohexanoate-dimer hydrolase (P-EII), were found in the NK87 strain, as is the case with Flavobacterium sp. strain KI72, another 6-aminohexanoate-cyclic-dimer-metabolizing bacterium (H. Okada, S. Negoro, H. Kimura, and S. Nakamura, Nature [London] 306:203-206, 1983). The P-EI enzyme is immunologically identical to the 6-aminohexanoate-cyclic-dimer hydrolase of KI72 (F-EI). However, antiserum against the 6-aminohexanoate-dimer hydrolase purified from KI72 (F-EII) did not react with cell extracts of NK87, indicating that the F-EII and P-EII enzymes are immunologically different. Restriction endonuclease analyses show that the NK87 strain harbors at least six plasmids ranging in size from 20 to 80 kilobase pairs (kbp). The P-EI and P-EII genes were cloned in Escherichia coli. Both the P-EI and F-EI probes strongly hybridized with a 23-kbp plasmid in Southern hybridization analyses. The P-EII probe hybridized specifically with an 80-kbp plasmid, but the F-EII probe hybridized with none of the plasmids harbored in NK87. These results indicate that the P-EI gene and P-EII gene are encoded on the 23-kbp and 80-kbp plasmids, respectively.

  14. Decolorization and detoxification of Congo red and textile industry effluent by an isolated bacterium Pseudomonas sp. SU-EBT.

    Science.gov (United States)

    Telke, Amar A; Joshi, Swati M; Jadhav, Sheetal U; Tamboli, Dhawal P; Govindwar, Sanjay P

    2010-04-01

    The 16S rRNA sequence and biochemical characteristics revealed the isolated organism as Pseudomonas sp. SU-EBT. This strain showed 97 and 90% decolorization of a recalcitrant dye, Congo red (100 mg l(-1)) and textile industry effluent with 50% reduction in COD within 12 and 60 h, respectively. The optimum pH and temperature for the decolorization was 8.0 and 40 degrees C, respectively. Pseudomonas sp. SU-EBT was found to tolerate the dye concentration up to 1.0 g l(-1). Significant induction in the activity of intracellular laccase suggested its involvement in the decolorization of Congo red. The metabolites formed after decolorization of Congo red, such as p-dihydroxy biphenyl, 8-amino naphthol 3-sulfonic acid and 3-hydroperoxy 8-nitrosonaphthol were characterized using FTIR and GC-MS. Phytotoxicity study revealed nontoxic nature of the degradation metabolites to Sorghum bicolor, Vigna radiata, Lens culinaris and Oryza sativa plants as compared to Congo red and textile industry effluent. Pseudomonas sp. SU-EBT decolorized several individual textile dyes, dye mixtures and textile industry effluent, thus it is a useful strain for the development of effluent treatment methods in textile processing industries.

  15. Biodegradation of benzalkonium chlorides singly and in mixtures by a Pseudomonas sp. isolated from returned activated sludge

    Energy Technology Data Exchange (ETDEWEB)

    Khan, Adnan Hossain, E-mail: akhan462@uwo.ca [Department of Chemical and Biochemical Engineering, University of Western Ontario, London, ON N6A 5B9 (Canada); Topp, Edward, E-mail: Ed.Topp@AGR.GC.CA [Agriculture and Agri-Food Canada, London, ON N5V 4T3 (Canada); Department of Biology, University of Western Ontario, London, ON N6A 5B7 (Canada); Scott, Andrew, E-mail: Andrew.Scott@AGR.GC.CA [Agriculture and Agri-Food Canada, London, ON N5V 4T3 (Canada); Sumarah, Mark, E-mail: Mark.Sumarah@agr.gc.ca [Agriculture and Agri-Food Canada, London, ON N5V 4T3 (Canada); Macfie, Sheila M., E-mail: smacfie@uwo.ca [Department of Biology, University of Western Ontario, London, ON N6A 5B7 (Canada); Ray, Madhumita B., E-mail: mbhowmic@uwo.ca [Department of Chemical and Biochemical Engineering, University of Western Ontario, London, ON N6A 5B9 (Canada)

    2015-12-15

    Highlights: • Pseudomonas sp. degraded two benzalkonium chlorides: BDDA and BDTA. • Although BDTA biodegraded at low concentration, it inhibited the degradation of BDDA. • For BDDA, two transformation products indicate two sites of bacterial activity. • {sup 14}C-labelled BDDA was mineralized to {sup 14}CO{sub 2} within 300 h. - Abstract: Bactericidal cationic surfactants such as quaternary ammonium compounds (QACs) are widely detected in the environment, and found at mg kg{sup −1} concentrations in biosolids. Although individual QACs are amenable to biodegradation, it is possible that persistence is increased for mixtures of QACs with varying structure. The present study evaluated the biodegradation of benzyl dimethyl dodecyl ammonium chloride (BDDA) singly and in the presence of benzyl dimethyl tetradecyl ammonium chloride (BDTA) using Pseudomonas sp., isolated from returned activated sludge. Growth was evaluated, as was biodegradation using {sup 14}C and HPLC-MS methods. BDTA was more toxic to growth of Pseudomonas sp. compared to BDDA, and BDTA inhibited BDDA biodegradation. The benzyl ring of [U-{sup 14}C-benzyl] BDDA was readily and completely mineralized. The detection of the transformation products benzyl methyl amine and dodecyl dimethyl amine in spent culture liquid was consistent with literature. Overall, this study demonstrates the antagonistic effect of interactions on biodegradation of two widely used QACs suggesting further investigation on the degradation of mixture of QACs in wastewater effluents and biosolids.

  16. Ageing of atrazine in manure amended soils assessed by bioavailability to Pseudomonas sp. strain ADP.

    Science.gov (United States)

    Glæsner, Nadia; Bælum, Jacob; Strobel, Bjarne W; Jacobsen, Carsten S

    2014-04-01

    Animal manure is applied to agricultural land in areas of high livestock production. In the present study, we evaluated ageing of atrazine in two topsoils with and without addition of manure and in one subsoil. Ageing was assessed as the bioavailability of atrazine to the atrazine mineralizing bacteria Pseudomonas sp. strain ADP. Throughout an ageing period of 90 days bioavailability was investigated at days 1, 10, 32, 60 and 90, where ~10(8) cells g(-1) of the ADP strain was inoculated to the (14)C-atrazine exposed soil and (14)CO2 was collected over 7 days as a measure of mineralized atrazine. Even though the bioavailable residue decreased in all of the three soils as time proceeded, we found that ageing occurred faster in the topsoils rich in organic carbon than in subsoil. For one topsoil rich in organic carbon content, Simmelkær, we observed a higher degree of ageing when treated with manure. Contrarily, sorption experiments showed less sorption to Simmelkær treated with manure than the untreated soil indicating that sorption processes are not the only mechanisms of ageing. The other topsoil low in organic carbon content, Ringe, showed no significant difference in ageing between the manure-treated and untreated soil. The present study illustrates that not simply the organic carbon content influences adsorption and ageing of atrazine in soil but the origin and composition of organic matter plays an important role.

  17. Simultaneous heterotrophic nitrification and aerobic denitrification by the marine origin bacterium Pseudomonas sp. ADN-42.

    Science.gov (United States)

    Jin, Ruofei; Liu, Tianqi; Liu, Guangfei; Zhou, Jiti; Huang, Jianyu; Wang, Aijie

    2015-02-01

    Recent research has highlighted the existence of some bacteria that are capable of performing heterotrophic nitrification and have a phenomenal ability to denitrify their nitrification products under aerobic conditions. A high-salinity-tolerant strain ADN-42 was isolated from Hymeniacidon perleve and found to display high heterotrophic ammonium removal capability. This strain was identified as Pseudomonas sp. via 16S rRNA gene sequence analysis. Gene cloning and sequencing analysis indicated that the bacterial genome contains N2O reductase function (nosZ) gene. NH3-N removal rate of ADN-42 was very high. And the highest removal rate was 6.52 mg/L · h in the presence of 40 g/L NaCl. Under the condition of pure oxygen (DO >8 mg/L), NH3-N removal efficiency was 56.9 %. Moreover, 38.4 % of oxygen remained in the upper gas space during 72 h without greenhouse gas N2O production. Keeping continuous and low level of dissolved oxygen (DO <3 mg/L) was helpful for better denitrification performance. All these results indicated that the strain has heterotrophic nitrification and aerobic denitrification abilities, which guarantee future application in wastewater treatment.

  18. A specific antimicrobial protein CAP-1 from Pseudomonas sp. isolated from the jellyfish Cyanea capillata.

    Science.gov (United States)

    Yin, Manman; Liu, Dan; Xu, Feng; Xiao, Liang; Wang, Qianqian; Wang, Beilei; Chang, Yinlong; Zheng, Jiemin; Tao, Xia; Liu, Guoyan; Zhang, Liming

    2016-01-01

    A bacterium strain, designated as CMF-2, was isolated from the jellyfish Cyanea capillata and its culture supernatant exhibited a significant antimicrobial activity. The strain CMF-2 was identified as Pseudomonas sp. based on the morphological, biochemical and physiological characteristics as well as 16S rRNA sequence analysis. In this study, an antimicrobial protein, named as CAP-1, was isolated from the culture of CMF-2 through ammonium sulfate precipitation and gel filtration chromatography. According to the result of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), a major band indicated that the antimicrobial protein had a molecular mass of about 15 kDa, and it was identified as a hypothetical protein by MALDI-TOF-MS analysis and Mascot searching. CAP-1 displayed a broad antimicrobial spectrum against the indicator bacteria and fungus, including Staphylococcus aureus, Escherichia coli, Bacillus subtilis and Candida albicans, especially some marine-derived microorganisms such as Vibrio vulnificus, Vibrio alginolyticus, Vibrio parahaemolyticus, Vibrio cholera, and Vibrio anguillarum, but showed little impact on tumor cells and normal human cells. The protein CAP-1 remained a stable antimicrobial activity in a wide range of temperature (20-80°C) and pH (2-10) conditions. These results suggested that CAP-1 might have a specific antimicrobial function not due to cytotoxicity.

  19. Characterization of a sodium dodecyl sulphate-degrading Pseudomonas sp. strain DRY15 from Antarctic soil.

    Science.gov (United States)

    Halmi, M I E; Hussin, W S W; Aqlima, A; Syed, M A; Ruberto, L; MacCormack, W P; Shukor, M Y

    2013-11-01

    A bacterium capable of biodegrading surfactant sodium dodecyl sulphate (SDS) was isolated from Antarctic soil. The isolate was tentatively identified as Pseudomonas sp. strain DRY15 based on carbon utilization profiles using Biolog GN plates and partial 16S rDNA molecular phylogeny. Growth characteristic studies showed that the bacterium grew optimally at 10 degrees C, 7.25 pH, 1 g l(-1) SDS as a sole carbon source and 2 g l(-1) ammonium sulphate as nitrogen source. Growth was completely inhibited at 5 g l(-1) SDS. At a tolerable initial concentration of 2 g l(-1), approximately 90% of SDS was degraded after an incubation period of eight days. The best growth kinetic model to fit experimental data was the Haldane model of substrate inhibition with a correlation coefficient value of 0.97. The maximum growth rate was 0.372 hr(-1) while the saturation constant or half velocity constant (Ks) and inhibition constant (Ki), were 0.094% and 11.212 % SDS, respectively. Other detergent tested as carbon sources at 1 g l(-1) was Tergitol NP9, Tergitol 15S9, Witconol 2301 (methyl oleate), sodium dodecylbenzene sulfonate (SDBS), benzethonium chloride, and benzalkonium chloride showed Tergitol NP9, Tergitol 15S9, Witconol 2301 and the anionic SDBS supported growth with the highest growth exhibited by SDBS.

  20. [Bioremediation of chlorothalonil-contaminated soil by utilizing Pseudomonas sp. strain CTN-3].

    Science.gov (United States)

    Wang, Guang-Li; Chen, Hong-Hong; Bi, Meng; Li, Shun-Peng

    2012-03-01

    Chlorothalonil is the priority organic pollutant listed by the U.S. Environmental Protection Agency. To utilize the function of microbial degradation in the bioremediation of chlorothalonil-contaminated soil is of practical significance. In this study, a chlorothalonil-degrading Pseudomonas sp. strain CTN-3 isolated from pesticide-contaminated soil was used to examine the chlorothalonil-degrading capacity of the strain and related affecting factors in a microcosm. In sterilized soil, the effect of CTN-3 on chlorothalonil degradation was better than that in unsterilized soil. Various factors, including soil pH, temperature, initial chlorothalonil concentration, and inoculum size, affected the degradation of chlorothalonil by the strain. With the inoculum size of 10(6) CFU x g(-1) soil, the CTN-3 at 15-30 degrees C and pH 5.8-8.3 could effectively degrade 10-200 mg x kg(-1) of chlorothalonil, suggesting that the strain CTN-3 had great potential in the bioremediation of chlorothalonil-contaminated soil.

  1. A study on metabolic prowess of Pseudomonas sp. RPT 52 to degrade imidacloprid, endosulfan and coragen.

    Science.gov (United States)

    Gupta, Manasi; Mathur, Samarth; Sharma, Tarun K; Rana, Manish; Gairola, Ajay; Navani, Naveen K; Pathania, Ranjana

    2016-01-15

    A bacterial strain identified as Pseudomonas sp. RPT 52, was isolated from an agricultural field by soil enrichment technique. The bacterial strain was able to metabolize three different chlorinated pesticides; imidacloprid, endosulfan and coragen (belonging to neonicotinoid, organochlorine and anthranillic diamide categories, respectively). RPT 52 was able to degrade 46.5%, 96.6%, 92.7% and 80.16% of 0.5 mM of imidacloprid, endosulfan α, endosulfan β and coragen, respectively, in minimal medium over a period of 40 h, when provided as sole source of carbon and energy. Degradation kinetics showed that imidacloprid, endosulfan α and endosulfan β followed first order kinetics whereas coragen followed zero order kinetics. Toxicity studies show reduction in toxicity of the parent compound when degraded by RPT 52. Laboratory scale, soil microcosm studies showed that strain RPT 52 is a suitable candidate for bioremediation of endosulfan and coragen contaminated sites. Thus, RPT 52 holds potential for toxicity reduction in the affected environment.

  2. Effects of the bacteriocin PsVP-10 produced by Pseudomonas sp. on sensitive bacterial strains.

    Science.gov (United States)

    Padilla, Carlos; Lobos, Olga; Brevis, Pedro; Abaca, Paulina; Hubert, Elizabeth

    2002-01-01

    The bacteriocin PsVP-10 is a 2.6 Kda peptide which was isolated and purified from Pseudomonas sp. This bacteriocin possesses lethal activity over Enterococcus faecalis, Salmonella typhimurium and Shigella flexneri. The experimental assays showed that the bacteriocin is able to be adsorbed by all cells of these bacterial species and also by their isolated cell walls. It was observed that the resistant mutants and their respective cell walls are unable to adsorb the bacteriocin. Assays performed with spheroplasts obtained from sensitive bacterial species and their resistant mutants show a rapid lethal effect of the bacteriocin PsVP-10. This results indicated furthermore, it is also shown that the optimal pH and temperature for the adsorption were 7.2 and 37 degrees C, respectively. The study carried out with organic solvents like methanol, ethanol, isopropanol and the detergents sodium dodecyl sulfate and triton X-100 showed a moderate inhibition of the bacteriocin lethal action for the Gram negative cells. The enzymes lysozime, protease XIV and trypsine type III-S did not present any effect over the adsorption capacity of the bacteriocin with any of the bacterial species studied.

  3. Metabolic Degradation of 1,4-dichloronaphthalene by Pseudomonas sp. HY

    Directory of Open Access Journals (Sweden)

    Jian Yu

    2015-08-01

    Full Text Available There is increasing concern regarding the adverse health effects of polychlorinated naphthalenes (PCNs. The metabolic degradation of 1,4-dichloronaphthalene (1,4-DCN as a model PCN, was studied using a strain of Pseudomonas sp. HY. The metabolites were analyzed by gas chromatography-mass spectrometry (GC-MS. A series of metabolites including dihydroxy-dichloro-naphthalene, epoxy-dichlorinated naphthalene, dichlorinated naphthol, and dichlorinated salicylic acid were identified. The time-concentration plots of the degradation curves of 1,4-DCN was also obtained from the experiments, which set the initial concentration of 1,4-DCN to 10 mg/L and 20 mg/L, respectively. The results showed that 98% removal could be achieved within 48 h at an initial 1,4-DCN concentration of 10 mg/L. Nevertheless, it took 144 h to reach the same degradation efficiency at an initial concentration of 20 mg/L. The degradation of 1,4-DCN may not remove the chloride ions during the processes and the metabolites may not benefit the bacterial growth. The research suggests a metabolic pathway of 1,4-DCN, which is critical for the treatment of this compound through biological processes.

  4. Erwinia oleae sp. nov., isolated from olive knots caused by Pseudomonas savastanoi pv. savastanoi.

    Science.gov (United States)

    Moretti, Chiaraluce; Hosni, Taha; Vandemeulebroecke, Katrien; Brady, Carrie; De Vos, Paul; Buonaurio, Roberto; Cleenwerck, Ilse

    2011-11-01

    Three endophytic bacterial isolates were obtained in Italy from olive knots caused by Pseudomonas savastanoi pv. savastanoi. Phenotypic tests in combination with 16S rRNA gene sequence analysis indicated a phylogenetic position for these isolates in the genera Erwinia or Pantoea, and revealed two other strains with highly similar 16S rRNA gene sequences (>99 %), CECT 5262 and CECT 5264, obtained in Spain from olive knots. Rep-PCR DNA fingerprinting of the five strains from olive knots with BOX, ERIC and REP primers revealed three groups of profiles that were highly similar to each other. Multilocus sequence analysis (MLSA) based on concatenated partial atpD, gyrB, infB and rpoB gene sequences indicated that the strains constituted a single novel species in the genus Erwinia. The strains showed general phenotypic characteristics typical of the genus Erwinia and whole genome DNA-DNA hybridization data confirmed that they represented a single novel species of the genus Erwinia. The strains showed DNA G+C contents ranging from 54.7 to 54.9 mol%. They could be discriminated from phylogenetically related species of the genus Erwinia by their ability to utilize potassium gluconate, l-rhamnose and d-arabitol, but not glycerol, inositol or d-sorbitol. The name Erwinia oleae sp. nov. (type strain DAPP-PG 531(T)= LMG 25322(T) = DSM 23398(T)) is proposed for this novel taxon.

  5. Insecticidal activity of rhamnolipid isolated from pseudomonas sp. EP-3 against green peach aphid (Myzus persicae).

    Science.gov (United States)

    Kim, Seul Ki; Kim, Young Cheol; Lee, Sunwoo; Kim, Jin Cheol; Yun, Mi Young; Kim, In Seon

    2011-02-09

    Microorganisms capable of growth on oils are potential sources of biopesticides, as they produce complex molecules such as biosurfactants and lipopeptides. These molecules have antimicrobial activity against plant pathogens, but few data are available on their insecticidal activity. The present study describes the insecticidal activity of a rhamnolipid isolated from diesel oil-degrading Pseudomonas sp. EP-3 (EP-3). The treatment of cell-free supernatants of EP-3 grown on glucose-mineral medium for 96 h led to > 80% mortality of aphids (Myzus persicae) within 24 h. Bioassay-guided chromatography coupled with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MADLDI-TOF MS) and (¹H, ¹³C) nuclear magnetic resonance (NMR) analyses was employed to isolate and identify the EP-3 insecticidal metabolites. Dirhamnolipid, with molecular formulas of C₃₂H₅₈O₁₃ and C₃₄H₆₂O₁₃, was identified as a main metabolite exhibiting insecticidal activity against aphids. Dirhamnolipid showed a dose-dependent mortality against aphids, producing about 50% mortality at 40 μg/mL and 100% mortality at 100 μg/mL. Microscopy analyses of aphids treated with dirhamnolipid revealed that dirhamnolipid caused insect death by affecting cuticle membranes. This is the first report of rhamnolipid as an insecticidal metabolite against M. persicae. Rhamnolipid shows potential for use as a pesticide to control agricultural pests.

  6. Genome mining and metabolic profiling of the rhizosphere bacterium Pseudomonas sp. SH-C52 for antimicrobial compounds

    Directory of Open Access Journals (Sweden)

    Menno evan der Voort

    2015-07-01

    Full Text Available The plant microbiome represents an enormous untapped resource for discovering novel genes and bioactive compounds. Previously, we isolated Pseudomonas sp. SH-C52 from the rhizosphere of sugar beet plants grown in a soil suppressive to the fungal pathogen Rhizoctonia solani and showed that its antifungal activity is, in part, attributed to the production of the chlorinated 9-amino-acid lipopeptide thanamycin (Mendes et al. 2011. Science. To get more insight into its biosynthetic repertoire, the genome of Pseudomonas sp. SH-C52 was sequenced and subjected to in silico, mutational and functional analyses. The sequencing revealed a genome size of 6.3 Mb and 5,579 predicted ORFs. Phylogenetic analysis placed strain SH-C52 within the Pseudomonas corrugata clade. In silico analysis for secondary metabolites revealed a total of six nonribosomal peptide synthetase (NRPS gene clusters, including the two previously described NRPS clusters for thanamycin and the 2-amino acid antibacterial lipopeptide brabantamide. Here we show that thanamycin also has activity against an array of other fungi and that brabantamide A exhibits anti-oomycete activity and affects phospholipases of the late blight pathogen Phytophthora infestans. Most notably, mass spectrometry led to the discovery of a third LP, designated thanapeptin, with a 22-amino-acid peptide moiety. Seven structural variants of thanapeptin were found with varying degrees of activity against P. infestans. Of the remaining four NRPS clusters, one was predicted to encode for yet another and unknown lipopeptide with a predicted peptide moiety of 8-amino acids. Collectively, these results show an enormous metabolic potential for Pseudomonas sp. SH-C52, with at least three structurally diverse lipopeptides, each with a different antimicrobial activity spectrum.

  7. Ecofriendly biodegradation and detoxification of Reactive Red 2 textile dye by newly isolated Pseudomonas sp. SUK1

    Energy Technology Data Exchange (ETDEWEB)

    Kalyani, D.C.; Telke, A.A.; Dhanve, R.S. [Department of Biochemistry, Shivaji University, Kolhapur 416004 (India); Jadhav, J.P. [Department of Biochemistry, Shivaji University, Kolhapur 416004 (India)], E-mail: jpj_biochem@unishivaji.ac.in

    2009-04-30

    The aim of this work is to evaluate textile dyes degradation by novel bacterial strain isolated from the waste disposal sites of local textile industries. Detailed taxonomic studies identified the organisms as Pseudomonas species and designated as strain Pseudomonas sp. SUK1. The isolate was able to decolorize sulfonated azo dye (Reactive Red 2) in a wide range (up to 5 g l{sup -1}), at temperature 30 deg. C, and pH range 6.2-7.5 in static condition. This isolate also showed decolorization of the media containing a mixture of dyes. Measurements of COD were done at regular intervals to have an idea of mineralization, showing 52% reduction in the COD within 24 h. Induction in the activity of lignin peroxidase and azoreductase was observed during decolorization of Reactive Red 2 in the batch culture, which represented their role in degradation. The biodegradation was monitored by UV-vis, IR spectroscopy, HPLC. The final product, 2-naphthol was characterized by GC-mass spectroscopy. The phytotoxicity study revealed the degradation of Reactive Red 2 into non-toxic product by Pseudomonas sp. SUK1.

  8. Isolation of plant growth-promoting Pseudomonas sp. PPR8 from the rhizosphere of Phaseolus vulgaris L.

    Directory of Open Access Journals (Sweden)

    Kumar Pankaj

    2016-01-01

    Full Text Available In vitro screening of plant growth-promoting (PGP traits was carried out using eight Pseudomonas spp., PPR1 to PPR8, isolated from the rhizosphere of Phaseolus vulgaris growing on the Uttarakhand Himalayan range in India. All the isolates were fast growers, positive for catalase, oxidase and urease activities, and utilized lactose and some amino acids. All the isolates were indole acetic acid (IAA positive, however PPR8 solubilized potassium and zinc along with various other types of inorganic (tricalcium, dicalcium and zinc phosphate and organic (calcium phytate phosphates, as well as producing siderophore and ACC deaminase. PPR8 also produced cyanogens, extracellular chitinase, β-1,3-glucanase, β-1,4-glucanase and oxalate oxidase. Based on the PGP traits of all isolates, PPR8 was found to be the most potent plant growth-promoting rhizobacteria (PGPR. Further, PPR8 was identified as Pseudomonas sp. PPR8, based on 16S rRNA gene sequencing analysis. Moreover, the PGP activities of PPR8 confirmed it to be a potent biocontrol agent, inhibiting the growth of various plant pathogenic fungi. This study reveals the potential of Pseudomonas sp. PPR8 to be used as a good bioinoculant for growth promotion of common bean and for the protection of important legume crops from various deleterious phytopathogens.

  9. Ecofriendly biodegradation and detoxification of Reactive Red 2 textile dye by newly isolated Pseudomonas sp. SUK1.

    Science.gov (United States)

    Kalyani, D C; Telke, A A; Dhanve, R S; Jadhav, J P

    2009-04-30

    The aim of this work is to evaluate textile dyes degradation by novel bacterial strain isolated from the waste disposal sites of local textile industries. Detailed taxonomic studies identified the organisms as Pseudomonas species and designated as strain Pseudomonas sp. SUK1. The isolate was able to decolorize sulfonated azo dye (Reactive Red 2) in a wide range (up to 5 g l(-1)), at temperature 30 degrees C, and pH range 6.2-7.5 in static condition. This isolate also showed decolorization of the media containing a mixture of dyes. Measurements of COD were done at regular intervals to have an idea of mineralization, showing 52% reduction in the COD within 24h. Induction in the activity of lignin peroxidase and azoreductase was observed during decolorization of Reactive Red 2 in the batch culture, which represented their role in degradation. The biodegradation was monitored by UV-vis, IR spectroscopy, HPLC. The final product, 2-naphthol was characterized by GC-mass spectroscopy. The phytotoxicity study revealed the degradation of Reactive Red 2 into non-toxic product by Pseudomonas sp. SUK1.

  10. UO(2) 2+ speciation determines uranium toxicity and bioaccumulation in an environmental Pseudomonas sp. isolate.

    Science.gov (United States)

    Vanengelen, Michael R; Field, Erin K; Gerlach, Robin; Lee, Brady D; Apel, William A; Peyton, Brent M

    2010-04-01

    In the present study, experiments were performed to investigate how representative cellulosic breakdown products, when serving as growth substrates under aerobic conditions, affect hexavalent uranyl cation (UO(2) (2+)) toxicity and bioaccumulation within a Pseudomonas sp. isolate (designated isolate A). Isolate A taken from the Cold Test Pit South (CTPS) region of the Idaho National Laboratory (INL), Idaho Falls, ID, USA. The INL houses low-level uranium-contaminated cellulosic material and understanding how this material, and specifically its breakdown products, affect U-bacterial interactions is important for understanding UO(2) (2+) fate and mobility. Toxicity was modeled using a generalized Monod expression. Butyrate, dextrose, ethanol, and lactate served as growth substrates. The potential contribution of bicarbonate species present in high concentrations was also investigated and compared with toxicity and bioaccumulation patterns seen in low-bicarbonate conditions. Isolate A was significantly more sensitive to UO(2) (2+) and accumulated significantly more UO(2) (2+) in low-bicarbonate concentrations. In addition, UO(2) (2+) growth inhibition and bioaccumulation varied depending on the growth substrate. In the presence of high bicarbonate concentrations, sensitivity to UO(2) (2+) inhibition was greatly mitigated, and did not vary between the four substrates tested. The extent of UO(2) (2+) accumulation was also diminished. The observed patterns were related to UO(2) (2+) aqueous complexation, as predicted by MINTEQ (ver. 2.52) (Easton, PA, USA). In the low- bicarbonate medium, the presence of positively charged and unstable UO(2) (2+)-hydroxide complexes explained both the greater sensitivity of isolate A to UO(2) (2+), and the ability of isolate A to accumulate significant amounts of UO(2) (2+). The exclusive presence of negatively charged and stable UO(2) (2+)-carbonate complexes in the high bi-carbonate medium explained the diminished sensitivity of

  11. Legionella pneumophila persists within biofilms formed by Klebsiella pneumoniae, Flavobacterium sp., and Pseudomonas fluorescens under dynamic flow conditions.

    Directory of Open Access Journals (Sweden)

    Catherine R Stewart

    Full Text Available Legionella pneumophila, the agent of Legionnaires' disease pneumonia, is transmitted to humans following the inhalation of contaminated water droplets. In aquatic systems, L. pneumophila survives much of time within multi-organismal biofilms. Therefore, we examined the ability of L. pneumophila (clinical isolate 130 b to persist within biofilms formed by various types of aquatic bacteria, using a bioreactor with flow, steel surfaces, and low-nutrient conditions. L. pneumophila was able to intercalate into and persist within a biofilm formed by Klebsiella pneumoniae, Flavobacterium sp. or Pseudomonas fluorescens. The levels of L. pneumophila within these biofilms were as much as 4 × 10(4 CFU per cm(2 of steel coupon and lasted for at least 12 days. These data document that K. pneumoniae, Flavobacterium sp., and P. fluorescens can promote the presence of L. pneumophila in dynamic biofilms. In contrast to these results, L. pneumophila 130 b did not persist within a biofilm formed by Pseudomonas aeruginosa, confirming that some bacteria are permissive for Legionella colonization whereas others are antagonistic. In addition to colonizing certain mono-species biofilms, L. pneumophila 130 b persisted within a two-species biofilm formed by K. pneumoniae and Flavobacterium sp. Interestingly, the legionellae were also able to colonize a two-species biofilm formed by K. pneumoniae and P. aeruginosa, demonstrating that a species that is permissive for L. pneumophila can override the inhibitory effect(s of a non-permissive species.

  12. Inhibition of food-related bacteria by antibacterial substances produced by Pseudomonas sp. strains isolated from pasteurized milk

    Directory of Open Access Journals (Sweden)

    Ana Beatriz Ferreira Rangel

    2013-12-01

    Full Text Available In this work, the production of antimicrobial substances by strains of Pseudomonas sp. isolated from pasteurized milk and their potential action against food-related bacteria were investigated. Samples of pasteurized milk were purchased from arbitrarily chosen commercial establishments in the city of Rio de Janeiro, Brazil. Of the four samples analyzed, three presented several typical colonies of Pseudomonas. About 100 colonies were chosen and subjected to biochemical tests for confirmation of their identity. Eighteen strains of the Pseudomonas genus were identified and submitted to tests for the production of antimicrobial substances. Twelve strains (66.7% were identified as Pseudomonas fluorescens, four (22.2% as P. aeruginosa, one (5.5% as P. mendocina and one (5.5% as P. pseudoalcaligenes. Only two P. fluorescens strains were unable to produce any antimicrobial substance against any of the indicator strains tested. Most of the strains presented a broad spectrum of action, inhibiting reference and food-related strains such as Proteus vulgaris, Proteus mirabilis, Hafnia alvei, Yersinia enterocolitica, Escherichia coli and Salmonella typhi. Five antimicrobial substance-producing strains, which presented the broadest spectrum of action, were also tested against Staphylococcus aureus reference strains and 26 Staphylococcus sp. strains isolated from foods, some of which were resistant to antibiotics. The producer strains 8.1 and 8.3, both P. aeruginosa, were able to inhibit all the staphylococcal strains tested. The antimicrobial substances produced by strains 8.1 and 8.3 did not seem to be typical bacteriocins, since they were resistant to the three proteolytic enzymes tested. Experiments involving the characterization of these substances are being carried out in order to evaluate their biotechnological application.

  13. Medium Optimization for Enzymatic Production of L-Cysteine by Pseudomonas sp. Zjwp-14 Using Response Surface Methodology

    Directory of Open Access Journals (Sweden)

    Guo-Ying Lv

    2008-01-01

    Full Text Available Response surface methodology was applied to optimize medium constituents for enzymatic production of L-cysteine from DL-2-amino-Δ^2-thiazoline-4-carboxylic acid (DL-ATC by a novel Pseudomonas sp. Zjwp-14. With the Plackett-Burman design experiment, glycerol, DL-ATC, yeast extract, and pH were found to be the most powerful factors among the eight tested variables that influence intracellular enzyme activity for biotransformation of DL-ATC to L-cysteine. In order to investigate the quantitative effects for four variables selected from Plackett-Burman design on enzyme activity, a central composite design was subsequently employed for further optimization. The determination coefficient (R^2 was 0.9817, and the results show that the regression models adequately explain the data variation and represent the actual relationships between the parameters and responses. The optimal medium for Pseudomonas sp. Zjwp-14 was composed of (in g/L: glycerol 16.94, DL-ATC 4.59, yeast extract 6.99, NaCl 5.0, peptone 5.0, beef extract 5.0, MgSO4·7H2O 0.4, and pH=7.94. Under the optimal conditions, the maximum intracellular enzyme activity of 918.7 U/mL in theory and 903.6 U/mL in the experiment were obtained, with an increase of 15.6 % compared to the original medium components. In a 5-litre fermentor, cultivation time for Pseudomonas sp. Zjwp-14 was cut down for 6 h and the maximum enzyme activity reached 929.6 U/mL.

  14. Phosphatidylcholine synthesis is essential for HrpZ harpin secretion in plant pathogenic Pseudomonas syringae and non-pathogenic Pseudomonas sp. 593.

    Science.gov (United States)

    Xiong, Min; Long, Deliang; He, Huoguang; Li, Yang; Li, Yadong; Wang, Xingguo

    2014-01-01

    Pseudomonas syringae pv. syringae van Hall is important phytopathogenic bacterium of stone fruit trees, and able to elicit hypersensitive response (HR) in nonhost plants. The HrpZ, secreted via type III secretion system (T3SS) to the extracellular space of the plant, is a T3SS-dependent protein and a sole T3SS effector able to induce the host defense response outside host cells. We deleted the phosphatidylcholine synthase gene (pcs) of P. syringae pv. syringae van Hall CFCC 1336, and found that the 1336 pcs(-) mutant was unable to synthesize phosphatidylcholine and elicit a typical HR in soybean. Further studies showed that the 1336 pcs(-) mutant was unable to secrete HrpZ harpin but could express HrpZ protein in cytoplasm as effectively as the wild type. To confirm if phosphatidylcholine affects HrpZ harpin secretion, we introduced the hrpZ gene into the soil-dwelling bacterium Pseudomonas sp. 593 and the 593 pcs(-) mutant, which were unable to express HrpZ harpin and elicit HR in tobacco or soybean. Western blotting and HR assay showed that the 593H not only secreted HrpZ harpin but also caused a strong HR in tobacco and soybean. In contrast, the 593 pcs(-)H only expressed HrpZ protein in its cytoplasm at the wild type level, but did not secrete HrpZ harpin or elicit HR reaction. Our results demonstrate that phosphatidylcholine is essential for the secretion of HrpZ harpin in P. syringae pv. syringae van Hall and other Pseudomonas strains.

  15. Pyrroloquinoline Quinone-Dependent Cytochrome Reduction in Polyvinyl Alcohol-Degrading Pseudomonas sp. Strain VM15C

    OpenAIRE

    1989-01-01

    A polyvinyl alcohol (PVA) oxidase-deficient mutant of Pseudomonas sp. strain VM15C, strain ND1, was shown to possess PVA dehydrogenase, in which pyrroloquinoline quinone (PQQ) functions as a coenzyme. The mutant grew on PVA and required PQQ for utilization of PVA as an essential growth factor. Incubation of the membrane fraction of the mutant with PVA caused cytochrome reduction of the fraction. Furthermore, it was found that in spite of the presence of PVA oxidase, the membrane fraction of s...

  16. Pesticide tolerant and phosphorus solubilizing Pseudomonas sp. strain SGRAJ09 isolated from pesticides treated Achillea clavennae rhizosphere soil.

    Science.gov (United States)

    Rajasankar, R; Manju Gayathry, G; Sathiavelu, A; Ramalingam, C; Saravanan, V S

    2013-05-01

    In this study, an attempt was made to identify an effective phosphate solubilizing bacteria from pesticide polluted field soil. Based on the formation of solubilization halo on Pikovskaya's agar, six isolates were selected and screened for pesticide tolerance and phosphate (P) solubilization ability through liquid assay. The results showed that only one strain (SGRAJ09) obtained from Achillea clavennae was found to tolerate maximum level of the pesticides tested and it was phylogenetically identified as Pseudomonas sp. It possessed a wide range of pesticide tolerance, ranging from 117 μg mL(-1) for alphamethrin to 2,600 μg mL(-1) for endosulfan. The available P concentrations increased with the maximum and double the maximum dose of monocrotophos and imidacloprid, respectively. On subjected to FT-IR and HPLC analysis, the presence of organic acids functional group in the culture broth and the production of gluconic acid as dominant acid aiding the P solubilization were identified. On comparison with control broth, monocrotophos and imidacloprid added culture broth showed quantitatively high organic acids production. In addition to gluconic acid production, citric and acetic acids were also observed in the pesticide amended broth. Furthermore, the Pseudomonas sp. strain SGRAJ09 possessed all the plant growth promoting traits tested. In presence of monocrotophos and imidacloprid, its plant growth promoting activities were lower than that of the pesticides unamended treatment.

  17. Enhanced cometabolic degradation of methyl tert-butyl ether by a Pseudomonas sp. strain grown on n-pentane

    Science.gov (United States)

    Li, S. S.; Wang, S.; Yan, W.

    2016-08-01

    When methyl tert-butyl ether (MTBE) is added as oxygenates it increases the octane number and decreases the release of nitric oxide from the incomplete combustion of reformulated gasoline. The extensive use of MTBE allowed it to be detectable as a pollutant in both ground-level and underground water worldwide. The present study focuses on the isolation and characterization of MTB-degrading microorganisms by cometabolism based on the results of growth on different carbon sources. It also focuses on the kinetic analysis and the continuous degradation of MTBE. A bacterial strain WL1 that can grow on both n-alkanes (C5-C8) and aromatics was isolated and named Pseudomonas sp. WL1 according to the 16S rDNA sequencing analysis. Strain WL1 could cometabolically degrade MTBE in the presence of n-alkanes with a desirable degradation rate. Diverse n-alkanes with different lengths of carbon chains showed significant influence on the degradation rate of MTBE and accumulation of tert-butyl alcohol (TBA). When strain WL1 cometabolically degraded MTBE in the presence of n-pentane, higher MTBE-degrading rate and lower TBA-accumulation were observed (Vmax = 38.1 nmol/min/mgprotei, Ks = 6.8 mmol/L). In the continuous degrading experiment, the removal efficiency of MTBE by Pseudomonas sp. WL1 did not show any obvious decrease after five subsequent additions.

  18. The chitinase C gene PsChiC from Pseudomonas sp. and its synergistic effects on larvicidal activity

    Directory of Open Access Journals (Sweden)

    Wanfang Zhong

    2015-09-01

    Full Text Available Pseudomonas sp. strain TXG6-1, a chitinolytic gram-negative bacterium, was isolated from a vegetable field in Taixing city, Jiangsu Province, China. In this study, a Pseudomonas chitinase C gene (PsChiC was isolated from the chromosomal DNA of this bacterium using a pair of specific primers. The PsChiC gene consisted of an open reading frame of 1443 nucleotides and encoded 480 amino acid residues with a calculated molecular mass of 51.66 kDa. The deduced PsChiC amino acid sequence lacked a signal sequence and consisted of a glycoside hydrolase family 18 catalytic domain responsible for chitinase activity, a fibronectin type III-like domain (FLD and a C-terminal chitin-binding domain (ChBD. The amino acid sequence of PsChiCshowed high sequence homology (> 95% with chitinase C from Serratia marcescens. SDS-PAGE showed that the molecular mass of chitinase PsChiC was 52 kDa. Chitinase assays revealed that the chitobiosidase and endochitinase activities of PsChiCwere 51.6- and 84.1-fold higher than those of pET30a, respectively. Although PsChiC showed little insecticidal activity towards Spodoptera litura larvae, an insecticidal assay indicated that PsChiC increased the insecticidal toxicity of SpltNPV by 1.78-fold at 192 h and hastened death. These results suggest that PsChiC from Pseudomonas sp. could be useful in improving the pathogenicity of baculoviruses.

  19. Pseudomonas argentinensis sp. nov., a novel yellow pigment-producing bacterial species, isolated from rhizospheric soil in Cordoba, Argentina.

    Science.gov (United States)

    Peix, Alvaro; Berge, Odile; Rivas, Raúl; Abril, Adriana; Velázquez, Encarna

    2005-05-01

    During a study in the Argentinian region of Chaco (Cordoba), some strains were isolated from the rhizosphere of grasses growing in semi-desertic arid soils. Two of these strains, one isolated from the rhizospheric soil of Chloris ciliata (strain CH01(T)) and the other from Pappophorum caespitosum (strain PA01), were Gram-negative, strictly aerobic rods, which formed yellow round colonies on nutrient agar. They produced a water-insoluble yellow pigment, and a fluorescent pigment was also detected. A polyphasic taxonomic approach was used to characterize the strains. Comparison of the 16S rRNA gene sequences showed a similarity of 99.3 % between them, and phylogenetic analysis revealed that the strains belong to the genus Pseudomonas, within the gamma-subclass of the Proteobacteria. The closest related species is Pseudomonas straminea IAM 1598(T) (similarity of 99.0 % to strain CH01(T) and 98.8 % to strain PA01), clustering in a separate branch with the various methods of tree building used. Strains CH01(T) and PA01 both had a single polar flagellum, like other yellow pigment-producing pseudomonads related to them. Both strains produced catalase and oxidase. Similar to P. straminea, they did not hydrolyse gelatin or casein. The G+C DNA contents determined were 57.5 mol% for CH01(T) and 58.0 mol% for PA01. DNA-DNA hybridization results showed 81 % relatedness between them, and only 40-44 % relatedness with respect to the type strain of P. straminea. These results, together with other phenotypic characteristics, support the conclusion that both isolates belong to the same species, and should be described as representing a novel species within the genus Pseudomonas, for which the name Pseudomonas argentinensis sp. nov. is proposed. The type strain is CH01(T) (=LMG 22563(T) = CECT 7010(T)).

  20. The Construction of Recombinant Strain Pseudomonas sp.B4 and the Optimization of Fermentation Conditions%基因工程菌Pseudomonas sp.B4的构建及其产邻苯二酚发酵条件的初步研究

    Institute of Scientific and Technical Information of China (English)

    唐咸来; 熊建文; 梁璇; 申佩弘; 武波

    2008-01-01

    利用PCR技术以Pseudomonas sp. B3-1基因组DNA为模板,扩增出2.9kb编码苯甲酸双加氧酶基因簇benABC.将该基因簇连接于pLAFRJ载体,电转化至E.coli DH5α,再通过三亲本结合法导入野生菌株Pseudomonas sp. B3-1中,得到了一株邻苯二酚产量提高的基因工程菌,命名为Pseudomonas sp.B4,在相同发酵条件下,工程菌Pseudomonas sp.B4的邻苯二酚产量达到0.5mg/ml,比野生菌株Pseudomonas sp. B3-1提高了17.5%.对工程菌Pseudomonas sp.B4进行发酵条件优化表明,当苯甲酸钠浓度为6.0 g/L,聚蛋白胨浓度为2.5 g/L,温度为32℃以及pH值为6.0时,工程菌在200r/min旋转摇床发酵36小时后,邻苯二酚产量达到0.7 mg/ml,比野生菌株Pseudomonas sp. B3-1提高了75%.

  1. Pseudomonas chloritidismutans sp. nov., a non-denitrifying chlorate-reducing bacterium

    NARCIS (Netherlands)

    Wolterink, A.F.W.M.; Jonker, A.B.; Kengen, S.W.M.; Stams, A.J.M.

    2002-01-01

    A Gram-negative, facultatively anaerobic, rod-shaped, dissimilatory chlorate-reducing bacterium, strain AW-1(T), was isolated from biomass of an anaerobic chlorate-reducing bioreactor. Phylogenetic analysis of the 16S rDNA sequence showed 100␜equence similarity to Pseudomonas stutzeri DSM 50227 and

  2. GILL-ROT DISEASE OF EUROPEAN EEL INFECTED BY PSEUDOMONAS SP.%Pseudomonas sp. 引起欧洲鳗鲡烂鳃病的初步研究

    Institute of Scientific and Technical Information of China (English)

    樊海平; 曾占壮; 余培建; 李志青

    2001-01-01

    @@欧洲鳗鲡[Anguilla anguilla(L.)] 养殖过程中,细菌性疾病危害严重,其中烂鳃病周年发生且发病率高。欧洲鳗烂鳃病常与寄生虫病、真菌病并发,因而给治疗带来了困难。鳗鲡烂鳃病病原主要有柱状屈桡杆菌、噬纤维菌等[1—3]。本文报告由Pseudomonas sp. 引起的欧洲鳗鲡烂鳃病。

  3. Role of phenazines and cyclic lipopeptides produced by pseudomonas sp. CMR12a in induced systemic resistance on rice and bean.

    Science.gov (United States)

    Ma, Zongwang; Hua, Gia Khuong Hoang; Ongena, Marc; Höfte, Monica

    2016-08-25

    Pseudomonas sp. CMR12a produces two different classes of cyclic lipopeptides (CLPs) (orfamides and sessilins), which all play a role in direct antagonism against soilborne pathogens. Here we show that Pseudomonas sp. CMR12a is also able to induce systemic resistance to Magnaporthe oryzae on rice and to the web blight pathogen Rhizoctonia solani AG2-2 on bean. Plant assays with biosynthesis mutants of Pseudomonas sp. CMR12a impaired in the production of phenazines and/or CLPs and purified metabolites revealed that distinct bacterial determinants are responsible for inducing systemic resistance in these two pathosystems. In rice, mutants impaired in phenazine production completely lost their ability to induce systemic resistance, while a soil drench with pure phenazine-1-carboxamide (PCN) at a concentration of 0.1 or 1 μM was active in inducing resistance against M. oryzae. In bean, mutants that only produced phenazines, sessilins or orfamides were still able to induce systemic resistance against Rhizoctonia web blight, but a balanced production of these metabolites was needed. This study not only shows that Pseudomonas sp. CMR12a can protect rice to blast disease and bean to web blight disease, but also displays that the determinants involved in induced systemic resistance are plant, pathogen and concentration dependent.

  4. Draft Genome Sequence of Pseudomonas sp. BDAL1 Reconstructed from a Bakken Shale Hydraulic Fracturing-Produced Water Storage Tank Metagenome

    Energy Technology Data Exchange (ETDEWEB)

    Lipus, Daniel; Ross, Daniel; Bibby, Kyle; Gulliver, Djuna

    2017-03-16

    ABSTRACT

    We report the 5,425,832 bp draft genome ofPseudomonassp. strain BDAL1, recovered from a Bakken shale hydraulic fracturing-produced water tank metagenome. Genome annotation revealed several key biofilm formation genes and osmotic stress response mechanisms necessary for survival in hydraulic fracturing-produced water.

  5. Decolorization of adsorbed textile dyes by developed consortium of Pseudomonas sp. SUK1 and Aspergillus ochraceus NCIM-1146 under solid state fermentation.

    Science.gov (United States)

    Kadam, Avinash A; Telke, Amar A; Jagtap, Sujit S; Govindwar, Sanjay P

    2011-05-15

    The objective of this study was to develop consortium using Pseudomonas sp. SUK1 and Aspergillus ochraceus NCIM-1146 to decolorize adsorbed dyes from textile effluent wastewater under solid state fermentation. Among various agricultural wastes rice bran showed dye adsorption up to 90, 62 and 80% from textile dye reactive navy blue HE2R (RNB HE2R) solution, mixture of textile dyes and textile industry wastewater, respectively. Pseudomonas sp. SUK1 and A. ochraceus NCIM-1146 showed 62 and 38% decolorization of RNB HE2R adsorbed on rice bran in 24h under solid state fermentation. However, the consortium of Pseudomonas sp. SUK1 and A. ochraceus NCIM-1146 (consortium-PA) showed 80% decolorization in 24h. The consortium-PA showed effective ADMI removal ratio of adsorbed dyes from textile industry wastewater (77%), mixture of textile dyes (82%) and chemical precipitate of textile dye effluent (CPTDE) (86%). Secretion of extracellular enzymes such as laccase, azoreductase, tyrosinase and NADH-DCIP reductase and their significant induction in the presence of adsorbed dye suggests their role in the decolorization of RNB HE2R. GCMS and HPLC analysis of product suggests the different fates of biodegradation of RNB HE2R when used Pseudomonas sp. SUK1, A. ochraceus NCIM-1146 and consortium PA.

  6. Genome Sequence of Pseudomonas sp. Strain Chol1, a Model Organism for the Degradation of Bile Salts and Other Steroid Compounds

    KAUST Repository

    Holert, Johannes

    2013-01-15

    Bacterial degradation of steroid compounds is of high ecological and biotechnological relevance. Pseudomonas sp. strain Chol1 is a model organism for studying the degradation of the steroid compound cholate. Its draft genome sequence is presented and reveals one gene cluster responsible for the metabolism of steroid compounds.

  7. Draft Genome Sequence of Pseudomonas sp. EpS/L25, Isolated from the Medicinal Plant Echinacea purpurea and Able To Synthesize Antimicrobial Compounds

    Science.gov (United States)

    Presta, Luana; Bosi, Emanuele; Fondi, Marco; Maida, Isabel; Perrin, Elena; Miceli, Elisangela; Maggini, Valentina; Bogani, Patrizia; Firenzuoli, Fabio; Di Pilato, Vincenzo; Rossolini, Gian Maria; Mengoni, Alessio

    2016-01-01

    We announce here the draft genome sequence of Pseudomonas sp. strain EpS/L25, isolated from the stem/leaves of the medicinal plant Echinacea purpurea. This genome will allow for comparative genomics in order to identify genes associated with the production of bioactive compounds and antibiotic resistance. PMID:27151804

  8. Metabolism of 2,2'-dihydroxybiphenyl by Pseudomonas sp. strain HBP1 : production and consumption of 2,2',3-trihydroxybiphenyl

    NARCIS (Netherlands)

    Kohler, Hans-Peter E.; Schmid, Andreas; Maarel, Marc van der

    1993-01-01

    Cells of Pseudomonas sp. strain HBP1 grown on 2-hydroxy- or 2,2'-dihydroxybiphenyl contain NADH-dependent monooxygenase activity that hydroxylates 2,2'-dihydroxybiphenyl. The product of this reaction was identified as 2,2',3-trihydroxybiphenyl by 1H nuclear magnetic resonance and mass spectrometry.

  9. Biodegradation of biphenyl and removal of 2-chlorobiphenyl by Pseudomonas sp. KM-04 isolated from PCBs-contaminated mine impacted soil

    Science.gov (United States)

    Nam, I.; Chon, C.; Kim, J.; Kim, Y.

    2013-12-01

    The aim of the present study is to remediate the PCBs contaminated mine soil using microcosm study. For that, the naturally occurring microorganisms are stimulated and enriched in soil itself by supplementing biphenyl as well as benzoic acid. As a result the biphenyl degrading organisms are induced to degrade the PCBs contamination. From the stimulated soil, the biphenyl degrading organisms are isolated and degraded metabolites are elucidated. Pseudomonas sp. strain KM-04 was isolated from PCBs-contaminated soil in a coal mine-impacted area, and identification of bacteria was done by sequencing the 16S rRNA gene analysis. The growth of Pseudomonas sp. strain KM-04 using biphenyl as the sole carbon source was investigated by culturing in 100-mL Erlenmeyer flasks containing 10 ml sterilized MSM and 10 μg/ml biphenyl, and the ability of KM-04 to remove biphenyl and 2-chlorobiphenyl from mine soil was investigated. Metabolite formation was confirmed by liquid chromatography/atmospheric pressure chemical ionization-mass spectrometric analysis. Pseudomonas sp. strain KM-04 uses biphenyl as a sole carbon and energy source, and resting cells convert biphenyl to its metabolic intermediates, including dihydroxybiphenyl, 2-hydroxy-6-oxo-6-phenylhexa-2,4-dienoic acid, and benzoic acid. Incubation of real soil collected from abandoned mine areas with resting cells of Pseudomonas sp. strain KM-04 for 10 days resulted in the 98.5 % of biphenyl and 82.3 % of 2-chlorobiphenyl in a slurry system. The ability of the Pseudomonas sp. strain KM-04 to bioremediate biphenyl and 2-chlorobiphenyl from abandoned mine soil was examined using soil microcosm studies under laboratory conditions. Treatment of mine soil with the Pseudomonas sp. strain KM-04 for 15 days resulted in 87.1 % reduction in biphenyl and 68.7 % in 2-chlorobiphenyl contents. The results suggest that Pseudomonas sp. strain KM-04 is a potential candidate for the biological removal of biphenyl and chlorinated derivatives

  10. A sirA-like gene, sirA2, is essential for 3-succinoyl-pyridine metabolism in the newly isolated nicotine-degrading Pseudomonas sp. HZN6 strain.

    Science.gov (United States)

    Qiu, Jiguo; Ma, Yun; Chen, Liansheng; Wu, Lifei; Wen, Yuezhong; Liu, Weiping

    2011-12-01

    A novel nicotine-degrading Pseudomonas sp. strain, HZN6, was isolated from a pesticide-wastewater treatment facility in Hangzhou. The strain could grow on nicotine as its sole source of carbon, nitrogen, and energy. The strain's main intermediate metabolites were determined to be pseudooxynicotine, 3-succinoyl-pyridine (SP), and 6-hydroxy-3-succinoyl-pyridine (HSP). A Tn5 transposon mutant was generated in which the degradation pathway was blocked at the SP. A 4,583-bp DNA fragment flanking the transposon insertion site was obtained through self-formed adaptor PCR and analyzed. The mutant gene orfC displays 89% deduced amino acid sequence identity with the sirA-like gene (sirA2, a sulfurtransferase homologue gene) of Pseudomonas stutzeri A1501. The orfC-disrupted strain lost the ability to degrade SP, and the complementation strains with the orfC from the Pseudomonas sp. HZN6 and the sirA2 (PP_1233) from Pseudomonas putida KT2440 recovered the degradation ability. Though the orfC-disrupted strain also lost the xanthine dehydrogenase activity, the effects of tungsten on the degradation of SP and hypoxanthine revealed that the hydroxylation of SP to HSP was not a xanthine dehydrogenase type. These results demonstrated that the orfC gene was essential for the SP metabolism involved in the nicotine metabolic pathway in the Pseudomonas sp. HZN6 strain. This study might advance the understanding of the nicotine metabolic mechanism in Pseudomonas.

  11. Estudo da capacidade de sorção de cobre por Pseudomonas putida sp. em reator.

    OpenAIRE

    2014-01-01

    Bactérias aclimatadas a cobre foram isoladas a partir de amostras de solo e água coletadas na região da Mina de Sossego (Vale, Carajás, PA). Pseudomonas putida sp. foi escolhida, pois, apresentou a maior capacidade sortiva de Cu2+, Q = 40 mg/g. O cultivo em regime de batelada, meio mineral, com glicerol como fonte de carbono, resultou fator de conversão de glicerol a células, YX/S, de 0,49 g/g e velocidade específica máxima de crescimento, mmax, de 0,11 h-1. Alta concentração celular, 90 g/L,...

  12. Cloning and Sequence Analysis of a Novel Cold-Adapted Lipase Gene from Strain Iip35 (Pseudomonas sp.)

    Institute of Scientific and Technical Information of China (English)

    WANG Cai-hong; GUO Run-fang; YU Hong-wei; JIA Ying-min

    2008-01-01

    A combination method of the usual-PCR and reverse-PCR for the cloning of a novel lipase gene directly from the total genomic DNA of strain lip35 (Pseudomonas sp.) is described, whereby a lipase gene (lip) was cloned directly from genomic DNA. The sequence data have been deposited in the GenBank and EMBL data bank with the accession number EU414288. The nucleotide sequence showed a major open reading frame encoding a 59-kDa protein of 566 amino acid residues, which contained a lipase consensus sequence GXSXG. The lipase lip had 74 and 70% homologies with the Upases of an uncultured bacterium and P.fluorescens PfO-1, respectively, but it did not show any overall homology with lipases from other origins. The functional lipase was obtained when the lip gene was expressed in Pichia pastoris GS115.

  13. Differentiating Pseudomonas sp. strain ADP cells in suspensions and biofilms using Raman spectroscopy and scanning electron microscopy.

    Science.gov (United States)

    Henry, Victoria A; Jessop, Julie L P; Peeples, Tonya L

    2017-02-01

    High quality spectra of Pseudomonas sp. strain ADP in the planktonic and biofilm state were obtained using Raman microspectroscopy. These spectra enabled the identification of key differences between free and biofilm cells in the fingerprint region of Raman spectra in the nucleic acid, carbohydrate, and protein regions. Scanning electron microscopy (SEM) enabled detailed visualization of ADP biofilm with confirmation of associated extracellular matrix structure. Following extraction and Raman analysis of extracellular polymeric substances, Raman spectral differences between free and biofilm cells were largely attributed to the contribution of extracellular matrix components produced in mature biofilms. Raman spectroscopy complemented with SEM proves to be useful in distinguishing physiological properties among cells of the same species. Graphical Abstract Raman spectroscopy complemented with SEM proves to be useful in distinguishing physiological properties among cells of the same species.

  14. Gas Chromatography - Mass Spectrometry Analysis and Antibacterial Activity of Bluish-Green Pigment from Pseudomonas sp. JJTBVK (KF836502

    Directory of Open Access Journals (Sweden)

    Bala Verma

    2015-08-01

    Full Text Available The present study was conducted for the isolation of potential bacteria from the desert soil, their molecular identification and prediction of restriction sites of the potential isolate using the bioinformatics tools. Production of the metabolites was done by inoculating in nutrient broth of pH 8.6. Metabolite was bluish-green in color; it was extracted and dried by using methanol and used for partial characterization by using GC-MS spectroscopy. Antibacterial activity was performed with the clinical human pathogenic isolates. The bacterium was identified as Pseudomonas sp.JJTBVK on the basis of 16S rRNA sequencing. The sequence was analyzed for the restriction cleavage sites, which showed that the sequence had various restriction sites for different enzymes. Antibacterial activity (MIC of methanol extract of the bacterial culture broth showed antibacterial activity (MIC, which was 29, 30, 30 and 29 mm for Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus subtilis and Salmonella typhi, respectively. GC-MS analysis of the methanol extract showed the presence of naphth [2,3-B] azet-2 (1H -one, 1-phenyl-, which was the characteristic compound showing the antibacterial activity.

  15. Increased concentration of Pseudomonas aeruginosa and Staphylococcus sp. in small animals exposed to aerospace environments

    Science.gov (United States)

    Guthrie, R. K.

    1976-01-01

    The effects of increased concentrations of PSEUDOMONAS AERUGINOSA AND STAPHYLOCOCCUS in the total bacterial flora of small animals exposed to simulated spacecraft environments were evaluated. Tests to detect changes in infectivity, effects of antibiotic treatments, immune responses to bacterial antigens, and effectiveness of immune responses in the experimental environment were conducted. The most significant results appear to be the differences in immune responses at simulated altitudes and the production of infection in the presence of a specific antibody.

  16. Pesquisa de Acinetobacter sp e Pseudomonas aeruginosa produtores de metalo-β-lactamase em hospital de emergência de Porto Alegre, Estado do Rio Grande do Sul, Brasil Investigation of metallo-β-lactamase-producing Acinetobacter sp and Pseudomonas aeruginosa at an emergency hospital in Porto Alegre, State of Rio Grande do Sul, Brazil

    Directory of Open Access Journals (Sweden)

    Vani Dos Santos Laranjeira

    2010-08-01

    Full Text Available INTRODUÇÃO: O aparecimento de Pseudomonas aeruginosa e Acinetobacter sp produtores de metalo-β-lactamases (MBLs é um desafio para os hospitais. MÉTODOS: Verificou-se a produção de MBL em cepas clínicas de Pseudomonas aeruginosa e Acinetobacter sp de um hospital de emergência de Porto Alegre pelo método de aproximação de disco e E-test MBL. Os genes bla foram pesquisados pela PCR. RESULTADOS: Duas cepas de Pseudomonas aeruginosa e oito Acinetobacter sp demonstraram fenótipo de MBLs. A amplificação do gene blaSPM-1 confirmou a enzima em P. aeruginosa.. CONCLUSÕES: Deve-se ter cautela ao avaliar testes fenotípicos utilizados na detecção rotineira de metalo-enzima.INTRODUCTION: The appearance of metallo-β-lactamase (MBL-producing Pseudomonas aeruginosa and Acinetobacter sp. is a challenge for hospitals. METHODS: The production of MBL in clinical isolates of Pseudomonas aeruginosa and Acinetobacter sp. From an emergency hospital in Porto Alegre was investigated using the disk approximation test and MBL E-test. The bla genes were determined using PCR. RESULTS: Two strains of Pseudomonas aeruginosa and eight of Acinetobacter sp were shown to be MBL phenotypes. Amplification of the blaSPM-1 gene confirmed the presence of the enzyme in P. aeruginosa. CONCLUSIONS: Caution is needed in evaluating phenotype tests used for routine detection of metallo-β-lactamases.

  17. Microbial degradation of pyridine using Pseudomonas sp. and isolation of plasmid responsible for degradation.

    Science.gov (United States)

    Mohan, S Venkata; Sistla, Srinivas; Guru, R Kumar; Prasad, K Krishna; Kumar, C Suresh; Ramakrishna, S V; Sarma, P N

    2003-01-01

    Pseudomonas (PI2) capable of degrading pyridine was isolated from the mixed population of the activated sludge unit which was being used for treating complex effluents, the strain was characterized. Aerobic degradation of pyridine was studied with the isolated strain and the growth parameters were evaluated. Pyridine degradation was further conformed by chromatography (HPLC) analysis. The process parameters like biomass growth and dissolved oxygen consumption were monitored during pyridine degradation. In order to conform with the plasmid capability to degrade pyridine, the requisite plasmid was isolated and transferred to DH 5alpha Escherichia coli. The subsequent biodegradation studies revealed the ability of the transformed plasmid capability to degrade the pyridine.

  18. Evidence of aerobic utilization of di-ortho-substituted trichlorobiphenyls as growth substrates by Pseudomonas sp. SA-6 and Ralstonia sp. SA-4.

    Science.gov (United States)

    Adebusoye, Sunday A; Picardal, Flynn W; Ilori, Matthew O; Amund, Olukayode O

    2008-05-01

    Robust and effective bioremediation strategies have not yet been developed for polychlorinated biphenyl (PCB)-contaminated soils. This is in part a result of the fact that ortho- or ortho- and para-substituted congeners, frequent dead-end products of reductive dechlorination of PCB mixtures, have greatly reduced aerobic biodegradability. In this study, we report substantial evidence of utilization of diortho-substituted trichlorobiphenyls (triCBs) as growth substrates by Ralstonia sp. SA-4 and Pseudomonas sp. SA-6 in which ortho-substitution resulted in no obvious patterns of recalcitrance. These stains exhibited unusual preferences for growth on congeners chlorinated on both rings. Substrate uptake studies with benzoate-grown cells revealed that the isolates attacked the 2-chlorophenyl rings of 2,2',4- and 2,2',5-triCB. Between 71% and 93% of the initial 0.23-0.34 mM dose of congeners were transformed in less than 261 h concomitant with non-stoichiometric production of respective dichlorobenzoates and chloride ion. In enzyme assays, activity of 2,3-dihydroxybiphenyl-1,2-dioxygenase was constitutive. Additionally, these strains harboured no detectable plasmids which, coupled with exponential growth on the two triCB congeners, suggested chromosomal location of PCB degradative genes. In addition to the fact that there is a paucity of information on degradation of PCBs by tropical isolates, growth on triCBs as a sole carbon and energy source has never been demonstrated for any natural or engineered microorganisms. Such isolates may help prevent accumulation of ortho-substituted congeners in natural systems and offer the hope for development of effective bioaugmentation or sequential anaerobic-aerobic bioremediation strategies.

  19. Degradation of polycyclic aromatic hydrocarbons by Pseudomonas sp.JM2 isolated from active sewage sludge of chemical plant

    Institute of Scientific and Technical Information of China (English)

    Jing Ma; Li Xu; Lingyun Jia

    2012-01-01

    It is important to screen strains that can decompose polycyclic aromatic hydrocarbons (PAHs) completely and rapidly with good adaptability for bioremediation in a local area.A bacterial strain JM2,which uses phenanthrene as its sole carbon source,was isolated from the active sewage sludge from a chemical plant in Jilin,China and identified as Pseudomonas based on 16S rDNA gene sequence analysis.Although the optimal growth conditions were determined to be pH 6.0 and 37℃,JM2 showed a broad pH and temperature profile.At pH 4.5 and 9.3,JM2 could degrade more than 40% of fluorene and phenanthrene (50 mg/L each) within 4 days.In addition,when the temperature was as low as 4℃,JM2 could degrade up to 24% fluorene and 12% phenanthrene.This showed the potential for JM2 to be applied in bioremediation over winter or in cold regions.Moreover,a nutrient augmentation study showed that adding formate into media could promote PAH degradation,while the supplement of salicylate had an inhibitive effect.Furthermore,in a metabolic pathway study,salicylate,phthaiic acid,and 9-fluorenone were detected during the degradation of fluorene or phenanthrene.In conclusion,Pseudomonas sp.JM2 is a high performance strain in the degradation of fluorene and phenanthrene under extreme pH and temperature conditions.It might be useful in the bioremediation of PAHs.

  20. Determining design and scale-up parameters for degradation of atrazine with suspended Pseudomonas sp. ADP in aqueous bioreactors.

    Science.gov (United States)

    Biglione, Nicole; Rodgers, V G J; Peeples, Tonya L

    2008-01-01

    This work investigated the kinetic parameters of atrazine mineralization by suspended cells of Pseudomonas sp. ADP in both shake flasks and spherical stirred tank batch reactors (SSTR). The degradation of atrazine and growth of Pseudomonas sp. ADP were studied. Experiments were performed at different temperatures and stirring speeds in both reactors at varying initial concentrations of atrazine. Cell growth and atrazine concentration were monitored over time, and a Monod model with one limiting substrate was used to characterize the kinetic behavior. Temperature, stirring speed, and reactor type were all found to significantly affect the regressed Monod parameters. At 27 degrees C and 200 rpm, for the shaker flask experiments, mu max and Ks were determined to be 0.14 (+/-0.01) h-1 and 1.88 (+/-1.80) mg/L, respectively. At 37 degrees C, mu max and Ks increased to 0.25 (+/-0.05) h-1 and 9.59 (+/-6.55) mg/L, respectively. As expected, stirrer speed was also found to significantly alter the kinetic parameters. At 27 degrees C and 125 rpm, mu max and Ks were 0.04 (+/-0.002) h-1 and 3.72 (+/-1.05) mg/L, respectively, whereas at 37 degrees C and 125 rpm, mu max and Ks were 0.07 (+/-0.008) h-1 and 1.65 (+/-2.06) mg/L. In the SSTR the kinetic parameters mu max and Ks at room temperature were determined to be 0.12 (+/-0.009) h-1 and 2.18 (+/-0.47) mg/L, respectively. Although the mu max values for both types of reactors were similar, the shaker flask experiments resulted in considerable error. Error analysis on calculated values of Ks were found to impact estimates in atrazine concentration by as much as two orders of magnitude, depending on the reactor design, illustrating the importance of these factors in reactor scale-up.

  1. Conclusion on the peer review of the pesticide risk assessment of the active substance Pseudomonas sp. strain DSMZ 13134

    Directory of Open Access Journals (Sweden)

    European Food Safety Authority

    2012-12-01

    Full Text Available The conclusions of the European Food Safety Authority (EFSA following the peer review of the initial risk assessments carried out by the competent authority of the rapporteur Member State the Netherlands, for the pesticide active substance Pseudomonas sp. strain DSMZ 13134 are reported. The context of the peer review was that required by Commission Regulation (EU No 188/2011. The conclusions were reached on the basis of the evaluation of the representative uses of Pseudomonas sp. strain DSMZ 13134 as a fungicide on seed potatoes, flowers, tomatoes, cucumbers, peppers, eggplant, lettuce and cabbage. The reliable endpoints concluded as being appropriate for use in regulatory risk assessment, derived from the available studies and literature in the dossier peer reviewed, are presented. Missing information identified as being required by the regulatory framework is listed. Concerns are identified.

  2. Draft Genome Sequence of Pseudomonas sp. Strain BMS12, a Plant Growth-Promoting and Protease-Producing Bacterium, Isolated from the Rhizosphere Sediment of Phragmites karka of Chilika Lake, India.

    Science.gov (United States)

    Mishra, Samir R; Panda, Ananta Narayan; Ray, Lopamudra; Sahu, Neha; Mishra, Gayatri; Jadhao, Sudhir; Suar, Mrutyunjay; Adhya, Tapan Kumar; Rastogi, Gurdeep; Pattnaik, Ajit Kumar; Raina, Vishakha

    2016-06-30

    We report the 4.51 Mb draft genome of Pseudomonas sp. strain BMS12, a Gram-negative bacterium in the class of Gammaproteobacteria, isolated from the rhizospheric sediment of Phragmites karka, an invasive weed in Chilika Lake, Odisha, India. The Pseudomonas sp. strain BMS12 is capable of producing proteases and is also an efficient plant growth promoter that can be useful for various phytoremedial and industrial applications.

  3. Characterization of a marine-isolated mercury-resistant Pseudomonas putida strain SP1 and its potential application in marine mercury reduction

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Weiwei; Chen, Lingxin; Liu, Dongyan [Chinese Academy of Sciences, Yantai, SD (China). Yantai Inst. of Coastal Zone Research (YICCAS); Chinese Academy of Sciences, Yantai, SD (China). Shandong Provincial Key Lab. of Coastal Zone Environmental Processes

    2012-02-15

    The Pseudomonas putida strain SP1 was isolated from marine environment and was found to be resistant to 280 {mu}M HgCl{sub 2}. SP1 was also highly resistant to other metals, including CdCl{sub 2}, CoCl{sub 2}, CrCl{sub 3}, CuCl{sub 2}, PbCl{sub 2}, and ZnSO{sub 4}, and the antibiotics ampicillin (Ap), kanamycin (Kn), chloramphenicol (Cm), and tetracycline (Tc). mer operon, possessed by most mercury-resistant bacteria, and other diverse types of resistant determinants were all located on the bacterial chromosome. Cold vapor atomic absorption spectrometry and a volatilization test indicated that the isolated P. putida SP1 was able to volatilize almost 100% of the total mercury it was exposed to and could potentially be used for bioremediation in marine environments. The optimal pH for the growth of P. putida SP1 in the presence of HgCl{sub 2} and the removal of HgCl{sub 2} by P. putida SP1 was between 8.0 and 9.0, whereas the optimal pH for the expression of merA, the mercuric reductase enzyme in mer operon that reduces reactive Hg{sup 2+} to volatile and relatively inert monoatomic Hg{sup 0} vapor, was around 5.0. LD50 of P. putida SP1 to flounder and turbot was 1.5 x 10{sup 9} CFU. Biofilm developed by P. putida SP1 was 1- to 3-fold lower than biofilm developed by an aquatic pathogen Pseudomonas fluorescens TSS. The results of this study indicate that P. putida SP1 is a low virulence strain that can potentially be applied in the bioremediation of HgCl{sub 2} contamination over a broad range of pH. (orig.)

  4. Bioprospecting of marine Streptomycetes sp. for its antagonistic activity on MDR Pseudomonas aeruginosa and Acinetobacter baumannii isolates

    Directory of Open Access Journals (Sweden)

    Shanthi John

    2014-02-01

    Full Text Available Objective: To assess the antimicrobial activity of the Actinobacteria bioactive secondary metabolite and characterize the drug resistance mechanisms of Pseudomonas aeruginosa (P. aeruginosa and Acinetobacter baumannii (A. baumannii. Methods: Potential marine Actinobacteria were isolated and the crude extract was purified using thin layer chromatography, the fractions were tested for antimicrobial activity and phylogeny of the selected strain was analyzed. Isolated pathogenic strains were screened for extended spectrum beta-lactamase, mannan-binding lectin, AmpC production, efflux mechanism and polymerase chain reaction. The cephalosporin and carbapenem antibiotics were synergistically tested along with Streptomyces sp. PM49 fraction by combination disc test and double-disc synergy test. Heterogeneous susceptibility assay, minimum inhibitory concentration and expression of DnaK (Hsp70 were determined. Results: Streptomyces sp. PM49 active fraction of Rfvalue 0.69 showed antimicrobial activity and an inhibitory zone of 15 to 7 mm obtained. About 34.1% of P. aeruginosa and 4.8% of A. baumannii were multiple drug resistant. AmpC β-lactamase was found in 12% of A. baumannii, efflux mechanism was putatively positive in 8/23 of P. aeruginosa and 3/20 of A. baumannii. Combination disc test and double-disc synergy test with both PM49 compound and antibiotics showed an increase in the inhibitory zone of <3 mm to 4 mm, three P. aeruginosa isolates expressed blaIMP. Heteroresistant subcolonies grew at a frequency of 3 ×10-5 to 1 ×10-5. Stress induction analysis showed increase of DnaK during heat shock at 52 °C, the levels of protein doubled after exposure to the antibiotics. Conclusions: Novel unexplored Streptomyces spp. antimicrobial constituents can be developed as an inhibitor and can be substituted along with the available antibiotics to combat the drug resistant pathogens.

  5. Biosynthesis of indigo dye by newly isolated naphthalene-degrading strain Pseudomonas sp. HOB1 and its application in dyeing cotton fabric.

    Science.gov (United States)

    Pathak, Hilor; Madamwar, Datta

    2010-03-01

    Indigo is one of the oldest dyes manufactured chemically and is mostly used in textile, food, and pharmaceutical industries. However, owing to the environmental hazards posed by the chemical production, the present scenario in the field stipulates a biosynthesis alternative for indigo production. The present study describes an indigenously isolated naphthalene-degrading strain Pseudomonas sp. HOB1 producing a blue pigment when indole was added in the growth medium. This blue pigment was analyzed by high-pressure thin-layer chromatography and other spectroscopic techniques which revealed it to be the indigo dye. Pseudomonas sp. HOB1 showed ability to produce 246 mg indigo liter(-1) of the medium. The K (m) for the enzyme naphthalene dioxygenase which is involved in indigo formation is 0.3 mM, and V (max) was as high as 50 nmol min(-1) mg dry biomass(-1). The bacterial indigo dye was further successfully applied for dyeing cotton fabrics. The high indigo productivity of Pseudomonas sp. HOB1 using naphthalene as growth substrate and its applicability on cotton fabrics, therefore, stems the probability of using this culture for commercial indigo production.

  6. Significant reduction in toxicity, BOD, and COD of textile dyes and textile industry effluent by a novel bacterium Pseudomonas sp. LBC1.

    Science.gov (United States)

    Telke, Amar A; Kim, Seon-Won; Govindwar, Sanjay P

    2012-03-01

    The 16S rRNA sequence analysis and biochemical characteristics were confirmed that the isolated bacterium is Pseudomonas sp. LBC1. The commonly used textile dye, Direct Brown MR has been used to study the fate of biodegradation. Pseudomonas sp. LBC1 showed 90% decolorization of Direct Brown MR (100 mg/L) and textile industry effluent with significant reduction in COD and BOD. The optimum condition for decolorization was 7.0 pH and 40°C. Significant increase in a activity of extracellular laccase suggested their possible involvement in decolorization of Direct Brown MR. Biodegradation metabolites viz. 3,6-dihydroxy benzoic acid, 2-hydroxy-7-aminonaphthol-3-sulfonic acid, and p-dihydroperoxybenzene were identified on the basis of mass spectra and using the 1.10 beta Shimadzu NIST GC-MS library. The Direct Brown MR and textile industry effluent were toxic to Sorghum bicolor and Vigna radiata plants as compared to metabolites obtained after decolorization. The Pseudomonas sp. LBC1 could be useful strain for decolorization and detoxification of textile dyes as well as textile industry effluent.

  7. Use of silica-encapsulated Pseudomonas sp. strain NCIB 9816-4 in biodegradation of novel hydrocarbon ring structures found in hydraulic fracturing waters.

    Science.gov (United States)

    Aukema, Kelly G; Kasinkas, Lisa; Aksan, Alptekin; Wackett, Lawrence P

    2014-08-01

    The most problematic hydrocarbons in hydraulic fracturing (fracking) wastewaters consist of fused, isolated, bridged, and spiro ring systems, and ring systems have been poorly studied with respect to biodegradation, prompting the testing here of six major ring structural subclasses using a well-characterized bacterium and a silica encapsulation system previously shown to enhance biodegradation. The direct biological oxygenation of spiro ring compounds was demonstrated here. These and other hydrocarbon ring compounds have previously been shown to be present in flow-back waters and waters produced from hydraulic fracturing operations. Pseudomonas sp. strain NCIB 9816-4, containing naphthalene dioxygenase, was selected for its broad substrate specificity, and it was demonstrated here to oxidize fundamental ring structures that are common in shale-derived waters but not previously investigated with this or related enzymes. Pseudomonas sp. NCIB 9816-4 was tested here in the presence of a silica encasement, a protocol that has previously been shown to protect bacteria against the extremes of salinity present in fracking wastewaters. These studies demonstrate the degradation of highly hydrophobic compounds by a silica-encapsulated model bacterium, demonstrate what it may not degrade, and contribute to knowledge of the full range of hydrocarbon ring compounds that can be oxidized using Pseudomonas sp. NCIB 9816-4.

  8. Use of Silica-Encapsulated Pseudomonas sp. Strain NCIB 9816-4 in Biodegradation of Novel Hydrocarbon Ring Structures Found in Hydraulic Fracturing Waters

    Science.gov (United States)

    Aukema, Kelly G.; Kasinkas, Lisa; Aksan, Alptekin

    2014-01-01

    The most problematic hydrocarbons in hydraulic fracturing (fracking) wastewaters consist of fused, isolated, bridged, and spiro ring systems, and ring systems have been poorly studied with respect to biodegradation, prompting the testing here of six major ring structural subclasses using a well-characterized bacterium and a silica encapsulation system previously shown to enhance biodegradation. The direct biological oxygenation of spiro ring compounds was demonstrated here. These and other hydrocarbon ring compounds have previously been shown to be present in flow-back waters and waters produced from hydraulic fracturing operations. Pseudomonas sp. strain NCIB 9816-4, containing naphthalene dioxygenase, was selected for its broad substrate specificity, and it was demonstrated here to oxidize fundamental ring structures that are common in shale-derived waters but not previously investigated with this or related enzymes. Pseudomonas sp. NCIB 9816-4 was tested here in the presence of a silica encasement, a protocol that has previously been shown to protect bacteria against the extremes of salinity present in fracking wastewaters. These studies demonstrate the degradation of highly hydrophobic compounds by a silica-encapsulated model bacterium, demonstrate what it may not degrade, and contribute to knowledge of the full range of hydrocarbon ring compounds that can be oxidized using Pseudomonas sp. NCIB 9816-4. PMID:24907321

  9. Uranium and thorium sequestration by a Pseudomonas sp.: mechanism and chemical characterization.

    Science.gov (United States)

    Kazy, Sufia K; D'Souza, S F; Sar, Pinaki

    2009-04-15

    The mechanism and chemical nature of uranium and thorium sequestration by a Pseudomonas strain was investigated by transmission electron microscopy, energy dispersive X-ray (EDX) analysis, FTIR spectroscopy and X-ray diffractometry. Atomic force microscopy (AFM) used in the tapping mode elucidated the morphological changes in bacterial cells following uranium and thorium binding. Transmission electron microscopy revealed intracellular sequestration of uranium and thorium throughout the cell cytoplasm with electron dense microprecipitations of accumulated metals. Energy dispersive X-ray analysis confirmed the cellular deposition of uranium and thorium. EDX and elemental analysis of sorption solution indicated the binding of uranium and thorium by the bacterial biomass via displacement of cellular potassium and calcium. The strong involvement of cellular phosphate, carboxyl and amide groups in radionuclide binding was ascertained by FTIR spectroscopy. X-ray powder diffraction (XRD) analyses confirmed cellular sequestration of crystalline uranium and thorium phosphates. Overall results indicate that a combined ion-exchange-complexation-microprecipitation mechanism could be involved in uranium and thorium sequestration by this bacterium. Atomic force microscopy and topography analysis revealed an undamaged cell surface with an increase in cell length, width and height following radionuclide accumulation. The arithmetic average roughness (R(a)) and root mean square (RMS) roughness (R(q)) values indicated an increase in surface roughness following uranium and thorium sequestration.

  10. Polycyclic aromatic hydrocarbon degradation by biosurfactant-producing Pseudomonas sp. IR1

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, M. [Unidad de Biotecnologia del Petroleo, Centro de Biotecnologia, Fundacion Inst. de Estudios Avanzados (IDEA), Caracas (Venezuela); Synthesis and Biotics Div., Indian Oil Corp., Research and Development Center, Haryana (India); Leon, V.; Materano, A.D.S.; Ilzins, O.A.; Galindo-Castro, I.; Fuenmayor, S.L. [Unidad de Biotecnologia del Petroleo, Centro de Biotecnologia, Fundacion Inst. de Estudios Avanzados (IDEA), Caracas (Venezuela)

    2006-03-15

    We characterized a newly isolated bacterium, designated as IR1, with respect to its ability to degrade polycyclic aromatic hydrocarbons (PAHs) and to produce biosurfactants. Isolated IR1 was identified as Pseudomonas putida by analysis of 16S rRNA sequences (99.6% homology). It was capable of utilizing two-, three- and four-ring PAHs but not hexadecane and octadecane as a sole carbon and energy source. PCR and DNA hybridization studies showed that enzymes involved in PAH metabolism were related to the naphthalene dioxygenase pathway. Observation of both tensio-active and emulsifying activities indicated that biosurfactants were produced by IR1 during growth on both water miscible and immiscible substrates. The biosurfactants lowered the surface tension of medium from 54.9 dN cm{sup -1} to 35.4 dN cm{sup -1} and formed a stable and compact emulsion with an emulsifying activity of 74% with diesel oil, when grown on dextrose. These findings indicate that this isolate may be useful for bioremediation of sites contaminated with aromatic hydrocarbons. (orig.)

  11. Isolation, plant colonization potential, and phenanthrene degradation performance of the endophytic bacterium Pseudomonas sp. Ph6-gfp

    Science.gov (United States)

    Sun, Kai; Liu, Juan; Gao, Yanzheng; Jin, Li; Gu, Yujun; Wang, Wanqing

    2014-06-01

    This investigation provides a novel method of endophyte-aided removal of polycyclic aromatic hydrocarbons (PAHs) from plant bodies. A phenanthrene-degrading endophytic bacterium Pseudomonas sp. Ph6 was isolated from clover (Trifolium pratense L.) grown in a PAH-contaminated site. After being marked with the GFP gene, the colonization and distribution of strain Ph6-gfp was directly visualized in plant roots, stems, and leaves for the first time. After ryegrass (Lolium multiflorum Lam.) roots inoculation, strain Ph6-gfp actively and internally colonized plant roots and transferred vertically to the shoots. Ph6-gfp had a natural capacity to cope with phenanthrene in vitro and in planta. Ph6-gfp degraded 81.1% of phenanthrene (50 mg.L-1) in a culture solution within 15 days. The inoculation of plants with Ph6-gfp reduced the risks associated with plant phenanthrene contamination based on observations of decreased concentration, accumulation, and translocation factors of phenanthrene in ryegrass. Our results will have important ramifications in the assessment of the environmental risks of PAHs and in finding ways to circumvent plant PAH contamination.

  12. SecG is required for antibiotic activities of Pseudomonas sp. YL23 against Erwinia amylovora and Dickeya chrysanthemi.

    Science.gov (United States)

    Liu, Youzhou; Baird, Sonya M; Qiao, Junqing; Du, Yan; Lu, Shi-En

    2015-05-01

    Strain YL23 was isolated from soybean root tips and identified to be Pseudomonas sp. This strain showed broad-spectrum antibacterial activity against bacterial pathogens that are economically important in agriculture. To characterize the genes dedicated to antibacterial activities against microbial phytopathogens, a Tn5-mutation library of YL23 was constructed. Plate bioassays revealed that the mutant YL23-93 lost its antibacterial activities against Erwinia amylovora and Dickeya chrysanthemi as compared with its wild type strain. Genetic and sequencing analyses localized the transposon in a homolog of the secG gene in the mutant YL23-93. Constitutive expression plasmid pUCP26-secG was constructed and electroporated into the mutant YL23-93. Introduction of the plasmid pUCP26-secG restored antibacterial activities of the mutant YL23-93 to E. amylovora and D. chrysanthemi. As expected, empty plasmid pUCP26 could not complement the phenotype of the antibacterial activity in the mutant. Thus the secG gene, belonging to the Sec protein translocation system, is required for antibacterial activity of strain YL23 against E. amylovora and D. chrysanthemi.

  13. Enhanced phenol degradation by Pseudomonas sp. SA01: Gaining insight into the novel single and hybrid immobilizations

    Energy Technology Data Exchange (ETDEWEB)

    Mollaei, Monir [National Institute of Genetic Engineering and Biotechnology (NIGEB), P.O. Box 14155-6343, Tehran (Iran, Islamic Republic of); Abdollahpour, Saeeide [National Institute of Genetic Engineering and Biotechnology (NIGEB), P.O. Box 14155-6343, Tehran (Iran, Islamic Republic of); Department of Clinical Biochemistry, Faculty of Medicine, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Atashgahi, Siavash; Abbasi, Habib; Masoomi, Fatemeh; Rad, Iman [National Institute of Genetic Engineering and Biotechnology (NIGEB), P.O. Box 14155-6343, Tehran (Iran, Islamic Republic of); Lotfi, Abbas Sahebghadam [National Institute of Genetic Engineering and Biotechnology (NIGEB), P.O. Box 14155-6343, Tehran (Iran, Islamic Republic of); Department of Clinical Biochemistry, Faculty of Medicine, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Zahiri, Hossein Shahbani [National Institute of Genetic Engineering and Biotechnology (NIGEB), P.O. Box 14155-6343, Tehran (Iran, Islamic Republic of); Vali, Hojatollah [Department of Anatomy and Cell Biology, McGill University, Montreal (Canada); Noghabi, Kambiz Akbari, E-mail: Akbari@nigeb.ac.ir [National Institute of Genetic Engineering and Biotechnology (NIGEB), P.O. Box 14155-6343, Tehran (Iran, Islamic Republic of)

    2010-03-15

    In this work, Pseudomonas sp. SA01 cells were immobilized in a series of singular and hybrid immobilization techniques to achieve enhanced phenol removal. The singular immobilization strategies consisted of various concentrations of alginate (2-4%) and pectin (3-5%), while the hybrid strategies incorporated polyvinyl alcohol (PVA)-alginate and glycerol-alginate beads and alginate-chitosan-alginate (ACA) capsules. Immobilization protected cells against phenol and resulted in remarkable reduction (65%) in degradation time by cells immobilized in either alginate (3%) beads, in a hybrid PVA-alginate beads, or in ACA capsules compared to freely suspended cells. Cells immobilized in PVA-alginate and ACA provided the best performance in experiments using elevated phenol concentrations, up to 2000 mg/L, with complete degradation of 2000 mg/L phenol after 100 and 110 h, respectively. Electron microscopy examination indicated that cell loading capacity was increased in PVA-alginate hybrid beads through reduced cell leakage, resulting in higher activity of PVA-alginate hybrid beads compared to all other immobilization methods.

  14. Characterization of Strain Pseudomonas sp.Q1 in Microbial Fuel Cell for Treatment of Quinoline-Contaminated Water

    Institute of Scientific and Technical Information of China (English)

    ZHANG Cui-Ping; CHEN Shan-Shan; LIU Guang-Li; ZHANG Ren-Duo; XIE Jian

    2012-01-01

    To find new strain in the microbial fuel cell (MFC) for quinoline removal from wastewater and soil,a facultative anaerobic bacterium strain was isolated from the anode of MFC,utilizing quinoline as the carbon source and electron donor.Based on the 16S rRNA sequence analysis,the bacterium strain was Gram-negative and identified as Pseudomonas sp.Q1 according to its morphology and physiochemical properties.The strain was inoculated into a double-chambered MFC using various quinoline concentratious (0,50,75,86,100,150,200 and 300 mg L-1) combining with 300 mg L-1 glucose as the fuel.Results showed that electricity was generated from the MFC,in which quinoline was degraded simultaneously.The values of Coulombic efficiency (CE) increased with the increase of quinoline concentrations from 0 to 100 mg L-1 then decreased with the increase of quinoline concentration from 100 to 300 mg L-1,and the maximum CE 36.7% was obtained at the quinoline concentration of 100 mg L-1.The cyclic voltammetry analysis suggested that the mechanism of electron transfer was through excreting mediators produced by the strain Q1.The MFC should be a potential method for the treatment of quinoline-contaminated water and soil.

  15. Molecular determinants of the regioselectivity of toluene/o-xylene monooxygenase from Pseudomonas sp. strain OX1.

    Science.gov (United States)

    Notomista, Eugenio; Cafaro, Valeria; Bozza, Giuseppe; Di Donato, Alberto

    2009-02-01

    Bacterial multicomponent monooxygenases (BMMs) are a heterogeneous family of di-iron monooxygenases which share the very interesting ability to hydroxylate aliphatic and/or aromatic hydrocarbons. Each BMM possesses defined substrate specificity and regioselectivity which match the metabolic requirements of the strain from which it has been isolated. Pseudomonas sp. strain OX1, a strain able to metabolize o-, m-, and p-cresols, produces the BMM toluene/o-xylene monooxygenase (ToMO), which converts toluene to a mixture of o-, m-, and p-cresol isomers. In order to investigate the molecular determinants of ToMO regioselectivity, we prepared and characterized 15 single-mutant and 3 double-mutant forms of the ToMO active site pocket. Using the Monte Carlo approach, we prepared models of ToMO-substrate and ToMO-reaction intermediate complexes which allowed us to provide a molecular explanation for the regioselectivities of wild-type and mutant ToMO enzymes. Furthermore, using binding energy values calculated by energy analyses of the complexes and a simple mathematical model of the hydroxylation reaction, we were able to predict quantitatively the regioselectivities of the majority of the variant proteins with good accuracy. The results show not only that the fine-tuning of ToMO regioselectivity can be achieved through a careful alteration of the shape of the active site but also that the effects of the mutations on regioselectivity can be quantitatively predicted a priori.

  16. Growth of Pseudomonas sp. TX1 on a wide range of octylphenol polyethoxylate concentrations and the formation of dicarboxylated metabolites.

    Science.gov (United States)

    Lin, Yi-Wen; Guo, Gia-Luen; Hsieh, Hsiao-Cheng; Huang, Shir-Ly

    2010-04-01

    Pseudomonas sp. TX1, is able to use octylphenol polyethoxylates (OPEO(n), or Triton X-100; average n = 9.5) as a sole carbon source. It can grow on 0.05-20% of OPEO(n) with a specific growth rate of 0.34-0.44 h(-1). High-performance liquid chromatography-mass spectrometer analysis of OPEO(n) degraded metabolites revealed that strain TX1 was able to shorten the ethoxylate chain and produce octylphenol (OP). Furthermore, formation of the short carboxylate metabolites, such as carboxyoctylphenol polyethoxylates (COPEO(n), n = 2, 3) and carboxyoctylphenol polyethoxycarboxylates (COPEC(n), n = 2, 3) began at the log stage, while octylphenol polyethoxycarboxylates (OPEC(n), n = 1-3) was formed at the stationary phase. All the short-ethoxylated metabolites, OPEO(n), OPEC(n), COPEO(n), and COPEC(n), accumulated when the cells were in the stationary phase. This study is the first to demonstrate the formation of COPEO(n) and COPEC(n) from OPEO(n) by an aerobic bacterium.

  17. Proteomic analysis of sulfur-nitrogen-carbon removal by Pseudomonas sp. C27 under micro-aeration condition.

    Science.gov (United States)

    Guo, Hongliang; Chen, Chuan; Lee, Duu-Jong; Wang, Aijie; Ren, Nanqi

    2014-03-05

    Pseudomonas sp. C27 is a facultative autotrophic bacterium (FAB) that can effectively conduct mixotrophic and heterotrophic denitrifying sulfide removal (DSR) reactions under anaerobic condition using organic matters and sulfide as electron donors. Micro-aeration was proposed to enhance DSR reaction by FAB; however, there is no experimental proof on the effects of micro-aeration on capacity of denitrifying sulfide removal of FAB on proteomic levels. The proteome in total C27 cell extracts was observed by two-dimensional gel electrophoresis. Differentially expressed protein spots and specifically expressed protein spots were identified by MALDI TOF/TOF MS. We identified 55 microaerobic-responsive protein spots, representing 55 unique proteins. Hierarchical clustering analysis revealed that 75% of the proteins were up-regulated, and 5% of the proteins were specifically expressed under micro-aerobic conditions. These enzymes were mainly involved in membrane transport, protein folding and metabolism. The noted expression changes of the microaerobic-responsive proteins suggests that C27 strain has a highly efficient enzyme system to conduct DSR reactions under micro-aerobic condition. Additionally, micro-aeration can increase the rates of protein synthesis and cell growth, and enhance cell defensive system of the strain. Copyright © 2013 Elsevier Inc. All rights reserved.

  18. Effect of corn plant on survival and phenanthrene degradation capacity of Pseudomonas sp. UG14LR in two soils.

    Science.gov (United States)

    Chouychai, Waraporn; Thongkukiatkul, Amporn; Upatham, Suchart; Pokethitiyook, Prayad; Kruatrachue, Maleeya; Lee, Hung

    2012-07-01

    A study was undertaken to assess if corn (Zea mays L.) can enhance phenanthrene degradation in two soils inoculated with Pseudomonas sp. UG14Lr. Corn increased the number of UG14Lr cells in both soils, especially in the acidic soiL Phenanthrene was degraded to a greater extent in UG14Lr-inoculated or corn-planted soils than uninoculated and unplanted soils. The spiked phenanthrene was completely removed within 70 days in all the treatments in slightly alkaline soil. However, in acidic soil, complete phenanthrene removal was found only in the corn-planted treatments. The shoot and root lengths of corn grown in UG14Lr-inoculated soils were not different from those in non-inoculated soil between the treatments. The results showed that in unplanted soil, low pH adversely affected the survival and phenanthrene degradation ability of UG14Lr. Planting of corn significantly enhanced the survival of UG14Lr cells in both the bulk and rhizospheric soil, and this in turn significantly improved phenanthrene degradation in acidic soil. Re-inoculation of UG14Lr in the acidic soil increased the number of UG14Lr cells and enhanced phenanthrene degradation in unplanted soil. However, in corn-planted acidic soils, re-inoculation of UG14Lr did not further enhance the already active phenanthrene degradation occurring in both the bulk or rhizospheric soils.

  19. Anaerobic biodegradation of high-molecular-weight polycyclic aromatic hydrocarbons by a facultative anaerobe Pseudomonas sp. JP1.

    Science.gov (United States)

    Liang, Lei; Song, Xiaohui; Kong, Jing; Shen, Chenghui; Huang, Tongwang; Hu, Zhong

    2014-11-01

    Polycyclic aromatic hydrocarbons (PAHs) are harmful persistent organic pollutants, while the high-molecular-weight (HMW) PAHs are even more detrimental to the environment and human health. However, microbial anaerobic degradation of HMW PAHs has rarely been reported. One facultative anaerobe Pseudomonas sp. JP1 was isolated from Shantou Bay, Shantou, China, which could degrade a variety of HMW PAHs. After 40 days cultivation with strain JP1, anaerobic biodegradation rate of benzo[a]pyrene (BaP), fluoranthene, and phenanthrene was 30, 47, and 5 %, respectively. Consumption of nitrate as the electron acceptor was confirmed by N-(1-naphthyl) ethylenediamine spectrophotometry. Supplementation of sodium sulfite, maltose, or glycine, and in a salinity of 0-20 ‰ significantly stimulated anaerobic degradation of BaP. Lastly, the anaerobic degradation metabolites of BaP by strain JP1 were investigated using GC/MS, and the degradation pathway was proposed. This study is helpful for further studies on the mechanism of anaerobic biodegradation of PAHs.

  20. Biodegradation of malachite green by Pseudomonas sp. strain DY1 under aerobic condition: characteristics, degradation products, enzyme analysis and phytotoxicity.

    Science.gov (United States)

    Du, Lin-Na; Wang, Sheng; Li, Gang; Wang, Bing; Jia, Xiao-Ming; Zhao, Yu-Hua; Chen, Yun-Long

    2011-03-01

    Malachite green (MG), a widely-used and recalcitrant dye, has been confirmed to be carcinogenic and mutagenic against many organisms. The main objective of this study is to investigate the capability of Pseudomonas sp. strain DY1 to decolorize MG, and to explore the possible mechanism. The results showed that this strain demonstrated high decolorizing capability (90.3-97.2%) at high concentrations of MG (100-1,000 mg/l) under shaking condition within 24 h. In static conditions, lower but still effective decolorization (78.9-84.3%) was achieved. The optimal pH and temperature for the decolorization was pH 6.6 and 28-30°C, respectively. Mg(2+) and Mn(2+) (1 mM) were observed to significantly enhance the decolorization. The intermediates of the MG degradation under aerobic condition identified by UV-visible, GC-MS and LC-MS analysis included malachite green carbinol, (dimethyl amino-phenyl)-phenyl-methanone, N,N-dimethylaniline, (methyl amino-phenyl)-phenyl-methanone, (amino phenyl)-phenyl methanone and di-benzyl methane. The enzyme analysis indicated that Mn-peroxidase, NADH-DCIP and MG reductase were involved in the biodegradation of MG. Moreover, phytotoxicity of MG and detoxification for MG by the strain were observed. Therefore, this strain could be potentially used for bioremediation of MG.

  1. Effect of Transient Nicotine Load Shock on the Performance of Pseudomonas sp. HF-1 Bioaugmented Sequencing Batch Reactors

    Directory of Open Access Journals (Sweden)

    Dong-sheng Shen

    2016-01-01

    Full Text Available Bioaugmentation with degrading bacteria can improve the treatment of nicotine-containing tobacco industrial wastewater effectively. However, the transient and extremely high feeding of pollutants may compromise the effectiveness of the bioaugmented reactors. The effect of transient nicotine shock loads on the performance of Pseudomonas sp. HF-1 bioaugmented SBRs were studied. The results showed that, under 500–2500 mg/L of transient nicotine shocks, all the reactors still could realize 100% of nicotine degradation in 4 days of recovery, while the key nicotine degradation enzyme HSP hydroxylase increased in expression. Though the dramatic increase of activities of ROS, MDA, SOD, and CAT suggested that transient nicotine shock loads could induce oxidative stress on microorganisms in activated sludge, a decrease to control level demonstrated that most of the microorganisms could resist 500–1500 mg/L of transient nicotine shock under the protection from strain HF-1. After 8 cycles of recovery, high ROS level and low TOC removal in high transient shock reactors implied that 2000–2500 mg/L of transient nicotine shock was out of its recovery of strain HF-1 bioaugmented system. This study enriched our understanding on highly efficient nicotine-degrading strain bioaugmented system, which would be beneficial to tobacco waste or wastewater treatment in engineering.

  2. CAMELLIA SINENSIS LEAVES A NEW TREATMENT AGAINST URINARY TRACT INFECTION CAUSED BY PSEUDOMONAS FLUORESCENS AND SERRATIA SP

    Directory of Open Access Journals (Sweden)

    A.L. Tariq* and A.L. Reyaz

    2013-04-01

    Full Text Available ABSTRACT: Urinary tract infection is the most common disease in females and males which is big threat of kidney failure. The increasing interest is in the powerful biological activity of medicinal plant containing bioactive compounds which paves way for the importance to determine their antibacterial activity. The bioactive chemical determination revealed the presence of bioactive constituents’ steroids, alkaloids, tannins and flavonoids due the color change in the reaction tubes. While the absence of terpenoids saponins and glycosides as there was no color change in the reaction tubes. The total flavonoid content was 16mg/gram while total phenolic compound was 0.9grams in the leave extract of Camellia sinensis. The reducing power was found 0.13grams/gram of leave extracts. The phenolic extract of Camellia sinensis showed the antibacterial activity against Pseudomonas fluorescens and Serratia Sp by showing maximum zone of inhibition around the bacterial colonies when compared with standard antibiotics Cotrimaxazole, Norfloxacin, Chloramphenicol, and Nalidixic acid.

  3. Simultaneous removal of Cr(Ⅵ) and phenol in consortium culture of Bacillus sp. and Pseudomonas putida Migula (CCTCC AB92019)

    Institute of Scientific and Technical Information of China (English)

    LIU Yun-guo; PAN Cui; XIA Wen-bin; ZENG Guang-ming; ZHOU Ming; LIU Yuan-yuan; KE Jie; HUANG Chao

    2008-01-01

    The simultaneous removal of Cr(Ⅵ) and phenol in a consortium culture containing Cr(Ⅵ) reducer, Bacillus sp. and phenol degrader, Pseudomonas putida Migula (CCTCC AB92019) was studied. Phenol was used as the sole carbon source. Bacillus sp. utilized metabolites formed from phenol degradation as electron donors and energy source for Cr(Ⅵ) reduction. Optimum Cr(Ⅵ) reduction was observed at a phenol concentration of 150 mg/L and an initial Cr(Ⅵ) concentration of 15 mg/L. Both the Cr(Ⅵ) reduction and phenol degradation were influenced by the cell composition of the culture, but the phenol degradation was not significantly affected by the content of Bacillus sp. The experiments also showed that the amount of phenol degraded was more than that stoichiometrically required for Cr(Ⅵ) reduction.

  4. Transcriptional activation of multiple operons involved in para-nitrophenol degradation by Pseudomonas sp. Strain WBC-3.

    Science.gov (United States)

    Zhang, Wen-Mao; Zhang, Jun-Jie; Jiang, Xuan; Chao, Hongjun; Zhou, Ning-Yi

    2015-01-01

    Pseudomonas sp. strain WBC-3 utilizes para-nitrophenol (PNP) as a sole carbon and energy source. The genes involved in PNP degradation are organized in the following three operons: pnpA, pnpB, and pnpCDEFG. How the expression of the genes is regulated is unknown. In this study, an LysR-type transcriptional regulator (LTTR) is identified to activate the expression of the genes in response to the specific inducer PNP. While the LTTR coding gene pnpR was found to be not physically linked to any of the three catabolic operons, it was shown to be essential for the growth of strain WBC-3 on PNP. Furthermore, PnpR positively regulated its own expression, which is different from the function of classical LTTRs. A regulatory binding site (RBS) with a 17-bp imperfect palindromic sequence (GTT-N11-AAC) was identified in all pnpA, pnpB, pnpC, and pnpR promoters. Through electrophoretic mobility shift assays and mutagenic analyses, this motif was proven to be necessary for PnpR binding. This consensus motif is centered at positions approximately -55 bp relative to the four transcriptional start sites (TSSs). RBS integrity was required for both high-affinity PnpR binding and transcriptional activation of pnpA, pnpB, and pnpR. However, this integrity was essential only for high-affinity PnpR binding to the promoter of pnpCDEFG and not for its activation. Intriguingly, unlike other LTTRs studied, no changes in lengths of the PnpR binding regions of the pnpA and pnpB promoters were observed after the addition of the inducer PNP in DNase I footprinting.

  5. Does S-metolachlor affect the performance of Pseudomonas sp. strain ADP as bioaugmentation bacterium for atrazine-contaminated soils?

    Directory of Open Access Journals (Sweden)

    Cristina A Viegas

    Full Text Available Atrazine (ATZ and S-metolachlor (S-MET are two herbicides widely used, often as mixtures. The present work examined whether the presence of S-MET affects the ATZ-biodegradation activity of the bioaugmentation bacterium Pseudomonas sp. strain ADP in a crop soil. S-MET concentrations were selected for their relevance in worst-case scenarios of soil contamination by a commercial formulation containing both herbicides. At concentrations representative of application of high doses of the formulation (up to 50 µg g(-1 of soil, corresponding to a dose approximately 50× higher than the recommended field dose (RD, the presence of pure S-MET significantly affected neither bacteria survival (~10(7 initial viable cells g(-1 of soil nor its ATZ-mineralization activity. Consistently, biodegradation experiments, in larger soil microcosms spiked with 20× or 50 × RD of the double formulation and inoculated with the bacterium, revealed ATZ to be rapidly (in up to 5 days and extensively (>96% removed from the soil. During the 5 days, concentration of S-MET decreased moderately to about 60% of the initial, both in inoculated and non-inoculated microcosms. Concomitantly, an accumulation of the two metabolites S-MET ethanesulfonic acid and S-MET oxanilic acid was found. Despite the dissipation of almost all the ATZ from the treated soils, the respective eluates were still highly toxic to an aquatic microalgae species, being as toxic as those from the untreated soil. We suggest that this high toxicity may be due to the S-MET and/or its metabolites remaining in the soil.

  6. Aerobic degradation of N-methyl-4-nitroaniline (MNA by Pseudomonas sp. strain FK357 isolated from soil.

    Directory of Open Access Journals (Sweden)

    Fazlurrahman Khan

    Full Text Available N-Methyl-4-nitroaniline (MNA is used as an additive to lower the melting temperature of energetic materials in the synthesis of insensitive explosives. Although the biotransformation of MNA under anaerobic condition has been reported, its aerobic microbial degradation has not been documented yet. A soil microcosms study showed the efficient aerobic degradation of MNA by the inhabitant soil microorganisms. An aerobic bacterium, Pseudomonas sp. strain FK357, able to utilize MNA as the sole carbon, nitrogen, and energy source, was isolated from soil microcosms. HPLC and GC-MS analysis of the samples obtained from growth and resting cell studies showed the formation of 4-nitroaniline (4-NA, 4-aminophenol (4-AP, and 1, 2, 4-benzenetriol (BT as major metabolic intermediates in the MNA degradation pathway. Enzymatic assay carried out on cell-free lysates of MNA grown cells confirmed N-demethylation reaction is the first step of MNA degradation with the formation of 4-NA and formaldehyde products. Flavin-dependent transformation of 4-NA to 4-AP in cell extracts demonstrated that the second step of MNA degradation is a monooxygenation. Furthermore, conversion of 4-AP to BT by MNA grown cells indicates the involvement of oxidative deamination (release of NH2 substituent reaction in third step of MNA degradation. Subsequent degradation of BT occurs by the action of benzenetriol 1, 2-dioxygenase as reported for the degradation of 4-nitrophenol. This is the first report on aerobic degradation of MNA by a single bacterium along with elucidation of metabolic pathway.

  7. Draft Genome Sequence Analysis of a Pseudomonas putida W15Oct28 Strain with Antagonistic Activity to Gram-Positive and Pseudomonas sp. Pathogens

    NARCIS (Netherlands)

    Ye, L.; Hildebrandt, F.; Ballet, S.; Laus, M.S.; Berendsen, Roeland; Cornelis, P.

    2014-01-01

    Pseudomonas putida is a member of the fluorescent pseudomonads known to produce the yellow-green fluorescent pyoverdine siderophore. P. putida W15Oct28, isolated from a stream in Brussels, was found to produce compound(s) with antimicrobial activity against the opportunistic pathogens Staphylococcus

  8. Identification of the para-nitrophenol catabolic pathway, and characterization of three enzymes involved in the hydroquinone pathway, in pseudomonas sp. 1-7

    Directory of Open Access Journals (Sweden)

    Zhang Shuangyu

    2012-03-01

    Full Text Available Abstract Background para-Nitrophenol (PNP, a priority environmental pollutant, is hazardous to humans and animals. However, the information relating to the PNP degradation pathways and their enzymes remain limited. Results Pseudomonas sp.1-7 was isolated from methyl parathion (MP-polluted activated sludge and was shown to degrade PNP. Two different intermediates, hydroquinone (HQ and 4-nitrocatechol (4-NC were detected in the catabolism of PNP. This indicated that Pseudomonas sp.1-7 degraded PNP by two different pathways, namely the HQ pathway, and the hydroxyquinol (BT pathway (also referred to as the 4-NC pathway. A gene cluster (pdcEDGFCBA was identified in a 10.6 kb DNA fragment of a fosmid library, which cluster encoded the following enzymes involved in PNP degradation: PNP 4-monooxygenase (PdcA, p-benzoquinone (BQ reductase (PdcB, hydroxyquinol (BT 1,2-dioxygenase (PdcC, maleylacetate (MA reductase (PdcF, 4-hydroxymuconic semialdehyde (4-HS dehydrogenase (PdcG, and hydroquinone (HQ 1,2-dioxygenase (PdcDE. Four genes (pdcDEFG were expressed in E. coli and the purified pdcDE, pdcG and pdcF gene products were shown to convert HQ to 4-HS, 4-HS to MA and MA to β-ketoadipate respectively by in vitro activity assays. Conclusions The cloning, sequencing, and characterization of these genes along with the functional PNP degradation studies identified 4-NC, HQ, 4-HS, and MA as intermediates in the degradation pathway of PNP by Pseudomonas sp.1-7. This is the first conclusive report for both 4-NC and HQ- mediated degradation of PNP by one microorganism.

  9. Surface motility in Pseudomonas sp. DSS73 is required for efficient biological containment of the root-pathogenic microfungi Rhizoctonia solani and Pythium ultimum

    DEFF Research Database (Denmark)

    Andersen, Jens Bo; Koch, Birgit; Nielsen, Tommy Harder

    2003-01-01

    Pseudomonas sp. DSS73 was isolated from the rhizoplane of sugar beet seedlings. This strain exhibits antagonism towards the root-pathogenic microfungi Pythium ultimum and Rhizoctonia solani. Production of the cyclic lipopeptide amphisin in combination with expression of flagella enables the growi...... bacterial culture to move readily over the surface of laboratory media. Amphisin is a new member of a group of dual-functioning compounds such as tensin, viscosin and viscosinamid that display both biosurfactant and antifungal properties. The ability of DSS73 to efficiently contain root...

  10. Surface motility in Pseudomonas sp DSS73 is required for efficient biological containment of the root-pathogenic microfungi Rhizoctonia solani and Pythium ultimum

    DEFF Research Database (Denmark)

    Andersen, Jens Bo; Koch, Birgit; Nielsen, T.H.;

    2003-01-01

    Pseudomonas sp. DSS73 was isolated from the rhizoplane of sugar beet seedlings. This strain exhibits antagonism towards the root-pathogenic microfungi Pythium ultimum and Rhizoctonia solani. Production of the cyclic lipopeptide amphisin in combination with expression of flagella enables the growing...... bacterial culture to move readily over the surface of laboratory media. Amphisin is a new member of a group of dual-functioning compounds such as tensin, viscosin and viscosinamid that display both biosurfactant and antifungal properties. The ability of DSS73 to efficiently contain root...

  11. Pseudomonas aestusnigri sp. nov., isolated from crude oil-contaminated intertidal sand samples after the Prestige oil spill.

    Science.gov (United States)

    Sánchez, David; Mulet, Magdalena; Rodríguez, Ana C; David, Zoyla; Lalucat, Jorge; García-Valdés, Elena

    2014-03-01

    Strains VGXO14(T) and Vi1 were isolated from the Atlantic intertidal shore from Galicia, Spain, after the Prestige oil spill. Both strains were Gram-negative rod-shaped bacteria with one polar inserted flagellum, strictly aerobic, and able to grow at 18-37°C, pH 6-10 and 2-10% NaCl. A preliminary analysis of the 16S rRNA and the partial rpoD gene sequences indicated that these strains belonged to the Pseudomonas genus but were distinct from any known Pseudomonas species. A polyphasic taxonomic approach including phylogenetic, chemotaxonomic, phenotypic and genotypic data confirmed that the strains belonged to the Pseudomonas pertucinogena group. In a multilocus sequence analysis, the similarity of VGXO14(T) and Vi1 to the closest type strain of the group, Pseudomonas pachastrellae, was 90.4%, which was lower than the threshold of 97% established to discriminate species in the Pseudomonas genus. The DNA-DNA hybridisation similarity between strains VGXO14(T) and Vi1 was 79.6%, but below 70% with the type strains in the P. pertucinogena group. Therefore, the strains should be classified within the genus Pseudomonas as a novel species, for which the name Pseudomonas aestusnigri is proposed. The type strain is VGXO14(T) (=CCUG 64165(T)=CECT 8317(T)).

  12. Isolation of Strain Pseudomonas sp.DY12 with Degrading Petroleum Activity and Studies on Its Degrading Performance%石油降解菌株Pseudomonas sp.DY12的筛选及降解性能研究

    Institute of Scientific and Technical Information of China (English)

    王战勇; 顾贵洲; 苏婷婷; 唐志强

    2009-01-01

    从石油炼厂污染土壤中筛选出具有石油降解能力的菌株Pseudomonas sp.DY12,并对其降解石油烃能力进行了研究.考察了培养温度、接种量、培养基初始pH值、培养时间及摇床转速对菌株降解性能的影响,优选出菌株Pseudomonas sp.DY12降解石油烃的最佳条件,即:培养时间4 d、菌悬液接种量4%(体积分数)、培养温度30℃、培养基初始pH值7.0~8.0、摇床转速160 r·min-1,在此条件下菌株Pseudomonas sp.DY12对石油烃的降解率可达69.4%.

  13. Draft genome sequence analysis of a Pseudomonas putida W15Oct28 strain with antagonistic activity to Gram-positive and Pseudomonas sp. pathogens.

    Science.gov (United States)

    Ye, Lumeng; Hildebrand, Falk; Dingemans, Jozef; Ballet, Steven; Laus, George; Matthijs, Sandra; Berendsen, Roeland; Cornelis, Pierre

    2014-01-01

    Pseudomonas putida is a member of the fluorescent pseudomonads known to produce the yellow-green fluorescent pyoverdine siderophore. P. putida W15Oct28, isolated from a stream in Brussels, was found to produce compound(s) with antimicrobial activity against the opportunistic pathogens Staphylococcus aureus, Pseudomonas aeruginosa, and the plant pathogen Pseudomonas syringae, an unusual characteristic for P. putida. The active compound production only occurred in media with low iron content and without organic nitrogen sources. Transposon mutants which lost their antimicrobial activity had the majority of insertions in genes involved in the biosynthesis of pyoverdine, although purified pyoverdine was not responsible for the antagonism. Separation of compounds present in culture supernatants revealed the presence of two fractions containing highly hydrophobic molecules active against P. aeruginosa. Analysis of the draft genome confirmed the presence of putisolvin biosynthesis genes and the corresponding lipopeptides were found to contribute to the antimicrobial activity. One cluster of ten genes was detected, comprising a NAD-dependent epimerase, an acetylornithine aminotransferase, an acyl CoA dehydrogenase, a short chain dehydrogenase, a fatty acid desaturase and three genes for a RND efflux pump. P. putida W15Oct28 genome also contains 56 genes encoding TonB-dependent receptors, conferring a high capacity to utilize pyoverdines from other pseudomonads. One unique feature of W15Oct28 is also the presence of different secretion systems including a full set of genes for type IV secretion, and several genes for type VI secretion and their VgrG effectors.

  14. Draft genome sequence analysis of a Pseudomonas putida W15Oct28 strain with antagonistic activity to Gram-positive and Pseudomonas sp. pathogens.

    Directory of Open Access Journals (Sweden)

    Lumeng Ye

    Full Text Available Pseudomonas putida is a member of the fluorescent pseudomonads known to produce the yellow-green fluorescent pyoverdine siderophore. P. putida W15Oct28, isolated from a stream in Brussels, was found to produce compound(s with antimicrobial activity against the opportunistic pathogens Staphylococcus aureus, Pseudomonas aeruginosa, and the plant pathogen Pseudomonas syringae, an unusual characteristic for P. putida. The active compound production only occurred in media with low iron content and without organic nitrogen sources. Transposon mutants which lost their antimicrobial activity had the majority of insertions in genes involved in the biosynthesis of pyoverdine, although purified pyoverdine was not responsible for the antagonism. Separation of compounds present in culture supernatants revealed the presence of two fractions containing highly hydrophobic molecules active against P. aeruginosa. Analysis of the draft genome confirmed the presence of putisolvin biosynthesis genes and the corresponding lipopeptides were found to contribute to the antimicrobial activity. One cluster of ten genes was detected, comprising a NAD-dependent epimerase, an acetylornithine aminotransferase, an acyl CoA dehydrogenase, a short chain dehydrogenase, a fatty acid desaturase and three genes for a RND efflux pump. P. putida W15Oct28 genome also contains 56 genes encoding TonB-dependent receptors, conferring a high capacity to utilize pyoverdines from other pseudomonads. One unique feature of W15Oct28 is also the presence of different secretion systems including a full set of genes for type IV secretion, and several genes for type VI secretion and their VgrG effectors.

  15. Heterologous Expression of PA8FAD9 and Functional Characterization of a Δ9-Fatty Acid Desaturase from a Cold-Tolerant Pseudomonas sp. A8.

    Science.gov (United States)

    Garba, Lawal; Ali, Mohd Shukuri Mohamad; Oslan, Siti Nurbaya; Rahman, Raja Noor Zaliha Raja Abdul

    2016-11-01

    Fatty acid desaturase enzymes are capable of inserting double bonds between carbon atoms of saturated fatty acyl-chains to produce unsaturated fatty acids. A gene coding for a putative Δ9-fatty acid desaturase-like protein was isolated from a cold-tolerant Pseudomonas sp. A8, cloned and heterologously expressed in Escherichia coli. The gene named as PA8FAD9 has an open reading frame of 1185 bp and codes for 394 amino acids with a predicted molecular weight of 45 kDa. The enzyme showed high Δ9-fatty acid desaturase-like protein activity and increased overall levels of cellular unsaturated fatty acids in the recombinant E. coli cells upon expression at different temperatures. The results showed that the ratio of palmitoleic to palmitic acid in the recombinant E. coli cells increased by more than twice the amount observed in the control cells at 20 °C using 0.4 mM IPTG. GCMS analysis confirmed the ability of this enzyme to convert exogenous stearic acid to oleic acid incorporated into the recombinant E. coli membrane phospholipids. It may be concluded that the PA8FAD9 gene from Pseudomonas sp. A8 codes for a putative Δ9-fatty acid desaturase protein actively expressed in E. coli under the influence of temperature and an inducer.

  16. Structural Adaptation of Cold-Active RTX Lipase from Pseudomonas sp. Strain AMS8 Revealed via Homology and Molecular Dynamics Simulation Approaches

    Directory of Open Access Journals (Sweden)

    Mohd. Shukuri Mohamad Ali

    2013-01-01

    Full Text Available The psychrophilic enzyme is an interesting subject to study due to its special ability to adapt to extreme temperatures, unlike typical enzymes. Utilizing computer-aided software, the predicted structure and function of the enzyme lipase AMS8 (LipAMS8 (isolated from the psychrophilic Pseudomonas sp., obtained from the Antarctic soil are studied. The enzyme shows significant sequence similarities with lipases from Pseudomonas sp. MIS38 and Serratia marcescens. These similarities aid in the prediction of the 3D molecular structure of the enzyme. In this study, 12 ns MD simulation is performed at different temperatures for structural flexibility and stability analysis. The results show that the enzyme is most stable at 0°C and 5°C. In terms of stability and flexibility, the catalytic domain (N-terminus maintained its stability more than the noncatalytic domain (C-terminus, but the non-catalytic domain showed higher flexibility than the catalytic domain. The analysis of the structure and function of LipAMS8 provides new insights into the structural adaptation of this protein at low temperatures. The information obtained could be a useful tool for low temperature industrial applications and molecular engineering purposes, in the near future.

  17. Structural adaptation of cold-active RTX lipase from Pseudomonas sp. strain AMS8 revealed via homology and molecular dynamics simulation approaches.

    Science.gov (United States)

    Mohamad Ali, Mohd Shukuri; Mohd Fuzi, Siti Farhanie; Ganasen, Menega; Abdul Rahman, Raja Noor Zaliha Raja; Basri, Mahiran; Salleh, Abu Bakar

    2013-01-01

    The psychrophilic enzyme is an interesting subject to study due to its special ability to adapt to extreme temperatures, unlike typical enzymes. Utilizing computer-aided software, the predicted structure and function of the enzyme lipase AMS8 (LipAMS8) (isolated from the psychrophilic Pseudomonas sp., obtained from the Antarctic soil) are studied. The enzyme shows significant sequence similarities with lipases from Pseudomonas sp. MIS38 and Serratia marcescens. These similarities aid in the prediction of the 3D molecular structure of the enzyme. In this study, 12 ns MD simulation is performed at different temperatures for structural flexibility and stability analysis. The results show that the enzyme is most stable at 0°C and 5°C. In terms of stability and flexibility, the catalytic domain (N-terminus) maintained its stability more than the noncatalytic domain (C-terminus), but the non-catalytic domain showed higher flexibility than the catalytic domain. The analysis of the structure and function of LipAMS8 provides new insights into the structural adaptation of this protein at low temperatures. The information obtained could be a useful tool for low temperature industrial applications and molecular engineering purposes, in the near future.

  18. Biodegradation of malachite green by strain Pseudomonas sp. K9 and cloning of the tmr2 gene associated with an ISPpu12.

    Science.gov (United States)

    Huan-Mei; Lian-Tai, Li; Cai-Fang, Yan; Jin-Jin, Sun; Yuan-Gao; Hong, Qing; Shun-Peng, Li

    2011-06-01

    A bacterial strain K9 capable of degrading malachite green was isolated from the sludge of the wastewater treatment system of a chemical plant. It was identified preliminarily as Pseudomonas sp. Strain K9 was also able to degrade other triphenylmethane dyes, such as Crystal Violet and Basic Fuchsin. The gene tmr2, encoding the triphenylmethane reductase, was cloned from strain K9, and functionally expressed in E. coli. A 5946-bp DNA fragment including the tmr2 gene was cloned from the genomic DNA of strain K9 by chromosome walking. Its sequence analysis showed that tmr2 was associated with a typical mobile element ISPpu12 consisting of tnpA (encoding a transposase), lspA (encoding a lipoprotein signal peptidase) and orf1 (encoding a putative MerR family regulator), orf2 (encoding a CDF family heavy metal/H(+) antiporter). This association was also found in another malachite green-degrading strain Pseudomonas sp. MDB-1, which indicated that the tmr2 gene might be a horizontally transferable gene.

  19. Biodegradable and biocompatible epoxidized vegetable oil modified thermostable poly(vinyl chloride): thermal and performance characteristics post biodegradation with Pseudomonas aeruginosa and Achromobacter sp.

    Science.gov (United States)

    Das, Gautam; Bordoloi, Naba K; Rai, Sudhir K; Mukherjee, Ashis K; Karak, Niranjan

    2012-03-30

    The increased production of municipal solid waste by the disposal of plastic materials heightens the urgency to develop biodegradable materials for daily use. In vitro-biodegradation study on poly(vinyl chloride) (PVC) plasticized by epoxidized Mesua ferrea L. seed oil at three different weight percentages (PVC/ENO ratio of 75/25, 50/50 and 25/75) was conducted by using Pseudomonas aeruginosa and Achromobacter sp. bacteria. The test bacterial species were able to grow on the polymer matrix by using it as a source of energy; however the pristine PVC did not support the microbial growth. The PVC/ENO material of 25/75 ratio showed the highest percent (%) of biodegradation compared to other tested systems. The bacterial count and the dry biomass post 180 days of inoculation in 25/75 plasticized PVC suggested bacterial growth at the expense of degradation of the system. The tensile strength of 25/75 PVC/ENO system, post 180 days of inoculation by Pseudomonas aeruginosa and Achromobacter sp. decreased by about 53% and 43% respectively. Further, surface erosion phenomenon and structural change of the matrix after bacterial growth, as studied by FTIR and SEM analysis of PVC/ENO of 25/75 ratio exhibited noticeable deterioration post 180 days of inoculation.

  20. Biodecolorization of Reactive Black-5 by a metal and salt tolerant bacterial strain Pseudomonas sp. RA20 isolated from Paharang drain effluents in Pakistan.

    Science.gov (United States)

    Hussain, Sabir; Maqbool, Zahid; Ali, Shafaqat; Yasmeen, Tahira; Imran, Muhammad; Mahmood, Faisal; Abbas, Farhat

    2013-12-01

    Discharge of untreated azo dyes contaminated textile wastewater into soil and water bodies causes severe contamination. The present study was conducted to isolate dye degrading bacterial strains from a textile industry wastewater carrying drain in the neighborhood of Faisalabad, Pakistan. Seventy six bacterial strains were initially isolated and was screened using liquid mineral salts medium spiked with Reactive Black-5 azo dye. The strain RA20 was found to be the most efficient azo dye degrading bacterial isolate and was identified by amplifying and sequencing its 16S rRNA. Analysis indicated that this strain belonged to genus Pseudomonas and was designated as Pseudomonas sp. RA20. It had the highest decolorization activity at pH 8 and 25 °C incubation temperature under static conditions using yeast extract as an additional C source. This strain was also effective in decolorizing structurally related other reactive dyes including Reactive Orange 16, Reactive Yellow 2 and Reactive Red 120 but with varying efficacy. RA20 decolorized Reactive Black-5 significantly in the presence of up to 30 g L⁻¹ NaCl; however, the decolorization rate was significantly (p≤0.05) reduced beyond this salt concentration. Moreover, this bacterial strain also exhibited moderate tolerance to different heavy metals including zinc (Zn), cadmium (Cd), chromium (Cr), lead (Pb) and copper (Cu). RA20 also decolorized Reactive Black-5 in the presence of a mixture of the selected heavy metals depending upon their concentrations. This study highlights the importance of Pseudomonas sp. RA20 as a prospective biological resource for bioremediation of water and soils contaminated with azo dyes.

  1. Molecular and biochemical characteristics of β-propeller phytase from marine Pseudomonas sp. BS10-3 and its potential application for animal feed additives.

    Science.gov (United States)

    Nam, Seung-Jeung; Kim, Young-Ok; Ko, Tae-Kyung; Kang, Jin-Ku; Chun, Kwang-Hoon; Auh, Joong-Hyuck; Lee, Chul-Soon; Lee, In-Kyu; Park, Sunghoon; Oh, Byung-Chul

    2014-10-01

    Phytate is an antinutritional factor that impacts the bioavailability of essential minerals such as Ca(2+), Mg(2+), Mn(2+), Zn(2+), and Fe(2+) by forming insoluble mineral-phytate salts. These insoluble mineral-phytate salts are hydrolyzed rarely by monogastric animals, because they lack the hydrolyzing phytases and thus excrete the majority of them. The β-propeller phytases (BPPs) hydrolyze these insoluble mineral-phytate salts efficiently. In this study, we cloned a novel BPP gene from a marine Pseudomonas sp. This Pseudomonas BPP gene (PsBPP) had low sequence identity with other known phytases and contained an extra internal repeat domain (residues 24-279) and a typical BPP domain (residues 280-634) at the C-terminus. Structurebased sequence alignment suggested that the N-terminal repeat domain did not possess the active-site residues, whereas the C-terminal BPP domain contained multiple calcium-binding sites, which provide a favorable electrostatic environment for substrate binding and catalytic activity. Thus, we overexpressed the BPP domain from Pseudomonas sp. to potentially hydrolyze insoluble mineral-phytate salts. Purified recombinant PsBPP required Ca(2+) or Fe(2+) for phytase activity, indicating that PsBPP hydrolyzes insoluble Fe(2+)-phytate or Ca2+-phytate salts. The optimal temperature and pH for the hydrolysis of Ca(2+)-phytate by PsBPP were 50°C and 6.0, respectively. Biochemical and kinetic studies clearly showed that PsBPP efficiently hydrolyzed Ca(2+)-phytate salts and yielded myo-inositol 2,4,6-trisphosphate and three phosphate groups as final products. Finally, we showed that PsBPP was highly effective for hydrolyzing rice bran with high phytate content. Taken together, our results suggest that PsBPP has great potential in the animal feed industry for reducing phytates.

  2. Soil bacterium Pseudomonas sp.593 synthesizes phosphatidylcholine via phosphatidylcholine synthase pathway%土壤假单胞菌593使用Pcs途径合成磷酯酰胆碱

    Institute of Scientific and Technical Information of China (English)

    熊敏; 吴彬; 何火光; 李洋; 王行国

    2011-01-01

    [Objective]Prokaryotes synthesize phosphotidylcholine by using phospholipid N-methylation or phosphatidylcholine synthase pathway or both.To confirm which pathway the soil bacterium Pseudomonas sp.593 utilizes, we tested its phosphotidylcholine synthesis, cloned the pcs gene encoding phosphatidylcholine synthase, examined Pcs activity, and constructed a pcs- mutant.[Methods]To clone the pcs gene from Pseudomonas sp.593 genomic DNA, we firstly aligned amino acid sequences of phosphatidylcholine synthases in different pseudomonas strains reported in databases.Then we designed degenerate primers based on two amino acid segments conserved in sequences of phosphatidylcholine synthases.A partial fragment of the pcs gene was finally amplified from Pseudomonas sp.593 genomic DNA.The amplified partial fragment was labeled with digoxigenin-dUTP ( DIG) as a probe, sub-cloning library of Pseudomonas sp.593 genomic DNA was prepared and then screened using DIG-labelled probe via in situ colony hybridization.DNA homologous recombination in vivo was preformed to delete pcs gene of Pseudomonas sp.593.Thinlayer chromatography ( TLC) assay was used to analyze total phospholipids, detect phosphotidylcholine content and determine pcs gene activity.[Results]TLC analysis revealed that Pseudomonas sp.593 growing in the M9 or LB medium with choline was able to synthesize phosphotidylcholine, but wasn't without addition of choline.A 894 bp DNA fragment coded a protein with phosphatidylcholine synthase activity was cloned from Pseudomonas sp.593.The pcs- mutant obtained from in vivo mutagenesis was unable to form phosphotidylcholine, no matter choline was presented in the medium or not.[Conclusion]Phosphatidylcholine synthase pathway is a sole way for phosphotidylcholine synthesis in soil bacterium Pseudomonas sp.593 or other Pseudomonas strains.%[目的]原核生物有两条代谢途径N-甲基化途径(Pmt途径)和磷脂酰胆碱合酶途径(Pcs途径)合成磷脂酰胆碱(Pc).本文对土壤细菌Pseudomonas

  3. Induced systemic resistance in cucumber and Arabidopsis thaliana by the combination of Trichoderma harzianum Tr6 and Pseudomonas sp.

    NARCIS (Netherlands)

    Alizadeh, H.; Behboudi, K.; Amadzadeh, M.; Javan-Nikkhah, M.; Zamioudis, C; Pieterse, C.M.J.; Bakker, P.A.H.M.

    2013-01-01

    Trichoderma species and fluorescent Pseudomonas spp. have been reported to induce systemic resistance in plants. In this study the effectiveness of a combination of these biological control agents on the efficacy of induced resistance was investigated in cucumber and the model plant Arabidopsis thal

  4. Biogenic Strain of Silver and Selenium Nanoparticles by Pseudomonas fluorescens and Cladosporium sp. JAPSK3 Isolated from Coal Mine Samples and Their Antimicrobial Activity

    Science.gov (United States)

    Singh, Nidhi; Saha, Prasenjit; Rajkumar, Karthik; Abraham, Jayanthi

    2014-08-01

    Selenium and silver have unique properties and great potential in the field of physics, chemistry and biology. The bacterial strain Pseudomonas fluorescens was isolated by using Kings'B media and Cladosporium sp. was isolated by using potato dextrose agar for soil sample collected from Andhra Pradesh coal field of Singareni. Rapid formation of stable silver and selenium nanoparticles (AgNPs; SeNPs) were observed on exposure of the microbial culture with solution of silver nitrate and sodium selenite. The nanoparticles were characterized by UV-visible spectroscopy, X-ray diffraction (XRD) and atomic force microscopy (AFM). Further, the biologically synthesized nanoparticles were found to have efficient antimicrobial activity against pathogenic bacteria, thus implying significance of the present study in production of biomedical products. AgNPs synthesized by P. fluorescens showed more antimicrobial activity than Cladosporium sp. As the AgNPs are much smaller in size, they showed effective antimicrobial activity when compared to that of SeNPs which showed less effective antimicrobial activity in both P. fluorescens and Cladosporium sp. The microbes are capable of reducing both AgNPs and SeNPs. The biological synthesis of nanoparticles is useful when compared with other physical and chemical methods as they are eco-friendly.

  5. 假单胞菌发酵制备精氨酸脱亚胺酶%Preparation of Arginine Deiminase by Pseudomonas sp.

    Institute of Scientific and Technical Information of China (English)

    孟繁君; 刘咏梅; 孙志浩; 倪晔; 郑璞

    2008-01-01

    采用假单胞菌(Pseudomonas sp.)发酵制备精氨酸脱亚胺酶,优化发酵培养基配方及培养条件,以葡萄糖为碳源,酵母膏和蛋白胨为氮源,30"C振荡培养20h时,发酵液中精氨酸脱亚胺酶的酶活力可达2.17u/ml.向HepG2肝癌细胞培养液中加入酶粗品0.5u/ml,对肿瘤细胞的生长抑制率为93.4%.

  6. Biodegradation of Reactive blue 13 in a two-stage anaerobic/aerobic fluidized beds system with a Pseudomonas sp. isolate.

    Science.gov (United States)

    Lin, Jun; Zhang, Xingwang; Li, Zhongjian; Lei, Lecheng

    2010-01-01

    Pseudomonas sp. strain L1 capable of degrading the azo textile dye Reactive blue 13, was isolated from activated sludge in a sequencing batch reactor. A continuous two-stage anaerobic/aerobic biological fluidized bed system was used to decolorize and mineralize Reactive blue 13. The key factors affecting decolorization were investigated and the efficiency of degradation was also optimized. An overall color removal of 83.2% and COD removal of 90.7% was achieved at pH 7, a residence time of 70 h and a glucose concentration of 2 g/L, HRT=70 h and C(glucose)=2000 mg/L. Oxygen was contributing to blocking the azo bond cleavage. Consequently, decolorization occurred in the anaerobic reactor while partial mineralization was achieved in the aerobic reactor. A possible degradation pathway based on the analysis of intermediates and involving azoreduction, desulfonation, deamination and further oxidation reactions is presented.

  7. Mercury (II) removal by resistant bacterial isolates and mercuric (II) reductase activity in a new strain of Pseudomonas sp. B50A.

    Science.gov (United States)

    Giovanella, Patricia; Cabral, Lucélia; Bento, Fátima Menezes; Gianello, Clesio; Camargo, Flávio Anastácio Oliveira

    2016-01-25

    This study aimed to isolate mercury resistant bacteria, determine the minimum inhibitory concentration for Hg, estimate mercury removal by selected isolates, explore the mer genes, and detect and characterize the activity of the enzyme mercuric (II) reductase produced by a new strain of Pseudomonas sp. B50A. The Hg removal capacity of the isolates was determined by incubating the isolates in Luria Bertani broth and the remaining mercury quantified by atomic absorption spectrophotometry. A PCR reaction was carried out to detect the merA gene and the mercury (II) reductase activity was determined in a spectrophotometer at 340 nm. Eight Gram-negative bacterial isolates were resistant to high mercury concentrations and capable of removing mercury, and of these, five were positive for the gene merA. The isolate Pseudomonas sp. B50A removed 86% of the mercury present in the culture medium and was chosen for further analysis of its enzyme activity. Mercuric (II) reductase activity was detected in the crude extract of this strain. This enzyme showed optimal activity at pH 8 and at temperatures between 37 °C and 45 °C. The ions NH4(+), Ba(2+), Sn(2+), Ni(2+) and Cd(2+) neither inhibited nor stimulated the enzyme activity but it decreased in the presence of the ions Ca(2+), Cu(+) and K(+). The isolate and the enzyme detected were effective in reducing Hg(II) to Hg(0), showing the potential to develop bioremediation technologies and processes to clean-up the environment and waste contaminated with mercury.

  8. Bioaugmentation of polyethylene succinate-contaminated soil with Pseudomonas sp. AKS2 results in increased microbial activity and better polymer degradation.

    Science.gov (United States)

    Tribedi, Prosun; Sil, Alok K

    2013-03-01

    Pseudomonas sp. AKS2 isolated from soil degrades polyethylene succinate (PES) efficiently in the laboratory. However, this organism may not be able to degrade PES with similar efficiency in a natural habitat. Since in situ remediation is preferred for the effective removal of recalcitrant materials like plastic, in the current study, bioaugmentation potential of this organism was investigated. To investigate the potential of the AKS2 strain to bioaugment the PES-contaminated soil, a microcosm-based study was carried out wherein naturally attenuated, biostimulated, and AKS2-inoculated (bioaugmented) soil samples were examined for their ability to degrade PES. The results showed better degradation of PES by bioaugmented soil than other microcosms. Consistent with it, a higher number of PES-degrading organisms were found in the bioaugmented microcosm. The bioaugmented microcosm also exhibited a higher level of average well color development in BiOLOG ECO plate assay than the other two. The corresponding Shannon-Weaver index and Gini coefficient revealed a higher soil microbial diversity of bioaugmented microcosm than the others. This was further supported by community-level physiological profile of three different microcosms wherein we have observed better utilization of different carbon sources by bioaugmented microcosms. Collectively, these results demonstrate that bioaugmentation of PES-contaminated soil with AKS2 not only enhances polymer degradation but also increases microbial diversity. Bioaugmentation of soil with AKS2 enhances PES degradation without causing damage to soil ecology. Thus, Pseudomonas sp. AKS2 has the potential to be implemented as a useful tool for in situ bioremediation of PES.

  9. Gluconic acid-producing Pseudomonas sp. prevent γ-actinorhodin biosynthesis by Streptomyces coelicolor A3(2).

    Science.gov (United States)

    Galet, Justine; Deveau, Aurélie; Hôtel, Laurence; Leblond, Pierre; Frey-Klett, Pascale; Aigle, Bertrand

    2014-09-01

    Streptomyces are ubiquitous soil bacteria well known for their ability to produce a wide range of secondary metabolites including antibiotics. In their natural environments, they co-exist and interact with complex microbial communities and their natural products are assumed to play a major role in mediating these interactions. Reciprocally, their secondary metabolism can be influenced by the surrounding microbial communities. Little is known about these complex interactions and the underlying molecular mechanisms. During pairwise co-culture experiments, a fluorescent Pseudomonas, Pseudomonas fluorescens BBc6R8, was shown to prevent the production of the diffusible blue pigment antibiotic γ-actinorhodin by Streptomyces coelicolor A3(2) M145 without altering the biosynthesis of the intracellular actinorhodin. A mutant of the BBc6R8 strain defective in the production of gluconic acid from glucose and consequently unable to acidify the culture medium did not show any effect on the γ-actinorhodin biosynthesis in contrast to the wild-type strain and the mutant complemented with the wild-type allele. In addition, when glucose was substituted by mannitol in the culture medium, P. fluorescens BBc6R8 was unable to acidify the medium and to prevent the biosynthesis of the antibiotic. All together, the results show that P. fluorescens BBc6R8 impairs the biosynthesis of the lactone form of actinorhodin in S. coelicolor by acidifying the medium through the production of gluconic acid. Other fluorescent Pseudomonas and the opportunistic pathogen Pseudomonas aeruginosa PAO1 also prevented the γ-actinorhodin production in a similar way. We propose some hypotheses on the ecological significance of such interaction.

  10. When genome-based approach meets the ‘old but good’: revealing genes involved in the antibacterial activity of Pseudomonas sp. P482 against soft rot pathogens.

    Directory of Open Access Journals (Sweden)

    Dorota Magdalena Krzyżanowska

    2016-05-01

    Full Text Available Dickeya solani and Pectobacterium carotovorum subsp. brasili¬ense are recently established species of bacterial plant pathogens causing black leg and soft rot of many vegetables and ornamental plants. Pseudomonas sp. strain P482 inhibits the growth of these pathogens, a desired trait considering the limited measures to combat these diseases. In this study, we determined the genetic background of the antibacterial activity of P482, and established the phylogenetic position of this strain.Pseudomonas sp. P482 was classified as Pseudomonas donghuensis. Genome mining revealed that the P482 genome does not contain genes determining the synthesis of known antimicrobials. However, the ClusterFinder algorithm, designed to detect atypical or novel classes of secondary metabolite gene clusters, predicted 18 such clusters in the genome. Screening of a Tn5 mutant library yielded an antimicrobial negative transposon mutant. The transposon insertion was located in a gene encoding an HpcH/HpaI aldolase/citrate lyase family protein. This gene is located in a hypothetical cluster predicted by the ClusterFinder, together with the downstream homologues of four nfs genes, that confer production of a nonfluorescent siderophore by P. donghuensis HYST. Site-directed inactivation of the HpcH/HpaI aldolase gene, the adjacent short chain dehydrogenase gene, as well as a homologue of an essential nfs cluster gene, all abolished the antimicrobial activity of the P482, suggesting their involvement in a common biosynthesis pathway. However, none of the mutants showed a decreased siderophore yield, neither was the antimicrobial activity of the wild type P482 compromised by high iron bioavailability.A genomic region comprising the nfs cluster and three upstream genes is involved in the antibacterial activity of P. donghuensis P482 against D. solani and P. carotovorum subsp. brasiliense. The genes studied are unique to the two known P. donghuensis strains. This study

  11. Application of Glomus sp. and Pseudomonas diminuta Reduce the Use of Chemical Fertilizers in Production of Potato Grown on Different Soil Types

    Science.gov (United States)

    Nurbaity, A.; Sofyan, E. T.; Hamdani, J. S.

    2016-08-01

    The use of high chemical fertilizer rates in potato production has been applied on the farm in Indonesia. Application of biofertilizer consists of arbuscular mycorrhizal fungi has been tested to reduce the use of NPK rates in production of potato and to determine whether different soil types will have different response to this biofertilizer. A greenhouse experiment was conducted using mixtures of spores of Glomus sp. and inoculant of mycorrhizal helper bacteria Pseudomonas diminuta, applied at different rates of NPK fertilizer (0, 25, 50, 75 and 100% of recommended rates) and different soil types (Andisols and Inceptisols). Results of experiment showed that application of Glomus sp. and P. diminuta reduced the use of NPK up to 50%, where the growth (plant height and tuber number), N,P,K uptake and tuber yields of potato had similar effect to the highest recommendation rate of NPK fertilizer. Inceptisols in general had better response to the biofertiliser compared to Andisols. Findings from this experiment confirmed the evidences that biofertilizer could reduce the use of chemical fertilizer, and the widely distributed soil in Indonesia such as Inceptisols, is potential to be used as a medium for potato production.

  12. Enhanced reduction of waste activated sludge at a low temperature by locally isolated strains Pseudomonas sp. VNT and Aeromonas sp. VNT.

    Science.gov (United States)

    Mohd Yasin, Nazlina Haiza; Sanchez-Torres, Viviana; Maeda, Toshinari

    2014-12-01

    Appropriate control of waste activated sludge (WAS) is required to solve the annual increment of WAS volume. The low bacterial activity at low temperatures poses a difficulty in reducing or utilizing WAS in cold weather regions and/or during the winter season. This study reveals a practical method to enhance sludge reduction at a low temperature using isolated strains of Pseudomonas and Aeromonas species. The effect of inoculating each strain into WAS was examined at different temperatures (4°C, 10°C, 12°C, 15°C, 20°C, and 30°C) and under an aerobic condition. Sludge reduction showed 2- to 8-fold improvement at the temperature range from 4°C to 15°C. Both strains are psychrophilic and can produce protease and lipase for sludge degradation even at low temperatures. Thus, biological WAS treatment at a psychrophilic temperature can be enhanced by inoculating these promising strains.

  13. Ocorrência e perfil de sensibilidade a antimicrobianos em Pseudomonas aeruginosa e Acinetobacter sp. em um hospital terciário, no sul do Brasil

    Directory of Open Access Journals (Sweden)

    Gabriele Mariani Machado

    2011-04-01

    Full Text Available INTRODUÇÃO: O principal mecanismo de resistência entre isolados de Pseudomonas aeruginosa e Acinetobacter sp. é a produção de metalo-β-lactamases (MβLs. As MβLs são enzimas capazes de hidrolisar cefalosporinas, penicilinas e carbapenêmicos, mas não monobactâmicos (aztreonam antibióticos que se encontram entre as principais opções terapêuticas para o tratamento de infecções causadas por bactérias não fermentadoras de glicose. MÉTODOS: Um estudo observacional, transversal, descritivo e retrospectivo foi desenvolvido para avaliar a frequência e o perfil de susceptibilidade cepas de P. aeruginosa e Acinetobacter sp. produtoras de MβLs isoladas no Hospital São Vicente de Paulo, Passo Fundo, Brasil. RESULTADOS: A produção de MβLs foi observada em 77,6% (n = 173/223 dos isolados de P. aeruginosa e em 22,4% (n = 50/223 dos isolados de Acinetobacter sp. Dentre as cepas produtoras de MβL, a maioria apresentou mais de 90% de resistência a seis antimicrobianos dos 12 testados, enfatizando a resistência a ceftazidima, gentamicina, aztreonam, piperaciclina/tazobactam, cefepime, ciprofloxacina, meropenem e tobramicina. CONCLUSÕES: Os índices de MβL encontrados confirmam a preocupação mundial com a disseminação desse mecanismo de resistência.

  14. Sequence analysis and structure prediction of type II Pseudomonas sp. USM 4–55 PHA synthase and an insight into its catalytic mechanism

    Directory of Open Access Journals (Sweden)

    Ahmad Khairudin Nurul

    2006-11-01

    Full Text Available Abstract Background Polyhydroxyalkanoates (PHA, are biodegradable polyesters derived from many microorganisms such as the pseudomonads. These polyesters are in great demand especially in the packaging industries, the medical line as well as the paint industries. The enzyme responsible in catalyzing the formation of PHA is PHA synthase. Due to the limited structural information, its functional properties including catalysis are lacking. Therefore, this study seeks to investigate the structural properties as well as its catalytic mechanism by predicting the three-dimensional (3D model of the Type II Pseudomonas sp. USM 4–55 PHA synthase 1 (PhaC1P.sp USM 4–55. Results Sequence analysis demonstrated that PhaC1P.sp USM 4–55 lacked similarity with all known structures in databases. PSI-BLAST and HMM Superfamily analyses demonstrated that this enzyme belongs to the alpha/beta hydrolase fold family. Threading approach revealed that the most suitable template to use was the human gastric lipase (PDB ID: 1HLG. The superimposition of the predicted PhaC1P.sp USM 4–55 model with 1HLG covering 86.2% of the backbone atoms showed an RMSD of 1.15 Å. The catalytic residues comprising of Cys296, Asp451 and His479 were found to be conserved and located adjacent to each other. In addition to this, an extension to the catalytic mechanism was also proposed whereby two tetrahedral intermediates were believed to form during the PHA biosynthesis. These transition state intermediates were further postulated to be stabilized by the formation of oxyanion holes. Based on the sequence analysis and the deduced model, Ser297 was postulated to contribute to the formation of the oxyanion hole. Conclusion The 3D model of the core region of PhaC1P.sp USM 4–55 from residue 267 to residue 484 was developed using computational techniques and the locations of the catalytic residues were identified. Results from this study for the first time highlighted Ser297 potentially

  15. Denitrification activity of the bacterium Pseudomonas sp. ASM-2-3 isolated from the Ariake Sea tideland.

    Science.gov (United States)

    Kariminiaae-Hamedaani, Hamid-Reza; Kanda, Kohzo; Kato, Fumio

    2004-01-01

    A new denitrifying bacterium strain ASM-2-3 was isolated from the Ariake Sea tideland, Japan. The isolate had the capability to fully remove as high as 225.8 mg nitrate-nitrogen.l(-1) under stationary culture conditions without accumulation of nitrite as an intermediate. From biochemical tests and 16S rDNA sequencing analysis, the genus of the bacterium was identified as Pseudomonas and close to stutzeri species. The nitrate removal efficiency of the isolate was faster than that of the control strain Pseudomonas stutzeri NBRC 14165, using succinate as the sole carbon source. The isolate could grow in up to 10% (w/v) of NaCl containing medium. The enzymatic tests showed that the activity of enzymes responsible for the reduction of nitrate and nitrite in strain ASM-2-3 was 1.4 and 2.3 times higher than that of the control strain. The feasibility of application of the isolate strain ASM-2-3 in a packed bed bioreactor was investigated for 40 d.

  16. Colonization of Potato Rhizosphere by GFP-Tagged Bacillus subtilis MB73/2, Pseudomonas sp. P482 and Ochrobactrum sp. A44 Shown on Large Sections of Roots Using Enrichment Sample Preparation and Confocal Laser Scanning Microscopy

    Directory of Open Access Journals (Sweden)

    Sylwia Jafra

    2012-12-01

    Full Text Available The ability to colonize the host plants’ rhizospheres is a crucial feature to study in the case of Plant Growth Promoting Rhizobacteria (PGPRs with potential agricultural applications. In this work, we have created GFP-tagged derivatives of three candidate PGPRs: Bacillus subtilis MB73/2, Pseudomonas sp. P482 and Ochrobactrum sp. A44. The presence of these strains in the rhizosphere of soil-grown potato (Solanum tuberosum L. was detected with a classical fluorescence microscope and a confocal laser scanning microscope (CLSM. In this work, we have used a broad-field-of-view CLMS device, dedicated to in vivo analysis of macroscopic objects, equipped with an automated optical zoom system and tunable excitation and detection spectra. We show that features of this type of CLSM microscopes make them particularly well suited to study root colonization by microorganisms. To facilitate the detection of small and scattered bacterial populations, we have developed a fast and user-friendly enrichment method for root sample preparation. The described method, thanks to the in situ formation of mini-colonies, enables visualization of bacterial colonization sites on large root fragments. This approach can be easily modified to study colonization patterns of other fluorescently tagged strains. Additionally, dilution plating of the root extracts was performed to estimate the cell number of MB73/2, P482 and A44 in the rhizosphere of the inoculated plants.

  17. Hydrolysis of carbaryl by a Pseudomonas sp. and construction of a microbial consortium that completely metabolizes carbaryl.

    Science.gov (United States)

    Chapalamadugu, S; Chaudhry, G R

    1991-03-01

    Two Pseudomonas spp. (isolates 50552 and 50581) isolated from soil degraded 1-naphthol and carbaryl, an N-methylcarbamate pesticide, respectively. They utilized these compounds as a sole source of carbon. 1-Naphthol was completely metabolized to CO2 by the isolate 50552, while the carbaryl was first hydrolyzed to 1-naphthol and then converted into a brown-colored compound by the isolate 50581. The colored metabolite was not degraded, but 1-naphthol produced by the isolate 50581 during the exponential phase of growth was metabolized by the isolate 50552. The two isolates were used to construct a bacterial consortium which completely catabolized carbaryl to CO2. No metabolite was detected in the cell cultures of the consortium. The isolate 50581 harbored a 50-kb plasmid pCD1, while no plasmid was detected in the isolate 50552. The isolated bacteria individually or as a consortium may be used for detoxification of certain industrial and agricultural wastes.

  18. APPLICATION OF PSEUDOMONAS PUTIDA AND RHODOCOCCUS SP. BY BIODEGRADATION OF PAH(S, PCB(S AND NEL SOIL SAMPLES FROM THE HAZARDOUS WASTE DUMP IN POZĎÁTKY (CZECH REPUBLIC

    Directory of Open Access Journals (Sweden)

    Radmila Kucerova

    2006-12-01

    Full Text Available The objective of the project was a laboratory check of biodegradation of soil samples contaminated by PAH(s, PCB(s and NEL from the hazardous waste dump in the Pozďátky locality. For the laboratory check, pure bacterial cultures of Rhodococcus sp. and Pseudomonas putida have been used. It is apparent from the laboratory experiments results that after one-month bacterial leaching, applying the bacterium of Rhodococcus sp. there is a 83 % removal of NEL, a 79 % removal of PAH(s and a 14 % removal of PCB(s. Applying a pure culture of Pseudomonas putida there is a 87 % removal of NEL, a 81 % removal of PAH(s and a 14 % removal of PCB(s.

  19. 深海适冷菌Pseudomonas sp.SM9913的适冷生长机制探讨%Preliminary Study on the Cold-adapted Growth Mechanism of a Deep-sea Psychrotrophic Strain Pseudomonas sp SM9913

    Institute of Scientific and Technical Information of China (English)

    陈秀兰; 张玉忠; 栾裼武; 高培基

    2002-01-01

    研究了温度对适冷菌Pseudomonas sp.SM9913的生长与适冷蛋白酶合成的影响,结果表明,P. sp.SM9913的最适生长温度为15 ℃,最适产酶温度为10 ℃, 是一典型的适冷菌.P. sp.SM9913分泌的适冷蛋白酶在低温下与底物的亲和力增大,反应的活化能 降低,表明在低温下较中温蛋白酶有更高的催化效率.深海产适冷蛋白酶的适冷菌P. SM9913可能是通过提高菌株在低温下的生长速率和增加酶分子在低温下的催化效率两条途径增加低温环境中蛋白质的分解效率,从而以适应低温环境.

  20. 内生菌Pseudomonas sp.G5 phzIR基因的克隆与表达%Cloning of phzIR from the endophytic Pseudomonas sp.G5 and its expression in Eschertcihta coli

    Institute of Scientific and Technical Information of China (English)

    李惠; 刘晓光; 高克祥; 贾金丽

    2009-01-01

    假单胞茵菌株G5是分离自香菜(Coriandrum sativum L.)茎内的一株内生菌,经BIOLOG系统分析其底物利用图谱,初步鉴定为桔黄假单胞茵Pseudomonas aurantiaca.大量研究已表明许多革兰氏阴性细菌应用群体感应系统,通过感应扩散性小信号分子一乙酰基高丝氨酸内酯(N-acyl homoserine lactones,AHLs),以种群密度依赖的方式调控基因表达.控制植物相关细菌的多种表型.本研究组合应用AHLs检测菌株Chromobacterium violaceum CV026和薄层层析分析, 初步检测出菌株G5可产生几种可检测水平的AHLs信号分子,其中以N-hexanoyl-homoserine lactone(C6-HSL,HHL)为主.迁移率Rf值为0.4.进一步克隆和测序了该菌株中由Phzl和PhzR组成的群体感应quorum sensing系统的编码基因PhzIR,并在大肠杆菌中异源表达了AHLs信号分子合成酶基因phzl.序列和系统进化分析表明它们与假单胞茵属其他的phzIR基因有高度同源性和进化上的保守性.

  1. Combined removal of a BTEX, TCE, and cis-DCE mixture using Pseudomonas sp. immobilized on scrap tyres.

    Science.gov (United States)

    Lu, Qihong; de Toledo, Renata Alves; Xie, Fei; Li, Junhui; Shim, Hojae

    2015-09-01

    The simultaneous aerobic removal of a mixture of benzene, toluene, ethylbenzene, and o,m,p-xylene (BTEX); cis-dichloroethylene (cis-DCE); and trichloroethylene (TCE) from the artificially contaminated water using an indigenous bacterial isolate identified as Pseudomonas plecoglossicida immobilized on waste scrap tyres was investigated. Suspended and immobilized conditions were compared for the removal of these volatile organic compounds. For the immobilized system, toluene, benzene, and ethylbenzene were completely removed, while the highest removal efficiencies of 99.0 ± 0.1, 96.8 ± 0.3, 73.6 ± 2.5, and 61.6 ± 0.9% were obtained for o-xylene, m,p-xylene, TCE, and cis-DCE, respectively. The sorption kinetics of contaminants towards tyre surface was also evaluated, and the sorption capacity generally followed the order of toluene > benzene > m,p-xylene > o-xylene > ethylbenzene > TCE > cis-DCE. Scrap tyres showed a good capability for the simultaneous sorption and bioremoval of BTEX/cis-DCE/TCE mixture, implying a promising waste material for the removal of contaminant mixture from industrial wastewater or contaminated groundwater.

  2. Kinetic analysis and bacterium metabolization of α-pinene by a novel identified Pseudomonas sp.strain

    Institute of Scientific and Technical Information of China (English)

    Zhuowei Cheng; Pengfei Sun; Yifeng Jiang; Lili Zhang; Jianmeng Chen

    2012-01-01

    Biodegradation has become a popular alternative remediation technology for its economic and ecological advantages.An aerobic bacterium (strain ZW) capable of degrading α-pinene was isolated from a biofilter by a selective enrichment.Based on the 16S rRNA gene analysis and physiochemical properties,this strain was identified as Pseudomonas veronii.Under the optimized condition achieved by the response surface methodology (RSM),as well as pH 6.82,temperature 26.3°C and NaCl concentration 1.36%,almost 100%α-pinene could be removed within 45 hr.Enzymatic biodegradation by the crude intracellular enzyme could be described well by the Michaelis-Menten model in which the maximum degradation rate Vmax and the half-saturation constant Km were calculated to be 0.431 mmol/(L.min) and 0.169 mmol/L,respectively.Activity assay of catechol suggested that the strain ZW possessed a catechol1,2-dioxygenase and could decompose benzene-ring through ortho ring cleavage.Based on the identified intermediates by GC/MS,a new metabolic pathway was proposed,in which the final metabolites were some simpler organic and inorganic compounds.The present work demonstrated that the strain ZW would have a great application prospect for the remediation of α-pinene-contaminated environment.

  3. Degradation of 2,4-dinitroanisole (DNAN) by metabolic cooperative activity of Pseudomonas sp. strain FK357and Rhodococcus imtechensis strain RKJ300.

    Science.gov (United States)

    Khan, Fazlurrahman; Pal, Deepika; Ghosh, Anuradha; Cameotra, Swaranjit Singh

    2013-11-01

    2,4-Dinitroanisole (DNAN) is an insensitive explosive ingredient used by many defense agencies as a replacement for 2,4,6-trinitrotoluene. Although the biotransformation of DNAN under anaerobic condition has been reported, aerobic microbial degradation pathway has not been elucidated. An n-methyl-4-nitroaniline degrading bacterium Pseudomonas sp. strain FK357 transformed DNAN into 2,4-dinitrophenol (2,4-DNP) as an end product. Interestingly, when strain FK357 was co-cultured with a 2,4-DNP degrading Rhodococcus imtechensis strain RKJ300, complete and high rate of DNAN degradation was observed with no accumulation of intermediates. Enzyme assay using cell extracts of strain FK357 demonstrated that O-demethylation reaction is the first step of DNAN degradation with formation of 2,4-DNP and formaldehyde as intermediates. Subsequently, 2,4-DNP was degraded by strain RKJ300 via the formation of hydride-Meisenheimer complex. The present study clearly demonstrates that complete degradation of DNAN occurs as a result of the metabolic cooperative activity of two members within a bacterial consortium.

  4. 产碱性脂肪酶菌株的筛选和培养%Screening and Culture of Alkaline Lipase-produced Strain Pseudomonas sp. ZJU-02

    Institute of Scientific and Technical Information of China (English)

    洪骏; 夏黎明

    2003-01-01

    以Rodamine B平板筛选法获得了一株高活力碱性脂肪酶产生菌Pseudomonas sp. ZJU+02.摇瓶产酶实验表明,适宜产酶培养基为(%):玉米浆3,植物油1, K2HPO4 0.1, KCl 0.05, MgSO4 0.05, Tween80 0.05;最佳培养条件为温度26℃、初始pH 6.5. 脂肪酶活力可高达86 IU/ml. 该酶在70℃以下、pH 7.0~10.5范围内稳定;酶反应的适宜温度为40℃,适宜pH为9.5. 该酶制剂在洗涤剂和制革工业中有良好的应用前景.

  5. Characterization of hydrocarbon-degrading and biosurfactant-producing Pseudomonas sp. P-1 strain as a potential tool for bioremediation of petroleum-contaminated soil.

    Science.gov (United States)

    Pacwa-Płociniczak, Magdalena; Płaza, Grażyna Anna; Poliwoda, Anna; Piotrowska-Seget, Zofia

    2014-01-01

    The Pseudomonas sp. P-1 strain, isolated from heavily petroleum hydrocarbon-contaminated soil, was investigated for its capability to degrade hydrocarbons and produce a biosurfactant. The strain degraded crude oil, fractions A5 and P3 of crude oil, and hexadecane (27, 39, 27 and 13% of hydrocarbons added to culture medium were degraded, respectively) but had no ability to degrade phenanthrene. Additionally, the presence of gene-encoding enzymes responsible for the degradation of alkanes and naphthalene in the genome of the P-1 strain was reported. Positive results of blood agar and methylene blue agar tests, as well as the presence of gene rhl, involved in the biosynthesis of rhamnolipid, confirmed the ability of P-1 for synthesis of glycolipid biosurfactant. 1H and 13C nuclear magnetic resonance, Fourier transform infrared spectrum and mass spectrum analyses indicated that the extracted biosurfactant was affiliated with rhamnolipid. The results of this study indicate that the P-1 and/or biosurfactant produced by this strain have the potential to be used in bioremediation of hydrocarbon-contaminated soils.

  6. Purification of low-concentration phenazine-1-carboxylic acid from fermentation broth of Pseudomonas sp. M18 via free flow electrophoresis with gratis gravity.

    Science.gov (United States)

    Shao, Jing; Fan, Liu-Yin; Zhang, Wei; Guo, Chen-Gang; Li, Si; Xu, Yu-Quan; Cao, Cheng-Xi

    2010-10-01

    The low-concentration phenazine-1-carboxylic acid (PCA) ( = 0.3 mM) extracted from fermentation broth of Pseudomonas sp. M18 was selected to be purified with a newly facile free flow electrophoresis (FFE) device with gratis gravity. Three factors of pH value and concentration of background buffer, and the cooling circle of FFE device were investigated for the purification of PCA in the FFE device. It was found that the pH value and concentration of background buffer had mild influences on the separation of PCA whether with cooling circle or not. However, the cooling circle had a much greater impact on the separation of PCA. The controlling of the band zone of PCA in FFE chamber would be difficult if without cooling circle, while the controlling would become easy if with cooling circle. Under the optimal conditions (10 mM pH 5.5 phosphate as background buffer, 30 mM pH 5.5 phosphate buffer as electrode solution, 5.46 mL/min background flux, 10 min residence time of injected sample, and 500 V), PCA could be continuously prepared from its impurities with relative high purity. The flux of sample injection was 115 μL/min, viz. 7 mL sample throughput per hour, and the recovery was up to 85%. All of the experiments indicated that the FFE technique was a good alternative tool for the study on natural biological control agents.

  7. para-Nitrophenol 4-monooxygenase and hydroxyquinol 1,2-dioxygenase catalyze sequential transformation of 4-nitrocatechol in Pseudomonas sp. strain WBC-3.

    Science.gov (United States)

    Wei, Min; Zhang, Jun-Jie; Liu, Hong; Zhou, Ning-Yi

    2010-11-01

    Pseudomonas sp. strain WBC-3 utilizes para-nitrophenol (PNP) as a sole source of carbon, nitrogen and energy. PnpA (PNP 4-monooxygenase) and PnpB (para-benzoquinone reductase) were shown to be involved in the initial steps of PNP catabolism via hydroquinone. We demonstrated here that PnpA also catalyzed monooxygenation of 4-nitrocatechol (4-NC) to hydroxyquinol, probably via hydroxyquinone. It was the first time that a single-component PNP monooxygenase has been shown to catalyze this conversion. PnpG encoded by a gene located in the PNP degradation cluster was purified as a His-tagged protein and identified as a hydroxyquinol dioxygenase catalyzing a ring-cleavage reaction of hydroxyquinol. Although all the genes necessary for 4-NC metabolism seemed to be present in the PNP degradation cluster in strain WBC-3, it was unable to grow on 4-NC as a sole source of carbon, nitrogen and energy. This was apparently due to the substrate's inability to trigger the expression of genes involved in degradation. Nevertheless, strain WBC-3 could completely degrade both PNP and 4-NC when PNP was used as the inducer, demonstrating its potential in bioremediation of the environment polluted by both 4-NC and PNP.

  8. Evaluation and elimination of inhibitory effects of salts and heavy metal ions on biodegradation of Congo red by Pseudomonas sp. mutant.

    Science.gov (United States)

    Gopinath, Kannappan Panchamoorthy; Kathiravan, Mathur Natarajan; Srinivasan, Raman; Sankaranarayanan, Subramanian

    2011-02-01

    In this study, it was attempted to evaluate the influences and also recommended some elimination methods for inhibitory effects offered by salts and heavy metal ions. Congo red dye solution treated with mutant Pseudomonas sp. was taken as a model system for study. The salts used in this study are NaCl, CaCl(2) and MgSO(4)· 7H(2)O. Though the growth was inhibited at concentrations above 4 g/l, toleration was achieved by acclimatization process. In case of heavy metal ions, Cr (VI) showed low inhibition up to 500 mg/l of concentration, compared to Zn (II) and Cu (II). It was due to the presence of chromium reductase enzyme which was confirmed by SDS-PAGE. Zn (II) and Cu (II) ion inhibitions were eliminated by chelation with EDTA. The critical ion concentrations obtained as per Han-Levenspiel model for Cr (VI), Zn (II) and Cu (II) were 0.8958, 0.3028 and 0.204 g/l respectively.

  9. Las-like quorum-sensing system negatively regulates both pyoluteorin and phenazine-1-carboxylic acid production in Pseudomonas sp. M18

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    A las-like quorum-sensing system in Pseudomonas sp. M18 was identified, which consisted of lasI and lasR genes encoding LuxI-LuxR type regulator. Several functions of the las system from strain M18 were investigated in this study. The chromosomal inactivation of either lasI or lasR by recombination increased the production of both pyoluteorin (Plt) and phenazine-1-carboxylic acid (PCA) by 4-5 fold and 2-3 fold over that of the wild type strain of M18, respectively. Production of both antibiotics was restored to wild-type levels after in trans complementation with the wild-type lasI or lasR gene. Expression of the translational fusions pltA’-’lacZ and phzA’-’lacZ further confirmed the negative effect of lasI or lasR on both biosynthetic operons, and it was also demonstrated that the las system was related to the ability of swarming motility and the inhibition of cell growth.

  10. Antipathogenic potential of marine Bacillus sp. SS4 on N-acyl-homoserine-lactone-mediated virulence factors production in Pseudomonas aeruginosa (PAO1)

    Indian Academy of Sciences (India)

    K Syed Musthafa; V Saroja; S Karutha Pandian; A Veera Ravi

    2011-03-01

    Antipathogenic therapy is an outcome of the quorum-sensing inhibition (QSI) mechanism, which targets autoinducer-dependent virulent gene expression in bacterial pathogens. -acyl homoserine lactone (AHL) acts as a key regulator in the production of virulence factors and biofilm formation in Pseudomonas aeruginosa PAO1 and violacein pigment production in Chromobacterium violaceum. In the present study, the marine bacterial strain SS4 showed potential QSI activity in a concentration-dependent manner (0.5–2 mg/ml) against the AHL-mediated violacein production in C. violaceum (33–86%) and biofilm formation (33–88%), total protease (20–65%), LasA protease (59–68%), LasB elastase (36–68%), pyocyanin (17–86%) and pyoverdin productions in PAO1. The light and confocal laser scanning microscopic analyses confirmed the reduction of the biofilm-forming ability of PAO1 when treated with SS4 extract. Furthermore, the antibiofilm potential was confirmed through static biofilm ring assay, in which ethyl acetate extract of SS4 showed concentration-dependent reduction in the biofilm-forming ability of PAO1. Thus, the result of this study clearly reveals the antipathogenic and antibiofilm properties of the bacterial isolate SS4. Through 16S rDNA analysis, the strain SS4 was identified as Bacillus sp. (GenBank Accession Number: GU471751).

  11. The structure of a calcium-dependent phosphoinositide-specific phospholipase C from Pseudomonas sp. 62186, the first from a Gram-negative bacterium.

    Science.gov (United States)

    Moroz, Olga V; Blagova, Elena; Lebedev, Andrey A; Nørgaard, Allan; Segura, Dorotea R; Blicher, Thomas H; Brask, Jesper; Wilson, Keith S

    2017-01-01

    Bacterial phosphoinositide-specific phospholipases C (PI-PLCs) are the smallest members of the PI-PLC family, which includes much larger mammalian enzymes responsible for signal transduction as well as enzymes from protozoan parasites, yeast and plants. Eukaryotic PI-PLCs have calcium in the active site, but this is absent in the known structures of Gram-positive bacteria, where its role is instead played by arginine. In addition to their use in a number of industrial applications, the bacterial enzymes attract special interest because they can serve as convenient models of the catalytic domains of eukaryotic enzymes for in vitro activity studies. Here, the structure of a PI-PLC from Pseudomonas sp. 62186 is reported, the first from a Gram-negative bacterium and the first of a native bacterial PI-PLC with calcium present in the active site. Solution of the structure posed particular problems owing to the low sequence identity of available homologous structures. Its dependence on calcium for catalysis makes this enzyme a better model for studies of the mammalian PI-PLCs than the previously used calcium-independent bacterial PI-PLCs.

  12. Biofilm formation and disinfectant resistance of Salmonella sp. in mono- and dual-species with Pseudomonas aeruginosa.

    Science.gov (United States)

    Pang, X Y; Yang, Y S; Yuk, H G

    2017-09-01

    This study aimed to evaluate the biofilm formation and disinfectant resistance of Salmonella cells in mono- and dual-species biofilms with Pseudomonas aeruginosa, and to investigate the role of extracellular polymeric substances (EPS) in the protection of biofilms against disinfection treatment. The populations of Salmonella in mono- or dual-species biofilms with P. aeruginosa on stainless steel (SS) coupons were determined before and after exposure to commercial disinfectant, 50 μg ml(-1) chlorine or 200 μg ml(-1) Ecolab(®) Whisper™ V (a blend of four effective quaternary ammonium compounds (QAC)). In addition, EPS amount from biofilms was quantified and biofilm structures were observed using scanning electron microscopy (SEM). Antagonistic interactions between Salmonella and P. aeruginosa resulted in lower planktonic population level of Salmonella, and lower density in dual-species biofilms compared to mono-species biofilms. The presence of P. aeruginosa significantly enhanced disinfectant resistance of S. Typhimurium and S. Enteritidis biofilm cells for 2 days, and led to an average of 50% increase in polysaccharides amount in dual-species biofilms than mono-species biofilms of Salmonella. Microscopy observation showed the presence of large microcolonies covered by EPS in dual-species biofilms but not in mono-species ones. The presence of P. aeruginosa in dual-species culture inhibited the growth of Salmonella cells in planktonic phase and in biofilms, but protected Salmonella cells in biofilms from disinfection treatment, by providing more production of EPS in dual-species biofilms than mono-species ones. This study provides insights into inter-species interaction, with regard to biofilm population dynamics and disinfectant resistance. Thus, a sanitation protocol should be designed considering the protective role of secondary species to pathogens in biofilms on SS surface which has been widely used at food surfaces and manufacturers. © 2017 The

  13. Characterization of a Pseudomonas putida rough variant evolved in a mixed species biofilm with Acinetobacter sp. strain C6

    DEFF Research Database (Denmark)

    Hansen, Susse Kirkelund; Haagensen, Janus Anders Juul; Gjermansen, Morten

    2007-01-01

    biosynthesis. Here we investigate further the biofilm physiology and the phenotypic characteristics of the selected P. putida rough colony variants. The coexistence of the P. putida population in a mixed-species biofilm with Acinetobacter sp. strain C6 is dependent on the benzoate excreted from Acinetobacter...... was shown to evolve rapidly by natural selection of better-adapted variants in a mixed-species biofilm consortium (S. K. Hansen, P. B. Rainey, J. A. Haagensen, and S. Molin, Nature 445:533-536, 2007). Adaptation was caused by mutations in a wapH homolog (PP4943) involved in core lipopolysaccharide...... during the catabolism of benzyl alcohol, the sole carbon source. Examination of biofilm development and the dynamics of the wild-type consortium revealed that the biofilm environment became oxygen limited, possibly with low oxygen concentrations around Acinetobacter microcolonies. In contrast to P...

  14. Evaluación de cepas de Pseudomonas sp para el control de hongos fitopatógenos que afectan cultivos de interés económico

    Directory of Open Access Journals (Sweden)

    Pilar M. Villa

    2005-01-01

    Full Text Available Se promueve cada vez más disminuir el uso de los plaguicidas químicos que afectan al ecosistema, para lo cual se emplean diferentes alternativas entre las que se encuentra el control biológico con microorganismos o sus metabolitos entre los que se encuentran las Pseudomonas fluorescentes por las propiedades que presentan. El objetivo de este trabajo es la evaluación de cepas de Pseudomonas de la Colección de Cultivos del ICIDCA para ser empleadas en el control biológico que afectan cultivos de interés económico. Se evaluaron 7 cepas que producen sideróforos y metabolitos antimicrobianos frente al hongo Sclerotium rolfsii mediante cultivo dual en papa dextrosa Agar más King B y Agar Nutriente, determinando la inhibición del crecimiento micelial del hongo. Se observó que las 7 cepas inhiben el crecimiento de éste entre el 60 y 90 % por la producción de sideróforos y compuestos antibióticos lo que las hacen efectiva para el control biológico. Las mejores cepas fueron las cepas de las Pseudomonas sp. 13 y las Pseudomonas aeruginosa PSS, y 11, que las hace promisorias para el desarrollo de productos biológicos para el control de enfermedades fúngicas en cultivos de interés económico.

  15. Isolation and Characterization of Electrochemical Active Bacterial Pseudomonas aeruginosa Strain RE7%1株产电假单胞菌(Pseudomonas sp.)RE7的分离及特性研究

    Institute of Scientific and Technical Information of China (English)

    骆海萍; 刘广立; 张仁铎; 曹理想

    2009-01-01

    微生物燃料电池(microbial fuel cell,MFC)阳极微生物的种类和作用机制对MFC的产电性能有着重要的影响.从已稳定运行1 a的MFC的阳极室分离得到1株电化学活性革兰氏阴性细菌--菌株RE7,其16S rRNA基因序列与Pseudomonas aeruginosa strain CMG 587有99%同源性,属于假单胞菌属(Pseudomonas sp.).利用菌株RE7构建的MFC的稳定产电和循环伏安曲线测定结果都表明,菌株RE7具有较强的电化学活性,利用菌株RE7构建的MFC的最大输出电压为352 mV,相应的最大面积功率密度为69.2 mW/m~2,体积最大功率密度为6.2 W/m~3.由不同稀释比例的MFC排出液的产电效果比较可知,菌株RE7极有可能是通过自身分泌的氧化还原类物质进行电子传递.%Microbial components of the microbial fuel cells (MFCs) , including species constitution and metabolic mechanism of the anodic microorganisms,are critical to the optimization of electricity generation. An clcctrogenesis bacterium strain (designated as RE7) was isolated from an MFC that had been running in a fed batch mode for over one year. The isolate was identified as a strain of Pseudmrwnas aeruginosa based on its physiological, morphological characteristics and 16S rRNA sequence analysis. Direct electron transfer from RE7 to an electrode was examined using cyclic voltammetry and MFC. Results of both methods showed the electrochemical activity of the bacterium without any electrochemical mediator. The P. aeruginosa strain RE7 was inoculated into the anode chamber of a packing- type MFC and the maximal voltage output was 352 mV with 1 500 mg/L glucose as the fuel. Correspondingly, the maximal area and volumetric power densities were 69.2 mW/m~2 and 6.2 W/m , respectively. Bacteria-producing soluble redox mediators, such as phenazine derivatives, are possible mechanism to facilitate the direct electron transfer to the electrode from the bacteria] cells.

  16. Isolation and characterization of a novel paraffin wax-degrading bacterium, Pseudomonas sp strain PW-1, from petroleum-contaminated sites.

    Science.gov (United States)

    Zhang, Y L; Liu, Z; Liu, T

    2016-06-10

    An isolate capable of degrading paraffin wax was isolated from petroleum-contaminated sites in Daqing, China, and identified as Pseudomonas sp strain PW-1 by analyzing the 16S rDNA sequence (GenBank accession No.: KF529529) as well as the biochemical and physiological characteristics. The optimized degradation conditions of the isolate were as follows: FeSO4 metal ion concentration of 0.01 g, temperature of 30°C, (NH4)2SO4 nitrogen source concentration of 1.5 g/L, and a carbon: nitrogen ratio of 10:1. Response surface methodology-based analysis of the culture time, inoculation amount, and initial pH of the medium revealed that the optimal theoretical conditions were a culture time of 11.16 days, inoculation amount of 3.13%, and an initial pH of 9.29. The theoretical degradation rate was up to 54.68% under the optimal conditions. Taking into account the experimental conditions of a laboratory, 11.2 days of cultivating time, 3% inoculum, and a medium initial pH of 9.3 were used in practical settings. Experimental results showed that the degradation rate of paraffin wax was 52.85%, which demonstrated that this strain could degrade 1050 mg paraffin wax, using it as the sole carbon source, in a 1000-mL minimal salts medium. These results indicate that the strain PW1 can be used for application in oil wells with paraffin deposition problems in order to enhance oil recovery.

  17. Biosorption of the metal-complex dye Acid Black 172 by live and heat-treated biomass of Pseudomonas sp. strain DY1: Kinetics and sorption mechanisms

    Energy Technology Data Exchange (ETDEWEB)

    Du, Lin-Na; Wang, Bing [College of Life Science, Zhejiang University, 310058, Hangzhou, Zhejiang Province (China); Li, Gang [Department of Agriculture and Biotechnology, Wenzhou Vocational College of Science and Technology, 325006 Wenzhou, Zhejiang Province (China); Wang, Sheng [College of Life Science, Zhejiang University, 310058, Hangzhou, Zhejiang Province (China); Crowley, David E., E-mail: crowley@ucr.edu [Department of Environmental Science, University of California, Riverside, CA 92521 (United States); Zhao, Yu-Hua, E-mail: yhzhao225@zju.edu.cn [College of Life Science, Zhejiang University, 310058, Hangzhou, Zhejiang Province (China)

    2012-02-29

    Highlights: Black-Right-Pointing-Pointer The maximum amount of Acid Black 172 sorption was about 2.98 mmol/g biomass. Black-Right-Pointing-Pointer Amine groups played a major role in the biosorption of Acid Black 172. Black-Right-Pointing-Pointer The reasons of increased dye sorption by heat-treated biomass were proposed. - Abstract: The ability of Pseudomonas sp. strain DY1 to adsorb Acid Black 172 was studied to determine the kinetics and mechanisms involved in biosorption of the dye. Kinetic data for adsorption fit a pseudo-second-order model. Increased initial dye concentration could significantly enhance the amount of dye adsorbed by heat-treated biomass in which the maximum amount of dye adsorbed was as high as 2.98 mmol/g biomass, whereas it had no significant influence on dye sorption by live biomass. As treated temperature increased, the biomass showed gradual increase of dye sorption ability. Experiments using potentiometric titration and Fourier transform infrared spectroscopy (FTIR) indicated that amine groups (NH{sub 2}) played a prominent role in biosorption of Acid Black 172. Scanning electron microscopy (SEM), atomic force microscopy (AFM) and transmission electron microscopy (TEM) analysis indicated that heat treatment of the biomass increased the permeability of the cell walls and denatured the intracellular proteins. The results of biosorption experiments by different cell components confirmed that intracellular proteins contributed to the increased biosorption of Acid Black 172 by heat-treated biomass. The data suggest that biomass produced by this strain may have application for removal of metal-complex dyes from wastewater streams generated from the dye products industry.

  18. Tuning the specificity of the recombinant multicomponent toluene o-xylene monooxygenase from Pseudomonas sp. strain OX1 for the biosynthesis of tyrosol from 2-phenylethanol.

    Science.gov (United States)

    Notomista, Eugenio; Scognamiglio, Roberta; Troncone, Luca; Donadio, Giuliana; Pezzella, Alessandro; Di Donato, Alberto; Izzo, Viviana

    2011-08-01

    Biocatalysis is today a standard technology for the industrial production of several chemicals, and the number of biotransformation processes running on a commercial scale is constantly increasing. Among biocatalysts, bacterial multicomponent monooxygenases (BMMs), a diverse group of nonheme diiron enzymes that activate dioxygen, are of primary interest due to their ability to catalyze a variety of complex oxidations, including reactions of mono- and dihydroxylation of phenolic compounds. In recent years, both directed evolution and rational design have been successfully used to identify the molecular determinants responsible for BMM regioselectivity and to improve their activity toward natural and nonnatural substrates. Toluene o-xylene monooxygenase (ToMO) is a BMM isolated from Pseudomonas sp. strain OX1 which hydroxylates a wide spectrum of aromatic compounds. In this work we investigate the use of recombinant ToMO for the biosynthesis in recombinant cells of Escherichia coli strain JM109 of 4-hydroxyphenylethanol (tyrosol), an antioxidant present in olive oil, from 2-phenylethanol, a cheap and commercially available substrate. We initially found that wild-type ToMO is unable to convert 2-phenylethanol to tyrosol. This was explained by using a computational model which analyzed the interactions between ToMO active-site residues and the substrate. We found that residue F176 is the major steric hindrance for the correct positioning of the reaction intermediate leading to tyrosol production into the active site of the enzyme. Several mutants were designed and prepared, and we found that the combination of different mutations at position F176 with mutation E103G allows ToMO to convert up to 50% of 2-phenylethanol into tyrosol in 2 h.

  19. 海洋 Pseudomonas aeruginosa sp.DES-3的鉴定以及基因ap02对其产蛋白酶的影响研究%Identification of a Pseudomonas aeruginosa sp.DES-3 From Marine and the Effect of Protease-producing by a Gene of ap 02

    Institute of Scientific and Technical Information of China (English)

    刘瑶; 陈俊海; 肖桂龙; 孟灿; 曾蓉; 武波; 蒋承建

    2016-01-01

    海洋是地球上最大的生态系统,其多样独特的生态环境造就了其有别于其他环境的微生物资源。本研究利用蛋白酶的活性筛选策略,从辽宁省营口市某海洋淤泥中分离得到一株产蛋白酶的优势菌株 DES-3。通过微生物形态学特征、生理生化性质和16S rDNA 基因鉴定以及系统发育进化关系的分析,将该菌株鉴定为铜绿假单胞菌属,命名为 Pseudomonas aeruginosa sp.DES-3。其胞外蛋白酶的最适反应温度和最适 pH 分别为55℃和9.0。将来自于碱性污染土壤宏基因组文库的编码碱性蛋白酶基因 ap 02与广宿主表达载体 pBBR1MCS-5连接,转化至野生型菌株 P .aeruginosa sp.DES-3细胞中,成功构建了基因工程菌株 P .aeruginosa sp.DES-3/pBBR1MCS-5-ap 02。基因工程菌株的最适反应温度为60℃,较野生型菌株提高了5℃。本研究构建基因工程菌株的策略可为菌株的改造和相应工业应用提供一定的技术参考。%Ocean is the largest ecosystem on the earth,and the microbial resources in the marine environ-ment are significantly different from the others natural eco-systems.In this study,a protease-producing strain DES-3 was obtained by using functional screening strategy from the marine sludge in Yingkou city, Liaoning Province of China.The DES-3 strain was identified as the genus of P seudomonas aeruginosa and named as P seudomonas aeruginosa sp.DES-3 based on the results of microbial morphological characteriza-tion,physiological and biochemical properties,and 1 6S rDNA gene identification and phylogenetic tree a-nalysis.The optimal temperature and pH of the purified protease were 55 ℃ and 9.0,respectively.Fur-thermore,an ap 02 gene encoding alkaline protease identified from an alkaline polluted soil metagenomics library,was ligated into a widely host expression vector of pBBR1MCS-5 and transferred into the competi-tion cells of P seudomonas aeruginosa sp.DES-3.Finally,a genetically engineered

  20. Pseudomonas saudiphocaensis’ sp. nov., a new bacterial species isolated from currency notes collected during the Hajj pilgrimage in 2012 at Makkah, Saudi Arabia

    Directory of Open Access Journals (Sweden)

    E.I. Azhar

    2017-01-01

    Full Text Available We report here the main characteristics of ‘Pseudomonas saudiphocaensis’ strain 20_BNT (CSUR P1224, a new species of the Pseudomonas genus that was isolated from currency notes collected during the Hajj pilgrimage in 2012 at Makkah, Saudi Arabia.

  1. Sulfur source-mediated transcriptional regulation of the rhlABC genes involved in biosurfactants production by Pseudomonas sp. strain AK6U.

    Science.gov (United States)

    Ismail, Wael; El Nayal, Ashraf M; Ramadan, Ahmed R; Abotalib, Nasser

    2014-01-01

    Despite the nutritional significance of sulfur, its influence on biosurfactants production has not been sufficiently studied. We investigated the expression of key biosurfactants production genes, rhlABC, in cultures of Pseudomonas sp. AK6U grown with inorganic or organic sulfur sources. AK6U grew with either inorganic sulfate (MgSO4), dibenzothiophene (DBT), or DBT-sulfone as a sole sulfur source in the presence of glucose as a carbon source. The AK6U cultures produced variable amounts of biosurfactants depending on the utilized sulfur source. Biosurfactants production profile of the DBT cultures was significantly different from that of the DBT-sulfone and inorganic sulfate cultures. The last two cultures were very similar in terms of biosurfactants productivity. Biosurfactants yield in the DBT cultures (1.3 g/L) was higher than that produced by the DBT-sulfone (0.5 g/L) and the inorganic sulfate (0.44 g/L) cultures. Moreover, the surface tension reduction in the DBT cultures (33 mN/m) was much stronger than that measured in the DBT-sulfone (58 mN/m) or inorganic sulfate (54 mN/m) cultures. RT-qPCR revealed variations in the expression levels of the rhlABC genes depending on the sulfur source. The DBT cultures had higher expression levels for the three genes as compared to the DBT-sulfone and inorganic sulfate cultures. There was no significant difference in the expression profiles between the DBT-sulfone and the MgSO4 cultures. The increased expression of rhlC in the DBT cultures is indicative for production of higher amounts of dirhamnolipids compared to the DBT-sulfone and inorganic sulfate cultures. The gene expression results were in good agreement with the biosurfactants production yields and surface tension measurements. The sulfur source mediates a fine-tuned mechanism of transcriptional regulation of biosurfactants production genes. Our findings can have an impact on industrial production of biosurfactants and other biotechnological processes like

  2. Pseudomonas fluorescens associated with Bacterial Disease in Catla catla in Marathwada Region of Maharashtra

    Directory of Open Access Journals (Sweden)

    1Omprakash Darak

    2015-05-01

    Full Text Available In the present study a detailed analysis was carried out to evaluate the association of various bacterial pathogens with Catla catla from Marathwada region of Maharashtra. The freshwater fishes were collected from different water bodies and fish culturing centre of eight districts of Marathwada region viz. Aurangabad, Jalna, Parbhani, Nanded, Hingoli, Latur, Beed and Osmanabad. The analysis could yield thirteen pathogenic bacteria from the fish samples that included Micrococcus sp., Bacillus sp., Lactobacillus sp., Vibrio sp., Aeromonas sp., Streptococcussp., Flavobacterium sp., Vibrio sp., Proteus sp., Staphylococcus sp., Enterobacteria sp., E.coli , Pseudomonas sp. The bacterial strains were identified based on colony morphology, cell morphology and biochemical chemical characters. The dominant bacterial pathogen was Pseudomonas sp. The Pseudomonas sp associated with Catla catla could survive on host as well as in water. Pseudomonas fluorescens was very sensitive to Kanamycin, Nalidixic acid, Gentamicin and Neomycin, less sensitive to tetracycline, amikacin and Chlorophenicol and very less sensitive to Oxytetracycline, Erythromycin and Penicillin.

  3. Purification of D-hydantoinase from Pseudomonas 2262%一株假单胞杆菌(Pseudomonas sp.)中D-海因酶的分离纯化

    Institute of Scientific and Technical Information of China (English)

    石亚伟; 李汉卿; 袁静明; 丁玉华; 连惠勇; 齐延红

    2001-01-01

    菌体经超声波处理后,上清液首先用热变性作为纯化的第一步,后经硫酸铵沉淀和Q-Sepharose fast flow阴离子交换柱,Phenyl-Sepharose fast flow疏水层析,Superose12凝胶排阻层析等步骤,从Pseudomonas 2262菌体中获得电泳纯的海因酶,酶活力回收15.6%,比活为18.37U/mg,提纯倍数为59.3.

  4. Reclassification of Alcaligenes latus strains IAM 12599T and IAM 12664 and Pseudomonas saccharophila as Azohydromonas lata gen. nov., comb. nov., Azohydromonas australica sp. nov. and Pelomonas saccharophila gen. nov., comb. nov., respectively.

    Science.gov (United States)

    Xie, Cheng-Hui; Yokota, Akira

    2005-11-01

    The aim of this study was to clarify the taxonomic position of the nitrogen-fixing and hydrogen-oxidizing bacteria Alcaligenes latus strains IAM 12599T, IAM 12664 and IAM 12665 and Pseudomonas saccharophila IAM 14368T. It was found that the type strain of Alcaligenes latus, IAM 12599T, showed 99 x 9 and 96 x 1 % 16S rRNA gene sequence similarity to strains IAM 12665 and IAM 12664, respectively. A comparison using DNA-DNA hybridization suggested that strains IAM 12599T and IAM 12665 belong to a single species (89 x 7 %) and that strain IAM 12664 (35 x 1 %) forms a separate species. The phenotypic characteristics also support the conclusion that these bacteria should be identified as two species of a new genus: Azohydromonas lata gen. nov., comb. nov. (type strain IAM 12599T=DSM 1122T=LMG 3321T=ATCC 29712T; reference strain IAM 12665=DSM 1123=LMG 3325=ATCC 29714) and Azohydromonas australica sp. nov. (type strain IAM 12664T=DSM 1124T=LMG 3324T=ATCC 29713T). Pseudomonas saccharophila IAM 14368T was found to be closely related to the phototrophic bacterium Roseateles depolymerans, with 96 x 8 % 16S rRNA gene sequence similarity, but the two bacteria are quite different with respect to their metabolism and some significant phenotypic characteristics, suggesting that they cannot be included in a single genus. Further studies on their nifH gene sequences, G+C content of the DNA and cellular fatty acid composition confirm that Pseudomonas saccharophila should be reclassified: the name Pelomonas saccharophila gen. nov., comb. nov. is proposed, with the type strain IAM 14368T (=LMG 2256T=ATCC 15946T).

  5. The ppuI-rsaL-ppuR quorum-sensing system regulates cellular motility, pectate lyase activity, and virulence in potato opportunistic pathogen Pseudomonas sp. StFLB209.

    Science.gov (United States)

    Kato, Taro; Morohoshi, Tomohiro; Someya, Nobutaka; Ikeda, Tsukasa

    2015-01-01

    Pseudomonas sp. StFLB209 was isolated from potato leaf as an N-acylhomoserine lactone (AHL)-producing bacterium and showed a close phylogenetic relationship with P. cichorii, a known plant pathogen. Although there are no reports of potato disease caused by pseudomonads in Japan, StFLB209 was pathogenic to potato leaf. In this study, we reveal the complete genome sequence of StFLB209, and show that the strain possesses a ppuI-rsaL-ppuR quorum-sensing system, the sequence of which shares a high similarity with that of Pseudomonas putida. Disruption of ppuI results in a loss of AHL production as well as remarkable reduction in motility. StFLB209 possesses strong pectate lyase activity and causes maceration on potato tuber and leaf, which was slightly reduced in the ppuI mutant. These results suggest that the quorum-sensing system is well conserved between StFLB209 and P. putida and that the system is essential for motility, full pectate lyase activity, and virulence in StFLB209.

  6. Isolation and Identification a Strain of Pseudomonas sp.QLD-9 and Its Biodegradation of Quinoline%假单胞菌QLD-9的分离鉴定及其对喹啉的生物降解

    Institute of Scientific and Technical Information of China (English)

    朱希坤; 王芳; 李小明; 胥维昌

    2012-01-01

    [Methods] Quinoline-degrading bacteria were isolated from contaminated soil by using enrichment culture method. [Results] A bacterial strain QLD-9 of utilizing quinoline as its sole nitrogen source and utilizing glucose as the carbon source was obtained. The strain was identified as Pseudomonas sp. according to the results of 16S rDNA sequence analysis. The strain could keep excellent degradation activity to quinoline with a concentration under 600 mg/L, and above 99.9% of quinoline with a concentration of 300 mg/L could be degraded within 48 h. [Conclusions] Strain QLD-9 showed potential of application for bio-remediation to quinoline in environment.%[方法]采用富集培养法从受杂环类污染的土壤中分离喹啉降解菌株.[结果]分离得到1株以喹啉为唯一氮源、葡萄糖为碳源生长的QLD-9菌株,经16S rDNA鉴定为假单胞菌属(Pseudomonas sp.),该菌株能在48 h内将300 mg/L的喹啉降解99.9%以上,对600 mg/L以内喹啉具有良好的降解效果.[结论]QLD-9菌株对环境中喹啉的生物修复具有很好的应用潜力.

  7. The draft genome sequence of multidrug-resistant Pseudomonas aeruginosa strain CCBH4851, a nosocomial isolate belonging to clone SP (ST277) that is prevalent in Brazil

    Science.gov (United States)

    Silveira, Melise; Albano, Rodolpho; Asensi, Marise; Assef, Ana Paula Carvalho

    2014-01-01

    The high occurrence of nosocomial multidrug-resistant (MDR) microorganisms is considered a global health problem. Here, we report the draft genome sequence of a MDR Pseudomonas aeruginosa strain isolated in Brazil that belongs to the endemic clone ST277. The genome encodes important resistance determinant genes and consists of 6.7 Mb with a G+C content of 66.86% and 6,347 predicted coding regions including 60 RNAs. PMID:25466623

  8. The draft genome sequence of multidrug-resistant Pseudomonas aeruginosa strain CCBH4851, a nosocomial isolate belonging to clone SP (ST277 that is prevalent in Brazil

    Directory of Open Access Journals (Sweden)

    Melise Silveira

    2014-12-01

    Full Text Available The high occurrence of nosocomial multidrug-resistant (MDR microorganisms is considered a global health problem. Here, we report the draft genome sequence of a MDR Pseudomonas aeruginosa strain isolated in Brazil that belongs to the endemic clone ST277. The genome encodes important resistance determinant genes and consists of 6.7 Mb with a G+C content of 66.86% and 6,347 predicted coding regions including 60 RNAs.

  9. Determinación de aislados nativos de pseudomonas desulfurizadoras mediante el estudio del perfil de ácidos grasos

    Directory of Open Access Journals (Sweden)

    Edilberto Silva Gómez

    2010-09-01

    Full Text Available Utilizando CGAR se determinó el contenido de ácidos grasos celulares de doce aislados colombianos, Pseudomonas aeruginosa 17, 18, 19, 20, 21, 22 y 103, Pseudomonas sp 23, 24, 25, 26 y 27 con capacidad desulfurizadora, Pseudomonas aeruginosa ATCC 9027 y 10145, Pseudomonas sp ATCC 39327 y Pseudomonas flúores cens. Se encontraron 53 ácidos grasos diferentes, entre saturados e insaturados de cadena lineal, y principalmente hidroxiácidos y ramificados.

  10. Pseudomonas - Fact Sheet

    OpenAIRE

    Public Health Agency

    2012-01-01

    Fact sheet on Pseudomonas, including:What is Pseudomonas?What infections does it cause?Who is susceptible to pseudomonas infection?How will I know if I have pseudomonas infection?How can Pseudomonas be prevented from spreading?How can I protect myself from Pseudomonas?How is Pseudomonas infection treated?

  11. Use of an algD promoter-driven expression system for the degradation of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) by Pseudomonas sp. HK-6.

    Science.gov (United States)

    Lee, Bheong-Uk; Baek, Hyun; Oh, Kye-Heon

    2013-10-01

    Pseudomonas sp. HK-6 is able to utilize hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) as a sole nitrogen source. The HK-6 strain was stimulated to produce an exopolymer, mainly alginate, as a stress response when grown in LB broth containing RDX, synthesizing ~230 μg/mL after 48 h. The algA mRNA levels in HK-6 increased by 7-8-fold after 2-6 h of exposure to 0.1 mM RDX, as measured by RT-qPCR. HK-6 was able to degrade ~25 % of 0.1 mM RDX after 20 days and 60 % after 50 days, whereas the pnrB null mutant only degraded less than 1 % after 50 days. The introduction of an algD promoter-pnrB gene fusion into the pnrB mutant fully restored RDX-degradation capability. To facilitate a study of PnrB action on RDX, a His6-PnrB fusion protein was heterologously expressed in E. coli BL21 cells, and the enzymatic activity on RDX was assayed by measuring the decrease in absorbance at 340 nm due to NADH oxidation. At the fixed condition of 0.1 mM RDX, 0.2 mM NADH, and 1 μg His6-PnrB, the absorbance at 340 nM gradually decreased and reached to its minimum value after 30 min. However, calculating the V max and K m values of PnrB for RDX was challenging due to extremely low solubility of RDX in water. The results clearly indicate the potential use of the algD promoter in studies of some genes in Pseudomonas species.

  12. Bioremediation of chlorothalonil-contaminated soil by utilizing Pseudomonas sp.strain CTN-3%假单胞菌菌株CTN-3对百菌清污染土壤的生物修复

    Institute of Scientific and Technical Information of China (English)

    王光利; 陈宏宏; 毕萌; 李顺鹏

    2012-01-01

    Chlorothalonil is the priority organic pollutant listed by the U. S. Environmental Protection Agency. To utilize the function of microbial degradation in the bioremediation of chlorothalonil-contaminated soil is of practical significance. In this study, a chlorothalonil-degrading Pseudomonas sp. strain CTN-3 isolated from pesticide-contaminated soil was used to examine the chlorothalonil-degrading capacity of the strain and related affecting factors in a microcosm. In sterilized soil, the effect of CTN-3 on chlorothalonil degradation was better than that in unsterilized soil. Various factors, including soil pH, temperature, initial chlorothalonil concentration, and inoculum size, affected the degradation of chlorothalonil by the strain. With the inoculum size of 10 CFU · g-1soil, the CTN-3 at 15-30 ℃ and pH 5. 8-8. 3 could effectively degrade 10-200 mg · kg-1 of chlorothalonil, suggesting that the strain CTN-3 had great potential in the bioremediation of chlorothalonil-contaminated soil.%百菌清被美国环境保护署列为优先控制污染物,利用微生物的降解作用修复被污染的土壤、清除环境中的污染物等具有重要的现实意义.假单胞菌(Pseudomonas sp.)菌株CTN-3是一株从污染土壤中分离得到的百菌清降解菌,考察了其在实验室条件下对百菌清污染土壤的生物修复能力及其影响因素.结果表明:降解菌株在灭菌土壤中的降解效果略好于未灭菌土壤;在外源添加降解菌106 CFU·g-1、温度15 ~ 30℃和pH5.8~8.3条件下,该菌株能有效降解土壤中10 ~200 mg·kg-1的百菌清.菌株CTN-3在百菌清污染土壤的生物修复中具有良好的应用前景.

  13. Binding of Pu(IV) to galacturonic acid and extracellular polymeric substances (EPS) from Shewanella putrefaciens, Clostridium sp. and Pseudomonas fluorescens

    Energy Technology Data Exchange (ETDEWEB)

    Harper, R.M. [Dept. of Environmental Sciences, Huxley Coll. of the Environment, Western Washington Univ., WA (United States); Kantar, C. [Dept. of Environmental Engineering, Mersin Univ., Ciftllikkoy, Mersin (Turkey); Honeyman, B.D. [Environmental Science and Engineering Div., Colorado School of Mines, Golden, CO (United States)

    2008-07-01

    The conditional stability constants for trace-level concentrations of Pu(IV) complexing with galacturonic acid and EPS, isolated from axenic Clostridium sp., P. fluorescens and Shewanella putrefaciens CN32 cultures, were determined at pH 4 and an ionic strength of 0.1 M NaCl using an ion-exchange technique. The analysis of ion-exchange data with Schubert's technique indicates that the Pu binding by galacturonic acid and EPS from Clostridium sp. and S. putrefaciens can be described based on the formation of 1: 1 Pu(IV)-ligand complexes. However, the accurate description of Pu binding by EPS from P. fluorescens requires postulation of a mixture of 1: 1/1: 2 complexes between Pu(IV) and ligands under the experimental conditions studied. The results from the ion-exchange experiments were also modeled based on a non-electrostatic, discrete ligand approach in which bacterial EPS is conceptualized as being composed of a suite of monoprotic acids, HL{sub 1}, of arbitrarily-assigned pK{sub a} (i) values (e.g., 4, 6 and 8). The examination of ion-exchange data in a chemical model suggested that only the pK{sub a} 4 (L{sub 1}) and 6 (L{sub 2}) ligands are sufficient to accurately simulate the Pu(IV)/EPS binding, implying that carboxylic groups in EPS are the primary binding sites for complexing with Pu(IV) under the experimental conditions examined. The affinity of EPS for complexing Pu(IV) decreases in the order of Clostridium sp. > S. putrefaciens > P. fluorescens although the concentrations of carboxylic groups in EPS decrease in the order of P. fluorescens > S. putrefaciens > Clostridium sp. This discrepancy may be due to differences in binding affinities between Na{sup +} ion in solution and EPS ligands. At I = 0.1 M, models demonstrated that the EPS from P. fluorescens exhibits a much stronger affinity for the Na{sup +} ion compared to ligands from other EPS; therefore, the deprotonated carboxylic sites of EPS from P. fluorescens are hypothesized to be mostly bound

  14. Control biológico del marchitamiento vascular causado por Fusarium oxysporum f. sp. phaseoli en fríjol Phaseolus vulgaris L., mediante la acción combinada de Entrophospora colombiana, Trichoderma sp. Y Pseudomonas fluorescens

    Directory of Open Access Journals (Sweden)

    Avendaño Camila

    2006-06-01

    Hidden="false" UnhideWhenUsed="false" QFormat="true" Name="Intense Emphasis" /> Entrophospora colombiana, Trichoderma sp., Pseudomonas fluorescens y una combinación de estos antagonistas fueron evaluados como biocontroladores de Fusarium oxysporumf. sp. Phaseoli en plantas de fríjol de la variedad ‘ICA Tundama’. El ensayo se estableció en una casa de malla del Programa nacional de manejo integrado de plagas (MIP de la Corporación Colombiana de Investigación Agropecuaria (Corpoica, en el Centro de Investigación Tibaitat

  15. Psychrotolerant Endophytic Pseudomonas sp. Strains OB155 and OS261 Induced Chilling Resistance in Tomato Plants (Solanum lycopersicum Mill.) by Activation of Their Antioxidant Capacity.

    Science.gov (United States)

    Subramanian, Parthiban; Mageswari, Anbazhagan; Kim, Kiyoon; Lee, Yi; Sa, Tongmin

    2015-10-01

    Studies on chilling stress damage and its mitigation through microorganisms in members of family Solanaceae is limited, despite their economic importance. We studied chilling stress alleviation in tomato plants colonized by psychrotolerant bacterial strains Pseudomonas vancouverensis OB155-gfp and P. frederiksbergensis OS261-gfp. Log phase cultures of bacterial strains were coated on surface-sterilized seeds (bacterization) before sowing and nonbacterized (control) seeds were coated with sterile bacterial growth medium. All plants were grown at temperatures of 30 and 25°C and at the end of 4 weeks, chilling treatment (12 and 10°C) was imposed for 1 week on half of the bacterized and control plants. Under normal conditions (30 and 25°C), no significant difference was observed in antioxidant activity, proline accumulation, and expression of cold acclimation genes in tomato leaf tissues of both control and bacterized plants. However, plants exposed to temperatures of 12 and 10°C were found to decrease in robustness and nutrient uptake, accompanied by increased membrane damage. Chilling resistance in bacterized plants was evident from reduced membrane damage and reactive oxygen species levels, improved antioxidant activity in leaf tissues, and high expression of cold acclimation genes LeCBF1 and LeCBF3 compared with control plants. Confocal microscopy confirmed effective colonization and intercellular localization of cold-adapted bacterial strains OB155-gfp and OS261-gfp.

  16. Isolation, molecular characterization and growth-promotion activities of a cold tolerant bacterium Pseudomonas sp. NARs9 (MTCC9002) from the Indian Himalayas.

    Science.gov (United States)

    Mishra, Pankaj K; Mishra, Smita; Bisht, Shekhar C; Selvakumar, G; Kundu, S; Bisht, J K; Gupta, Hari Shankar

    2009-01-01

    A bacterium that grows and expresses plant growth promotion traits at 4 degrees C was isolated from the rhizospheric soil of Amaranth, cultivated at a high altitude location in the North Western Indian Himalayas. The isolate was Gram negative and the cells appeared as rods (2.91 x 0.71 microm in size). It grew at temperatures ranging from 4 to 30 degrees C, with a growth optimum at 28 degrees C. It exhibited tolerance to a wide pH range (5-10; optimum 8.0) and salt concentrations up to 6% (wt/vol). Although it was sensitive to Rifampicin (R 20 microg mi-1), Gentamicin (G 3 microg mi-1), and Streptomycin (S 5 microg mi-1), it showed resistance to higher concentrations of Ampicillin (A 500 microg mi-1), Penicillin (P 300 microg mi-1), Polymixin B sulphate (Pb 100 microg mi-1) and Chloramphenicol (C 200 microg mi-1). The 16S rRNA sequence analysis revealed maximum identity with Pseudomonas lurida. The bacterium produced indole Acetic Acid (IAA) and solubilizes phosphate at 4, 15 and 28 degrees C. It also retained its ability to produce rhamnolipids and siderophores at 15 degrees C. Seed bacterization with the isolate enhanced the germination, shoot and root lengths of thirty-day-old wheat seedlings by 19.2, 30.0 & 22.9% respectively, as compared to the un-inoculated controls.

  17. Expression and characterization of thermotolerant lipase with broad pH profiles isolated from an Antarctic Pseudomonas sp strain AMS3

    Science.gov (United States)

    2016-01-01

    A gene encoding a thermotolerant lipase with broad pH was isolated from an Antarctic Pseudomonas strain AMS3. The recombinant lipase AMS3 was purified by single-step purification using affinity chromatography, yielding a purification fold of approximately 1.52 and a recovery of 50%. The molecular weight was approximately ∼60 kDa including the strep and affinity tags. Interestingly, the purified Antarctic AMS3 lipase exhibited broad temperature profile from 10–70 °C and stable over a broad pH range from 5.0 to pH 10.0. Various mono and divalent metal ions increased the activity of the AMS3 lipase, but Ni2+ decreased its activity. The purified lipase exhibited the highest activity in the presence of sunflower oil. In addition, the enzyme activity in 25% v/v solvents at 50 °C particularly to n-hexane, DMSO and methanol could be useful for catalysis reaction in organic solvent and at broad temperature. PMID:27781152

  18. Pseudomonas sp. ZXY-1, a newly isolated and highly efficient atrazine-degrading bacterium, and optimization of biodegradation using response surface methodology.

    Science.gov (United States)

    Zhao, Xinyue; Wang, Li; Ma, Fang; Bai, Shunwen; Yang, Jixian; Qi, Shanshan

    2017-04-01

    Atrazine, a widely used herbicide, is increasing the agricultural production effectively, while also causing great environmental concern. Efficient atrazine-degrading bacterium is necessary to removal atrazine rapidly to keep a safe environment. In the present study, a new atrazine-degrading strain ZXY-1, identified as Pseudomonas, was isolated. This new isolated strain has a strong ability to biodegrade atrazine with a high efficiency of 9.09mg/L/hr. Temperature, pH, inoculum size and initial atrazine concentration were examined to further optimize the degradation of atrazine, and the synthetic effect of these factors were investigated by the response surface methodology. With a high quadratic polynomial mathematical model (R(2)=0.9821) being obtained, the highest biodegradation efficiency of 19.03mg/L/hr was reached compared to previous reports under the optimal conditions (30.71°C, pH7.14, 4.23% (V/V) inoculum size and 157.1mg/L initial atrazine concentration). Overall, this study provided an efficient bacterium and approach that could be potentially useful for the bioremediation of wastewater containing atrazine. Copyright © 2016. Published by Elsevier B.V.

  19. Phenazine-1-carboxamide (PCN) from Pseudomonas sp. strain PUP6 selectively induced apoptosis in lung (A549) and breast (MDA MB-231) cancer cells by inhibition of antiapoptotic Bcl-2 family proteins.

    Science.gov (United States)

    Kennedy, R Kamaraj; Veena, V; Naik, P Ravindra; Lakshmi, Pragna; Krishna, R; Sudharani, S; Sakthivel, N

    2015-06-01

    Phenazine-1-carboxamide (PCN), a naturally occurring simple phenazine derivative isolated from Pseudomonas sp. strain PUP6, exhibited selective cytotoxic activity against lung (A549) and breast (MDA-MB-231) cancer cell lines in differential and dose-dependent manner compared to normal peripheral blood mononuclear cells. PCN-treated cancer cells showed the induction of apoptosis as evidenced by the release of low level of LDH, morphological characteristics, production of reactive oxygen species, loss of mitochondrial membrane potential (ΔΨm) and induction of caspase-3. At molecular level, PCN instigates apoptosis by mitochondrial intrinsic apoptotic pathway via the overexpression of p53, Bax, cytochrome C release and activation of caspase-3 with the inhibition of oncogenic anti-apoptotic proteins such as PARP and Bcl-2 family proteins (Bcl-2, Bcl-w and Bcl-xL). The in silico docking studies of PCN targeted against the anti-apoptotic members of Bcl-2 family proteins revealed the interaction of PCN with the BH3 domain, which might lead to the induction of apoptosis due to the inhibition of antiapoptotic proteins. Due to its innate inhibition potential of antiapoptotic Bcl-2 family proteins, PCN may be used as potent anticancer agent against both lung and breast cancer.

  20. Las-like quorum-sensing system negatively regulates both pyoluteorin and phenazine-1-carboxylic acid production in Pseudomonas sp. M18

    Institute of Scientific and Technical Information of China (English)

    CHEN Yun; WANG XiaoLei; HUANG XianQing; ZHANG XueHong; XU YuQuan

    2008-01-01

    A las-like quorum-sensing system in Pseudornonas sp. M18 was identified, which consisted of lasl and lasR genes encoding LuxI-LuxR type regulator. Several functions of the las system from strain M18 were investigated in this study. The chromosomal inactivation of either lasl or lasR by recombination increased the production of both pyoluteorin (Pit) and phenazine-1-carboxylic acid (PCA) by 4-5 fold and 2-3 fold over that of the wild type atrein of M18, respectively. Production of both antibiotics was restored to wild-type levels after in trans complementation with the wild-type lasl or lasR gene. Expression of the translational fusions pltA'-'lacZand phzA'-'lacZfurther confirmed the negative effect of lasl or lasR on both biosynthetic operons, and it was also demonstrated that the las system was related to the ability of swarming motility and the inhibition of cell growth.

  1. Alterações metabólicas em plantas de feijão originadas de sementes microbiolizadas por Pseudomonas sp. e inoculadas com Xanthomonas axonopodis pv. phaseoli Metabolic alterations on bean plants originated from microbiolization of seeds with Pseudomonas sp. and inoculated with Xanthomnas axonopodis pv. phaseoli

    Directory of Open Access Journals (Sweden)

    Eliane Gonçalves da Silva

    2009-06-01

    Full Text Available Muitas enzimas estão envolvidas em reações de defesa de plantas contra patógenos. O objetivo deste trabalho foi verificar alterações na atividade de algumas destas enzimas em plantas de feijão originadas de sementes microbiolizadas com um isolado de Pseudomonas do grupo das fluorescentes (isolado DFs842. Sementes de feijão cultivar BRS Valente foram imersas em suspensão salina preparada a partir de crescimento bacteriano com 24 h do isolado de Pseudomonas (OD540=0,5 sabidamente biocontroladora de Xanthomonas axonopodis pv. phaseoli. Como testemunhas, as sementes foram imersas em solução salina (NaCl 0,85%. Após a microbiolização por 5 h a 10ºC, as sementes foram plantadas em vasos contendo uma mistura de solo não esterilizado, areia e esterco bovino (proporção 3:1:1, mantidos em casa de vegetação. A inoculação do patógeno foi realizada na terceira folha verdadeira de todas as plantas, fazendo-se cortes com tesoura imersa em suspensão salina do patógeno (X. axonopodis pv. phaseoli preparada a partir de crescimento de 24 h (OD540=0,4. Câmaras úmidas foram mantidas 24 h antes e após a inoculação. Para o preparo do extrato protéico, as três primeiras folhas verdadeiras foram coletadas individualmente em 5 épocas de coleta distintas: uma, momentos antes da inoculação e as demais nos tempos seis, 24, 72 h e 15 dias após a inoculação. Este extrato protéico serviu de fonte para as determinações do teor de proteínas solúveis totais (PST, atividade da polifenol oxidase (PPO e da peroxidase (PO, as quais foram realizadas por leituras espectrofotométricas. Os resultados demonstraram aumento significativo no teor de PST e na atividade de PPO nas plantas submetidas ao tratamento com isolado DFs842, sendo que, o teor de PST foi o dobro, em relação às plantas não tratadas. Também foi observado que, mesmo antes da inoculação do patógeno o teor de PST e a atividade de PPO nas plantas tratadas estavam bem maiores

  2. Simply enhancing throughput of free-flow electrophoresis via organic-aqueous environment for purification of weak polarity solute of phenazine-1-carboxylic acid in fermentation of Pseudomonas sp. M18.

    Science.gov (United States)

    Yang, Jing-Hua; Shao, Jing; Wang, Hou-Yu; Dong, Jing-Yu; Fan, Liu-Yin; Cao, Cheng-Xi; Xu, Yu-Quan

    2012-09-01

    Herein, a simple novel free-flow electrophoresis (FFE) method was developed via introduction of organic solvent into the electrolyte system, increasing the solute solubility and throughput of the sample. As a proof of concept, phenazine-1-carboxylic acid (PCA) from Pseudomonas sp. M18 was selected as a model solute for the demonstration on feasibility of novel FFE method on account of its faint solubility in aqueous circumstance. In the developed method, the organic solvent was added into not only the sample buffer to improve the solubility of the solute, but also the background buffer to construct a uniform aqueous-organic circumstance. These factors of organic solvent percentage and types as well as pH value of background buffer were investigated for the purification of PCA in the FFE device via CE. The experiments revealed that the percentage and the types of organic solvent exerted major influence on the purification of PCA. Under the optimized conditions (30 mM phosphate buffer in 60:40 (v/v) water-methanol at an apparent pH 7.0, 3.26 mL/min background flux, 10-min residence time of injected sample, and 400 V), PCA could be continuously purified from its impurities. The flux of sample injection was 10.05 μL/min, and the recovery was up to 93.7%. An 11.9-fold improvement of throughput was found with a carrier buffer containing 40% (v/v) methanol, compared with the pure aqueous phase. The developed procedure is of evident significance for the purification of weak polarity solute via FFE.

  3. 深海细菌 Pseudomonas sp.bIp-2黑色素生成条件研究及其 hppD基因的克隆%Studies on the melanin production and gene cloning of hppD from the deep-sea bacterium Pseudomonas sp.bIp-2

    Institute of Scientific and Technical Information of China (English)

    韦海镧; 于丽波; 易志伟; 汤熙翔

    2014-01-01

    A melanin-producing strain was isolated from deep-sea sediment of the Atlantic Ocean and identified as Pseudomonas sp.bIp-2 by 16S rRNA gene sequencing.The study of growth and melanin production with varied culture conditions show that the melanin production in strain bIp-2 is growth-associated.The maximum yield of pig-ment was obtained after the culture attained the stationary growth phase.The temperature range for growth is 4~37℃ with optimal growth at 37℃,and the maximum melanin production was observed at 28℃.The pH range for growth is 6.0~9.0,with both optimal growth and melanin formation both being at pH 7.0.Strain bIp-2 grew in 1%~9%NaCl with a maximum melanin production at 5%NaCl.Low concentration of Fe(II)(0.05 mmol/dm3 ) can improve the production of melanin.Fe2+of more than 0.20 mmol/dm3 suppressed the melanin production and Fe2+of more than 1 .00 mmol/dm3 completely inhibited the growth of the strain.Cu2+of 0.1 mmol/dm3 had no effect to the melanin production and Cu2+of more than 0.5 mmol/dm3 inhibited the formation of melanin.Cu2+over 1 .0 mmol/dm3 completely inhibited the growth of the strain.A 1 087 bp fragment of the full-length hppD gene was amplified from the strain bIp-2.The hppD gene encoded an amino acid sequence sharing a 97%similarity with the HPPD from Pseudomonas stutzeri RCH2.These results laid a foundation to the study of the synthesis,applica-tion and ecological effect of the melanin from Pseudomonas sp.bIp-2.%从大西洋深海沉积物中分离得到1株产黑色素细菌bIp-2,16S rRNA基因序列分析表明该菌隶属于假单胞菌属(Pseudomonas),与施氏假单胞菌(P.stutzeri)有最高的16S rRNA基因序列相似性(99%).进一步对该菌的生长及产黑色素条件进行了初步研究,结果表明bIp-2在稳定生长期后期才开始大量积累黑色素;bIp-2可在4~37℃的温度范围下生长,最适生长温度为37℃,在28℃具有最高的黑色素产量;bIp-2生长的p

  4. Degradation of aromatics and chloroaromatics by Pseudomonas sp. strain B13: purification and characterization of 3-oxoadipate:succinyl-coenzyme A (CoA) transferase and 3-oxoadipyl-CoA thiolase.

    Science.gov (United States)

    Kaschabek, Stefan R; Kuhn, Bernd; Müller, Dagmar; Schmidt, Eberhard; Reineke, Walter

    2002-01-01

    The degradation of 3-oxoadipate in Pseudomonas sp. strain B13 was investigated and was shown to proceed through 3-oxoadipyl-coenzyme A (CoA) to give acetyl-CoA and succinyl-CoA. 3-Oxoadipate:succinyl-CoA transferase of strain B13 was purified by heat treatment and chromatography on phenyl-Sepharose, Mono-Q, and Superose 6 gels. Estimation of the native molecular mass gave a value of 115,000 +/- 5,000 Da with a Superose 12 column. Polyacrylamide gel electrophoresis under denaturing conditions resulted in two distinct bands of equal intensities. The subunit A and B values were 32,900 and 27,000 Da. Therefore it can be assumed that the enzyme is a heterotetramer of the type A2B2 with a molecular mass of 120,000 Da. The N-terminal amino acid sequences of both subunits are as follows: subunit A, AELLTLREAVERFVNDGTVALEGFTHLIPT; subunit B, SAYSTNEMMTVAAARRLKNGAVVFV. The pH optimum was 8.4. Km values were 0.4 and 0.2 mM for 3-oxoadipate and succinyl-CoA, respectively. Reversibility of the reaction with succinate was shown. The transferase of strain B13 failed to convert 2-chloro- and 2-methyl-3-oxoadipate. Some activity was observed with 4-methyl-3-oxoadipate. Even 2-oxoadipate and 3-oxoglutarate were shown to function as poor substrates of the transferase. 3-oxoadipyl-CoA thiolase was purified by chromatography on DEAE-Sepharose, blue 3GA, and reactive brown-agarose. Estimation of the native molecular mass gave 162,000 +/- 5,000 Da with a Superose 6 column. The molecular mass of the subunit of the denatured protein, as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, was 42 kDa. On the basis of these results, 3-oxoadipyl-CoA thiolase should be a tetramer of the type A4. The N-terminal amino acid sequence of 3-oxoadipyl-CoA thiolase was determined to be SREVYI-DAVRTPIGRFG. The pH optimum was 7.8. Km values were 0.15 and 0.01 mM for 3-oxoadipyl-CoA and CoA, respectively. Sequence analysis of the thiolase terminus revealed high percentages of identity

  5. Characterization and proteomic analysis of the Pseudomonas sp. HK-6 xenB knockout mutant under RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) stress.

    Science.gov (United States)

    Lee, Bheong-Uk; Choi, Moon-Seop; Oh, Kye-Heon

    2015-01-01

    Pseudomonas sp. HK-6 is able to utilize RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) as its sole nitrogen source. The role of the xenB gene, encoding xenobiotic reductase B, was investigated using HK-6 xenB knockout mutants. The xenB mutant degraded RDX to a level that was 10-fold less than that obtained with the wild-type HK-6 strain. After 60 days of culture with 25 or 50 μM RDX, no residual RDX was detected in the supernatants of the wild-type aerobically grown cultures, whereas approximately 90 % of the RDX remained in the xenB mutant cultures. The xenB mutant bacteria exhibited a 10(2)-10(4)-fold decrease in survival rate compared to the wild-type. The expression of DnaK and GroEL proteins, two typical stress shock proteins (SSPs), in the xenB mutant increased after immediate exposure to RDX, yet dramatically decreased after 4 h of exposure. In addition, DnaK and GroEL were more highly expressed in the cultures with 25 μM RDX in the medium but showed low expression in the cultures with 50 or 75 μM RDX. The expression levels of the dnaK and groEL genes measured by RT-qPCR were also much lower in the xenB genetic background. Analyses of the proteomes of the HK-6 and xenB mutant cells grown under conditions of RDX stress showed increased induction of several proteins, such as Alg8, alginate biosynthesis sensor histidine kinase, and OprH in the xenB mutants when compared to wild-type. However, many proteins, including two SSPs (DnaK and GroEL) and proteins involved in metabolism, exhibited lower expression levels in the xenB mutant than in the wild-type HK-6 strain. The xenB knockout mutation leads to reduced RDX degradation ability, which renders the mutant more sensitive to RDX stress and results in a lower survival rate and an altered proteomic profile under RDX stress.

  6. Enzymatic synthesis oF L-tryptophan from D,L-2-amino-delta2-thiazoline-4-carboxylic acid and indole by Pseudomonas sp. TS1138 L-2-amino-delta2-thiazoline-4-carboxylic acid hydrolase, S-carbamyl-L-cysteine amidohydrolase, and Escherichia coli L-tryptophanase.

    Science.gov (United States)

    Du, J; Duan, J J; Zhang, Q; Hou, J; Bai, F; Chen, N; Bai, G

    2012-01-01

    L-Tryptophan (L-Trp) is an essential amino acid. It is widely used in medical, health and food products, so a low-cost supply is needed. There are 4 methods for L-Trp production: chemical synthesis, extraction, enzymatic synthesis, and fermentation. In this study, we produced a recombinant bacterial strain pET-tnaA of Escherichia coli which has the L-tryptophanase gene. Using the pET-tnaA E. coli and the strain TS1138 of Pseudomonas sp., a one-pot enzymatic synthesis of L-Trp was developed. Pseudomonas sp. TS1138 was added to a solution of D,L-2-amino-delta2-thiazoline-4-carboxylic acid (DL-ATC) to convert it to L-cysteine (L-Cys). After concentration, E. coli BL21 (DE 3) cells including plasmid pET-tnaA, indole, and pyridoxal 5'-phosphate were added. At the optimum conditions, the conversion rates of DL-ATC and L-Cys were 95.4% and 92.1%, respectively. After purifying using macroporous resin S8 and NKA-II, 10.32 g of L-Trp of 98.3% purity was obtained. This study established methods for one-pot enzymatic synthesis and separation of L-Trp. This method of producing L-Trp is more environmentally sound than methods using chemical synthesis, and it lays the foundations for industrial production of L-Trp from DL-ATC and indole.

  7. Insights into the mechanisms of Promysalin, a secondary metabolite with genus-specific antibacterial activity against Pseudomonas

    Science.gov (United States)

    Promysalin, a secondary metabolite produced by Pseudomonas putida RW10S1, has antibacterial activity against a wide variety of Pseudomonas sp., including both human and plant pathogens. Promysalin induces swarming and biofilm formation in the producing species, and inhibits growth of susceptible sp...

  8. Nitrogen and Phosphorus Removal Characteristics and Kinetics of Pseudomonas sp.Strain P1-1%假单胞菌P1-1脱氮除磷特性及其动力学研究

    Institute of Scientific and Technical Information of China (English)

    洪武林; 谢学辉; 于文娟; 张武刚; 柳建设

    2012-01-01

    Pseudomonas sp. Strain Pl-1 which was screened in laboratory was studied for its nitrogen and phosphorus removal characteristics. Effects of temperature, pH, bacteria amount, shaking speed and carbon source on growth as well as nitrogen and phosphorus removal of the strain were discussed. Kinetics of the strain in the phosphorus removal was also studied. Results indic ated that the optimum conditions for the growth of the strain were shaking speed at 140 r/min, inoculation 10%, pH 8.0 and temperature at 30 ℃, while the optimum conditions for phosphorus removal by the strain were shaking speed at 140 r/min, inoculation 10%, temperature at 30℃ and pH 8.0, and the optimum conditions for nitrogen removal by the strain were inoculation 10%, shaking speed at 0 r/min, temperature at 30 ℃ and pH 7.0. The lowest concentration of sodium acetate for the good growth and nitration and phosphorus removal of the strain was 1 000 mg/L. The kinetics of phosphorus removal between 6 mg/L and 21 mg/L were preliminary studied with the Monod model zero-order reaction.%利用实验室中筛选到的假单胞菌P1-1菌株进行脱氮除磷研究,并探讨了温度、pH、接种量、摇床转速和碳源对该菌株生长和脱氮除磷的影响,同时研究了菌株除磷的动力学.结果表明,该菌株最佳生长条件为摇床转速l40 r/min、接种量10%、pH 8.0、温度30℃,最佳除磷条件为摇床转速140 r/min、接种量10%、温度30℃、pH 8.0,最佳脱氮条件为接种量10%、摇床转速0、温度30℃、pH 7.0;该菌株在比较好的生长和脱氮除磷效果时需要乙酸钠的最低浓度为1 000 mg/L;当初始P浓度为6~21 mg/L时,菌株除磷的动力学过程符合Monod零级反应模型.

  9. Management and treatment of contact lens-related Pseudomonas keratitis

    Directory of Open Access Journals (Sweden)

    Willcox MD

    2012-06-01

    Full Text Available Mark DP WillcoxSchool of Optometry and Vision Science, University of New South Wales, Sydney, AustraliaAbstract: Pubmed and Medline were searched for articles referring to Pseudomonas keratitis between the years 2007 and 2012 to obtain an overview of the current state of this disease. Keyword searches used the terms "Pseudomonas" + "Keratitis" limit to "2007–2012", and ["Ulcerative" or "Microbial"] + "Keratitis" + "Contact lenses" limit to "2007–2012". These articles were then reviewed for information on the percentage of microbial keratitis cases associated with contact lens wear, the frequency of Pseudomonas sp. as a causative agent of microbial keratitis around the world, the most common therapies to treat Pseudomonas keratitis, and the sensitivity of isolates of Pseudomonas to commonly prescribed antibiotics. The percentage of microbial keratitis associated with contact lens wear ranged from 0% in a study from Nepal to 54.5% from Japan. These differences may be due in part to different frequencies of contact lens wear. The frequency of Pseudomonas sp. as a causative agent of keratitis ranged from 1% in Japan to over 50% in studies from India, Malaysia, and Thailand. The most commonly reported agents used to treat Pseudomonas keratitis were either aminoglycoside (usually gentamicin fortified with a cephalosporin, or monotherapy with a fluoroquinolone (usually ciprofloxacin. In most geographical areas, most strains of Pseudomonas sp. (≥95% were sensitive to ciprofloxacin, but reports from India, Nigeria, and Thailand reported sensitivity to this antibiotic and similar fluoroquinolones of between 76% and 90%.Keywords: Pseudomonas, keratitis, contact lens

  10. Regulation of the biosynthesis of cyclic lipopeptides from Pseudomonas putida PCL1445

    NARCIS (Netherlands)

    Dubern, Jean-Frédéric

    2006-01-01

    Pseudomonas putida strain PCL1445 produces two cyclic lipopeptides, named putisolvins I and II, which represent a Novel class of biosurfactants. Putisolvins reduce the surface tension between liquid and air, and disrupt already existing biofilms of several Pseudomonas sp., including those of the

  11. Regulation of the biosynthesis of cyclic lipopeptides from Pseudomonas putida PCL1445

    NARCIS (Netherlands)

    Dubern, Jean-Frédéric

    2006-01-01

    Pseudomonas putida strain PCL1445 produces two cyclic lipopeptides, named putisolvins I and II, which represent a Novel class of biosurfactants. Putisolvins reduce the surface tension between liquid and air, and disrupt already existing biofilms of several Pseudomonas sp., including those of the opp

  12. Pseudomonas aeruginosa in Healthcare Settings

    Science.gov (United States)

    ... Address What's this? Submit What's this? Submit Button Pseudomonas aeruginosa in Healthcare Settings Recommend on Facebook Tweet ... and/or help treat infections? What is a Pseudomonas infection? Pseudomonas infection is caused by strains of ...

  13. Isolation and evaluation of potent Pseudomonas species for bioremediation of phorate in amended soil.

    Science.gov (United States)

    Jariyal, Monu; Gupta, V K; Jindal, Vikas; Mandal, Kousik

    2015-12-01

    Use of phorate as a broad spectrum pesticide in agricultural crops is finding disfavor due to persistence of both the principal compound as well as its toxic residues in soil. Three phorate utilizing bacterial species (Pseudomonas sp. strain Imbl 4.3, Pseudomonas sp. strain Imbl 5.1, Pseudomonas sp. strain Imbl 5.2) were isolated from field soils. Comparative phorate degradation analysis of these species in liquid cultures identified Pseudomonas sp. strain Imbl 5.1 to cause complete metabolization of phorate during seven days as compared to the other two species in 13 days. In soils amended with phorate at different levels (100, 200, 300 mg kg(-1) soil), Pseudomonas sp. strain Imbl 5.1 resulted in active metabolization of phorate by between 94.66% and 95.62% establishing the same to be a potent bacterium for significantly relieving soil from phorate residues. Metabolization of phorate to these phorate residues did not follow the first order kinetics. This study proves that Pseudomonas sp. strain Imbl 5.1 has huge potential for active bioremediation of phorate both in liquid cultures and agricultural soils.

  14. Hydrolytic potential of a psychrotrophic Pseudomonas isolated from refrigerated raw milk

    Directory of Open Access Journals (Sweden)

    Ana Paula F. Corrêa

    2011-12-01

    Full Text Available The production of extracellular hydrolases by a psychrotrophic bacterium isolated from refrigerated raw milk, and identified as a Pseudomonas sp. belonging to the Pseudomonas jenssenii group, was studied. This bacterium produced proteolytic and lipolytic enzymes in all media investigated (skim milk, cheese whey, casein broth, and tryptone soy broth. High levels of α-glucosidase were produced in skim milk broth. Hydrolytic enzymes detected in skim milk broth are of particular concern, indicating that these enzymes could be produced by Pseudomonas sp. during the cold storage of raw milk, contributing to the spoilage problem in milk and dairy products.

  15. Pseudomonas screening assay

    Science.gov (United States)

    Margalit, Ruth (Inventor)

    1993-01-01

    A method for the detection of Pseudomonas bacteria is described where an Azurin-specific antibody is employed for detecting the presence of Azurin in a test sample. The detection of the presence of Azurin in the sample is a conclusive indicator of the presence of the Pseudomonas bacteria since the Azurin protein is a specific marker for this bacterial strain.

  16. Meroterpenes from Penicillium sp found in association with Melia azedarach.

    Science.gov (United States)

    Geris dos Santos, Regina M; Rodrigues-Fo, Edson

    2002-12-01

    A Penicillium sp was isolated from the root bark of Melia azedarach and cultivated over sterilized rice. After chromatographic procedures, two meroterpenes, named preaustinoid A and B, were obtained in addition to the known alkaloid verruculogen. Their structures were identified by extensive spectroscopic studies, and they exhibited moderate bacteriostatic effects on Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Bacillus sp.

  17. Monocyte Profiles in Critically Ill Patients With Pseudomonas Aeruginosa Sepsis

    Science.gov (United States)

    2017-02-02

    Pseudomonas Infections; Pseudomonas Septicemia; Pseudomonas; Pneumonia; Pseudomonal Bacteraemia; Pseudomonas Urinary Tract Infection; Pseudomonas Gastrointestinal Tract Infection; Sepsis; Sepsis, Severe; Critically Ill

  18. On the Optimization of Growth Conditions of Pseudomonas sp. YT3 and Bacillus subtilis DZ1 in Fermentation Cylinders%假单胞菌YT3和枯草芽孢杆菌DZ1的发酵罐生长条件优化

    Institute of Scientific and Technical Information of China (English)

    马海林; 井大炜; 王爱杰; 丁延芹; 刘方春; 杜振宇; 马丙尧

    2013-01-01

    假单胞菌(Pseudomonas sp.)YT3和枯草芽孢杆菌(Bacillus subtilis)DZ1是从植物根际土壤筛选出的具有应用潜力的植物根际促生细菌。研究发酵罐中接种量、转速、通气量等因素对 YT3菌量以及对 DZ1芽孢率、菌量的影响。结果表明:不同的接种量、转速和通气量对Pseudomonas sp. YT3的活菌数、Bacillus subtilis DZ1的活菌数及芽孢率均有显著影响。10%的接种量、2 m3/h的通气量对YT3和DZ1菌株的作用效果与15%的接种量、3 m3/h相当,但显著高于5%的接种量和1 m3/h。当转速为200 r/min时,YT3具有最高的活菌数,DZ1具有最高的活菌数和芽孢率。综合分析认为,YT3和DZ1发酵罐的最佳条件为接种量10%、转速200 r/min和通气量2 m3/h。%Pseudomonas sp. YT3 and Bacillus subtilis DZ1, isolated and screened from the plant rhizo-sphere soil, were plant growth-promoting rhizo-bacteria exhibiting broad application prospects in the bio-fertilizer production. Taking YT3 and DZ1 bacterial strains as research objects, the experiment were conducted to study the influence of inoculation quantity, rotating speed and minute ventilation on the bacteria population and spore rates of YT3 and DZ1 in the fermentation cylinders. The results indicated that different inoculation quantity, rotating speed and minute ventilation could have significantly effects on the bacteria population and spore rates of YT3 and DZ1. Effects of the 10%inoculation quantity and 2 m3/h ventilation were similar on the bacteria population and spore rates of YT3 and DZ1 with that of the 15% inoculation quantity and 3 m3/h ventilation, however, their effects were higher than that of the 5%inoculation quantity and 2 m3/h ventilation. The numbers of YT3, as well as the numbers and the spore rates of DZ1 reached the highest under 200r/min rotating speed. As a result, the optimum fermentation cylinder conditions of YT3 and DZ1 were 10% inoculation quantity, 200 r

  19. 40 CFR 180.1114 - Pseudomonas fluorescens A506, Pseudomonas fluorescens 1629RS, and Pseudomonas syringae 742RS...

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Pseudomonas fluorescens A506, Pseudomonas fluorescens 1629RS, and Pseudomonas syringae 742RS; exemptions from the requirement of a tolerance... Tolerances § 180.1114 Pseudomonas fluorescens A506, Pseudomonas fluorescens 1629RS, and Pseudomonas...

  20. Regulation of GacA on two phz gene clusters and quorum sensing in Pseudomonas sp.M18%GacA对假单胞菌株M18两个phz基因簇和菌群传感的调控

    Institute of Scientific and Technical Information of China (English)

    史鸣奇; 李雅乾; 王沂; 黄娇芳; 黄显清; 许煜泉

    2009-01-01

    [目的]假单胞菌株M18(Pseudomonas sp.M18)是从甜瓜根际土壤中分离获得的一株对多种植物病原菌具有显著拮抗作用的菌株,在菌群传感(quorum sensing)系统的调控下,能分泌吩嗪-1-羧酸(PCA)以及多种吩嗪(phz)类衍生物的抗真菌物质.全局性因子GacA是M18菌株吩嗪类物质的合成与菌群传感系统的重要调控因子,本文将就GacA对上述两者的调控做进一步研究.[方法]PCR基因扩增和测序研究M18菌株中PCA合成基因簇,运用RT-PCR及构建phzA-lacZ转录融合手段研究M18菌株中两个phz二基因簇各自的转录特征以及受全局性因子GacA的调控作用,运用翻译融合手段进一步研究M18菌株中GacA对菌群传感系统的调控作用.[结果]M18菌株的染色体中存在着两个PCA合成基因簇phz-G1和phzA2-G2,与铜绿假单胞菌株(P.aeruginosa)PAO1的一致性达99%.但是,M18菌株phzA2-G2基因簇下游的非编码区与PAO1菌株不同,存在着三段单位长度为144 bp的重复序列;在野生菌株M18中,phzA1-G1的转录水平明显高于phzA2-G2,GacA促进phzA1-G1转录,抑制phzA2-G2转录,区别性地调控两个phz二基因簇的转录,GacA在整体上抑制phz基因簇的转录,与PAO1菌株中,GacA对phz的调控方式相反;gacA基因突变对菌群传感系统中lux家族基因中的lasI表达量无显著影响,但正调控las系统下游的而rhll表达量,GacA对phz基因簇表达的调控部分通过菌群传感系统实现.[结论]在M18菌株和PAO1菌株中,GacA对吩嗪类产物合成的调控方式相反,对菌群传感系统的调控也存在着差异性,这些差异可能是两个菌株在各自不同生境下长期进化的结果.%[Objective] The regulatory function investigation of two component system gacS/gacA on two phz gene clusters expression and quorum sensing system (QS) in Pseudomonas . sp. M18. [Methods] The two phz gene clusters were sequenced and the expressional features by GacA were analyzed using RT

  1. CHARACTERIZATION OF PHYTOPATHOGENIC FUNGI, BACTERIA, NEMATODES AND VIRUSES IN FOUR COMMERCIAL VARIETIES OF HELICONIA (Heliconia sp. CARACTERIZACIÓN DE HONGOS, BACTERIAS, NEMÁTODOS Y VIRUS FITOPATÓGENOS EN CUATRO VARIEDADES COMERCIALES DE HELICONIA (Heliconia sp.

    Directory of Open Access Journals (Sweden)

    Nathali López Cardona

    2012-06-01

    Full Text Available Abstract. Analysis of 914 samples of roots, rhizomes, pseudostems, inflorescences and leaves of four commercial varieties of heliconia, cultivated at the municipality of Chinchiná-Caldas (Colombia, allowed to identify five genera of plant pathogenic fungi (Rhizoctonia, Fusarium, Colletotrichum, Helminthosporium and Curvularia, three genera of plant pathogenic bacteria (Ralstonia, Pseudomonas and Erwinia, two species of viruses (Banana streak virus (BSV, Badnavirus, and Cucumber mosaic virus (CMV, Cucumovirus,, and seven genera of plant parasitic nematodes (Helicotylenchus, Tylenchus, Meloidogyne, Ditylenchus, Aphelenchoides, Pratylenchus, and Radopholus. Of these, Fusarium sp., affecting pseudostems, Pseudomonas sp., affecting leaves and inflorescences, and the plant parasitic nematodes Ditylenchus sp., Aphelenchoides sp., Pratylenchus sp. and Radopholus sp., are new records in the heliconia production in Colombia . The most limiting diseases corresponded to leaf blight, caused by Helminthosporium sp.; the bacterioses, caused by Pseudomonas sp.; the spotted stems, caused by Fusarium sp.; and soft rot of the pseudostems, caused by Erwinia sp. The pathogenicity tests demonstrated that Colletotrichum sp. and Phoma sp. are not pathogenic in leaves; while Fusarium sp., inoculated in pseudostems, Helminthosporium sp. and Pseudomonas sp., inoculated in leaves, and Colletotrichum sp. and Pseudomonas sp., inoculated in inflorescences, had incidence values of 83.3, 86.6, 93.3, 100.0 and 100.0%, respectively.Resumen. El análisis de 914 muestras de raíces, rizomas, pseudotallos, inflorescencias y hojas de cuatro variedades comerciales de heliconia, cultivadas en el municipio de Chinchiná-Caldas (Colombia, permitieron identificar cinco géneros de hongos fitopatógenos (Rhizoctonia, Fusarium, Colletotrichum, Helminthosporium y Curvularia, tres géneros de bacterias fitopatógenas (Ralstonia, Pseudomonas y Erwinia, dos especies de virus (Banana streak

  2. 一株假单胞菌的亚硝酸盐降解特性及其对鱼池底泥的净化作用%Nitrite degradation of a Pseudomonas sp. strain SF1 and its applicaiton in fish pond sediment

    Institute of Scientific and Technical Information of China (English)

    陈瑞芳; 徐长安; 刘丽梅; 方卫东

    2011-01-01

    从海水养殖池的底泥中筛选到一株对亚硝酸盐有强降解作用的假单胞菌(Pseudomonas sp.)SF1,在实验室条件下研究了SF1的亚硝酸盐降解特性及其对高污染鱼池底泥的净化作用。研究结果表明,SF1具有高效降解转化高浓度亚硝酸钠的能力,其适宜降解条件为:亚硝酸钠质量浓度范围为1~1000mg/L;菌种接种量为10%;中量充气发酵;发酵时间为12~36h;发酵pH值为6.5~8.0。直接接种SF1发酵液(接种量10%,菌液A值0.36)到鱼池底泥,36h后,底泥的亚硝酸盐去除率达到67%,显示了SF1对鱼%A strain of Pseudomonas sp., named as SF1, which showed high capacity of nitrite degradation, was screened from the mud of marine culturing pond. SF1 nitrite-degrading property and its application in fish pond sediment were carried out under lab environment. SF1 showed a high ability to degrade sodium nitrite at the following conditions, 1-1000 mg/L of sodium nitrite concentrate, 10% of denitrifying bacteria inoculums, median aerating during fermentation; pH ranging between 6.5-8.0, and 12-36 h of fermentation time. Introducing SF1 fermentation broth (A value 0.36) into fish pond sediment at the ratio of 10% removed 67% of nitrite after 36 h. Our results indicate that SF1 can be used to treat fish pond sediment.

  3. An unknown trees die back caused by Pseudomonas species in Switzerland

    OpenAIRE

    Lefort, François; Crovadore, Julien; Gilodi, Romain; Calmin, Gautier; Oszako, Tomasz; Nowakowska, Justyna A.

    2009-01-01

    A model for tree pathogen diagnosis – Prunus domestica L. has been studied against pathogenic bacteria. An orchard of 110 trees of P. domestica showed dying back symptoms in May 2009 and nineteen of these trees were eradicated and burnt for prophylaxis. No symptoms correlated with those caused by pathogens previously observed in stone fruit die back in Europe or elsewhere (Pseudomonas syringae pv syringae van Hall, Pseudomonas syringae pv morsprunorum Lazarowtz, Phytophthora sp., Diaporthe p...

  4. The effect of phylogenetically different bacteria on the fitness of Pseudomonas fluorescens in sand microcosms.

    Directory of Open Access Journals (Sweden)

    Olaf Tyc

    Full Text Available In most environments many microorganisms live in close vicinity and can interact in various ways. Recent studies suggest that bacteria are able to sense and respond to the presence of neighbouring bacteria in the environment and alter their response accordingly. This ability might be an important strategy in complex habitats such as soils, with great implications for shaping the microbial community structure. Here, we used a sand microcosm approach to investigate how Pseudomonas fluorescens Pf0-1 responds to the presence of monocultures or mixtures of two phylogenetically different bacteria, a Gram-negative (Pedobacter sp. V48 and a Gram-positive (Bacillus sp. V102 under two nutrient conditions. Results revealed that under both nutrient poor and nutrient rich conditions confrontation with the Gram-positive Bacillus sp. V102 strain led to significant lower cell numbers of Pseudomonas fluorescens Pf0-1, whereas confrontation with the Gram-negative Pedobacter sp. V48 strain did not affect the growth of Pseudomonas fluorescens Pf0-1. However, when Pseudomonas fluorescens Pf0-1 was confronted with the mixture of both strains, no significant effect on the growth of Pseudomonas fluorescens Pf0-1 was observed. Quantitative real-time PCR data showed up-regulation of genes involved in the production of a broad-spectrum antibiotic in Pseudomonas fluorescens Pf0-1 when confronted with Pedobacter sp. V48, but not in the presence of Bacillus sp. V102. The results provide evidence that the performance of bacteria in soil depends strongly on the identity of neighbouring bacteria and that inter-specific interactions are an important factor in determining microbial community structure.

  5. The effect of phylogenetically different bacteria on the fitness of Pseudomonas fluorescens in sand microcosms.

    Science.gov (United States)

    Tyc, Olaf; Wolf, Alexandra B; Garbeva, Paolina

    2015-01-01

    In most environments many microorganisms live in close vicinity and can interact in various ways. Recent studies suggest that bacteria are able to sense and respond to the presence of neighbouring bacteria in the environment and alter their response accordingly. This ability might be an important strategy in complex habitats such as soils, with great implications for shaping the microbial community structure. Here, we used a sand microcosm approach to investigate how Pseudomonas fluorescens Pf0-1 responds to the presence of monocultures or mixtures of two phylogenetically different bacteria, a Gram-negative (Pedobacter sp. V48) and a Gram-positive (Bacillus sp. V102) under two nutrient conditions. Results revealed that under both nutrient poor and nutrient rich conditions confrontation with the Gram-positive Bacillus sp. V102 strain led to significant lower cell numbers of Pseudomonas fluorescens Pf0-1, whereas confrontation with the Gram-negative Pedobacter sp. V48 strain did not affect the growth of Pseudomonas fluorescens Pf0-1. However, when Pseudomonas fluorescens Pf0-1 was confronted with the mixture of both strains, no significant effect on the growth of Pseudomonas fluorescens Pf0-1 was observed. Quantitative real-time PCR data showed up-regulation of genes involved in the production of a broad-spectrum antibiotic in Pseudomonas fluorescens Pf0-1 when confronted with Pedobacter sp. V48, but not in the presence of Bacillus sp. V102. The results provide evidence that the performance of bacteria in soil depends strongly on the identity of neighbouring bacteria and that inter-specific interactions are an important factor in determining microbial community structure.

  6. Inflammatory reaction and alterations of pulmonary surfactant in Pseudomonas Aeruginosa pneumonia in immunocompromised rats

    Institute of Scientific and Technical Information of China (English)

    瞿介明; 李倬哲; 何礼贤; 孙波; 陈雪华

    2002-01-01

    Pulmonary surfactant (PS) compromises lipids and surfactant proteins (SP) and lines on the alveolar air-liquid interface. It can reduce surface tension, prevent alveoli from collapse and reduce alveoli edema by disaturated dipalmitoylphosphatidylcholine.1 It also modulates the pulmonary immunology by SP-A and SP-D.2 In this study, we established a rat model of immunocompromised host (ICH) with pulmonary infection of Pseudomonas aeruginosa (P. aeruginosa), then studied its pulmonary inflammatory reaction and analyzed the concentration of lipids and SP-A in bronchoalveolar lavage fluid (BALF) during infection.

  7. Pseudomonas aeruginosa Biofilms

    DEFF Research Database (Denmark)

    Alhede, Maria; Bjarnsholt, Thomas; Givskov, Michael

    2014-01-01

    The opportunistic gram-negative bacterium Pseudomonas aeruginosa is implicated in many chronic infections and is readily isolated from chronic wounds, medical devices, and the lungs of cystic fibrosis patients. P. aeruginosa is believed to persist in the host organism due to its capacity to form...... (PMNs). In this chapter, the interplay between P. aeruginosa and the PMNs in chronic infections is discussed with focus on the role of rhamnolipids and extracellular DNA....

  8. Pseudomonas Aeruginosa Toxins

    Science.gov (United States)

    1982-09-01

    circulatory collapse, and leucopenia . These observations were similar to those made in Pseudomonas infections. This work resulted in great stimulation...Sensakovic and Bartell (1974) reported that a toxic slime fraction caused leucopenia in mice, and the relative contribution of these factors and of exotoxin...A to leucopenia remains to be determined. Finally. the low incidence of leucocidin producing strains argue against any significant importance of

  9. Population Structure of Pseudomonas aeruginosa

    National Research Council Canada - National Science Library

    Lutz Wiehlmann; Gerd Wagner; Nina Cramer; Benny Siebert; Peter Gudowius; Gracia Morales; Thilo Köhler; Christian van Delden; Christian Weinel; Peter Slickers; Burkhard Tümmler

    2007-01-01

    The metabolically versatile Gram-negative bacterium Pseudomonas aeruginosa inhabits terrestrial, aquatic, animal-, human-, and plant-host-associated environments and is an important causative agent...

  10. Uptaking and Biodegradation of Alkane by Two Pseudomonas Strains%两株假单胞菌对烷烃的摄取和降解

    Institute of Scientific and Technical Information of China (English)

    杨国君; 宋若海; 华兆哲; 李华钟; 陈坚

    2005-01-01

    根据细菌在油水混合体系中的分布差异,从江苏油田附近污染的土样中筛选得到了两株对烷烃具有降解能力的假单胞菌Pseudomonas sp.A和Pseudomonas sp.B.在以煤油为唯一碳源的培养基中,Pseudomonas sp.A的生长量较低,菌体主要聚集在油相中,菌体细胞呈亲油性,生长几乎不受生物表面活性剂抑制剂EDTA的影响,菌体的生长对培养基的表面张力的降低幅度较小;而Pseudomonas sp.B则表现相反的性质.说明两菌株对烷烃具有不同的摄取机制,Pseudomonas sp.A是以直接接触烷烃的方式摄取,而Pseudomonas sp.B则是通过产生生物表面活性剂对烷烃进行乳化后再摄取.

  11. Metabolic Control Analysis of L-Cysteine Enzymatic Synthesis Pathway in Pseudomonas sp. Strain TS1138%假单胞菌TS1138菌株L-半胱氨酸酶法合成途径的代谢控制分析

    Institute of Scientific and Technical Information of China (English)

    怀丽华; 陈宁; 杨文博; 白钢

    2008-01-01

    建立了假单胞菌TS1138菌株L-半胱氨酸酶法合成途径的动力学模型.在L-半胱氨酸合成途径中有L-半胱氨酸合成酶和L-半胱氨酸脱巯基酶两种酶参与作用,它们的动力学模型是基于米氏动力学建立的,L-半胱氨酸对L-半胱氨酸合成酶有非竞争性抑制作用.通过测定L-半胱氨酸酶法合成过程中的中间产物和终产物的浓度,利用动力学模型进行了L-半胱氨酸合成途径的代谢控制分析.弹性系数首先可以从动力学方程中求出,根据代谢控制分析理论,流量控制系数由弹性系数求出.研究发现,在L-半胱氨酸酶法合成过程中,L-半胱氨酸合成酶和L-半胱氨酸脱巯基酶的流量控制系数存在一个交叉点.%A kinetic model describing the pathway for the L-cysteine enzymatic synthesis by Pseudomonas sp. strain TS1138 has been developed. In the synthesis pathway, both the L-cysteine synthetase (CS) and the L-cysteine desulfhydrase (CD) were involved with the kinetic model based on Michaelis-Menten type kinetics, and also on noncompetitive inhibition of the CS by L-cysteine. From the determination of intermediates and end products during the process of L-cysteine enzymatic synthesis, with the kinetic model, metabolic control analysis (MCA) of the pathway was carried out. From the kinetic model, the elasticity coefficients and the flux control coefficients were calculated through the pathway. It was found that there is a shift in the flux control from the CS to the CD during the enzymatic reaction.

  12. Construction of Pseudomonas sp.M18 relA mutant and its regulation on phenazine-1-carboxylic acid biosynthesis%假单胞菌M18relA突变株的构建及其对吩嗪-1-羧酸合成的调控

    Institute of Scientific and Technical Information of China (English)

    王金英; 张明月; 王国昊; 魏雪; 李雅乾; 黄显清; 许煜泉

    2011-01-01

    The rhizosphere bacterium Pseudomonas sp. M 18 can simultaneously produce two antibiotics:phenazine-1- carboxylic acid (PCA) and pyoluteorin. ppGpp, which is synthesized by Re1A, can mediate bacterial stringent response to nutritional starvation. The relA gene was PCR amplified from the M18 strain chromosomal DNA template. The relA mutant of M18 strain (M18RAG) was constructed through inserted inactivation of gentamicin resistance cassette and homologous recombination. PCA production was assayed in PPM media. It was showed that the relA mutation resulted in a significant enhancement of PCA production. PCA production of M 18RAG was about 1.5 to 2 times as much as that of the wild-type strain. The negative regulation of RelA on PCA biosynthesis and its gene expression was further confirmed by the trans complementation test of relA gene and the expression analysis of phzA '-'lacZ translational fusion.%假单胞菌M18是一株能同时合成吩嗪-1-羧酸(PCA)和藤黄绿菌素两种抗生素的植物根际分离细菌.RelA催化合成的效应分子ppGpp能介导细菌因营养饥饿引起的应激反应.以M18菌株染色体DNA为模板,PCR扩增获得relA基因,通过庆大霉素抗性片段插入失活与同源重组技术,构建假单胞菌M18的relA突变菌株M18RAG.在PPM培养基中进行PCA发酵分析,发现突变菌株M18RAG的PCA产量显著升高,约为野生型菌株的1.5-2倍.relA基因反式互补实验以及phzA'-'lacZ翻译融合测定结果,均进一步证明了RelA对PCA生物合成及其基因表达具有抑制作用.

  13. Bioremediation of Chromium (VI from Textile Industry’s Effluent and Contaminated Soil Using Pseudomonas putida

    Directory of Open Access Journals (Sweden)

    Deepali

    2011-01-01

    Full Text Available Nine bacterial colonies were screened for the Cr(VI removal efficiency and out of these three bacterial strains Pseudomonas putida, Pseudomonas aeruginosa and Bacillus sp. were isolated from soil and used to remove Cr(VI from aqueous solution. The effect of time and concentrations on the removal rate of hexavalent chromium were studied using batch experiment. Maximum Cr (VI removal was noted 75.0% by Bacillus sp. at 10mg/l, 69.70% by Pseudomonas aeruginosa at 40mg/l and 90.88% by Pseudomonas putida at 10mg/l of synthetic solution, during 96 hours. Among these three bacteria, the maximum Cr(VI removal was reported by Pseudomonas putida on lower concentration. On the basis of highest removal rate, Pseudomonas putida was selected and used for further chromium removal from samples. It was found to be removed the highest Cr(VI by 82.92%, from effluent and 74.41% from soil during 96 hours. The present study depicts that bacteria removes chromium efficiently and this could be used for industrial waste management and other environmental contaminants.

  14. Pseudomonas genomes: diverse and adaptable.

    Science.gov (United States)

    Silby, Mark W; Winstanley, Craig; Godfrey, Scott A C; Levy, Stuart B; Jackson, Robert W

    2011-07-01

    Members of the genus Pseudomonas inhabit a wide variety of environments, which is reflected in their versatile metabolic capacity and broad potential for adaptation to fluctuating environmental conditions. Here, we examine and compare the genomes of a range of Pseudomonas spp. encompassing plant, insect and human pathogens, and environmental saprophytes. In addition to a large number of allelic differences of common genes that confer regulatory and metabolic flexibility, genome analysis suggests that many other factors contribute to the diversity and adaptability of Pseudomonas spp. Horizontal gene transfer has impacted the capability of pathogenic Pseudomonas spp. in terms of disease severity (Pseudomonas aeruginosa) and specificity (Pseudomonas syringae). Genome rearrangements likely contribute to adaptation, and a considerable complement of unique genes undoubtedly contributes to strain- and species-specific activities by as yet unknown mechanisms. Because of the lack of conserved phenotypic differences, the classification of the genus has long been contentious. DNA hybridization and genome-based analyses show close relationships among members of P. aeruginosa, but that isolates within the Pseudomonas fluorescens and P. syringae species are less closely related and may constitute different species. Collectively, genome sequences of Pseudomonas spp. have provided insights into pathogenesis and the genetic basis for diversity and adaptation.

  15. [Pseudomonas aeruginosa in dermatology].

    Science.gov (United States)

    Morand, A; Morand, J-J

    2017-08-01

    Pseudomonas aeruginosa, a ubiquitous Gram-negative bacillus characterized by its greenish color and sweetish smell, is at the origin of potentially severe forms of dermatosis, such as ecthyma gangrenosum which marks immunosuppression or reveals blood-poisoning, especially in children. It frequently colonizes chronic wounds and serious burns, and spongiotic or acantholytic dermatosis, especially when severe or localized in skinfolds. It requires special care because of its high resistance to antibiotics and antiseptics. It can also involve folliculitis favored by water sports or a nail disorder (chloronychia). Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  16. Diversity among Pseudomonas syringae strains originating from fruit trees in Serbia

    Directory of Open Access Journals (Sweden)

    Ivanović Žarko

    2009-01-01

    Full Text Available Pseudomonas syringae is a widespread and economically important plant pathogen, one found on a number of hosts, including fruit trees, field crops, vegetables, and ornamental plants. This bacterium has been experimentally identified as a parasite of pear, apple, apricot, peach, cherry, sour cherry, plum, and raspberry. The present study was designed to establish differences between strains isolated from fruit trees in Serbia. The pathogenic and biochemical characteristics of isolates were studied. The BOX-PCR method was used to generate genomic fingerprints of Pseudomonas syringae isolates and to identify strains that were previously not distinguishable by other classification methods. Different Bacillus sp. strains were tested for in vitro inhibitory activity against Pseudononas syringae isolates. Bacillus sp. strains show inhibitory activity only against P. syringae isolates that originated from peach. The obtained results demonstrate that the population of the bacterium Pseudomonas syringae from the fruit trees in Serbia is very diverse.

  17. Biosynthetic Origin of the Antibiotic Cyclocarbamate Brabantamide A (SB-253514) in Plant-Associated Pseudomonas

    NARCIS (Netherlands)

    Schmidt, Y.; van der Voort, M.; Crüsemann, M.; Piel, J.; Josten, M.; Sahl, H.-G.; Miess, H.; Raaijmakers, J.M.; Gross, H.

    2014-01-01

    Within the framework of our genome-based program to discover new antibiotic lipopeptides from Pseudomonads, brabantamides A–C were isolated from plant-associated Pseudomonas sp. SH-C52. Brabantamides A–C displayed moderate to high in vitro activities against Gram-positive bacterial pathogens. Their

  18. Environmental and molecular regulation of phenazine-1-carboxamide biosynthesis in Pseudomonas chlororaphis strain PCL1391

    NARCIS (Netherlands)

    Rij, Evert Tjeerd van

    2006-01-01

    The biocontrol strain studied in this thesis is Pseudomonas chlororaphis strain PCL1391, which controls tomato foot and root rot caused by Fusarium oxysporum f. sp. radicis-licopersici (Chin-A-Woeng et al., 1998). Production of the anti-fungal metabolite phenazine-1-carboxamide (PCN) and an efficien

  19. Biosynthetic Origin of the Antibiotic Cyclocarbamate Brabantamide A (SB-253514) in Plant-Associated Pseudomonas

    NARCIS (Netherlands)

    Schmidt, Y.; Voort, van der M.; Crüsemann, M.; Piel, J.; Josten, M.; Sahl, H.G.; Miess, H.; Raaijmakers, J.M.; Gross, H.

    2014-01-01

    Within the framework of our genome-based program to discover new antibiotic lipopeptides from Pseudomonads, brabantamides A–C were isolated from plant-associated Pseudomonas sp. SH-C52. Brabantamides A–C displayed moderate to high in vitro activities against Gram-positive bacterial pathogens. Their

  20. Novel Pseudomonas – derived antifungal lipopeptides from a disease suppressive soil in Greenlandic potato fields

    DEFF Research Database (Denmark)

    Hennessy, Rosanna Catherine; Michelsen, Charlotte Frydenlund; Glaring, Mikkel Andreas

    suppressive and a source of diverse bacteria with antifungal activity. Using culture-based approaches, the strain Pseudomonas sp. In5 was identified from the soil microbiome shown to have potent antifungal activity. A combination of molecular genetics and genomics coupled with matrix-assisted laser desorption...

  1. PSYCHROPHILIC PSEUDOMONAS SP. RESISTANT TO MERCURY FROM PAVLODAR, KAZAKHSTAN

    Science.gov (United States)

    As mercury circulates and deposits globally, the remediation of extensive mercury contamination surrounding a chloralkali plant in Pavlodar, Kazakhstan is critical. High-levels of mercury contamination exist within the confines of the plant, at nearby off-site waste storage and e...

  2. Antimicrobial activities of rhizobacterial strains of Pseudomonas and Bacillus strains isolated from rhizosphere soil of carnation (Dianthus caryophyllus cv. Sunrise)

    OpenAIRE

    Sharma, Sapna; Kaur, Mohinder

    2010-01-01

    Under the present study, an attempt was made to characterize rhizobacteria i.e. Pseudomonas and Bacillus species isolated from rhizosphere of carnation to evaluate their growth promoting effect on carnation so as to select and develop more efficient indigenous plant growth promoting and disease suppressing bioagents of specific soil type and specific plant type. Maximum strains of Pseudomonas and Bacillus sp. showed significant antimicrobial activities against most of the microorganisms teste...

  3. Pseudomonas aeruginosa biofilm infections

    DEFF Research Database (Denmark)

    Tolker-Nielsen, Tim

    2014-01-01

    Bacteria in natural, industrial and clinical settings predominantly live in biofilms, i.e., sessile structured microbial communities encased in self-produced extracellular matrix material. One of the most important characteristics of microbial biofilms is that the resident bacteria display...... a remarkable increased tolerance toward antimicrobial attack. Biofilms formed by opportunistic pathogenic bacteria are involved in devastating persistent medical device-associated infections, and chronic infections in individuals who are immune-compromised or otherwise impaired in the host defense. Because...... the use of conventional antimicrobial compounds in many cases cannot eradicate biofilms, there is an urgent need to develop alternative measures to combat biofilm infections. The present review is focussed on the important opportunistic pathogen and biofilm model organism Pseudomonas aeruginosa. Initially...

  4. Chronic Pseudomonas aeruginosa cervical osteomyelitis

    Directory of Open Access Journals (Sweden)

    Sujeet Kumar Meher

    2016-01-01

    Full Text Available Pseudomonas aeruginosa is a rare cause of osteomyelitis of the cervical spine and is usually seen in the background of intravenous drug use and immunocompromised state. Very few cases of osteomyelitis of the cervical spine caused by pseudomonas aeruginosa have been reported in otherwise healthy patients. This is a case presentation of a young female, who in the absence of known risk factors for cervical osteomyelitis presented with progressively worsening neurological signs and symptoms.

  5. Screening for Pseudomonas and Bacillus antagonistic rhizobacteria strains for the biocontrol of Fusarium wilt of chickpea

    Directory of Open Access Journals (Sweden)

    Hannane Abed

    2016-07-01

    Full Text Available The aim of this work is to study the ability of several isolates belonging to Rhizobacteria (Pseudomonas and Bacillus collected from several chickpea growing areas in Algeria, to control the mycelium growth of Fusarium oxysporum f. sp. ciceris. Interesting isolates were characterized for their morphological characteristics, physiological and biochemical activities as potential bio-control agent. Fungal inhibition tests were performed using plate assay and each isolate were tested for the production of protease, cyanide hydrogen, indole acetic acid, antifungal volatile and extracellular compound. According to API 50 CH, we are able to identify six Bacillus species (B. subtilis, B. circulans, B. lentus, B. aneurinilyticus, B. firmus, B. licheniformis; and with API 20NE test we have identified three Pseudomonas species (P. aeruginosa, P. luteola, P. fluorescens. The ability of bacterial isolates was varied in production of Protease, Gelatinase, Amylase, Cellulase, Acid Indole acetic, Lipase, Catalase and Cyanid Hydrogen. This is traduced in different rate of inhibition growth due to various extracellular compounds, where B61 (Bacillus aneurinilyticus and P39 (Pseudomonas luteola and P70 (Pseudomonas fluorescens were the most efficient with 77 and 55.5% respectively, while B39 (Bacillus firmus and P41 (Pseudomonas luteola were the most efficient by volatile compounds with 70.5 and 77.5% respectively. Our results indicate that these bacteria isolates can be used in the biocontrol of Fusarium oxysporum f. sp. ciceris.

  6. Pengaruh konsentrasi nitrogen dan fosfor terhadap potensi pseudomonas pendegradasi alkilbenzen sulfonat liniar (LAS

    Directory of Open Access Journals (Sweden)

    J Suharjono

    2012-02-01

    Full Text Available Linear Alkylbenzene Sulfonate (LAS concentration over 0.5 mg/L has toxic effect on organisms in river ecosystem. Some indigenous Pseudomonas strains on detergent polluted river have capacity to degraded LAS. The objective of the research was to study the effect of increasing of nitrogen (N and phosphorus (P concentration in minimum mineral medium on growth and LAS biodegradation potency of Pseudomonas strains using batch culture. The experiment was carried out by Randomized Block Design and three replications. Each three milliliter of strain starter contain 108 cell/ml was inoculated into 27 ml of each media formulation. Each culture was incubated aerobically at 30 oC on shaker incubator. Amount of bacteria cell and LAS residue concentration were observed on 0, 3rd, 6th, 9th and 12th day incubation. Data was analyzed using variance analyze and followed by Honesty Significance Difference test on 5% significance level. The result of the research showed that Pseudomonas putida FNCC071, Pseudomonas sp. strain R, and Pseudomonas sp. strain J was capable to degrade LAS about 89.0%, 87.0% and 80.0% respectively in 12 days incubation. The highest increasing of N and P concentration in media gives the highest potency of bacteria strains to degrade LAS (p > 0.05.

  7. Draft Genome Sequence of Pedobacter sp. Strain V48, Isolated from a Coastal Sand Dune in the Netherlands

    NARCIS (Netherlands)

    Bitzer, A.S.; Garbeva, P.V.; Silby, M.W.

    2014-01-01

    Pedobacter sp. strain V48 participates in an interaction with Pseudomonas fluorescens which elicits interaction-induced phenotypes. We report the draft genome sequence of Pedobacter sp. V48, consisting of 6.46 Mbp. The sequence will contribute to improved understanding of the genus and facilitate

  8. Antifungal activity and genetic diversity of selected Pseudomonas spp. from maize rhizosphere in Vojvodina

    Directory of Open Access Journals (Sweden)

    Jošić Dragana

    2012-01-01

    Full Text Available Antibiotic production by plant-associated microorganisms represents an environmentally compatible method of disease control in agriculture. However, a vide application of bacterial strains needs careful selection and genetic characterization. In this investigation, selected Pseudomonas strains were characterized by rep-PCR methods using ERIC and (GTG5 primers, and partial 16S rDNA sequence analysis. None of strains produced homoserine lactones (C4, C6, C8 as quorum sensing signal molecules. Very poor production of phenazines and no significant fungal inhibition was observed for PS4 and PS6 strains. High amount of phenazines were produced by Pseudomonas sp. strain PS2, which inhibited mycelial growth of 10 phytopatogenic fungi in percent of 25 (Verticillium sp. to 65 (Fusarium equiseti. Genetic characterization of the Pseudomonas sp. PS2 and evaluation of phenazines production, as the main trait for growth inhibition of phytopathogenic fungi, will allow its application as a biosafe PGPR for field experiments of plant disease control. [Projekat Ministarstva nauke Republike Srbije, br. III 46007: New indigenous bacterial isolates Lysobacter and Pseudomonas as an important sources of metabolites useful for biotechnology, plant growth stimulation and disease control: From isolates to inoculants

  9. SP. Pescado

    Directory of Open Access Journals (Sweden)

    Renato Gendre

    2003-12-01

    Full Text Available Nell'occhiello di un articolo dal titolo Il Peru dei de[Jini rosa e de/la grande pioggia si legge: "da una partenza  in aereo al «pescado»  che ti  sfamera."1 Questa parola spagnola, giustamente chiusa tra caporali, a noi pare molto interes­ sante, perche, nonostante l'apparenza, non ha nulla da spartire sotto i1 profilo se­ mantico con l'it. pescato. lnfatti, tutti i piu importanti dizionari della lingua italiana, di ieri e di oggi, etimologici e non 2, registrano  accanto a pescata,  ii lemma pescato, 3 ma lo spiegano come "quantita di pesce catturato nel corso di una battuta o di una stagione di pesca",4 mentre lo sp. pescado  indica i1 "pesce (solo nel senso di: pesGe pescato da mangiare [...]".s

  10. Biosorption of heavy metals by Pseudomonas species isolated from sugar industry.

    Science.gov (United States)

    Naz, Tayyaba; Khan, Muhammad Daud; Ahmed, Iftikhar; Rehman, Shafiq Ur; Rha, Eui Shik; Malook, Ijaz; Jamil, Muhammad

    2016-09-01

    Heavy metal-resistant bacteria can be efficient bioremediators of metals and may provide an alternative or additional method to conventional methods of metal removal. In this study, 10 bacterial isolates were isolated from soil samples of a sugar industry, located at Peshawar, Pakistan. Morphological, physiological, and biochemical characteristics of these isolates were observed. Sequence analysis (16S ribosomal RNA) revealed that isolated strains were closely related to the species belonging to the genera Pseudomonas, Arthrobacter, Exiguobacterium, Citrobacter, and Enterobacter Bacterial isolates were resistant with a minimum inhibitory concentration (500-900 ppm) to lead ion (Pb(2+)), (500-600 ppm) nickel ion (Ni(2+)), (500-800 ppm) copper ion (Cu(2+)), and (600-800 ppm) chromium ion (Cr(3+)) in solid media. Furthermore, biosorption of metals proved considerable removal of heavy metals by isolated metal-resistant strains. Pseudomonas sp. reduced 37% (Pb(2+)), 32% (Ni(2+)), 29% (Cu(2+)), and 32% (Cr(3+)) and was thus found to be most effective, whereas Enterobacter sp. reduced 19% (Pb(2+)), 7% (Ni(2+)), 14% (Cu(2+)), and 21% (Cr(3+)) and was found to be least effective. While average reduction of Pb(2+), Ni(2+), Cu(2+), and Cr(3+) by Citrobacter sp. was found to be 24%, 18%, 23%, and 27%, respectively, among recognized species. This study revealed that Pseudomonas sp. may provide a new microbial community that can be used for enhanced remediation of contaminated environment.

  11. Hot Tub Rash (Pseudomonas Dermatitis/Folliculitis)

    Science.gov (United States)

    ... Español [PDF - 1 page] "Hot Tub Rash" ( Pseudomonas Dermatitis / Folliculitis) If contaminated water comes in contact ... is often caused by infection with the germ Pseudomonas aeruginosa . This germ is common in the environment ( ...

  12. The Pseudomonas Quinolone Signal (PQS)

    DEFF Research Database (Denmark)

    Sams, Thomas; Baker, Ysobel; Hodgkinson, James

    2015-01-01

    Pseudomonas aeruginosa is an opportunistichuman pathogen that routinely appears near the top ofpublic health threat lists worldwide. P. aeruginosa causes in-fections by secreting a wealth of exceptionally active exo-products, leading to tissue damage. The synthesis of manyof these virulence factors...

  13. Reduction of Fusarium wilt in watermelon by Pseudomonas chlororaphis PCL1391 and P. fluorescens WCS365

    Directory of Open Access Journals (Sweden)

    G.T. Tziros

    2007-12-01

    Full Text Available Fusarium wilt of watermelon (Citrullus lanatus caused by Fusarium oxysporum f. sp. niveum is a devastatine soil-borne disease that causes extensive losses throughout the world. Two known Pseudomonas biocontrol strains were used separately and in combination to assess their antagonistic effectiveness against F. oxysporum f. sp. niveum in pot experiments. P. chlororaphis PCL1391 signifi cantly reduced disease severity. P. fl uorescens WCS365 was less effective in disease suppression, while a combination of the two bacteria had intermediate effects. The biological control of Fusarium wilt with P. chlororaphis offers a potentially useful tool in an integrated pest management program to control Fusarium wilt of watermelon.

  14. Genetic Lineages and Antimicrobial Resistance in Pseudomonas spp. Isolates Recovered from Food Samples.

    Science.gov (United States)

    Estepa, Vanesa; Rojo-Bezares, Beatriz; Torres, Carmen; Sáenz, Yolanda

    2015-06-01

    Raw food is a reservoir of Pseudomonas isolates that could be disseminated to consumers. The presence of Pseudomonas spp. was studied in food samples, and the phenotypic and genotypic characterizations of the recovered isolates were analyzed. Two samples of meat (3%, turkey and beef) and 13 of vegetables (22%, 7 green peppers and 6 tomatoes) contained Pseudomonas spp. A total of 20 isolates were identified, and were classified as follows (number of isolates): P. aeruginosa (5), P. putida (5), P. nitroreducens (4), P. fulva (2), P. mosselli (1), P. mendocina (1), P. monteilii (1), and Pseudomonas sp. (1). These 20 Pseudomonas isolates were clonally different by pulsed-field-gel-electrophoresis, and were resistant to the following antibiotics: ticarcillin (85%), aztreonam (30%), cefepime (10%), imipenem (10%), and meropenem (5%), but were susceptible to ceftazidime, piperacillin, piperacillin-tazobactam, doripenem, gentamicin, tobramycin, amikacin, ciprofloxacin, norfloxacin, and colistin. Only one strain (Ps158) presented a class 1 integron lacking the 3' conserved segment. The five P. aeruginosa strains were typed by multilocus sequence typing in five different sequence-types (ST17, ST270, ST800, ST1455, and ST1456), and different mutations were detected in protein OprD that were classified in three groups. One strain (Ps159) showed a new insertion sequence (ISPa47) truncating the oprD gene, and conferring resistance to imipenem.

  15. Cyanide production by Pseudomonas fluorescens and Pseudomonas aeruginosa.

    Science.gov (United States)

    Askeland, R A; Morrison, S M

    1983-06-01

    Of 200 water isolates screened, five strains of Pseudomonas fluorescens and one strain of Pseudomonas aeruginosa were cyanogenic. Maximum cyanogenesis by two strains of P. fluorescens in a defined growth medium occurred at 25 to 30 degrees C over a pH range of 6.6 to 8.9. Cyanide production per cell was optimum at 300 mM phosphate. A linear relationship was observed between cyanogenesis and the log of iron concentration over a range of 3 to 300 microM. The maximum rate of cyanide production occurred during the transition from exponential to stationary growth phase. Radioactive tracer experiments with [1-14C]glycine and [2-14C]glycine demonstrated that the cyanide carbon originates from the number 2 carbon of glycine for both P. fluorescens and P. aeruginosa. Cyanide production was not observed in raw industrial wastewater or in sterile wastewater inoculated with pure cultures of cyanogenic Pseudomonas strains. Cyanide was produced when wastewater was amended by the addition of components of the defined growth medium.

  16. Biosynthesis, chemical structure and structure-activity relationship of orfamide lipopeptides produced by Pseudomonas protegens and related species

    Directory of Open Access Journals (Sweden)

    Zongwang eMa

    2016-03-01

    Full Text Available Orfamide-type cyclic lipopeptides (CLPs are biosurfactants produced by Pseudomonas and involved in lysis of oomycete zoospores, biocontrol of Rhizoctonia and insecticidal activity against aphids. In this study we compared the biosynthesis, structural diversity, in vitro and in planta activities of orfamides produced by rhizosphere-derived Pseudomonas protegens and related Pseudomonas species. Genetic characterization together with chemical identification revealed that the main orfamide compound produced by the P. protegens group is orfamide A, while the related strains Pseudomonas sp. CMR5c and CMR12a produce orfamide B. Comparison of orfamide fingerprints led to the discovery of two new orfamide homologues (orfamide F and orfamide G in Pseudomonas sp. CMR5c. The structures of these two CLPs were determined by nuclear magnetic resonance (NMR and mass spectrometry (MS analysis. Mutagenesis and complementation showed that orfamides determine the swarming motility of parental Pseudomonas sp. strain CMR5c and their production was regulated by luxR type regulators. Orfamide A and orfamide B differ only in the identity of a single amino acid, while orfamide B and orfamide G share the same amino acid sequence but differ in length of the fatty acid part. The biological activities of orfamide A, orfamide B and orfamide G were compared in further bioassays. The three compounds were equally active against Magnaporthe oryzae on rice, against Rhizoctonia solani AG 4-HGI in in vitro assays, and caused zoospore lysis of Phytophthora and Pythium. Furthermore we could show that orfamides decrease blast severity in rice plants by blocking appressorium formation in M. oryzae. Taken all together, our study shows that orfamides produced by P. protegens and related species have potential in biological control of a broad spectrum of fungal plant pathogens.

  17. Actinobacteria associated with the marine sponges Cinachyra sp., Petrosia sp., and Ulosa sp. and their culturability.

    Science.gov (United States)

    Khan, Shams Tabrez; Takagi, Motoki; Shin-ya, Kazuo

    2012-01-01

    Actinobacteria associated with 3 marine sponges, Cinachyra sp., Petrosia sp., and Ulosa sp., were investigated. Analyses of 16S rRNA gene clone libraries revealed that actinobacterial diversity varied greatly and that Ulosa sp. was most diverse, while Cinachyra sp. was least diverse. Culture-based approaches failed to isolate actinobacteria from Petrosia sp. or Ulosa sp., but strains belonging to 10 different genera and 3 novel species were isolated from Cinachyra sp.

  18. Impacts of some divalent cations on periplasmic nitrate reductase and dehydrogenase enzymes of Escherichia, Pseudomonas and Acinetobacter species

    Directory of Open Access Journals (Sweden)

    Christian E. Nwanyanwu

    2008-08-01

    Full Text Available The impacts of Hg2+, Cd2+ and Zn2+ on the activities of periplasmic nitrate reductase (NAP and dehydrogenase (DHA enzymes of three organisms isolated from soil and sediment-water interface were analysed in liquid culture studies. NAP and DHA activities were estimated from nitrite and triphenyl formazan were produced respectively after 4h incubation at 28 ± 2oC. Hg2+ completely inhibited NAP activity in Escherichia and Pseudomonas spp at all the concentrations (0.2 – 1mM while progressive inhibitions of NAP activity were observed in Escherichia and Pseudomonas spp with increasing concentrations of Zn2+ and Cd2+. Both metals were stimulatory to NAP of Acinetobacter sp at 0.2 – 1mM. Apart from stimulation of DHA activity by Zn2+ (0.2 – 1mM in Escherichia sp, Cd2+ (0.4 -1.0mM in Acinetobacter sp and (1.0mM in Pseudomonas sp, all the metals progressively inhibited DHA activities in the three organisms. In Escherichia sp, the activities of the two enzymes were negatively correlated on exposure to Zn2+ (r = -0.91 and positively correlated (r = >0.90 on exposure to Cd2+ and Hg2+. Based on IC50 values of the metals for the DHA and NAP enzymes, the most resistant of the three organisms were Escherichia sp and Acinetobacter sp respectively. Quantitatively, NAP with its lower IC50 values than DHA was a more sensitive toxicity measure for Hg2+ in all the organisms. The sensitivity of microbial metabolic enzymes to the toxic effects of metals varies with the type of enzyme, metal and the microorganism involved.

  19. Biocontrol traits of Pseudomonas spp. are regulated by phase variation.

    Science.gov (United States)

    van den Broek, Daan; Chin-A-Woeng, Thomas F C; Eijkemans, Kevin; Mulders, Ine H M; Bloemberg, Guido V; Lugtenberg, Ben J J

    2003-11-01

    Of 214 Pseudomonas strains isolated from maize rhizosphere, 46 turned out to be antagonistic, of which 43 displayed clear colony phase variation. The latter strains formed both opaque and translucent colonies, designated as phase I and phase II, respectively. It appeared that important biocontrol traits, such as motility and the production of antifungal metabolites, proteases, lipases, chitinases, and biosurfactants, are correlated with phase I morphology and are absent in bacteria with phase II morphology. From a Tn5luxAB transposon library of Pseudomonas sp. strain PCL1171 phase I cells, two mutants exhibiting stable expression of phase II had insertions in gacS. A third mutant, which showed an increased colony phase variation frequency was mutated in mutS. Inoculation of wheat seeds with PCL1171 bacteria of phase I morphology resulted in efficient suppression of take-all disease, whereas disease suppression was absent with phase II bacteria. Neither the gacS nor the mutS mutant was able to suppress take-all, but biocontrol activity was restored after genetic complementation of these mutants. Furthermore, in a number of cases, complementation by gacS of wild-type phase II sectors to phase I phenotype could be shown. A PCL1171 phase I mutant defective in antagonistic activity appeared to have a mutation in a gene encoding a lipopeptide synthetase homologue and had lost its biocontrol activity, suggesting that biocontrol by strain PCL1171 is dependent on the production of a lipopeptide. Our results show that colony phase variation plays a regulatory role in biocontrol by Pseudomonas bacteria by influencing the expression of major biocontrol traits and that the gacS and mutS genes play a role in the colony phase variation process. Therefore phase variation not only plays a role in escaping animal defense but it also appears to play a much broader and vital role in the ecology of bacteria producing exoenzymes, antibiotics, and other secondary metabolites.

  20. Crestamento bacteriano em filodendro causado por Pseudomonas cichorií.

    Directory of Open Access Journals (Sweden)

    Valdemar A. Malavolta Júnior

    2001-05-01

    Full Text Available É descrita a ocorrência de Pseudomonas cichorii causando lesões foliares ligeiramente circulares e de tamanho variável, em plantas de diversos cultivares de filodendro (Philodendron spp., provenientes de viveiro comercial localizado no município de Holambra (SP, e cultivados sob cobertura plástica. Essas manchas, pardo-escuras, podiam atingir até 7 a 8 cm de diâmetro, verificando-se, em alguns casos, coalescência de lesões, acarretando intenso crestamento foliar. Essa é a primeira constatação de Pseudomonas cichorii em filodendro no Brasil. Isolados encontram-se depositados na Coleção de Culturas do Instituto Biológico, Seção de Bacteriologia Fitopatológica (IBSBF sob n.ºs 1262 e 1263. Diferentes graus de resistência foram observados entre os cultivares de filodendro. O ‘Amarelo’ foi o mais resistente, enquanto P. scandens e os cultivares Boulevard e Red Emerald, além de quatro outros não identificados, mostraram alta suscetibilidade.

  1. Study on Antibiotic compounds from Pseudomonas aeruginosa NO4 Strain

    Energy Technology Data Exchange (ETDEWEB)

    Nam, Ji Young; Kim, Jin Kyu [Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of)

    2011-05-15

    As important human and veterinary medicines, antibiotics are being produced and consumed in large quantities around the world. For example, more than 50 million pounds (22,000 tons) of antibiotics are produced in the U.S. each year and annual production in Germany is about 2,000 tons. Antibiotics are low molecular weight microbial metabolites that at low concentrations inhibit the growth of other microorganisms. Resistant bacteria may also spread and become broader infection-control problems, not only within health care institutions, but in communities as well. Clinically important bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA). MRSA is a common cause of infection among hospitalized patients. Pseudomonas aeruginosa is a major cause of opportunistic infections among immunocompromised individuals. The spread of this organism in health care settings is often difficult to control due to the presence of multiple intrinsic and acquired mechanisms of antimicrobial resistance. In this study, we isolated novel bacterium which had strong antagonistic activity and separated antibiotic compounds from Pseudomonas sp., and analyzed characteristics and molecular weight of the antibiotic compound

  2. Pseudomonas-follikulitis efter badning i spabad

    DEFF Research Database (Denmark)

    Uldall Pallesen, Kristine Appel; Andersen, Klaus Ejner; Mørtz, Charlotte Gotthard

    2012-01-01

    Pseudomonas aeruginosa is a rare cause of folliculitis. Pseudomonas folliculitis can develop after contact with contaminated water from swimming pools, hot tubs and spa baths. Systemic therapy may be indicated in patients with widespread lesions, systemic symptoms or in immunosuppressed patients...

  3. Genomics of Secondary Metabolism in Pseudomonas spp.

    Science.gov (United States)

    Pseudomonas is a heterogeneous genus of bacteria known for its ubiquity in natural habitats and its prolific production of secondary metabolites. The structurally diverse chemical structures produced by Pseudomonas spp. result from biosynthetic processes with unusual features that have revealed no...

  4. Studying Factors Involved in Biogenesis of Lysobacter sp. XL1 Outer Membrane Vesicles.

    Science.gov (United States)

    Kudryakova, I V; Suzina, N E; Vinokurova, N G; Shishkova, N A; Vasilyeva, N V

    2017-04-01

    The Gram-negative bacterium Lysobacter sp. XL1 produces outer membrane vesicles that are heterogeneous in size, density, and protein composition. One of the subpopulations is secretory vesicles for lytic protease L5 of Lysobacter sp. XL1 (Kudryakova et al. (2015) FEMS Microbiol. Lett., 362, fnv137). Protein L5 was assumed to influence biogenesis of these secretory vesicles that contain it. Using a Pseudomonas fluorescens Q2-87/B expression system, it was shown that the recombinant L5 protein may act as a factor of vesicle biogenesis. This points to a possible involvement of L5 protein in Lysobacter sp. XL1 vesicle biogenesis. Furthermore, it was established that the main phospholipid of Lysobacter sp. XL1 vesicles is cardiolipin, and vesicles are formed predominantly of outer membrane regions enriched with this phospholipid. This indicates that cardiolipin participates in biogenesis of all vesicle subpopulations in Lysobacter sp. XL1.

  5. Complex marine natural products as potential epigenetic and production regulators of antibiotics from a marine Pseudomonas aeruginosa.

    Science.gov (United States)

    Wang, Bin; Waters, Amanda L; Sims, James W; Fullmer, Alexis; Ellison, Serena; Hamann, Mark T

    2013-05-01

    Marine microbes are capable of producing secondary metabolites for defense and competition. Factors exerting an impact on secondary metabolite production of microbial communities included bioactive natural products and co-culturing. These external influences may have practical applications such as increased yields or the generation of new metabolites from otherwise silent genes in addition to reducing or limiting the production of undesirable metabolites. In this paper, we discuss the metabolic profiles of a marine Pseudomonas aeruginosa in the presence of a number of potential chemical epigenetic regulators, adjusting carbon sources and co-culturing with other microbes to induce a competitive response. As a result of these stressors certain groups of antibiotics or antimalarial agents were increased most notably when treating P. aeruginosa with sceptrin and co-culturing with another Pseudomonas sp. An interesting cross-talking event between these two Pseudomonas species when cultured together and exposed to sceptrin was observed.

  6. Antimicrobial Activity of Various Plant Extracts on Pseudomonas Species Associated with Spoilage of Chilled Fish

    Directory of Open Access Journals (Sweden)

    Osan Bahurmiz

    2016-11-01

    Full Text Available The antimicrobial activity of various plant extracts on Pseudomonas bacteria isolated from spoiled chilled tilapia (Oreochromis sp. was evaluated in this study. In the first stage of this study, red tilapia was subjected to chilled storage (4°C for 3 weeks, and spoilage bacteria were isolated and identified from the spoiled fish. Pseudomonas was the dominant bacteria isolated from the spoiled fish and further identification revealed that P. putida, P. fluorescens and Pseudomonas spp. were the main species of this group. In the second stage, methanolic extracts of 15 selected plant species were screened for their antimicrobial activity, by agar disc diffusion method, against the Pseudomonas isolates. Results indicated that most of the extracts had different degrees of activity against the bacterial isolates. The strongest activity was exhibited by bottlebrush flower (Callistemon viminalis extract. This was followed by extracts from guava bark (Psidium guajava and henna leaf (Lawsonia inermis. Moderate antimicrobial activities were observed in extracts of clove (Syzygium aromaticum, leaf and peel of tamarind (Tamarindus indica, cinnamon bark (Cinnamomum zeylanicum, wild betel leaf (Piper sarmentosum and fresh thyme (Thymus spp.. Weak or no antimicrobial activity was observed from the remaining extracts. The potential antimicrobial activity shown by some plant extracts in this study could significantly contribute to the fish preservation.

  7. Surveillance and Drug Resistance Analysis of Acinetobacter Sp. and Pseudomonas Aeruginosa Infection in a Hospital From 2013 to 2014%某院2013~2014年鲍曼不动杆菌及铜绿假单胞菌全院感染性监测及耐药性分析

    Institute of Scientific and Technical Information of China (English)

    崔敬惠

    2016-01-01

    Objective To explore the surveil ance and drug resistance of non fermenting bacteria acinetobacter bauman and pseudomonas aeruginosa in our hospital. Methods All kinds of various specimens from inpatient and outpatient were isolated and cultured and identified from January 2013 to December 2014 .The drug resistance of pathogenic bacteria was analyzed by using-NET 5.4 software in the world health organization(WHO). Results Bauman was divided into 312 strains of acinetobacter,1 364 pseudomonas aeruginosa from 2013 to 2014,most specimens were from sputum,the source of most clinical department is ICU,followed by department of respiration. pseudomonas aeruginosa resistant to compound sulfamethoxazole was 3.3%,for butylamine card that mildew,tobramycin,cefoperazone/sulbactam and levofloxacin resistance rate were 5%,5.3%, 5.5% and 9.4%,resistant to minocycline,ceftriaxone,cefotaxime was higher,respectively 56.8%,55.3%,45.6%,the resistance rate to other antimicrobial agents was 10% ~ 30%,bauman acinetobacter resistance to minocycline was 4.2%,to cefoperazone/sulbactam was 11.4%,to compound sulfamethoxazole resistance was the highest,was 51.9%,the drug resistance rate of other common drugs was 30% ~ 50%. Conclution The infection of pseudomonas aeruginosa and bauman is widespread,and the drug resistance is obvious. Clinical should strengthen the monitoring of drug resistance of these two kinds of hospital to prevent the spread of resistant strains.%目的:对我院常见的非发酵菌鲍曼不动杆菌和铜绿假单胞菌进行感染性监测并且对其耐药性进行分析。方法收集2013年1月~2014年12月住院和门诊患者送检的各类标本并进行分离培养和鉴定;采用世界卫生组织(WHO)-NET5.4软件对病原菌的耐药性进行分析。结果2013~2014年共分出鲍曼不动杆菌312株,铜绿假单胞菌1364株。标本来源均以痰液为主,临床科室来源最多的是 ICU,其次是呼吸科。铜绿假单胞菌对复

  8. Sp(2) Renormalization

    CERN Document Server

    Lavrov, Peter M

    2010-01-01

    The renormalization of general gauge theories on flat and curved space-time backgrounds is considered within the Sp(2)-covariant quantization method. We assume the existence of a gauge-invariant and diffeomorphism invariant regularization. Using the Sp(2)-covariant formalism one can show that the theory possesses gauge invariant and diffeomorphism invariant renormalizability to all orders in the loop expansion and the extended BRST symmetry after renormalization is preserved. The advantage of the Sp(2)-method compared to the standard Batalin-Vilkovisky approach is that, in reducible theories, the structure of ghosts and ghosts for ghosts and auxiliary fields is described in terms of irreducible representations of the Sp(2) group. This makes the presentation of solutions to the master equations in more simple and systematic way because they are Sp(2)- scalars.

  9. Sp(2) renormalization

    Energy Technology Data Exchange (ETDEWEB)

    Lavrov, Peter M., E-mail: lavrov@tspu.edu.r [Department of Mathematical Analysis, Tomsk State Pedagogical University, Kievskaya St. 60, Tomsk 634061 (Russian Federation)

    2011-08-11

    The renormalization of general gauge theories on flat and curved space-time backgrounds is considered within the Sp(2)-covariant quantization method. We assume the existence of a gauge-invariant and diffeomorphism invariant regularization. Using the Sp(2)-covariant formalism one can show that the theory possesses gauge-invariant and diffeomorphism invariant renormalizability to all orders in the loop expansion and the extended BRST-symmetry after renormalization is preserved. The advantage of the Sp(2) method compared to the standard Batalin-Vilkovisky approach is that, in reducible theories, the structure of ghosts and ghosts for ghosts and auxiliary fields is described in terms of irreducible representations of the Sp(2) group. This makes the presentation of solutions to the master equations in more simple and systematic way because they are Sp(2)-scalars.

  10. Fungicidal activities and mechanisms of action of Pseudomonas syringae pv. syringae lipodepsipeptide syringopeptins 22A and 25A

    Directory of Open Access Journals (Sweden)

    Mekki F. Bensaci

    2011-10-01

    Full Text Available The plant-associated bacterium Pseudomonas syringae pv. syringae simultaneously produces two classes of metabolites: the small cyclic lipodepsinonapeptides such as the syringomycins and the larger cyclic lipodepsipeptide syringopeptins SP22 or SP25. The syringomycins inhibit a broad spectrum of fungi (but particularly yeasts by lipid-dependent membrane interaction. The syringopeptins are phytotoxic and inhibitory to Gram positive bacteria. In this study, the fungicidal activities of two major syringopeptins, SP22A and SP25A, and their mechanisms of action were investigated and compared to those of syringomycin E. SP22A and SP25A were observed to inhibit the fungal yeasts Saccharomyces cerevisiae and Candida albicans although less effectively than syringomycin E. S. cerevisiae mutants defective in ergosterol and sphingolipid biosyntheses were less susceptible to SP22A and SP25A but the relative inhibitory capabilities of SRE vs. SP22A and SP25A were maintained. Similar differences were observed for capabilities to cause cellular K+ and Ca2+ fluxes in S. cerevisiae. Interestingly, in phospholipid bilayers the syringopeptins are found to induce larger macroscopic ionic conductances than syringomycin E but form single channels with similar properties. These findings suggest that the syringopeptins target the yeast plasma membrane, and, like syringomycin E, employ a lipid-dependent channel forming mechanism of action. The differing degrees of growth inhibition by these lipodepsipeptides may be explained by differences in their hydrophobicity. The more hydrophobic SP22A and SP25A might interact more strongly with the yeast cell wall that would create a selective barrier for their incorporation into the plasma membrane.

  11. Effects of Photoactivated Titanium Dioxide Nanopowders and Coating on Planktonic and Biofilm Growth of Pseudomonas aeruginosa

    DEFF Research Database (Denmark)

    Polo, Andrea; Diamanti, Maria Vittoria; Bjarnsholt, Thomas

    2011-01-01

    . A running protocol for the photoactivation of TiO(2) was set up using the dye rhodamine B. The microorganisms studied were Pseudomonas stutzeri, Pseudomonas aeruginosa and a Bacillus cereus-group as planktonic cells. P. aeruginosa biofilms were also studied at both the solid-liquid and the solid......-air interface. The TiO(2) nanopowder produced 1-log reduction of Bacillus sp. planktonic cells in 24 h, 2-log reduction of P. stutzeri planktonic cells in 30 min and 1-log reduction of P. aeruginosa planktonic cells in 2 h compared to non-photoactivated TiO(2) . TiO(2) thin film produced almost a complete...

  12. In vitro activity of moxalactam and mecillinam, singly and in combination, against multi-drug-resistant Enterobacteriaceae and Pseudomonas species.

    Science.gov (United States)

    Fass, R J

    1982-01-01

    The in vitro interaction of moxalactam and mecillinam against multi-drug-resistant gram-negative enteric bacilli was studied by checkerboard microdilution susceptibility tests and by killing curve kinetics. Against Enterobacteriaceae, the combination was unpredictable; the frequencies of synergy, indifference, and antagonism were 11, 76, and 13%, respectively. Against Pseudomonas sp., the two drugs were consistently indifferent. Overall, the combination of moxalactam and mecillinam was no more active than moxalactam alone.

  13. Resistance to Fusarium oxysporum f. sp. gladioli in transgenic Gladiolus plants expressing either a bacterial chloroperoxidase or fungal chitinase genes

    Science.gov (United States)

    Three antifungal genes, a non-heme chloroperoxidase from Pseudomonas pyrrocinia, and an exochitinase and endochitinase from Fusarium venetanum under regulation by the CaMV 35S promoter, were used to transform Gladiolus for resistance to Fusarium oxysporum f. sp. gladioli. Gladiolus plants were conf...

  14. Growth of genetically engineered Pseudomonas aeruginosa and Pseudomonas putida in soil and rhizosphere.

    OpenAIRE

    Yeung, K H; Schell, M A; Hartel, P G

    1989-01-01

    The effect of the addition of a recombinant plasmid containing the pglA gene encoding an alpha-1,4-endopolygalacturonase from Pseudomonas solanacearum on the growth of Pseudomonas aeruginosa and Pseudomonas putida in soil and rhizosphere was determined. Despite a high level of polygalacturonase production by genetically engineered P. putida and P. aeruginosa, the results suggest that polygalacturonase production had little effect on the growth of these strains in soil or rhizosphere.

  15. Silver against Pseudomonas aeruginosa biofilms

    DEFF Research Database (Denmark)

    Bjarnsholt, Thomas; Kirketerp-Møller, K.; Kristiansen, S.

    2007-01-01

    Silver has been recognized for its antimicrobial properties for centuries. Most studies on the antibacterial efficacy of silver, with particular emphasis on wound healing, have been performed on planktonic bacteria. Our recent studies, however, strongly suggest that colonization of wounds involves...... bacteria in both the planktonic and biofilm modes of growth. The action of silver on mature in vitro biofilms of Pseudomonas aeruginosa, a primary pathogen of chronic infected wounds, was investigated. The results show that silver is very effective against mature biofilms of P. aeruginosa......, but that the silver concentration is important. A concentration of 5-10 ig/mL silver sulfadiazine eradicated the biofilm whereas a lower concentration (1 ig/mL) had no effect. The bactericidal concentration of silver required to eradicate the bacterial biofilm was 10-100 times higher than that used to eradicate...

  16. Pseudomonas cichorii as the causal agent of midrib rot, an emerging disease of greenhouse-grown butterhead lettuce in Flanders.

    Science.gov (United States)

    Cottyn, Bart; Heylen, Kim; Heyrman, Jeroen; Vanhouteghem, Katrien; Pauwelyn, Ellen; Bleyaert, Peter; Van Vaerenbergh, Johan; Höfte, Monica; De Vos, Paul; Maes, Martine

    2009-05-01

    Bacterial midrib rot of greenhouse-grown butterhead lettuce (Lactuca sativa L. var. capitata) is an emerging disease in Flanders (Belgium) and fluorescent pseudomonads are suspected to play an important role in the disease. Isolations from infected lettuces, collected from 14 commercial greenhouses in Flanders, yielded 149 isolates that were characterized polyphasically, which included morphological characteristics, pigmentation, pathogenicity tests by both injection and spraying of lettuce, LOPAT characteristics, FAME analysis, BOX-PCR fingerprinting, 16S rRNA and rpoB gene sequencing, as well as DNA-DNA hybridization. Ninety-eight isolates (66%) exhibited a fluorescent pigmentation and were associated with the genus Pseudomonas. Fifty-five of them induced an HR+ (hypersensitive reaction in tobacco leaves) response. The other 43 fluorescent isolates were most probably saprophytic bacteria and about half of them were able to cause rot on potato tuber slices. BOX-PCR genomic fingerprinting was used to assess the genetic diversity of the Pseudomonas midrib rot isolates. The delineated BOX-PCR patterns matched quite well with Pseudomonas morphotypes defined on the basis of colony appearance and variation in fluorescent pigmentation. 16S rRNA and rpoB gene sequence analyses allowed most of the fluorescent isolates to be allocated to Pseudomonas, and they belonged to either the Pseudomonas fluorescens group, Pseudomonas putida group, or the Pseudomonas cichorii/syringae group. In particular, the isolates allocated to this latter group constituted the vast majority of HR+ isolates and were identified as P. cichorii by DNA-DNA hybridization. They were demonstrated by spray-inoculation tests on greenhouse-grown lettuce to induce the midrib rot disease and could be re-isolated from lesions of inoculated plants. Four HR+ non-fluorescent isolates associated with one sample that showed an atypical midrib rot were identified as Dickeya sp.

  17. Organic acid production in vitro and plant growth promotion in maize under controlled environment by phosphate-solubilizing fluorescent Pseudomonas

    Directory of Open Access Journals (Sweden)

    Vyas Pratibha

    2009-08-01

    Full Text Available Abstract Background Phosphorus deficiency is a major constraint to crop production due to rapid binding of the applied phosphorus into fixed forms not available to the plants. Microbial solubilization of inorganic phosphates has been attributed mainly to the production of organic acids. Phosphate-solubilizing microorganisms enhance plant growth under conditions of poor phosphorus availability by solubilizing insoluble phosphates in the soil. This paper describes the production of organic acids during inorganic phosphate solubilization and influence on plant growth as a function of phosphate solubilization by fluorescent Pseudomonas. Results Nineteen phosphate-solubilizing fluorescent Pseudomonas strains of P. fluorescens, P. poae, P. trivialis, and Pseudomonas spp. produced gluconic acid, oxalic acid, 2-ketogluconic acid, lactic acid, succinic acid, formic acid, citric acid and malic acid in the culture filtrates during the solubilization of tricalcium phosphate, Mussoorie rock phosphate, Udaipur rock phosphate and North Carolina rock phosphate. The strains differed quantitatively and qualitatively in the production of organic acids during solubilization of phosphate substrates. Cluster analysis based on organic acid profiling revealed inter-species and intra-species variation in organic acids produced by Pseudomonas strains. The phosphate-solubilizing bacterial treatments P. trivialis BIHB 745, P. trivialis BIHB 747, Pseudomonas sp. BIHB 756 and P. poae BIHB 808 resulted in significantly higher or statistically at par growth and total N, P and K content over single super phosphate treatment in maize. These treatments also significantly affected pH, organic matter, and N, P, and K content of the soil. Conclusion The results implied that organic acid production by Pseudomonas strains is independent of their genetic relatedness and each strain has its own ability of producing organic acids during the solubilization of inorganic phosphates

  18. Dynamics of Pseudomonas aeruginosa Genome Evolution

    National Research Council Canada - National Science Library

    Kalai Mathee; Giri Narasimhan; Camilo Valdes; Xiaoyun Qiu; Jody M. Matewish; Michael Koehrsen; Antonis Rokas; Chandri N. Yandava; Reinhard Engels; Erliang Zeng; Raquel Olavarietta; Melissa Doud; Roger S. Smith; Philip Montgomery; Jared R. White; Paul A. Godfrey; Chinnappa Kodira; Bruce Birren; James E. Galagan; Stephen Lory

    2008-01-01

    One of the hallmarks of the Gram-negative bacterium Pseudomonas aeruginosa is its ability to thrive in diverse environments that includes humans with a variety of debilitating diseases or immune deficiencies...

  19. Pseudomonas aeruginosa: resistance to the max

    National Research Council Canada - National Science Library

    Poole, Keith

    2011-01-01

    Pseudomonas aeruginosa is intrinsically resistant to a variety of antimicrobials and can develop resistance during anti-pseudomonal chemotherapy both of which compromise treatment of infections caused by this organism...

  20. Pseudomonas Lipopeptide Biosurfactants

    DEFF Research Database (Denmark)

    Bonnichsen, Lise

    of the Pseudomonas lipopeptides belonging to different structural groups on important biodegradation parameters, mainly; solubilization and emulsification of hydrophobic pollutants (alkanes and PAHs) and increase of cell surface hydrophobicity of bacterial degraders. Ultimately, it was tested if these parameters led......Pseudomonas lipopetide biosurfactants are amphiphilic molecules with a broad range of natural functions. Due to their surface active properties, it has been suggested that Pseudomonas lipopetides potentially play a role in biodegradation of hydrophobic compounds and have essential functions...... in biofilm formation, however, detailed studies of these roles have not yet been carried out. The overall aim of this PhD project was therefore to elucidate in more depth the roles played by Pseudomonas lipopetides in pollutant biodegradation and biofilm formation. This study investigated the effect...

  1. Pseudomonas Lipopeptide Biosurfactants

    DEFF Research Database (Denmark)

    Bonnichsen, Lise

    lipopetide biosurfactants in pollutant biodegradation and natural roles in biofilm formation. The work presented is a combination of environmental microbiology and exploiting genetic manipulation of pure cultures to achieve insightinto the effects and mechanisms of lipopeptides on microbial processes......Pseudomonas lipopetide biosurfactants are amphiphilic molecules with a broad range of natural functions. Due to their surface active properties, it has been suggested that Pseudomonas lipopetides potentially play a role in biodegradation of hydrophobic compounds and have essential functions...

  2. Development of metabolite profiling and metabolomics tools for Pseudomonas taiwanensis VLB120

    DEFF Research Database (Denmark)

    Wordofa, Gossa Garedew; Kristensen, Mette; Schneider, Konstantin

    Pseudomonas sp. VLB120 is a biofilm-forming Gram negative aerobic strain that isolated from soil at Institute of Microbiology, University of Stuttgart, Germany. The strain has an ability to survive and even able to grow in the presence of toxic solvents including octanol, toluene, and styrene...... are investigating the metabolic state of P.VLB120 strain and testing the suitability of commonly used metabolomics tools for this strain, as many of the tools were designed for specific classes of metabolites or microorganisms....

  3. Cyanase-mediated utilization of cyanate in Pseudomonas fluorescens NCIB 11764.

    Science.gov (United States)

    Kunz, D A; Nagappan, O

    1989-01-01

    Pseudomonas fluorescens NCIB 11764 was capable of utilizing cyanate (OCN-) as a sole nitrogen source for growth. Crude cell extracts from cells grown on cyanate, but not on ammonium sulfate, were induced for an enzyme catalyzing cyanate conversion to ammonia. Enzymatic activity was shown to be bicarbonate dependent and specific for cyanate as a substrate, suggesting that cyanate utilization in this organism is facilitated by an enzyme resembling cyanase (cyanate amidohydrolase; EC 3.5.5.3), as described previously in Escherichia coli and Flavobacterium sp.

  4. Sigma factors in Pseudomonas aeruginosa.

    Science.gov (United States)

    Potvin, Eric; Sanschagrin, François; Levesque, Roger C

    2008-01-01

    In Pseudomonas aeruginosa, as in most bacterial species, the expression of genes is tightly controlled by a repertoire of transcriptional regulators, particularly the so-called sigma (sigma) factors. The basic understanding of these proteins in bacteria has initially been described in Escherichia coli where seven sigma factors are involved in core RNA polymerase interactions and promoter recognition. Now, 7 years have passed since the completion of the first genome sequence of the opportunistic pathogen P. aeruginosa. Information from the genome of P. aeruginosa PAO1 identified 550 transcriptional regulators and 24 putative sigma factors. Of the 24 sigma, 19 were of extracytoplasmic function (ECF). Here, basic knowledge of sigma and ECF proteins was reviewed with particular emphasis on their role in P. aeruginosa global gene regulation. Summarized data are obtained from in silico analysis of P. aeruginosasigma and ECF including rpoD (sigma(70)), RpoH (sigma(32)), RpoF (FliA or sigma(28)), RpoS (sigma(S) or sigma(38)), RpoN (NtrA, sigma(54) or sigma(N)), ECF including AlgU (RpoE or sigma(22)), PvdS, SigX and a collection of uncharacterized sigma ECF, some of which are implicated in iron transport. Coupled to systems biology, identification and functional genomics analysis of P. aeruginosasigma and ECF are expected to provide new means to prevent infection, new targets for antimicrobial therapy, as well as new insights into the infection process.

  5. Main: SP8BFIBSP8AIB [PLACE

    Lifescience Database Archive (English)

    Full Text Available SP8BFIBSP8AIB S000183 16-Feb-2001 (last modified) seki One of SPBF binding site (SP...o (I.b.); SP8BF recognizes both SP8a and SP8b sequences; See also SP8BFIBSP8BIB (S000184); SP8BF activity is

  6. Main: SP8BFIBSP8BIB [PLACE

    Lifescience Database Archive (English)

    Full Text Available SP8BFIBSP8BIB S000184 16-Feb-2001 (last modified) seki One of SPBF binding site (SP...; SP8BF recognizes both SP8a and SP8b sequences; See also SP8BFIBSP8AIB (S000183); SP8BF activity is also fo

  7. Genotypische diversiteit en rhizosfeerkolonisatie van DAPG-producerende Pseudomonas spp.

    NARCIS (Netherlands)

    Bergsma-Vlami, M.

    2009-01-01

    Het antibioticum 2,4-diacetylphloroglucinol (DAPG) speelt een belangrijke rol in biologische bestrijding van verschillende plantenpathogenen door fluorescerende Pseudomonas-soorten. DAPG-producerende Pseudomonas-stammen zijn effectief in biologische bestrijding, maar hun saprofytisch vermogen is vaa

  8. Pseudomonas aeruginosa biofilms in disease.

    Science.gov (United States)

    Mulcahy, Lawrence R; Isabella, Vincent M; Lewis, Kim

    2014-07-01

    Pseudomonas aeruginosa is a ubiquitous organism that is the focus of intense research because of its prominent role in disease. Due to its relatively large genome and flexible metabolic capabilities, this organism exploits numerous environmental niches. It is an opportunistic pathogen that sets upon the human host when the normal immune defenses are disabled. Its deadliness is most apparent in cystic fibrosis patients, but it also is a major problem in burn wounds, chronic wounds, chronic obstructive pulmonary disorder, surface growth on implanted biomaterials, and within hospital surface and water supplies, where it poses a host of threats to vulnerable patients (Peleg and Hooper, N Engl J Med 362:1804-1813, 2010; Breathnach et al., J Hosp Infect 82:19-24, 2012). Once established in the patient, P. aeruginosa can be especially difficult to treat. The genome encodes a host of resistance genes, including multidrug efflux pumps (Poole, J Mol Microbiol Biotechnol 3:255-264, 2001) and enzymes conferring resistance to beta-lactam and aminoglycoside antibotics (Vahdani et al., Annal Burns Fire Disast 25:78-81, 2012), making therapy against this gram-negative pathogen particularly challenging due to the lack of novel antimicrobial therapeutics (Lewis, Nature 485: 439-440, 2012). This challenge is compounded by the ability of P. aeruginosa to grow in a biofilm, which may enhance its ability to cause infections by protecting bacteria from host defenses and chemotherapy. Here, we review recent studies of P. aeruginosa biofilms with a focus on how this unique mode of growth contributes to its ability to cause recalcitrant infections.

  9. Efficacy of selected Pseudomonas strains for biocontrol of Rhizoctonia solani in potato

    Directory of Open Access Journals (Sweden)

    Moncef MRABET

    2014-01-01

    Full Text Available Thirty seven bacterial isolates from faba bean (Vicia faba L. root-nodules were screened for their antagonistic activity against eight Rhizoctonia solani strains isolated from infected potato (Solanum tuberosum L. tubers. Two bacterial strains (designated as Kl.Fb14 and S8.Fb11 gave 50% in vitro inhibition of R. solani mycelial growth. 16S rDNA sequence analysis indicated that strain Kl.Fb14 exhibited 99.5% identity with Pseudomonas moraviensis, and that S8.Fb11 exhibited 99.8% identity with Pseudomonas reinekei. Greenhouse trials in soil showed that strain S8.Fb11 reduced the percentage of sclerotia on potato tubers and amounts of tuber infection for the potato cultivars Spunta and Nicola. In a field trial conducted in South Tunisia, infection with R. solani reduced potato yield by approximately 40% for ‘Spunta’ and 17% for ‘Nicola’; about 20% of the total tuber production was severely infected. However, when potato tubers were treated with strain S8.Fb11 prior to sowing, disease incidence was reduced to 6% of total production with low infection levels; potato yield was enhanced by about 6 kg per 10 m row in comparison to R. solani infected plants. The second selected Pseudomonas sp. (strain Kl.Fb14 did not affect either the levels of sclerotia on tubers or potato yield.

  10. Vaccines for preventing infection with Pseudomonas aeruginosa in cystic fibrosis

    DEFF Research Database (Denmark)

    Johansen, Helle Krogh; Gøtzsche, Peter C

    2013-01-01

    Chronic pulmonary infection in cystic fibrosis results in progressive lung damage. Once colonisation of the lungs with Pseudomonas aeruginosa occurs, it is almost impossible to eradicate. Vaccines, aimed at reducing infection with Pseudomonas aeruginosa, have been developed.......Chronic pulmonary infection in cystic fibrosis results in progressive lung damage. Once colonisation of the lungs with Pseudomonas aeruginosa occurs, it is almost impossible to eradicate. Vaccines, aimed at reducing infection with Pseudomonas aeruginosa, have been developed....

  11. Diversity of small RNAs expressed in Pseudomonas species

    DEFF Research Database (Denmark)

    Gomez-Lozano, Mara; Marvig, Rasmus Lykke; Molina-Santiago, Carlos;

    2015-01-01

    RNA sequencing (RNA-seq) has revealed several hundreds of previously undetected small RNAs (sRNAs) in all bacterial species investigated, including strains of Pseudomonas aeruginosa, Pseudomonas putida and Pseudomonas syringae. Nonetheless, only little is known about the extent of conservation of...

  12. 21 CFR 866.3415 - Pseudomonas spp. serological reagents.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Pseudomonas spp. serological reagents. 866.3415... (CONTINUED) MEDICAL DEVICES IMMUNOLOGY AND MICROBIOLOGY DEVICES Serological Reagents § 866.3415 Pseudomonas spp. serological reagents. (a) Identification. Pseudomonas spp. serological reagents are devices...

  13. Parasitismo por Giardia sp. e Cryptosporidium sp. em Coendou villosus Parasitism by Giardia sp. and Cryptosporidium sp. in Coendou villosus

    Directory of Open Access Journals (Sweden)

    João Fabio Soares

    2008-04-01

    Full Text Available O objetivo deste trabalho foi verificar o possível parasitismo por Giardia sp. e Cryptosporidium sp. em amostras de fezes de ouriço-cacheiro (Coendou villosus. As amostras foram analisadas pelo método de centrífugo-flutuação com sulfato de zinco e apresentaram elevada infecção por cistos de Giardia sp. e por oocistos de Cryptosporidium sp., embora os animais não apresentassem sinal clínico decorrente disso.This research was aimed at verifing the possible parasitism by Giardia sp. and Cryptosporidium sp. in porcupine (Coendou villosus faeces samples. Samples were analyzed by the centrifugal-flotation method with zinc sulphate and showed high infection by cysts of Giardia sp. and by oocysts of Cryptosporidium sp., although the animals did not show any associated clinical sign.

  14. A novel enterocin T1 with anti-Pseudomonas activity produced by Enterococcus faecium T1 from Chinese Tibet cheese.

    Science.gov (United States)

    Liu, Hui; Zhang, Lanwei; Yi, Huaxi; Han, Xue; Gao, Wei; Chi, Chunliang; Song, Wei; Li, Haiying; Liu, Chunguang

    2016-02-01

    An enterocin-producing Enterococcus faecium T1 was isolated from Chinese Tibet cheese. The enterocin was purified by SP-Sepharose and reversed phase HPLC. It was identified as unique from other reported bacteriocins based on molecular weight (4629 Da) and amino acid compositions; therefore it was subsequently named enterocin T1. Enterocin T1 was stable at 80-100 °C and over a wide pH range, pH 3.0-10.0. Protease sensitivity was observed to trypsin, pepsin, papain, proteinase K, and pronase E. Importantly, enterocin T1 was observed to inhibit the growth of numerous Gram-negative and Gram-positive bacteria including Pseudomonas putida, Pseudomonas aeruginosa, Pseudomonas fluorescens, Escherichia coli, Salmonella typhimurium, Shigella flexneri, Shigella sonnei, Staphylococcus aureus, Listeria monocytogenes. Take together, these results suggest that enterocin T1 is a novel bacteriocin with the potential to be used as a bio-preservative to control Pseudomonas spp. in food.

  15. Isolation of copper oxide (CuO) nanoparticles resistant Pseudomonas strains from soil and investigation on possible mechanism for resistance.

    Science.gov (United States)

    Soltani Nezhad, Shahla; Rabbani Khorasgani, Mohammad; Emtiazi, Giti; Yaghoobi, Mohammad Mehdi; Shakeri, Shahryar

    2014-03-01

    The present study deals with isolation and characterization of copper oxide nanoparticles resistant Pseudomonas strains that were isolated from the soil collected from mining and refining sites of Sarcheshmeh copper mine in the Kerman Province of Iran. The three isolates were selected based on high level of copper oxide nanoparticles (CuO NPs) resistance. The isolates were authentically identified as Pseudomonas fluorescens CuO-1, Pseudomonas fluorescens CuO-2 and Pseudomonas sp. CuO-3 by morphological, biochemical and 16S rDNA gene sequencing analysis. The growth pattern of these isolates with all the studied CuO NPs concentrations was similar to that of control (without CuO NPs) indicating that CuO NPs would not affect the growth of isolated strains. A reduction in the amount of exopolysaccharides was observed after CuO NPs-P. fluorescens CuO-1 culture supernatant interaction. The Fourier transform infrared spectroscopy (FT-IR) peaks for the exopolysaccharides extracted from the bacterial culture supernatant and the interacted CuO NPs were almost similar. The exopolysaccharide capping of the CuO NPs was confirmed by FT-IR and X-ray diffraction analysis. The study of bacterial exopolysaccharides capped CuO NPs with E. coli PTCC 1338 and S. aureus PTCC 1113 showed less toxicity compared to uncoated CuO NPs. Our study suggests that the capping of nanoparticles by bacterially produced exopolysaccharides serve as the probable mechanism of tolerance.

  16. Pseudomonas aeruginosa elastase provides an escape from phagocytosis by degrading the pulmonary surfactant protein-A.

    Directory of Open Access Journals (Sweden)

    Zhizhou Kuang

    Full Text Available Pseudomonas aeruginosa is an opportunistic pathogen that causes both acute pneumonitis in immunocompromised patients and chronic lung infections in individuals with cystic fibrosis and other bronchiectasis. Over 75% of clinical isolates of P. aeruginosa secrete elastase B (LasB, an elastolytic metalloproteinase that is encoded by the lasB gene. Previously, in vitro studies have demonstrated that LasB degrades a number of components in both the innate and adaptive immune systems. These include surfactant proteins, antibacterial peptides, cytokines, chemokines and immunoglobulins. However, the contribution of LasB to lung infection by P. aeruginosa and to inactivation of pulmonary innate immunity in vivo needs more clarification. In this study, we examined the mechanisms underlying enhanced clearance of the ΔlasB mutant in mouse lungs. The ΔlasB mutant was attenuated in virulence when compared to the wild-type strain PAO1 during lung infection in SP-A+/+ mice. However, the ΔlasB mutant was as virulent as PAO1 in the lungs of SP-A⁻/⁻ mice. Detailed analysis showed that the ΔlasB mutant was more susceptible to SP-A-mediated opsonization but not membrane permeabilization. In vitro and in vivo phagocytosis experiments revealed that SP-A augmented the phagocytosis of ΔlasB mutant bacteria more efficiently than the isogenic wild-type PAO1. The ΔlasB mutant was found to have a severely reduced ability to degrade SP-A, consequently making it unable to evade opsonization by the collectin during phagocytosis. These results suggest that P. aeruginosa LasB protects against SP-A-mediated opsonization by degrading the collectin.

  17. Induced systemic resistance by fluorescent Pseudomonas spp.

    NARCIS (Netherlands)

    Bakker, P.A.H.M.; Pieterse, C.M.J.; Loon, L.C. van

    2007-01-01

    Fluorescent Pseudomonas spp. have been studied for decades for their plant growth-promoting effects through effective suppression of soilborne plant diseases. The modes of action that play a role in disease suppression by these bacteria include siderophore-mediated competition for iron, antibiosis,

  18. strains of pseudomonas aeruginosa and bacillus cereus

    African Journals Online (AJOL)

    DR. AMINU

    sense mutation with beneficial effects of increased petroleum degradation. The amino acids requirement for growth could thus be used as a genetic marker for organisms that are subjected to ... Fluorescence under UV light: The inoculated plates .... acid treated Pseudomonas aeruginosa; + = growth; - = all other amino.

  19. Targeting quorum sensing in Pseudomonas aeruginosa biofilms

    DEFF Research Database (Denmark)

    Jakobsen, Tim Holm; Bjarnsholt, Thomas; Jensen, Peter Østrup

    2013-01-01

    alternative antibacterial strategies. Here, we review state of the art research of quorum sensing inhibitors against the opportunistic human pathogen Pseudomonas aeruginosa, which is found in a number of biofilm-associated infections and identified as the predominant organism infecting the lungs of cystic...

  20. Biodegradation of chlorpyrifos by bacterial genus Pseudomonas.

    Science.gov (United States)

    Gilani, Razia Alam; Rafique, Mazhar; Rehman, Abdul; Munis, Muhammad Farooq Hussain; Rehman, Shafiq Ur; Chaudhary, Hassan Javed

    2016-02-01

    Chlorpyrifos is an organophosphorus pesticide commonly used in agriculture. It is noxious to a variety of organisms that include living soil biota along with beneficial arthropods, fish, birds, humans, animals, and plants. Exposure to chlorpyrifos may cause detrimental effects as delayed seedling emergence, fruit deformities, and abnormal cell division. Contamination of chlorpyrifos has been found about 24 km from the site of its application. There are many physico-chemical and biological approaches to remove organophosphorus pesticides from the ecosystem, among them most promising is biodegradation. The 3,5,6-trichloro-2-pyridinol (TCP) and diethylthiophosphate (DETP) as primary products are made when chlorpyrifos is degraded by soil microorganisms which further break into nontoxic metabolites as CO(2), H(2)O, and NH(3). Pseudomonas is a diversified genus possessing a series of catabolic pathways and enzymes involved in pesticide degradation. Pseudomonas putida MAS-1 is reported to be more efficient in chlorpyrifos degradation by a rate of 90% in 24 h among Pseudomonas genus. The current review analyzed the comparative potential of bacterial species in Pseudomonas genus for degradation of chlorpyrifos thus, expressing an ecofriendly approach for the treatment of environmental contaminants like pesticides.

  1. New Pseudomonas spp. Are Pathogenic to Citrus.

    Directory of Open Access Journals (Sweden)

    Farid Beiki

    Full Text Available Five putative novel Pseudomonas species shown to be pathogenic to citrus have been characterized in a screening of 126 Pseudomonas strains isolated from diseased citrus leaves and stems in northern Iran. The 126 strains were studied using a polyphasic approach that included phenotypic characterizations and phylogenetic multilocus sequence analysis. The pathogenicity of these strains against 3 cultivars of citrus is demonstrated in greenhouse and field studies. The strains were initially grouped phenotypically and by their partial rpoD gene sequences into 11 coherent groups in the Pseudomonas fluorescens phylogenetic lineage. Fifty-three strains that are representatives of the 11 groups were selected and analyzed by partial sequencing of their 16S rRNA and gyrB genes. The individual and concatenated partial sequences of the three genes were used to construct the corresponding phylogenetic trees. The majority of the strains were identified at the species level: P. lurida (5 strains, P. monteilii (2 strains, P. moraviensis (1 strain, P. orientalis (16 strains, P. simiae (7 strains, P. syringae (46 strains, distributed phylogenetically in at least 5 pathovars, and P. viridiflava (2 strains. This is the first report of pathogenicity on citrus of P. orientalis, P. simiae, P. lurida, P. moraviensis and P. monteilii strains. The remaining 47 strains that could not be identified at the species level are considered representatives of at least 5 putative novel Pseudomonas species that are not yet described.

  2. Isolation and characterization of arsenite oxidizing Pseudomonas ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-03-08

    Mar 8, 2010 ... African Journal of Biotechnology Vol. 9(10), pp. 1493-1498, 8 .... Industrial wastewater samples were collected in screw capped sterilized bottles from .... similarity), Pseudomonas alcaliphila strain Q1-3 EU. 144361.1 (gi/ ...

  3. Plant growth promotion by Pseudomonas fluorescens

    NARCIS (Netherlands)

    Cheng, X.

    2016-01-01

    Pseudomonas fluorescens is a Gram-negative rod shaped bacterium that has a versatile metabolism and is widely spread in soil and water. P. fluorescens strain SBW25 (Pf.SBW25) is a well-known model strain to study bacterial evolution, plant colonization and biocontrol of plant diseases. It produces t

  4. Extracytoplasmic function sigma factors in Pseudomonas syringae

    DEFF Research Database (Denmark)

    Kiil, Kristoffer; Oguiza, J.A.; Ussery, D.W.

    2005-01-01

    Genome analyses of the plant pathogens Pseudomonas syringae pv. tomato DC3000, pv. syringae B728a and pv. phaseolicola 1448A reveal fewer extracytoplasmic function (ECF) sigma factors than in related Pseudomonads with different lifestyles. We highlight the presence of a P. syringae-specific ECF...

  5. Pseudomonas sepsis with Noma: an association?

    Science.gov (United States)

    Vaidyanathan, S; Tullu, M S; Lahiri, K R; Deshmukh, C T

    2005-08-01

    We report here a 2.5-year-old male child with community-acquired Pseudomonal sepsis showing the characteristic lesions of ecthyma gangrenosum. The child had development of gangrenous changes of the nose and face - the 'cancrum oris' or 'Noma'. We highlight the possible association of Pseudomonas sepsis and Noma, with malnutrition playing a central role in causing both the diseases.

  6. New Pseudomonas spp. Are Pathogenic to Citrus.

    Science.gov (United States)

    Beiki, Farid; Busquets, Antonio; Gomila, Margarita; Rahimian, Heshmat; Lalucat, Jorge; García-Valdés, Elena

    2016-01-01

    Five putative novel Pseudomonas species shown to be pathogenic to citrus have been characterized in a screening of 126 Pseudomonas strains isolated from diseased citrus leaves and stems in northern Iran. The 126 strains were studied using a polyphasic approach that included phenotypic characterizations and phylogenetic multilocus sequence analysis. The pathogenicity of these strains against 3 cultivars of citrus is demonstrated in greenhouse and field studies. The strains were initially grouped phenotypically and by their partial rpoD gene sequences into 11 coherent groups in the Pseudomonas fluorescens phylogenetic lineage. Fifty-three strains that are representatives of the 11 groups were selected and analyzed by partial sequencing of their 16S rRNA and gyrB genes. The individual and concatenated partial sequences of the three genes were used to construct the corresponding phylogenetic trees. The majority of the strains were identified at the species level: P. lurida (5 strains), P. monteilii (2 strains), P. moraviensis (1 strain), P. orientalis (16 strains), P. simiae (7 strains), P. syringae (46 strains, distributed phylogenetically in at least 5 pathovars), and P. viridiflava (2 strains). This is the first report of pathogenicity on citrus of P. orientalis, P. simiae, P. lurida, P. moraviensis and P. monteilii strains. The remaining 47 strains that could not be identified at the species level are considered representatives of at least 5 putative novel Pseudomonas species that are not yet described.

  7. High pressure inactivation of Pseudomonas in black truffle - comparison with Pseudomonas fluorescens in tryptone soya broth

    Science.gov (United States)

    Ballestra, Patricia; Verret, Catherine; Cruz, Christian; Largeteau, Alain; Demazeau, Gerard; El Moueffak, Abdelhamid

    2010-03-01

    Pseudomonas is one of the most common genera in black Perigord truffle. Its inactivation by high pressure (100-500 MPa/10 min) applied on truffles at sub-zero or low temperatures was studied and compared with those of Pseudomonas fluorescens in tryptone soya broth. Pressurization of truffles at 300 MPa/4 °C reduced the bacterial count of Pseudomonas by 5.3 log cycles. Higher pressures of 400 or 500 MPa, at 4 °C or 20 °C, allowed us to slightly increase the level of destruction to the value of ca. 6.5 log cycles but did not permit us to completely inactivate Pseudomonas. The results showed a residual charge of about 10 CFU/g. Pressure-shift freezing of truffles, which consists in applying a pressure of 200 MPa/-18 °C for 10 min and then quickly releasing this pressure to induce freezing, reduced the population of Pseudomonas by 3.3 log cycles. The level of inactivation was higher than those obtained with conventional freezing. Endogenous Pseudomonas in truffle was shown to be more resistant to high pressure treatments than P. fluorescens used for inoculation of broths.

  8. Identification of anthranilate and benzoate metabolic operons of Pseudomonas fluorescens and functional characterization of their promoter regions

    Directory of Open Access Journals (Sweden)

    Lee Vincent D

    2006-01-01

    Full Text Available Abstract Background In an effort to identify alternate recombinant gene expression systems in Pseudomonas fluorescens, we identified genes encoding two native metabolic pathways that were inducible with inexpensive compounds: the anthranilate operon (antABC and the benzoate operon (benABCD. Results The antABC and benABCD operons were identified by homology to the Acinetobacter sp. anthranilate operon and Pseudomonas putida benzoate operon, and were confirmed to be regulated by anthranilate or benzoate, respectively. Fusions of the putative promoter regions to the E. coli lacZ gene were constructed to confirm inducible gene expression. Each operon was found to be controlled by an AraC family transcriptional activator, located immediately upstream of the first structural gene in each respective operon (antR or benR. Conclusion We have found the anthranilate and benzoate promoters to be useful for tightly controlling recombinant gene expression at both small (

  9. Antimicrobial activities of rhizobacterial strains of Pseudomonas and Bacillus strains isolated from rhizosphere soil of carnation (Dianthus caryophyllus cv. Sunrise).

    Science.gov (United States)

    Sharma, Sapna; Kaur, Mohinder

    2010-06-01

    Under the present study, an attempt was made to characterize rhizobacteria i.e. Pseudomonas and Bacillus species isolated from rhizosphere of carnation to evaluate their growth promoting effect on carnation so as to select and develop more efficient indigenous plant growth promoting and disease suppressing bioagents of specific soil type and specific plant type. Maximum strains of Pseudomonas and Bacillus sp. showed significant antimicrobial activities against most of the microorganisms tested. On the basis of in vitro antagonistic activities, the best strains were selected and used in field trial to study the influence of these strains on the growth of carnation. Results have shown marked effect on growth parameters and disease incidence has also been reduced significantly.

  10. Tsukamurella inchonensis sp. nov.

    Science.gov (United States)

    Yassin, A F; Rainey, F A; Brzezinka, H; Burghardt, J; Lee, H J; Schaal, K P

    1995-07-01

    Chemotaxonomic and genomic 16S ribosomal DNA sequence analyses of two isolates obtained from two different clinical materials clearly delineated a new species of the genus Tsukamurella. This new species can be identified by its 16S ribosomal DNA similarity values, as well as its physiological characteristics. The name Tsukamurella inchonensis sp. nov. is proposed for these isolates, which are represented by strain IMMIB D-771T (= DSM 44067T) (T = type strain). This strain exhibits only 45% DNA relatedness to Tsukamurella paurometabola.

  11. Biological control of Sclerotinia sclerotiorum (Lib.) de Bary, the causal agent of white mold, by Pseudomonas species on canola petals.

    Science.gov (United States)

    Behnam, S; Ahmadzadeh, M; Sharifi Tehrani, A; Hedjaroude, Gh A; Farzaneh, M

    2007-01-01

    Sclerotinia sclerotiorum is an important pathogen on canola. Due to the public concern over pesticide use, alternative methods of disease control, such as biological control, should be considered. Several bacterial strains were isolated from canola and soja plants. Inhibition of S. sclerotiorum by bacterial strains in vitro was assayed on PDA medium in dual culture test. Eight Pseudomonas sp. strains (PB-3, PB-4, PB-5, PB-6, PB-7, PB-8, PB-10 and PB-11) caused inhibition zone against 5. sclerotiorum hyphal growth. The biocontrol potential of the bacteria was tested in a plant assay. Disease suppression was investigated using a petal inoculation technique. Canola petals were pretreated with bacteria, and then inoculated with 5. sclerotiorum ascospores 24 h later. Greenhouse experiment showed that application of Pseudomonas sp. strains (1 x 10(8) cfu ml(-1)) effectively suppressed S. sclerotiorum (1 x 10(5) ascospores ml(-1)) on petals and all of them achieved significant (P<0.01) disease suppression. Fourteen days after inoculation, strain PB-3 had 88/7% disease control and strain PB-4 had 69/9% disease control. Result from all studies indicates PB-3 to be effective biocontrol against S. sclerotiorum of canola. PB-3, PB-4, PB-7, PB-8, PB-10 and PB-11 were identified as Pseudomonas fluorescens biovar III. PB-5 and PB-6 was identified as Pseudomonas fluorescens biovar II. Strains PB-3, PB-4, PB-6, PB-10 and PB-11 produced protease and HCN. Strain PB-5 produce protease; no HCN.

  12. The role of the antimicrobial compound 2,4-diacetylphloroglucinol in the impact of biocontrol Pseudomonas fluorescens F113 on Azospirillum brasilense phytostimulators.

    Science.gov (United States)

    Couillerot, Olivier; Combes-Meynet, Emeline; Pothier, Joël F; Bellvert, Floriant; Challita, Elita; Poirier, Marie-Andrée; Rohr, René; Comte, Gilles; Moënne-Loccoz, Yvan; Prigent-Combaret, Claire

    2011-06-01

    Pseudomonads producing the antimicrobial metabolite 2,4-diacetylphloroglucinol (Phl) can control soil-borne phytopathogens, but their impact on other plant-beneficial bacteria remains poorly documented. Here, the effects of synthetic Phl and Phl(+) Pseudomonas fluorescens F113 on Azospirillum brasilense phytostimulators were investigated. Most A. brasilense strains were moderately sensitive to Phl. In vitro, Phl induced accumulation of carotenoids and poly-β-hydroxybutyrate-like granules, cytoplasmic membrane damage and growth inhibition in A. brasilense Cd. Experiments with P. fluorescens F113 and a Phl(-) mutant indicated that Phl production ability contributed to in vitro growth inhibition of A. brasilense Cd and Sp245. Under gnotobiotic conditions, each of the three strains, P. fluorescens F113 and A. brasilense Cd and Sp245, stimulated wheat growth. Co-inoculation of A. brasilense Sp245 and Pseudomonas resulted in the same level of phytostimulation as in single inoculations, whereas it abolished phytostimulation when A. brasilense Cd was used. Pseudomonas Phl production ability resulted in lower Azospirillum cell numbers per root system (based on colony counts) and restricted microscale root colonization of neighbouring Azospirillum cells (based on confocal microscopy), regardless of the A. brasilense strain used. Therefore, this work establishes that Phl(+) pseudomonads have the potential to interfere with A. brasilense phytostimulators on roots and with their plant growth promotion capacity.

  13. Isolation and identification of the acetonitrile-degrading Pseudomonas from the Ab-anbar-e Ganjali Khan in Kerman

    Directory of Open Access Journals (Sweden)

    Narjes Ramezani–pour

    2016-06-01

    Full Text Available Introduction: Nitriles are toxic and hazardous compounds for all organisms which are produced enormously by human being and cause environment pollution. Biodegradation is the best method for Nitrile elimination in sewage. The aim of this study was isolation and identification of native bacteria Acetonitrile-degrading from the sewage of the city of Kerman. Materials and methods: The enrichment and screening of Acetonitrile degrading bacteria was performed in a specific medium containing 1 % Acetonitrile as sole carbon and nitrogen source. Enzyme activity and ammonium production was determined in growth medium using a modification of the phenol/hypochlorite method. Identification of the isolates was undertaken using microbial - biochemical and molecular tests. The optimization of enzyme production was examined. The amount of nitrile and acid were also determined by gas chromatography. Results: Among three isolated nitrile hydrolyzing producing species (FA3, FA8 and AB19, FA8 isolate showed maximum enzyme productivity. The results of characteristic tests showed that these bacteria belonged to the Pseudomonas sp. Moreover, 16S rRNA sequencing and phylogenetic analyses exhibited that FA11, FA8 and AB19 strains were similar to Pseudomonas Otitidis and Pseudomonas geniculate with 99, 100% homology, respectively. Results of medium optimization of Pseudomonas FA8 strain showed that glucose (10 gL-1 and yeast extract (5 gL-1 in neutral medium strongly supported enzyme production. Gas chromatography results showed that FA8 produced 58% acetic acid at 48 h of incubation. Discussion and conclusion: The results demonstrated that Pseudomonas FA8 isolated bacterium is a suitable candidate for degradation of Acetonitrile. This bacterium could be used for treatment of industrial wastewater and sites that contaminated with Acetonitrile.

  14. Control of Branchionus sp. and Amoeba sp. in cultures of Arthrospira sp. Control de Branchionus sp. y Amoeba sp. en cultivos de Arthrospira sp.

    Directory of Open Access Journals (Sweden)

    Carlos Méndez

    2012-09-01

    Full Text Available Cultivation of cyanobacterium Arthrospira sp. has been developed in many countries for the production of proteins, pigments and other compounds. Outdoor mass cultures are often affected by biological contamination, drastically reducing productivity as far as bringing death. This study evaluates the control of Branchionus sp. and Amoeba sp. with two chemical compounds: urea (U and ammonium bicarbonate (AB, in laboratory conditions and outdoor mass culture of Arthrospira sp. The lethal concentration 100 (LC100 at 24 h for Branchionus sp. and Amoeba sp. determined was of 60-80 mg L-1 (U and 100-150 mg L-1 (AB. The average effective inhibition concentration for 50% of the population (IC50 in Arthrospira sp., after 72 h, was 80 mg L-1 (U and 150 mg L-1 (AB. The application of doses of 60 mg L-1 (U or 100 mg L-1 (AB in the outdoor mass culture of this contaminated microalga, completely inhibited grazing and did not affect the growth of Arthrospira sp. but rather promoted rapid recovery of algal density at levels prior to infestation. These compounds provided an economical and effective control of predators in cultures of Arthrospira sp.El cultivo de la cianobacteria Arthrospira sp. ha sido desarrollado en muchos países para la obtención de proteínas, pigmentos y otros compuestos. Cultivo que a nivel industrial se ve afectado frecuentemente por contaminación biológica, reduciendo drásticamente la productividad hasta causar la muerte. Este estudio evalúa el control de Branchionus sp. y de Amoeba sp. con dos compuestos químicos, la urea (U y bicarbonato de amonio (AB en cultivos de Arthrospira sp. La concentración letal 100 (LC100 determinada a las 24 h para Branchionus sp. y Amoeba sp. fue de 60-80 mg L-1 (U y 100-150 mg L-1 (AB. La concentración media de inhibición efectiva, después de 72 h, para el 50% de la población (IC50 en Arthrospira fue de 80 mg L-1 (U y 150 mg L-1 (AB. La aplicación de dosis de 60 mg L-1 (U ó 100 mg L-1 (AB en

  15. Aspergillus triggers phenazine production in Pseudomonas aeruginosa

    DEFF Research Database (Denmark)

    Jensen, Britt Guillaume; Jelsbak, Lars; Søndergaard, Ib

    Objectives: Pseudomonas aeruginosa is an opportunistic human pathogen, commonly infecting cystic fibrosis (CF) patients. Aspergilli, especially Aspergillus fumigatus, are also frequently isolated from CF patients. Our aim was to examine the possible interaction between P. aeruginosa and different...... Aspergillus species. Methods: A suspension of fungal spores was streaked onto WATM agar plates. After 24 hours incubation at 37 °C, a P. aeruginosa overnight culture was streaked out perpendicular to the fungal streak. The plates were incubated at 37 °C for five days, examined and plugs were extracted...... in the contact area of A. niger, A. flavus, A. oryzae, but not A. fumigatus. In addition, other metabolites with UV chromophores similar to the phenazines were only found in the contact zone between Aspergillus and Pseudomonas. No change in secondary metabolite profiles were seen for the Aspergilli, when...

  16. Use of the anti-Prelog stereospecific alcohol dehydrogenase from Leifsonia and Pseudomonas for producing chiral alcohols.

    Science.gov (United States)

    Itoh, Nobuya

    2014-05-01

    The asymmetric reduction of ketones is one of the most promising processes for producing chiral alcohols. However, dehydrogenases or reductases that can catalyze the reduction of ketones to give anti-Prelog chiral alcohols have been limited to some NADP(+)/NADPH-dependent enzymes. Recently, we reported a novel NAD(+)/NADH-dependent alcohol dehydrogenase (ADH) from Leifsonia sp. and Pseudomonas ADH homologs from soil metagenomes. Moreover, we have established an efficient hydrogen-transfer bioreduction process with 2-propanol as a hydrogen donor using Leifsonia ADH. This review focuses on the recent development of novel ADHs for producing industrially useful anti-Prelog chiral alcohols from various ketones.

  17. Antibacterial activity of the Antarctic bacterium Janthinobacterium sp. SMN 33.6 against multi-resistant Gram-negative bacteria

    Directory of Open Access Journals (Sweden)

    Geraldine Asencio

    2014-01-01

    Conclusions: The ethanolic extract of Janthinobacterium sp. SMN 33.6 possesses antibacterial activity against a chromosomal AmpC beta-lactamase-producing strain of Serratia marcescens, an extended-spectrum beta-lactamase-producing Escherichia coli and also against carbapenemase-producing strains of Acinetobacter baumannii and Pseudomonas aeruginosa. This becomes a potential and interesting biotechnological tool for the control of bacteria with multi-resistance to commonly used antibiotics.

  18. Tsukamurella pulmonis sp. nov.

    Science.gov (United States)

    Yassin, A F; Rainey, F A; Brzezinka, H; Burghardt, J; Rifai, M; Seifert, P; Feldmann, K; Schaal, K P

    1996-04-01

    Chemotaxonomic and 16S ribosomal DNA sequence analyses of an isolate from the sputum of a patient with a mycobacterial lung infection clearly delineated a new species of the genus Tsukamurella. This new species can be defined on the basis of genotypic and phenotypic data. The name Tsukamurella pulmonis sp. nov. is proposed for this organism; the type strain is IMMIB D-1321T (= DSM 44142T). This isolate shows 44.2 and 36.2% DNA relatedness to Tsukamurella paurometabola DSM 20162T (T = type strain) and Tsukamurella inchonensis DSM 44067T, respectively.

  19. Ethylene Glycol Metabolism by Pseudomonas putida

    OpenAIRE

    Mückschel, Björn; Simon, Oliver; Klebensberger, Janosch; Graf, Nadja; Rosche, Bettina; Altenbuchner, Josef; Pfannstiel, Jens; Huber, Armin; Hauer, Bernhard

    2012-01-01

    In this study, we investigated the metabolism of ethylene glycol in the Pseudomonas putida strains KT2440 and JM37 by employing growth and bioconversion experiments, directed mutagenesis, and proteome analysis. We found that strain JM37 grew rapidly with ethylene glycol as a sole source of carbon and energy, while strain KT2440 did not grow within 2 days of incubation under the same conditions. However, bioconversion experiments revealed metabolism of ethylene glycol by both strains, with the...

  20. Dynamics of Pseudomonas aeruginosa genome evolution

    OpenAIRE

    Mathee, Kalai; Narasimhan, Giri; Valdes, Camilo; Qiu, Xiaoyun; Matewish, Jody M.; Koehrsen, Michael; Rokas, Antonis; Yandava, Chandri N.; Engels, Reinhard; Zeng, Erliang; Olavarietta, Raquel; Doud, Melissa; Smith, Roger S.; Montgomery, Philip; White, Jared R.

    2008-01-01

    One of the hallmarks of the Gram-negative bacterium Pseudomonas aeruginosa is its ability to thrive in diverse environments that includes humans with a variety of debilitating diseases or immune deficiencies. Here we report the complete sequence and comparative analysis of the genomes of two representative P. aeruginosa strains isolated from cystic fibrosis (CF) patients whose genetic disorder predisposes them to infections by this pathogen. The comparison of the genomes of the two CF strains...

  1. [Clinical features of Pseudomonas aeruginosa infections].

    Science.gov (United States)

    Sarlangue, J; Brissaud, O; Labrèze, C

    2006-10-01

    Pseudomonas aeruginosa is a ubiquitous environmental organism usually considered as opportunistic pathogen in immunocompromised subjects. However it can produce disease in healthy children, mainly on moist body sites. Familial, community and nosocomial outbreaks of cutaneous infections have been reported. Ecthyma gangrenosum is possible without bacteremia. P. aeruginosa is also the most common cause of otitis externa in swimmers and osteomyelitis after puncture wound of the foot.

  2. Using Pseudomonas spp. for Integrated Biological Control.

    Science.gov (United States)

    Stockwell, Virginia O; Stack, James P

    2007-02-01

    ABSTRACT Pseudomonas spp. have been studied for decades as model organisms for biological control of plant disease. Currently, there are three commercial formulations of pseudomonads registered with the U.S. Environmental Protection Agency for plant disease suppression, Bio-Save 10 LP, Bio-Save 11 LP, and BlightBan A506. Bio-Save 10 LP and Bio-Save 11 LP, products of Jet Harvest Solutions, Longwood, FL, contain Pseudomonas syringae strains ESC-10 and ESC-11, respectively. These products are applied in packinghouses to prevent postharvest fungal diseases during storage of citrus, pome, stone fruits, and potatoes. BlightBan A506, produced by NuFarm Americas, Burr Ridge, IL, contains P. fluorescens strain A506. BlightBan A506 is applied primarily to pear and apple trees during bloom to suppress the bacterial disease fire blight. Combining BlightBan A506 with the antibiotic streptomycin improves control of fire blight, even in areas with streptomycin-resistant populations of the pathogen. BlightBan A506 also may reduce fruit russet and mild frost injury. These biocontrol products consisting of Pseudomonas spp. provide moderate to excellent efficacy against multiple production constraints, are relatively easy to apply, and they can be integrated with conventional products for disease control. These characteristics will contribute to the adoption of these products by growers and packinghouses.

  3. Isolation and Identification of Antifungal N-Butylbenzenesulphonamide Produced by Pseudomonas sp. AB2

    National Research Council Canada - National Science Library

    KIM, KEUN KI; KANG, JAE GON; MOON, SUK SIK; KANG, KYU YOUNG

    2000-01-01

    .... An antifungal antibiotic was isolated from the culture filtrate and was identified as N-butylbenzenesulphonamide. ED50 values of the N-butylbenzenesulphonamide against P. ultimum, P. capsici, R. solani, and B. cinerea were 73, 41, 33 and 102 ppm, respectively.

  4. Application of Pseudomonas sp. strain DCA1 for the removal of chlorinated hydrocarbons

    NARCIS (Netherlands)

    Hage, J.C.

    2004-01-01

    The large-scale application of chlorinated aliphatic hydrocarbons (CAHs) has resulted in many cases of groundwater contamination. Contaminated groundwater can be remediated by pump-and-treat: the groundwater is pumped to the surface and treated. The groundwater can be treated in bioreactors, in whic

  5. Pseudomonas sp. as a Source of Medium Chain Length Polyhydroxyalkanoates for Controlled Drug Delivery: Perspective

    Directory of Open Access Journals (Sweden)

    Sujatha Kabilan

    2012-01-01

    Full Text Available Controlled drug delivery technology represents one of the most rapidly advancing areas of science. They offer numerous advantages compared to conventional dosage forms including improved efficacy, reduced toxicity, improved patient compliance and convenience. Over the past several decades, many delivery tools or methods were developed such as viral vector, liposome-based delivery system, polymer-based delivery system, and intelligent delivery system. Recently, nonviral vectors, especially those based on biodegradable polymers, have been widely investigated as vectors. Unlike the other polymers tested, polyhydroxyalkanoates (PHAs have been intensively investigated as a family of biodegradable and biocompatible materials for in vivo applications as implantable tissue engineering material as well as release vectors for various drugs. On the other hand, the direct use of these polyesters has been hampered by their hydrophobic character and some physical shortcomings, while its random copolymers fulfilled the expectation of biomedical researchers by exhibiting significant mechanical and thermal properties. This paper reviews the strategies adapted to make functional polymer to be utilized as delivery system.

  6. Pseudomonas kuykendallii sp. nov.: A novel y-Proteobacteria isolated from a hexazinone degrading bioreactor

    Science.gov (United States)

    Three strains of Gram-negative bacteria designated strains H2T, H6, and H7 were isolated from bioreactors that degraded the herbicide hexazinone. Similar morphological characteristics, cellular fatty acid profiles and 16S rRNA gene sequences show that the isolates are members of the same species. ...

  7. Improvement of Properties of Pseudomonas sp. Lipase in Resolution of 2-Octanol

    Institute of Scientific and Technical Information of China (English)

    WANG Zhi; QUAN Jing; WENG Liang; ZHENG Liang-yu; LIU Ning; DONG Huan; CAO Shu-gui

    2003-01-01

    A novel preparation method was developed to form a surfactant-lipase complex for the resolution of 2-octanol in a solvent-free system. The E value was improved from 6.64 to 120.2. The lipase modified by the anionic surfactant possessed a low solubility in the solvent-free system, which was beneficial to the recovery and the repeated usage of the lipase. The surfactant-lipase complex maintained a high enantioselectivity after five cycles of usage. The effect of water on both the activity and the enantioselectivity of the lipase has also been investigated; the direct addition of a salt hydrate pair of Na4P2O7*H2O and Na4P2O7 can dramatically activate the modified enzyme.

  8. Purification of Pseudomonas sp. Lipase by Continuous Elution Electrophoresis Based on Pb2+ Precipitation Method

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hua-li; WANG Zhi; LIU Bin; WANG Xue-li; CAO Shu-gui; LI Zheng-qiang

    2005-01-01

    A Pb2+ precipitation method was designed to get rid of the impure proteins in a lipase. The results show that it was a simple way in the primary treatment of the crude samples and about 20% impure proteins were removed in the precipitation step. Further, continuous elution electrophoresis was also applied as a preparative technique for attaining the highly pure lipase. During the continuous elution electrophoresis, the enzyme was eluted as a single peak and 5.7-fold purification was achieved in a yield of 54.3%. The two steps finally yielded an electrophoretically homogeneous enzyme.

  9. Attenuation of Pseudomonas aeruginosa virulence by marine invertebrate–derived Streptomyces sp.

    Digital Repository Service at National Institute of Oceanography (India)

    Naik, D.N.; Wahidullah, S.; Meena, R.M.

    -mediated virulence factors like swarming, biofilm formation, pyocyanin, rhamnolipid and LasA production in Ps. aeruginosa ATCC 27853. The isolates NIO 10068, NIO 10058 and NIO 10090 exhibited very good anti-QS activity, with NIO 10068 being the most promising one...

  10. Introduction of Atrazine-Degrading Pseudomonas SP. Strain ADP to Enhance Phytoremediation of Atrazine

    Science.gov (United States)

    Atrazine (ATR) has been widely applied in the US Midwestern states. Public health and ecological concerns have been raised about contamination of surface and ground water by ATR and its chlorinated metabolites, due to their toxicity and potential carcinogenic or endocrinology effects. Phytoremediati...

  11. Why does the healthy cornea resist Pseudomonas aeruginosa infection?

    Science.gov (United States)

    Evans, David J; Fleiszig, Suzanne M J

    2013-06-01

    To provide our perspective on why the cornea is resistant to infection based on our research results with Pseudomonas (P) aeruginosa. We focus on our current understanding of the interplay between bacteria, tear fluid, and the corneal epithelium that determines health as the usual outcome, and propose a theoretical model for how contact lens wear might change those interactions to enable susceptibility to P aeruginosa infection. Use of "null-infection" in vivo models, cultured human corneal epithelial cells, contact lens-wearing animal models, and bacterial genetics help to elucidate mechanisms by which P aeruginosa survives at the ocular surface, adheres, and traverses multilayered corneal epithelia. These models also help elucidate the molecular mechanisms of corneal epithelial innate defense. Tear fluid and the corneal epithelium combine to make a formidable defense against P aeruginosa infection of the cornea. Part of that defense involves the expression of antimicrobials such as β-defensins, the cathelicidin LL-37, cytokeratin-derived antimicrobial peptides, and RNase7. Immunomodulators such as SP-D and ST2 also contribute. Innate defenses of the cornea depend in part on MyD88, a key adaptor protein of TLR and IL-1R signaling, but the basal lamina represents the final barrier to bacterial penetration. Overcoming these defenses involves P aeruginosa adaptation, expression of the type III secretion system, proteases, and P aeruginosa biofilm formation on contact lenses. After more than 2 decades of research focused on understanding how contact lens wear predisposes to P aeruginosa infection, our working hypothesis places blame for microbial keratitis on bacterial adaptation to ocular surface defenses, combined with changes to the biochemistry of the corneal surface caused by trapping bacteria and tear fluid against the cornea under the lens. Copyright © 2013 Elsevier Inc. All rights reserved.

  12. An altered Pseudomonas diversity is recovered from soil by using nutrient-poor Pseudomonas-selective soil extract media

    DEFF Research Database (Denmark)

    Aagot, N.; Nybroe, O.; Nielsen, P.

    2001-01-01

    . Several of these analyses showed that the amount of Casamino Acids significantly influenced the diversity of the recovered Pseudomonas isolates. Furthermore, the data suggested that specific Pseudomonas subpopulations were represented on the nutrient-poor media. The NAA 1:100 medium, containing ca. 15 mg......We designed five Pseudomonas-selective soil extract NAA media containing the selective properties of trimethoprim and sodium lauroyl sarcosine and 0 to 100% of the amount of Casamino Acids used in the classical Pseudomonas-selective Gould's S1 medium. All of the isolates were confirmed...

  13. Comparison of Substrate Specificity of Escherichia Coli p-Aminobenzoyl-Glutamate Hydrolase with Pseudomonas Carboxypeptidase G

    Science.gov (United States)

    Larimer, Cassandra M.; Slavnic, Dejan; Pitstick, Lenore D.; Green, Jacalyn M.

    2016-01-01

    Reduced folic acid derivatives support biosynthesis of DNA, RNA and amino acids in bacteria as well as in eukaryotes, including humans. While the genes and steps for bacterial folic acid synthesis are known, those associated with folic acid catabolism are not well understood. A folate catabolite found in both humans and bacteria is p-aminobenzoyl-glutamate (PABA-GLU). The enzyme p-aminobenzoyl-glutamate hydrolase (PGH) breaks down PABA-GLU and is part of an apparent operon, the abg region, in E. coli. The subunits of PGH possess sequence and catalytic similarities to carboxypeptidase enzymes from Pseudomonas species. A comparison of the subunit sequences and activity of PGH, relative to carboxypeptidase enzymes, may lead to a better understanding of bacterial physiology and pathway evolution. We first compared the amino acid sequences of AbgA, AbgB and carboxypeptidase G2 from Pseudomonas sp. RS-16, which has been crystallized. Then we compared the enzyme activities of E. coli PGH and commercially available Pseudomonas carboxypeptidase G using spectrophotometric assays measuring cleavage of PABA-GLU, folate, aminopterin, methotrexate, 5-formyltetrahydrofolate, and 5-methyltetrahydrofolate. The Km and Vmax values for the folate and anti-folate substrates of PGH could not be determined, because the instrument reached its limit before the enzyme was saturated. Therefore, activity of PGH was compared to the activity of CPG, or normalized to PABA-GLU (nmole/min/µg). Relative to its activity with 10 µM PABA-GLU (100%), PGH cleaved glutamate from methotrexate (48%), aminopterin (45%) and folate (9%). Reduced folates leucovorin (5-formyltetrahydrofolate) and 5-methyltetrahydrofolate were not cleaved by PGH. Our data suggest that E. coli PGH is specific for PABA-GLU as its activity with natural folates (folate, 5-methyltetrahydrofolate, and leucovorin) was very poor. It does, however, have some ability to cleave anti-folates which may have clinical applications in

  14. Diversity of endophytic Pseudomonas in Halimione portulacoides from metal(loid)-polluted salt marshes.

    Science.gov (United States)

    Rocha, Jaqueline; Tacão, Marta; Fidalgo, Cátia; Alves, Artur; Henriques, Isabel

    2016-07-01

    Phytoremediation assisted by bacteria is seen as a promising alternative to reduce metal contamination in the environment. The main goal of this study was to characterize endophytic Pseudomonas isolated from Halimione portulacoides, a metal-accumulator plant, in salt marshes contaminated with metal(loid)s. Phylogenetic analysis based on 16S rRNA and gyrB genes showed that isolates affiliated with P. sabulinigri (n = 16), P. koreensis (n = 10), P. simiae (n = 5), P. seleniipraecipitans (n = 2), P. guineae (n = 2), P. migulae (n = 1), P. fragi (n = 1), P. xanthomarina (n = 1), and Pseudomonas sp. (n = 1). Most of these species have never been described as endophytic. The majority of the isolates were resistant to three or more metal(loid)s. Antibiotic resistance was frequent among the isolates but most likely related to species-intrinsic features. Common acquired antibiotic resistance genes and integrons were not detected. Plasmids were detected in 43.6 % of the isolates. Isolates that affiliated with different species shared the same plasmid profile but attempts to transfer metal resistance to receptor strains were not successful. Phosphate solubilization and IAA production were the most prevalent plant growth promoting traits, and 20 % of the isolates showed activity against phytopathogenic bacteria. Most isolates produced four or more extracellular enzymes. Preliminary results showed that two selected isolates promote Arabidopsis thaliana root elongation. Results highlight the diversity of endophytic Pseudomonas in H. portulacoides from contaminated sites and their potential to assist phytoremediation by acting as plant growth promoters and as environmental detoxifiers.

  15. Expression, purification, crystallization and preliminary X-ray analysis of Pseudomonas aeruginosa AlgX

    Energy Technology Data Exchange (ETDEWEB)

    Weadge, J.T.; Robinson, H.; Yip, P. P.; Arnett, K.; Tipton, P. A.; Howell, P. L.

    2010-05-01

    AlgX is a periplasmic protein required for the production of the exopolysaccharide alginate in Pseudomonas sp. and Azotobacter vinelandii. AlgX has been overexpressed and purified and diffraction-quality crystals have been grown using iterative seeding and the hanging-drop vapor-diffusion method. The crystals grew as flat plates with unit-cell parameters a = 46.4, b = 120.6, c = 86.9 {angstrom}, {beta} = 95.7{sup o}. The crystals exhibited the symmetry of space group P2{sub 1} and diffracted to a minimum d-spacing of 2.1 {angstrom}. On the basis of the Matthews coefficient (V{sub M} = 2.25 {angstrom}{sup 3} Da{sup -1}), two molecules were estimated to be present in the asymmetric unit.

  16. Novel, Pseudomonas-derived Antifungal Lipopeptides From A Disease Suppressive Soil In Greenlandic Potato Fields

    DEFF Research Database (Denmark)

    Hennessy, Rosanna Catherine; Michelsen, Charlotte F.; Glaring, Mikkel A.;

    2015-01-01

    Potato cultivation in southwest Greenland omits the use of pesticides, relies on limited crop rotations, and despite the presence of plant pathogenic fungi in the soil, has not suffered from severe disease outbreaks. In this presentation, the bacterial strain Pseudomonas sp. In5 which significantly...... contributes to the suppressiveness of soil at Inneruulalik in southern Greenland will be explored. A combination of molecular genetics and genomics coupled with matrix-assisted laser desorption ionization – time of flight (MALDI-TOF) imaging mass spectrometry (IMS) identified a large genomic island encoding...... the two non-ribosomal peptides nunapeptin and nunamycin, which are key components of the antifungal activity of In5. Bacterial-fungal interaction studies uncovered a complex interaction whereby nunamycin appears most active against Rhizoctonia solani with no antimicrobial effect against the oomycete...

  17. Acetobacter intermedius, sp. nov.

    Science.gov (United States)

    Boesch, C; Trcek, J; Sievers, M; Teuber, M

    1998-03-01

    Strains of a new species in the genus Acetobacter, for which we propose the name A. intermedius sp. nov., were isolated and characterized in pure culture from different sources (Kombucha beverage, cider vinegar, spirit vinegar) and different countries (Switzerland, Slovenia). The isolated strains grow in media with 3% acetic acid and 3% ethanol as does A. europaeus, do, however, not require acetic acid for growth. These characteristics phenotypically position A. intermedius between A. europaeus and A. xylinus, DNA-DNA hybridizations of A. intermedius-DNA with DNA of the type strains of Acetobacter europaeus, A. xylinus, A. aceti, A. hansenii, A. liquefaciens, A. methanolicus, A. pasteurianus, A. diazotrophicus, Gluconobacter oxydans and Escherichia coli HB 101 indicated less than 60% DNA similarity. The important features of the new species are described. Acetobacter intermedius strain TF2 (DSM11804) isolated from the liquid phase of a tea fungus beverage (Kombucha) is the type strain.

  18. Tsukamurella tyrosinosolvens sp. nov.

    Science.gov (United States)

    Yassin, A F; Rainey, F A; Burghardt, J; Brzezinka, H; Schmitt, S; Seifert, P; Zimmermann, O; Mauch, H; Gierth, D; Lux, I; Schaal, K P

    1997-07-01

    Chemotaxonomic and 16S ribosomal DNA sequence analyses of four bacterial isolates from blood cultures from patients with cardiac pacemaker implants and sputa of patients with chronic lung infections clearly demonstrated that these bacteria belong to the genus Tsukamurella. DNA-DNA hybridization data, as well as the physiological characteristics of the isolates, indicate that they are closely related and belong to a single species that differs from previously described members of the genus Tsukamurella. The name Tsukamurella tyrosinosolvens sp. nov. is proposed for these isolates, and the new species is represented by strain IMMIB D-1397T (= DSM 44234T). Strain IMMIB D-1397T exhibits 53.4, 53.5, and 54.7% DNA-DNA relatedness to Tsukamurella paurometabola DSM 20162T, Tsukamurella inchonensis DSM 44067T, and Tsukamurella pulmonis DSM 44142T, respectively.

  19. High quality draft genome sequences of Pseudomonas fulva DSM 17717(T), Pseudomonas parafulva DSM 17004(T) and Pseudomonas cremoricolorata DSM 17059(T) type strains.

    Science.gov (United States)

    Peña, Arantxa; Busquets, Antonio; Gomila, Margarita; Mulet, Magdalena; Gomila, Rosa M; Reddy, T B K; Huntemann, Marcel; Pati, Amrita; Ivanova, Natalia; Markowitz, Victor; García-Valdés, Elena; Göker, Markus; Woyke, Tanja; Klenk, Hans-Peter; Kyrpides, Nikos; Lalucat, Jorge

    2016-01-01

    Pseudomonas has the highest number of species out of any genus of Gram-negative bacteria and is phylogenetically divided into several groups. The Pseudomonas putida phylogenetic branch includes at least 13 species of environmental and industrial interest, plant-associated bacteria, insect pathogens, and even some members that have been found in clinical specimens. In the context of the Genomic Encyclopedia of Bacteria and Archaea project, we present the permanent, high-quality draft genomes of the type strains of 3 taxonomically and ecologically closely related species in the Pseudomonas putida phylogenetic branch: Pseudomonas fulva DSM 17717(T), Pseudomonas parafulva DSM 17004(T) and Pseudomonas cremoricolorata DSM 17059(T). All three genomes are comparable in size (4.6-4.9 Mb), with 4,119-4,459 protein-coding genes. Average nucleotide identity based on BLAST comparisons and digital genome-to-genome distance calculations are in good agreement with experimental DNA-DNA hybridization results. The genome sequences presented here will be very helpful in elucidating the taxonomy, phylogeny and evolution of the Pseudomonas putida species complex.

  20. Evaluation and biochemical characterization of a distinctive pyoverdin from a pseudomonas isolated from chickpea rhizosphere

    Directory of Open Access Journals (Sweden)

    Neelam Tank

    2012-06-01

    Full Text Available Microbial siderophores confiscate the available ferric ions around the roots and trigger a reaction resulting in plant growth promotion. In our study, a high level of siderophore production was observed from a newly isolated Pseudomonas sp. from the rhizosphere of Chickpea plants. Under an iron depleted condition in Standard Succinic acid medium a 1000 µgmL-1 of siderophore production was achieved. Increasing the concentration of iron showed an inverse relationship between growth and siderophore production. Fourier Transform Infrared Spectroscopy (FTIR analysis of the purified crystals, its UV spectral analysis and High Pressure Liquid Chromatography (HPLC revealed the identity of the siderophore as similar to that of pyoverdin with distinctive characters. Electron spray ionization mass spectroscopy (ESIMS shows presence of abundance of A1 ions (419 m/z and branching of amino acids from B1-B5. This pyoverdin contains a cyclic tetra peptide but Serine and Arginine are missing. Based on our analysis and deviations from the reported structure of pyoverdin it is suggested that this pseudomonas produces distinctly characterized pyoverdin siderophore.

  1. Crystal structure of the terminal oxygenase component of cumene dioxygenase from Pseudomonas fluorescens IP01.

    Science.gov (United States)

    Dong, Xuesong; Fushinobu, Shinya; Fukuda, Eriko; Terada, Tohru; Nakamura, Shugo; Shimizu, Kentaro; Nojiri, Hideaki; Omori, Toshio; Shoun, Hirofumi; Wakagi, Takayoshi

    2005-04-01

    The crystal structure of the terminal component of the cumene dioxygenase multicomponent enzyme system of Pseudomonas fluorescens IP01 (CumDO) was determined at a resolution of 2.2 A by means of molecular replacement by using the crystal structure of the terminal oxygenase component of naphthalene dioxygenase from Pseudomonas sp. strain NCIB 9816-4 (NphDO). The ligation of the two catalytic centers of CumDO (i.e., the nonheme iron and Rieske [2Fe-2S] centers) and the bridging between them in neighboring catalytic subunits by hydrogen bonds through a single amino acid residue, Asp231, are similar to those of NphDO. An unidentified external ligand, possibly dioxygen, was bound at the active site nonheme iron. The entrance to the active site of CumDO is different from the entrance to the active site of NphDO, as the two loops forming the lid exhibit great deviation. On the basis of the complex structure of NphDO, a biphenyl substrate was modeled in the substrate-binding pocket of CumDO. The residues surrounding the modeled biphenyl molecule include residues that have already been shown to be important for its substrate specificity by a number of engineering studies of biphenyl dioxygenases.

  2. Resistance of Pseudomonas to Quaternary Ammonium Compounds. I. Growth in Benzalkonium Chloride Solution

    Science.gov (United States)

    Adair, Frank W.; Geftic, Sam G.; Gelzer, Justus

    1969-01-01

    Resistant cells of Pseudomonas aeruginosa and a waterborne Pseudomonas sp. (strain Z-R) were able to multiply in nitrogen-free minimal salts solution containing various concentrations of commercially prepared, ammonium acetate-buffered benzalkonium chloride (CBC), a potent antimicrobial agent. As the CBC concentration increased, growth increased until a point was reached at which the extent of growth leveled off or was completely depressed. Minimal salts solutions of pure benzalkonium chloride (PBC) containing no ammonium acetate did not support bacterial growth. When ammonium acetate was added to PBC solutions in the same concentrations found in CBC solutions, growth patterns developed that were comparable to those found with CBC. Likewise, (NH4)2SO4 added to PBC solutions supported growth of both organisms. P. aeruginosa was initially resistant to CBC levels of 0.02% and it was adapted to tolerate levels as high as 0.36%. Strain Z-R was naturally resistant to 0.4% CBC. Since ammonium acetate, carried over by the CBC used in drug formulations and disinfectant solutions, has the potential to support the growth of resistant bacteria and thus make possible the risk of serious infection, it is suggested that regulations allowing the presence of ammonium acetate in CBC solution be reconsidered. PMID:4984761

  3. Degradation kinetics and pathway of phenol by Pseudomonas and Bacillus species.

    Science.gov (United States)

    Hasan, Syed Adnan; Jabeen, Suraiya

    2015-01-02

    This article elucidates that strain Pseudomonas aeruginosa (IES-Ps-1) is a versatile toxic organic compound degrader. With the degradation of malathion and cypermethrin (studied by other researchers previously), this strain was able to degrade phenol. Two other indigenous soil flora (i.e., Pseudomonas sp. (IES-S) and Bacillus subtilis (IES-B)) were also found to be potential phenol degraders. Phenol was degraded with Monod kinetics during growth in nutrient broth and mineral salts medium. Before entering into the growth inhibition phase, strains IES-Ps-1, IES-S and IES-B could tolerate up to 400, 700 and 500 mg/L phenol, respectively, when contained in nutrient broth. However, according to the Luong-Levenspiel model, the growth of strains IES-Ps-1, IES-S and IES-B would cease at 2000, 2174 and 2190 mg/L phenol, respectively. Strain IES-Ps-1 degraded 700, 900 and 1050 mg/L phenol contained in mineral salts medium with the specific rates of 0.034, 0.075 and 0.021 h(-1), respectively. All these strains grew by making clusters when exposed to phenol in order to prevent damages due to high substrate concentration. These strains transformed phenol into catechol, which was then degraded via ortho-cleavage pathway.

  4. Synthesis of rhamnolipid biosurfactant and mode of hexadecane uptake by Pseudomonas species

    Directory of Open Access Journals (Sweden)

    Singh Pooja

    2009-03-01

    Full Text Available Abstract Background Microorganisms have devised ways by which they increase the bioavailability of many water immiscible substrates whose degradation rates are limited by their low water solubility. Hexadecane is one such water immiscible hydrocarbon substrate which forms an important constituent of oil. One major mechanism employed by hydrocarbon degrading organisms to utilize such substrates is the production of biosurfactants. However, much of the overall mechanism by which such organisms utilize hydrocarbon substrate still remains a mystery. Results With an aim to gain more insight into hydrocarbon uptake mechanism, an efficient biosurfactant producing and n-hexadecane utilizing Pseudomonas sp was isolated from oil contaminated soil which was found to produce rhamnolipid type of biosurfactant containing a total of 13 congeners. Biosurfactant action brought about the dispersion of hexadecane to droplets smaller than 0.22 μm increasing the availability of the hydrocarbon to the degrading organism. Involvement of biosurfactant was further confirmed by electron microscopic studies. Biosurfactant formed an emulsion with hexadecane thereby facilitating increased contact between hydrocarbon and the degrading bacteria. Interestingly, it was observed that "internalization" of "biosurfactant layered hydrocarbon droplet" was taking place suggesting a mechanism similar in appearance to active pinocytosis, a fact not earlier visually reported in bacterial systems for hydrocarbon uptake. Conclusion This study throws more light on the uptake mechanism of hydrocarbon by Pseudomonas aeruginosa. We report here a new and exciting line of research for hydrocarbon uptake involving internalization of biosurfactant covered hydrocarbon inside cell for subsequent breakdown.

  5. Antibiofilm Activity of the Marine Bacterium Pseudoalteromonas sp. Strain 3J6▿

    Science.gov (United States)

    Dheilly, Alexandra; Soum-Soutéra, Emmanuelle; Klein, Géraldine L.; Bazire, Alexis; Compère, Chantal; Haras, Dominique; Dufour, Alain

    2010-01-01

    Biofilm formation results in medical threats or economic losses and is therefore a major concern in a variety of domains. In two-species biofilms of marine bacteria grown under dynamic conditions, Pseudoalteromonas sp. strain 3J6 formed mixed biofilms with Bacillus sp. strain 4J6 but was largely predominant over Paracoccus sp. strain 4M6 and Vibrio sp. strain D01. The supernatant of Pseudoalteromonas sp. 3J6 liquid culture (SN3J6) was devoid of antibacterial activity against free-living Paracoccus sp. 4M6 and Vibrio sp. D01 cells, but it impaired their ability to grow as single-species biofilms and led to higher percentages of nonviable cells in 48-h biofilms. Antibiofilm molecules of SN3J6 were able to coat the glass surfaces used to grow biofilms and reduced bacterial attachment about 2-fold, which might partly explain the biofilm formation defect but not the loss of cell viability. SN3J6 had a wide spectrum of activity since it affected all Gram-negative marine strains tested except other Pseudoalteromonas strains. Biofilm biovolumes of the sensitive strains were reduced 3- to 530-fold, and the percentages of nonviable cells were increased 3- to 225-fold. Interestingly, SN3J6 also impaired biofilm formation by three strains belonging to the human-pathogenic species Pseudomonas aeruginosa, Salmonella enterica, and Escherichia coli. Such an antibiofilm activity is original and opens up a variety of applications for Pseudoalteromonas sp. 3J6 and/or its active exoproducts in biofilm prevention strategies. PMID:20363799

  6. Biosynthesis and regulation of cyclic lipopeptides in Pseudomonas fluorescens

    NARCIS (Netherlands)

    Bruijn, de I.

    2009-01-01

    Cyclic lipopeptides (CLPs) are surfactant and antibiotic metabolites produced by a variety of bacterial genera. For the genus Pseudomonas, many structurally different CLPs have been identified. CLPs play an important role in surface motility of Pseudomonas strains, but also in virulence and

  7. Biosynthesis and regulation of cyclic lipopeptides in Pseudomonas fluorescens

    NARCIS (Netherlands)

    Bruijn, de I.

    2009-01-01

    Cyclic lipopeptides (CLPs) are surfactant and antibiotic metabolites produced by a variety of bacterial genera. For the genus Pseudomonas, many structurally different CLPs have been identified. CLPs play an important role in surface motility of Pseudomonas strains, but also in virulence and attac

  8. Novel Targets for Treatment of Pseudomonas aeruginosa Biofilms

    DEFF Research Database (Denmark)

    Alhede, Morten; Alhede, Maria; Bjarnsholt, Thomas

    2014-01-01

    Pseudomonas aeruginosa causes infection in all parts of the human body. The bacterium is naturally resistant to a wide range of antibiotics. In addition to resistance mechanisms such as efflux pumps, the ability to form aggregates, known as biofilm, further reduces Pseudomonas aeruginosa’s...

  9. Interactions between biosurfactant-producing Pseudomonas and Phytophthora species

    NARCIS (Netherlands)

    Tran, H.

    2007-01-01

    Fluorescent Pseudomonas bacteria produce a wide variety of antimicrobial metabolites, including soap-like compounds referred to as biosurfactants. The results of this thesis showed that biosurfactant-producing Pseudomonas bacteria are effective in controlling Phytophthora foot rot disease of black p

  10. Facial Nerve Paralysis seen in Pseudomonas sepsis with ecthyma gangrenosum

    Directory of Open Access Journals (Sweden)

    Suleyman Ozdemir

    2013-02-01

    Full Text Available Ecthyma gangrenosum is a skin lesion which is created by pseudomonas auriginosa. Peripheral facial paralysis and mastoiditis as a rare complication of otitis media induced by pseudomonas auriginosa.In this study, 4 months child who has ecthyma gangrenosum and facial nerve paralysis was reported. [Cukurova Med J 2013; 38(1.000: 126-130

  11. Typing of Pseudomonas aeruginosa strains in Norwegian cystic fibrosis patients

    DEFF Research Database (Denmark)

    Fluge, G; Ojeniyi, B; Høiby, N

    2001-01-01

    OBJECTIVES: Typing of Pseudomonas aeruginosa isolates from Norwegian cystic fibrosis (CF) patients with chronic Pseudomonas lung infection in order to see whether cross-infection might have occurred. METHODS: Isolates from 60 patients were collected during the years 1994-98, and typed by pulsed...

  12. Distribution, diversity, and activity of antibiotic-producing Pseudomonas spp.

    NARCIS (Netherlands)

    Souza, de J.T.

    2002-01-01

    Bacteria of the genus Pseudomonas are potential biocontrol agents of plant diseases caused by various fungi and oomycetes. Antibiotic production is an important trait responsible for the activity of several Pseudomonas strains against plant pathogens. Despite the amount of informati

  13. Distribution, diversity, and activity of antibiotic-producing Pseudomonas spp.

    NARCIS (Netherlands)

    Souza, de J.T.

    2002-01-01

    Bacteria of the genus Pseudomonas are potential biocontrol agents of plant diseases caused by various fungi and oomycetes. Antibiotic production is an important trait responsible for the activity of several Pseudomonas

  14. Verspreiding, diversiteit en activiteit van antibioticaproducerende Pseudomonas spp

    NARCIS (Netherlands)

    Souza, J.T.

    2003-01-01

    Pseudomonas bacteriën zijn potentiële antagonisten van diverse plantenpathogene schimmels en oömyceten. De productie van antibiotica speelt een belangrijke rol in de activiteit van diverse Pseudomonas isolaten tegen plantenpathogenen. Dit artikel is een samenvatting van het proefschrift getiteld 'Di

  15. Pseudomonas Exotoxin A: optimized by evolution for effective killing

    Directory of Open Access Journals (Sweden)

    Marta eMichalska

    2015-09-01

    Full Text Available Pseudomonas Exotoxin A (PE is the most toxic virulence factor of the pathogenic bacterium Pseudomonas aeruginosa. This review describes current knowledge about the intoxication pathways of PE. Moreover, PE represents a remarkable example for pathoadaptive evolution, how bacterial molecules have been structurally and functionally optimized under evolutionary pressure to effectively impair and kill their host cells.

  16. Suppression of Aspergillus by Pseudomonas aeruginosa

    DEFF Research Database (Denmark)

    Jensen, Britt Guillaume; Jelsbak, Lars; Søndergaard, Ib

    Objectives: Cystic fibrosis patients are commonly infected by Pseudomonas aeruginosa, but Aspergilli are also frequently isolated. Our aim was to examine the possible interaction between P. aeruginosa and different Aspergillus. Methods: A suspension of 106 fungal spores/ml was streaked onto WATM...... suppressed growth of A. fumigatus, A. niger, A. flavus, A. oryzae, A. terreus and E. nidulans. HPLC and LC-DAD-MS results showed an increase in phenazine-1-carboxylic acid and phenazine-1-carboxamide production by P. aeruginosa in the contact area of Aspergillus. Different quinolones were also identified...

  17. INHIBITION OF PATHOGENS BY SPOROGENIC BACTERIA ISOLATED FROM HONEY OF Melipona sp. (APIDAE: APINAE: MELIPONINI

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    KELY DAMIANA NOVAES DA SILVA

    2016-01-01

    Full Text Available The aim of this study was to isolate sporogenic bacteria from the honey of stingless bees Melipona sp., in dry forest, and to evaluate their antagonistic potential for medicinal employment purposes and animal production. The honey samples were collected in Serra Talhada - PE, where honey was taken from four different hives (in triplicate, totaling 12 samples. The samples were diluted and subjected to 80 ºC for 20 minutes to eliminate vegetative cells. The dilutions were plated onto nutrient agar and incubated at 30 ºC for 72 hours. Then the colony forming units (CFU were quantified. The samples were also plated onto malt agar and Sabouraud agar, and incubated at 30 ºC for 14 days for the growth of yeast and molds. Total and fecal coliforms were quantified by the most probable number method (MPN. Seven isolates (I of sporogenic bacteria ( Bacillus were obtained, however only four showed probiotic potential. Isolate I - 5 showed the greatest probiotic potential and inhibited the growth of Escherichia coli , Klebsiella sp., Pseudomonas aeruginosa, Salmonella sp., and Staphylococcus aureus . The growth of the Sarcina sp. was not inhibited by any isolate. No yeast, molds or coliforms were found. The Melipona sp. honey is a source of spore - forming bacteria and is antagonistic to microorganisms that contaminate honey. It has good microbiological quality.

  18. Biochemical basis of mercury remediation and bioaccumulation by Enterobacter sp. EMB21.

    Science.gov (United States)

    Sinha, Arvind; Kumar, Sumit; Khare, Sunil Kumar

    2013-01-01

    The aims of this study were to isolate metal bioaccumulating bacterial strains and to study their applications in removal of environmental problematic heavy metals like mercury. Five bacterial strains belonging to genera Enterobacter, Bacillus, and Pseudomonas were isolated from oil-spilled soil. Among these, one of the strains Enterobacter sp. EMB21 showed mercury bioaccumulation inside the cells simultaneous to its bioremediation. The bioaccumulation of remediated mercury was confirmed by transmission electron microscopy and energy dispersive X-ray. The mercury-resistant loci in the Enterobacter sp. EMB21 cells were plasmid-mediated as confirmed by transformation of mercury-sensitive Escherichia coli DH5α by Enterobacter sp. EMB21 plasmid. Effect of different culture parameters viz-a-viz inoculum size, pH, carbon, and nitrogen source revealed that alkaline pH and presence of dextrose and yeast extract favored better remediation. The results indicated the usefulness of Enterobacter sp. EMB21 for the effective remediation of mercury in bioaccumulated form. The Enterobacter sp. EMB21 seems promising for heavy metal remediation wherein the remediated metal can be trapped inside the cells. The process can further be developed for the synthesis of valuable high-end functional alloy, nanoparticles, or metal conjugates from the metal being remediated.

  19. Vaccines for preventing infection with Pseudomonas aeruginosa in cystic fibrosis

    DEFF Research Database (Denmark)

    Johansen, H.K.; Gøtzsche, Peter C.; Johansen, Helle Krogh

    2008-01-01

    BACKGROUND: Chronic pulmonary infection in cystic fibrosis results in progressive lung damage. Once colonisation of the lungs with Pseudomonas aeruginosa occurs, it is almost impossible to eradicate. Vaccines, aimed at reducing infection with Pseudomonas aeruginosa, have been developed. OBJECTIVES......: To assess the effectiveness of vaccination against Pseudomonas aeruginosa in cystic fibrosis. SEARCH STRATEGY: We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register using the terms vaccines AND pseudomonas (last search May 2008) and PubMed using the terms vaccin* AND cystic...... fibrosis (last search May 2008). SELECTION CRITERIA: Randomised trials (published or unpublished) comparing Pseudomonas aeruginosa vaccines (oral, parenteral or intranasal) with control vaccines or no intervention in cystic fibrosis. DATA COLLECTION AND ANALYSIS: The authors independently selected trials...

  20. Identification and structure elucidation of a novel antifungal compound produced by Pseudomonas aeruginosa PGPR2 against Macrophomina phaseolina.

    Science.gov (United States)

    Illakkiam, Devaraj; Ponraj, Paramasivan; Shankar, Manoharan; Muthusubramanian, Shanmugam; Rajendhran, Jeyaprakash; Gunasekaran, Paramasamy

    2013-12-01

    Pseudomonas aeruginosa PGPR2 was found to protect mungbean plants from charcoal rot disease caused by Macrophomina phaseolina. Secondary metabolites from the culture supernatant of P. aeruginosa PGPR2 were extracted with ethyl acetate and the antifungal compound was purified by preparative HPLC using reverse phase chromatography. The purified compound showed antifungal activity against M. phaseolina and other phytopathogenic fungi (Fusarium sp., Rhizoctonia sp. Alternaria sp., and Aspergillus sp.). The structure of the purified compound was determined using (1)H, (13)C, 2D NMR spectra and liquid chromatography-mass spectrometry (LC-MS). Spectral data suggest that the antifungal compound is 3,4-dihydroxy-N-methyl-4-(4-oxochroman-2-yl)butanamide, with the chemical formula C14H17NO5 and a molecular mass of 279. Though chemically synthesized chromanone derivatives have been shown to have antifungal activity, we report for the first time, the microbial production of a chromanone derivative with antifungal activity. This ability of P. aeruginosa PGPR2 makes it a suitable strain for biocontrol.

  1. Biotransformation of myrcene by Pseudomonas aeruginosa

    Directory of Open Access Journals (Sweden)

    Hashemi Elham

    2011-05-01

    Full Text Available Abstract Background Dihydrolinalool and terpineol are sources of fragrances that provide a unique volatile terpenoid alcohol of low toxicity and thus are widely used in the perfumery industry, in folk medicine, and in aromatherapy. They are important chemical constituents of the essential oil of many plants. Previous studies have concerned the biotransformation of limonene by Pseudomonas putida. The objective of this research was to study biotransformation of myrcene by Pseudomonas aeruginosa. The culture preparation was done using such variables as different microbial methods and incubation periods to obtain maximum cells of P. aeruginosa for myrcene biotransformation. Results It was found that myrcene was converted to dihydrolinalool and 2,6-dimethyloctane in high percentages. The biotransformation products were identified by Fourier-transform infrared spectroscopy (FT-IR, ultraviolet (UV analysis, gas chromatography (GC, and gas chromatography-mass spectroscopy (GC-MS. Comparison of the different incubation times showed that 3 days was more effective, the major products being 2,6-dimethyloctane (90.0% and α-terpineol (7.7% and comprising 97.7%. In contrast, the main compounds derived for an incubation time of 1.5 days were dihydrolinalool (79.5% and 2,6-dimethyloctane (9.3%, with a total yield of 88.8%.

  2. Growth of Pseudomonas spp. in cottage cheese

    DEFF Research Database (Denmark)

    Østergaard, Nina Bjerre; Dalgaard, Paw

    Cottage cheese is a mixture of cheese curd with pH 4.5-4.8 and an uncultured or cultured cream dressing with a pH as high as 7.0. This results in a final product with microenvironments and a bulk pH of about 4.8 to 5.5. As for other lightly preserved foods microbial contamination and growth...... of spoilage microorganisms in cottage cheese can cause undesirable alterations in flavour, odour, appearance and texture. Contamination and growth of psychrotolerant pseudomonads including Pseudomonas fragi and Pseudomonas putida has been reported for cottage cheese but the influence of these bacteria......H (4.9-7.0) on growth was quantified using automated absorbance measurements (Bioscreen C). A pronounced reduction of the maximum specific growth rate was observed at pH 4.9 but at pH 5.2 strains grew at 5˚C, 10˚C and 15˚C. Challenge tests at 5-15˚C with cottage cheese (pH 5.2-5.5), and cream dressing...

  3. Ethylene glycol metabolism by Pseudomonas putida.

    Science.gov (United States)

    Mückschel, Björn; Simon, Oliver; Klebensberger, Janosch; Graf, Nadja; Rosche, Bettina; Altenbuchner, Josef; Pfannstiel, Jens; Huber, Armin; Hauer, Bernhard

    2012-12-01

    In this study, we investigated the metabolism of ethylene glycol in the Pseudomonas putida strains KT2440 and JM37 by employing growth and bioconversion experiments, directed mutagenesis, and proteome analysis. We found that strain JM37 grew rapidly with ethylene glycol as a sole source of carbon and energy, while strain KT2440 did not grow within 2 days of incubation under the same conditions. However, bioconversion experiments revealed metabolism of ethylene glycol by both strains, with the temporal accumulation of glycolic acid and glyoxylic acid for strain KT2440. This accumulation was further increased by targeted mutagenesis. The key enzymes and specific differences between the two strains were identified by comparative proteomics. In P. putida JM37, tartronate semialdehyde synthase (Gcl), malate synthase (GlcB), and isocitrate lyase (AceA) were found to be induced in the presence of ethylene glycol or glyoxylic acid. Under the same conditions, strain KT2440 showed induction of AceA only. Despite this difference, the two strains were found to use similar periplasmic dehydrogenases for the initial oxidation step of ethylene glycol, namely, the two redundant pyrroloquinoline quinone (PQQ)-dependent enzymes PedE and PedH. From these results we constructed a new pathway for the metabolism of ethylene glycol in P. putida. Furthermore, we conclude that Pseudomonas putida might serve as a useful platform from which to establish a whole-cell biocatalyst for the production of glyoxylic acid from ethylene glycol.

  4. Review: Lipopolysaccharide biosynthesis in Pseudomonas aeruginosa.

    Science.gov (United States)

    King, Jerry D; Kocíncová, Dana; Westman, Erin L; Lam, Joseph S

    2009-10-01

    Pseudomonas aeruginosa causes serious nosocomial infections, and an important virulence factor produced by this organism is lipopolysaccharide (LPS). This review summarizes knowledge about biosynthesis of all three structural domains of LPS - lipid A, core oligosaccharide, and O polysaccharides. In addition, based on similarities with other bacterial species, this review proposes new hypothetical pathways for unstudied steps in the biosynthesis of P. aeruginosa LPS. Lipid A biosynthesis is discussed in relation to Escherichia coli and Salmonella, and the biosyntheses of core sugar precursors and core oligosaccharide are summarised. Pseudomonas aeruginosa attaches a Common Polysaccharide Antigen and O-Specific Antigen polysaccharides to lipid A-core. Both forms of O polysaccharide are discussed with respect to their independent synthesis mechanisms. Recent advances in understanding O-polysaccharide biosynthesis since the last major review on this subject, published nearly a decade ago, are highlighted. Since P. aeruginosa O polysaccharides contain unusual sugars, sugar-nucleotide biosynthesis pathways are reviewed in detail. Knowledge derived from detailed studies in the O5, O6 and O11 serotypes is applied to predict biosynthesis pathways of sugars in poorly-studied serotypes, especially O1, O4, and O13/O14. Although further work is required, a full understanding of LPS biosynthesis in P. aeruginosa is almost within reach.

  5. Roseomonas terrae sp. nov.

    Science.gov (United States)

    Yoon, Jung-Hoon; Kang, So-Jung; Oh, Hyun Woo; Oh, Tae-Kwang

    2007-11-01

    A Gram-negative, non-motile, coccobacilli-shaped bacterium, DS-48T, was isolated from soil from Dokdo, Korea, and its taxonomic position was investigated by means of a polyphasic study. Strain DS-48T grew optimally at 25 degrees C and pH 7.0-8.0 in the presence of 0.5% (w/v) NaCl. It contained Q-10 as the predominant ubiquinone and C18:1omega7c and C18:1 2-OH as the major fatty acids. The DNA G+C content was 69.3 mol%. A phylogenetic analysis based on 16S rRNA gene sequences showed that strain DS-48T fell within the genus Roseomonas, clustering with Roseomonas lacus TH-G33T (at a bootstrap confidence level of 100%). The levels of similarity between the 16S rRNA gene sequence of strain DS-48T and those of the type strains of recognized Roseomonas species were in the range 93.2-98.0%. DNA-DNA relatedness data and differential phenotypic properties, together with the phylogenetic distinctiveness of DS-48T, revealed that this strain differs from recognized Roseomonas species. On the basis of phenotypic, phylogenetic and genetic data, therefore, strain DS-48T represents a novel species within the genus Roseomonas, for which the name Roseomonas terrae sp. nov. is proposed. The type strain is DS-48T (=KCTC 12874T=JCM 14592T).

  6. Bradysia sp. em morangueiro Bradysia sp. in strawberry

    Directory of Open Access Journals (Sweden)

    Bernadete Radin

    2009-04-01

    Full Text Available No trabalho, relatam-se os primeiros registros de Bradysia sp. (Insecta: Diptera: Sciaridae em morangueiro (Fragaria x ananassa Duch., cultivado no Município de Eldorado do Sul, RS. O cultivo foi realizado em sacolas com três metros de comprimento, preenchidas com substrato composto de casca de arroz e turfa, dispostas horizontalmente sobre bancadas de madeira, em ambiente protegido. A presença de Bradysia sp. foi observada na segunda quinzena de agosto de 2005. Neste trabalho, estão descritos os sintomas apresentados no morangueiro pela praga, prováveis conseqüências sobre o aparecimento de doenças e uma breve descrição morfológica da Bradysia sp., adulto e fase larval.This paper describes the first record of Bradysia sp. (Insecta; Diptera; Sciaridae in strawberry (Fragaria x ananassa, cultivated in the city of Eldorado do Sul, RS, Brazil. Strawberry was planted in plastic bags filled with a mixture of burnt rice hulls and peat and cultivated in a greenhouse. The presence of Bradysia sp was noticed in the second fortnight of August, 2005. The symptoms in strawberry and the probable consequences in terms of disease arising were described in the present study, as well as the morphological characterization of Bradysia sp. and its illustrations.

  7. Crude oil biodegradation aided by biosurfactants from Pseudozyma sp. NII 08165 or its culture broth.

    Science.gov (United States)

    Sajna, Kuttuvan Valappil; Sukumaran, Rajeev Kumar; Gottumukkala, Lalitha Devi; Pandey, Ashok

    2015-09-01

    The aim of this work was to evaluate the biosurfactants produced by the yeast Pseudozyma sp. NII 08165 for enhancing the degradation of crude oil by a model hydrocarbon degrading strain, Pseudomonas putida MTCC 1194. Pseudozyma biosurfactants were supplemented at various concentrations to the P. putida culture medium containing crude oil as sole carbon source. Supplementation of the biosurfactants enhanced the degradation of crude oil by P. putida; the maximum degradation of hydrocarbons was observed with a 2.5 mg L(-1) supplementation of biosurfactants. Growth inhibition constant of the Pseudozyma biosurfactants was 11.07 mg L(-1). It was interesting to note that Pseudozyma sp. NII 08165 alone could also degrade diesel and kerosene. Culture broth of Pseudozyma containing biosurfactants resulted up to ∼46% improvement in degradation of C10-C24 alkanes by P. putida. The enhancement in degradation efficiency of the bacterium with the culture broth supplementation was even more pronounced than that with relatively purer biosurfactants.

  8. Actinoplanes couchii sp. nov.

    Science.gov (United States)

    Kämpfer, Peter; Huber, Birgit; Thummes, Kathrin; Grün-Wollny, Iris; Busse, Hans-Jürgen

    2007-04-01

    A Gram-positive bacterium, strain GW8-1761(T), was isolated from soil close to the Marmore waterfalls, Terni, Italy. 16S rRNA gene sequence similarity studies showed that strain GW8-1761(T) belonged to the genus Actinoplanes, being most closely related to Actinoplanes italicus JCM 3165(T) (98.9 %), A. rectilineatus IFO 13941(T) (98.5 %), A. palleronii JCM 7626(T) (97.8 %), A. utahensis IFO 13244(T) (97.6 %) and A. cyaneus DSM 46137(T) (97.6 %). Strain GW8-1761(T) could be distinguished from any other Actinoplanes species with validly published names by 16S rRNA gene sequence similarity values of less than 97.5 %. Chemotaxonomic data [major menaquinone MK-9(H(4)); major polar lipids diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol, with phosphatidylcholine and aminoglycolipids absent; major fatty acids C(15 : 0), C(16 : 0), C(16 : 0) iso, C(17 : 1)omega8c and summed feature 3 (C(16 : 1)omega7c and/or C(15 : 0) iso 2-OH)] supported the affiliation of strain GW8-1761(T) to the genus Actinoplanes. The results of DNA-DNA hybridizations and physiological and biochemical tests allowed genotypic and phenotypic differentiation of strain GW8-1761(T) from the most closely related species. Strain GW8-1761(T) therefore merits species status, and we propose the name Actinoplanes couchii sp. nov., with the type strain GW8-1761(T) (=DSM 45050(T)=CIP 109316(T)).

  9. Arcobacter marinus sp. nov.

    Science.gov (United States)

    Kim, Hye Min; Hwang, Chung Yeon; Cho, Byung Cheol

    2010-03-01

    A slightly curved, rod-shaped marine bacterium, designated strain CL-S1(T), was isolated from near Dokdo, an island in the East Sea, Korea. Cells were Gram-negative and grew well under either aerobic or microaerobic conditions. Analyses of the 16S rRNA and gyrA gene sequences of strain CL-S1(T) revealed an affiliation with the genus Arcobacter within the class Epsilonproteobacteria. Phylogenetic analyses based on 16S rRNA and gyrA gene sequences showed that strain CL-S1(T) formed a robust clade with Arcobacter halophilus LA31B(T), with sequence similarities of 96.1 and 88.2 %, respectively. DNA-DNA relatedness between strain CL-S1(T) and A. halophilus DSM 18005(T) was 44 %, indicating that they represent genomically distinct species. Strain CL-S1(T) grew optimally at 30-37 degrees C, at pH 7 and in the presence of 3-5 % NaCl. The dominant cellular fatty acids were iso-C(15 : 0) 2-OH and/or C(16 : 1)omega7c (28.4 %), C(16 : 0) (26.2 %) and C(18 : 1)omega7c (22.3 %). The DNA G+C content of strain CL-S1(T) was 28 mol%. Strain CL-S1(T) differed phenotypically from A. halophilus LA31B(T) based on its ability to grow aerobically at 10 degrees C and inability to grow under anaerobic conditions. Based on the data presented, strain CL-S1(T) is considered to represent a novel species of the genus Arcobacter, for which the name Arcobacter marinus sp. nov. is proposed. The type strain is CL-S1(T) (=KCCM 90072(T) =JCM 15502(T)).

  10. Vaccines for preventing infection with Pseudomonas aeruginosa in cystic fibrosis

    DEFF Research Database (Denmark)

    Johansen, Helle Krogh; Gøtzsche, Peter C

    2015-01-01

    BACKGROUND: Chronic pulmonary infection in cystic fibrosis results in progressive lung damage. Once colonisation of the lungs with Pseudomonas aeruginosa occurs, it is almost impossible to eradicate. Vaccines, aimed at reducing infection with Pseudomonas aeruginosa, have been developed. This is a......BACKGROUND: Chronic pulmonary infection in cystic fibrosis results in progressive lung damage. Once colonisation of the lungs with Pseudomonas aeruginosa occurs, it is almost impossible to eradicate. Vaccines, aimed at reducing infection with Pseudomonas aeruginosa, have been developed....... This is an update of a previously published review. OBJECTIVES: To assess the effectiveness of vaccination against Pseudomonas aeruginosa in cystic fibrosis. SEARCH METHODS: We searched the Cochrane Cystic Fibrosis and Genetic Disorders Group Trials Register using the terms vaccines AND pseudomonas (last search 30...... March 2015). We previously searched PubMed using the terms vaccin* AND cystic fibrosis (last search 30 May 2013). SELECTION CRITERIA: Randomised trials (published or unpublished) comparing Pseudomonas aeruginosa vaccines (oral, parenteral or intranasal) with control vaccines or no intervention in cystic...

  11. Bacterial Feeders, the Nematode Caenorhabditis elegans and the Flagellate Cercomonas longicauda, have different Effects on Outcome of Competition among the Pseudomonas Biocontrol Strains CHA0 and DSS73

    DEFF Research Database (Denmark)

    Pedersen, Annette; Nybroe, Ole; Winding, Anne;

    2009-01-01

    selective feeding flagellate Cercomonas longicauda versus the non-selective feeding nematode Caenorhabditis elegans) influence the abundance of two bacteria that compete for resources in simple model communities. Microcosms consisted of either one gfp-tagged bacterial strain (Pseudomonas fluorescens DSM......50090 or one of two biocontrol strains P. fluorescens CHA0 or Pseudomonas sp. DSS73) or combinations of two bacterial strains. DSM50090 is a suitable food bacterium, DSS73 is of intermediate food quality, and CHA0 is inedible to the bacterial feeders. Bacterial and protozoan cell numbers were measured......How bacterial feeding fauna affects colonization and survival of bacteria in soil is not well understood, which constrains the applicability of bacterial inoculants in agriculture. This study aimed to unravel how food quality of bacteria and bacterial feeders with different feeding habits (the...

  12. Organization and regulation of meta cleavage pathway genes for toluene and o-xylene derivative degradation in Pseudomonas stutzeri OX1.

    Science.gov (United States)

    Arenghi, F L; Berlanda, D; Galli, E; Sello, G; Barbieri, P

    2001-07-01

    Pseudomonas stutzeri OX1 meta pathway genes for toluene and o-xylene catabolism were analyzed, and loci encoding phenol hydroxylase, catechol 2,3-dioxygenase, 2-hydroxymuconate semialdehyde dehydrogenase, and 2-hydroxymuconate semialdehyde hydrolase were mapped. Phenol hydroxylase converted a broad range of substrates, as it was also able to transform the nongrowth substrates 2,4-dimethylphenol and 2,5-dimethylphenol into 3,5-dimethylcatechol and 3,6-dimethylcatechol, respectively, which, however, were not cleaved by catechol 2,3-dioxygenase. The identified gene cluster displayed a gene order similar to that of the Pseudomonas sp. strain CF600 dmp operon for phenol catabolism and was found to be coregulated by the tou operon activator TouR. A hypothesis about the evolution of the toluene and o-xylene catabolic pathway in P. stutzeri OX1 is discussed.

  13. Surfactant protein (SP)-A and SP-D as antimicrobial and immunotherapeutic agents.

    Science.gov (United States)

    Awasthi, Shanjana

    2010-06-01

    Surfactant protein (SP)-A and SP-D belong to the "Soluble C-type Lectin" family of proteins and are collectively known as "Collectins". Based on their ability to recognize pathogens and to regulate the host defense, SP-A and SP-D have been recently categorized as "Secretory Pathogen Recognition Receptors". SP-A and SP-D were first identified in the lung; the expression of SP-A and SP-D has also been observed at other mucosal surfaces, such as lacrimal glands, gastrointestinal mucosa, genitourinary epithelium and periodontal surfaces. Since the role of these proteins is not fully elucidated at other mucosal surfaces, the focus of this article is on lung-SP-A and SP-D. It has become clear from research studies performed over a number of years that SP-A and SP-D are critical for the maintenance of lung homeostasis and the regulation of host defense and inflammation. However, none of the surfactant preparations available for clinical use have SP-A or SP-D. A review is presented here on SP-A- and SP-D-deficiencies in lung diseases, the importance of the administration of SP-A and SP-D, and recent patents and research directions that may lead to the design of novel SP-A- or SP-D-based therapeutics and surfactants.

  14. Penicillium araracuarense sp. nov., Penicillium elleniae sp. nov., Penicillium penarojense sp. nov., Penicillium vanderhammenii sp. nov. and Penicillium wotroi sp. nov., isolated from leaf litter

    DEFF Research Database (Denmark)

    Houbraken, Jos; López-Quintero, Carlos A.; Frisvad, Jens Christian

    2011-01-01

    Several species of the genus Penicillium were isolated during a survey of the mycobiota of leaf litter and soil in Colombian Amazon forest. Five species, Penicillium penarojense sp. nov. (type strain CBS 113178T = IBT 23262T), Penicillium wotroi sp. nov. (type strain CBS 118171T = IBT 23253T...

  15. Functional bacterial amyloid increases Pseudomonas biofilm hydrophobicity and stiffness

    DEFF Research Database (Denmark)

    Zeng, Guanghong; Vad, Brian Stougaard; Dueholm, Morten Simonsen

    2015-01-01

    The success of Pseudomonas species as opportunistic pathogens derives in great part from their ability to form stable biofilms that offer protection against chemical and mechanical attack. The extracellular matrix of biofilms contains numerous biomolecules, and it has recently been discovered...... that in Pseudomonas one of the components includes β-sheet rich amyloid fibrils (functional amyloid) produced by the fap operon. However, the role of the functional amyloid within the biofilm has not yet been investigated in detail. Here we investigate how the fap-based amyloid produced by Pseudomonas affects biofilm...

  16. Stratified growth in Pseudomonas aeruginosa biofilms

    DEFF Research Database (Denmark)

    Werner, E.; Roe, F.; Bugnicourt, A.;

    2004-01-01

    In this study, stratified patterns of protein synthesis and growth were demonstrated in Pseudomonas aeruginosa biofilms. Spatial patterns of protein synthetic activity inside biofilms were characterized by the use of two green fluorescent protein (GFP) reporter gene constructs. One construct...... carried an isopropyl-beta-D-thiogalactopyranoside (IPTG)-inducible gfpmut2 gene encoding a stable GFP. The second construct carried a GFP derivative, gfp-AGA, encoding an unstable GFP under the control of the growth-rate-dependent rrnBp(1) promoter. Both GFP reporters indicated that active protein...... of oxygen limitation in the biofilm. Oxygen microelectrode measurements showed that oxygen only penetrated approximately 50 mum into the biofilm. P. aeruginosa was incapable of anaerobic growth in the medium used for this investigation. These results show that while mature P. aeruginosa biofilms contain...

  17. Complement activation by Pseudomonas aeruginosa biofilms

    DEFF Research Database (Denmark)

    Jensen, E T; Kharazmi, A; Garred, P

    1993-01-01

    In chronic infections, such as the bronchopulmonary Pseudomonas aeruginosa infection in cystic fibrosis (CF) patients, bacteria persist despite an intact host immune defense and frequent antibiotic treatment. An important reason for the persistence of the bacteria is their capacity for the biofilm...... mode of growth. In this study we investigated the role of biofilms in activation of complement, a major contributor to the inflammatory process. Complement activation by P. aeruginosa was examined in a complement consumption assay, production of C3 and factor B conversion products assessed by crossed...... immuno-electrophoresis, C5a generation tested by a PMN chemotactic assay, and terminal complement complex formation measured by ELISA. Two of the four assays showed that P. aeruginosa grown in biofilm activated complement less than planktonic bacteria, and all assays showed that activation by intact...

  18. Pseudomonas aeruginosa endophthalmitis masquerading as chronic uveitis

    Directory of Open Access Journals (Sweden)

    Kalpana Badami Nagaraj

    2013-01-01

    Full Text Available A 65-year-old male presented with decreased vision in the left eye of 15-day duration after having undergone an uneventful cataract surgery 10 months back. He had been previously treated with systemic steroids for recurrent uveitis postoperatively on three occasions in the same eye. B-scan ultrasonography showed multiple clumplike echoes suggestive of vitreous inflammation. Aqueous tap revealed Pseudomonas aeruginosa sensitive to ciprofloxacin. The patient was treated with intravitreal ciprofloxacin and vancomycin along with systemic ciprofloxacin with good clinical response. Even a virulent organism such as P.aeruginosa can present as a chronic uveitis, which, if missed, can lead to a delay in accurate diagnosis and appropriate management.

  19. The immune system vs. Pseudomonas aeruginosa biofilms

    DEFF Research Database (Denmark)

    Jensen, Peter Østrup; Givskov, Michael; Bjarnsholt, Thomas

    2010-01-01

    revealed both innate as well as adaptive immune responses to biofilms. On the other hand, measures launched by biofilm bacteria to achieve protection against the various immune responses have also been demonstrated. Whether particular immune responses to biofilm infections exist remains to be firmly...... established. However, because biofilm infections are often persistent (or chronic), an odd situation appears with the simultaneous activation of both arms of the host immune response, neither of which can eliminate the biofilm pathogen, but instead, in synergy, causes collateral tissue damage. Although...... the present review on the immune system vs. biofilm bacteria is focused on Pseudomonas aeruginosa (mainly because this is the most thoroughly studied), many of the same mechanisms are also seen with biofilm infections generated by other microorganisms....

  20. Glycopeptide dendrimers as Pseudomonas aeruginosa biofilm inhibitors.

    Science.gov (United States)

    Reymond, Jean-Louis; Bergmann, Myriam; Darbre, Tamis

    2013-06-01

    Synthetic glycopeptide dendrimers composed of a branched oligopeptide tree structure appended with glycosidic groups at its multiple N-termini were investigated for binding to the Pseudomonas aeruginosa lectins LecB and LecA. These lectins are partly responsible for the formation of antibiotic resistant biofilms in the human pathogenic bacterium P. aeruginosa, which causes lethal airway infections in immune-compromised and cystic fibrosis patients. Glycopeptide dendrimers with high affinity to the lectins were identified by screening of combinatorial libraries. Several of these dendrimers, in particular the LecB specific glycopeptide dendrimers FD2 and D-FD2 and the LecA specific glycopeptide dendrimers GalAG2 and GalBG2, also efficiently block P. aeruginosa biofilm formation and induce biofilm dispersal in vitro. Structure-activity relationship and structural studies are reviewed, in particular the observation that multivalency is essential to the anti-biofilm effect in these dendrimers.

  1. Pseudomonas aeruginosa biofilms in cystic fibrosis

    DEFF Research Database (Denmark)

    Høiby, Niels; Ciofu, Oana; Bjarnsholt, Thomas

    2010-01-01

    The persistence of chronic Pseudomonas aeruginosa lung infections in cystic fibrosis (CF) patients is due to biofilm-growing mucoid (alginate-producing) strains. A biofilm is a structured consortium of bacteria, embedded in a self-produced polymer matrix consisting of polysaccharide, protein...... and DNA. In CF lungs, the polysaccharide alginate is the major part of the P. aeruginosa biofilm matrix. Bacterial biofilms cause chronic infections because they show increased tolerance to antibiotics and resist phagocytosis, as well as other components of the innate and the adaptive immune system....... As a consequence, a pronounced antibody response develops, leading to immune complex-mediated chronic inflammation, dominated by polymorphonuclear leukocytes. The chronic inflammation is the major cause of the lung tissue damage in CF. Biofilm growth in CF lungs is associated with an increased frequency...

  2. Occurrence of Pseudomonas aeruginosa in Kuwait soil.

    Science.gov (United States)

    Al-Saleh, Esmaeil; Akbar, Abrar

    2015-02-01

    Environmentally ubiquitous bacteria such as Pseudomonas aeruginosa evolved mechanisms to adapt and prevail under diverse conditions. In the current investigation, strains of P. aeruginosa demonstrating high rates of crude oil utilization and tolerance to high concentrations of heavy metals were found in both crude oil-contaminated and uncontaminated sites in Kuwait, and were dominant in the contaminated sites. The incidence of P. aeruginosa in tested soils implies the definitive pattern of crude oil contamination in the selection of the bacterial population in petroleum-contaminated sites in Kuwait. Surprisingly, the unculturable P. aeruginosa in different soil samples showed significant high similarity coefficients based on 16S-RFLP analyses, implying that the unculturable fraction of existing bacterial population in environmental samples is more stable and, hence, reliable for phylogenetic studies compared to the culturable bacteria.

  3. Osmoregulation in Pseudomonas aeruginosa under hyperosmotic shock.

    Science.gov (United States)

    Velasco, R; Burgoa, R; Flores, E; Hernández, E; Villa, A; Vaca, S

    1995-01-01

    Pseudomonas aeruginosa PAO1 strain was found to be able to tolerate 700 mM NaCl. 0.5 mM of the osmoprotectant betaine restablished the growth of this strain in 1200 mM NaCl. Intracellular K+ and glutamate concentrations of P. aeruginosa PAO1 after an hyperosmotic shock (400 mM NaCl) showed a permanent increase. Adition of betaine (0.5 mM) to the medium with NaCl had an inhibitory effect on the intracellular accumulation of glutamate. The results indicate that P. aeruginosa PAO1 resists high NaCl concentrations, K+ accumulation and glutamate synthesis probably being the first mechanisms involved in adaptation to osmotic stress. Also is is demonstrated that betaine modulates intracellular glutamate levels in osmotically stressed P. aeruginosa PAO1.

  4. Rhamnolipid Biosurfactants Produced by Pseudomonas Species

    Directory of Open Access Journals (Sweden)

    Banu Kaskatepe

    Full Text Available ABSTRACT: Surfactants are chemical products widely used in our daily life in toothpaste and other personal hygiene and cosmetic products, and in several industries. Biosurfactants are surfactants of biological origin that can be produced by microorganisms and have many advantages, such as low toxicity and high biodegradability, compared to synthetic counterparts. Unfortunately, high production costs limit the use of biosurfactants. Low-cost production is the most important factor for biosurfactants to be able to compete in the global market place. This review presents general information on rhamnolipid biosurfactant produced by Pseudomonas species, as well as on their production and applications. In addition, industrial products and their wastes used for rhamnolipid production are reviewed in detail based on recent studies.

  5. Vesiculation from Pseudomonas aeruginosa under SOS

    Directory of Open Access Journals (Sweden)

    Reshma Maredia

    2012-01-01

    Full Text Available Bacterial infections can be aggravated by antibiotic treatment that induces SOS response and vesiculation. This leads to a hypothesis concerning association of SOS with vesiculation. To test it, we conducted multiple analyses of outer membrane vesicles (OMVs produced from the Pseudomonas aeruginosa wild type in which SOS is induced by ciprofloxacin and from the LexA noncleavable (lexAN strain in which SOS is repressed. The levels of OMV proteins, lipids, and cytotoxicity increased for both the treated strains, demonstrating vesiculation stimulation by the antibiotic treatment. However, the further increase was suppressed in the lexAN strains, suggesting the SOS involvement. Obviously, the stimulated vesiculation is attributed by both SOS-related and unrelated factors. OMV subproteomic analysis was performed to examine these factors, which reflected the OMV-mediated cytotoxicity and the physiology of the vesiculating cells under treatment and SOS. Thus, SOS plays a role in the vesiculation stimulation that contributes to cytotoxicity.

  6. Description of Pelomonas aquatica sp. nov. and Pelomonas puraquae sp. nov., isolated from industrial and haemodialysis water.

    Science.gov (United States)

    Gomila, Margarita; Bowien, Botho; Falsen, Enevold; Moore, Edward R B; Lalucat, Jorge

    2007-11-01

    Three Gram-negative, rod-shaped, non-spore-forming bacteria (strains CCUG 52769T, CCUG 52770 and CCUG 52771) isolated from haemodialysis water were characterized taxonomically, together with five strains isolated from industrial waters (CCUG 52428, CCUG 52507, CCUG 52575T, CCUG 52590 and CCUG 52631). Phylogenetic analysis based on 16S rRNA gene sequences indicated that these isolates belonged to the class Betaproteobacteria and were related to the genus Pelomonas, with 16S rRNA gene sequence similarities higher than 99% with the only species of the genus, Pelomonas saccharophila and to Pseudomonas sp. DSM 2583. The type strains of Mitsuaria chitosanitabida and Roseateles depolymerans were their closest neighbours (97.9 and 97.3% 16S rRNA gene sequence similarity, respectively). Phylogenetic analysis was also performed for the internally transcribed spacer region and for three genes [hoxG (hydrogenase), cbbL/cbbM (Rubisco) and nifH (nitrogenase)] relevant for the metabolism of the genus Pelomonas. DNA-DNA hybridization, major fatty acid composition and phenotypical analyses were carried out, which included the type strain of Pelomonas saccharophila obtained from different culture collections (ATCC 15946T, CCUG 32988T, DSM 654T, IAM 14368T and LMG 2256T), as well as M. chitosanitabida IAM 14711T and R. depolymerans CCUG 52219T. Results of DNA-DNA hybridization, physiological and biochemical tests supported the conclusion that strains CCUG 52769, CCUG 52770 and CCUG 52771 represent a homogeneous phylogenetic and genomic group, including strain DSM 2583, clearly differentiated from the industrial water isolates and from the Pelomonas saccharophila type strain. On the basis of phenotypic and genotypic characteristics, these strains belong to two novel species within the genus Pelomonas, for which the names Pelomonas puraquae sp. nov. and Pelomonas aquatica sp. nov. are proposed. The type strains of Pelomonas puraquae sp. nov. and Pelomonas aquatica sp. nov. are CCUG

  7. Generalized λ-deformations of AdSp × Sp

    Science.gov (United States)

    Chervonyi, Yuri; Lunin, Oleg

    2016-12-01

    We study analytical properties of the generalized λ-deformation, which modifies string theories while preserving integrability, and construct the explicit backgrounds corresponding to AdSp ×Sp, including the Ramond-Ramond fluxes. For an arbitrary coset, we find the general form of the R-matrix underlying the deformation, and prove that the dilaton is not modified by the deformation, while the frames are multiplied by a constant matrix. Our explicit solutions describe families of integrable string theories depending on several continuous parameters.

  8. Caenorhabditis elegans reveals novel Pseudomonas aeruginosa virulence mechanism

    NARCIS (Netherlands)

    Utari, Putri Dwi; Quax, Wim J.

    2013-01-01

    The susceptibility of Caenorhabditis elegans to different virulent phenotypes of Pseudomonas aeruginosa makes the worms an excellent model for studying host-pathogen interactions. Including the recently described liquid killing, five different killing assays are now available offering superb possibi

  9. Caenorhabditis elegans reveals novel Pseudomonas aeruginosa virulence mechanism

    NARCIS (Netherlands)

    Utari, Putri Dwi; Quax, Wim J.

    2013-01-01

    The susceptibility of Caenorhabditis elegans to different virulent phenotypes of Pseudomonas aeruginosa makes the worms an excellent model for studying host-pathogen interactions. Including the recently described liquid killing, five different killing assays are now available offering superb possibi

  10. Pseudomonas aeruginosa Dose-Response and Bathing Water Infection

    Science.gov (United States)

    Pseudomonas aeruginosa is the most commonly identified opportunistic pathogen associated with pool acquired bather disease. To better understand why this microorganism poses this protracted problem we recently appraised P. aeruginosa pool risk management. Much is known about the ...

  11. The Enzymes of the Ammonia Assimilation in Pseudomonas aeruginosa

    NARCIS (Netherlands)

    Janssen, Dick B.; Camp, Huub J.M. op den; Leenen, Pieter J.M.; Drift, Chris van der

    1980-01-01

    Glutamine synthetase from Pseudomonas aeruginosa is regulated by repression/derepression of enzyme synthesis and by adenylylation/deadenylylation control. High levels of deadenylylated biosynthetically active glutamine synthetase were observed in cultures growing with limiting amounts of nitrogen wh

  12. Outbreak of Pseudomonas aeruginosa bacteraemia in a haematology department

    DEFF Research Database (Denmark)

    Rasmussen, Benjamin Schnack; Christensen, Nikolas; Sørensen, Jan;

    2015-01-01

    INTRODUCTION: Infection by Pseudomonas aeruginosa represents a major cause of morbidity and mortality among immunocompromised patients. In Denmark, an increase in P. aeruginosa isolates from blood cultures from a haematology department prompted a hygienic audit in 2007. METHODS: Blood cultures...

  13. Effect of biosurfactant from two strains of Pseudomonas on ...

    African Journals Online (AJOL)

    PRECIOUS

    2009-12-01

    Dec 1, 2009 ... Two Pseudomonas strains isolated from oil-contaminated soil which produce biosurfactant were studied. .... Refinery, Assam, India, each having a varied level of oil conta- mination. ..... Rapid method for monitoring maximum.

  14. Novel Targets for Treatment of Pseudomonas aeruginosa Biofilms

    DEFF Research Database (Denmark)

    Alhede, Morten; Alhede, Maria; Bjarnsholt, Thomas

    2014-01-01

    Pseudomonas aeruginosa causes infection in all parts of the human body. The bacterium is naturally resistant to a wide range of antibiotics. In addition to resistance mechanisms such as efflux pumps, the ability to form aggregates, known as biofilm, further reduces Pseudomonas aeruginosa’s suscep......Pseudomonas aeruginosa causes infection in all parts of the human body. The bacterium is naturally resistant to a wide range of antibiotics. In addition to resistance mechanisms such as efflux pumps, the ability to form aggregates, known as biofilm, further reduces Pseudomonas aeruginosa......’s susceptibility to antibiotics. The presence of such biofilms is acknowledged to equal a persistent infection due to their inherent high tolerance to all antimicrobials and immune cells. In this chapter we discuss the mechanisms of biofilm tolerance. The latest biofilm research is reviewed and future treatment...

  15. Pseudomonas Folliculitis Associated with Use of Hot Tubs and Spas.

    Science.gov (United States)

    Ramsey, Michael L.

    1989-01-01

    Discusses the history, etiology, diagnosis, histopathology, treatment, and prevention of Pseudomonas Folliculitis, an increasingly common skin infection contracted in hot tubs and, to some extent, in swimming pools. (Author/SM)

  16. The Enzymes of the Ammonia Assimilation in Pseudomonas aeruginosa

    NARCIS (Netherlands)

    Janssen, Dick B.; Camp, Huub J.M. op den; Leenen, Pieter J.M.; Drift, Chris van der

    1980-01-01

    Glutamine synthetase from Pseudomonas aeruginosa is regulated by repression/derepression of enzyme synthesis and by adenylylation/deadenylylation control. High levels of deadenylylated biosynthetically active glutamine synthetase were observed in cultures growing with limiting amounts of nitrogen wh

  17. Isolation, purification and properties of lipase from Pseudomonas ...

    African Journals Online (AJOL)

    Isolation, purification and properties of lipase from Pseudomonas aeruginosa. ... medium agar containing Tween 80 or olive oil as the only source of carbon. ... through the purification procedure of ammonium sulphate precipitation and diethyl ...

  18. New strategies for genetic engineering Pseudomonas syringae using recombination

    Science.gov (United States)

    Here we report that DNA oligonucleotides (oligos) introduced directly into bacteria by electroporation can recombine with the bacterial chromosome. This phenomenon was identified in Pseudomonas syringae and we subsequently found that Escherichia coli, Salmonella typhimurium and Shigella flexneri are...

  19. Genetic construction of recombinant Pseudomonas chlororaphis for improved glycerol utilization

    Science.gov (United States)

    The objective of this study is to improve by genetic engineering the glycerol metabolic capability of Pseudomonas chlororaphis which is capable of producing commercially valuable biodegradable poly(hydroxyalkanoate) (PHA) and biosurfactant rhamnolipids (RLs). In the study, glycerol uptake facilitat...

  20. Characterization of Glutamine-Requiring Mutants of Pseudomonas aeruginosa

    NARCIS (Netherlands)

    Janssen, Dick B.; Joosten, Han M.L.J.; Herst, Patricia M.; Drift, Chris van der

    1982-01-01

    Revertants were isolated from a glutamine-requiring mutant of Pseudomonas aeruginosa PAO. One strain showed thermosensitive glutamine requirement and formed thermolabile glutamine synthetase, suggesting the presence of a mutation in the structural gene for glutamine synthetase. The mutation conferri

  1. Pseudomonas aeruginosa Dose-Response and Bathing Water Infection

    Science.gov (United States)

    Pseudomonas aeruginosa is the most commonly identified opportunistic pathogen associated with pool acquired bather disease. To better understand why this microorganism poses this protracted problem we recently appraised P. aeruginosa pool risk management. Much is known about the ...

  2. KEEFEKTIFAN EKSTRAK MENGKUDU PADA BERBAGAI KONSENTRASI TERHADAP PENGHAMBATAN PERTUMBUHAN BAKTERI RALSTONIA SP. SECARA IN VITRO

    Directory of Open Access Journals (Sweden)

    Efri dan Titik Nur Aeny .

    2012-02-01

    Full Text Available Effectivity of  Morinda citrifolia extract on in-vitro growth inhibition of Ralstonia sp.  Morinda citrifolia has been known as one of plants having numerous medicinal properties.  Extract of the fruits shows antibacterial activity against several bacteria including Pseudomonas aeruginosa.  The purpose of this study was to observe inhibitor effect of  M. citrifolia fruit extract, and to investigate the effect of different concentrations of  M. citrifolia fruit extract on in-vitro growth of  Ralstonia (Pseudomonas sp., the causal agent of banana bacterial wilt disease in Lampung.  Inhibition effect of  M. citrifolia was determined by the presence of inhibition zone, and concentration effect was determined by the diameter of  inhibition zone . The study consisted of two experiments.  The treatments of the first experiment were three different kinds of fruit extract, namely the whole fruit, the seeds, and the fleshy parts, and the second one consisted of six different levels of extract concentrations.  The results showed that the whole fruit extract was the most effective as an in-vitro growth inhibitor, and the higher the concentration level the higher the growth inhibition zone formed.

  3. Endophytic bacteria from Piper tuberculatum Jacq.: isolation, molecular characterization, and in vitro screening for the control of Fusarium solani f. sp piperis, the causal agent of root rot disease in black pepper (Piper nigrum L.).

    Science.gov (United States)

    Nascimento, S B; Lima, A M; Borges, B N; de Souza, C R B

    2015-07-06

    Endophytic bacteria have been found to colonize internal tissues in many different plants, where they can have several beneficial effects, including defense against pathogens. In this study, we aimed to identify endophytic bacteria associated with roots of the tropical piperaceae Piper tuberculatum, which is known for its resistance to infection by Fusarium solani f. sp piperis, the causal agent of black pepper (Piper nigrum) root rot disease in the Amazon region. Based on 16S rRNA gene sequence analysis, we isolated endophytes belonging to 13 genera: Bacillus, Paenibacillus, Pseudomonas, Enterobacter, Rhizobium, Sinorhizobium, Agrobacterium, Ralstonia, Serratia, Cupriavidus, Mitsuaria, Pantoea, and Staphylococcus. The results showed that 56.52% of isolates were associated with the phylum Proteobacteria, which comprised α, β, and γ classes. Other bacteria were related to the phylum Firmicutes, including Bacillus, which was the most abundant genus among all isolates. Antagonistic assays revealed that Pt12 and Pt13 isolates, identified as Pseudomonas putida and Pseudomonas sp, respectively, were able to inhibit F. solani f. sp piperis growth in vitro. We describe, for the first time, the molecular identification of 23 endophytic bacteria from P. tuberculatum, among which two Pseudomonas species have the potential to control the pathogen responsible for root rot disease in black pepper in the Amazon region.

  4. Antagonistic activity of antibiotic producing Streptomyces sp. against fish and human pathogenic bacteria

    Directory of Open Access Journals (Sweden)

    Nazmul Hossain

    2014-04-01

    Full Text Available In this study, attempts were made to isolate Streptomyces sp. from soil samples of two different regions of Bangladesh and evaluate their antagonistic activity against fish and human pathogenic bacteria. A total of 10 isolates were identified as Streptomyces sp. based on several morphological, physiological and biochemical tests. Cross streak method was used to observe the antagonistic activity of the Streptomyces sp. isolates against different fish pathogens belonging to the genus Aeromonas, Pseudomonas and Edwardsiella and human clinical isolates belonging to the genus Klebsiella, Salmonella and Streptococcus. Seven Streptomyces sp. isolates showed antagonism against both fish and human pathogenic bacteria. Four isolates viz., N24, N26, N28 and N47 showed broad spectrum of antagonistic activity (80-100% against all genera of fish and human pathogenic bacteria. The isolate N49 exhibited highest spectrum of antagonism against all fish pathogens (90-100% but comparatively lower degree of antagonism against human pathogens (50-60%. Rest of the two isolates (N21 and N23 showed variability in their antagonism. Results showed that broad spectrum antibiotic(s could be developed from the isolates N24, N26, N28 and N47against several human and fish pathogens. The isolate N49 could be a potential source of antibiotic, especially for fish pathogenic bacteria.

  5. Tracing of Two Pseudomonas Strains in the Root and Rhizoplane of Maize, as Related to Their Plant Growth-Promoting Effect in Contrasting Soils.

    Science.gov (United States)

    Mosimann, Carla; Oberhänsli, Thomas; Ziegler, Dominik; Nassal, Dinah; Kandeler, Ellen; Boller, Thomas; Mäder, Paul; Thonar, Cécile

    2016-01-01

    TaqMan-based quantitative PCR (qPCR) assays were developed to study the persistence of two well-characterized strains of plant growth-promoting rhizobacteria (PGPR), Pseudomonas fluorescens Pf153 and Pseudomonas sp. DSMZ 13134, in the root and rhizoplane of inoculated maize plants. This was performed in pot experiments with three contrasting field soils (Buus, Le Caron and DOK-M). Potential cross-reactivity of the qPCR assays was assessed with indigenous Pseudomonas and related bacterial species, which had been isolated from the rhizoplane of maize roots grown in the three soils and then characterized by Matrix-Assisted Laser Desorption Ionization (MALDI) Time-of-Flight (TOF) mass spectrometry (MS). Sensitivity of the qPCR expressed as detection limit of bacterial cells spiked into a rhizoplane matrix was 1.4 × 10(2) CFU and 1.3 × 10(4) CFU per gram root fresh weight for strain Pf153 and DSMZ 13134, respectively. Four weeks after planting and inoculation, both strains could readily be detected in root and rhizoplane, whereas only Pf153 could be detected after 8 weeks. The colonization rate of maize roots by strain Pf153 was significantly influenced by the soil type, with a higher colonization rate in the well fertile and organic soil of Buus. Inoculation with strain DSMZ 13134, which colonized roots and rhizoplane to the same degree, independently of the soil type, increased yield of maize, in terms of biomass accumulation, only in the acidic soil of Le Caron, whereas inoculation with strain Pf153 reduced yield in the soil Buus, despite of its high colonization rate and persistence. These results indicate that the colonization rate and persistence of inoculated Pseudomonas strains can be quantitatively assessed by the TaqMan-based qPCR technique, but that it cannot be taken for granted that inoculation with a well-colonizing and persistent Pseudomonas strain has a positive effect on yield of maize.

  6. Shanghai Fever: A Fatal Form of Pseudomonas Aeruginosa Enteric Disease.

    Science.gov (United States)

    Halder, Pankaj; Mandal, Kartik Chandra; Mukhopadhyay, Madhumita; Debnath, Bidyut

    2015-10-01

    Outcome of pseudomonas enteric fever is unpredictable as multiple systemic lethal complications occur abruptly. A 9-month-old girl with multiple ileal perforations, leukocoria, ecthyma gangrenosum, hemiplegia and a perforated ulcer in the soft palate. Blood culture suggested Pseudomonas aeruginosa infection. Operative repair of multiple ileal perforations and multidisciplinary management was provided. On 10th post-operative day, patient succumbed to multiple organ dysfunction syndrome. Early detection and management of complications of P. aeruginosa enteric disease is important.

  7. Spontaneous Nosocomial Pseudomonas aeruginosa Meningitis Presenting as Trismus

    OpenAIRE

    C. J. Parr; J. Wheeler; A. Sharma; Smith, C.

    2017-01-01

    We describe the case of a 78-year-old female receiving adjuvant postsurgical chemotherapy for colon adenocarcinoma who spontaneously developed nosocomial Pseudomonas meningitis causing severe trismus. The patient was initially admitted for ileus, developing neck stiffness and trismus on the thirteenth day of admission. Cerebrospinal fluid grew pansensitive Pseudomonas aeruginosa. Magnetic resonance imaging of the brain was consistent with bilateral subacute infarcts secondary to meningitis. T...

  8. Identification and characterization of peach pathogen Pseudomonas syringae

    OpenAIRE

    Gavrilović, Veljko; Dolovac, Nenad; Trkulja, Nenad; Stevanović, Miloš; Živković, Svetlana; Poštić, Dobrivoj; Ivanović, Žarko

    2011-01-01

    Pseudomonas syringae is economically important plant pathogen, found on a number of hosts including fruit trees, field crops, vegetables and decorative plants. This phytopathogenic bacteria is becoming a quite widespread pathogen on the fruit trees in Serbia, causing significant economic loses. Up to now it was experimentally confirmed as a pathogen on the pear, apple, apricot, cherry, sour cherry, plum trees as well as raspberries. In this study Pseudomonas syringae was identificated as path...

  9. QUALITY OF MINIMALLY PROCESSED YAM (Dioscorea sp. STORED AT TWO DIFFERENT TEMPERATURES

    Directory of Open Access Journals (Sweden)

    ADRIANO DO NASCIMENTO SIMÕES

    2016-01-01

    Full Text Available This work studied the physical, chemical and bio chemical alterations in minimally processed yam stored at two different temperatures, as well a s the incidence of bacteria of the genus Pseudomonas . The experimental design was completely randomised in a 2x8 factorial design, with two storage temperature s (5 and 10°C and eight storage times (0, 2, 4, 6, 8, 1 0, 12 and 14 days. Experiments were in triplicate. Yam was selected, peeled and cut into slices of approximate ly 3 cm thickness. The slices were rinsed with wate r, sanitised and then drained in kitchen strainers. Ap proximately 300 g of the processed product were pac ked in nylon multilayers 15 μ m thick, 15 cm wide and 20 cm long. The packs were sealed, weighed and kept at 5 and 10 ± 2°C for 14 days. Fresh weight loss, baking tim e, enzymatic activity of polyphenol oxidases, perox idases and catalases, total soluble phenol content, and an tioxidant capacity were evaluated, as well as visua l analysis and incidence of Pseudomonas sp. Means of temperatures were compared by Tukey ́s test at 5% significance. Yam storage at 5°C reduced weight loss and kept vis ual quality for longer; it also reduced cooking tim e and the activity of the enzymes polyphenol oxidase and pero xidase. In contrast, it promoted higher content of total soluble phenols, as well as a higher catalase activ ity and antioxidant capacity. During the storage ti me, there was no incidence of Pseudomonas sp. Minimally processed yam stored at 10°C may be sold for up to six days, and yam stored at 5ºC for up to 14 days.

  10. Factores bióticos y abióticos que condicionan la biorremediación por Pseudomonas en suelos contaminados por hidrocarburos

    OpenAIRE

    Gómez Romero, Sara Esmeralda; Gutiérrez Bustos, Diana Carolina; Hernández Marín, Ana María; Hernández Rodríguez, Cindy Zulay; Losada Casallas, Mariana; Mantilla Vargas, Paula Cecilia

    2008-01-01

    El proceso de biorremediación de hidrocarburos, contaminantes del suelo, llevado a cabo por Pseudomonas sp. está condicionado por factores bióticos y abióticos como los nutrientes, respiración, pH, humedad y temperatura propios del microorganismo, los cuales al ser modificados limitan o favorecen la capacidad metabólica de la bacteria y su adaptabilidad con el cambio de posición de los ácidos grasos de la membrana celular. La biorremediación de suelos ha demostrado ser una tecnología eficaz p...

  11. The hrpZ Gene of Pseudomonas syringae pv. phaseolicola Enhances Resistance to Rhizomania Disease in Transgenic Nicotiana benthamiana and Sugar Beet

    OpenAIRE

    Ourania I Pavli; Kelaidi, Georgia I.; Tampakaki, Anastasia P.; Skaracis,George N.

    2011-01-01

    To explore possible sources of transgenic resistance to the rhizomania-causing Beet necrotic yellow vein virus (BNYVV), Nicotiana benthamiana plants were constructed to express the harpin of Pseudomonas syringae pv. phaseolicola (HrpZ(Psph)). The HrpZ protein was expressed as an N-terminal fusion to the PR1 signal peptide (SP/HrpZ) to direct harpin accumulation to the plant apoplast. Transgene integration was verified by mPCR in all primary transformants (T0), while immunoblot analysis confir...

  12. Factores bióticos y abióticos que condicionan la biorremediación por Pseudomonas en suelos contaminados por hidrocarburos

    OpenAIRE

    Gómez Romero, Sara Esmeralda; Gutiérrez Bustos, Diana Carolina; Hernández Marín, Ana María; Hernández Rodríguez, Cindy Zulay; Losada Casallas, Mariana; Mantilla Vargas, Paula Cecilia

    2008-01-01

    El proceso de biorremediación de hidrocarburos, contaminantes del suelo, llevado a cabo por Pseudomonas sp. está condicionado por factores bióticos y abióticos como los nutrientes, respiración, pH, humedad y temperatura propios del microorganismo, los cuales al ser modificados limitan o favorecen la capacidad metabólica de la bacteria y su adaptabilidad con el cambio de posición de los ácidos grasos de la membrana celular. La biorremediación de suelos ha demostrado ser una tecnología eficaz p...

  13. Strain identification and quorum sensing inhibition characterization of marine-derived Rhizobium sp. NAO1

    Science.gov (United States)

    Chang, Hong; Zhu, Xiaoshan; Yu, Shenchen; Chen, Lu; Jin, Hui; Cai, Zhonghua

    2017-01-01

    A novel strategy for combating pathogens is through the ongoing development and use of anti-quorum sensing (QS) treatments such as therapeutic bacteria or their anti-QS substances. Relatively little is known about the bacteria that inhabit the open ocean and of their potential anti-pathogenic attributes; thus, in an initiative to identify these types of therapeutic bacteria, planktonic microbes from the North Atlantic Ocean were collected, isolated, cultured and screened for anti-QS activity. Screening analysis identified one such strain, Rhizobium sp. NAO1. Extracts of Rhizobium sp. NAO1 were identified via ultra-performance liquid chromatography (UPLC) analysis. They were shown to contain N-acyl homoserine lactone (AHL)-based QS analogues (in particular, the N-butyryl homoserine lactone (C4-AHL) analogue) and could disrupt biofilm formation by Pseudomonas aeruginosa PAO1. QS inhibition was confirmed using confocal scanning laser microscopy and growth curves, and it was shown to occur in a dose-dependent manner without affecting bacterial growth. Secondary metabolites of Rhizobium sp. NAO1 inhibited PAO1 pathogenicity by downregulating AHL-mediated virulence factors such as elastase activity and siderophore production. Furthermore, as a result of biofilm structure damage, the secondary metabolite products of Rhizobium sp. NAO1 significantly increased the sensitivity of PAO1 to aminoglycoside antibiotics. Our results demonstrated that Rhizobium sp. strain NAO1 has the ability to disrupt P. aeruginosa PAO1 biofilm architecture, in addition to attenuating P. aeruginosa PAO1 virulence factor production and pathogenicity. Therefore, the newly identified ocean-derived Rhizobium sp. NAO1 has the potential to serve as a QS inhibitor and may be a new microbial resource for drug development.

  14. Dynamics of development and dispersal in sessile microbial communities: examples from Pseudomonas aeruginosa and Pseudomonas putida model biofilms

    DEFF Research Database (Denmark)

    Klausen, M.; Gjermansen, Morten; Kreft, J.-U.;

    2006-01-01

    Surface-associated microbial communities in many cases display dynamic developmental patterns. Model biofilms formed by Pseudomonas aeruginosa and Pseudomonas putida in laboratory flow-chamber setups represent examples of such behaviour. Dependent on the experimental conditions the bacteria...... organisms do not possess comprehensive genetic programs for biofilm development. Instead the bacteria appear to have evolved a number of different mechanisms to optimize surface colonization, of which they express a subset in response to the prevailing environmental conditions. These mechanisms include...

  15. Cloning and nucleotide sequence of D-hydantoinase gene of marine polyphosphate-accumulating bacterium, Halomonas sp.YSR-3

    Institute of Scientific and Technical Information of China (English)

    REN Shiying; LI Xiangqian; JIA Jianbo; LIU Fei; XIAO Tian

    2011-01-01

    Hydantoinase is involved in the production of optically pure amino acids from racemic 5-mono-substituted hydantoions.We measured the D-hydantoinase activity in marine Halomonas sp.YSR-3 and amplified the D-hydantoinase gene by PCR.The gene was inserted into vector pGM-T and transformed into E.coli TOP 10.The positive transformants with the D-hydantoinase gene were sequenced.The sequenced fragment comprises 1510 base pairs.The D-hydantoinase gene from YSR-3 is 77% similar to that from Pseudomonas entomophila L4 by searching against the NCBI databse.The protein product of the YSR-3 D-hydantoinase gene is 75%,73%,and 70% similar to those from Pseudomonas fluorescens Pf-5,Marinomonas sp.MED121,and Burkholderia vietnamiensis G4,respectively.The difference of the D-hydantoinase gene between marine Halomonas sp.YSR-3 and other terrestrial organisms is distinct.

  16. [Mechanism of cyanide and thiocyanate decomposition by an association of Pseudomonas putida and Pseudomonas stutzeri strains].

    Science.gov (United States)

    Grigor'eva, N V; Kondrat'eva, T F; Krasil'nikova, E N; Karavaĭko, G I

    2006-01-01

    The intermediate and terminal products of cyanide and thiocyanate decomposition by individual strains of the genus Pseudomonas, P. putida strain 21 and P. stutzeri strain 18, and by their association were analyzed. The activity of the enzymes of nitrogen and sulfur metabolism in these strains was compared with that of the collection strains P. putida VKM B-2187T and P. stutzeri VKM B-975T. Upon the introduction of CN- and SCN- into cell suspensions of strains 18 and 21 in phosphate buffer (pH 8.8), the production of NH4+ was observed. Due to the high rate of their utilization, NH3, NH4+, and CNO- were absent from the culture liquids of P. putida strain 21 and P. stutzeri strain 18 grown with CN- or SCN-. Both Pseudomonas strains decomposed SCN- via cyanate production. The cyanase activity was 0.75 micromol/(min mg protein) for P. putida strain 21 and 1.26 micromol/(min mg protein) for P. stutzeri strain 18. The cyanase activity was present in the cells grown with SCN- but absent in cells grown with NH4+. Strain 21 of P. putida was a more active CN- decomposer than strain 18 of P. stutzeri. Ammonium and CO2 were the terminal nitrogen and carbon products of CN- and SCN- decomposition. The terminal sulfur products of SCN- decomposition by P. stutzeri strain 18 and P. putida strain 21 were thiosulfate and tetrathionate, respectively. The strains utilized the toxic compounds in the anabolism only, as sources of nitrogen (CN- and SCN-) and sulfur (SCN-). The pathway of thiocyanate decomposition by the association of bacteria of the genus Pseudomonas is proposed based on the results obtained.

  17. Pseudomonas putida and Pseudomonas fluorescens Species Group Recovery from Human Homes Varies Seasonally and by Environment.

    Directory of Open Access Journals (Sweden)

    Susanna K Remold

    Full Text Available By shedding light on variation in time as well as in space, long-term biogeographic studies can help us define organisms' distribution patterns and understand their underlying drivers. Here we examine distributions of Pseudomonas in and around 15 human homes, focusing on the P. putida and P. fluorescens species groups. We describe recovery from 10,941 samples collected during up to 8 visits per home, occurring on average 2.6 times per year. We collected a mean of 141 samples per visit, from sites in most rooms of the house, from the surrounding yards, and from human and pet occupants. We recovered Pseudomonas in 9.7% of samples, with the majority of isolates being from the P. putida and P. fluorescens species groups (approximately 62% and 23% of Pseudomonas samples recovered respectively. Although representatives of both groups were recovered from every season, every house, and every type of environment sampled, recovery was highly variable across houses and samplings. Whereas recovery of P. putida group was higher in summer and fall than in winter and spring, P. fluorescens group isolates were most often recovered in spring. P. putida group recovery from soils was substantially higher than its recovery from all other environment types, while higher P. fluorescens group recovery from soils than from other sites was much less pronounced. Both species groups were recovered from skin and upper respiratory tract samples from healthy humans and pets, although this occurred infrequently. This study indicates that even species that are able to survive under a broad range of conditions can be rare and variable in their distributions in space and in time. For such groups, determining patterns and causes of stochastic and seasonal variability may be more important for understanding the processes driving their biogeography than the identity of the types of environments in which they can be found.

  18. [Toxocara sp. eggs and Ancylostoma sp. larva in public parks, Brazil].

    Science.gov (United States)

    Guimarães, Antônio Marcos; Alves, Endrigo Gabellini Leonel; de Rezende, Glycia Ferreira; Rodrigues, Marcelo Costa

    2005-04-01

    Visceral and cutaneous larva migrans are parasitic zoonoses caused by the infection of larval nematodes Toxocara sp. and Ancylostoma sp. respectively. The objective of this study was to investigate the contamination by Toxocara sp. eggs and Ancylostoma sp. eggs and larva of soil samples collected from public parks and children's playground areas in state of Minas Gerais, Brazil, using both Baermann's method and centrifugal flotation technique. Toxocara sp. and Ancylostoma sp. eggs were observed in soil samples collected from public squares in 17.4% (4/23) and 69.6 (16/23) respectively. In schools and child day care settings the contamination by Ancylostoma sp. larva in sand samples was 11.1% (2/18). Public parks are settings of more potential risk of Toxocara sp. eggs and Ancylostoma sp. infection. Stool parasitology testing of 174 stool samples showed 58% and 23% of Ancylostoma sp and Toxocara sp eggs infection respectively.

  19. Lactobacillus apinorum sp. nov., Lactobacillus mellifer sp. nov., Lactobacillus mellis sp. nov., Lactobacillus melliventris sp. nov., Lactobacillus kimbladii sp. nov., Lactobacillus helsingborgensis sp. nov. and Lactobacillus kullabergensis sp. nov., isolated from the honey stomach of the honeybee Apis mellifera.

    Science.gov (United States)

    Olofsson, Tobias C; Alsterfjord, Magnus; Nilson, Bo; Butler, Eile; Vásquez, Alejandra

    2014-09-01

    We previously discovered a symbiotic lactic acid bacterial (LAB) microbiota in the honey stomach of the honeybee Apis mellifera. The microbiota was composed of several phylotypes of Bifidobacterium and Lactobacillus. 16S rRNA gene sequence analyses and phenotypic and genetic characteristics revealed that the phylotypes isolated represent seven novel species. One grouped with Lactobacillus kunkeei and the others belong to the Lactobacillus buchneri and Lactobacillus delbrueckii subgroups of Lactobacillus. We propose the names Lactobacillus apinorum sp. nov., Lactobacillus mellifer sp. nov., Lactobacillus mellis sp. nov., Lactobacillus melliventris sp. nov., Lactobacillus kimbladii sp. nov., Lactobacillus helsingborgensis sp. nov. and Lactobacillus kullabergensis sp. nov. for these novel species, with the respective type strains being Fhon13N(T) ( = DSM 26257(T) = CCUG 63287(T)), Bin4N(T) ( = DSM 26254(T) = CCUG 63291(T)), Hon2N(T) ( = DSM 26255(T) = CCUG 63289(T)), Hma8N(T) ( = DSM 26256(T) = CCUG 63629(T)), Hma2N(T) ( = DSM 26263(T) = CCUG 63633(T)), Bma5N(T) ( = DSM 26265(T) = CCUG 63301(T)) and Biut2N(T) ( = DSM 26262(T) = CCUG 63631(T)).

  20. Spoilage potential of Pseudomonas species isolated from goat milk.

    Science.gov (United States)

    Scatamburlo, T M; Yamazi, A K; Cavicchioli, V Q; Pieri, F A; Nero, L A

    2015-02-01

    Pseudomonas spp. are usually associated with spoilage microflora of dairy products due to their proteolytic potential. This is of particular concern for protein-based products, such as goat milk cheeses and fermented milks. Therefore, the goal of the present study was to characterize the proteolytic activity of Pseudomonas spp. isolated from goat milk. Goat milk samples (n=61) were obtained directly from bulk tanks on dairy goat farms (n=12), and subjected to a modified International Organization for Standardization (ISO) protocol to determine the number and proteolytic activity of Pseudomonas spp. Isolates (n=82) were obtained, identified by PCR, and subjected to pulsed-field gel electrophoresis with XbaI macro-restriction. Then, the isolates were subjected to PCR to detect the alkaline protease gene (apr), and phenotypic tests were performed to check proteolytic activity at 7°C, 25°C, and 35°C. Mean Pseudomonas spp. counts ranged from 2.9 to 4.8 log cfu/mL, and proteolytic Pseudomonas spp. counts ranged from 1.9 to 4.6 log cfu/mL. All isolates were confirmed to be Pseudomonas spp., and 41 were identified as Pseudomonas fluorescens, which clustered into 5 groups sharing approximately 82% similarity. Thirty-six isolates (46.9%) were positive for the apr gene; and 57 (69.5%) isolates presented proteolytic activity at 7°C, 82 (100%) at 25°C, and 64 (78%) at 35°C. The isolates were distributed ubiquitously in the goat farms, and no relationship among isolates was observed when the goat farms, presence of apr, pulsotypes, and proteolytic activity were taken into account. We demonstrated proteolytic activity of Pseudomonas spp. present in goat milk by phenotypic and genotypic tests and indicated their spoilage potential at distinct temperatures. Based on these findings and the ubiquity of Pseudomonas spp. in goat farm environments, proper monitoring and control of Pseudomonas spp. during production are critical.

  1. Functional redundancy in phenol and toluene degradation in Pseudomonas stutzeri strains isolated from the Baltic Sea.

    Science.gov (United States)

    Heinaru, Eeva; Naanuri, Eve; Grünbach, Maarja; Jõesaar, Merike; Heinaru, Ain

    2016-09-01

    In the present study we describe functional redundancy of bacterial multicomponent monooxygenases (toluene monooxygenase (TMO) and toluene/xylene monooxygenase (XylAM) of TOL pathway) and cooperative genetic regulation at the expression of the respective catabolic operons by touR and xylR encoded regulatory circuits in five phenol- and toluene-degrading Pseudomonas stutzeri strains. In these strains both toluene degradation pathways (TMO and Xyl) are active and induced by toluene and phenol. The whole genome sequence of the representative strain 2A20 revealed the presence of complete TMO- and Xyl-upper pathway operons together with two sets of lower catechol meta pathway operons, as well as phenol-degrading operon in a single 292,430bp contig. The much lower GC content and analysis of the predicted ORFs refer to the plasmid origin of the approximately 130kb region of this contig, containing the xyl, phe and tou genes. The deduced amino acid sequences of the TMO, XylA and the large subunit of phenol monooxygenase (LmPH) show 98-100% identity with the respective gene products of the strain Pseudomonas sp. OX1. In both strains 2A20 and OX1 the meta-cleavage pathways for catechol degradation are coded by two redundant operons (phe and xyl). We show that in the strain 2A20 TouR and XylR are activated by different effector molecules, phenol and toluene, respectively, and they both control transcription of the xyl upper, tou (TMO) and phe catabolic operons. Although the growth parameters of redundant strains did not show advantage at toluene biodegradation, the functional redundancy could provide better flexibility to the bacteria in environmental conditions. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. Pseudomonas syringae pv. phaseolicola isolated from weeds in bean crop fields.

    Science.gov (United States)

    Fernández-Sanz, A M; Rodicio, M R; González, A J

    2016-04-01

    Pseudomonas syringae pv. phaseolicola, the causative agent of halo blight in common bean (Phaseolus vulgaris L.), was isolated from weeds associated with bean crops in Spain. The bacterium was recovered from Fumaria sp, Mercurialis annua, Solanum nigrum and Sonchus oleraceus. Ps. s. pv. phaseolicola had previously been isolated from leguminous plants and S. nigrum, but to our knowledge, this is the first time it was recovered from the other three species. The isolates were phenotypically and genetically characterized, and they were compared with isolates recovered from common beans. Five different genotypic profiles were detected by PmeI-PFGE, two of them being of new description. Weed isolates were as pathogenic on bean plants as bean isolates, but they were not pathogenic on S. nigrum. Regarding the survival of the pathogen in weeds, Ps. s. pv. phaseolicola was isolated from So. oleraceus 11 weeks after the end of the bean crop. These results strongly support the idea of weeds as a potential source of inoculum for halo blight in bean. It has traditionally been considered that the main source of inoculum of Pseudomonas syringae pv. phaseolicola causing halo blight disease in Phaseolus vulgaris are the bean seeds, and that the host range of the bacterium is almost restricted to leguminous plants. In this study, the bacterium was recovered from four nonleguminous weed species collected in bean fields, and its permanence in weeds for at least 11 weeks after the harvesting of the beans was demonstrated. We have also proved that the strains isolated from weeds were pathogenic on bean plants. Accordingly, the host range of Ps. s. pv. phaseolicola could be broader than previously thought and weeds appear to be acting as a reservoir of the pathogen until the next crop. © 2016 The Society for Applied Microbiology.

  3. Strategy of Pseudomonas pseudoalcaligenes C70 for effective degradation of phenol and salicylate

    Science.gov (United States)

    Heinaru, Eeva; Naanuri, Eve; Mehike, Maris; Leito, Ivo; Heinaru, Ain

    2017-01-01

    Phenol- and naphthalene-degrading indigenous Pseudomonas pseudoalcaligenes strain C70 has great potential for the bioremediation of polluted areas. It harbours two chromosomally located catechol meta pathways, one of which is structurally and phylogenetically very similar to the Pseudomonas sp. CF600 dmp operon and the other to the P. stutzeri AN10 nah lower operon. The key enzymes of the catechol meta pathway, catechol 2,3-dioxygenase (C23O) from strain C70, PheB and NahH, have an amino acid identity of 85%. The metabolic and regulatory phenotypes of the wild-type and the mutant strain C70ΔpheB lacking pheB were evaluated. qRT-PCR data showed that in C70, the expression of pheB- and nahH-encoded C23O was induced by phenol and salicylate, respectively. We demonstrate that strain C70 is more effective in the degradation of phenol and salicylate, especially at higher substrate concentrations, when these compounds are present as a mixture; i.e., when both pathways are expressed. Moreover, NahH is able to substitute for the deleted PheB in phenol degradation when salicylate is also present in the growth medium. The appearance of a yellow intermediate 2-hydroxymuconic semialdehyde was followed by the accumulation of catechol in salicylate-containing growth medium, and lower expression levels and specific activities of the C23O of the sal operon were detected. However, the excretion of the toxic intermediate catechol to the growth medium was avoided when the growth medium was supplemented with phenol, seemingly due to the contribution of the second meta pathway encoded by the phe genes. PMID:28257519

  4. Pantoea vagans sp. nov., Pantoea eucalypti sp. nov., Pantoea deleyi sp. nov. and Pantoea anthophila sp. nov.

    Science.gov (United States)

    Brady, Carrie L; Venter, Stephanus N; Cleenwerck, Ilse; Engelbeen, Katrien; Vancanneyt, Marc; Swings, Jean; Coutinho, Teresa A

    2009-09-01

    Bacteria isolated from eucalyptus leaves and shoots showing symptoms of blight and die-back collected in Uganda, Uruguay and Argentina and from maize displaying brown stalk rot symptoms in South Africa were tentatively placed in the genus Pantoea on the basis of phenotypic and biochemical tests. These isolates, together with two strains (LMG 2558 and LMG 2560) previously assigned to Pantoea agglomerans based on protein electrophoregrams but later excluded from this species, were further investigated using molecular techniques. 16S rRNA gene sequencing and multilocus sequence analyses (MLSA) revealed that the strains were phylogenetically closely related to Pantoea agglomerans, Pantoea stewartii and Pantoea ananatis. MLSA and amplified fragment length polymorphism analysis placed the strains into four separate clusters, not containing any of the type strains of species of the genus Pantoea. DNA-DNA hybridization confirmed the classification of the isolates into four novel species, for which the names Pantoea vagans sp. nov. (type strain R-21566T=LMG 24199T=BCC 105T=BD 765T), Pantoea eucalypti sp. nov. (type strain R-25678T=LMG 24197T=BCC 076T=BD 769T), Pantoea deleyi sp. nov. (type strain R-31523T=LMG 24200T=BCC 109T=BD 767T) and Pantoea anthophila sp. nov. (type strain LMG 2558T=BD 871T=NCPPB 1682T) are proposed.

  5. Development of a Pseudomonas aeruginosa Agmatine Biosensor

    Directory of Open Access Journals (Sweden)

    Adam Gilbertsen

    2014-10-01

    Full Text Available Agmatine, decarboxylated arginine, is an important intermediary in polyamine production for many prokaryotes, but serves higher functions in eukaryotes such as nitric oxide inhibition and roles in neurotransmission. Pseudomonas aeruginosa relies on the arginine decarboxylase and agmatine deiminase pathways to convert arginine into putrescine. One of the two known agmatine deiminase operons, aguBA, contains an agmatine sensitive TetR promoter controlled by AguR. We have discovered that this promoter element can produce a titratable induction of its gene products in response to agmatine, and utilized this discovery to make a luminescent agmatine biosensor in P. aeruginosa. The genome of the P. aeruginosa lab strain UCBPP-PA14 was altered to remove both its ability to synthesize or destroy agmatine, and insertion of the luminescent reporter construct allows it to produce light in proportion to the amount of exogenous agmatine applied from ~100 nM to 1mM. Furthermore it does not respond to related compounds including arginine or putrescine. To demonstrate potential applications the biosensor was used to detect agmatine in spent supernatants, to monitor the development of arginine decarboxylase over time, and to detect agmatine in the spinal cords of live mice.

  6. Antivirulence activity of azithromycin in Pseudomonas aeruginosa

    Directory of Open Access Journals (Sweden)

    Francesco eImperi

    2014-04-01

    Full Text Available Antibiotics represent our bulwark to combat bacterial infections, but the spread of antibiotic resistance compromises their clinical efficacy. Alternatives to conventional antibiotics are urgently needed in order to complement the existing antibacterial arsenal. The macrolide antibiotic azithromycin (AZM provides a paradigmatic example of an unconventional antibacterial drug. Besides its growth-inhibiting activity, AZM displays potent anti-inflammatory properties, as well as antivirulence activity on some intrinsically resistant bacteria, such as Pseudomonas aeruginosa. In this bacterium, the antivirulence activity of AZM mainly relies on its ability to interact with the ribosome, resulting in direct and/or indirect repression of specific subsets of genes involved in virulence, quorum sensing, biofilm formation and intrinsic antibiotic resistance. Both clinical experience and clinical trials have shown the efficacy of AZM in the treatment of chronic pulmonary infections caused by P. aeruginosa. The aim of this review is to combine results from laboratory studies with evidence from clinical trials in order to unify the information on the in vivo mode of action of AZM in P. aeruginosa infection.

  7. Spaceflight promotes biofilm formation by Pseudomonas aeruginosa.

    Directory of Open Access Journals (Sweden)

    Wooseong Kim

    Full Text Available Understanding the effects of spaceflight on microbial communities is crucial for the success of long-term, manned space missions. Surface-associated bacterial communities, known as biofilms, were abundant on the Mir space station and continue to be a challenge on the International Space Station. The health and safety hazards linked to the development of biofilms are of particular concern due to the suppression of immune function observed during spaceflight. While planktonic cultures of microbes have indicated that spaceflight can lead to increases in growth and virulence, the effects of spaceflight on biofilm development and physiology remain unclear. To address this issue, Pseudomonas aeruginosa was cultured during two Space Shuttle Atlantis missions: STS-132 and STS-135, and the biofilms formed during spaceflight were characterized. Spaceflight was observed to increase the number of viable cells, biofilm biomass, and thickness relative to normal gravity controls. Moreover, the biofilms formed during spaceflight exhibited a column-and-canopy structure that has not been observed on Earth. The increase in the amount of biofilms and the formation of the novel architecture during spaceflight were observed to be independent of carbon source and phosphate concentrations in the media. However, flagella-driven motility was shown to be essential for the formation of this biofilm architecture during spaceflight. These findings represent the first evidence that spaceflight affects community-level behaviors of bacteria and highlight the importance of understanding how both harmful and beneficial human-microbe interactions may be altered during spaceflight.

  8. Bioadsorption characteristics of Pseudomonas aeruginosa PAOI

    Directory of Open Access Journals (Sweden)

    Kőnig-Péter Anikó

    2014-01-01

    Full Text Available Biosorption of Cd(II and Pb(II ions from aqueous solution using lyophilized Pseudomonas aeruginosa (PAOI cells were observed under various experimental conditions. The effect of pH, initial metal concentration, equilibration time and temperature on bioadsorption was investigated. The optimum pH value for Pb(II adsorption was found to be 5.0, and for Cd(II 5.0 − 6.0. The Pb(II and Cd(II bioadsorption equilibrium were analyzed by using Freundlich and Langmuir model using nonlinear least-squares estimation. The experimental maximum uptake capacity of Pb(II and Cd(II was estimated to be 164 mg g-1 and 113 mg g-1, respectively. For biosorption kinetic study the pseudo second-order kinetic model was applied at various temperatures. The temperature had no significant effect on Pb(II bioadsorption. In case of Cd(II bioadsorption the adsorbed amount decreased with increasing temperature.

  9. Pseudomonas biofilms: possibilities of their control.

    Science.gov (United States)

    Masák, Jan; Čejková, Alena; Schreiberová, Olga; Rezanka, Tomáš

    2014-07-01

    Genus Pseudomonas includes a large number of species that can be encountered in biotechnological processes as well as in the role of serious human or plant pathogens. Pseudomonads easily form biofilms on various types of surfaces. The biofilm phenotype is characterized by an increased resistance to environmental influences including resistance to antibiotics and other disinfectants, causing a number of problems in health care, food industry, and other areas. Considerable attention is therefore paid to the possibilities of eradication/destruction of pseudomonads biofilms both in terms of understanding the mechanisms of biofilm formation and at the level of finding suitable antibiofilm tools applicable in practice. The first part of this review is devoted to an overview of the regulatory mechanisms that are directly or indirectly involved in the formation of biofilm. The most effective approaches to suppressing the formation of biofilm that do not cause the development of resistance are based on the application of substances that interfere with the regulatory molecules or block the appropriate regulatory mechanisms involved in biofilm development by the cells. Pseudomonads biofilm formation is, similar to other microorganisms, a sophisticated process with many regulatory elements. The suppression of this process therefore also requires multiple antibiofilm tools.

  10. Pseudomonas aeruginosa ventilator-associated pneumonia management

    Directory of Open Access Journals (Sweden)

    Ramírez-Estrada S

    2016-01-01

    Full Text Available Sergio Ramírez-Estrada,1 Bárbara Borgatta,1,2 Jordi Rello3,4 1Critical Care Department, Vall d'Hebron University Hospital, 2CRIPS, Vall d'Hebron Institute of Research (VHIR, 3Department of Medicine, Universitat Autònoma de Barcelona (UAB, Barcelona, 4Centro de Investigación Biomédica en Red Enfermedad Respiratoria – CIBERES, Madrid, Spain Abstract: Ventilator-associated pneumonia is the most common infection in intensive care unit patients associated with high morbidity rates and elevated economic costs; Pseudomonas aeruginosa is one of the most frequent bacteria linked with this entity, with a high attributable mortality despite adequate treatment that is increased in the presence of multiresistant strains, a situation that is becoming more common in intensive care units. In this manuscript, we review the current management of ventilator-associated pneumonia due to P. aeruginosa, the most recent antipseudomonal agents, and new adjunctive therapies that are shifting the way we treat these infections. We support early initiation of broad-spectrum antipseudomonal antibiotics in present, followed by culture-guided monotherapy de-escalation when susceptibilities are available. Future management should be directed at blocking virulence; the role of alternative strategies such as new antibiotics, nebulized treatments, and vaccines is promising. Keywords: multidrug-resistant, ICU, new-antibiotics, adjunctive-therapies, care-bundles

  11. Definition of Plant-Pathogenic Pseudomonas Genomospecies of the Pseudomonas syringae Complex Through Multiple Comparative Approaches.

    Science.gov (United States)

    Marcelletti, Simone; Scortichini, Marco

    2014-12-01

    A total of 34 phytopathogenic strain genomes belonging to the Pseudomonas syringae species complex and related species, including many pathotype strains, were assessed using average nucleotide identity (ANI) analysis. Their taxonomic relationships were consistently confirmed by the tetranucleotide frequency correlation coefficient (TETRA) values, multilocus sequence typing analysis (MLSA) performed with seven housekeeping genes, using both maximum likelihood and Bayesian methods, and split consensus network analyses. The ANI, MLSA, and split consensus analyses provided consistent and identical results. We confirmed the occurrence of the well-demarcated genomospecies inferred sensu Gardan et al. using DNA-DNA hybridization and ribotyping analyses. However, some P. syringae strains of the pathovars morsprunorum and lachrymans were placed in different genomospecies in our analyses. Genomospecies 1, 2, 4, 6, and 9 resulted well demarcated, whereas strains of genomospecies 3 and 8 had ANI values between 95 and 96% in some cases, confirming that this threshold reveals very closely related species that might represent cases of splitting entities or the convergence of different species to the same ecological niche. This study confirms the robustness of the combination of genomic and phylogenetic approaches in revealing taxonomic relationships among closely related bacterial strains and provides the basis for a further reliable demarcation of the phytopathogenic Pseudomonas species. Within each species, the pathovars might represent distinct ecological units. The possibility of performing extensive and standardized host range and phenotypic tests with many strains of different pathovars can assist phytobacteriologists for better determining the boundaries of these ecological units.

  12. Biodegradation of stored jet fuel by a Nocardia sp. isolated from contaminated soil

    Directory of Open Access Journals (Sweden)

    Edelvio de Barros Gomes

    2009-10-01

    Full Text Available The aim of this study was to investigate the potential of degradation of an autochthonous bacterial strain, isolated from petroleum derivatives contaminated soil samples against jet fuel hydrocarbons. The autochthonous bacterial strain was characterized as Nocardia sp. Evaluation of their degrading abilities was carried out by presumptive assays as redox indicator test and by observations of surface tension decreases in aqueous medium. Degradation of jet fuel hydrocarbons was evaluated by chromatographic methods. Experiments were performed in flasks at two biostimulation rates. A bacterial strain of Pseudomonas aeruginosa UFPEDA 39 was utilized as a reference microorganism. The bacterial strain, identified as Nocardia sp, demonstrate high ability to degrade jet fuel compounds as well as to produce surface active compounds when compared to the reference microrganism.O presente estudo objetivou a investigação da capacidade degradadora de uma linhagem bacteriana autóctone (isolada de amostras de solo contaminadas com derivados de petróleo contra hidrocarbonetos de querosene de aviação. A linhagem foi caracterizada como Nocardia sp. A avaliação do seu potencial degradador deu-se realizada mediante testes com indicador redox e observações na redução da tensão superficial na fase aquosa. A degradação do querosene foi avaliada por métodos cromatográficos. Os experimentos foram realizados utilizando-se duas taxas de bioestímulo. Uma linhagem bacteriana Pseudomonas aeruginosa UFPEDA 39 foi utilizada como referência. A linhagem autóctone demonstrou alta eficiência na degradação de hidrocarbonetos do querosene bem como para produzir compostos ativos de superfície quando comparada com a linhagem de referência.

  13. Marine Sponge-Derived Streptomyces sp. SBT343 Extract Inhibits Staphylococcal Biofilm Formation

    Science.gov (United States)

    Balasubramanian, Srikkanth; Othman, Eman M.; Kampik, Daniel; Stopper, Helga; Hentschel, Ute; Ziebuhr, Wilma; Oelschlaeger, Tobias A.; Abdelmohsen, Usama R.

    2017-01-01

    Staphylococcus epidermidis and Staphylococcus aureus are opportunistic pathogens that cause nosocomial and chronic biofilm-associated infections. Indwelling medical devices and contact lenses are ideal ecological niches for formation of staphylococcal biofilms. Bacteria within biofilms are known to display reduced susceptibilities to antimicrobials and are protected from the host immune system. High rates of acquired antibiotic resistances in staphylococci and other biofilm-forming bacteria further hamper treatment options and highlight the need for new anti-biofilm strategies. Here, we aimed to evaluate the potential of marine sponge-derived actinomycetes in inhibiting biofilm formation of several strains of S. epidermidis, S. aureus, and Pseudomonas aeruginosa. Results from in vitro biofilm-formation assays, as well as scanning electron and confocal microscopy, revealed that an organic extract derived from the marine sponge-associated bacterium Streptomyces sp. SBT343 significantly inhibited staphylococcal biofilm formation on polystyrene, glass and contact lens surfaces, without affecting bacterial growth. The extract also displayed similar antagonistic effects towards the biofilm formation of other S. epidermidis and S. aureus strains tested but had no inhibitory effects towards Pseudomonas biofilms. Interestingly the extract, at lower effective concentrations, did not exhibit cytotoxic effects on mouse fibroblast, macrophage and human corneal epithelial cell lines. Chemical analysis by High Resolution Fourier Transform Mass Spectrometry (HRMS) of the Streptomyces sp. SBT343 extract proportion revealed its chemical richness and complexity. Preliminary physico-chemical characterization of the extract highlighted the heat-stable and non-proteinaceous nature of the active component(s). The combined data suggest that the Streptomyces sp. SBT343 extract selectively inhibits staphylococcal biofilm formation without interfering with bacterial cell viability. Due to

  14. Bioaugmentation of Mesorhizobium cicer, Pseudomonas spp. and Piriformospora indica for Sustainable Chickpea Production.

    Science.gov (United States)

    Mansotra, Pallavi; Sharma, Poonam; Sharma, Sunita

    2015-07-01

    Chickpea establishes symbiotic association with Mesorhizobium to fulfill its nitrogen (N) requirement. Integrating chickpea rhizosphere with potential native mesorhizobia and other plant growth promoting microorganisms can contribute multiple benefits to plants. The present investigation was undertaken to study interactions among Piriformospora indica (PI) with potential plant growth promoting rhizobacteria (PGPR) viz. Pseudomonas argentinensis (LPGPR1), Pseudomonas sp. (LPGPR2) along with national check Pseudomons sp. (LK884) and Mesorhizobium cicer (LGR33, MR) to examine the synergistic effect of consortium for improving growth, symbiotic efficiency, nutrient acquisition and yield in two chickpea (Cicer arietinum L.) varieties viz. desi PBG1 and kabuli BG1053. In-vitro, seed germination with consortium MR + PI + LPGPR1 was the best compatible treatment followed by MR + PI + LK884 and MR + PI + LPGPR2. Significant improvement in the growth, symbiotic parameters and grain yield was observed with MR + PI + LPGPR1 and MR + PI + LK884 treatments. Significantly high chlorophyll and leghaemoglobin content was recorded with MR + PI + LPGPR1 (1.57 and 1.64 mg g(-1) fresh weight of leaves and 5.19 and 4.39 mg/g(-1) fresh weight of nodules) in desi PBG1 and kabuli BG1053 chickpea varieties, respectively. At 90 DAS, MR + PI + LPGPR1 treatment significantly improved nodule dry weight (ranged between 84.0 and 141.7 mg plant(-1)) as compared to MR alone treatment (ranged between 62.3 and 123.3 mg plant(-1)). Data revealed significant increase in total nitrogen (N) and phosphorus (P) content of shoot with MR + PI + LPGPR1 by 1.2 and 1.5 fold, respectively over MR alone treatment. On the basis of overall mean, MR + PI + LPGPR1 significantly improved the yield by 8.2 % over Mesorhizobium alone application. It seems from foregoing study that tripartite combination of different micro-organisms can be

  15. No apparent costs for facultative antibiotic production by the soil bacterium Pseudomonas fluorescens Pf0-1.

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    Paolina Garbeva

    Full Text Available BACKGROUND: Many soil-inhabiting bacteria are known to produce secondary metabolites that can suppress microorganisms competing for the same resources. The production of antimicrobial compounds is expected to incur fitness costs for the producing bacteria. Such costs form the basis for models on the co-existence of antibiotic-producing and non-antibiotic producing strains. However, so far studies quantifying the costs of antibiotic production by bacteria are scarce. The current study reports on possible costs, for antibiotic production by Pseudomonas fluorescens Pf0-1, a soil bacterium that is induced to produce a broad-spectrum antibiotic when it is confronted with non-related bacterial competitors or supernatants of their cultures. METHODOLOGY AND PRINCIPAL FINDINGS: We measured the possible cost of antibiotic production for Pseudomonas fluorescens Pf0-1 by monitoring changes in growth rate with and without induction of antibiotic production by supernatant of a bacterial competitor, namely Pedobacter sp.. Experiments were performed in liquid as well as on semi-solid media under nutrient-limited conditions that are expected to most clearly reveal fitness costs. Our results did not reveal any significant costs for production of antibiotics by Pseudomonas fluorescens Pf0-1. Comparison of growth rates of the antibiotic-producing wild-type cells with those of non-antibiotic producing mutants did not reveal costs of antibiotic production either. SIGNIFICANCE: Based on our findings we propose that the facultative production of antibiotics might not be selected to mitigate metabolic costs, but instead might be advantageous because it limits the risk of competitors evolving resistance, or even the risk of competitors feeding on the compounds produced.

  16. Ethylene production with engineered Synechocystis sp PCC 6803 strains.

    Science.gov (United States)

    Veetil, Vinod Puthan; Angermayr, S Andreas; Hellingwerf, Klaas J

    2017-02-23

    Metabolic engineering and synthetic biology of cyanobacteria offer a promising sustainable alternative approach for fossil-based ethylene production, by using sunlight via oxygenic photosynthesis, to convert carbon dioxide directly into ethylene. Towards this, both well-studied cyanobacteria, i.e., Synechocystis sp PCC 6803 and Synechococcus elongatus PCC 7942, have been engineered to produce ethylene by introducing the ethylene-forming enzyme (Efe) from Pseudomonas syringae pv. phaseolicola PK2 (the Kudzu strain), which catalyzes the conversion of the ubiquitous tricarboxylic acid cycle intermediate 2-oxoglutarate into ethylene. This study focuses on Synechocystis sp PCC 6803 and shows stable ethylene production through the integration of a codon-optimized version of the efe gene under control of the Ptrc promoter and the core Shine-Dalgarno sequence (5'-AGGAGG-3') as the ribosome-binding site (RBS), at the slr0168 neutral site. We have increased ethylene production twofold by RBS screening and further investigated improving ethylene production from a single gene copy of efe, using multiple tandem promoters and by putting our best construct on an RSF1010-based broad-host-self-replicating plasmid, which has a higher copy number than the genome. Moreover, to raise the intracellular amounts of the key Efe substrate, 2-oxoglutarate, from which ethylene is formed, we constructed a glycogen-synthesis knockout mutant (ΔglgC) and introduced the ethylene biosynthetic pathway in it. Under nitrogen limiting conditions, the glycogen knockout strain has increased intracellular 2-oxoglutarate levels; however, surprisingly, ethylene production was lower in this strain than in the wild-type background. Making use of different RBS sequences, production of ethylene ranging over a 20-fold difference has been achieved. However, a further increase of production through multiple tandem promoters and a broad-host plasmid was not achieved speculating that the transcription strength and

  17. An Sp1/Sp3 binding polymorphism confers methylation protection.

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    Yanis A Boumber

    2008-08-01

    Full Text Available Hundreds of genes show aberrant DNA hypermethylation in cancer, yet little is known about the causes of this hypermethylation. We identified RIL as a frequent methylation target in cancer. In search for factors that influence RIL hypermethylation, we found a 12-bp polymorphic sequence around its transcription start site that creates a long allele. Pyrosequencing of homozygous tumors revealed a 2.1-fold higher methylation for the short alleles (P<0.001. Bisulfite sequencing of cancers heterozygous for RIL showed that the short alleles are 3.1-fold more methylated than the long (P<0.001. The comparison of expression levels between unmethylated long and short EBV-transformed cell lines showed no difference in expression in vivo. Electrophorectic mobility shift assay showed that the inserted region of the long allele binds Sp1 and Sp3 transcription factors, a binding that is absent in the short allele. Transient transfection of RIL allele-specific transgenes showed no effects of the additional Sp1 site on transcription early on. However, stable transfection of methylation-seeded constructs showed gradually decreasing transcription levels from the short allele with eventual spreading of de novo methylation. In contrast, the long allele showed stable levels of expression over time as measured by luciferase and approximately 2-3-fold lower levels of methylation by bisulfite sequencing (P<0.001, suggesting that the polymorphic Sp1 site protects against time-dependent silencing. Our finding demonstrates that, in some genes, hypermethylation in cancer is dictated by protein-DNA interactions at the promoters and provides a novel mechanism by which genetic polymorphisms can influence an epigenetic state.

  18. Effect of NaCl on Pseudomonas biofilm viscosity by continuous, non-intrusive microfluidic-based approach

    CERN Document Server

    Paquet-Mercier, Francois; Bellavance, Julien; Taghavi, Seyed Mohammad; Greener, Jesse

    2016-01-01

    A method combining video imaging in parallel microchannels with a semi-empirical mathematical model provides non-intrusive, high-throughput measurements of time-varying biofilm viscosity. The approach is demonstrated for early growth Pseudomonas sp. biofilms exposed to constant flow streams of nutrient solutions with different ionic strengths. The ability to measure viscosities at early growth stages, without inducing a shear-thickening response, enabled measurements that are among the lowest reported to date. In addition, good time resolution enabled the detection of a rapid thickening phase, which occurred at different times after the exponential growth phase finished, depending on the ionic strength. The technique opens the way for a combinatorial approach to beter understand the complex dynamical response of biofilm mechanical properties under well-controlled physical, chemical and biological growth conditions and time-limited perturbations.

  19. Crystal structure of dihydropyrimidinase from Pseudomonas aeruginosa PAO1: Insights into the molecular basis of formation of a dimer.

    Science.gov (United States)

    Tzeng, Ching-Ting; Huang, Yen-Hua; Huang, Cheng-Yang

    2016-09-23

    Dihydropyrimidinase, a tetrameric metalloenzyme, is a member of the cyclic amidohydrolase family, which also includes allantoinase, dihydroorotase, hydantoinase, and imidase. In this paper, we report the crystal structure of dihydropyrimidinase from Pseudomonas aeruginosa PAO1 at 2.1 Å resolution. The structure of P. aeruginosa dihydropyrimidinase reveals a classic (β/α)8-barrel structure core embedding the catalytic dimetal center and a β-sandwich domain, which is commonly found in the architecture of dihydropyrimidinases. In contrast to all dihydropyrimidinases, P. aeruginosa dihydropyrimidinase forms a dimer, rather than a tetramer, both in the crystalline state and in the solution. Basing on sequence analysis and structural comparison of the C-terminal region and the dimer-dimer interface between P. aeruginosa dihydropyrimidinase and Thermus sp. dihydropyrimidinase, we propose a working model to explain why this enzyme cannot be a tetramer.

  20. Susceptibility trends of pseudomonas species from corneal ulcers.

    Science.gov (United States)

    Smitha, S; Lalitha, P; Prajna, V N; Srinivasan, M

    2005-07-01

    To assess the changing trends in the antibiotic susceptibility of Pseudomonas spp . isolated from bacterial keratitis over a nine year period with special emphasis on fluoroquinolone susceptibilities. All corneal scraping cultures positive for Pseudomonas spp. (n=585) isolated from patients with bacterial keratitis at the Aravind Eye Hospital, Madurai from 1995-2003 were evaluated. Cultures were performed in liquid and solid media and susceptibility testing was done against amikacin, gentamicin, tobramycin, ciprofloxacin and ofloxacin by Kirby-Bauer disc diffusion method. The susceptibility of Pseudomonas spp. was over 90% from 1995-1998 to ciprofloxacin which decreased to 83% from 1999-2003. The total number of isolates resistant to ciprofloxacin was 51 (9.4%). No statistically significant increase in the number of isolates resistant to ciprofloxacin was noted. Ofloxacin showed 54% susceptibility from 1995-1998 but increased to 64% from 1999-2003. Analysis of in vitro activity of amikacin reveals that there was 43% sensitivity from 1995-1998 but later it increased to 76% from 1999-2003. In case of gentamicin, the sensitivity decreased marginally from 80% to 70% through the years. Tobramycin showed 45% sensitivity from 1995-1998 but increased to 75% from 1999-2003. The fluoroquinolones remain a good choice in the treatment of ocular infections, with high susceptibility of Pseudomonas spp. Among the aminoglycosides, gentamicin was found to be highly effective against Pseudomonas corneal ulcers when compared to amikacin and tobramycin. The results show a need for continuous monitoring of bacterial resistance trends.

  1. Genotypic diversity and rhizosphere competence of antibiotic-producing Pseudomonas species

    NARCIS (Netherlands)

    Bergsma-Vlami, M.

    2008-01-01

    The phenolic antibiotic 2,4-diacetylphloroglucinol (DAPG) has been implicated in biological control of multiple plant pathogens by fluorescent Pseudomonas species. DAPG-producing Pseudomonas strains are effective biocontrol agents, however, their ecological performance is often highly variable resul

  2. Aflatoxin B₁ degradation by a Pseudomonas strain.

    Science.gov (United States)

    Sangare, Lancine; Zhao, Yueju; Folly, Yawa Minnie Elodie; Chang, Jinghua; Li, Jinhan; Selvaraj, Jonathan Nimal; Xing, Fuguo; Zhou, Lu; Wang, Yan; Liu, Yang

    2014-10-23

    Aflatoxin B1 (AFB1), one of the most potent naturally occurring mutagens and carcinogens, causes significant threats to the food industry and animal production. In this study, 25 bacteria isolates were collected from grain kernels and soils displaying AFB1 reduction activity. Based on its degradation effectiveness, isolate N17-1 was selected for further characterization and identified as Pseudomonas aeruginosa. P. aeruginosa N17-1 could degrade AFB₁, AFB₂ and AFM₁ by 82.8%, 46.8% and 31.9% after incubation in Nutrient Broth (NB) medium at 37 °C for 72 h, respectively. The culture supernatant of isolate N17-1 degraded AFB₁ effectively, whereas the viable cells and intra cell extracts were far less effective. Factors influencing AFB1 degradation by the culture supernatant were investigated. Maximum degradation was observed at 55 °C. Ions Mn²⁺ and Cu²⁺ were activators for AFB1 degradation, however, ions Mg²⁺, Li⁺, Zn²⁺, Se²⁺, Fe³⁺ were strong inhibitors. Treatments with proteinase K and proteinase K plus SDS significantly reduced the degradation activity of the culture supernatant. No degradation products were observed based on preliminary LC-QTOF/MS analysis, indicating AFB₁ was metabolized to degradation products with chemical properties different from that of AFB₁. The results indicated that the degradation of AFB₁ by P. aeruginosa N17-1 was enzymatic and could have a great potential in industrial applications. This is the first report indicating that the isolate of P. aeruginosa possesses the ability to degrade aflatoxin.

  3. Pseudomonas fluorescens' view of the periodic table.

    Science.gov (United States)

    Workentine, Matthew L; Harrison, Joe J; Stenroos, Pernilla U; Ceri, Howard; Turner, Raymond J

    2008-01-01

    Growth in a biofilm modulates microbial metal susceptibility, sometimes increasing the ability of microorganisms to withstand toxic metal species by several orders of magnitude. In this study, a high-throughput metal toxicity screen was initiated with the aim of correlating biological toxicity data in planktonic and biofilm cells to the physiochemical properties of metal ions. To this end, Pseudomonas fluorescens ATCC 13525 was grown in the Calgary Biofilm Device (CBD) and biofilms and planktonic cells of this microorganism were exposed to gradient arrays of different metal ions. These arrays included 44 different metals with representative compounds that spanned every group of the periodic table (except for the halogens and noble gases). The minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC) and minimum biofilm eradication concentration (MBEC) values were obtained after exposing the biofilms to metal ions for 4 h. Using these values, metal ion toxicity was correlated to the following ion-specific physicochemical parameters: standard reduction-oxidation potential, electronegativity, the solubility product of the corresponding metal-sulfide complex, the Pearson softness index, electron density and the covalent index. When the ions were grouped according to outer shell electron structure, we found that heavy metal ions gave the strongest correlations to these parameters and were more toxic on average than the other classes of the ions. Correlations were different for biofilms than for planktonic cells, indicating that chemical mechanisms of metal ion toxicity differ between the two modes of growth. We suggest that biofilms can specifically counter the toxic effects of certain physicochemical parameters, which may contribute to the increased ability of biofilms to withstand metal toxicity.

  4. Chromosomal organization and segregation in Pseudomonas aeruginosa.

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    Isabelle Vallet-Gely

    2013-05-01

    Full Text Available The study of chromosomal organization and segregation in a handful of bacteria has revealed surprising variety in the mechanisms mediating such fundamental processes. In this study, we further emphasized this diversity by revealing an original organization of the Pseudomonas aeruginosa chromosome. We analyzed the localization of 20 chromosomal markers and several components of the replication machinery in this important opportunistic γ-proteobacteria pathogen. This technique allowed us to show that the 6.3 Mb unique circular chromosome of P. aeruginosa is globally oriented from the old pole of the cell to the division plane/new pole along the oriC-dif axis. The replication machinery is positioned at mid-cell, and the chromosomal loci from oriC to dif are moved sequentially to mid-cell prior to replication. The two chromosomal copies are subsequently segregated at their final subcellular destination in the two halves of the cell. We identified two regions in which markers localize at similar positions, suggesting a bias in the distribution of chromosomal regions in the cell. The first region encompasses 1.4 Mb surrounding oriC, where loci are positioned around the 0.2/0.8 relative cell length upon segregation. The second region contains at least 800 kb surrounding dif, where loci show an extensive colocalization step following replication. We also showed that disrupting the ParABS system is very detrimental in P. aeruginosa. Possible mechanisms responsible for the coordinated chromosomal segregation process and for the presence of large distinctive regions are discussed.

  5. Responses of Pseudomonas aeruginosa to antimicrobials

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    Yuji eMorita

    2014-01-01

    Full Text Available Infections caused by Pseudomonas aeruginosa often are hard to treat; inappropriate chemotherapy readily selects multidrug-resistant P. aeruginosa. This organism can be exposed to a wide range of concentrations of antimicrobials during treatment; learning more about the responses of P. aeruginosa to antimicrobials is therefore important. We review here responses of the bacterium P. aeruginosa upon exposure to antimicrobials at levels below the inhibitory concentration.Carbapenems (e.g., imipenem have been shown to induce the formation of thicker and more robust biofilms, while fluoroquinolones (e.g., ciprofloxacin and aminoglycosides (e.g., tobramycin have been shown to induce biofilm formation. Ciprofloxacin also has been demonstrated to enhance the frequency of mutation to carbapenem resistance. Conversely, although macrolides (e.g., azithromycin typically are not effective against P. aeruginosa because of the pseudomonal outer-membrane impermeability and efflux, macrolides do lead to a reduction in virulence factor production. Similarly, tetracycline is not very effective against this organism, but is known to induce the type-III secretion system and consequently enhance cytotoxicity of P. aeruginosa in vivo. Of special note are the effects of antibacterials and disinfectants on pseudomonal efflux systems. Sub-inhibitory concentrations of protein synthesis inhibitors (aminoglycosides, tetracycline, chloramphenicol, etc. induce the MexXY multidrug efflux system. This response is known to be mediated by interference with the translation of the leader peptide PA5471.1, with consequent effects on expression of the PA5471 gene product. Additionally, induction of the MexCD-OprJ multidrug efflux system is observed upon exposure to sub-inhibitory concentrations of disinfectants such as chlorhexidine and benzalkonium. This response is known to be dependent upon the AlgU stress response factor.Altogether, these biological responses of P. aeruginosa

  6. Pseudomonas aeruginosa genomic structure and diversity

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    Jens eKlockgether

    2011-07-01

    Full Text Available The Pseudomonas aeruginosa genome (G + C content 65-67%, size 5.5 – 7 Mbp is made up of a single circular chromosome and a variable number of plasmids. Sequencing of complete genomes or blocks of the accessory genome has revealed that the genome encodes a large repertoire of transporters, transcriptional regulators and two-component regulatory systems which reflects its metabolic diversity to utilize a broad range of nutrients. The conserved core component of the genome is largely collinear among P. aeruginosa strains and exhibits an interclonal sequence diversity of 0.5 – 0.7%. Only a few loci of the core genome are subject to diversifying selection. Genome diversity is mainly caused by accessory DNA elements located in 79 regions of genome plasticity that are scattered around the genome and show an anomalous usage of mono- to tetradecanucleotides. Genomic islands of the pKLC102/PAGI-2 family that integrate into tRNALys or tRNAGly genes represent hotspots of inter- and intraclonal genomic diversity. The individual islands differ in their repertoire of metabolic genes that make a large contribution to the pangenome. In order to unravel intraclonal diversity of P. aeruginosa, the genomes of two members of the PA14 clonal complex from diverse habitats and geographic origin were compared. The genome sequences differed by less than 0.01% from each other. 198 of the 231 SNPs were non-randomly distributed in the genome. Non-synonymous SNPs were mainly found in an integrated Pf1-like phage and in genes involved in transcriptional regulation, membrane and extracellular constituents, transport and secretion. In summary, P. aeruginosa is endowed with a highly conserved core genome of low sequence diversity and a highly variable accessory genome that communicates with other pseudomonads and genera via horizontal gene transfer.

  7. Ambroxol interferes with Pseudomonas aeruginosa quorum sensing.

    Science.gov (United States)

    Lu, Qi; Yu, Jialin; Yang, Xiqiang; Wang, Jiarong; Wang, Lijia; Lin, Yayin; Lin, Lihua

    2010-09-01

    The mucolytic agent ambroxol has been reported to interfere with the formation of Pseudomonas aeruginosa-derived biofilms in addition to reducing alginate production by undefined mechanisms. Since quorum sensing is a key regulator of virulence and biofilm formation, we examined the effects of ambroxol on P. aeruginosa PAO1 wild-type bacterial clearance rates, adhesion profiles and biofilm formation compared with the quorum sensing-deficient, double-mutant strains DeltalasR DeltarhlR and DeltalasI DeltarhlI. Data presented in this report demonstrated that ambroxol treatment reduced survival rates of the double-mutant strains compared with the wild-type strain in a dose-dependent manner even though the double-mutants had increased adhesion in the presence of ambroxol compared with the wild-type strain. The PAO1 wild-type strain produced a significantly thicker biofilm (21.64+/-0.57 microm) compared with the biofilms produced by the DeltalasR DeltarhlR (7.36+/-0.2 microm) and DeltalasI DeltarhlI (6.62+/-0.31 microm) isolates. Ambroxol treatment reduced biofilm thickness, increased areal porosity, and decreased the average diffusion distance and textual entropy of wild-type and double-mutant strains. However, compared with the double-mutant strains, the changes observed for the wild-type strain were more clearly defined. Finally, ambroxol exhibited significant antagonistic quorum-sensing properties, suggesting that it could be adapted for use clinically in the treatment of cystic fibrosis and to reduce biofilm formation and in the colonisation of indwelling devices.

  8. Engineering Pseudomonas stutzeri as a biogeochemical biosensor

    Science.gov (United States)

    Boynton, L.; Cheng, H. Y.; Del Valle, I.; Masiello, C. A.; Silberg, J. J.

    2016-12-01

    Biogeochemical cycles are being drastically altered as a result of anthropogenic activities, such as the burning of fossil fuels and the industrial production of ammonia. We know microbes play a major part in these cycles, but the extent of their biogeochemical roles remains largely uncharacterized due to inadequacies with culturing and measurement. While metagenomics and other -omics methods offer ways to reconstruct microbial communities, these approaches can only give an indication of the functional roles of microbes in a community. These -omics approaches are rapidly being expanded to the point of outpacing our knowledge of functional genes, which highlights an inherent need for analytical methods that non-invasively monitor Earth's processes in real time. Here we aim to exploit synthetic biology methods in order to engineer a ubiquitous denitrifying microbe, Pseudomonas stutzeri that can act as a biosensor in soil and marine environments. By using an easily cultivated microbe that is also common in many environments, we hope to develop a tool that allows us to zoom in on specific aspects of the nitrogen cycle. In order to monitor processes occurring at the genetic level in environments that cannot be resolved with fluorescence-based methods, such as soils, we have developed a system that instead relies on gas production by engineered microbial biosensors. P. stutzeri has been successfully engineered to release a gas, methyl bromide, which can continuously and non-invasively be measured by GC-MS. Similar to using Green Fluorescent Protein, GFP, in the biological sciences, the gene controlling gas production can be linked to those involved in denitrification, thereby creating a quantifiable gas signal that is correlated with microbial activity in the soil. Synthetically engineered microbial biosensors could reveal key aspects of metabolism in soil systems and offer a tool for characterizing the scope and degree of microbial impact on major biogeochemical cycles.

  9. Esmolol: immunomodulator in pyelonephritis by Pseudomonas aeruginosa.

    Science.gov (United States)

    Dimopoulos, George; Theodorakopoulou, Maria; Armaganidis, Apostolos; Tzepi, Ira-Maria; Lignos, Michael; Giamarellos-Bourboulis, Evangelos J; Tsaganos, Thomas

    2015-09-01

    Based on previous animal studies showing promising immunomodulatory efficacy esmolol, a selective β1-blocker, it was assumed that administration of esmolol in experimental pyelonephritis by multidrug-resistant Pseudomonas aeruginosa would prolong survival and modulate immune response. Acute pyelonephritis was induced in 80 rabbits and assigned to eight groups receiving normal saline (controls), esmolol, amikacin, or both agents as pretreatment and as treatment. Blood was sampled for measurement of malondialdehyde and tumor necrosis factor alpha. Animals were followed up for survival, and after death quantitative tissue cultures were performed. The in vitro effect of esmolol on bacterial growth and on the oxidative burst of neutrophils of healthy controls and of sepsis patients was studied. Survival of pretreatment groups administered single esmolol or esmolol and amikacin was prolonged compared with that of controls (P = 0.018 and P = 0.014, respectively); likewise, survival of treatment groups administered single esmolol or both agents was prolonged compared with that of controls (P = 0.007 and P = 0.014, respectively). Circulating malondialdehyde was significantly lower in pretreated animals administered esmolol or esmolol and amikacin compared with that in controls and in treated animals administered both agents compared with in controls (P = 0.020). In these groups, the bacterial load of the lung was significantly lower compared with controls. Serum tumor necrosis factor alpha did not change. Amikacin was increased in serum of esmolol-treated animals at levels which inhibited the in vitro growth of the studied isolate. Esmolol did not modify the in vitro growth of P aeruginosa and the oxidative burst of neutrophils. It is concluded that esmolol prolonged survival after experimental infection by multidrug-resistant P aeruginosa. Survival benefit may be related with pleiotropic actions connected with modulation of pharmacokinetics and attenuation of inflammation

  10. Risk assessment of Pseudomonas aeruginosa in water.

    Science.gov (United States)

    Mena, Kristina D; Gerba, Charles P

    2009-01-01

    . 1986). Outbreaks have also been reported from exposure to P. aeruginosa in swimming pools and water slides. Although P. aeruginosa has a reputation for being resistant to disinfection, most studies show that it does not exhibit any marked resistance to the disinfectants used to treat drinking water such as chlorine, chloramines, ozone, or iodine. One author, however, did find it to be slightly more resistant to UV disinfection than most other bacteria (Wolfe 1990). Although much has been written about biofilms in the drinking water industry, very little has been reported regarding the role of P. aeruginosa in biofilms. Tap water appears to be a significant route of transmission in hospitals, from colonization of plumbing fixtures. It is still not clear if the colonization results from the water in the distribution system, or personnel use within the hospital. Infections and colonization can be significantly reduced by placement of filters on the water taps. The oral dose of P. aeruginosa required to establish colonization in a healthy subject is high (George et al. 1989a). During dose-response studies, even when subjects (mice or humans) were colonized via ingestion, there was no evidence of disease. P. aeruginosa administered by the aerosol route at levels of 10(7) cells did cause disease symptoms in mice, and was lethal in aerosolized doses of 10(9) cells. Aerosol dose-response studies have not been undertaken with human subjects. Human health risks associated with exposure to P. aeruginosa via drinking water ingestion were estimated using a four-step risk assessment approach. The risk of colonization from ingesting P. aeruginosa in drinking water is low. The risk is slightly higher if the subject is taking an antibiotic resisted by P. aeruginosa. The fact that individuals on ampicillin are more susceptible to Pseudomonas gastrointestinal infection probably results from suppression of normal intestinal flora, which would allow Pseudomonas to colonize. The process of

  11. Bacillus novalis sp. nov., Bacillus vireti sp. nov., Bacillus soli sp. nov., Bacillus bataviensis sp. nov. and Bacillus drentensis sp. nov., from the Drentse A grasslands.

    Science.gov (United States)

    Heyrman, Jeroen; Vanparys, Bram; Logan, Niall A; Balcaen, An; Rodríguez-Díaz, Marina; Felske, Andreas; De Vos, Paul

    2004-01-01

    A group of 42 isolates were isolated from the soil of several disused hay fields, in the Drentse A agricultural research area (The Netherlands), that were taken out of production at different times. The group represents hitherto-uncultured Bacillus lineages that have previously been found, by a non-cultural method, to be predominant in soil. The strains were subjected to a polyphasic taxonomic study, including (GTG)5-PCR, 16S rDNA sequence analysis, DNA-DNA hybridizations, DNA base-ratio determination, fatty acid analysis and morphological and biochemical characterization. By comparing the groupings obtained by (GTG)5-PCR and 16S rDNA sequence analysis, six clusters of similar strains could be recognized. A DNA-DNA relatedness study showed that these clusters represented five novel genospecies. Further analysis supported the proposal of five novel species in the genus Bacillus, namely Bacillus novalis sp. nov. (type strain IDA3307T=R-15439T=LMG 21837T=DSM 15603T), Bacillus vireti sp. nov. (type strain IDA3632T=R-15447T=LMG 21834T=DSM 15602T), Bacillus soli sp. nov. (type strain IDA0086T=R-16300T=LMG 21838T=DSM 15604T), Bacillus bataviensis sp. nov. (type strain IDA1115T=R-16315T=LMG 21833T=DSM 15601T) and Bacillus drentensis sp. nov. (type strain IDA1967T=R-16337T=LMG 21831T=DSM 15600T).

  12. Accessible chromatin structure permits factors Sp1 and Sp3 to regulate human TGFBI gene expression.

    Science.gov (United States)

    Lee, Jong-Joo; Park, Keunhee; Shin, Myeong Heon; Yang, Wook-Jin; Song, Min-Ji; Park, Joo-Hong; Yong, Tai-Soon; Kim, Eung Kweon; Kim, Hyoung-Pyo

    2011-06-03

    Transforming growth factor beta 1-induced (TGFBI) protein is an extracellular matrix (ECM) protein that is associated with other ECM proteins and functions as a ligand for various types of integrins. In this study, we investigated how human TGFBI expression is regulated in lung and breast cancer cells. We observed that the TGFBI promoter in A549 and MBA-MD-231 cells, which constitutively express TGFBI, existed in an open chromatin conformation associated with transcriptionally permissive histone modifications. Moreover, we found that TGFBI expression required Sp1 transcription elements that can bind transcription factors Sp1 and Sp3 in vitro. Occupancy of the TGFBI promoter by Sp1 and Sp3 in vivo was only observed in TGFBI-expressing cells, indicating that open chromatin conformation might facilitate the binding of Sp1 and Sp3 to the TGFBI promoter region. TGFBI promoter activity was impaired when Sp1 elements were mutated, but was increased when Sp1 or Sp3 factors was overexpressed. Furthermore, Sp1 inhibition in vivo by mithramycin A, as well as knockdown of Sp1 and/or Sp3 expression by short interfering RNA, significantly reduced TGFBI mRNA and protein levels. Thus, our data demonstrated that the expression of TGFBI is well correlated with chromatin conformation at the TGFBI promoter, and that factors Sp1 and Sp3 are the primary determinants for the control of constitutive expression of TGFBI gene. Copyright © 2011 Elsevier Inc. All rights reserved.

  13. Rapid adaptation drives invasion of airway donor microbiota by Pseudomonas after lung transplantation

    OpenAIRE

    M. Beaume; Köhler, T; Greub, G; Manuel, O; J-D. Aubert; Baerlocher, L.; Farinelli, L.; Buckling, A.; van Delden, C.

    2017-01-01

    In cystic fibrosis (CF) patients, chronic airway infection by Pseudomonas leads to progressive lung destruction ultimately requiring lung transplantation (LT). Following LT, CF-adapted Pseudomonas strains, potentially originating from the sinuses, may seed the allograft leading to infections and reduced allograft survival. We investigated whether CF-adapted Pseudomonas populations invade the donor microbiota and adapt to the non-CF allograft. We collected sequential Pseudomonas isolates and a...

  14. Biotransformation of Tributyltin chloride by Pseudomonas stutzeri strain DN2

    Directory of Open Access Journals (Sweden)

    Dnyanada S. Khanolkar

    2014-12-01

    Full Text Available A bacterial isolate capable of utilizing tributyltin chloride (TBTCl as sole carbon source was isolated from estuarine sediments of west coast of India and identified as Pseudomonas stutzeri based on biochemical tests and Fatty acid methyl ester (FAME analysis. This isolate was designated as strain DN2. Although this bacterial isolate could resist up to 3 mM TBTCl level, it showed maximum growth at 2 mM TBTCl in mineral salt medium (MSM. Pseudomonas stutzeri DN2 exposed to 2 mM TBTCl revealed significant alteration in cell morphology as elongation and shrinkage in cell size along with roughness of cell surface. FTIR and NMR analysis of TBTCl degradation product extracted using chloroform and purified using column chromatography clearly revealed biotransformation of TBTCl into Dibutyltin dichloride (DBTCl2 through debutylation process. Therefore, Pseudomonas stutzeri strain DN2 may be used as a potential bacterial strain for bioremediation of TBTCl contaminated aquatic environmental sites.

  15. Effects of ambroxol on alginate of mature Pseudomonas aeruginosa biofilms.

    Science.gov (United States)

    Li, Fang; Yu, Jialin; Yang, Hua; Wan, Zhenyan; Bai, Dan

    2008-07-01

    Biofilm-forming bacteria Pseudomonas aeruginosa is a common pathogen in mechanically ventilated newborns, which can cause life-threatening infections. Alginate of mucoid Pseudomonas aeruginosa biofilms is considered an important virulence factor which contributes to the resistance to antibiotics. Traditionally, ambroxol is widely used in newborns with lung problems as a mucolytic agent and antioxidant agent as well. And there are few studies that demonstrated the anti-biofilm activity of ambroxol. In this study, we found that ambroxol can affect the structure of mucoid Pseudomonas aeruginosa biofilms. Further, we found that ambroxol reduces the production of alginate, the expression of the important genes and the activity of key enzyme guanosine diphospho-D-mannose dehydrogenase (GDP-mannose dehydrogenase; GMD) which were involved in alginate biosynthesis.

  16. Subtilase SprP exerts pleiotropic effects in Pseudomonas aeruginosa.

    Science.gov (United States)

    Pelzer, Alexander; Polen, Tino; Funken, Horst; Rosenau, Frank; Wilhelm, Susanne; Bott, Michael; Jaeger, Karl-Erich

    2014-02-01

    The open reading frame PA1242 in the genome of Pseudomonas aeruginosa PAO1 encodes a putative protease belonging to the peptidase S8 family of subtilases. The respective enzyme termed SprP consists of an N-terminal signal peptide and a so-called S8 domain linked by a domain of unknown function (DUF). Presumably, this DUF domain defines a discrete class of Pseudomonas proteins as homologous domains can be identified almost exclusively in proteins of the genus Pseudomonas. The sprP gene was expressed in Escherichia coli and proteolytic activity was demonstrated. A P. aeruginosa ∆sprP mutant was constructed and its gene expression pattern compared to the wild-type strain by genome microarray analysis revealing altered expression levels of 218 genes. Apparently, SprP is involved in regulation of a variety of different cellular processes in P. aeruginosa including pyoverdine synthesis, denitrification, the formation of cell aggregates, and of biofilms.

  17. Biotransformation of Tributyltin chloride by Pseudomonas stutzeri strain DN2

    Science.gov (United States)

    Khanolkar, Dnyanada S.; Naik, Milind Mohan; Dubey, Santosh Kumar

    2014-01-01

    A bacterial isolate capable of utilizing tributyltin chloride (TBTCl) as sole carbon source was isolated from estuarine sediments of west coast of India and identified as Pseudomonas stutzeri based on biochemical tests and Fatty acid methyl ester (FAME) analysis. This isolate was designated as strain DN2. Although this bacterial isolate could resist up to 3 mM TBTCl level, it showed maximum growth at 2 mM TBTCl in mineral salt medium (MSM). Pseudomonas stutzeri DN2 exposed to 2 mM TBTCl revealed significant alteration in cell morphology as elongation and shrinkage in cell size along with roughness of cell surface. FTIR and NMR analysis of TBTCl degradation product extracted using chloroform and purified using column chromatography clearly revealed biotransformation of TBTCl into Dibutyltin dichloride (DBTCl2) through debutylation process. Therefore, Pseudomonas stutzeri strain DN2 may be used as a potential bacterial strain for bioremediation of TBTCl contaminated aquatic environmental sites. PMID:25763027

  18. Diversity and antibiotic resistance in Pseudomonas spp. from drinking water.

    Science.gov (United States)

    Vaz-Moreira, Ivone; Nunes, Olga C; Manaia, Célia M

    2012-06-01

    Pseudomonas spp. are common inhabitants of aquatic environments, including drinking water. Multi-antibiotic resistance in clinical isolates of P. aeruginosa is widely reported and deeply characterized. However, the information regarding other species and environmental isolates of this genus is scant. This study was designed based on the hypothesis that members of the genus Pseudomonas given their high prevalence, wide distribution in waters and genetic plasticity can be important reservoirs of antibiotic resistance in drinking water. With this aim, the diversity and antibiotic resistance phenotypes of Pseudomonas isolated from different drinking water sources were evaluated. The genotypic diversity analyses were based on six housekeeping genes (16S rRNA, rpoD, rpoB, gyrB, recA and ITS) and on pulsed field gel electrophoresis. Susceptibility to 21 antibiotics of eight classes was tested using the ATB PSE EU (08) and disk diffusion methods. Pseudomonas spp. were isolated from 14 of the 32 sampled sites. A total of 55 non-repetitive isolates were affiliated to twenty species. Although the same species were isolated from different sampling sites, identical genotypes were never observed in distinct types of water (water treatment plant/distribution system, tap water, cup fillers, biofilm, and mineral water). In general, the prevalence of antibiotic resistance was low and often the resistance patterns were related with the species and/or the strain genotype. Resistance to ticarcillin, ticarcillin with clavulanic acid, fosfomycin and cotrimoxazol were the most prevalent (69-84%). No resistance to piperacillin, levofloxacin, ciprofloxacin, tetracycline, gentamicin, tobramycin, amikacin, imipenem or meropenem was observed. This study demonstrates that Pseudomonas spp. are not so widespread in drinking water as commonly assumed. Nevertheless, it suggests that water Pseudomonas can spread acquired antibiotic resistance, preferentially via vertical transmission.

  19. Impaired Pulmonary Defense Against Pseudomonas aeruginosa in VEGF Gene Inactivated Mouse Lung

    Science.gov (United States)

    Breen, Ellen C.; Malloy, Jaret L.; Tang, Kechun; Xia, Feng; Fu, Zhenxing; Hancock, Robert E. W.; Overhage, Joerg; Wagner, Peter D.; Spragg, Roger G.

    2012-01-01

    Repeated bacterial and viral infections are known to contribute to worsening lung function in several respiratory diseases, including asthma, cystic fibrosis and chronic obstructive pulmonary disease (COPD). Previous studies have reported alveolar wall cell apoptosis and parenchymal damage in adult pulmonary VEGF gene ablated mice. We hypothesized that VEGF expressed by type II cells is also necessary to provide an effective host defense against bacteria in part by maintaining surfactant homeostasis. Therefore, Pseudomonas aeruginosa (PAO1) levels were evaluated in mice following lung-targeted VEGF gene inactivation, and alterations in VEGF-dependent type II cell function were evaluated by measuring surfactant homeostasis in mouse lungs and isolated type II cells. In VEGF-deficient lungs increased PAO1 levels and pro-inflammatory cytokines, TNFα and IL-6, were detected 24 hours after bacterial instillation compared to control lungs. In vivo lung-targeted VEGF gene deletion (57% decrease in total pulmonary VEGF) did not alter alveolar surfactant or tissue disaturated phosphatidylcholine (DSPC) levels. However, sphingomyelin content, choline phosphate cytidylyltransferase (CCT) mRNA and SP-D expression were decreased. In isolated type II cells an 80% reduction of VEGF protein resulted in decreases in total phospholipids (PL), DSPC, DSPC synthesis, surfactant associated proteins (SP)-B and -D, and the lipid transporters, ABCA1 and Rab3D. TPA-induced DSPC secretion and apoptosis were elevated in VEGF-deficient type II cells. These results suggest a potential protective role for type II cell-expressed VEGF against bacterial initiated infection. PMID:22718316

  20. Isolation of a strain of Pseudomonas putida capable of metabolizing anionic detergent sodium dodecyl sulfate (SDS

    Directory of Open Access Journals (Sweden)

    A Kumar

    2011-05-01

    Full Text Available Background and objectives: Sodium Dodecyl Sulfate (SDS is one of the most widely used anionic detergents. The present study deals with isolation and identification of SDS-degrading bacteria from a detergent contaminated pond situated in Varanasi city, India."nMaterials and Methods: Employing enrichment technique in minimal medium (PBM, SDS-degrading bacteria were isolated from pond water sample. Rate of degradation of SDS was studied in liquid PBM and also degradation of different concentrations of SDS was also studied to find out maximum concentration of SDS degraded by the potent isolates. Alkyl sulfatase activity (key enzyme in SDS degradation was estimated in crude cell extracts and multiplicity of alkyl sulfatase was studied by Native PAGE Zymography. The potent isolate was identified by 16S rRNA sequence analysis."nResults: Using enrichment technique in minimal medium containing SDS as a sole carbon source, initially three SDS degrading isolates were recovered. However, only one isolate, SP3, was found to be an efficient degrader of SDS. It was observed that this strain could completely metabolize 0.1% SDS in 16 h, 0.2% SDS in 20 h and 0.3% SDS in 24 h of incubation. Specific activity of alkyl sulfatase was 0.087±0.004 μmol SDS/mg protein/min and Native PAGE Zymography showed presence of alkyl sulfatase of Rf value of 0.21. This isolate was identified as Pseudomonas putida strain SP3."nConclusion: This is the report of isolation of SDS-degrading strain of P. putida, which shows high rate of SDS degradation and can degrade up to 0.3% SDS. It appears that this isolate can be exploited for bioremediation of this detergent from water systems.