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Sample records for arthrobacter nitroguajacolicus ru61a

  1. [Genomics basis of Arthrobacter spp. environmental adaptability– A review].

    Science.gov (United States)

    Zhang, Xinjian; Zhang, Guangzhi; Yang, Hetong

    2016-04-04

    Arthrobacter species are found ecologically diverse and can survive in various environments. Many strains of these species have metabolic versatility and can degrade many environmental pollutants. Arthrobacter species are thought to play important roles in catabolism of environmental pollutants in nature. In recent years, the genomes of many Arthrobacter strains have been sequenced, which provides comprehensive information to clarify the molecular mechanisms related to environmental adaptability of Arthrobacter species. These genomics findings revealed several features that are commonly observed in Arthrobacter strains allowing for survival under stressful conditions. These include an array of genes associated with sigma factors and responses to oxidative, osmotic, starvation and temperature stresses. The genomics basis of their environmental adaptability are reviewed, which is expected to provide useful information for applying Arthrobacter strains in pollution remediation and shed some light on other bacterial environmental adaptability researches.

  2. Complete Genome Sequences of 44 Arthrobacter Phages.

    Science.gov (United States)

    Klyczek, Karen K; Jacobs-Sera, Deborah; Adair, Tamarah L; Adams, Sandra D; Ball, Sarah L; Benjamin, Robert C; Bonilla, J Alfred; Breitenberger, Caroline A; Daniels, Charles J; Gaffney, Bobby L; Harrison, Melinda; Hughes, Lee E; King, Rodney A; Krukonis, Gregory P; Lopez, A Javier; Monsen-Collar, Kirsten; Pizzorno, Marie C; Rinehart, Claire A; Staples, Amanda K; Stowe, Emily L; Garlena, Rebecca A; Russell, Daniel A; Cresawn, Steven G; Pope, Welkin H; Hatfull, Graham F

    2018-02-01

    We report here the complete genome sequences of 44 phages infecting Arthrobacter sp. strain ATCC 21022. These phages have double-stranded DNA genomes with sizes ranging from 15,680 to 70,707 bp and G+C contents from 45.1% to 68.5%. All three tail types (belonging to the families Siphoviridae , Myoviridae , and Podoviridae ) are represented. Copyright © 2018 Klyczek et al.

  3. Four novel Arthrobacter species isolated from filtration substrate.

    Science.gov (United States)

    Ding, Linxian; Hirose, Taketo; Yokota, Akira

    2009-04-01

    Four Gram-positive, non-motile, non-spore-forming bacterial strains, LC4(T), LC6(T), LC10(T) and LC13(T), were isolated from a filtration substrate made from trass, a volcanic rock, and their taxonomic positions were investigated by a polyphasic taxonomic approach. The novel strains grew over a temperature range of 5-40 degrees C, at pH values of 6-11 and in the presence of 3-7 % (w/v) NaCl. A phylogenetic tree based on 16S rRNA gene sequences showed the novel strains formed a distinct evolutionary lineage within the genus Arthrobacter. Chemotaxonomic analyses demonstrated that the major menaquinone was MK-9(H(2)), a menaquinone typical of the Arthrobacter globiformis group. The major fatty acid was anteiso-C(15 : 0) and the major amino acid present in the cell-wall peptidoglycan was l-lysine. These observations supported the affiliation of the novel strains to the genus Arthrobacter. On the basis of their morphological, physiological and genotypic characteristics, the new isolates are considered to represent four novel species of the genus Arthrobacter, for which the names Arthrobacter niigatensis sp. nov. (type strain LC4(T)=IAM 15382(T)=CCTCC AB 206012(T)), Arthrobacter alkaliphilus sp. nov. (type strain LC6(T)=IAM 15383(T)=CCTCC AB 206013(T)), Arthrobacter echigonensis sp. nov. (type strain LC10(T)=IAM 15385(T)=CCTCC AB 206017(T)) and Arthrobacter albidus sp. nov. (type strain LC13(T)=IAM 15386(T)=CCTCC AB 206018(T)) are proposed.

  4. Production of d-Tagatose from Dulcitol by Arthrobacter globiformis

    OpenAIRE

    Izumori, Ken; Miyoshi, Tatsuji; Tokuda, Sachiko; Yamabe, Keizo

    1984-01-01

    A process for the bacterial oxidation of dulcitol to d-tagatose has been developed. The strain Arthrobacter globiformis ST48 used in this fermentation was isolated from soil. The yield of d-tagatose accumulated in the medium from dulcitol was as high as 85%. About 14 g of d-tagatose crystals was isolated from 1 liter of 2% dulcitol medium.

  5. Production of d-Tagatose from Dulcitol by Arthrobacter globiformis

    Science.gov (United States)

    Izumori, Ken; Miyoshi, Tatsuji; Tokuda, Sachiko; Yamabe, Keizo

    1984-01-01

    A process for the bacterial oxidation of dulcitol to d-tagatose has been developed. The strain Arthrobacter globiformis ST48 used in this fermentation was isolated from soil. The yield of d-tagatose accumulated in the medium from dulcitol was as high as 85%. About 14 g of d-tagatose crystals was isolated from 1 liter of 2% dulcitol medium. PMID:16346663

  6. Xylanolytic enzyme systems in Arthrobacter sp MTCC 5214 and Lactobacillus sp.

    Digital Repository Service at National Institute of Oceanography (India)

    Khandeparker, R.; Jalal, T.

    The production of extracellular xylanolytic enzymes such as xylanase, alfa-L-arabinofuranosidase (alfa-l-AFase), and acetyl xylan esterase (Axe) by marine Arthrobacter sp and Lactobacillus sp was investigated using different carbon sources Induction...

  7. Degradation of the Phosphonate Herbicide Glyphosate by Arthrobacter atrocyaneus ATCC 13752

    OpenAIRE

    Pipke, Rüdiger; Amrhein, Nikolaus

    1988-01-01

    Of nine authentic Arthrobacter strains tested, only A. atrocyaneus ATCC 13752 was capable of using the herbicide glyphosate [N-(phosphonomethyl)glycine] as its sole source of phosphorus. Contrary to the previously isolated Arthrobacter sp. strain GLP-1, which degrades glyphosate via sarcosine, A. atrocyaneus metabolized glyphosate to aminomethylphosphonic acid. The carbon of aminomethylphosphonic acid was entirely converted to CO2. This is the first report on glyphosate degradation by a bacte...

  8. Application of NAA Method to Study Chromium Uptake by Arthrobacter oxydans

    CERN Document Server

    Tsibakhashvili, N Ya; Kalabegishvili, T L; Kirkesali, E I; Frontasyeva, M V; Pomyakushina, E V; Pavlov, S S

    2002-01-01

    To study chromium uptake by Arthrobacter oxydans (Cr(VI)-reducer bacteria isolated from Columbia basalt rocks, USA) instrumental neutron activation analysis method was applied. It was established that chromate accumulation is dose-dependent and it is more intesive in the interval of concentrations of Cr(VI) (10-50 mg/l). At low concentrations of Cr(VI) (up to 50 mg/l) the most intensive formation of Cr(V) was also found (using ESR method). Besides, it was estimated that reduction from Cr(VI) to Cr(V) is faster process than the uptake of Cr(VI). According to ENAA measurements Cr(III), in constant to Cr(VI), is not accumulated in Arthrobacter oxydans cells up to concentration of 200 mg/l. Using epithermal neutron activation analysis the background levels of 17 major, minor and trace elements were determined in Arthrobacter oxydans.

  9. Produksi, isolasi dan karakterisasi enzim dekstranase dari Arthrobacter sp. B7

    Directory of Open Access Journals (Sweden)

    Afaf Baktir

    2012-02-01

    Full Text Available Dextranase enzyme has been purified and characterized from Arthrobacter sp. B7. This enzyme was purified from the culture supernatant of Arthrobacter sp. B7 by procedure of native PAGE. The molecular size of the enzyme was estimated 72,5 kDa by SDSPAGE. The N-terminal amino acid sequence of this enzyme determined using Edman degradation techniques were APVTADVGNLHT. SDS-PAGE and native-PAGE analysis revealed that the enzyme molecule consisted of one sub-unit.

  10. Potential Degradation of Swainsonine by Intracellular Enzymes of Arthrobacter sp. HW08

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    Haili Li

    2013-11-01

    Full Text Available Swainsonine (SW is a toxin produced by locoweeds and harmful to the livestock industry. Degrading SW by Arthrobacter sp. HW08 was demonstrated as a promising way to deal with SW poisoning. However, it is unknown which part of the subcellular enzymes in Arthrobacter sp. HW08 is responsible for biodegrading SW and whether the metabolites are atoxic. In this study, intracellular and extracellular enzymes of Arthrobacter sp. HW08 were isolated and their enzyme activity was evaluated. The metabolites were fed to mice, and physiological and histological properties of the treated mice were investigated. The results showed that only intracellular enzyme of Arthrobacter sp. HW08 (IEHW08 could degrade SW efficiently. Compared with mice in SW treatment group, mice in SW + IEHW08 treatment group (1 increased their body weights; (2 showed higher number of platelets and lower number of white blood cells; (3 decreased the levels of creatinine, urea nitrogen, alanine transaminase and aspartate aminotransferase in serum; (4 reduced the number of vacuolated cells in cerebellum, liver and kidney. All these data demonstrate that IEHW08 was potentially safe for mice, while keeping the capacity of degrading SW. This study indicates a possible application of IEHW08 as an additive in the livestock industry to protect animals from SW poisoning.

  11. CLONING AND CHARACTERIZATION OF THE PHTHALATE CATABOLISM REGION OF PRE1 OF ARTHROBACTER KEYSERI 12B

    Science.gov (United States)

    o-Phthalate (benzene-1,2-dicarboxylate) is a central intermediate in the bacterial degradation of phthalate ester plasticizers as well as of a number of fused-ring polycyclic aromatic hydrocarbons found in fossil fuels. In Arthrobacter keyseri 12B, the genes encoding catabolism o...

  12. Flocculating performance of a bioflocculant produced by Arthrobacter humicola in sewage waste water treatment.

    Science.gov (United States)

    Agunbiade, Mayowa Oladele; Van Heerden, Esta; Pohl, Carolina H; Ashafa, Anofi Tom

    2017-06-12

    The discharge of poorly treated effluents into the environment has far reaching, consequential impacts on human and aquatic life forms. Thus, we evaluated the flocculating efficiency of our test bioflocculant and we report for the first time the ability of the biopolymeric flocculant produced by Arthrobacter humicola in the treatment of sewage wastewater. This strain was isolated from sediment soil sample at Sterkfontein dam in the Eastern Free State province of South Africa. Basic Local Alignment Search Tool (BLAST) analysis of the nucleotide sequence of the 16S rDNA revealed the bacteria to have 99% similarity to Arthrobacter humicola strain R1 and the sequence was deposited in the Gene bank as Arthrobacter humicola with accession number KC816574.1. Flocculating activity was enhanced with the aid of divalent cations, pH 12, at a dosage concentration of 0.8 mg/mL. The purified bioflocculant was heat stable and could retain more than 78% of its flocculating activity after heating at 100 °C for 25 min. Fourier Transform Infrared Spectroscopy analysis demonstrated the presence of hydroxyl and carboxyl moieties as the functional groups. The thermogravimetric analysis was used to monitor the pyrolysis profile of the purified bioflocculant and elemental composition revealed C: O: Na: P: K with 13.90: 41.96: 26.79: 16.61: 0.74 weight percentage respectively. The purified bioflocculant was able to remove chemical oxygen demand, biological oxygen demand, suspended solids, nitrate and turbidity from sewage waste water at efficiencies of 65.7%, 63.5%, 55.7%, 71.4% and 81.3% respectively. The results of this study indicate the possibility of using the bioflocculant produced by Arthrobacter humicola as a potential alternative to synthesized chemical flocculants in sewage waste water treatment and other industrial waste water.

  13. Impact of phenolic substrate and growth temperature on the arthrobacter chlorophenolicus proteome

    Energy Technology Data Exchange (ETDEWEB)

    Unell, Maria; Abraham, Paul E.; Shah, Manesh; Zhang, Bing; Ruckert, Christian; VerBerkmoes, Nathan C.; Jansson, Janet K.

    2009-02-15

    We compared the Arthrobacter chlorophenolicus proteome during growth on 4-chlorophenol, 4-nitrophenol or phenol at 5 C and 28 C; both for the wild type and a mutant strain with mass spectrometry based proteomics. A label free workflow employing spectral counting identified 3749 proteins across all growth conditions, representing over 70% of the predicted genome and 739 of these proteins form the core proteome. Statistically significant differences were found in the proteomes of cells grown under different conditions including differentiation of hundreds of unknown proteins. The 4-chlorophenol-degradation pathway was confirmed, but not that for phenol.

  14. Degradation of 2,4,6-Trinitrophenol (TNP) by Arthrobacter sp. HPC1223 Isolated from Effluent Treatment Plant

    OpenAIRE

    Qureshi, Asifa; Kapley, Atya; Purohit, Hemant J.

    2012-01-01

    Arthrobacter sp. HPC1223 (Genebank Accession No. AY948280) isolated from activated biomass of effluent treatment plant was capable of utilizing 2,4,6 trinitrophenol (TNP) under aerobic condition at 30 °C and pH 7 as nitrogen source. It was observed that the isolated bacteria utilized TNP up to 70 % (1 mM) in R2A media with nitrite release. The culture growth media changed into orange-red color hydride-meisenheimer complex at 24 h as detected by HPLC. Oxygen uptake of Arthrobacter HPC1223 towa...

  15. Tales of diversity: Genomic and morphological characteristics of forty-six Arthrobacter phages.

    Directory of Open Access Journals (Sweden)

    Karen K Klyczek

    Full Text Available The vast bacteriophage population harbors an immense reservoir of genetic information. Almost 2000 phage genomes have been sequenced from phages infecting hosts in the phylum Actinobacteria, and analysis of these genomes reveals substantial diversity, pervasive mosaicism, and novel mechanisms for phage replication and lysogeny. Here, we describe the isolation and genomic characterization of 46 phages from environmental samples at various geographic locations in the U.S. infecting a single Arthrobacter sp. strain. These phages include representatives of all three virion morphologies, and Jasmine is the first sequenced podovirus of an actinobacterial host. The phages also span considerable sequence diversity, and can be grouped into 10 clusters according to their nucleotide diversity, and two singletons each with no close relatives. However, the clusters/singletons appear to be genomically well separated from each other, and relatively few genes are shared between clusters. Genome size varies from among the smallest of siphoviral phages (15,319 bp to over 70 kbp, and G+C contents range from 45-68%, compared to 63.4% for the host genome. Although temperate phages are common among other actinobacterial hosts, these Arthrobacter phages are primarily lytic, and only the singleton Galaxy is likely temperate.

  16. Hexavalent chromate reduction during growth and by immobilized cells of arthrobacter sp. suk 1205

    International Nuclear Information System (INIS)

    Dey, S.; Paul, A.K.

    2017-01-01

    The chromate reducing actinomycetes, Arthrobacter sp. SUK 1205, isolated from chromite mine overburden of Odisha, India exhibited significant chromate reduction during growth with characteristic formation of pale green insoluble precipitate. Reduction of chromate increased with increase in inoculum density but the reduction potential declined as and when Cr(VI) concentration in the medium was increased. Chromate reducing efficiency was promoted when glycerol and glucose were used as electron donors and pH and temperature were maintained at 7.0 and 35 degree C, respectively. The reduction process was inhibited by several metal ions and metabolic inhibitors but not by Cu(II), Mn(II) and DNP. Among the matrices tested for whole cell immobilization, Ca-alginate immobilized whole cells were found to be most effective and were comparable with non-immobilized cells. Minimal salts (MS) medium was the most effective base for Cr(VI) reduction studies with immobilized cells. Under such conditions, the immobilized cells retained their enzymatic activity at least for 4 consecutive cycles indicating the potential of Arthrobacter sp. SUK 1205 in bioremediation of environmental chromium pollution. (author)

  17. Tales of diversity: Genomic and morphological characteristics of forty-six Arthrobacter phages.

    Science.gov (United States)

    Klyczek, Karen K; Bonilla, J Alfred; Jacobs-Sera, Deborah; Adair, Tamarah L; Afram, Patricia; Allen, Katherine G; Archambault, Megan L; Aziz, Rahat M; Bagnasco, Filippa G; Ball, Sarah L; Barrett, Natalie A; Benjamin, Robert C; Blasi, Christopher J; Borst, Katherine; Braun, Mary A; Broomell, Haley; Brown, Conner B; Brynell, Zachary S; Bue, Ashley B; Burke, Sydney O; Casazza, William; Cautela, Julia A; Chen, Kevin; Chimalakonda, Nitish S; Chudoff, Dylan; Connor, Jade A; Cross, Trevor S; Curtis, Kyra N; Dahlke, Jessica A; Deaton, Bethany M; Degroote, Sarah J; DeNigris, Danielle M; DeRuff, Katherine C; Dolan, Milan; Dunbar, David; Egan, Marisa S; Evans, Daniel R; Fahnestock, Abby K; Farooq, Amal; Finn, Garrett; Fratus, Christopher R; Gaffney, Bobby L; Garlena, Rebecca A; Garrigan, Kelly E; Gibbon, Bryan C; Goedde, Michael A; Guerrero Bustamante, Carlos A; Harrison, Melinda; Hartwell, Megan C; Heckman, Emily L; Huang, Jennifer; Hughes, Lee E; Hyduchak, Kathryn M; Jacob, Aswathi E; Kaku, Machika; Karstens, Allen W; Kenna, Margaret A; Khetarpal, Susheel; King, Rodney A; Kobokovich, Amanda L; Kolev, Hannah; Konde, Sai A; Kriese, Elizabeth; Lamey, Morgan E; Lantz, Carter N; Lapin, Jonathan S; Lawson, Temiloluwa O; Lee, In Young; Lee, Scott M; Lee-Soety, Julia Y; Lehmann, Emily M; London, Shawn C; Lopez, A Javier; Lynch, Kelly C; Mageeney, Catherine M; Martynyuk, Tetyana; Mathew, Kevin J; Mavrich, Travis N; McDaniel, Christopher M; McDonald, Hannah; McManus, C Joel; Medrano, Jessica E; Mele, Francis E; Menninger, Jennifer E; Miller, Sierra N; Minick, Josephine E; Nabua, Courtney T; Napoli, Caroline K; Nkangabwa, Martha; Oates, Elizabeth A; Ott, Cassandra T; Pellerino, Sarah K; Pinamont, William J; Pirnie, Ross T; Pizzorno, Marie C; Plautz, Emilee J; Pope, Welkin H; Pruett, Katelyn M; Rickstrew, Gabbi; Rimple, Patrick A; Rinehart, Claire A; Robinson, Kayla M; Rose, Victoria A; Russell, Daniel A; Schick, Amelia M; Schlossman, Julia; Schneider, Victoria M; Sells, Chloe A; Sieker, Jeremy W; Silva, Morgan P; Silvi, Marissa M; Simon, Stephanie E; Staples, Amanda K; Steed, Isabelle L; Stowe, Emily L; Stueven, Noah A; Swartz, Porter T; Sweet, Emma A; Sweetman, Abigail T; Tender, Corrina; Terry, Katrina; Thomas, Chrystal; Thomas, Daniel S; Thompson, Allison R; Vanderveen, Lorianna; Varma, Rohan; Vaught, Hannah L; Vo, Quynh D; Vonberg, Zachary T; Ware, Vassie C; Warrad, Yasmene M; Wathen, Kaitlyn E; Weinstein, Jonathan L; Wyper, Jacqueline F; Yankauskas, Jakob R; Zhang, Christine; Hatfull, Graham F

    2017-01-01

    The vast bacteriophage population harbors an immense reservoir of genetic information. Almost 2000 phage genomes have been sequenced from phages infecting hosts in the phylum Actinobacteria, and analysis of these genomes reveals substantial diversity, pervasive mosaicism, and novel mechanisms for phage replication and lysogeny. Here, we describe the isolation and genomic characterization of 46 phages from environmental samples at various geographic locations in the U.S. infecting a single Arthrobacter sp. strain. These phages include representatives of all three virion morphologies, and Jasmine is the first sequenced podovirus of an actinobacterial host. The phages also span considerable sequence diversity, and can be grouped into 10 clusters according to their nucleotide diversity, and two singletons each with no close relatives. However, the clusters/singletons appear to be genomically well separated from each other, and relatively few genes are shared between clusters. Genome size varies from among the smallest of siphoviral phages (15,319 bp) to over 70 kbp, and G+C contents range from 45-68%, compared to 63.4% for the host genome. Although temperate phages are common among other actinobacterial hosts, these Arthrobacter phages are primarily lytic, and only the singleton Galaxy is likely temperate.

  18. The rhizosphere microbiome of burned holm-oak: potential role of the genus Arthrobacter in the recovery of burned soils.

    Science.gov (United States)

    Fernández-González, Antonio J; Martínez-Hidalgo, Pilar; Cobo-Díaz, José F; Villadas, Pablo J; Martínez-Molina, Eustoquio; Toro, Nicolás; Tringe, Susannah G; Fernández-López, Manuel

    2017-07-20

    After a forest wildfire, the microbial communities have a transient alteration in their composition. The role of the soil microbial community in the recovery of an ecosystem following such an event remains poorly understood. Thus, it is necessary to understand the plant-microbe interactions that occur in burned soils. By high-throughput sequencing, we identified the main bacterial taxa of burnt holm-oak rhizosphere, then we obtained an isolate collection of the most abundant genus and its growth promoting activities were characterised. 16S rRNA amplicon sequencing showed that the genus Arthrobacter comprised more than 21% of the total community. 55 Arthrobacter strains were isolated and characterized using RAPDs and sequencing of the almost complete 16S rRNA gene. Our results indicate that isolated Arthrobacter strains present a very high genetic diversity, and they could play an important ecological role in interaction with the host plant by enhancing aerial growth. Most of the selected strains exhibited a great ability to degrade organic polymers in vitro as well as possibly presenting a direct mechanism for plant growth promotion. All the above data suggests that Arthrobacter can be considered as an excellent PGP rhizobacterium that may play an important role in the recovery of burned holm-oak forests.

  19. Optimization of cultural conditions for growth associated chromate reduction by Arthrobacter sp. SUK 1201 isolated from chromite mine overburden

    Energy Technology Data Exchange (ETDEWEB)

    Dey, Satarupa, E-mail: dey1919@gmail.com [Microbiology Laboratory, Department of Botany, University of Calcutta, Kolkata 700019 (India); Paul, A.K., E-mail: amalk_paul@yahoo.co.in [Microbiology Laboratory, Department of Botany, University of Calcutta, Kolkata 700019 (India)

    2012-04-30

    Highlights: Black-Right-Pointing-Pointer Isolation of a potent Cr(VI) resistant and reducing Arthrobacter SUK 1201 from chromite mine overburdens of Orissa, India. Black-Right-Pointing-Pointer Phylogenetically (16S rDNA analysis), Arthrobacter SUK 1201 showed 99% nucleotide base pair similarity with Arthrobacter GZK-1. Black-Right-Pointing-Pointer Production of insoluble chromium precipitates during chromate reduction under batch culture by the isolate SUK 1201. Black-Right-Pointing-Pointer Confirmation of formation of insoluble chromium precipitate during reduction studies by EDX analysis. Black-Right-Pointing-Pointer Optimization of cultural conditions for Cr(VI) reduction under batch culture leading to complete reduction of 2 mM of Cr(VI). - Abstract: Arthrobacter sp. SUK 1201, a chromium resistant and reducing bacterium having 99% sequence homology of 16S rDNA with Arthrobacter sp. GZK-1 was isolated from chromite mine overburden dumps of Orissa, India. The objective of the present study was to optimize the cultural conditions for chromate reduction by Arthrobacter sp. SUK 1201. The strain showed 67% reduction of 2 mM chromate in 7 days and was associated with the formation of green insoluble precipitate, which showed characteristic peak of chromium in to energy dispersive X-ray analysis. However, Fourier transform infrared spectra have failed to detect any complexation of end products of Cr(VI) reduction with the cell mass. Reduction of chromate increased with increased cell density and was maximum at 10{sup 10} cells/ml, but the reduction potential decreased with increase in Cr(VI) concentration. Chromate reducing efficiency was promoted when glycerol and glucose was used as electron donors. Optimum pH and temperature of Cr(VI) reduction was 7.0 and 35 Degree-Sign C respectively. The reduction process was inhibited by several metal ions and metabolic inhibitors but not by Cu(II) and DNP. These findings suggest that Arthrobacter sp. SUK 1201 has great promise

  20. Biosynthesis of NAD from nicotinic acid and nicotinamide by resting cells of Arthrobacter globiformis

    International Nuclear Information System (INIS)

    Kuwahara, Masaaki

    1978-01-01

    Isotopically labeled nicotinic acid and nicotinamide were incorporated into the metabolites of nicotinic acid-dependent pathway (Preiss-Handler pathway) of the NAD biosynthesis by resting cells of Arthrobacter globiformis. Azaserine and adenosine markedly stimulated the accumulation of NAD in the cells. Radioactive nicotinic acid and nicotinamide were also incorporated into an unknown compound when the cells were incubated in the presence of azaserine. Cell-free extract of the organism showed the NAD synthetase activity, which required ammonium ion and ATP for the amidation of deamido-NAD. Adenosine inhibited the enzyme activity. The organism possessed nicotinamidase, suggesting deamidation is the first step in the biosynthesis of NAD from nicotinamide. The activity was inhibited by NAD, NADP and NMN. (auth.)

  1. The Potency of Dextranase from Arthrobacter sp. Strain B7 as Dental Plaque Removal

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    AFAF BAKTIR

    2005-12-01

    Full Text Available Dextranase of Arthrobacter sp. strain B7 (B7DEX enzyme was characterized in this study. This enzyme hydrolyzed sucrose and dextran, but not other glucans (starch, nigeran, cellulose, -soluble glucan. It also hydrolyzed glucan from dental plaque with the activity of 7.38 + 0.66 U/ml, where the activity toward dextran was 31.88 + 1.24 U/ml. The enzyme exhibited the pH optimum of 7 and the temperature optimum of 50 oC. Its optimum stability was at pH 7 and 50 oC. The enzyme was inhibited by Fe3+, Cu2+, Zn2+, and Ag+, but not by the anionic detergent (SDS and the nonionic detergent (Triton-X. The enzyme was activated by Ca2+, Na+, Mg2+, and saliva.

  2. Potensi Enzim Dekstranase dari Arthrobacter sp. Galur B7 sebagai Penghambat Plak Gigi

    Directory of Open Access Journals (Sweden)

    AFAF BAKTIR

    2005-12-01

    Full Text Available Dextranase of Arthrobacter sp. strain B7 (B7DEX enzyme was characterized in this study. This enzyme hydrolyzed sucrose and dextran, but not other glucans (starch, nigeran, cellulose, β-soluble glucan. It also hydrolyzed glucan from dental plaque with the activity of 7.38 ± 0.66 U/ml, where the activity toward dextran was 31.88 ± 1.24 U/ml. The enzyme exhibited the pH optimum of 7 and the temperature optimum of 50 °C. Its optimum stability was at pH 7 and 50 °C. The enzyme was inhibited by Fe3+, Cu2+, Zn2+, and Ag+, but not by the anionic detergent (SDS and the nonionic detergent (Triton-X. The enzyme was activated by Ca2+, Na+, Mg2+, and saliva.

  3. A method for the production of D-tagatose using a recombinant Pichia pastoris strain secreting β-D-galactosidase from Arthrobacter chlorophenolicus and a recombinant L-arabinose isomerase from Arthrobacter sp. 22c.

    Science.gov (United States)

    Wanarska, Marta; Kur, Józef

    2012-08-23

    D-Tagatose is a natural monosaccharide which can be used as a low-calorie sugar substitute in food, beverages and pharmaceutical products. It is also currently being tested as an anti-diabetic and obesity control drug. D-Tagatose is a rare sugar, but it can be manufactured by the chemical or enzymatic isomerization of D-galactose obtained by a β-D-galactosidase-catalyzed hydrolysis of milk sugar lactose and the separation of D-glucose and D-galactose. L-Arabinose isomerases catalyze in vitro the conversion of D-galactose to D-tagatose and are the most promising enzymes for the large-scale production of D-tagatose. In this study, the araA gene from psychrotolerant Antarctic bacterium Arthrobacter sp. 22c was isolated, cloned and expressed in Escherichia coli. The active form of recombinant Arthrobacter sp. 22c L-arabinose isomerase consists of six subunits with a combined molecular weight of approximately 335 kDa. The maximum activity of this enzyme towards D-galactose was determined as occurring at 52°C; however, it exhibited over 60% of maximum activity at 30°C. The recombinant Arthrobacter sp. 22c L-arabinose isomerase was optimally active at a broad pH range of 5 to 9. This enzyme is not dependent on divalent metal ions, since it was only marginally activated by Mg2+, Mn2+ or Ca2+ and slightly inhibited by Co2+ or Ni2+. The bioconversion yield of D-galactose to D-tagatose by the purified L-arabinose isomerase reached 30% after 36 h at 50°C. In this study, a recombinant Pichia pastoris yeast strain secreting β-D-galactosidase Arthrobacter chlorophenolicus was also constructed. During cultivation of this strain in a whey permeate, lactose was hydrolyzed and D-glucose was metabolized, whereas D-galactose was accumulated in the medium. Moreover, cultivation of the P. pastoris strain secreting β-D-galactosidase in a whey permeate supplemented with Arthrobacter sp. 22c L-arabinose isomerase resulted in a 90% yield of lactose hydrolysis, the complete utilization

  4. A method for the production of D-tagatose using a recombinant Pichia pastoris strain secreting β-D-galactosidase from Arthrobacter chlorophenolicus and a recombinant L-arabinose isomerase from Arthrobacter sp. 22c

    Directory of Open Access Journals (Sweden)

    Wanarska Marta

    2012-08-01

    Full Text Available Abstract Background D-Tagatose is a natural monosaccharide which can be used as a low-calorie sugar substitute in food, beverages and pharmaceutical products. It is also currently being tested as an anti-diabetic and obesity control drug. D-Tagatose is a rare sugar, but it can be manufactured by the chemical or enzymatic isomerization of D-galactose obtained by a β-D-galactosidase-catalyzed hydrolysis of milk sugar lactose and the separation of D-glucose and D-galactose. L-Arabinose isomerases catalyze in vitro the conversion of D-galactose to D-tagatose and are the most promising enzymes for the large-scale production of D-tagatose. Results In this study, the araA gene from psychrotolerant Antarctic bacterium Arthrobacter sp. 22c was isolated, cloned and expressed in Escherichia coli. The active form of recombinant Arthrobacter sp. 22c L-arabinose isomerase consists of six subunits with a combined molecular weight of approximately 335 kDa. The maximum activity of this enzyme towards D-galactose was determined as occurring at 52°C; however, it exhibited over 60% of maximum activity at 30°C. The recombinant Arthrobacter sp. 22c L-arabinose isomerase was optimally active at a broad pH range of 5 to 9. This enzyme is not dependent on divalent metal ions, since it was only marginally activated by Mg2+, Mn2+ or Ca2+ and slightly inhibited by Co2+ or Ni2+. The bioconversion yield of D-galactose to D-tagatose by the purified L-arabinose isomerase reached 30% after 36 h at 50°C. In this study, a recombinant Pichia pastoris yeast strain secreting β-D-galactosidase Arthrobacter chlorophenolicus was also constructed. During cultivation of this strain in a whey permeate, lactose was hydrolyzed and D-glucose was metabolized, whereas D-galactose was accumulated in the medium. Moreover, cultivation of the P. pastoris strain secreting β-D-galactosidase in a whey permeate supplemented with Arthrobacter sp. 22c L-arabinose isomerase resulted in a 90% yield

  5. The rhizobacterium Arthrobacter agilis produces dimethylhexadecylamine, a compound that inhibits growth of phytopathogenic fungi in vitro.

    Science.gov (United States)

    Velázquez-Becerra, Crisanto; Macías-Rodríguez, Lourdes I; López-Bucio, José; Flores-Cortez, Idolina; Santoyo, Gustavo; Hernández-Soberano, Christian; Valencia-Cantero, Eduardo

    2013-12-01

    Plant diseases caused by fungal pathogens such as Botrytis cinerea and the oomycete Phytophthora cinnamomi affect agricultural production worldwide. Control of these pests can be done by the use of fungicides such as captan, which may have deleterious effects on human health. This study demonstrates that the rhizobacterium Arthrobacter agilis UMCV2 produces volatile organic compounds that inhibit the growth of B. cinerea in vitro. A single compound from the volatile blends, namely dimethylhexadecylamine (DMHDA), could inhibit the growth of both B. cinerea and P. cinnamomi when supplied to the growth medium in low concentrations. DMHDA also inhibited the growth of beneficial fungi Trichoderma virens and Trichoderma atroviride but at much higher concentrations. DMHDA-related aminolipids containing 4, 8, 10, 12, and 14 carbons in the alkyl chain were tested for their inhibitory effect on the growth of the pathogens. The results show that the most active compound from those tested was dimethyldodecylamine. This effect correlates with a decrease in the number of membrane lipids present in the mycelium of the pathogen including eicosanoic acid, (Z)-9-hexadecenoic acid, methyl ester, and (Z)-9-octadecenoic acid, methyl ester. Strawberry leaflets treated with DMHDA were not injured by the compound. These data indicate that DMHDA and related compounds, which can be produced by microorganisms may effectively inhibit the proliferation of certain plant pathogens.

  6. NAA for studying detoxification of Cr and Hg by Arthrobacter globiformis 151B

    International Nuclear Information System (INIS)

    Tsibakhashvili, N.; Mosulishvili, L.; Kirkesali, E.; Murusidze, I.; Frontasyeva, M.V.; Pavlov, S.S.; Zinicovscaia, I.I.

    2010-01-01

    Instrumental neutron activation analysis was used to study accumulation of Hg(II) and Cr(VI) ions in Arthrobacter globiformis 151B, a gram-positive, Cr(VI)-reducer aerobic bacterium isolated from basalt sample taken from the most polluted region in the Republic of Georgia (Kazreti). Experiments were focused on (1) accumulation of Hg(II) in bacterial cells; (2) accumulation of Cr(VI) in A. globiformis 151B in the presence of Hg(II) and (3) effects of Hg(II) and mixture of Cr(VI)-Hg(II) on the elemental composition of bacteria. It was shown that this bacterial strain possesses uptake mechanisms by which mercury toxicity can be reduced in environment and that accumulation of Cr(VI) in A. globiformis 151B is much higher in the presence of Hg(II) ions. Accumulation of Hg(II), similar to the Cr(VI) accumulation, follows well the Lengmuir-Freundlich model. NAA measurements showed increased content of Fe in bacteria under Hg and Cr action, suggesting that Fe-containing biomolecules play a decisive role in detoxifying of heavy metals by A. globiformis 151B. A concentration of 5000 μg/L of Hg(II) was found to be critical for A. globiformis 151B. At this concentration of Hg(II) the concentrations of both essential (Na, Mg, Al, Cl, K, Mn, Zn) and some non-essential elements (Rb, Sb, Sc, As) changed drastically along with a decrease of the biomass of bacteria by a factor of two. One may assume that under this high exposure to Hg(II) the structure of the bacterial cell wall was destroyed. (author)

  7. Characterizing the Catalytic Potential of Deinococcus, Arthrobacter and other Robust Bacteria in Contaminated Subsurface Environments of the Hanford Site

    Energy Technology Data Exchange (ETDEWEB)

    Daly, Michael J.

    2005-06-01

    Natural selection in highly radioactive waste sites may yield bacteria with favorable bioremediating characteristics. However, until recently the microbial ecology of such environments has remained unexplored because of the high costs and technical complexities associated with extracting and characterizing samples from such sites. We have examined the bacterial ecology within radioactive sediments from a high-level nuclear waste plume in the vadose zone on the DOE?s Hanford Site in south-central Washington state (Fredrickson et al, 2004). Manganese-dependent, radiation resistant bacteria have been isolated from this contaminated site including the highly Mn-dependent Deinococcus and Arthrobacter spp.

  8. Statistical optimization of process parameters for inulinase production from Tithonia weed by Arthrobacter mysorens strain no.1.

    Science.gov (United States)

    Kamble, Prajakta P; Kore, Maheshkumar V; Patil, Sushama A; Jadhav, Jyoti P; Attar, Yasmin C

    2018-06-01

    Tithonia rotundifolia is an easily available and abundant inulin rich weed reported to be competitive and allelopathic. This weed inulin is hydrolyzed by inulinase into fructose. Response surface methodology was employed to optimize culture conditions for the inulinase production from Arthrobacter mysorens strain no.1 isolated from rhizospheric area of Tithonia weed. Initially, Plackett- Burman design was used for screening 11 nutritional parameters for inulinase production including inulin containing weeds as cost effective substrate. The experiment shows that amongst the 11 parameters studied, K 2 HPO 4 , Inulin, Agave sisalana extract and Tithonia rotundifolia were the most significant variables for inulinase production. Quantitative effects of these 4 factors were further investigated using Box Behnken design. The medium having 0.27% K 2 HPO 4 , 2.54% Inulin, 6.57% Agave sisalana extract and 7.27% Tithonia rotundifolia extract were found to be optimum for maximum inulinase production. The optimization strategies used showed 2.12 fold increase in inulinase yield (1669.45 EU/ml) compared to non-optimized medium (787 EU/ml). Fructose produced by the action of inulinase was further confirmed by spectrophotometer, osazone, HPTLC and FTIR methods. Thus Tithonia rotundifolia can be used as an eco-friendly, economically feasible and promising alternative substrate for commercial inulinase production yielding fructose from Arthrobacter mysorens strain no.1. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. A miniaturized solid contact test with Arthrobacter globiformis for the assessment of the environmental impact of silver nanoparticles.

    Science.gov (United States)

    Engelke, Maria; Köser, Jan; Hackmann, Stephan; Zhang, Huanjun; Mädler, Lutz; Filser, Juliane

    2014-05-01

    Silver nanoparticles (AgNPs) are widely applied for their antibacterial activity. Their increasing use in consumer products implies that they will find their way into the environment via wastewater-treatment plants. The aim of the present study was to compare the ecotoxicological impact of 2 differently designed AgNPs using the solid contact test for the bacterial strain Arthrobacter globiformis. In addition, a miniaturized version of this test system was established, which requires only small-sized samples because AgNPs are produced in small quantities during the design level. The results demonstrate that the solid contact test can be performed in 24-well microplates and that the miniaturized test system fulfills the validity criterion. Soils spiked with AgNPs showed a concentration-dependent reduction of Arthrobacter dehydrogenase activity for both AgNPs and Ag ions (Ag(+)). The toxic effect of the investigated AgNPs on the bacterial viability differed by 1 order of magnitude and can be related to the release of dissolved Ag(+). The release of dissolved Ag(+) can be attributed to particle size and surface area or to the fact that AgNPs are in either metallic or oxide form. Environ © 2014 SETAC.

  10. New Genome Sequence of an Echinaceapurpurea Endophyte, Arthrobacter sp. Strain EpSL27, Able To Inhibit Human-Opportunistic Pathogens.

    Science.gov (United States)

    Miceli, Elisangela; Presta, Luana; Maggini, Valentina; Fondi, Marco; Bosi, Emanuele; Chiellini, Carolina; Fagorzi, Camilla; Bogani, Patrizia; Di Pilato, Vincenzo; Rossolini, Gian Maria; Mengoni, Alessio; Firenzuoli, Fabio; Perrin, Elena; Fani, Renato

    2017-06-22

    We announce here the draft genome sequence of Arthrobacter sp. strain EpSL27, isolated from the stem and leaves of the medicinal plant Echinacea purpurea and able to inhibit human-pathogenic bacterial strains. The genome sequencing of this strain may lead to the identification of genes involved in the production of antimicrobial molecules. Copyright © 2017 Miceli et al.

  11. Arthrobacter P 1, a Fast Growing Versatile Methylotroph with Amine Oxidase as a Key Enzyme in the Metabolism of Methylated Amines

    NARCIS (Netherlands)

    Dijken, J.P. van; Veenhuis, M.; Harder, W.

    1981-01-01

    A facultative methylotrophic bacterium was isolated from enrichment cultures containing methylamine as the sole carbon source. It was tentatively identified as an Arthrobacter species. Extracts of cells grown on methylamine or ethylamine contained high levels of amine oxidase (E.C. 1.4.3) activity.

  12. Production of β-Fructofuranosidase by Arthrobacter sp. and Its Application in the Modification of Stevioside and Rebaudioside A

    Directory of Open Access Journals (Sweden)

    Zhong-Wei Xu

    2009-01-01

    Full Text Available Arthrobacter sp. 10137 has been used to produce β-fructofuranosidase (FFase. Sucrose and corn steep powder in an optimized ratio of 10:1 were the best carbon and nitrogen sources for enzyme production in a shake flask. The maximum FFase activity was 26.69 U/mL after 22.5 h in batch culture, and the crude FFase, obtained by ultrafiltration and (NH42SO4 fractionation, was purified about 7-fold as measured by specific activity from the crude culture filtrate. The FFase was specific for introduction of a fructose molecule at the C19 position on both the stevioside and rebaudioside A, with high transfructosylating activity of 65 % after 15 h of incubation.

  13. [Bacterium Arthrobacter agilis UMCV2 and diverse amines inhibit in vitro growth of wood-decay fungi].

    Science.gov (United States)

    Orozco-Mosqueda, M Del Carmen; Valencia-Cantero, Eduardo; López-Albarrán, Pablo; Martínez-Pacheco, Mauro; Velázquez-Becerra, Crisanto

    2015-01-01

    The kingdom Fungi is represented by a large number of organisms, including pathogens that deteriorate the main structural components of wood, such as cellulose, hemicellulose and lignin. The aim of our work was to characterize the antifungal activity in Arthrobacter agilis UMCV2 and diverse amines against wood-decaying fungi. Four fungal organisms (designated as UMTM) were isolated from decaying wood samples obtained from a forest in Cuanajo-Michoacán, México. Two of them showed a clear enzymatic activity of cellulases, xylanases and oxido-reducing enzymes and were identified as Hypocrea (UMTM3 isolate) and Fusarium (UMTM13 isolate). In vitro, the amines showed inhibitory effect against UMTM growth and one of the amines, dimethylhexadecylamine (DMA16), exhibited strong potential as wood preventive treatment, against the attack of decaying fungi. Copyright © 2015 Asociación Argentina de Microbiología. Publicado por Elsevier España, S.L.U. All rights reserved.

  14. Characterizing the Catalytic Potential of Deinococcus, Arthrobacter and other Robust Bacteria in Contaminated Subsurface Environments of the Hanford Site

    International Nuclear Information System (INIS)

    Daly, Michael J.

    2006-01-01

    Ionizing Radiation (IR) Resistance in Bacteria. Until recently, there have been no clear physiologic predictors of a cell's ability to recover from ionizing radiation (IR) and other DOE-relevant oxidative stress conditions. In general, the most resistant bacteria have been Gram-positive (e.g., Deinococcus, Arthrobacter, Lactobacillus and Enterococcus spp.) and the most sensitive have been Gram-negative (e.g., Pseudomonas, Shewanella and Neisseria spp.). However, there are several reported exceptions to this paradigm, the Gram-negative cyanobacterium Chroococcidiopsis is extremely resistant to IR, whereas the Gram-positive Micrococcus luteus is sensitive. We have identified biomolecular signatures for radiation sensitivity and resistance which are independent of phylogeny, where very high and very low intracellular Mn/Fe concentration ratios correlated with very high and very low resistances, respectively; and restricting Mn(II) in the famously resistant Deinococcus radiodurans sensitized this eubacterium to IR

  15. Characterizing the Catalytic Potential of Deinococcus, Arthrobacter and other Robust Bacteria in Contaminated Subsurface Environments of the Hanford Site

    International Nuclear Information System (INIS)

    Fredrickson, Jim K.; Daly, Michael J.

    2006-01-01

    Until recently, there have been no clear physiologic predictors of a cell's ability to recover from ionizing radiation (IR), desiccation, and other DOE-relevant oxidative stress conditions. In general, the most resistant bacteria have been Gram-positive (e.g., Deinococcus, Arthrobacter, Lactobacillus and Enterococcus spp.) and the most sensitive have been Gram-negative (e.g., Pseudomonas, Shewanella and Neisseria spp.). However, there are several reported exceptions to this paradigm, the Gram-negative cyanobacterium Chroococcidiopsis is extremely resistant to IR, whereas the Gram-positive Micrococcus luteus is sensitive. We have identified biomolecular signatures for radiation sensitivity and resistance which are independent of phylogeny, where very high and very low intracellular Mn/Fe concentration ratios correlated with very high and very low resistances, respectively; and restricting Mn(II) in the famously resistant Deinococcus radiodurans sensitized this eubacterium to IR (http://cfyn.ifas.ufl.edu/radiation.pdf)

  16. Characterizing the Catalytic Potential of Deinococcus, Arthrobacter and other Robust Bacteria in Contaminated Subsurface Environments of the Hanford Site

    Energy Technology Data Exchange (ETDEWEB)

    Fredrickson, Jim K.; Daly, Michael J.

    2006-06-01

    Until recently, there have been no clear physiologic predictors of a cell's ability to recover from ionizing radiation (IR), desiccation, and other DOE-relevant oxidative stress conditions. In general, the most resistant bacteria have been Gram-positive (e.g., Deinococcus, Arthrobacter, Lactobacillus & Enterococcus spp.) and the most sensitive have been Gram-negative (e.g., Pseudomonas, Shewanella & Neisseria spp.). However, there are several reported exceptions to this paradigm, the Gram-negative cyanobacterium Chroococcidiopsis is extremely resistant to IR, whereas the Gram-positive Micrococcus luteus is sensitive. We have identified biomolecular signatures for radiation sensitivity and resistance which are independent of phylogeny, where very high and very low intracellular Mn/Fe concentration ratios correlated with very high and very low resistances, respectively; and restricting Mn(II) in the famously resistant Deinococcus radiodurans sensitized this eubacterium to IR (http://cfyn.ifas.ufl.edu/radiation.pdf).

  17. Characterizing the Catalytic Potential of Deinococcus, Arthrobacter and other Robust Bacteria in Contaminated Subsurface Environments of the Hanford Site

    Energy Technology Data Exchange (ETDEWEB)

    Daly, Michael J.

    2006-05-01

    Ionizing Radiation (IR) Resistance in Bacteria. Until recently, there have been no clear physiologic predictors of a cell's ability to recover from ionizing radiation (IR) and other DOE-relevant oxidative stress conditions. In general, the most resistant bacteria have been Gram-positive (e.g., Deinococcus, Arthrobacter, Lactobacillus & Enterococcus spp.) and the most sensitive have been Gram-negative (e.g., Pseudomonas, Shewanella & Neisseria spp.). However, there are several reported exceptions to this paradigm, the Gram-negative cyanobacterium Chroococcidiopsis is extremely resistant to IR, whereas the Gram-positive Micrococcus luteus is sensitive. We have identified biomolecular signatures for radiation sensitivity and resistance which are independent of phylogeny, where very high and very low intracellular Mn/Fe concentration ratios correlated with very high and very low resistances, respectively; and restricting Mn(II) in the famously resistant Deinococcus radiodurans sensitized this eubacterium to IR.

  18. Organization of genes responsible for the stereospecific conversion of hydantoins to alpha-amino acids in Arthrobacter aurescens DSM 3747.

    Science.gov (United States)

    Wiese, A; Syldatk, C; Mattes, R; Altenbuchner, J

    2001-09-01

    Arthrobacter aurescens DSM 3747 hydrolyzes stereospecifically 5'-monosubstituted hydantoins to alpha-amino acids. The genes involved in hydantoin utilization (hyu) were isolated on an 8.7-kb DNA fragment, and by DNA sequence analysis eight ORFs were identified. The hyu gene cluster includes four genes: hyuP encoding a putative transport protein, the hydantoin racemase gene hyuA, the hydantoinase gene hyuH, and the carbamoylase gene hyuC. The four genes are transcribed in the same direction. Upstream of hyuP and in opposite orientation to the hyu genes, three ORFs were found showing similarities to cytochrome P450 monooxygenase (ORF1, incomplete), to membrane proteins (ORF2), and to ferredoxin (ORF3). ORF8 was found downstream of hyuC and again in opposite orientation to the hyu genes. The gene product of ORF8 displayed similarities to the LacI/GalR family of transcriptional regulators. Reverse transcriptase PCR experiments and Northern blot analysis revealed that the genes hyuPAHC are coexpressed in A. aurescens after induction with 3-N-CH3-IMH. The expression of the hyu operon was not regulated by the putative regulator ORF8 as shown by gene disruption and mobility-shift experiments.

  19. Sodium alginate-grafted β-cyclodextrins as a matrix for immobilized Arthrobacter simplex for cortisone acetate biotransfromation

    Science.gov (United States)

    Shen, Yanbing; Niu, Lulu; Yu, Ziqi; Wang, Min; Shang, Zhihua; Yang, Yan

    2018-06-01

    Cyclodextrins (CDs) are used to resolve the low aqueous solubility of steroids, but the high cost of CDs is still a limiting factor in biotransformation process. This study, which is based on grafting and immobilization techniques, focused on synthesizing for the first time sodium alginate (SA)-grafted β-CD (SA-β-CD) and alginate-grafted β-CD for the immobilization of Arthrobacter simplex (ASP) cells (SA-β-CD-cells) and subsequent recycling of CDs and cells. FTIR spectium and X-ray diffraction proved that β-CD was successfully grafted with SA, whereas the grafting yield of β-CD was 10.3 μmol g-1. SA-β-CD could increase the solubility of CA by 3.5-fold, whereas the transformation rate was enhanced by 10%. The conversion ratio of CA was over 92% after the SA-β-CD recycling for nine cycles. In addition, after SA-β-CD-cells were applied in biocatalytic reactions for eight cycles, the conversion ratio of CA was over 90%. These advantages suggest great potential for using both grafting and immobilized techniques in steroid transformation.

  20. Evaluation of Arthrobacter aurescens Strain TC1 as Bioaugmentation Bacterium in Soils Contaminated with the Herbicidal Substance Terbuthylazine.

    Directory of Open Access Journals (Sweden)

    Vera P Silva

    Full Text Available In the last years the chloro-s-triazine active substance terbuthylazine has been increasingly used as an herbicide and may leave residues in the environment which can be of concern. The present study aimed at developing a bioaugmentation tool based on the soil bacterium Arthrobacter aurescens strain TC1 for the remediation of terbuthylazine contaminated soils and at examining its efficacy for both soil and aquatic compartments. First, the feasibility of growing the bioaugmentation bacterium inocula on simple sole nitrogen sources (ammonium and nitrate instead of atrazine, while still maintaining its efficiency to biodegrade terbuthylazine was shown. In sequence, the successful and quick (3 days bioremediation efficacy of ammonium-grown A. aurescens TC1 cells was proven in a natural soil freshly spiked or four-months aged with commercial terbuthylazine at a dose 10× higher than the recommended in corn cultivation, to mimic spill situations. Ecotoxicity assessment of the soil eluates towards a freshwater microalga supported the effectiveness of the bioaugmentation tool. Obtained results highlight the potential to decontaminate soil while minimizing terbuthylazine from reaching aquatic compartments via the soil-water pathway. The usefulness of this bioaugmentation tool to provide rapid environment decontamination is particularly relevant in the event of accidental high herbicide contamination. Its limitations and advantages are discussed.

  1. Evaluation of Arthrobacter aurescens Strain TC1 as Bioaugmentation Bacterium in Soils Contaminated with the Herbicidal Substance Terbuthylazine

    Science.gov (United States)

    Silva, Vera P.; Moreira-Santos, Matilde; Mateus, Carla; Teixeira, Tânia; Ribeiro, Rui; Viegas, Cristina A.

    2015-01-01

    In the last years the chloro-s-triazine active substance terbuthylazine has been increasingly used as an herbicide and may leave residues in the environment which can be of concern. The present study aimed at developing a bioaugmentation tool based on the soil bacterium Arthrobacter aurescens strain TC1 for the remediation of terbuthylazine contaminated soils and at examining its efficacy for both soil and aquatic compartments. First, the feasibility of growing the bioaugmentation bacterium inocula on simple sole nitrogen sources (ammonium and nitrate) instead of atrazine, while still maintaining its efficiency to biodegrade terbuthylazine was shown. In sequence, the successful and quick (3 days) bioremediation efficacy of ammonium-grown A. aurescens TC1 cells was proven in a natural soil freshly spiked or four-months aged with commercial terbuthylazine at a dose 10× higher than the recommended in corn cultivation, to mimic spill situations. Ecotoxicity assessment of the soil eluates towards a freshwater microalga supported the effectiveness of the bioaugmentation tool. Obtained results highlight the potential to decontaminate soil while minimizing terbuthylazine from reaching aquatic compartments via the soil-water pathway. The usefulness of this bioaugmentation tool to provide rapid environment decontamination is particularly relevant in the event of accidental high herbicide contamination. Its limitations and advantages are discussed. PMID:26662024

  2. Biodegradation of p-nitrophenol using Arthrobacter chlorophenolicus A6 in a novel upflow packed bed reactor.

    Science.gov (United States)

    Sahoo, Naresh Kumar; Pakshirajan, Kannan; Ghosh, Pranab Kumar

    2011-06-15

    A novel packed bed reactor (PBR) was designed with cross flow aeration at multiple ports along the depth to improve the hydrodynamic conditions of the reactor, and the biodegradation efficiency of Arthrobacter chlorophenolicus A6 on p-nitrophenol (PNP) removal in PBR at different PNP loading rates were evaluated. The novel PBR was designed to improve the hydrodynamic features such as mixing time profile (t(m95)), oxygen mass transfer coefficient (k(L)a), and overall gas hold up capacity (ɛ(G)) of the reactor. PNP concentration in the influent was varied between 600 and 1400 mg l(-1) whereas the hydraulic retention time (HRT) in the reactor was varied between 18 and 7.5h. Complete removal of PNP was achieved in the reactor up to a PNP loading rate of 2787 mg l(-1)d(-1). More than 99.9% removal of PNP was achieved in the reactor for an influent concentration of 1400 mg l(-1) and at 18 h HRT. In the present study, PNP was utilized as sole source of carbon and energy by A. chlorophenolicus A6. Furthermore, the bioreactor showed good compatibility in handling shock loading of PNP. Copyright © 2011 Elsevier B.V. All rights reserved.

  3. Biodegradation of p-nitrophenol using Arthrobacter chlorophenolicus A6 in a novel upflow packed bed reactor

    International Nuclear Information System (INIS)

    Sahoo, Naresh Kumar; Pakshirajan, Kannan; Ghosh, Pranab Kumar

    2011-01-01

    A novel packed bed reactor (PBR) was designed with cross flow aeration at multiple ports along the depth to improve the hydrodynamic conditions of the reactor, and the biodegradation efficiency of Arthrobacter chlorophenolicus A6 on p-nitrophenol (PNP) removal in PBR at different PNP loading rates were evaluated. The novel PBR was designed to improve the hydrodynamic features such as mixing time profile (t m95 ), oxygen mass transfer coefficient (k L a), and overall gas hold up capacity (ε G ) of the reactor. PNP concentration in the influent was varied between 600 and 1400 mg l -1 whereas the hydraulic retention time (HRT) in the reactor was varied between 18 and 7.5 h. Complete removal of PNP was achieved in the reactor up to a PNP loading rate of 2787 mg l -1 d -1 . More than 99.9% removal of PNP was achieved in the reactor for an influent concentration of 1400 mg l -1 and at 18 h HRT. In the present study, PNP was utilized as sole source of carbon and energy by A. chlorophenolicus A6. Furthermore, the bioreactor showed good compatibility in handling shock loading of PNP.

  4. Biodegradation of 4-bromophenol by Arthrobacter chlorophenolicus A6T in a newly designed packed bed reactor.

    Science.gov (United States)

    Sahoo, Naresh Kumar; Ghosh, Pranab Kumar; Pakshirajan, Kannan

    2013-02-01

    Bromophenol is listed as a priority pollutant by the U.S. EPA. However, there has been no report on the removal of bromophenol in any biological system that is operated in a continuous mode. The efficiency of Arthrobacter chlorophenolicus A6(T) on the biodegradation of 4-bromophenol (4-BP) in a newly designed packed bed reactor (PBR) was evaluated with different influent 4-BP concentrations between 400 mg l(-1) and 1200 mg l(-1) and hydraulic retention times (HRTs) between 24 h and 7.5 h. The response of the PBR to 4-BP shock loadings was also tested, and the bioreactor was found to adequately handle these shock loadings. The percentage of effluent toxicity in the PBR was tested using mixed microbial consortia as the test species; this experiment was performed using a 4-BP influent concentration of 1200 mg l(-1) and HRTs between 24 h and 7.5 h. A maximal 98% effluent toxicity removal was achieved when the PBR was operated at an HRT of 24 h. In the present study, 4-BP was used as the sole source of carbon and energy, and the complete removal of 4-BP was achieved with 4-BP loading rates of up to 2277 mg l(-1) day(-1). Copyright © 2012 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  5. Evidence for cooperative mineralization of diuron by Arthrobacter sp. BS2 and Achromobacter sp. SP1 isolated from a mixed culture enriched from diuron exposed environments.

    Science.gov (United States)

    Devers-Lamrani, Marion; Pesce, Stéphane; Rouard, Nadine; Martin-Laurent, Fabrice

    2014-12-01

    Diuron was found to be mineralized in buffer strip soil (BS) and in the sediments (SED) of the Morcille river in the Beaujolais vineyard repeatedly treated with this herbicide. Enrichment cultures from BS and SED samples led to the isolation of three bacterial strains transforming diuron to 3,4-dichloroaniline (3,4-DCA) its aniline derivative. 16S rRNA sequencing revealed that they belonged to the genus Arthrobacter (99% of similarity to Arthrobacter globiformis strain K01-01) and were designated as Arthrobacter sp. BS1, BS2 and SED1. Diuron-degrading potential characterized by sequencing of the puhA gene, characterizing the diuron-degradaing potential, revealed 99% similarity to A. globiformis strain D47 puhA gene isolated a decade ago in the UK. These isolates were also able to use chlorotoluron for their growth. Although able to degrade linuron and monolinuron to related aniline derivatives they were not growing on them. Enrichment cultures led to the isolation of a strain from the sediments entirely degrading 3,4-DCA. 16S rRNA sequence analysis showed that it was affiliated to the genus Achromobacter (99% of similarity to Achromobacter sp. CH1) and was designated as Achromobacter sp. SP1. The dcaQ gene encoding enzyme responsible for the transformation of 3,4-DCA to chlorocatechol was found in SP1 with 99% similarity to that of Comamonas testosteroni WDL7. This isolate also used for its growth a range of anilines (3-chloro-4-methyl-aniline, 4-isopropylaniline, 4-chloroaniline, 3-chloroaniline, 4-bromoaniline). The mixed culture composed of BS2 and SP1 strains entirely mineralizes (14)C-diuron to (14)CO2. Diuron-mineralization observed in the enrichment culture could result from the metabolic cooperation between these two populations. Copyright © 2014. Published by Elsevier Ltd.

  6. Induction of a M/sub r/ 21,000 polypeptide in an Arthrobacter Sp. by dye-sensitized photooxidation

    International Nuclear Information System (INIS)

    Franzi, J.J.

    1985-01-01

    Irradiation of aerobic cultures of an Arthrobacter species with near-UV light and oxygen induced synthesis of a cell surface protein, M/sub r/ 21,000 polypeptide. Visible light, oxygen and a sensitizing dye were also effective in induction. Far-UV light, bleomycin and nalidixic acid, all inducers of the recA protein in Escherichia coli, were ineffective inducers of this protein. Furthermore, X-irradiation and radical-generating oxidants failed to induce synthesis of the M/sub r/ 21,000 polypeptide. DNA binding dyes proved to be capable of inducing synthesis of this protein or inhibiting dye-mediated stimulation of synthesis of this protein. For example, dGdC-specific dyes (e.g. methylene blue, neutral red, acridine orange or ethidium bromide) were efficient inducers of the M/sub r/ 21,000 polypeptide. Also methylene blue and neutral red were more efficient inducers than were acridine orange or ethidium bromide, which could be explained by the greater dGdC specificity and, possibly by the greater photoreactivity of methylene blue and neutral red. dAdT-specific dyes such as methyl green or daunomycin effectively inhibited dye-mediated induction. Rose bengal is an anionic dye which does not bind to DNA but does mediate the photooxidation of deoxyguanosine residues in DNA. It is an efficient inducer of the M/sub r/ 21,000 polypeptide. Induction with this dye is nearly eliminated when novobiocin, an inhibitor of DNA gyrase (topoisomerase II) which mediates relaxation, is added in conjunction with rose bengal

  7. Induction of a M/sub r/ 21,000 polypeptide in an Arthrobacter Sp. by dye-sensitized photooxidation

    Energy Technology Data Exchange (ETDEWEB)

    Franzi, J.J.

    1985-01-01

    Irradiation of aerobic cultures of an Arthrobacter species with near-UV light and oxygen induced synthesis of a cell surface protein, M/sub r/ 21,000 polypeptide. Visible light, oxygen and a sensitizing dye were also effective in induction. Far-UV light, bleomycin and nalidixic acid, all inducers of the recA protein in Escherichia coli, were ineffective inducers of this protein. Furthermore, X-irradiation and radical-generating oxidants failed to induce synthesis of the M/sub r/ 21,000 polypeptide. DNA binding dyes proved to be capable of inducing synthesis of this protein or inhibiting dye-mediated stimulation of synthesis of this protein. For example, dGdC-specific dyes (e.g. methylene blue, neutral red, acridine orange or ethidium bromide) were efficient inducers of the M/sub r/ 21,000 polypeptide. Also methylene blue and neutral red were more efficient inducers than were acridine orange or ethidium bromide, which could be explained by the greater dGdC specificity and, possibly by the greater photoreactivity of methylene blue and neutral red. dAdT-specific dyes such as methyl green or daunomycin effectively inhibited dye-mediated induction. Rose bengal is an anionic dye which does not bind to DNA but does mediate the photooxidation of deoxyguanosine residues in DNA. It is an efficient inducer of the M/sub r/ 21,000 polypeptide. Induction with this dye is nearly eliminated when novobiocin, an inhibitor of DNA gyrase (topoisomerase II) which mediates relaxation, is added in conjunction with rose bengal.

  8. Enhanced U(VI) release from autunite mineral by aerobic Arthrobacter sp. in the presence of aqueous bicarbonate

    Energy Technology Data Exchange (ETDEWEB)

    Katsenovich, Yelena; Carvajal, Denny A.; Wellman, Dawn M.; Lagos, Leonel

    2012-04-20

    The bacterial effect on U(VI) leaching from the autunite mineral (Ca[(UO{sub 2})(PO{sub 4})]{sub 2} {center_dot} 3H{sub 2}O) was investigated to provide a more comprehensive understanding into important microbiological processes affecting autunite stability within subsurface bicarbonate-bearing environments. Experiments were performed in a culture of G975 Arthrobacter oxydans strain, herein referred to as G975, a soil bacterium previously isolated from Hanford Site soil. 91 mg of autunite powder and 50 mL of phosphorus-limiting sterile media were amended with bicarbonate ranging between 1-10 mM in glass reactor bottles and inoculated with G975 strain after the dissolution of autunite was at steady state. SEM observations indicated G975 formed a biofilm on the autunite surface and penetrated the mineral cleavages. The mineral surface colonization by bacteria tended to increase concomitantly with bicarbonate concentrations. Additionally, a sterile cultureware with inserts was used in non-contact bioleaching experiments where autunite and bacteria cells were kept separately. The data suggest the G975 bacteria is able to enhance U(VI) leaching from autunite without the direct contact with the mineral. In the presence of bicarbonate, the damage to bacterial cells caused by U(VI) toxicity was reduced, yielding similar values for total organic carbon (TOC) degradation and cell density compared to U(VI)-free controls. The presence of active bacterial cells greatly enhanced the U(VI) bioleaching from autunite in bicarbonate-amended media.

  9. Enhanced U(VI) release from autunite mineral by aerobic Arthrobacter sp. in the presence of aqueous bicarbonate

    Energy Technology Data Exchange (ETDEWEB)

    Katsenovich, Yelena P.; Carvajal, Denny A.; Wellman, Dawn M.; Lagos, Leonel E.

    2012-05-01

    The bacterial effect on U(VI) release from the autunite mineral (Ca[(UO2)(PO4)]2•3H2O) was investigated to provide a more comprehensive understanding of the important microbiological processes affecting autunite stability within subsurface bicarbonate-bearing environments. Experiments were performed in a culture of the Arthrobacter oxydans G975 strain, herein referred to as G975, a soil bacterium previously isolated from Hanford Site soil. 91 mg of autunite powder and 50 mL of phosphorous-limiting sterile media were amended with bicarbonate (ranging between 1 and 10 mM) in glass reactor bottles and inoculated with the G975 strain after the dissolution of autunite was at steady state. SEM observations indicated that G975 formed a biofilm on the autunite surface and penetrated the mineral cleavages. The mineral surface colonization by bacteria tended to increase concomitantly with bicarbonate concentrations. Additionally, a sterile culture-ware with inserts was used in non-contact dissolution experiments where autunite and bacteria cells were kept separately. The data suggest that G975 bacteria is able to enhance the release of U(VI) from autunite without direct contact with the mineral. In the presence of bicarbonate, the damage to bacterial cells caused by U(VI) toxicity was reduced, yielding similar values for total organic carbon (TOC) degradation and cell density compared to U(VI)-free controls. The presence of active bacterial cells greatly enhanced the release of U(VI) from autunite in bicarbonate-amended media.

  10. Complete genome sequence of Arthrobacter alpinus ERGS4:06, a yellow pigmented bacterium tolerant to cold and radiations isolated from Sikkim Himalaya.

    Science.gov (United States)

    Kumar, Rakshak; Singh, Dharam; Swarnkar, Mohit Kumar; Singh, Anil Kumar; Kumar, Sanjay

    2016-02-20

    Arthrobacter alpinus ERGS4:06, a yellow pigmented bacterium which exhibited tolerance to cold and UV radiations was isolated from the glacial stream of East Rathong glacier in Sikkim Himalaya. Here we report the 4.3Mb complete genome assembly that has provided the basis for potential role of pigments as a survival strategy to combat stressed environment of cold and high UV-radiation and additionally the ability to produce cold active industrial enzymes. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Key enzymes enabling the growth of Arthrobacter sp. strain JBH1 with nitroglycerin as the sole source of carbon and nitrogen.

    Science.gov (United States)

    Husserl, Johana; Hughes, Joseph B; Spain, Jim C

    2012-05-01

    Flavoprotein reductases that catalyze the transformation of nitroglycerin (NG) to dinitro- or mononitroglycerols enable bacteria containing such enzymes to use NG as the nitrogen source. The inability to use the resulting mononitroglycerols limits most strains to incomplete denitration of NG. Recently, Arthrobacter strain JBH1 was isolated for the ability to grow on NG as the sole source of carbon and nitrogen, but the enzymes and mechanisms involved were not established. Here, the enzymes that enable the Arthrobacter strain to incorporate NG into a productive pathway were identified. Enzyme assays indicated that the transformation of nitroglycerin to mononitroglycerol is NADPH dependent and that the subsequent transformation of mononitroglycerol is ATP dependent. Cloning and heterologous expression revealed that a flavoprotein catalyzes selective denitration of NG to 1-mononitroglycerol (1-MNG) and that 1-MNG is transformed to 1-nitro-3-phosphoglycerol by a glycerol kinase homolog. Phosphorylation of the nitroester intermediate enables the subsequent denitration of 1-MNG in a productive pathway that supports the growth of the isolate and mineralization of NG.

  12. Identification of a recombinant inulin fructotransferase (difructose dianhydride III forming) from Arthrobacter sp. 161MFSha2.1 with high specific activity and remarkable thermostability.

    Science.gov (United States)

    Wang, Xiao; Yu, Shuhuai; Zhang, Tao; Jiang, Bo; Mu, Wanmeng

    2015-04-08

    Difructose dianhydride III (DFA III) is a functional carbohydrate produced from inulin by inulin fructotransferase (IFTase, EC 4.2.2.18). In this work, an IFTase gene from Arthrobacter sp. 161MFSha2.1 was cloned and expressed in Escherachia coli. The recombinant enzyme was purified by metal affinity chromatography. It showed significant inulin hydrolysis activity, and the produced main product from inulin was determined as DFA III by nuclear magnetic resonance analysis. The molecular mass of the purified protein was calculated to be 43 and 125 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and gel filtration, respectively, suggesting the native enzyme might be a homotrimer. The recombinant enzyme showed maximal activity as 2391 units/mg at pH 6.5 and 55 °C. It displayed the highest thermostability among previously reported IFTases (DFA III forming) and was stable up to 80 °C for 4 h of incubation. The smallest substrate was determined as nystose. The conversion ratio of inulin to DFA III reached 81% when 100 g/L inulin was catalyzed by 80 nM recombinant enzyme for 20 min at pH 6.5 and 55 °C. All of these data indicated that the IFTase (DFA III forming) from Arthrobacter sp. 161MFSha2.1 had great potential for industrial DFA III production.

  13. Low temperature reduction of hexavalent chromium by a microbial enrichment consortium and a novel strain of Arthrobacter aurescens

    Directory of Open Access Journals (Sweden)

    Thompson Vicki S

    2006-01-01

    Full Text Available Abstract Background Chromium is a transition metal most commonly found in the environment in its trivalent [Cr(III] and hexavalent [Cr(VI] forms. The EPA maximum total chromium contaminant level for drinking water is 0.1 mg/l (0.1 ppm. Many water sources, especially underground sources, are at low temperatures (less than or equal to 15 Centigrade year round. It is important to evaluate the possibility of microbial remediation of Cr(VI contamination using microorganisms adapted to these low temperatures (psychrophiles. Results Core samples obtained from a Cr(VI contaminated aquifer at the Hanford facility in Washington were enriched in Vogel Bonner medium at 10 Centigrade with 0, 25, 50, 100, 200, 400 and 1000 mg/l Cr(VI. The extent of Cr(VI reduction was evaluated using the diphenyl carbazide assay. Resistance to Cr(VI up to and including 1000 mg/l Cr(VI was observed in the consortium experiments. Reduction was slow or not observed at and above 100 mg/l Cr(VI using the enrichment consortium. Average time to complete reduction of Cr(VI in the 30 and 60 mg/l Cr(VI cultures of the consortium was 8 and 17 days, respectively at 10 Centigrade. Lyophilized consortium cells did not demonstrate adsorption of Cr(VI over a 24 hour period. Successful isolation of a Cr(VI reducing organism (designated P4 from the consortium was confirmed by 16S rDNA amplification and sequencing. Average time to complete reduction of Cr(VI at 10 Centigrade in the 25 and 50 mg/l Cr(VI cultures of the isolate P4 was 3 and 5 days, respectively. The 16S rDNA sequence from isolate P4 identified this organism as a strain of Arthrobacter aurescens, a species that has not previously been shown to be capable of low temperature Cr(VI reduction. Conclusion A. aurescens, indigenous to the subsurface, has the potential to be a predominant metal reducer in enhanced, in situ subsurface bioremediation efforts involving Cr(VI and possibly other heavy metals and radionuclides.

  14. Recombinant Arthrobacter β-1, 3-glucanase as a potential effector molecule for paratransgenic control of Chagas disease.

    Science.gov (United States)

    Jose, Christo; Klein, Nicole; Wyss, Sarah; Fieck, Annabeth; Hurwitz, Ivy; Durvasula, Ravi

    2013-03-14

    Chagas disease is most often transmitted to humans by Trypanosoma cruzi infected triatomine bugs, and remains a significant cause of morbidity and mortality in Central and South America. Control of Chagas disease has relied mainly on vector eradication. However, development of insect resistance has prompted us to develop a paratransgenic strategy to control vectorial transmission of T. cruzi. Here, the potential role of recombinant endoglucanases as anti-trypanosomal agents for paratransgenic application is examined. The surface of T. cruzi is covered by a thick coat of mucin-like glycoproteins that have been proposed to play a role in the binding of T. cruzi to the membrane surface of the vector gut. We hypothesize that disruption of these glycoconjugates could arrest parasite development in the vector and abort the transmission cycle. In this work, we examine the effects of recombinant Arthrobacter luteus β-1, 3-glucanase expressed via Rhodococcus rhodnii on T. cruzi Sylvio II strain. The coding sequence for β-1, 3-glucanase was cloned in-frame to a heterologous promoter/signal sequence from the Mycobacterium kansasii alpha antigen gene resident in an E. coli/R. rhodnii shuttle vector. The resulting construct was confirmed by sequencing, and electroporated into R. rhodnii. Expression products from positive clones were purified from log phase cultures followed by dialysis into physiological buffers. Lysates and media were quantitated by ELISA against rabbit antibody specific to β-1,3-glucanase. Glucanase-positive samples were applied to live T. cruzi parasites in culture and viability accessed by spectrophotometric and fluorescent microscopic measurements. R. rhodnii-expressed β-1,3-glucanase exhibited toxicity against T. cruzi compared to controls when applied at 5 and 10% of the total culture volume. The decrease in cell viability ranged from a maximum of 50% for the media treatments to 80% for the filtered lysates. These results suggest that recombinant

  15. PLASMID-ENCODED PHTHALATE CATABOLIC PATHWAY IN ARTHROBACTER KEYSERI 12B: BIOTRANSFORMATIONS OF 2-SUBSTITUTED BENZOATES AND THEIR USE IN CLONING AND CHARACTERIZATION OF PHTHALATE CATABOLISM GENES AND GENE PRODUCTS

    Science.gov (United States)

    Several 2-substituted benzoates (including 2-trifluoromethyl-, 2-chloro-, 2-bromo-, 2-iodo-, 2-nitro-, 2-methoxy-, and 2-acetyl-benzoates) were converted by phthalate-grown Arthrobacter keyseri 12B to the corresponding 2-substituted 3,4-dihydroxybenzoates (protocatechuates)...

  16. Monitoring Arthrobacter protophormiae RKJ100 in a 'tag and chase' method during p-nitrophenol bio-remediation in soil microcosms.

    Science.gov (United States)

    Pandey, Gunjan; Pandey, Janmejay; Jain, Rakesh K

    2006-05-01

    Monitoring of micro-organisms released deliberately into the environment is essential to assess their movement during the bio-remediation process. During the last few years, DNA-based genetic methods have emerged as the preferred method for such monitoring; however, their use is restricted in cases where organisms used for bio-remediation are not well characterized or where the public domain databases do not provide sufficient information regarding their sequence. For monitoring of such micro-organisms, alternate approaches have to be undertaken. In this study, we have specifically monitored a p-nitrophenol (PNP)-degrading organism, Arthrobacter protophormiae RKJ100, using molecular methods during PNP degradation in soil microcosm. Cells were tagged with a transposon-based foreign DNA sequence prior to their introduction into PNP-contaminated microcosms. Later, this artificially introduced DNA sequence was PCR-amplified to distinguish the bio-augmented organism from the indigenous microflora during PNP bio-remediation.

  17. Statistical optimization of beta-carotene production by Arthrobacter agilis A17 using response surface methodology and Box-Behnken design

    Science.gov (United States)

    Özdal, Murat; Özdal, Özlem Gür; Gürkök, Sümeyra

    2017-04-01

    β-carotene is a commercially important natural pigment and has been widely applied in the medicine, pharmaceutical, food, feed and cosmetic industries. The current study aimed to investigate the usability of molasses for β-carotene production by Arthrobacter agilis A17 (KP318146) and to optimize the production process. Box-Behnken Design of Response Surface Methodology was used to determine the optimum levels and the interactions of three independent variables namely molasses, yeast extract and KH2PO4 at three different levels. β-carotene yield in optimized medium containing 70 g/l molasses, 25 g/l yeast extract and 0.96 g/l KH2PO4, reached up to 100 mg/l, which is approximately 2.5-fold higher than the yield, obtained from control cultivation. A remarkable β-carotene production on inexpensive carbon source was achieved with the use of statistical optimization.

  18. A new cold-adapted β-D-galactosidase from the Antarctic Arthrobacter sp. 32c – gene cloning, overexpression, purification and properties

    Directory of Open Access Journals (Sweden)

    Kur Józef

    2009-07-01

    Full Text Available Abstract Background The development of a new cold-active β-D-galactosidases and microorganisms that efficiently ferment lactose is of high biotechnological interest, particularly for lactose removal in milk and dairy products at low temperatures and for cheese whey bioremediation processes with simultaneous bio-ethanol production. Results In this article, we present a new β-D-galactosidase as a candidate to be applied in the above mentioned biotechnological processes. The gene encoding this β-D-galactosidase has been isolated from the genomic DNA library of Antarctic bacterium Arthrobacter sp. 32c, sequenced, cloned, expressed in Escherichia coli and Pichia pastoris, purified and characterized. 27 mg of β-D-galactosidase was purified from 1 L of culture with the use of an intracellular E. coli expression system. The protein was also produced extracellularly by P. pastoris in high amounts giving approximately 137 mg and 97 mg of purified enzyme from 1 L of P. pastoris culture for the AOX1 and a constitutive system, respectively. The enzyme was purified to electrophoretic homogeneity by using either one step- or a fast two step- procedure including protein precipitation and affinity chromatography. The enzyme was found to be active as a homotrimeric protein consisting of 695 amino acid residues in each monomer. Although, the maximum activity of the enzyme was determined at pH 6.5 and 50°C, 60% of the maximum activity of the enzyme was determined at 25°C and 15% of the maximum activity was detected at 0°C. Conclusion The properties of Arthrobacter sp. 32cβ-D-galactosidase suggest that this enzyme could be useful for low-cost, industrial conversion of lactose into galactose and glucose in milk products and could be an interesting alternative for the production of ethanol from lactose-based feedstock.

  19. Similarities in the induction of synthesis of a cell-surface polypeptide in Arthrobacter sp. by near-UV irradiation and photodynamic conditions

    International Nuclear Information System (INIS)

    Hoober, J.K.; Franzi, J.

    1983-01-01

    Irradiation of aerobic suspensions of Arthrobacter sp. with near-UV light (310-400 nm) induced synthesis of a 21 000 dalton, cell-surface polypeptide. Synthesis of this polypeptide also was induced by visible light in the presence of photodynamic dyes. Induction of the polypeptide in ear-UV light and with visible light plus dyes was inhibited by histidine. Hemin inhibited induction in near-UV light and in visible light with methylene blue, neutral red and acriflavin, which are cationic dyes, but failed to inhibit induction in visible light with rose bengal, an anionic dye. These results suggested that inhibition by hemin required electrostatically favored interaction between the anionic porphyrin and the sensitizer, and that the near-UV light effect was mediated by a cationic or neutral endogenous sensitizer. The similarities in the responses of the cells to near-UV irradiation and visible light plus dyes suggested that the mechanism of induction under the two conditions was the same. (author)

  20. Biodegradation of 4-bromophenol by Arthrobacter chlorophenolicus A6 in batch shake flasks and in a continuously operated packed bed reactor.

    Science.gov (United States)

    Sahoo, Naresh Kumar; Pakshirajan, Kannan; Ghosh, Pranab Kumar

    2014-04-01

    The present study investigated growth and biodegradation of 4-bromophenol (4-BP) by Arthrobacter chlorophenolicus A6 in batch shake flasks as well as in a continuously operated packed bed reactor (PBR). Batch growth kinetics of A. chlorophenolicus A6 in presence of 4-BP followed substrate inhibition kinetics with the estimated biokinetic parameters value of μ max = 0.246 h(-1), K i = 111 mg L(-1), K s  = 30.77 mg L(-1) and K = 100 mg L(-1). In addition, variations in the observed and theoretical biomass yield coefficient and maintenance energy of the culture were investigated at different initial 4-BP concentration. Results indicates that the toxicity tolerance and the biomass yield of A. chlorophenolicus A6 towards 4-BP was found to be poor as the organism utilized the substrate mainly for its metabolic maintenance energy. Further, 4-BP biodegradation performance by the microorganism was evaluated in a continuously operated PBR by varying the influent concentration and hydraulic retention time in the ranges 400-1,200 mg L(-1) and 24-7.5 h, respectively. Complete removal of 4-BP was achieved in the PBR up to a loading rate of 2,276 mg L(-1) day(-1).

  1. Toxicity screening of soils from different mine areas—A contribution to track the sensitivity and variability of Arthrobacter globiformis assay

    Energy Technology Data Exchange (ETDEWEB)

    Marques, Catarina R., E-mail: crmarques@ua.pt [Departamento de Biologia and CESAM (Centro de Estudos do Ambiente e do Mar), Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro (Portugal); Caetano, Ana L. [Departamento de Biologia and CESAM (Centro de Estudos do Ambiente e do Mar), Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro (Portugal); Haller, Andreas [ECT Oekotoxikologie GmbH, Böttgerstraße 2–14, D-65439 Flörsheim a. M. (Germany); Gonçalves, Fernando [Departamento de Biologia and CESAM (Centro de Estudos do Ambiente e do Mar), Universidade de Aveiro, Campus Universitário de Santiago, 3810-193 Aveiro (Portugal); Pereira, Ruth [Faculdade de Ciências da Universidade do Porto, Rua do Campo Alegre, s/n, 4169-007 Porto (Portugal); Interdisciplinary Centre of Marine and Environmental Research (CIIMAR/CIMAR), Universidade do Porto, Rua dos Bragas 289, P 4050-123 Porto (Portugal); Römbke, Jörg [ECT Oekotoxikologie GmbH, Böttgerstraße 2–14, D-65439 Flörsheim a. M. (Germany)

    2014-06-01

    Highlights: • The assay gave rapid and feasible discrimination of toxic soils to A. globiformis. • Sensitive and low variability response to soils from different regions. • Soil properties may interfere with metal toxicity and fluorescence measurements. • Proposal of a toxicity threshold for the contact assay regarding soils. • A. globiformis assay should be included in the Tier I of risk assessment frameworks. - Abstract: This study used the Arthrobacter globiformis solid-contact test for assessing the quality of soils collected in areas subjected to past and present mine activities in Europe (uranium mine, Portugal) and North Africa (phosphogypsum pile, Tunisia; iron mine, Morocco). As to discriminate the influence of soils natural variability from the effect of contaminants, toxicity thresholds were derived for this test, based on the dataset of each study area. Furthermore, the test sensitivity and variability was also evaluated. As a result, soils that inhibited A. globiformis dehydrogenase activity above 45% or 50% relatively to the control, were considered to be toxic. Despite the soil metal content determined, the properties of soils seemed to influence dehydrogenase activity. Overall, the contact test provided a coherent outcome comparing to other more time-consuming and effort-demanding ecotoxicological assays. Our results strengthened the feasibility and ecological relevance of this assay, which variability was quite reduced hence suggesting its potential integration within the test battery of tier 1 of soil risk assessment schemes.

  2. Toxicity screening of soils from different mine areas—A contribution to track the sensitivity and variability of Arthrobacter globiformis assay

    International Nuclear Information System (INIS)

    Marques, Catarina R.; Caetano, Ana L.; Haller, Andreas; Gonçalves, Fernando; Pereira, Ruth; Römbke, Jörg

    2014-01-01

    Highlights: • The assay gave rapid and feasible discrimination of toxic soils to A. globiformis. • Sensitive and low variability response to soils from different regions. • Soil properties may interfere with metal toxicity and fluorescence measurements. • Proposal of a toxicity threshold for the contact assay regarding soils. • A. globiformis assay should be included in the Tier I of risk assessment frameworks. - Abstract: This study used the Arthrobacter globiformis solid-contact test for assessing the quality of soils collected in areas subjected to past and present mine activities in Europe (uranium mine, Portugal) and North Africa (phosphogypsum pile, Tunisia; iron mine, Morocco). As to discriminate the influence of soils natural variability from the effect of contaminants, toxicity thresholds were derived for this test, based on the dataset of each study area. Furthermore, the test sensitivity and variability was also evaluated. As a result, soils that inhibited A. globiformis dehydrogenase activity above 45% or 50% relatively to the control, were considered to be toxic. Despite the soil metal content determined, the properties of soils seemed to influence dehydrogenase activity. Overall, the contact test provided a coherent outcome comparing to other more time-consuming and effort-demanding ecotoxicological assays. Our results strengthened the feasibility and ecological relevance of this assay, which variability was quite reduced hence suggesting its potential integration within the test battery of tier 1 of soil risk assessment schemes

  3. Physiological and Comparative Genomic Analysis of Arthrobacter sp. SRS-W-1-2016 Provides Insights on Niche Adaptation for Survival in Uraniferous Soils

    Directory of Open Access Journals (Sweden)

    Ashvini Chauhan

    2018-01-01

    Full Text Available Arthrobacter sp. strain SRS-W-1-2016 was isolated on high concentrations of uranium (U from the Savannah River Site (SRS that remains co-contaminated by radionuclides, heavy metals, and organics. SRS is located on the northeast bank of the Savannah River (South Carolina, USA, which is a U.S. Department of Energy (DOE managed ecosystem left historically contaminated from decades of nuclear weapons production activities. Predominant contaminants within the impacted SRS environment include U and Nickel (Ni, both of which can be transformed microbially into less toxic forms via metal complexation mechanisms. Strain SRS-W-1-2016 was isolated from the uraniferous SRS soils on high concentrations of U (4200 μM and Ni (8500 μM, but rapid growth was observed at much lower concentrations of 500 μM U and 1000 μM Ni, respectively. Microcosm studies established with strain SRS-W-1-2016 revealed a rapid decline in the concentration of spiked U such that it was almost undetectable in the supernatant by 72 h of incubation. Conversely, Ni concentrations remained unchanged, suggesting that the strain removed U but not Ni under the tested conditions. To obtain a deeper understanding of the metabolic potential, a draft genome sequence of strain SRS-W-1-2016 was obtained at a coverage of 90×, assembling into 93 contigs with an N50 contig length of 92,788 bases. The genomic size of strain SRS-W-1-2016 was found to be 4,564,701 bases with a total number of 4327 putative genes. An in-depth, genome-wide comparison between strain SRS-W-1-2016 and its four closest taxonomic relatives revealed 1159 distinct genes, representing 26.7% of its total genome; many associating with metal resistance proteins (e.g., for cadmium, cobalt, and zinc, transporter proteins, stress proteins, cytochromes, and drug resistance functions. Additionally, several gene homologues coding for resistance to metals were identified in the strain, such as outer membrane efflux pump proteins

  4. Physiological and Comparative Genomic Analysis of Arthrobacter sp. SRS-W-1-2016 Provides Insights on Niche Adaptation for Survival in Uraniferous Soils.

    Science.gov (United States)

    Chauhan, Ashvini; Pathak, Ashish; Jaswal, Rajneesh; Edwards, Bobby; Chappell, Demario; Ball, Christopher; Garcia-Sillas, Reyna; Stothard, Paul; Seaman, John

    2018-01-11

    Arthrobacter sp. strain SRS-W-1-2016 was isolated on high concentrations of uranium (U) from the Savannah River Site (SRS) that remains co-contaminated by radionuclides, heavy metals, and organics. SRS is located on the northeast bank of the Savannah River (South Carolina, USA), which is a U.S. Department of Energy (DOE) managed ecosystem left historically contaminated from decades of nuclear weapons production activities. Predominant contaminants within the impacted SRS environment include U and Nickel (Ni), both of which can be transformed microbially into less toxic forms via metal complexation mechanisms. Strain SRS-W-1-2016 was isolated from the uraniferous SRS soils on high concentrations of U (4200 μM) and Ni (8500 μM), but rapid growth was observed at much lower concentrations of 500 μM U and 1000 μM Ni, respectively. Microcosm studies established with strain SRS-W-1-2016 revealed a rapid decline in the concentration of spiked U such that it was almost undetectable in the supernatant by 72 h of incubation. Conversely, Ni concentrations remained unchanged, suggesting that the strain removed U but not Ni under the tested conditions. To obtain a deeper understanding of the metabolic potential, a draft genome sequence of strain SRS-W-1-2016 was obtained at a coverage of 90×, assembling into 93 contigs with an N50 contig length of 92,788 bases. The genomic size of strain SRS-W-1-2016 was found to be 4,564,701 bases with a total number of 4327 putative genes. An in-depth, genome-wide comparison between strain SRS-W-1-2016 and its four closest taxonomic relatives revealed 1159 distinct genes, representing 26.7% of its total genome; many associating with metal resistance proteins (e.g., for cadmium, cobalt, and zinc), transporter proteins, stress proteins, cytochromes, and drug resistance functions. Additionally, several gene homologues coding for resistance to metals were identified in the strain, such as outer membrane efflux pump proteins, peptide

  5. Investigation of the biosynthesis of acetyl-CoA and oxaloacetic acid from pyruvic acid and the quantitative evaluation of incorporated 13C-labeled l-alanine in Arthrobacter hyalinus

    International Nuclear Information System (INIS)

    Katsumi Iida

    2014-01-01

    Studies on the contribution to acetyl-CoA and oxaloacetic acid from the pyruvic acid transformation from l-alanine in Arthrobacter hyalinus were conducted by means of feeding experiments with l-[1- 13 C]alanine and l-[3- 13 C]alanine, followed by an analysis of the labeling patterns of coproporphyrinogen III using 13 C NMR spectroscopy. The results demonstrated that l-alanine was transformed via pyruvic acid to both acetyl-CoA and oxaloacetic acid. Additionally, the quantitative analysis indicated that pyruvic acid was transformed to acetyl-CoA and oxaloacetic acid in the ratio of 1:0.8. (author)

  6. Cyanide as a copper and quinone-directed inhibitor of amine oxidases from pea seedlings ( Pisum sativum) and Arthrobacter globiformis: evidence for both copper coordination and cyanohydrin derivatization of the quinone cofactor.

    Science.gov (United States)

    Shepard, Eric M; Juda, Gregory A; Ling, Ke-Qing; Sayre, Lawrence M; Dooley, David M

    2004-04-01

    The interactions of cyanide with two copper-containing amine oxidases (CuAOs) from pea seedlings (PSAO) and the soil bacterium Arthrobacter globiformis (AGAO) have been investigated by spectroscopic and kinetic techniques. Previously, we rationalized the effects of azide and cyanide for several CuAOs in terms of copper coordination by these exogenous ligands and their effects on the internal redox equilibrium TPQ(amr)-Cu(II) right harpoon over left harpoon TPQ(sq)-Cu(I). The mechanism of cyanide inhibition was proposed to occur through complexation to Cu(I), thereby directly competing with O(2) for reoxidation of TPQ. Although cyanide readily and reversibly reacts with quinones, no direct spectroscopic evidence for cyanohydrin derivatization of TPQ has been previously documented for CuAOs. This work describes the first direct spectroscopic evidence, using both model and enzyme systems, for cyanohydrin derivatization of TPQ. K(d) values for Cu(II)-CN(-) and Cu(I)-CN(-), as well as the K(i) for cyanide inhibition versus substrate amine, are reported for PSAO and AGAO. In spite of cyanohydrin derivatization of the TPQ cofactor in these enzymes, the uncompetitive inhibition of amine oxidation is determined to arise almost exclusively through CN(-) complexation of Cu(I).

  7. Porphyrin formation and its regulation in Arthrobacter

    NARCIS (Netherlands)

    Kortstee, G.J.J.

    1969-01-01

    Porphyrins (tetrapyrroles) are the basic compounds of a number of substances functioning in living organisms as carriers of oxygen (hemoglobin), carriers of electrons (cytochromes) or as a trap for radiant energy (chlorophyll). In these active forms the tetrapyrroles contain a metal and are

  8. Quantitative evaluation of the biosynthetic pathways leading to δ-aminolevulinic acid from the Shemin precursor glycine via the C5 pathway in Arthrobacter hyalinus by analysis of 13C-labeled coproporphyrinogen III biosynthesized from [2-13C]glycine, [1-13C]acetate, and [2-13C]acetate using 13C NMR spectroscopy

    International Nuclear Information System (INIS)

    Katsumi Iida

    2013-01-01

    The biosynthetic pathways leading to δ-aminolevulinic acid (ALA) from the Shemin precursor glycine via the C5 pathway in Arthrobacter hyalinus were quantitatively evaluated by means of feeding experiments with [2- 13 C]glycine, sodium [1- 13 C]acetate, and sodium [2- 13 C]acetate, followed by analysis of the labeling patterns of coproporphyrinogen III (Copro'gen III) (biosynthesized from ALA) using 13 C NMR spectroscopy. Two biosynthetic pathways leading to ALA from glycine via the C5 pathway were identified: i.e., transformation of glycine to l-serine catalyzed by glycine hydroxymethyltransferase, and glycine synthase-catalyzed catabolism of glycine to N 5 , N 10 -methylene-tetrahydrofolic acid (THF), which reacts with another molecule of glycine to afford l-serine. l-Serine is transformed to acetyl-CoA via pyruvic acid. Acetyl-CoA enters the tricarboxylic acid cycle, affording 2-oxoglutaric acid, which in turn is transformed to l-glutamic acid. The l-glutamic acid enters the C5 pathway, affording ALA in A. hyalinus. A 13 C NMR spectroscopic comparison of the labeling patterns of Copro'gen III obtained after feeding of [2- 13 C]glycine, sodium [1- 13 C]acetate, and sodium [2- 13 C]acetate showed that [2- 13 C]glycine transformation and [2- 13 C]glycine catabolism in A. hyalinus proceed in the ratio of 52 and 48 %. The reaction of [2- 13 C]glycine and N 5 , N 10 -methylene-THF, that of glycine and N 5 , N 10 -[methylene- 13 C]methylene-THF generated from the [2- 13 C]glycine catabolism, and that of [2- 13 C]glycine and N 5 , N 10 -[methylene- 13 C]methylene-THF transformed the fed [2- 13 C]glycine to [1- 13 C]acetyl-CoA, [2- 13 C]acetyl-CoA, and [1,2- 13 C 2 ]acetyl-CoA in the ratios of 42, 37, and 21 %, respectively. These labeled acetyl-CoAs were then incorporated into ALA. Our results provide a quantitative picture of the pathways of biosynthetic transformation to ALA from glycine in A. hyalinus. (author)

  9. Pigments produced by the bacteria belonging to the genus Arthrobacter

    OpenAIRE

    Sutthiwong , Nuthathai; Caro , Yanis; Fouillaud , Mireille; Laurent , Philippe; Valla , A.; Dufossé , Laurent

    2013-01-01

    Poster communication, 7th International Congress of Pigments in Food – New technologies towards health, through colors, Novara, Italy, June 18-21, 2013.; International audience; Since several decades, pigments have been used as a taxonomic tool for the identification and classification of bacteria. Nowadays, pigment producing microorganisms have been also widely interested in scientific disciplines because of their biotechnological potential. With the growing interest in microbial pigments be...

  10. Arthrobacter enclensis sp. nov., isolated from sediment sample

    Digital Repository Service at National Institute of Oceanography (India)

    Dastager, S.G.; Qin, L.; Tang, S.K.; Krishnamurthi, S.; Lee, J.C.; Li, W.J.

    A novel bacterial strain designated as NIO-1008(T) was isolated from marine sediments sample in Chorao Island India. Cells of the strains were gram positive and non-motile, displayed a rod-coccus life cycle and formed cream to light grey colonies...

  11. Metabolic regulation in the facultative methylotroph arthrobacter P1

    NARCIS (Netherlands)

    1985-01-01

    Many microorganisms are able to utilize C1 compounds, i.e. compounds which do not contain carbon-carbon bonds, as carbon- and energy sources for growth. In order to synthesize cell constituents from these C1 compounds special metabolic pathways are employed by such organisms. Although a great deal

  12. Degradation of 4-fluorophenol by Arthrobacter sp strain IF1

    NARCIS (Netherlands)

    Ferreira, Maria Isabel M.; Marchesi, Julian R.; Janssen, Dick B.

    A Gram-positive bacterial strain capable of aerobic biodegradation of 4-fluorophenol (4-FP) as the sole source of carbon and energy was isolated by selective enrichment from soil samples collected near an industrial site. The organism, designated strain IF1, was identified as a member of the genus

  13. Screening of degradative plasmids from Arthrobacter sp. HW08 and ...

    African Journals Online (AJOL)

    Administrator

    2011-06-08

    Jun 8, 2011 ... Media were solidified, if necessary, by the addition of 15 g agar ... genome extraction reagent kit, plasmid DNA fast extraction kit and. DNA segments ... spectrophotometer (Spectronic Instruments, Rochester, NY) and. SW content .... cultivation on LB slant for 100 times at 30 °C for 2 days, it was found that ...

  14. Autochthonous bioaugmentation with environmental samples rich in hydrocarbonoclastic bacteria for bench-scale bioremediation of oily seawater and desert soil.

    Science.gov (United States)

    Ali, Nedaa; Dashti, Narjes; Salamah, Samar; Al-Awadhi, Husain; Sorkhoh, Naser; Radwan, Samir

    2016-05-01

    Oil-contaminated seawater and desert soil batches were bioaugmented with suspensions of pea (Pisum sativum) rhizosphere and soil with long history of oil pollution. Oil consumption was measured by gas-liquid chromatography. Hydrocarbonoclastic bacteria in the bioremediation batches were counted using a mineral medium with oil vapor as a sole carbon source and characterized by their 16S ribosomal RNA (rRNA)-gene sequences. Most of the oil was consumed during the first 2-4 months, and the oil-removal rate decreased or ceased thereafter due to nutrient and oxygen depletion. Supplying the batches with NaNO3 (nitrogen fertilization) at a late phase of bioremediation resulted in reenhanced oil consumption and bacterial growth. In the seawater batches bioaugmented with rhizospheric suspension, the autochthonous rhizospheric bacterial species Microbacterium oxidans and Rhodococcus spp. were established and contributed to oil-removal. The rhizosphere-bioaugmented soil batches selectively favored Arthrobacter nitroguajacolicus, Caulobacter segnis, and Ensifer adherens. In seawater batches bioaugmented with long-contaminated soil, the predominant oil-removing bacterium was the marine species Marinobacter hydrocarbonoclasticus. In soil batches on the other hand, the autochthonous inhabitants of the long-contaminated soil, Pseudomonas and Massilia species were established and contributed to oil removal. It was concluded that the use of rhizospheric bacteria for inoculating seawater and desert soil and of bacteria in long-contaminated soil for inoculating desert soil follows the concept of "autochthonous bioaugmentation." Inoculating seawater with bacteria in long-contaminated soil, on the other hand, merits the designation "allochthonous bioaugmentation."

  15. Effect of Arthrobacter agilis UMCV2 on germination and growth of Pinus devoniana Lindley

    Directory of Open Access Journals (Sweden)

    Wilber Montejo-Mayo

    2016-03-01

    Full Text Available Soil microorganisms are essential for growth, emergence and development in all plants. In our study we decided to evaluate the effect that A. agilis UMCV2 rhizobacteria had on germination and growth of plants of economic-forest interest as P. devoniana to an age of 65 days. Our results show that the UMCV2 bacteria promoted growth of P. devoniana at this early stage of development, further highlighting that despite the short time of interaction between these two, the bacterium was able to increase the rate of germination, increase the size of shoot and generate a proliferation of lateral roots. The data shows a huge potential for using inoculum both in the greenhouse and in open ground and generate a growth promoting species of interest in both agricultural and forest, thereby reducing production periods depending on the crop.

  16. Application of thermoalkalophilic xylanase from Arthrobacter sp. MTCC 5214 in biobleaching of kraft pulp

    Digital Repository Service at National Institute of Oceanography (India)

    Khandeparker, R.; Bhosle, N.B.

    released by enzyme treatment showed a characteristic peak at 280 nm indicating the presence of lignin in the released coloring matter. Enzymatic prebleaching of kraft pulp showed 20 % reduction in kappa number of the pulp without much change in viscosity...

  17. Purification and characterization of alpha-L-arabinofuranosidase from Arthrobacter sp. MTCC 5214 in solid-state fermentation

    Digital Repository Service at National Institute of Oceanography (India)

    Khandeparker, R.; Numan, M.T.H.; Mukherjee, B.; Satwekar, A.; Bhosle, N.B.

    M p-nitrophenyl-a-L- arabinofuranoside(pNPAF),50 mMglycine–NaOHbuffer,pH8 andanappropriately dilutedenzymesolution.Afterincubatingthereactionmixtureat80 8Cfor10 min,the reaction was stopped by adding ice-cold 1 M Na 2 CO 3 (1 ml) and the liberated p...., USA) column as above. The active fractions were pooled and used for further studies. 2.9. Kinetic determinations Initial reaction rates of pNPAF hydrolysis were determined using different substrate concentrations (0.08–6.8 mM) of pNPAF in 50 mM glycine...

  18. Characterizing the Catalytic Potential of Deinococcus, Arthrobacter and other Robust Bacteria in Contaminated Subsurface Environments of the Hanford Site

    Energy Technology Data Exchange (ETDEWEB)

    Daly, Michael J.

    2007-07-23

    Progress is briefly summarized in these areas: ionizing radiation resistance in bacteria; a hypothesis regarding ionizing radiation resistance emerging for bacterial cells; transcriptome analysis of irradiated D. radiodurans and Shewanella oneidensis; the role of metal reduction in Mn-dependnet Deinococcal species; and engineered Deinococcus strains as models for bioremediation. Key findings are also reported regarding protein oxidation as a possible key to bacterial desiccation resistance, and the whole-genome sequence of the thermophile Deinococcus geothermalis.

  19. Isolation, purification and characterization of xylanase produced by Arthrobacter sp. MTCC 5214 when grown in solid-state fermentation

    Digital Repository Service at National Institute of Oceanography (India)

    Khandeparker, R.; Bhosle, N.B.

    %) fractionation, and purified to homogeneity using size exclusion and ion exchange chromatography. The molecular mass of xylanase was approx. 20 kDa. Enzyme retained 100% activity at pH 7 and 8 for 24 h. It was interesting to note that at higher pH such as 9, 10...

  20. MOLECULAR GENE CLONING OF NICOTINE-DEHIDROGENASE FROM THE pAO1 MEGAPLASMID OF ARTHROBACTER NICOTINOVORANS

    Directory of Open Access Journals (Sweden)

    Andreea Andrei

    2013-10-01

    Full Text Available 6-hydroxi-L-nicotine (6HNic has an important potential as a drug for neuro-degenerative disorders and a  suitable simple and reliable method for obtaining contaminant-free 6HNic preparations is required. Here, we envision the in-vitro production of 6HNic by using purified nicotine-dehydrogenase (NDH followed by HPLC or capillary electrophoresis techniques and we focus on the isolation and cloning of the three genes coding the NDH enzyme.  A PCR protocol was established for easy amplification and the DNA fragment containing the ndhLSM genes was directionally cloned into the pART2 vector.

  1. Optimization of culturing conditions for isolated Arthrobacter sp. ZXY-2, an effective atrazine-degrading and salt-adaptive bacterium

    NARCIS (Netherlands)

    Zhao, X.; Wang, Li; Du, Linna; Yang, Jixian; Dong, Jing; Ma, Fang

    2017-01-01

    The increasing salinity in aquatic environments has had a negative impact on the biodegradation of atrazine, an extensively used herbicide which has been proven to pollute soil and water ecosystems. In the present study, a novel atrazine-degrading strain (ZXY-2) was isolated from industrial

  2. Class 1 integrons and tetracycline resistance genes in Alcaligenes, Arthrobacter, and Pseudomonas spp. isolated from pigsties and manured soil

    DEFF Research Database (Denmark)

    Agersø, Yvonne; Sandvang, Dorthe

    2005-01-01

    The presence of tetracycline resistance (Tc-r) genes and class I integrons (in-1), and their ability to cotransfer were investigated in Tc-r gram-negative (185 strains) and gram-positive (72 strains) bacteria from Danish farmland and pigsties. The isolates belonged to the groups or species...... tet(33). No isolates contained more than one tet gene. The in-l-positive isolates were tested for resistance to selected antimicrobial agents and showed resistance to three to nine drugs. Filter-mating experiments showed cotransfer of Tc-r and class I integrons from soil isolates to Escherichia coli...... and/or Pseudomonas putida. We conclude that soil bacteria in close contact to manure or pigsty environment may thus have an important role in horizontal spread of resistance. Use of tetracyclines in food animal production may increase not only Tc-r but also multidrug resistance (caused by the presence...

  3. Formulation and stabilization of an Arthrobacter strain with good storage stability and 4-chlorophenol-degradation activity for bioremediation

    NARCIS (Netherlands)

    Bjerketorp, Joakim; Röling, Wilfred F.M.; Feng, Xin Mei; Garcia, Armando Hernández; Heipieper, Hermann J.; Håkansson, Sebastian

    Chlorophenols are widespread and of environmental concern due to their toxic and carcinogenic properties. Development of less costly and less technically challenging remediation methods are needed; therefore, we developed a formulation based on micronized vermiculite that, when air-dried, resulted

  4. NCBI nr-aa BLAST: CBRC-MLUC-01-0100 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-MLUC-01-0100 ref|YP_002487505.1| translation initiation factor IF-2 [Arthrobacter chlorophenolic... translation initiation factor IF-2 [Arthrobacter chlorophenolicus A6] YP_002487505.1 3e-04 28% ...

  5. NCBI nr-aa BLAST: CBRC-LAFR-01-0212 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-LAFR-01-0212 ref|YP_833238.1| hypothetical protein Arth_3763 [Arthrobacter sp.... FB24] gb|ABK05138.1| hypothetical protein Arth_3763 [Arthrobacter sp. FB24] YP_833238.1 0.48 31% ...

  6. NCBI nr-aa BLAST: CBRC-RMAC-14-0300 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-RMAC-14-0300 ref|YP_832933.1| hypothetical protein Arth_3458 [Arthrobacter sp.... FB24] gb|ABK04833.1| hypothetical protein Arth_3458 [Arthrobacter sp. FB24] YP_832933.1 0.38 24% ...

  7. Application of some microorganisms for synthesis of gold and silver nanoparticles

    International Nuclear Information System (INIS)

    Frontas'eva, M.V.; Pavlov, S.S.; Zinicovscaia, I.I.; Kirkesali, E.I.; Kalabegishvili, T.; Murusidze, I.; Faanhof, A.

    2012-01-01

    In recent years, much attention has been paid to microbial technologies of nanoparticle production. Novel strains of actinomycetes Streptomyces glaucus 71 MD, Streptomyces spp. 211A, arthrobacter genera - Arthrobacter globiformis 151B and Arthrobacter oxydans 61B and blue-green microalga Spirulina platensis were used for synthesis of silver and gold nanoparticles. The studies were carried out using scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDAX), transmission electron microscopy (TEM), X-ray diffraction (XRD), atomic absorption spectrometry (AAS), and neutron activation analysis (NAA)

  8. Reconfirmation of antimicrobial activity in the coelomic fluid of the ...

    Indian Academy of Sciences (India)

    Unknown

    723. Keywords. Antimicrobial activity; column chromatography; earthworm; Eisenia fetida andrei; Tetrazolium salt ... fair resistance against E. coli, P. aeruginosa and Arthrobacter sp., respectively. [Pan W, Liu X, Ge F ... 2.2 Test bacteria species.

  9. Growth of hydrocarbon utilizing microorganisms

    Digital Repository Service at National Institute of Oceanography (India)

    Bhosle, N.B.; Mavinkurve, S.

    Two isolates from marine mud having broad spectrum hydrocarbon utilizing profile were identified as Arthrobacter simplex and Candida tropicalis.Both the organisms grew exponentially on crude oil. The cell yield of the organisms was influenced...

  10. Aerobic Denitrification as an Innovative Method for In-Situ Biological Remediation of Contaminated Subsurface Sites

    Science.gov (United States)

    1989-01-01

    roseus Bacillus stearothermophilus Micrococcus varians Paracoccus denitrificans Bacillus coagulans Paracoccus halodenitrificans Bacillus flrmus Bacillus ...Geodermatophilus Plesiomonas Arachnia Haemophilus Propionibacterium Arthrobacter Halobacteriua Proteus Bacillus Ifalocuccus Pseudoraonas Bacteroides...Mycobacterium peregrinum Nocardia opaca Chromobacterium violaceum Bacillus subtllis Nocardia atlantica Bacillus licheniformis Flavobacterium

  11. Bacteriology of ferromanganese nodules from the Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Chandramohan, D.; LokaBharathi, P.A.; Nair, S.; Matondkar, S.G.P.

    , Micrococcus, Staphylococcus, Arthrobacter@@, and coryneforms were encountered in the present study. Most of the isolates were able to grow on a wide range of sodium chloride concentrations (0 to 10%).The isolates elaborated a number of hydrolytic enzymes...

  12. Bacteriological studies on dairy waste activated sludge

    NARCIS (Netherlands)

    Adamse, A.D.

    1966-01-01

    Dairy-waste activated sludge was examined for bacterial composition and response to different conditions. Strains isolated were classified mainly into three groups: predominantly coryneform bacteria (largely Arthrobacter), some Achromobacteraceae and a small groups of Pseudomonadaceae.

  13. Assessment of active bacteria metabolizing phenolic acids in the peanut (Arachis hypogaea L.) rhizosphere.

    Science.gov (United States)

    Liu, Jinguang; Wang, Xingxiang; Zhang, Taolin; Li, Xiaogang

    2017-12-01

    Phenolic acids can enhance the mycotoxin production and activities of hydrolytic enzymes related to pathogenicity of soilborne fungus Fusarium oxysporum. However, characteristics of phenolic acid-degrading bacteria have not been investigated. The objectives of this study were to isolate and characterize bacteria capable of growth on benzoic and vanillic acids as the sole carbon source in the peanut rhizosphere. Twenty-four bacteria were isolated, and the identification based on 16S rRNA gene sequencing revealed that pre-exposure to phenolic acids before sowing shifted the dominant culturable bacterial degraders from Arthrobacter to Burkholderia stabilis-like isolates. Both Arthrobacter and B. stabilis-like isolates catalysed the aromatic ring cleavage via the ortho pathway, and Arthrobacter isolates did not exhibit higher C12O enzyme activity than B. stabilis-like isolates. The culture filtrate of Fusarium sp. ACCC36194 caused a strong inhibition of Arthrobacter growth but not B. stabilis-like isolates. Additionally, Arthrobacter isolates responded differently to the culture filtrates of B. stabilis-like isolates. The Arthrobacter isolates produced higher indole acetic acid (IAA) levels than B. stabilis-like isolates, but B. stabilis-like isolates were also able to produce siderophores, solubilize mineral phosphate, and exert an antagonistic activity against peanut root rot pathogen Fusarium sp. ACCC36194. Results indicate that phenolic acids can shift their dominant culturable bacterial degraders from Arthrobacter to Burkholderia species in the peanut rhizosphere, and microbial interactions might lead to the reduction of culturable Arthrobacter. Furthermore, increasing bacterial populations metabolizing phenolic acids in monoculture fields might be a control strategy for soilborne diseases caused by Fusarium spp. Copyright © 2017 Elsevier GmbH. All rights reserved.

  14. 块根块茎类作物内生固氮菌分离鉴定、系统发育与促生特性%Isolation, Identification, Phylogeny and Growth Promoting Characteristics of Endophytic Diazotrophs from Tuber and Root Crops

    Institute of Scientific and Technical Information of China (English)

    李艳星; 郭平毅; 孙建光

    2017-01-01

    [Objective]The objectives of this study are to isolate, identify and analyze phylogenetics of endophytic diazotrophs from tuber and root crops, test plant growth promoting (PGP) characteristics of the isolates, and to explore population property and host distributions of endophytic diazotrophs from tuber and root crops. [Method] Surface sterilization and low nitrogen medium were used to isolate endophytic diazotrophs. nifH detection based on PCR amplification to confirm isolates as nitrogen-fixing bacteria. 16S rRNA was amplified with PCR, blasted in EzTaxon after sequencing, and analyzed with Clustalx-MEGA to make phylogenetic tree. PGP characteristics were evaluated by testing 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase activity, indole acetic acid (IAA) production and antagonism to Fusarium spp. [Result] Total 219 endophytic bacterial isolates were obtained from 14 tuber and root samples including radish, carrot, potato, ginger, beet, lotus, yam, taro, cabbage, and sweet potato. All isolates were verified as nitrogen-fixing bacteria after nifH inspection and identified as 79 species of 24 genera based on 16S rRNA. The 79 species are Acinetobacter harbinensis, Arthrobacter arilaitensis, Ar. bergerei, Ar. nicotianae, Ar. nicotinovorans, Ar. nitroguajacolicus, Bacillus amyloliquefaciens, Ba. aryabhattai, Ba. circulans, Ba. fengqiuensis, Ba. firmus, Ba. flexus, Ba. halosaccharovorans, Ba. idriensis, Ba. licheniformis, Ba. litoralis, Ba. luciferensis, Ba. marisflavi, Ba. megaterium, Ba. methylotrophicus, Ba. oceanisediminis, Ba. safensis, Ba. simplex, Ba. sonorensis, Ba. stratosphericus, Ba. subterraneus, Ba. tequilensis, Ba. thaonhiensis, Ba. thioparans, Brevibacillus brevis, Br. formosus, Br. nitrificans, Br. frigoritolerans, Chryseobacterium indoltheticum, Ch. lactis, Citrobacter youngae, Delftia lacustris, Domibacillus indicus, Enterobacter asburiae, E. ludwigii, E. mori, E. xiangfangensis, Fictibacillus barbaricus, Fi. enclensis, Fi. nanhaiensis, Fi

  15. Competitive biosorption of thorium and uranium by Micrococcus luteus

    International Nuclear Information System (INIS)

    Nakajima, A.; Tsuruta, T.

    2004-01-01

    Eighteen species of bacteria were screened for abilities to adsorb thorium and uranium. High adsorption capacity was observed for thorium by Arthrobacter nicotianae and Micrococcus luteus, and for uranium by Arthrobacter nicotianae. The adsorption of both thorium and uranium by Micrococcus luteus cells was rapid, was affected by the solution pH, and obeyed the Langmuir adsorption isotherm for binary systems in a competitive manner taking the ionic charge of the metal ion into account. The thorium selectivity in the competitive adsorption is assumed to be caused by the faster adsorption and the slower desorption rates of thorium than those of uranium. (author)

  16. Acaricomes phytoseiuli gen. nov., sp. nov., isolated from the predatory mite Phytoseiulus persimilis.

    Science.gov (United States)

    Pukall, Rüdiger; Schumann, Peter; Schütte, Conny; Gols, Rieta; Dicke, Marcel

    2006-02-01

    A Gram-positive, rod-shaped, non-spore-forming bacterium, strain CSCT, was isolated from diseased, surface-sterilized specimens of the predatory mite Phytoseiulus persimilis Athias-Henriot and subjected to polyphasic taxonomic analysis. Comparative analysis of the 16S rRNA gene sequence revealed that the strain was a new member of the family Micrococcaceae. Nearest phylogenetic neighbours were determined as Renibacterium salmoninarum (94.0%), Arthrobacter globiformis (94.8%) and Arthrobacter russicus (94.6%). Although the predominant fatty acids (anteiso C15:0), cell-wall sugars (galactose, glucose) and polar lipids (diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol) are in accordance with those of members of the genus Arthrobacter, strain CSCT can be distinguished from members of the genus Arthrobacter by biochemical tests, the absence of a rod-coccus life cycle and the occurrence of the partially saturated menaquinone MK-10(H2) as the predominant menaquinone. The DNA G+C content is 57.7 mol%. On the basis of morphological, chemotaxonomic and phylogenetic differences from other species of the Micrococcaceae, a novel genus and species are proposed, Acaricomes phytoseiuli gen. nov., sp. nov. The type strain is CSCT (=DSM 14247T=CCUG 49701T).

  17. Studies on the occurrence and distribution of heavy metals in ...

    African Journals Online (AJOL)

    The bacteria isolated and identified were. Bacillus subtilis, Bacillus licheniformis, Arthrobacter sp and Achromobacter sp. Fungi isolated were Saccharomyces cerevisiae, Candida utilissima and Sporobolomyces sp. The values for heavy metals for all zones are of public health significance and pose a threat to the survival of ...

  18. Oil and Hydrocarbon Spill Bioremediation Product and Application Technology

    Science.gov (United States)

    1993-05-01

    sludge’ Alkanes PsoudomonasPA rthroba eter, A cineeofbacter, yeasts, Penicillium sp ., Cunninghamells blakesleearia, Absidiaglauca, Mucor spif n-Alkanes...Kiebsiella Heiminthosporium Lactobacillus Mucor Leucothrix Oidiadendrumn Moraxella Paecylomyces Nocardia Phialophora Peptococcus Penicillium Pseudomonas...oleovor:nsab 5 ~Beiyerinckias p., Cunnbnghamellsaleegansim IPseudomonas/Alcaligenss sp . A ci otobacter sp ., Arthrobacter sp ,(k 3Aromatics Pseudomonas

  19. Effects of dispersants on microbial growth and biodegradation of crude oils

    Digital Repository Service at National Institute of Oceanography (India)

    Bhosle, N.B.; Mavinkurve, S.

    Four oil spill dispersants when used along (0.1% V/V) or in combination with Saudi Arabian Crude (0.5% V/V) were non-toxic to Arthrobacter simplex and Candida tropicalis. At a higher concentration of 0.6% (V/V) only D2 was found to be toxic to both...

  20. FMNH2-dependent monooxygenases initiate catabolism of sulfonamides in Microbacterium sp strain BR1 subsisting on sulfonamide antibiotics

    Czech Academy of Sciences Publication Activity Database

    Ricken, B.; Kolvenbach, B.A.; Bergesch, C.; Benndorf, D.; Kroll, K.; Strnad, Hynek; Vlček, Čestmír; Adaixo, R.; Hammes, F.; Shahgaldian, P.; Schaeffer, A.; Kohler, H.P.E.; Corvini, P.F.X.

    2017-01-01

    Roč. 7, podzim (2017), č. článku 15783. ISSN 2045-2322 Institutional support: RVO:68378050 Keywords : resistance mechanism * clinical specimens * sulfamethoxazole * bacteria * degradation * benzylpenicillin * biodegradation * genes * sulfadiazine * arthrobacter Subject RIV: EB - Genetics ; Molecular Biology OBOR OECD: Microbiology Impact factor: 4.259, year: 2016

  1. Long-term nitrogen fertilization decreased the abundance of inorganic phosphate solubilizing bacteria in an alkaline soil

    DEFF Research Database (Denmark)

    Zheng, Bang-Xiao; Hao, Xiuli; Ding, Kai

    2017-01-01

    to Arthrobacter, Bacillus, Brevibacterium and Streptomyces. Long-term P fertilization had no significant effect on the abundance of iPSB communities. Rather than P and potassium (K) additions, long-term nitrogen (N) fertilization decreased the iPSB abundance, which was validated by reduced relative abundance...

  2. The effect of uranium on bacterial viability and cell surface morphology using atomic force microscopy in the presence of bicarbonate ions

    Energy Technology Data Exchange (ETDEWEB)

    Sepulveda-Medina, Paola; Katsenovich, Yelena; Musaramthota, Vishal; Lee, Michelle; Lee, Brady; Dua, Rupak; Lagos, Leonel

    2015-06-01

    Nuclear production facilities during the Cold War have caused liquid waste to leak and soak into the ground creating multiple radionuclide plumes. The Arthrobacter bacteria are one of the most common groups in soils and are found in large numbers in subsurface environments contaminated with radionuclides. This study experimentally analyzed changes on the bacteria surface after uranium exposure and evaluated the effect of bicarbonate ions on U(VI) toxicity of a less uranium tolerant Arthrobacter strain, G968, by investigating changes in adhesion forces and cells dimensions via atomic force microscopy (AFM). AFM and viability studies showed that samples containing bicarbonate are able to acclimate and withstand uranium toxicity. Samples containing no bicarbonate exhibited deformed surfaces and a low height profile, which might be an indication that the cells are not alive.

  3. Evaluating the biological activity of oil-polluted soils using a complex index

    Science.gov (United States)

    Kabirov, R. R.; Kireeva, N. A.; Kabirov, T. R.; Dubovik, I. Ye.; Yakupova, A. B.; Safiullina, L. M.

    2012-02-01

    A complex index characterizing the biological activity of soils (BAS) is suggested. It is based on an estimate of the level of activity of catalase; the number of heterotrophic and hydrocarbon oxidizing microorganisms, microscopic fungi, algae, and cyanobacteria; and the degree of development of higher plants and insects in the studied soil. The data on using the BAS coefficient for evaluating the efficiency of rehabilitation measures for oil-polluted soils are given. Such measures included introducing the following biological preparations: Lenoil based on a natural consortium of microorganisms Bacillus brevis and Arthrobacter sp.; the Azolen biofertilizer with complex action based on Azotobacter vinelandii; the Belvitamil biopreparation, which is the active silt of pulp and paper production; and a ready-mixed industrial association of aerobic and anaerobic microorganisms that contains hydrocarbon oxidizing microorganisms of the Arthrobacter, Bacillus, Candida, Desulfovibrio, and Pseudomonas genera.

  4. Microbiological activities in a shallow-ground repository with cementitious wasteform

    International Nuclear Information System (INIS)

    Varlakova, G.A.; Dyakonova, A.T.; Netrusov, A.I.; Ojovan, M.I.

    2012-01-01

    Cementitious wasteform with immobilised nuclear power plant operational radioactive waste disposed in a near surface testing repository for about 20 years have been analysed for microbiological activities. Clean cultures were selected from the main metabolic groups expected within repository environment e.g. anaerobic de-nitrifying, fermenting, sulphur-reducing, iron-reducing, and oxidizing, thio-bacterium and mushrooms. Microbiological species were identified within cementitious wasteform, in the clayey soil near the wasteform and in the contacting water. The most populated medium was the soil with microbial populations Bacillus, Pseudomonas and Micrococcus, and densities of populations up to 3.6*10 5 colony/g. Microbial populations of generic type Bacillus, Pseudomonas, Rhodococcus, Alcaligenes, Micrococcus, Mycobacterium, and Arthrobacter were identified within cementitious wasteform. Populations of Arthrobacter, Pseudomonas, Alcaligenes, Rhodococcus, Bacillus and Flavobacterium were identified in the water samples contacting the cementitious wasteform. Microbiological species identified are potential destructors of cementitious wasteform and containers. (authors)

  5. Non-Specific Reactions during Immunomagnetic Separation of Listeria

    Directory of Open Access Journals (Sweden)

    Iveta Zachová

    2005-01-01

    Full Text Available Problems occurring during the immunomagnetic separation (IMS of Listeria using immunomagnetic particles Dynabeads® anti-Listeria (Dynal Biotech, Norway were specified. Characteristics of these particles were compared with anti-Listeria spp. magnetite particles (Quantum Magnetics, USA. Pure cultures of Listeria innocua, Arthrobacter spp., Bacillus subtilis, Citrobacter braakii, Escherichia coli, Enterobacter aerogenes, Enterobacter cloacae and Staphylococcus aureus were used to evaluate non-specific reactions during IMS. Gram-positive microorganisms, especially Staphylococcus aureus and Arthrobacter spp., were found to be responsible for non-specific reactions in most cases. The capacity of Dynabeads® anti-Listeria particles was determined to be about 10 % of the initial pure cultures of Listeria spp., after 10 min of incubation. Non-specific reactions during IMS of Listeria were examined on the artificially inoculated food samples in which Gram-positive bacteria showed the highest percentage of capture. Influence of washing in two buffers was also studied.

  6. Radioresistant microorganisms and food irradiation

    Energy Technology Data Exchange (ETDEWEB)

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

    1976-01-01

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

  7. Characterization of the intestinal microbiota of wild-caught and farmed fine flounder (Paralichthys adspersus)

    OpenAIRE

    Salas-Leiva, Joan; Opazo, Rafael; Remond, Camille; Uribe, Eduardo; Velez, Antonio; Romero, Jaime

    2017-01-01

    A comparative analysis of the cultivable intestinal microbiota of farmed (AF) and wild-caught (WF) Paralichthys adspersus was performed. The 16S rRNA gene was used for taxa identification, and the ITS region for strain differentiation. We detected the presence of Vibrio, Bacillus, Photobacterium, Staphylococcus and Carnobacterium in AF, and Exiguobacterium, Klebsiella, Arthrobacter, Raoultella, Kluyvera, Myroides, Streptococcus, Vagococcus, Staphylococcus, Acinetobacter, Psychrobacter, Lactob...

  8. High-density polyethylene (HDPE)-degrading potential bacteria from marine ecosystem of Gulf of Mannar, India.

    Science.gov (United States)

    Balasubramanian, V; Natarajan, K; Hemambika, B; Ramesh, N; Sumathi, C S; Kottaimuthu, R; Rajesh Kannan, V

    2010-08-01

    Assessment of high-density polyethylene (HDPE)-degrading bacteria isolated from plastic waste dumpsites of Gulf of Mannar. Rationally, 15 bacteria (GMB1-GMB15) were isolated by enrichment technique. GMB5 and GMB7 were selected for further studies based on their efficiency to degrade the HDPE and identified as Arthrobacter sp. and Pseudomonas sp., respectively. Assessed weight loss of HDPE after 30 days of incubation was nearly 12% for Arthrobacter sp. and 15% for Pseudomonas sp. The bacterial adhesion to hydrocarbon (BATH) assay showed that the cell surface hydrophobicity of Pseudomonas sp. was higher than Arthrobacter sp. Both fluorescein diacetate hydrolysis and protein content of the biofilm were used to test the viability and protein density of the biomass. Acute peak elevation was observed between 2 and 5 days of inoculation for both bacteria. Fourier transform infrared (FT-IR) spectrum showed that keto carbonyl bond index (KCBI), Ester carbonyl bond index (ECBI) and Vinyl bond index (VBI) were increased indicating changes in functional group(s) and/or side chain modification confirming the biodegradation. The results pose us to suggest that both Pseudomonas sp. and Arthrobacter sp. were proven efficient to degrade HDPE, albeit the former was more efficacious, yet the ability of latter cannot be neglected. Recent alarm on ecological threats to marine system is dumping plastic waste in the marine ecosystem and coastal arena by anthropogenic activity. In maintenance phase of the plastic-derived polyethylene waste, the microbial degradation plays a major role; the information accomplished in this work will be the initiating point for the degradation of polyethylene by indigenous bacterial population in the marine ecosystem and provides a novel eco-friendly solution in eco-management.

  9. Native Michigan plants stimulate soil microbial species changes and PAH remediation at a legacy steel mill.

    Science.gov (United States)

    Thomas, John C; Cable, Edward; Dabkowski, Robert T; Gargala, Stephanie; McCall, Daniel; Pangrazzi, Garett; Pierson, Adam; Ripper, Mark; Russell, Donald K; Rugh, Clayton L

    2013-01-01

    A 1.3-acre phytoremediation site was constructed to mitigate polyaromatic hydrocarbon (PAH) contamination from a former steel mill in Michigan. Soil was amended with 10% (v/v) compost and 5% (v/v) poultry litter. The site was divided into twelve 11.89 m X 27.13 m plots, planted with approximately 35,000 native Michigan perennials, and soils sampled for three seasons. Soil microbial density generally increased in subplots of Eupatorium perfoliatum (boneset), Aster novae-angliae (New England aster), Andropogon gerardii (big bluestem), and Scirpus atrovirens (green bulrush) versus unplanted subplots. Using enumeration assays with root exudates, PAH degrading bacteria were greatest in soils beneath plants. Initially predominant, Arthrobacter were found capable of degrading a PAH cocktail in vitro, especially upon the addition of root exudate. Growth of some Arthrobacter isolates was stimulated by root exudate. The frequency of Arthrobacter declined in planted subplots with a concurrent increase in other species, including secondary PAH degraders Bacillus and Nocardioides. In subplots supporting only weeds, an increase in Pseudomonas density and little PAH removal were observed. This study supports the notion that a dynamic interplay between the soil, bacteria, and native plant root secretions likely contributes to in situ PAH phytoremediation.

  10. Bacterial biodegradation of melamine-contaminated aged soil: influence of different pre-culture media or addition of activation material.

    Science.gov (United States)

    Hatakeyama, Takashi; Takagi, Kazuhiro

    2016-08-01

    This study aimed to investigate the biodegrading potential of Arthrobacter sp. MCO, Arthrobacter sp. CSP, and Nocardioides sp. ATD6 in melamine-contaminated upland soil (melamine: approx. 10.5 mg/kg dry weight) after 30 days of incubation. The soil sample used in this study had undergone annual treatment of lime nitrogen, which included melamine; it was aged for more than 10 years in field. When R2A broth was used as the pre-culture medium, Arthrobacter sp. MCO could degrade 55 % of melamine after 30 days of incubation, but the other strains could hardly degrade melamine (approximately 25 %). The addition of trimethylglycine (betaine) in soil as an activation material enhanced the degradation rate of melamine by each strain; more than 50 % of melamine was degraded by all strains after 30 days of incubation. In particular, strain MCO could degrade 72 % of melamine. When the strains were pre-cultured in R2A broth containing melamine, the degradation rate of melamine in soil increased remarkably. The highest (72 %) melamine degradation rate was noted when strain MCO was used with betaine addition.

  11. Diversity, metal resistance and uranium sequestration abilities of bacteria from uranium ore deposit in deep earth stratum.

    Science.gov (United States)

    Islam, Ekramul; Sar, Pinaki

    2016-05-01

    Metal resistance and uranium (U) sequestration abilities of bacteria residing in subsurface U ore was investigated using 122 pure culture strains isolated through enrichment. The cumulative frequencies of isolates resistant to each metal tested were as follows: As(V), 74%; Zn, 58%; Ni, 53%; Cd, 47%; Cr(VI), 41%; Co, 40%; Cu, 20%; and Hg, 4%. 16S rRNA gene analysis revealed that isolated bacteria belonged to 14 genera with abundance of Arthrobacter, Microbacterium, Acinetobacter and Stenotrophomonas. Cobalt did not interfere with the growth of most of the bacterial isolates belonging to different groups while U allowed growth of four different genera of which Stenotrophomonas and Microbacterium showed high U tolerance. Interestingly, tolerance to Ni, Zn, Cu, and Hg was observed only in Microbacterium, Arthrobacter, Paenibacillus¸ and Acinetobacter, respectively. However, Microbacterium was found to be dominant when isolated from other five different metal enrichments including U. Uranium removal study showed that 84% of the test bacteria could remove more than 50mgUg(-1) dry weight from 80 or 160mgL(-1) U within 48h. In general, Microbacterium, Arthrobacter and Acinetobacter could remove a higher amount of U. High resolution transmission electron microscopy (HRTEM) study of U exposed cells revealed that accumulated U sequestered mostly around the cell periphery. The study highlights that indigenous U ore deposit bacteria have the potential to interact with U, and thus could be applied for bioremediation of U contaminated sites or wastes. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Metabolic versatility of Gram-positive microbial isolates from contaminated river sediments

    International Nuclear Information System (INIS)

    Narancic, Tanja; Djokic, Lidija; Kenny, Shane T.; O’Connor, Kevin E.; Radulovic, Vanja; Nikodinovic-Runic, Jasmina; Vasiljevic, Branka

    2012-01-01

    Highlights: ► Thirty-four isolated Gram-positive bacteria could degrade wide range of aromatic pollutants. ► Nine isolates could grow in the presence of extremely high levels of heavy metals. ► Twelve isolates accumulated polyphosphate, 3 polyhydroxybutyrate, 4 exopolysaccharides. ► The incidence of multiple antibiotic resistance markers among isolates was low. - Abstract: Gram-positive bacteria from river sediments affected by the proximity of a petrochemical industrial site were isolated and characterized with respect to their ability to degrade a wide range of aromatic compounds. In this study we identified metabolically diverse Gram-positive bacteria capable of growth on wide range aromatic compounds in the presence of heavy metals and with the ability to accumulate biopolymers. Thirty-four isolates that were able to use 9 or more common aromatic pollutants, such as benzene, biphenyl, naphthalene etc. as a sole source of carbon and energy included members of Bacillus, Arthrobacter, Rhodococcus, Gordonia, Streptomyces, and Staphylococcus genus. Rhodococcus sp. TN105, Gordonia sp. TN103 and Arthrobacter sp. TN221 were identified as novel strains. Nine isolates were able to grow in the presence of one or more metals (mercury, cadmium, nickel) at high concentration (100 mM). Seven isolates could degrade 15 different aromatic compounds and could grow in the presence of one or more heavy metals. Two of these isolates were resistant to multiple antibiotics including erythromycin and nalidixic acid. One third of isolates could accumulate at least one biopolymer. Twelve isolates (mainly Bacillus sp. and Arthrobacter sp.) accumulated polyphosphate, 3 Bacillus sp. accumulated polyhydroxybutyrate, while 4 isolates could accumulate exopolysaccharides.

  13. Bioremediation of soil with diesel Through the use of autochthonous microorganisms

    International Nuclear Information System (INIS)

    Arrieta Ramirez, Olga Maria; Rivera Rivera, Angela Patricia; Arias Marin, Lida; Rojano, Benjamin Alberto; Ruiz, Orlando; Cardona Gallo, Santiago Alonso

    2012-01-01

    In this study was isolated and characterized biochemical and molecular a bacterial consortium able to degrade hydrocarbons several, comprised of the following genres: Enterobacter sp, Bacillus sp, Staphylococcus aureus, Sanguibacter soli, Arthrobacter spy Flavobacterium sp, from soil contaminated with diesel fuel in a laboratory scale, and treated with two technologies for bioremediation: natural attenuation and biostimulation. We obtained a reduction in the concentration of Total Petroleum Hydrocarbons (TPH) in a period of 4 months was 36,86% for natural attenuation and 50,99% for biostimulation.

  14. [Formation of microbial populations on the surface of protective coatings].

    Science.gov (United States)

    Kopteva, Zh P; Zanina, V V; Piliashenko-Novokhatnyĭ, A I; Kopteva, A E; Kozlova, I A

    2001-01-01

    Formation of microbial cenosis on the surface of polyethylene-, polyurethane- and oil-bitumen-based protective coatings was studied in dynamics during 1, 3, 7, 14 and 21 days. It has been shown that the biofilm was formed on the protective materials during 14 days and consisted of ammonifying, denitrifying, hydrocarbon-oxidizing and sulphate-reducing bacteria referred to Pseudomonas, Arthrobacter, Bacillus and Kesulfovibrio genera. The bacteria which form the biofilm on coatings possess high denitrifying and sulphate-reducing activities. Corrosion inhibitors-biocydes, introduced in composition of oil-bitumen coatings suppressed growth and metabolic activity of corrosion-active bacteria.

  15. The rapid isolation of mutants of some Gram-positive bacteria

    International Nuclear Information System (INIS)

    Dijkhuizen, L.; Keijer, L.

    1981-01-01

    In this communication the authors describe a method for isolating at high frequency independent mutants of a number of Gram-positive bacteria. The method was originally developed for use with an Arthrobacter sp. and appears to work best with this and other coryneform bacteria. All the bacteria used were from the culture collections maintained at the University of Warwick or the Centre for Applied Microbiological Research. For mutagenesis using UV light, cells were grown in complex media and used while still in the logarithmic phase of growth. Details of the irradiation procedure are given in the text. (Auth.)

  16. X-ray photoelectron spectroscopic evidence for bacteria-enhanced dissolution of hornblende

    Science.gov (United States)

    Kalinowski, B. E.; Liermann, L. J.; Brantley, S. L.; Barnes, A.; Pantano, C. G.

    2000-04-01

    An Arthrobacter species capable of extracting Fe from hornblende was isolated from a soil from the Adirondacks, NY (USA). This bacteria isolate, used in batch experiments with hornblende, accelerated the release of Fe from hornblende without measurably affecting Al release. The isolate produces both low molecular weight organic acids (LMWOA) and a catecholate siderophore. Polished hornblende (glass and crystal) discs were analyzed with X-ray photoelectron spectroscopy (XPS) before and after incubation with growing Arthrobacter sp. to investigate whether the bacteria caused a distinguishable chemical signature on the upper 100 Å of mineral surface. After removal of the arthrobacter grown on hornblende crystal or glass substrates using lysozyme, XPS revealed surface depletion of Fe for samples grown for several days in buffered (crystal) and unbuffered (crystal and glass) media. Fe/Si ratios of hornblende surfaces dissolved under biotic conditions are significantly lower than Fe/Si ratios on surfaces dissolved under abiotic conditions for similar amounts of time. Enhanced Fe release and the formation of Fe-depleted surfaces is inferred to be caused by catechol complexation at the mineral surface. Because natural siderophore was not isolated in sufficient quantities to run bacteria-free leaching experiments, parallel investigations were run with a commercially available siderophore (desferrioxamine B). Desferrioxamine B was observed to enhance release of Fe, Si, and Al from hornblende both with and without added bacteria. Formation of desferrioxamine-Fe surface complexes were probed by studying the multiple splitting and shift in intensities of the N 1s line analyzed by XPS on siderophore ± Fe on gold surfaces and siderophore + hornblende crystal surfaces. Based upon the observed formation of an hydroxamate (desferrioxamine) surface complex on hornblende, we infer that catecholate siderophores, such as those produced by the arthrobacter, also complex on the

  17. Bacterial flora of soil after application of oily waste

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, V

    1975-01-01

    The influence of mineral oils and oily waste on the bacterial flora of soil was studied both in the field and in model experiments by plate counts followed by examination of the composition of the bacterial flora developing on the plates and by enrichment cultures followed by isolation of pure cultures. A strong increase in bacterial numbers after oil application was observed both in field and model experiments, and this increase occurred within all groups of bacteria, except spore formers and streptomycetes. The most important species of oil decomposing bacteria belonged to the genera Arthrobacter and Pseudomonas.

  18. Occurrence, diversity and community structure of culturable atrazine degraders in industrial and agricultural soils exposed to the herbicide in Shandong Province, P.R. China.

    Science.gov (United States)

    Bazhanov, Dmitry P; Li, Chengyun; Li, Hongmei; Li, Jishun; Zhang, Xinjian; Chen, Xiangfeng; Yang, Hetong

    2016-11-08

    Soil populations of bacteria rapidly degrading atrazine are critical to the environmental fate of the herbicide. An enrichment bias from the routine isolation procedure prevents studying the diversity of atrazine degraders. In the present work, we analyzed the occurrence, diversity and community structure of soil atrazine-degrading bacteria based on their direct isolation. Atrazine-degrading bacteria were isolated by direct plating on a specially developed SM agar. The atrazine degradation genes trzN and atzABC were detected by multiplex PCR. The diversity of atrazine degraders was characterized by enterobacterial repetitive intergenic consensus-PCR (ERIC-PCR) genotyping followed by 16S rRNA gene phylogenetic analysis. The occurrence of atrazine-degrading bacteria was also assessed by conventional PCR targeting trzN and atzABC in soil DNA. A total of 116 atrazine-degrading isolates were recovered from bulk and rhizosphere soils sampled near an atrazine factory and from geographically distant maize fields. Fifteen genotypes were distinguished among 56 industrial isolates, with 13 of them representing eight phylogenetic groups of the genus Arthrobacter. The remaining two were closely related to Pseudomonas alcaliphila and Gulosibacter molinativorax and constituted major components of the atrazine-degrading community in the most heavily contaminated industrial plantless soil. All isolates from the adjacent sites inhabited by cogon grass or common reed were various Arthrobacter spp. with a strong prevalence of A. aurescens group. Only three genotypes were distinguished among 60 agricultural strains. Genetically similar Arthrobacter ureafaciens bacteria which occurred as minor inhabitants of cogon grass roots in the industrial soil were ubiquitous and predominant atrazine degraders in the maize rhizosphere. The other two genotypes represented two distant Nocardioides spp. that were specific to their geographic origins. Direct plating on SM agar enabled rapid isolation

  19. Global patterns of marine bacterioplankton diversity and characterisation of bioactive Vibrionaceae isolates

    DEFF Research Database (Denmark)

    Wietz, Matthias

    from P. halotolerans and a novel siderophore-like compound from V. nigripulchritudo were isolated. All three compounds interfere with quorum sensing in S. aureus. During LOMROG-II further seventeen strains with antagonistic activity were isolated, affiliating with the Actinobacteria (8 strains......), Pseudoalteromonas (4 strains), the Vibrionaceae (3 strains), and Psychrobacter (2 strains). Seven of the eight bioactive Actinobacteria, being isolated from different sources throughout the Arctic Ocean, were related to Arthrobacter davidanieli. Its broad antibiotic spectrum was likely based on production...... demonstrated that marine Vibrionaceae and polar Actinobacteria are a resource of antibacterial compounds and may have potential for future natural product discovery....

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

    International Nuclear Information System (INIS)

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

    1999-01-01

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

  1. Enhanced mineralization of diuron using a cyclodextrin-based bioremediation technology.

    Science.gov (United States)

    Villaverde, Jaime; Posada-Baquero, Rosa; Rubio-Bellido, Marina; Laiz, Leonila; Saiz-Jimenez, Cesareo; Sanchez-Trujillo, María A; Morillo, Esmeralda

    2012-10-10

    The phenylurea herbicide diuron [N-(3,4-dichlorophenyl)-N,N-dimethylurea] is widely used in a broad range of herbicide formulations and, consequently, it is frequently detected as a major soil and water contaminant in areas where there is extensive use. Diuron has the unfortunate combination of being strongly adsorbed by soil organic matter particles and, hence, slowly degraded in the environment due to its reduced bioavailability. N-Phenylurea herbicides seem to be biodegraded in soil, but it must be kept in mind that this biotic or abiotic degradation could lead to accumulation of very toxic derived compounds, such as 3,4-dichloroaniline. Research was conducted to find procedures that might result in an increase in the bioavailability of diuron in contaminated soils, through solubility enhancement. For this purpose a double system composed of hydroxypropyl-β-cyclodextrin (HPBCD), which is capable of forming inclusion complexes in solution, and a two-member bacterial consortium formed by the diuron-degrading Arthrobacter sulfonivorans (Arthrobacter sp. N2) and the linuron-degrading Variovorax soli (Variovorax sp. SRS16) was used. This consortium can achieve a complete biodegradation of diuron to CO2 with regard to that observed in the absence of the CD solution, where only a 45% biodegradation was observed. The cyclodextrin-based bioremediation technology here described shows for the first time an almost complete mineralization of diuron in a soil system, in contrast to previous incomplete mineralization based on single or consortium bacterial degradation.

  2. Significant relationship between soil bacterial community structure and incidence of bacterial wilt disease under continuous cropping system.

    Science.gov (United States)

    She, Siyuan; Niu, Jiaojiao; Zhang, Chao; Xiao, Yunhua; Chen, Wu; Dai, Linjian; Liu, Xueduan; Yin, Huaqun

    2017-03-01

    Soil bacteria are very important in biogeochemical cycles and play significant role in soil-borne disease suppression. Although continuous cropping is responsible for soil-borne disease enrichment, its effect on tobacco plant health and how soil bacterial communities change are yet to be elucidated. In this study, soil bacterial communities across tobacco continuous cropping time-series fields were investigated through high-throughput sequencing of 16S ribosomal RNA genes. The results showed that long-term continuous cropping could significantly alter soil microbial communities. Bacterial diversity indices and evenness indices decreased over the monoculture span and obvious variations for community structures across the three time-scale tobacco fields were detected. Compared with the first year, the abundances of Arthrobacter and Lysobacter showed a significant decrease. Besides, the abundance of the pathogen Ralstonia spp. accumulated over the monoculture span and was significantly correlated with tobacco bacterial wilt disease rate. Moreover, Pearson's correlation demonstrated that the abundance of Arthrobacter and Lysobacter, which are considered to be beneficial bacteria had significant negative correlation with tobacco bacterial wilt disease. Therefore, after long-term continuous cropping, tobacco bacterial wilt disease could be ascribed to the alteration of the composition as well as the structure of the soil microbial community.

  3. Deep subsurface life from North Pond: enrichment, isolation, characterization and genomes of heterotrophic bacteria

    Directory of Open Access Journals (Sweden)

    Joseph A. Russell

    2016-05-01

    Full Text Available Studies of subsurface microorganisms have yielded few environmentally relevant isolates for laboratory studies. In order to address this lack of cultivated microorganisms, we initiated several enrichments on sediment and underlying basalt samples from North Pond, a sediment basin ringed by basalt outcrops underlying an oligotrophic water-column west of the Mid-Atlantic Ridge at 22°N. In contrast to anoxic enrichments, growth was observed in aerobic, heterotrophic enrichments from sediment of IODP site U1382B at 4 and 68 meters below seafloor (mbsf. These sediment depths, respectively, correspond to the fringes of oxygen penetration from overlying seawater in the top of the sediment column and upward migration of oxygen from oxic seawater from the basalt aquifer below the sediment. Here we report the enrichment, isolation, and initial characterizations of three isolated aerobic heterotrophs from North Pond sediments; an Arthrobacter species from 4 mbsf, and Paracoccus and Pseudomonas species from 68 mbsf. These cultivated bacteria are represented in the amplicon 16S rRNA gene libraries created from whole sediments, albeit at low (up to 2% relative abundance. We provide genomic evidence from our isolates demonstrating that the Arthrobacter and Pseudomonas isolates have the potential to respire nitrate and oxygen, though dissimilatory nitrate reduction could not be confirmed in laboratory cultures. The cultures from this study represent members of environmentally significant phyla, and allow for further studies into geochemical factors impacting life in the deep subsurface.

  4. Deep Subsurface Life from North Pond: Enrichment, Isolation, Characterization and Genomes of Heterotrophic Bacteria.

    Science.gov (United States)

    Russell, Joseph A; León-Zayas, Rosa; Wrighton, Kelly; Biddle, Jennifer F

    2016-01-01

    Studies of subsurface microorganisms have yielded few environmentally relevant isolates for laboratory studies. In order to address this lack of cultivated microorganisms, we initiated several enrichments on sediment and underlying basalt samples from North Pond, a sediment basin ringed by basalt outcrops underlying an oligotrophic water-column west of the Mid-Atlantic Ridge at 22°N. In contrast to anoxic enrichments, growth was observed in aerobic, heterotrophic enrichments from sediment of IODP Hole U1382B at 4 and 68 m below seafloor (mbsf). These sediment depths, respectively, correspond to the fringes of oxygen penetration from overlying seawater in the top of the sediment column and upward migration of oxygen from oxic seawater from the basalt aquifer below the sediment. Here we report the enrichment, isolation, initial characterization and genomes of three isolated aerobic heterotrophs from North Pond sediments; an Arthrobacter species from 4 mbsf, and Paracoccus and Pseudomonas species from 68 mbsf. These cultivated bacteria are represented in the amplicon 16S rRNA gene libraries created from whole sediments, albeit at low (up to 2%) relative abundance. We provide genomic evidence from our isolates demonstrating that the Arthrobacter and Pseudomonas isolates have the potential to respire nitrate and oxygen, though dissimilatory nitrate reduction could not be confirmed in laboratory cultures. The cultures from this study represent members of abundant phyla, as determined by amplicon sequencing of environmental DNA extracts, and allow for further studies into geochemical factors impacting life in the deep subsurface.

  5. Profile of microbial communities on carbonate stones of the medieval church of San Leonardo di Siponto (Italy) by Illumina-based deep sequencing.

    Science.gov (United States)

    Chimienti, Guglielmina; Piredda, Roberta; Pepe, Gabriella; van der Werf, Inez Dorothé; Sabbatini, Luigia; Crecchio, Carmine; Ricciuti, Patrizia; D'Erchia, Anna Maria; Manzari, Caterina; Pesole, Graziano

    2016-10-01

    Comprehensive studies of the biodiversity of the microbial epilithic community on monuments may provide critical insights for clarifying factors involved in the colonization processes. We carried out a high-throughput investigation of the communities colonizing the medieval church of San Leonardo di Siponto (Italy) by Illumina-based deep sequencing. The metagenomic analysis of sequences revealed the presence of Archaea, Bacteria, and Eukarya. Bacteria were Actinobacteria, Proteobacteria, Bacteroidetes, Cyanobacteria, Chloroflexi, Firmicutes and Candidatus Saccharibacteria. The predominant phylum was Actinobacteria, with the orders Actynomycetales and Rubrobacteriales, represented by the genera Pseudokineococcus, Sporichthya, Blastococcus, Arthrobacter, Geodermatophilus, Friedmanniella, Modestobacter, and Rubrobacter, respectively. Cyanobacteria sequences showing strong similarity with an uncultured bacterium sequence were identified. The presence of the green algae Oocystaceae and Trebuxiaceae was revealed. The microbial diversity was explored at qualitative and quantitative levels, evaluating the richness (the number of operational taxonomic units (OTUs)) and the abundance of reads associated with each OTU. The rarefaction curves approached saturation, suggesting that the majority of OTUs were recovered. The results highlighted a structured community, showing low diversity, made up of extremophile organisms adapted to desiccation and UV radiation. Notably, the microbiome appeared to be composed not only of microorganisms possibly involved in biodeterioration but also of carbonatogenic bacteria, such as those belonging to the genus Arthrobacter, which could be useful in bioconservation. Our investigation demonstrated that molecular tools, and in particular the easy-to-run next-generation sequencing, are powerful to perform a microbiological diagnosis in order to plan restoration and protection strategies.

  6. Combined endophytic inoculants enhance nickel phytoextraction from serpentine soil in the hyperaccumulator Noccaea caerulescens.

    Science.gov (United States)

    Visioli, Giovanna; Vamerali, Teofilo; Mattarozzi, Monica; Dramis, Lucia; Sanangelantoni, Anna M

    2015-01-01

    This study assesses the effects of specific bacterial endophytes on the phytoextraction capacity of the Ni-hyperaccumulator Noccaea caerulescens, spontaneously growing in a serpentine soil environment. Five metal-tolerant endophytes had already been selected for their high Ni tolerance (6 mM) and plant growth promoting ability. Here we demonstrate that individual bacterial inoculation is ineffective in enhancing Ni translocation and growth of N. caerulescens in serpentine soil, except for specific strains Ncr-1 and Ncr-8, belonging to the Arthrobacter and Microbacterium genera, which showed the highest indole acetic acid production and 1-aminocyclopropane-1-carboxylic acid-deaminase activity. Ncr-1 and Ncr-8 co-inoculation was even more efficient in promoting plant growth, soil Ni removal, and translocation of Ni, together with that of Fe, Co, and Cu. Bacteria of both strains densely colonized the root surfaces and intercellular spaces of leaf epidermal tissue. These two bacterial strains also turned out to stimulate root length, shoot biomass, and Ni uptake in Arabidopsis thaliana grown in MS agar medium supplemented with Ni. It is concluded that adaptation of N. caerulescens in highly Ni-contaminated serpentine soil can be enhanced by an integrated community of bacterial endophytes rather than by single strains; of the former, Arthrobacter and Microbacterium may be useful candidates for future phytoremediation trials in multiple metal-contaminated sites, with possible extension to non-hyperaccumulator plants.

  7. Combined endophytic inoculants enhance nickel phytoextraction from serpentine soil in the hyperaccumulator Noccaea caerulescens

    Directory of Open Access Journals (Sweden)

    Giovanna eVisioli

    2015-08-01

    Full Text Available This study assesses the effects of specific bacterial endophytes on the phytoextraction capacity of the Ni-hyperaccumulator Noccaea caerulescens, spontaneously growing in a serpentine soil environment. Five metal-tolerant endophytes had already been selected for their high Ni tolerance (6 mM and plant growth promoting ability. Here we demonstrate that individual bacterial inoculation is ineffective in enhancing Ni translocation and growth of N. caerulescens in serpentine soil, except for specific strains Ncr-1 and Ncr-8, belonging to the Arthrobacter and Microbacterium genera, which showed the highest IAA production and ACC-deaminase activity. Ncr-1 and Ncr-8 co-inoculation was even more efficient in promoting plant growth, soil Ni removal and translocation of Ni, together with that of Fe, Co and Cu. Bacteria of both strains densely colonised the root surfaces and intercellular spaces of leaf epidermal tissue. These two bacterial strains also turned out to stimulate root length, shoot biomass and Ni uptake in Arabidopsis thaliana grown in MS agar medium supplemented with Ni. It is concluded that adaptation of N. caerulescens in highly Ni-contaminated serpentine soil can be enhanced by an integrated community of bacterial endophytes rather than by single strains; of the former, Arthrobacter and Microbacterium may be useful candidates for future phytoremediation trials

  8. Uranium and other heavy metal resistance and accumulation in bacteria isolated from uranium mine wastes.

    Science.gov (United States)

    Choudhary, Sangeeta; Islam, Ekramul; Kazy, Sufia K; Sar, Pinaki

    2012-01-01

    Ten bacterial strains isolated from uranium mine wastes were characterized in terms of their uranium and other metal resistance and accumulation. 16S rRNA gene sequence analysis identified the strains as members of genera Bacillus, Serratia, and Arthrobacter. Strains were able to utilize various carbon sources, particularly aromatic hydrocarbons, grow at broad pH and temperature ranges and produce non specific acid phosphatase relevant for metal phosphate precipitation in contaminated environment. The isolates exhibited high uranium and other heavy metals (Ni, Co, Cu and Cd) resistance and accumulation capacities. Particularly, Arthrobacter sp. J001 and Bacillus sp. J003 were superior in terms of U resistance at low pH (pH 4.0) along with metals and actinides (U and Th) removal with maximum cell loading of 1088 μmol U, 1293 μmol Th, 425 μmol Cu, 305 μmol Cd, 377 μmol Zn, 250 μmol Ni g(-1) cell dry wt. Genes encoding P(1B)-type ATPases (Cu-CPx and Zn-CPx) and ABC transporters (nik) as catalytic tools for maintaining cellular metal homeostasis were detected within several Bacillus spp., with possible incidence of horizontal gene transfer for the later gene showing phylogenetic lineage to α Proteobacteria members. The study provides evidence on intrinsic abilities of indigenous bacteria from U-mine suitable for survival and cleaning up of contaminated mine sites.

  9. Phylogenetic Analysis and Antimicrobial Profiles of Cultured Emerging Opportunistic Pathogens (Phyla Actinobacteria and Proteobacteria) Identified in Hot Springs.

    Science.gov (United States)

    Jardine, Jocelyn Leonie; Abia, Akebe Luther King; Mavumengwana, Vuyo; Ubomba-Jaswa, Eunice

    2017-09-15

    Hot spring water may harbour emerging waterborne opportunistic pathogens that can cause infections in humans. We have investigated the diversity and antimicrobial resistance of culturable emerging and opportunistic bacterial pathogens, in water and sediment of hot springs located in Limpopo, South Africa. Aerobic bacteria were cultured and identified using 16S ribosomal DNA (rDNA) gene sequencing. The presence of Legionella spp. was investigated using real-time polymerase chain reaction. Isolates were tested for resistance to ten antibiotics representing six different classes: β-lactam (carbenicillin), aminoglycosides (gentamycin, kanamycin, streptomycin), tetracycline, amphenicols (chloramphenicol, ceftriaxone), sulphonamides (co-trimoxazole) and quinolones (nalidixic acid, norfloxacin). Gram-positive Kocuria sp. and Arthrobacter sp. and gram-negative Cupriavidus sp., Ralstonia sp., Cronobacter sp., Tepidimonas sp., Hafnia sp. and Sphingomonas sp. were isolated, all recognised as emerging food-borne pathogens. Legionella spp. was not detected throughout the study. Isolates of Kocuria , Arthrobacter and Hafnia and an unknown species of the class Gammaproteobacteria were resistant to two antibiotics in different combinations of carbenicillin, ceftriaxone, nalidixic acid and chloramphenicol. Cronobacter sp. was sensitive to all ten antibiotics. This study suggests that hot springs are potential reservoirs for emerging opportunistic pathogens, including multiple antibiotic resistant strains, and highlights the presence of unknown populations of emerging and potential waterborne opportunistic pathogens in the environment.

  10. Coral-Associated Actinobacteria: Diversity, Abundance, and Biotechnological Potentials

    Science.gov (United States)

    Mahmoud, Huda M.; Kalendar, Aisha A.

    2016-01-01

    Marine Actinobacteria, particularly coral-associated Actinobacteria, have attracted attention recently. In this study, the abundance and diversity of Actinobacteria associated with three types of coral thriving in a thermally stressed coral reef system north of the Arabian Gulf were investigated. Coscinaraea columna, Platygyra daedalea and Porites harrisoni have been found to harbor equivalent numbers of culturable Actinobacteria in their tissues but not in their mucus. However, different culturable actinobacterial communities have been found to be associated with different coral hosts. Differences in the abundance and diversity of Actinobacteria were detected between the mucus and tissue of the same coral host. In addition, temporal and spatial variations in the abundance and diversity of the cultivable actinobacterial communities were detected. In total, 19 different actinobacterial genera, namely Micrococcus, Brachybacterium, Brevibacterium, Streptomyces, Micromonospora, Renibacterium, Nocardia, Microbacterium, Dietzia, Cellulomonas, Ornithinimicrobium, Rhodococcus, Agrococcus, Kineococcus, Dermacoccus, Devriesea, Kocuria, Marmoricola, and Arthrobacter, were isolated from the coral tissue and mucus samples. Furthermore, 82 isolates related to Micromonospora, Brachybacterium, Nocardia, Micrococcus, Arthrobacter, Rhodococcus, and Streptomyces showed antimicrobial activities against representative Gram-positive and/or Gram-negative bacteria. Even though Brevibacterium and Kocuria were the most dominant actinobacterial isolates, they failed to show any antimicrobial activity, whereas less dominant genera, such as Streptomyces, did show antimicrobial activity. Focusing on the diversity of coral-associated Actinobacteria may help to understand how corals thrive under harsh environmental conditions and may lead to the discovery of novel antimicrobial metabolites with potential biotechnological applications. PMID:26973601

  11. Investigation on Microbial Dissolution of Uranium (VI) from Autunite Mineral - 13421

    Energy Technology Data Exchange (ETDEWEB)

    Sepulveda, Paola; Katsenovich, Yelena; Lagos, Leonel [Applied Research Center, Florida International University. 10555 West Flagler St. Suite 2100, Miami Fl 33175 (United States)

    2013-07-01

    Precipitating autunite minerals by polyphosphate injection was identified as a feasible remediation strategy for sequestering uranium in contaminated groundwater and soil in situ at the Hanford Site. Autunite stability under vadose and saturated zone environmental conditions can help to determine the long-term effectiveness of this remediation strategy. The Arthrobacter bacteria are one of the most common groups in soils and are found in large numbers in Hanford soil as well as other subsurface environments contaminated with radionuclides. Ubiquitous in subsurface microbial communities, these bacteria can play a significant role in the dissolution of minerals and the formation of secondary minerals. The main objective of this investigation was to study the bacterial interactions under oxidizing conditions with uranium (VI); study the potential role of bicarbonate, which is an integral complexing ligand for U(VI) and a major ion in groundwater compositions; and present data from autunite dissolution experiments using Arthrobacter strain G968, a less U(VI)-tolerant strain. Sterile 100 mL glass mixed reactors served as the major bioreactor for initial experimentation. These autunite-containing bioreactors were injected with bacterial cells after the autunite equilibrated with the media solution amended with 0 mM, 3 mM 5 mM and 10 mM concentrations of bicarbonate. G968 Arthrobacter cells in the amount of 10{sup 6} cells/mL were injected into the reactors after 27 days, giving time for the autunite to reach steady state. Abiotic non-carbonate controls were kept without bacterial inoculation to provide a control for the biotic samples. Samples of the solution were analyzed for dissolved U(VI) by means of kinetic phosphorescence analyzer KPA-11 (Chemcheck Instruments, Richland, WA). Analysis showed that as [HCO{sub 3}{sup -}] increases, a diminishing trend on the effect of bacteria on autunite leaching is observed. Viability of cells was conducted after 24 hours of cell

  12. Investigation on Microbial Dissolution of Uranium (VI) from Autunite Mineral - 13421

    International Nuclear Information System (INIS)

    Sepulveda, Paola; Katsenovich, Yelena; Lagos, Leonel

    2013-01-01

    Precipitating autunite minerals by polyphosphate injection was identified as a feasible remediation strategy for sequestering uranium in contaminated groundwater and soil in situ at the Hanford Site. Autunite stability under vadose and saturated zone environmental conditions can help to determine the long-term effectiveness of this remediation strategy. The Arthrobacter bacteria are one of the most common groups in soils and are found in large numbers in Hanford soil as well as other subsurface environments contaminated with radionuclides. Ubiquitous in subsurface microbial communities, these bacteria can play a significant role in the dissolution of minerals and the formation of secondary minerals. The main objective of this investigation was to study the bacterial interactions under oxidizing conditions with uranium (VI); study the potential role of bicarbonate, which is an integral complexing ligand for U(VI) and a major ion in groundwater compositions; and present data from autunite dissolution experiments using Arthrobacter strain G968, a less U(VI)-tolerant strain. Sterile 100 mL glass mixed reactors served as the major bioreactor for initial experimentation. These autunite-containing bioreactors were injected with bacterial cells after the autunite equilibrated with the media solution amended with 0 mM, 3 mM 5 mM and 10 mM concentrations of bicarbonate. G968 Arthrobacter cells in the amount of 10 6 cells/mL were injected into the reactors after 27 days, giving time for the autunite to reach steady state. Abiotic non-carbonate controls were kept without bacterial inoculation to provide a control for the biotic samples. Samples of the solution were analyzed for dissolved U(VI) by means of kinetic phosphorescence analyzer KPA-11 (Chemcheck Instruments, Richland, WA). Analysis showed that as [HCO 3 - ] increases, a diminishing trend on the effect of bacteria on autunite leaching is observed. Viability of cells was conducted after 24 hours of cell incubation with

  13. Biosurfactants, bioemulsifiers and exopolysaccharides from marine microorganisms.

    Science.gov (United States)

    Satpute, Surekha K; Banat, Ibrahim M; Dhakephalkar, Prashant K; Banpurkar, Arun G; Chopade, Balu A

    2010-01-01

    Marine biosphere offers wealthy flora and fauna, which represents a vast natural resource of imperative functional commercial grade products. Among the various bioactive compounds, biosurfactant (BS)/bioemulsifiers (BE) are attracting major interest and attention due to their structural and functional diversity. The versatile properties of surface active molecules find numerous applications in various industries. Marine microorganisms such as Acinetobacter, Arthrobacter, Pseudomonas, Halomonas, Myroides, Corynebacteria, Bacillus, Alteromonas sp. have been studied for production of BS/BE and exopolysaccharides (EPS). Due to the enormity of marine biosphere, most of the marine microbial world remains unexplored. The discovery of potent BS/BE producing marine microorganism would enhance the use of environmental biodegradable surface active molecule and hopefully reduce total dependence or number of new application oriented towards the chemical synthetic surfactant industry. Our present review gives comprehensive information on BS/BE which has been reported to be produced by marine microorganisms and their possible potential future applications.

  14. Biotransformation of isoeugenol to vanillin by Pseudomonas putida IE27 cells.

    Science.gov (United States)

    Yamada, Mamoru; Okada, Yukiyoshi; Yoshida, Toyokazu; Nagasawa, Toru

    2007-01-01

    The ability to produce vanillin and/or vanillic acid from isoeugenol was screened using resting cells of various bacteria. The vanillin- and/or vanillic-acid-producing activities were observed in strains belonging to the genera Achromobacter, Aeromonas, Agrobacerium, Alcaligenes, Arthrobacter, Bacillus, Micrococcus, Pseudomonas, Rhodobacter, and Rhodococcus. Strain IE27, a soil isolate showing the highest vanillin-producing activity, was identified as Pseudomonas putida. We optimized the culture and reaction conditions for vanillin production from isoeugenol using P. putida IE27 cells. The vanillin-producing activity was induced by adding isoeugenol to the culture medium but not vanillin or eugenol. Under the optimized reaction conditions, P. putida IE27 cells produced 16.1 g/l vanillin from 150 mM isoeugenol, with a molar conversion yield of 71% at 20 degrees C after a 24-h incubation in the presence of 10% (v/v) dimethyl sulfoxide.

  15. Molecular and phenotypic characterization of endophytic bacteria isolated from sulla nodules.

    Science.gov (United States)

    Beghalem, Hamida; Aliliche, Khadidja; Chriki, Ali; Landoulsi, Ahmed

    2017-10-01

    In the current study, bacterial diversity was investigated in root nodules of Sulla pallida and Sulla capitata. The isolates were analyzed on the basis of their phenotypic and molecular characteristics. The phylogenetic analysis based on 16S rRNA and housekeeping genes (recA and atpD) showed that the isolated bacteria related to Sinorhizobium, Neorhizobium, Phyllobacterium, Arthrobacter, Variovorax and Pseudomonas genera. This is the first report of Neorhizobium genus associated with Hedysarum genus. Phenotypically, all strains tolerate the elevated temperature of 40 °C, and salt stress at a concentration of 2%. In addition, the isolates failed to induce nodulation on their original host; and the symbiotic genes could not be amplified, suggesting that these strains are endophytic bacteria. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Nitrogen starvation affects bacterial adhesion to soil Adesão de bactérias desnutridas por nitrogênio a solo

    Directory of Open Access Journals (Sweden)

    Maria Tereza Borges

    2008-09-01

    Full Text Available One of the main factors limiting the bioremediation of subsoil environments based on bioaugmentation is the transport of selected microorganisms to the contaminated zones. The characterization of the physiological responses of the inoculated microorganisms to starvation, especially the evaluation of characteristics that affect the adhesion of the cells to soil particles, is fundamental to anticipate the success or failure of bioaugmentation. The objective of this study was to investigate the effect of nitrogen starvation on cell surface hydrophobicity and cell adhesion to soil particles by bacterial strains previously characterized as able to use benzene, toluene or xilenes as carbon and energy sources. The strains LBBMA 18-T (non-identified, Arthrobacter aurescens LBBMA 98, Arthrobacter oxydans LBBMA 201, and Klebsiella sp. LBBMA 204-1 were used in the experiments. Cultivation of the cells in nitrogen-deficient medium caused a significant reduction of the adhesion to soil particles by all the four strains. Nitrogen starvation also reduced significantly the strength of cell adhesion to the soil particles, except for Klebsiella sp. LBBMA 204-1. Two of the four strains showed significant reduction in cell surface hydrophobicity. It is inferred that the efficiency of bacterial transport through soils might be potentially increased by nitrogen starvation.Um dos principais fatores limitantes da biorremediação in situ de solos subterrâneos, baseada na bioaumentação, é o transporte dos microrganismos selecionados até o local contaminado. A caracterização das respostas fisiológicas dos microrganismos introduzidos no subsolo a condições de escassez nutricional, notadamente a avaliação de características que afetam a adesão celular ao solo, é fundamental para se prever o sucesso da bioaumentação. O objetivo deste trabalho foi determinar o efeito da desnutrição em meio com escassez de nitrogênio sobre a hidrofobicidade celular e a

  17. Microbial efficacy of phosphate solubilization in agro-saline soils of various areas of sindh region

    International Nuclear Information System (INIS)

    Noor, A.A.; Shah, F.A.

    2013-01-01

    Microorganisms are the most prominent entities for solubilization of phosphate in various soils of different areas of Sindh Province including Tando Muhammad Khan, Tando Allah Yar, Nawabshah, Rato Dero-Larkana, Shikarpur and Umer Kot. These soils, having varying concentrations of chemicals, different climatic conditions, pH and varying numbers of microorganisms for PSA (Phosphate Solubilization Activity). This presentation shows the isolation of different fungi and bacteria capable Psa including fungi (Fusarium sp. Aspergillus sp. Penicillium sp. and Rhizopus sp.) and bacteria (Bacillus sp. Pseudomonas sp. and Arthrobacter sp.). From the observations, it was revealed that fungi Aspergillus sp. and Bacillus sp. showed greater phosphate solubilization activity as compared to other fungi and bacteria showing 60 and 53.33% Psa (Phosphate Solubilizing Activity) respectively. (author)

  18. Ecological aspects of microorganisms inhabiting uranium mill tailings

    Science.gov (United States)

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

    1987-01-01

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

  19. Direct Cellular Lysis/Protein Extraction Protocol for Soil Metaproteomics

    Energy Technology Data Exchange (ETDEWEB)

    Chourey, Karuna [ORNL; Jansson, Janet [Lawrence Berkeley National Laboratory (LBNL); Verberkmoes, Nathan C [ORNL; Shah, Manesh B [ORNL; Chavarria, Krystle L. [Lawrence Berkeley National Laboratory (LBNL); Tom, Lauren M [Lawrence Berkeley National Laboratory (LBNL); Brodie, Eoin L. [Lawrence Berkeley National Laboratory (LBNL); Hettich, Robert {Bob} L [ORNL

    2010-01-01

    We present a novel direct protocol for deep proteome characterization of microorganisms in soil. The method employs thermally assisted detergent-based cellular lysis (SDS) of soil samples, followed by TCA precipitation for proteome extraction/cleanup prior to liquid chromatography-mass spectrometric characterization. This approach was developed and optimized using different soils inoculated with genome-sequenced bacteria (Gram-negative Pseudomonas putida or Gram-positive Arthrobacter chlorophenolicus). Direct soil protein extraction was compared to protein extraction from cells isolated from the soil matrix prior to lysis (indirect method). Each approach resulted in identification of greater than 500 unique proteins, with a wide range in molecular mass and functional categories. To our knowledge, this SDS-TCA approach enables the deepest proteome characterizations of microbes in soil to date, without significant biases in protein size, localization, or functional category compared to pure cultures. This protocol should provide a powerful tool for ecological studies of soil microbial communities.

  20. Effect of chromate action on morphology of basalt-inhabiting bacteria

    International Nuclear Information System (INIS)

    Lin Zhang; Zhu Ying; Kalabegishvili, Tamaz L.; Tsibakhashvili, Nelly Y.; Holman, Hoi-Ying

    2006-01-01

    Basalt-inhabiting bacteria isolated from polluted basalts have been demonstrated to be able to tolerate moderate to high concentrations of chromium oxyanions such as chromate. Previous results have shown that macromolecules outside the cell wall of bacteria may play an important role in this survival ability. In this paper, Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) were applied to study the chromate-induced morphological changes in chromate-resistant basalt-inhabiting Arthrobacter K-2 and K-4, which were isolated from the Republic of Georgia. The surfaces of both strains changed in the presence of chromate. TEM thin sections show that chromate stimulates the appearance of bacteria capsular polysaccharide outside the cell wall, although the chromate concentration does not have a strong effect on the capsular thickness. These results, in conjunction with those reported earlier, provide direct evidence to show that capsular polysaccharides of the bacteria play very important role for the reduction and localization of chromate

  1. Comparative study of plant growth promoting bacteria in minimizing toxic effects of chromium on growth and metabolic activities in wheat (triticum aestivum)

    International Nuclear Information System (INIS)

    Naseem, S.; Ahmed, A.; Yasin, M.

    2016-01-01

    In this study, effect of inoculation of five bacterial strains i.e., Kushneria avicenniae AHT, Halomonas sp. AST, Bacillus sp. AMP2, Halomonas venusta APA and Arthrobacter mysorens AHA on the growth of Triticum aestivum var. Inqilab 97 was observed under various concentrations (0, 10 and 20 mu gml-1) of different chromium salts (CrCl/sub 3/, K/sub 2/CrO/sub 4/, K/sub 2/Cr/sub 2/O/sub 7/). Bacterial inoculation caused reduction in the chromium uptake (22-32, 5-22 and 2-18%) of seedlings both at 10 and 20 mu g ml-1 CrCl3, K/sub 2/CrO/sub 4/ and K/sub 2/Cr/sub 2/O/sub 7/ when compared with respective non- inoculated treatment. Also increase in acid phosphatase and peroxidase contents was recorded due to bacterial inoculations compared to control. (author)

  2. New microbial growth factor

    Science.gov (United States)

    Bok, S. H.; Casida, L. E., Jr.

    1977-01-01

    A screening procedure was used to isolate from soil a Penicillium sp., two bacterial isolates, and a Streptomyces sp. that produced a previously unknown microbial growth factor. This factor was an absolute growth requirement for three soil bacteria. The Penicillium sp. and one of the bacteria requiring the factor, an Arthrobacter sp., were selected for more extensive study concerning the production and characteristics of the growth factor. It did not seem to be related to the siderochromes. It was not present in soil extract, rumen fluid, or any other medium component tested. It appears to be a glycoprotein of high molecular weight and has high specific activity. When added to the diets for a meadow-vole mammalian test system, it caused an increased consumption of diet without a concurrent increase in rate of weight gain.

  3. Lignite microorganisms

    Energy Technology Data Exchange (ETDEWEB)

    Bulankina, M.A.; Lysak, L.V.; Zvyagintsev, D.G. [Moscow MV Lomonosov State University, Moscow (Russian Federation). Faculty of Soil Science

    2007-03-15

    The first demonstration that samples of lignite at a depth of 10 m are considerably enriched in bacteria is reported. According to direct microscopy, the abundance of bacteria was about 10{sup 7} cells/g. About 70% of cells had intact cell membranes and small size, which points to their anabiotic state. The fungal mycelium length was no more than 1 m. Lignite inoculation onto solid glucose-yeast-peptone medium allowed us to isolate bacteria of the genera Bacillus, Rhodococcus, Arthrobacter, Micrococcus, Spirillum, and Cytophaga. Representatives of the genera Penicillium and Trichoderma were identified on Czapek medium. Moistening of lignite powder increased the microbial respiration rate and microbial and fungal abundance but did not increase their generic diversity. This finding suggests that the studied microorganisms are autochthonous to lignite.

  4. Interactions between yeasts and bacteria in the smear surface-ripened cheeses.

    Science.gov (United States)

    Corsetti, A; Rossi, J; Gobbetti, M

    2001-09-19

    In the initial phase of ripening, the microflora of bacterial smear surface-ripened cheeses such as Limburger, Taleggio, Brick, Münster and Saint-Paulin and that of surface mould-ripened cheeses such as Camembert and Brie may be similar, but at the end of the ripening, bacteria such as Brevibacterium spp., Arthrobacter spp., Micrococcus spp., Corynebacterium spp. and moulds such as Penicillium camemberti are, respectively, the dominant microorganisms. Yeasts such as Candida spp., Cryptococcus spp., Debaryomyces spp., Geotrichum candidum, Pichia spp., Rhodotorula spp., Saccharomyces spp. and Yarrowia lipolytica are often and variably isolated from the smear surface-ripened cheeses. Although not dominant within the microorganisms of the smear surface-ripened cheeses, yeasts establish significant interactions with moulds and especially bacteria, including surface bacteria and lactic acid bacteria. Some aspects of the interactions between yeasts and bacteria in such type of cheeses are considered in this paper.

  5. Changes in the structure of bacterial complexes of vegetable crops in the course of their growth on a cultivated soddy-podzolic soil

    Science.gov (United States)

    Dobrovol'skaya, T. G.; Khusnetdinova, K. A.

    2017-11-01

    The dynamics of population density and taxonomic structure of epiphytic bacterial communities on the leaves and roots of potatoes, carrots, and beets have been studied. Significant changes take place in the ontogenesis of these vegetables with substitution of hydrolytic bacteria for eccrisotrophic bacteria feeding on products of plant exosmosis. The frequency of domination of representatives of different taxa of epiphytic bacteria on the studied plants has been determined for the entire period of their growth. Bacteria of different genera have been isolated from the aboveground and underground organs of vegetables; their functions are discussed. It is shown that the taxonomic structure of bacterial communities in the soil under studied plants is not subjected to considerable changes and is characterized by the domination of typical soil bacteria— Arthrobacter and bacilli—with the appearance of Rhodococcus as a codominant at the end of the season (before harvesting).

  6. The presence of embedded bacterial pure cultures in agar plates stimulate the culturability of soil bacteria

    DEFF Research Database (Denmark)

    Burmølle, Mette; Johnsen, Kaare; Abu Al-Soud, Waleed Mohamad Abdel F

    2009-01-01

    Traditional methods for bacterial cultivation recover only a small fraction of bacteria from all sorts of natural environments, and attempts have been made to improve the bacterial culturability. Here we describe the development of a cultivation method, based on the embedment of pure bacterial...... cultures in between two layers of agar. Plates containing either embedded Pseudomonas putida or Arthrobacter globiformis resulted in higher numbers of CFUs of soil bacteria (21% and 38%, respectively) after 833 h of incubation, compared to plates with no embedded strain. This indicates a stimulatory effect...... of the bacterial pure cultures on the cultivation of soil bacteria. Analysis of partial 16S rRNA gene sequences revealed a phylogenetical distribution of the soil isolates into 7 classes in 4 phyla. No difference was observed at the phylum or class level when comparing isolates grouped according to embedded strain...

  7. A highly efficient transposon mutagenesis system for the tomato pathogen Clavibacter michiganensis subsp. michiganensis.

    Science.gov (United States)

    Kirchner, O; Gartemann, K H; Zellermann, E M; Eichenlaub, R; Burger, A

    2001-11-01

    A transposon mutagenesis system for Clavibacter michiganensis subsp. michiganensis was developed based on antibiotic resistance transposons that were derived from the insertion element IS1409 from Arthrobacter sp. strain TM1 NCIB12013. As a prerequisite, the electroporation efficiency was optimized by using unmethylated DNA and treatment of the cells with glycine such that about 5 x 10(6) transformants per microg of DNA were generally obtained. Electroporation of C. michiganensis subsp. michiganensis with a suicide vector carrying transposon Tn1409C resulted in approximately 1 x 10(3) transposon mutants per pg of DNA and thus is suitable for saturation mutagenesis. Analysis of Tn1409C insertion sites suggests a random mode of transposition. Transposition of Tn1409C was also demonstrated for other subspecies of C. michiganensis.

  8. Earthworms modify microbial community structure and accelerate maize stover decomposition during vermicomposting.

    Science.gov (United States)

    Chen, Yuxiang; Zhang, Yufen; Zhang, Quanguo; Xu, Lixin; Li, Ran; Luo, Xiaopei; Zhang, Xin; Tong, Jin

    2015-11-01

    In the present study, maize stover was vermicomposted with the epigeic earthworm Eisenia fetida. The results showed that, during vermicomposting process, the earthworms promoted decomposition of maize stover. Analysis of microbial communities of the vermicompost by high-throughput pyrosequencing showed more complex bacterial community structure in the substrate treated by the earthworms than that in the control group. The dominant microbial genera in the treatment with the earthworms were Pseudoxanthomonas, Pseudomonas, Arthrobacter, Streptomyces, Cryptococcus, Guehomyces, and Mucor. Compared to the control group, the relative abundance of lignocellulose degradation microorganisms increased. The results indicated that the earthworms modified the structure of microbial communities during vermicomposting process, activated the growth of lignocellulose degradation microorganisms, and triggered the lignocellulose decomposition.

  9. Exploring the diversity and antimicrobial potential of marine Actinobacteria from the Comau Fjord in Northern Patagonia, Chile

    Directory of Open Access Journals (Sweden)

    Agustina Undabarrena

    2016-07-01

    Full Text Available Bioprospecting natural products in marine bacteria from fjord environments are attractive due to their unique geographical features. Although Actinobacteria are well known for producing a myriad of bioactive compounds, investigations regarding fjord-derived marine Actinobacteria are scarce. In this study, the diversity and biotechnological potential of Actinobacteria isolated from marine sediments within the Comau fjord, in Northern Chilean Patagonia, were assessed by culture-based approaches. The 16S rRNA gene sequences revealed that members phylogenetically related to the Micrococcaceae, Dermabacteraceae, Brevibacteriaceae, Corynebacteriaceae, Microbacteriaceae, Dietziaceae, Nocardiaceae and Streptomycetaceae families were present at the Comau fjord. A high diversity of cultivable Actinobacteria (10 genera was retrieved by using only five different isolation media. Four isolates belonging to Arthrobacter, Brevibacterium, Corynebacterium and Kocuria genera showed 16S rRNA gene identity <98.7% suggesting that they are novel species. Physiological features such as salt tolerance, artificial sea water requirement, growth temperature, pigmentation and antimicrobial activity were evaluated. Arthrobacter, Brachybacterium, Curtobacterium, Rhodococcus and Streptomyces isolates showed strong inhibition against both Gram-negative Pseudomonas aeruginosa, Escherichia coli and Salmonella enterica and Gram-positive Staphylococcus aureus, Listeria monocytogenes. Antimicrobial activities in Brachybacterium, Curtobacterium and Rhodococcus have been scarcely reported, suggesting that non-mycelial strains are a suitable source of bioactive compounds. In addition, all strains bear at least one of the biosynthetic genes coding for NRPS (91%, PKS I (18% and PKS II (73%.Our results indicate that the Comau fjord is a promising source of novel Actinobacteria with biotechnological potential for producing biologically active compounds.

  10. Contribution of the microbial communities detected on an oil painting on canvas to its biodeterioration.

    Directory of Open Access Journals (Sweden)

    María Del Mar López-Miras

    Full Text Available In this study, we investigated the microbial community (bacteria and fungi colonising an oil painting on canvas, which showed visible signs of biodeterioration. A combined strategy, comprising culture-dependent and -independent techniques, was selected. The results derived from the two techniques were disparate. Most of the isolated bacterial strains belonged to related species of the phylum Firmicutes, as Bacillus sp. and Paenisporosarcina sp., whereas the majority of the non-cultivable members of the bacterial community were shown to be related to species of the phylum Proteobacteria, as Stenotrophomonas sp. Fungal communities also showed discrepancies: the isolated fungal strains belonged to different genera of the order Eurotiales, as Penicillium and Eurotium, and the non-cultivable belonged to species of the order Pleosporales and Saccharomycetales. The cultivable microorganisms, which exhibited enzymatic activities related to the deterioration processes, were selected to evaluate their biodeteriorative potential on canvas paintings; namely Arthrobacter sp. as the representative bacterium and Penicillium sp. as the representative fungus. With this aim, a sample taken from the painting studied in this work was examined to determine the stratigraphic sequence of its cross-section. From this information, "mock paintings," simulating the structure of the original painting, were prepared, inoculated with the selected bacterial and fungal strains, and subsequently examined by micro-Fourier Transform Infrared spectroscopy, in order to determine their potential susceptibility to microbial degradation. The FTIR-spectra revealed that neither Arthrobacter sp. nor Penicillium sp. alone, were able to induce chemical changes on the various materials used to prepare "mock paintings." Only when inoculated together, could a synergistic effect on the FTIR-spectra be observed, in the form of a variation in band position on the spectrum.

  11. Structural Variation in the Bacterial Community Associated with Airborne Particulate Matter in Beijing, China, during Hazy and Nonhazy Days.

    Science.gov (United States)

    Yan, Dong; Zhang, Tao; Su, Jing; Zhao, Li-Li; Wang, Hao; Fang, Xiao-Mei; Zhang, Yu-Qin; Liu, Hong-Yu; Yu, Li-Yan

    2018-05-01

    The structural variation of the bacterial community associated with particulate matter (PM) was assessed in an urban area of Beijing during hazy and nonhazy days. Sampling for different PM fractions (PM 2.5 [airborne bacterial community in these samples was analyzed using the Illumina MiSeq platform with bacterium-specific primers targeting the 16S rRNA gene. A total of 1,707,072 reads belonging to 6,009 operational taxonomic units were observed. The airborne bacterial community composition was significantly affected by PM fractions ( R = 0.157, P airborne bacterial community composition. Only six genera increased across PM 10 samples ( Dokdonella , Caenimonas , Geminicoccus , and Sphingopyxis ) and PM 2.5 samples ( Cellulomonas and Rhizobacter ), while a large number of taxa significantly increased in total suspended particulate samples, such as Paracoccus , Kocuria , and Sphingomonas Network analysis indicated that Paracoccus , Rubellimicrobium , Kocuria , and Arthrobacter were the key genera in the airborne PM samples. Overall, the findings presented here suggest that diverse airborne bacterial communities are associated with PM and provide further understanding of bacterial community structure in the atmosphere during hazy and nonhazy days. IMPORTANCE The results presented here represent an analysis of the airborne bacterial community associated with particulate matter (PM) and advance our understanding of the structural variation of these communities. We observed a shift in bacterial community composition with PM fractions but no significant difference with haze levels. This may be because the bacterial differences are obscured by high bacterial diversity in the atmosphere. However, we also observed that a few genera (such as Methylobacillus , Tumebacillus , and Desulfurispora ) increased significantly on heavy-haze days. In addition, Paracoccus , Rubellimicrobium , Kocuria , and Arthrobacter were the key genera in the airborne PM samples. Accurate and real

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

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    Luis M. Figueroa

    2017-11-01

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

  13. Potential application of metabolic engineering to tune the production of compatible solutes for enhancing tolerance of crop plants to salinity/drought (abstract)

    International Nuclear Information System (INIS)

    Sharmila, P.; Saradhi, P.P.

    2005-01-01

    Essential need to develop genotypes of crop plants that can substantially withstand salinity and drought with little yield losses is being increasingly felt, as the cultivable agricultural lands is increasingly being exposed to these stresses. In-spite of gains in productivity, conventional plant breeding methods have their limitations either due to limited gene pool or due to species barrier for gene transfer. Modern molecular tools have paved ways for identification of genes imparting abiotic stress tolerance in unrelated species/organisms and to transfer the selected genes into desirable crop plant species by conquering the incompatibility barriers. In fact, now genetic engineering has been widely realized to be in important tool for developing abiotic stress tolerant crop plants. Abiotic stress tolerance is a complex phenomenon involving simultaneous expression of a number of genes coupled with an interaction of varying weather variables and crop phonology. However, in order to tackle the issue, successful attempts have been made in identifying genes enhancing abiotic stress tolerance. The genes for biosynthesis of various compatible solutes (viz., mtlD for mannitol: P5CS or P5CSF129A for proline; coda/cox or belA/beIB for glycinebetaine' lpsl for trehalose; PINOI for inositol) have been demonstrated to enhance abiotic stress tolerance of plants. We have isolated the codA gene (Accession number AY589052) for choline oxidase from an Indian strain of Arthrobacter sp. from IMTECH (Chandigarh) and the mtlD genes from local strains of E. coli (accession number A Y523630) and halobacterium sp. (Accession number A Y52363 1). We have enhanced the tolerance of Brassica juncea to salt, drought and low temperature stresses by introducing the codA gene from Arthrobacter globiformis using Agrobacterium tumefaciens mediated transformation. Presenting our research team is busy developing genotypes of chickpea black gram, peanut and sorghum besides mustard with enhanced

  14. Correlation models between environmental factors and bacterial resistance to antimony and copper.

    Directory of Open Access Journals (Sweden)

    Zunji Shi

    Full Text Available Antimony (Sb and copper (Cu are toxic heavy metals that are associated with a wide variety of minerals. Sb(III-oxidizing bacteria that convert the toxic Sb(III to the less toxic Sb(V are potentially useful for environmental Sb bioremediation. A total of 125 culturable Sb(III/Cu(II-resistant bacteria from 11 different types of mining soils were isolated. Four strains identified as Arthrobacter, Acinetobacter and Janibacter exhibited notably high minimum inhibitory concentrations (MICs for Sb(III (>10 mM,making them the most highly Sb(III-resistant bacteria to date. Thirty-six strains were able to oxidize Sb(III, including Pseudomonas-, Comamonas-, Acinetobacter-, Sphingopyxis-, Paracoccus- Aminobacter-, Arthrobacter-, Bacillus-, Janibacter- and Variovorax-like isolates. Canonical correspondence analysis (CCA revealed that the soil concentrations of Sb and Cu were the most obvious environmental factors affecting the culturable bacterial population structures. Stepwise linear regression was used to create two predictive models for the correlation between soil characteristics and the bacterial Sb(III or Cu(II resistance. The concentrations of Sb and Cu in the soil was the significant factors affecting the bacterial Sb(III resistance, whereas the concentrations of S and P in the soil greatly affected the bacterial Cu(II resistance. The two stepwise linear regression models that we derived are as follows: MIC(Sb(III=606.605+0.14533 x C(Sb+0.4128 x C(Cu and MIC((Cu(II=58.3844+0.02119 x C(S+0.00199 x CP [where the MIC(Sb(III and MIC(Cu(II represent the average bacterial MIC for the metal of each soil (μM, and the C(Sb, C(Cu, C(S and C(P represent concentrations for Sb, Cu, S and P (mg/kg in soil, respectively, p<0.01]. The stepwise linear regression models we developed suggest that metals as well as other soil physicochemical parameters can contribute to bacterial resistance to metals.

  15. Promoting Uranium Immobilization by the Activities of Microbial Phosphatases

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, Robert J.; Beazley, Melanie J.; Wilson, Jarad J.; Taillefert, Martial; Sobecky, Patricia A.

    2005-04-05

    The overall goal of this project is to examine the role of nonspecific phosphohydrolases present in naturally occurring subsurface microorganisms for the purpose of promoting the immobilization of radionuclides through the production of uranium [U(VI)] phosphate precipitates. Specifically, we hypothesize that the precipitation of U(VI) phosphate minerals may be promoted through the microbial release and/or accumulation of PO{sub 4}{sup 3-}. During this phase of the project we have been conducting assays to determine the effects of pH, inorganic anions and organic ligands on U(VI) mineral formation and precipitation when FRC bacterial isolates were grown in simulated groundwater medium. The molecular characterization of FRC isolates has also been undertaken during this phase of the project. Analysis of a subset of gram-positive FRC isolates cultured from FRC soils (Areas 1, 2 and 3) and background sediments have indicated a higher percentage of isolates exhibiting phosphatase phenotypes (i.e., in particular those surmised to be PO{sub 4}{sup 3-}-irrepressible) relative to isolates from the reference site. A high percentage of strains that exhibited such putatively PO{sub 4}{sup 3-}-irrepressible phosphatase phenotypes were also resistant to the heavy metals lead and cadmium. Previous work on FRC strains, including Arthrobacter, Bacillus and Rahnella spp., has demonstrated differences in tolerance to U(VI) toxicity (200 {micro}M) in the absence of organophosphate substrates. For example, Arthrobacter spp. exhibited the greatest tolerance to U(VI) while the Rahnella spp. have been shown to facilitate the precipitation of U(VI) from solution and the Bacillus spp. demonstrate the greatest sensitivity to acidic conditions and high concentrations of U(VI). PCR-based detection of FRC strains are being conducted to determine if non-specific acid phosphatases of the known molecular classes [i.e., classes A, B and C] are present in these FRC isolates. Additionally, these

  16. Studies on the Catalytic Properties of Partially Purified Alkaline Proteases from Some Selected Microorganisms

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    Titilayo Olufunke Femi-Ola

    2012-09-01

    Full Text Available Aims: The research was done to study the conditions enhancing catalytic activities of alkaline proteases from Vibro sp., Lactobacillus brevis, Zymomonas sp., Athrobacter sp., Corynebacterium sp. and Bacillus subtilis.Methodology and Results: The proteolytic enzymes were purified in 2-step procedures involving ammonium sulphate precipitation and sephadex G-150 gel permeation chromatography. The upper and lower limits for the specific activities of proteases from the selected microorganisms were estimated at 20.63 and 47.51 units/mg protein with Zymomonas protease having the highest specific activity towards casein as its substrate and purification fold of 3.46, while that ofLactobacillus brevis protease was 8.06. The native molecular weights of these active proteins ranged from 30.4 to 45.7 kDa with Athrobacter sp. protease having the highest weight for its subunits. The proteolytic enzymes had optimum pH range of 8 to 10 and temperature range of 50 to 62 ºC accounting for the percentage relative activity range of 75 to 94% and 71 to 84 % respectively. The activities of Lactobacillus brevis and Bacillus subtilis proteases were maximum at pH 9 and 10 respectively. Lactobacillus brevis protease activity was maximum at temperature of 62 ºC, while beyond this value, a general thermal instability of these active proteins was observed. At above 70 ºC, the catalytic activities of Corynebacterium sp., Vibrio sp., Zymomonas sp. and Arthrobacter sp. proteases were progressively reduced over a period of 120 min of incubation, while Bacillus subtlis and Lactobacillus brevis proteases were relatively stable. Effect of metal ions was investigated on the catalytic activity of protease from the microorganisms. Lactobacillus brevis,Zymomonas sp., Arthrobacter sp., Corynebacterium sp. and Bacillus subtilis protease activities were strongly activated by metal ions such as Ca+2 and Mg+2. Enzyme activities were inhibited strongly by Cu2+ and Hg2+ but were not

  17. Dual isotope plots reflect transformation pathways of pesticides: Potential to assess pesticide fate and elucidate transformation mechanisms

    Science.gov (United States)

    Meyer, Armin; Penning, Holger; Sorensen, Sebastian; Aamand, Jens; Elsner, Martin

    2010-05-01

    The degradation of pesticides in deeper soil layers and groundwater is of growing interest, because they have repeatedly been found in drinking water supply wells and may pose a risk to future water resources. Current assessment schemes face a common problem, however: natural degradation often cannot be reliably assessed by concentration measurements alone, since mass balances are difficult to establish and transformation cannot be distinguished from sorption or dilution. Even detection of metabolites may only give an incomplete picture. When several transformation pathways occur, some metabolites may be degraded or form bound residues so that the associated pathways may be missed. Our research shows that dual isotope plots derived from compound specific isotope analysis offer a novel approach to give additional, complementary insight into the natural degradation of pesticides. Detection of metabolites is not required, since the isotope fractionation can be fully observed in the pesticide itself. Specifically, different initial biotransformation reactions of the phenylurea herbicide isoproturon (3-(4-isopropylphenyl)-1,1-dimethylurea) in pure culture experiments with bacterial and fungal strains showed strongly pathway-dependent isotope fractionation. When analyzing isotopic changes in different parts of the isoproturon molecule, hydroxylation of the isopropyl group by fungi was found to be associated with C and H isotope fractionation. In contrast, hydrolysis by Arthrobacter globiformis D47 caused strong C and N isotope fractionation, albeit in a different manner than abiotic hydrolysis so that isotope measurements can distinguish between both modes of transformation. Likewise, we observed highly pathway-dependent C and N isotope fractionation of atrazine (1-chloro-3-ethylamino-5-isopropylamino-2,4,6-triazine). Desalkylation of atrazine by Rhodococcus sp. strain NI86/21 resulted in enrichment of both 13-C and 15-N in atrazine, whereas hydrolysis to hydroxyatrazine

  18. Bacteria-Mineral Interactions on the Surfaces of Metal-Resistant Bacteria

    International Nuclear Information System (INIS)

    Malkin, A.J.

    2010-01-01

    The extraordinary ability of indigenous microorganisms, like metal-resistant bacteria, for biotransformation of toxic compounds is of considerable interest for the emerging area of environmental bioremediation. However, the underlying mechanisms by which metal-resistant bacteria transform toxic compounds are currently unknown and await elucidation. The project's objective was to study stress-induced responses of metal-resistant bacteria to environmental changes and chemical stimulants. This project involved a multi-institutional collaboration of our LLNL group with the group of Dr. H.-Y. Holman (Lawrence Berkeley National Laboratory). In this project, we have utilized metal-resistant bacteria Arthrobacter oxydans as a model bacterial system. We have utilized atomic force microscopy (AFM) to visualize for the first time at the nanometer scale formation of stress-induced structures on bacterial surfaces in response to Cr (VI) exposure. We have demonstrated that structure, assembly, and composition of these stress-induced structures are dependent on Cr (VI) concentrations. Our AFM observations of the appearance and development of stress-induced layers on the surfaces of Arthrobacter oxydans bacteria exposed to Cr (VI) were confirmed by Dr. Holman's biochemical, electron microscopy, and synchrotron infrared spectromicroscopy studies. In general, in vitro imaging of live microbial and cellular systems represents one of the most challenging issues in application of AFM. Various approaches for immobilization of bacteria on the substrate for in vitro imaging were tested in this project. Imaging of live bacteria was achieved, however further optimization of experimental methods are needed for high-resolution visualization of the cellular environmental structural dynamics by AFM. This project enhanced the current insight into molecular architecture, structural and environmental variability of bacterial systems. The project partially funded research for two book chapters (1

  19. Cultivation-Based and Molecular Assessment of Bacterial Diversity in the Rhizosheath of Wheat under Different Crop Rotations.

    Directory of Open Access Journals (Sweden)

    Muhammad Tahir

    Full Text Available A field study was conducted to compare the formationand bacterial communities of rhizosheaths of wheat grown under wheat-cotton and wheat-rice rotation and to study the effects of bacterial inoculation on plant growth. Inoculation of Azospirillum sp. WS-1 and Bacillus sp. T-34 to wheat plants increased root length, root and shoot dry weight and dry weight of rhizosheathsoil when compared to non-inoculated control plants, and under both crop rotations. Comparing both crop rotations, root length, root and shoot dry weight and dry weight of soil attached with roots were higher under wheat-cotton rotation. Organic acids (citric acid, malic acid, acetic acid and oxalic acid were detected in rhizosheaths from both rotations, with malic acid being most abundant with 24.8±2 and 21.3±1.5 μg g(-1 dry soil in wheat-cotton and wheat-rice rotation, respectively. Two sugars (sucrose, glucose were detected in wheat rhizosheath under both rotations, with highest concentrations of sucrose (4.08±0.5 μg g(-1 and 7.36±1.0 μg g(-1 and glucose (3.12±0.5 μg g(-1 and 3.01± μg g(-1 being detected in rhizosheaths of non-inoculated control plants under both rotations. Diversity of rhizosheath-associated bacteria was evaluated by cultivation, as well as by 454-pyrosequencing of PCR-tagged 16S rRNA gene amplicons. A total of 14 and 12 bacterial isolates predominantly belonging to the genera Arthrobacter, Azospirillum, Bacillus, Enterobacter and Pseudomonaswere obtained from the rhizosheath of wheat grown under wheat-cotton and wheat-rice rotation, respectively. Analysis of pyrosequencing data revealed Proteobacteria, Bacteriodetes and Verrucomicrobia as the most abundant phyla in wheat-rice rotation, whereas Actinobacteria, Firmicutes, Chloroflexi, Acidobacteria, Planctomycetes and Cyanobacteria were predominant in wheat-cotton rotation. From a total of 46,971 sequences, 10.9% showed ≥97% similarity with 16S rRNA genes of 32 genera previously shown to include

  20. Cell lysis and superoxide dismutase activities of highly radioresistant bacteria

    International Nuclear Information System (INIS)

    Yoshinaka, Taeko; Yano, Keiji; Yamaguchi, Hikoyuki

    1976-01-01

    The highly radioresistant bacterium, Arthrobacter radiotolerans, has been isolated from the radioactive hot spring of Misasa, and it does not sporulate, it is Gram-positive, and its color is pink to red. This bacterium shows the highest resistance to gamma-ray among Gram-positive resistants, but the lytic enzyme capable of lysing the cells of strong radioresistants and the surface structure of the cells are little known except those about Micrococcus radiodurans. The cells of the M. radiodurans can be lysed by Achramobacter lyticus enzyme, and electron microscopic observation and chemical analysis revealed the mutilayered surface structure of the cells consisting of an inner membrane, a mucopeptide wall layer and a very outer layer. The superoxide dismutase (SOD) activity of aerobic and anaerobic bacteria was studied, and the relatively high SOD activity of the M. radiodurans was found. The SOD function acts against the threat posed by the reactive superoxide radical being generated biologically, photochemically and radiochemically in the presence of molecular oxygen. In this paper, it is reported that the lytic enzyme No.2 obtained from Cytophaga sp., containing N-acetyl-muramyl-L-alanine amidase, peptidase and endopeptidase, and showing broad lytic spectra, was able to lyse the cells of A. radiotolerans and four radioresistant micrococci, and the radioresistant bacteria showed relatively high SOD activity except M. sp. 248. It is well known that superoxide anions are generated by aerobic irradiation, and are toxic to microbial cells. (Kako, I.)

  1. Bioaccumulation of uranium and thorium from the solution containing both elements using various microorganisms

    International Nuclear Information System (INIS)

    Tsuruta, T.

    2006-01-01

    The effects of proton, thorium and uranium on the bioaccumulation of thorium and uranium from the solution (pH 3.5) containing uranium and thorium using Streptomyces levoris cells were examined. The amount of thorium accumulated using the cells decreased by the pre-contact between the cells and the solution (pH 3.5) containing no metals, whereas that of uranium was almost unaffected by the treatment. The amount of thorium was almost unaffected by the existence of uranium. On the other hand, the amount of uranium accumulated was strongly affected by the thorium, especially thorium addition after uranium accumulation. The decrease of uranium accumulated by the addition of thorium after the accumulation of uranium was higher than that from the solution containing both elements. Therefore, the contribution of uranium-thorium exchange reaction was higher than that of competition reaction. Accordingly, proton-uranium-thorium exchange reaction was occurred in the accumulation of thorium from the solution containing thorium and uranium. The gram-positive bacteria, such as Micrococcus luteus, Arthrobacter nicotianae, Bacillus subtilis and B. megaterium, has a much higher separation factor as thorium/uranium than that of actinomycetes. These gram-positive bacterial strains can be used for the accumulation of thorium from the solution containing uranium and thorium

  2. Sterilization of peat by gamma radiation

    Energy Technology Data Exchange (ETDEWEB)

    Parker, F E; Vincent, J M [New South Wales Univ., Kensington (Australia). School of Microbiology

    1981-01-01

    The effect of gamma-radiation on the survival of microorganisms has been quantified for the natural population of two types of peat. Data for several microbial types have been separately determined by regular plating and by indirect statistical probability estimates including, a wholly enclosed 'inverted-bottle' technique for higher dose levels to exclude any possibility of post-treatment contamination. The most persistent microorganisms at intermediate dosage (2.5-3.5 Mrad) were commonly a micrococcus (which closely resembled Micrococcus radiodurans) arthrobacter-like rods, myxobacteria and amoeboid forms. The persistent organisms all survived because of high resistance to ..gamma..-irradiation, not because of high initial numbers. The most numerous true bacteria (including spore-formers), actinomycetes, filamentous fungi and yeasts were all readily destroyed. Although the safety margin with the commercially recommended dose of 5 Mrad is low for some of the more resistant organisms, no change is justified at this stage since the organisms most likely to survive such a dose do not seem to seriously affect the subsequent growth and survival of rhizobia. Moreover there would be some risk of radiation-induced peat toxicity if higher doses were applied and some post-irradiation contamination will be difficult to avoid in commercial production.

  3. Proposal for creation of a new genus Neomicrococcus gen. nov. to accommodate Zhihengliuella aestuarii Baik et al. 2011 and Micrococcus lactis Chittpurna et al. 2011 as Neomicrococcus aestuarii comb. nov. and Neomicrococcus lactis comb. nov.

    Science.gov (United States)

    Prakash, Om; Sharma, Avinash; Nimonkar, Yogesh; Shouche, Yogesh S

    2015-11-01

    Micrococcus lactis and Zhihengliuella aestuarii were described independently in 2011. Their type strains showed high levels of 16S rRNA gene sequence similarity (99.3%). Phylogenetic analysis revealed that M. lactis MCC 2278T and Z. aestuarii JCM 16166T formed a monophyletic group and showed distant relationships to other members of closely related genera such as Micrococcus, Zhihengliuella, Arthrobacter and Citricoccus. The presence of large proportions of iso-C14:0 and iso-C16:0 with small amounts of iso-C15:0 distinguished M. lactis MCC 2278T and Z. aestuarii JCM 16166T from other members of the genera Micrococcus and Zhihengliuella. Unlike other members of the genera Zhihengliuella and Micrococcus, M. lactis MCC 2278T and Z. aestuarii JCM 16166T showed growth at low concentrations of NaCl. Thus, based on distinctive phylogenetic, chemotaxonomic and physiological features of these two organisms in comparison with other members of the genera Micrococcus and Zhihengliuella, it is clear that they do not fit within the existing classification and deserve separate status. DNA-DNA hybridization between the two type strains was 63%, indicating that they represent separate species. In this study, we propose the creation of a novel genus, Neomicrococcus gen. nov., to accommodate the two species with Neomicrococcus aestuarii gen. nov., comb. nov. (type strain JCM 16166T = KCTC 19557T) as the type species. Neomicrococcus lactis comb. nov. (type strain MCC 2278T = DSM 23694T) is also proposed.

  4. Micrococcus lactis sp. nov., isolated from dairy industry waste.

    Science.gov (United States)

    Chittpurna; Singh, Pradip K; Verma, Dipti; Pinnaka, Anil Kumar; Mayilraj, Shanmugam; Korpole, Suresh

    2011-12-01

    A Gram-positive, yellow-pigmented, actinobacterial strain, DW152(T), was isolated from a dairy industry effluent treatment plant. 16S rRNA gene sequence analysis indicated that strain DW152(T) exhibited low similarity with many species with validly published names belonging to the genera Micrococcus and Arthrobacter. However, phenotypic properties including chemotaxonomic markers affiliated strain DW152(T) to the genus Micrococcus. Strain DW152(T) had ai-C(15:0) and i-C(15:0) as major cellular fatty acids, and MK-8(H(2)) as the major menaquinone. The cell-wall peptidoglycan of strain DW152(T) had l-lysine as the diagnostic amino acid and the type was A4α. The DNA G+C content of strain DW152(T) was 68.0 mol%. In 16S rRNA gene sequence analysis, strain DW152(T) exhibited significant similarity with Micrococcus terreus NBRC 104258(T), but the mean value of DNA-DNA relatedness between these strains was only 42.3%. Moreover, strain DW152(T) differed in biochemical and chemotaxonomic characteristics from M. terreus and other species of the genus Micrococcus. Based on the above differences, we conclude that strain DW152(T) should be treated as a novel species of the genus Micrococcus, for which the name Micrococcus lactis sp. nov. is proposed. The type strain of Micrococcus lactis sp. nov. is DW152(T) (=MTCC10523(T) =DSM 23694(T)).

  5. Cell lysis and superoxide dismutase activities of highly radioresistant bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Yoshinaka, T; Yano, K; Yamaguchi, H [Tokyo Univ. (Japan). Faculty of Agriculture

    1976-01-01

    The highly radioresistant bacterium, Arthrobacter radiotolerans, has been isolated from the radioactive hot spring of Misasa, and it does not sporulate, it is Gram-positive, and its color is pink to red. This bacterium shows the highest resistance to gamma-ray among Gram-positive resistants, but the lytic enzyme capable of lysing the cells of strong radioresistants and the surface structure of the cells are little known except those about Micrococcus radiodurans. The cells of the M. radiodurans can be lysed by Achramobacter lyticus enzyme, and electron microscopic observation and chemical analysis revealed the mutilayered surface structure of the cells consisting of an inner membrane, a mucopeptide wall layer and a very outer layer. The superoxide dismutase (SOD) activity of aerobic and anaerobic bacteria was studied, and the relatively high SOD activity of the M. radiodurans was found. The SOD function acts against the threat posed by the reactive superoxide radical being generated biologically, photochemically and radiochemically in the presence of molecular oxygen. In this paper, it is reported that the lytic enzyme No.2 obtained from Cytophaga sp., containing N-acetyl-muramyl-L-alanine amidase, peptidase and endopeptidase, and showing broad lytic spectra, was able to lyse the cells of A. radiotolerans and four radioresistant micrococci, and the radioresistant bacteria showedrelatively high SOD activity except M. sp. 248. It is well known that superoxide anions are generated by aerobic irradiation, and are toxic to microbial cells.

  6. Bioremediation Potential of Native Hydrocarbons Degrading Bacteria in Crude Oil Polluted Soil

    Directory of Open Access Journals (Sweden)

    Mariana MARINESCU

    2017-05-01

    Full Text Available Bioremediation of crude oil contaminated soil is an effective process to clean petroleum pollutants from the environment. Crude oil bioremediation of soils is limited by the bacteria activity in degrading the spills hydrocarbons. Native crude oil degrading bacteria were isolated from different crude oil polluted soils. The isolated bacteria belong to the genera Pseudomonas, Mycobacterium, Arthrobacter and Bacillus. A natural biodegradable product and bacterial inoculum were used for total petroleum hydrocarbon (TPH removal from an artificial polluted soil. For soil polluted with 5% crude oil, the bacterial top, including those placed in the soil by inoculation was 30 days after impact, respectively 7 days after inoculum application, while in soil polluted with 10% crude oil,  multiplication top of bacteria was observed in the determination made at 45 days after impact and 21 days after inoculum application, showing once again how necessary is for microorganisms habituation and adaptation to environment being a function of pollutant concentration. The microorganisms inoculated showed a slight adaptability in soil polluted with 5% crude oil, but complete inhibition in the first 30 days of experiment at 10% crude oil.

  7. Isolation and characterization of novel chitinolytic bacteria

    Science.gov (United States)

    Gürkök, Sümeyra; Görmez, Arzu

    2016-04-01

    Chitin, a linear polymer of β-1,4-N-acetylglucosamine units, is one of the most abundant biopolymers widely distributed in the marine and terrestrial environments. It is found as a structural component of insects, crustaceans and the cell walls of fungi. Chitinases, the enzymes degrading chitin by cleaving the β-(1-4) bond, have gained increased attention due to their wide range of biotechnological applications, especially for biocontrol of harmful insects and phytopathogenic fungi in agriculture. In the present study, 200 bacterial isolates from Western Anatolia Region of Turkey were screened for chitinolytic activity on agar media amended with colloidal chitin. Based on the chitin hydrolysis zone, 13 isolates were selected for further study. Bacterial isolates with the highest chitinase activity were identified as Acinetobacter calcoaceticus, Arthrobacter oxydans, Bacillus cereus, Bacillus megaterium, Brevibacillus reuszeri, Kocuria erythromyxa, Kocuria rosea, Novosphingobium capsulatum, Rhodococcus bratislaviensis, Rhodococcus fascians and Staphylococcus cohnii by MIS and BIOLOG systems. The next aims of the study are to compare the productivity of these bacteria quantitatively, to purify the enzyme from the most potent producer and to apply the pure enzyme for the fight against the phytopathogenic fungi and harmful insects.

  8. Investigation of bacterial transport in the large-block test, a thermally perturbed block of Topopah Spring tuff

    Energy Technology Data Exchange (ETDEWEB)

    Chen, C.I.; Meike, A.; Chuu, Y.J.; Sawvel, A.; Lin, W.

    1999-07-01

    Transport of bacteria is investigated as part of the Large-Block Test (LBT), a thermally perturbed block of Topopah Spring tuff. Two bacterial species, Bacillus subtilis and Arthrobacter oxydans, were isolated from the Yucca Mountain Tuff. Natural mutants that can grow under the simultaneous presence of the two antibiotics, streptomycin and rifampicin, were selected from these species by laboratory procedures, cultured, and injected into the five heater boreholes of the large block hours before heating was initiated. The temperature, as measured 5 cm above one of the heater boreholes, rose slowly over a matter of months to a maximum of 142 C and to 60 C at the top and bottom of the block. Samples were collected from boreholes located approximately 5 ft below the injection points. Double-drug-resistant microbes also appeared in the heater boreholes where the temperature had been sustainably high throughout the test. The number of double-drug-resistant bacteria that were identified in the collection boreholes increased with time until the heater was deactivated. Negative indications in the collection holes after the heater was deactivated support the supposition that these bacteria were the species that were injected. An apparent homogeneous distribution among the collection boreholes suggests no pattern to the migration of bacteria through the block. The relationship between bacterial migration and the movement of water is not yet understood. These observations indicate the possibility of rapid bacterial transport in a thermally perturbed geologic setting. The implications for colloid transport need to be reviewed.

  9. Investigation of bacterial transport in the large-block test, a thermally perturbed block of Topopah Spring tuff

    International Nuclear Information System (INIS)

    Chen, C.I.; Meike, A.; Chuu, Y.J.; Sawvel, A.; Lin, W.

    1999-01-01

    Transport of bacteria is investigated as part of the Large-Block Test (LBT), a thermally perturbed block of Topopah Spring tuff. Two bacterial species, Bacillus subtilis and Arthrobacter oxydans, were isolated from the Yucca Mountain Tuff. Natural mutants that can grow under the simultaneous presence of the two antibiotics, streptomycin and rifampicin, were selected from these species by laboratory procedures, cultured, and injected into the five heater boreholes of the large block hours before heating was initiated. The temperature, as measured 5 cm above one of the heater boreholes, rose slowly over a matter of months to a maximum of 142 C and to 60 C at the top and bottom of the block. Samples were collected from boreholes located approximately 5 ft below the injection points. Double-drug-resistant microbes also appeared in the heater boreholes where the temperature had been sustainably high throughout the test. The number of double-drug-resistant bacteria that were identified in the collection boreholes increased with time until the heater was deactivated. Negative indications in the collection holes after the heater was deactivated support the supposition that these bacteria were the species that were injected. An apparent homogeneous distribution among the collection boreholes suggests no pattern to the migration of bacteria through the block. The relationship between bacterial migration and the movement of water is not yet understood. These observations indicate the possibility of rapid bacterial transport in a thermally perturbed geologic setting. The implications for colloid transport need to be reviewed

  10. Detection and isolation of novel rhizopine-catabolizing bacteria from the environment

    Science.gov (United States)

    Gardener; de Bruijn FJ

    1998-12-01

    Microbial rhizopine-catabolizing (Moc) activity was detected in serial dilutions of soil and rhizosphere washes. The activity observed generally ranged between 10(6) and 10(7) catabolic units per g, and the numbers of nonspecific culture-forming units were found to be approximately 10 times higher. A diverse set of 37 isolates was obtained by enrichment on scyllo-inosamine-containing media. However, none of the bacteria that were isolated were found to contain DNA sequences homologous to the known mocA, mocB, and mocC genes of Sinorhizobium meliloti L5-30. Twenty-one of the isolates could utilize an SI preparation as the sole carbon and nitrogen source for growth. Partial sequencing of 16S ribosomal DNAs (rDNAs) amplified from these strains indicated that five distinct bacterial genera (Arthrobacter, Sinorhizobium, Pseudomonas, Aeromonas, and Alcaligenes) were represented in this set. Only 6 of these 21 isolates could catabolize 3-O-methyl-scyllo-inosamine under standard assay conditions. Two of these, strains D1 and R3, were found to have 16S rDNA sequences very similar to those of Sinorhizobium meliloti. However, these strains are not symbiotically effective on Medicago sativa, and DNA sequences homologous to the nodB and nodC genes were not detected in strains D1 and R3 by Southern hybridization analysis.

  11. High-throughput DNA microarray detection of pathogenic bacteria in shallow well groundwater in the Kathmandu Valley, Nepal.

    Science.gov (United States)

    Inoue, Daisuke; Hinoura, Takuji; Suzuki, Noriko; Pang, Junqin; Malla, Rabin; Shrestha, Sadhana; Chapagain, Saroj Kumar; Matsuzawa, Hiroaki; Nakamura, Takashi; Tanaka, Yasuhiro; Ike, Michihiko; Nishida, Kei; Sei, Kazunari

    2015-01-01

    Because of heavy dependence on groundwater for drinking water and other domestic use, microbial contamination of groundwater is a serious problem in the Kathmandu Valley, Nepal. This study investigated comprehensively the occurrence of pathogenic bacteria in shallow well groundwater in the Kathmandu Valley by applying DNA microarray analysis targeting 941 pathogenic bacterial species/groups. Water quality measurements found significant coliform (fecal) contamination in 10 of the 11 investigated groundwater samples and significant nitrogen contamination in some samples. The results of DNA microarray analysis revealed the presence of 1-37 pathogen species/groups, including 1-27 biosafety level 2 ones, in 9 of the 11 groundwater samples. While the detected pathogens included several feces- and animal-related ones, those belonging to Legionella and Arthrobacter, which were considered not to be directly associated with feces, were detected prevalently. This study could provide a rough picture of overall pathogenic bacterial contamination in the Kathmandu Valley, and demonstrated the usefulness of DNA microarray analysis as a comprehensive screening tool of a wide variety of pathogenic bacteria.

  12. Radiation disinfection of rice-straw products

    International Nuclear Information System (INIS)

    Ito, Hitoshi; Ishigaki, Isao; Ohki, Yumi.

    1991-01-01

    For the quarantine treatment of rice-straw products from foreign countries, irradiation effects of gamma-rays and electron beams on plant pathogenic microorganisms especially on fungi were investigated. The total aerobic bacteria in rice-straw was determined to be 3x10 7 - 3x10 8 per gram which consisted mainly of Pseudomonas, Flavobacterium, Arthrobacter and Erwinia. The principal bacteria in rice-straw could be eliminated with 5 kGy of gamma irradiation. Deinococcus proteolyticus and Pseudomonas radiora were the main survivors at 5 to 12 kGy of irradiation. Saprophytic fungus which belongs to Dimorphospora also survived up to 8 kGy of irradiation. The D 10 values of 26 strains of fungi isolated from rice-straw were 1.1 to 2.5 times higher in the dry condition compared to the values when irradiated in 0.067 M phosphate buffer solution. The induction dose in the dry condition also increased from 1.5 to 10 times than that in the wet condition. In the case of electron beam irradiation of fungi under dry conditions, D 10 values were about 1.3 times higher than that of gamma irradiation. From this study, the dose necessary to reduce the plant pathogenic fungi in rice-straw at a level below 10 -4 per gram was estimated to be as 7-8 kGy for gamma-irradiation and 10 kGy for electron beam irradiation. (author)

  13. Chemical Modification and Detoxification of the Pseudomonas aeruginosa Toxin 2-Heptyl-4-hydroxyquinoline N-Oxide by Environmental and Pathogenic Bacteria.

    Science.gov (United States)

    Thierbach, Sven; Birmes, Franziska S; Letzel, Matthias C; Hennecke, Ulrich; Fetzner, Susanne

    2017-09-15

    2-Heptyl-4-hydroxyquinoline N-oxide (HQNO), a major secondary metabolite and virulence factor produced by the opportunistic pathogen Pseudomonas aeruginosa, acts as a potent inhibitor of respiratory electron transfer and thereby affects host cells as well as microorganisms. In this study, we demonstrate the previously unknown capability of environmental and pathogenic bacteria to transform and detoxify this compound. Strains of Arthrobacter and Rhodococcus spp. as well as Staphylococcus aureus introduced a hydroxyl group at C-3 of HQNO, whereas Mycobacterium abscessus, M. fortuitum, and M. smegmatis performed an O-methylation, forming 2-heptyl-1-methoxy-4-oxoquinoline as the initial metabolite. Bacillus spp. produced the glycosylated derivative 2-heptyl-1-(β-d-glucopyranosydyl)-4-oxoquinoline. Assaying the effects of these metabolites on cellular respiration and on quinol oxidase activity of membrane fractions revealed that their EC 50 values were up to 2 orders of magnitude higher than that of HQNO. Furthermore, cellular levels of reactive oxygen species were significantly lower in the presence of the metabolites than under the influence of HQNO. Therefore, the capacity to transform HQNO should lead to a competitive advantage against P. aeruginosa. Our findings contribute new insight into the metabolic diversity of bacteria and add another layer of complexity to the metabolic interactions which likely contribute to shaping polymicrobial communities comprising P. aeruginosa.

  14. Volatile compounds from beneficial or pathogenic bacteria differentially regulate root exudation, transcription of iron transporters, and defense signaling pathways in Sorghum bicolor.

    Science.gov (United States)

    Hernández-Calderón, Erasto; Aviles-Garcia, Maria Elizabeth; Castulo-Rubio, Diana Yazmín; Macías-Rodríguez, Lourdes; Ramírez, Vicente Montejano; Santoyo, Gustavo; López-Bucio, José; Valencia-Cantero, Eduardo

    2018-02-01

    Our results show that Sorghum bicolor is able to recognize bacteria through its volatile compounds and differentially respond to beneficial or pathogens via eliciting nutritional or defense adaptive traits. Plants establish beneficial, harmful, or neutral relationships with bacteria. Plant growth promoting rhizobacteria (PGPR) emit volatile compounds (VCs), which may act as molecular cues influencing plant development, nutrition, and/or defense. In this study, we compared the effects of VCs produced by bacteria with different lifestyles, including Arthrobacter agilis UMCV2, Bacillus methylotrophicus M4-96, Sinorhizobium meliloti 1021, the plant pathogen Pseudomonas aeruginosa PAO1, and the commensal rhizobacterium Bacillus sp. L2-64, on S. bicolor. We show that VCs from all tested bacteria, except Bacillus sp. L2-64, increased biomass and chlorophyll content, and improved root architecture, but notheworthy A. agilis induced the release of attractant molecules, whereas P. aeruginosa activated the exudation of growth inhibitory compounds by roots. An analysis of the expression of iron-transporters SbIRT1, SbIRT2, SbYS1, and SbYS2 and genes related to plant defense pathways COI1 and PR-1 indicated that beneficial, pathogenic, and commensal bacteria could up-regulate iron transporters, whereas only beneficial and pathogenic species could induce a defense response. These results show how S. bicolor could recognize bacteria through their volatiles profiles and highlight that PGPR or pathogens can elicit nutritional or defensive traits in plants.

  15. A new technique for promoting cyclic utilization of cyclodextrins in biotransformation.

    Science.gov (United States)

    Shen, Yanbing; Yu, Ziqi; Yang, Xu; Wang, Fang; Luo, Jianmei; Wang, Min

    2017-01-01

    Cyclodextrins (CDs) can improve the productivity of steroid biotransformation by enhancing substrate solubility. CDs can be recycled by grafting them with appropriate carriers. Loofah fiber is an excellent grafting material for CDs, and can be applied to the biotransformation and recycling of β-cyclodextrin (β-CD). In this work, a technique for recycling β-CD in cortisone acetate (CA) biotransformation by Arthrobacter simplex CPCC 140451 was studied. Loofah fiber-grafted β-CD (LF-β-CD) was prepared using epichlorohydrin, which is a cross-linking agent. The grafting yield of β-CD was 74.8 mg g -1 dried fibers. LF-β-CD could increase the solubility of CA and enhance biotransformation. The initial conversion rate of CA was 1.5-fold higher than that of the blank group. LF-β-CD was also used in biocatalytic reactions for eight cycles, and it maintained the conversion ratio of CA at approximately 90%. Given the above positive results, LF-β-CD can be utilized in biotechnological recycling applications. This method can also be applied to CD derivatives and hydrophobic compounds.

  16. Isolation and characterization of mesotrione-degrading Bacillus sp. from soil

    International Nuclear Information System (INIS)

    Batisson, Isabelle; Crouzet, Olivier; Besse-Hoggan, Pascale; Sancelme, Martine; Mangot, Jean-Francois; Mallet, Clarisse; Bohatier, Jacques

    2009-01-01

    Dissipation kinetics of mesotrione, a new triketone herbicide, sprayed on soil from Limagne (Puy-de-Dome, France) showed that the soil microflora were able to biotransform it. Bacteria from this soil were cultured in mineral salt solution supplemented with mesotrione as sole source of carbon for the isolation of mesotrione-degrading bacteria. The bacterial community structure of the enrichment cultures was analyzed by temporal temperature gradient gel electrophoresis (TTGE). The TTGE fingerprints revealed that mesotrione had an impact on bacterial community structure only at its highest concentrations and showed mesotrione-sensitive and mesotrione-adapted strains. Two adapted strains, identified as Bacillus sp. and Arthrobacter sp., were isolated by colony hybridization methods. Biodegradation assays showed that only the Bacillus sp. strain was able to completely and rapidly biotransform mesotrione. Among several metabolites formed, 2-amino-4-methylsulfonylbenzoic acid (AMBA) accumulated in the medium. Although sulcotrione has a chemical structure closely resembling that of mesotrione, the isolates were unable to degrade it. - A Bacillus sp. strain isolated from soil was able to completely and rapidly biotransform the triketone herbicide mesotrione

  17. Physiological and biochemical characterization of a novel nicotine-degrading bacterium Pseudomonas geniculata N1.

    Directory of Open Access Journals (Sweden)

    Yanghui Liu

    Full Text Available Management of solid wastes with high nicotine content, such as those accumulated during tobacco manufacturing, poses a major challenge, which can be addressed by using bacteria such as Pseudomonas and Arthrobacter. In this study, a new species of Pseudomonas geniculata, namely strain N1, which is capable of efficiently degrading nicotine, was isolated and identified. The optimal growth conditions for strain N1 are a temperature of 30°C, and a pH 6.5, at a rotation rate of 120 rpm min(-1 with 1 g l(-1 nicotine as the sole source of carbon and nitrogen. Myosmine, cotinine, 6-hydroxynicotine, 6-hydroxy-N-methylmyosmine, and 6-hydroxy-pseudooxynicotine were detected as the five intermediates through gas chromatography-mass and liquid chromatography-mass analyses. The identified metabolites were different from those generated by Pseudomonas putida strains. The analysis also highlighted the bacterial metabolic diversity in relation to nicotine degradation by different Pseudomonas strains.

  18. Zinc bioaccumulation by microbial consortium isolated from nickel smelter sludge disposal site

    Directory of Open Access Journals (Sweden)

    Kvasnová Simona

    2017-06-01

    Full Text Available Heavy metal pollution is one of the most important environmental issues of today. Bioremediation by microorganisms is one of technologies extensively used for pollution treatment. In this study, we investigated the heavy metal resistance and zinc bioaccumulation by microbial consortium isolated from nickel sludge disposal site near Sereď (Slovakia. The composition of consortium was analyzed based on MALDI-TOF MS of cultivable bacteria and we have shown that the consortium was dominated by bacteria of genus Arthrobacter. While consortium showed very good growth in the zinc presence, it was able to remove only 15 % of zinc from liquid media. Selected members of consortia have shown lower growth rates in the zinc presence but selected isolates have shown much higher bioaccumulation abilities compared to whole consortium (up to 90 % of zinc removal for NH1 strain. Bioremediation is frequently accelerated through injection of native microbiota into a contaminated area. Based on data obtained in this study, we can conclude that careful selection of native microbiota could lead to the identification of bacteria with increased bioaccumulation abilities.

  19. Crude oil treatment leads to shift of bacterial communities in soils from the deep active layer and upper permafrost along the China-Russia Crude Oil Pipeline route.

    Science.gov (United States)

    Yang, Sizhong; Wen, Xi; Zhao, Liang; Shi, Yulan; Jin, Huijun

    2014-01-01

    The buried China-Russia Crude Oil Pipeline (CRCOP) across the permafrost-associated cold ecosystem in northeastern China carries a risk of contamination to the deep active layers and upper permafrost in case of accidental rupture of the embedded pipeline or migration of oil spills. As many soil microbes are capable of degrading petroleum, knowledge about the intrinsic degraders and the microbial dynamics in the deep subsurface could extend our understanding of the application of in-situ bioremediation. In this study, an experiment was conducted to investigate the bacterial communities in response to simulated contamination to deep soil samples by using 454 pyrosequencing amplicons. The result showed that bacterial diversity was reduced after 8-weeks contamination. A shift in bacterial community composition was apparent in crude oil-amended soils with Proteobacteria (esp. α-subdivision) being the dominant phylum, together with Actinobacteria and Firmicutes. The contamination led to enrichment of indigenous bacterial taxa like Novosphingobium, Sphingobium, Caulobacter, Phenylobacterium, Alicylobacillus and Arthrobacter, which are generally capable of degrading polycyclic aromatic hydrocarbons (PAHs). The community shift highlighted the resilience of PAH degraders and their potential for in-situ degradation of crude oil under favorable conditions in the deep soils.

  20. Crude oil treatment leads to shift of bacterial communities in soils from the deep active layer and upper permafrost along the China-Russia Crude Oil Pipeline route.

    Directory of Open Access Journals (Sweden)

    Sizhong Yang

    Full Text Available The buried China-Russia Crude Oil Pipeline (CRCOP across the permafrost-associated cold ecosystem in northeastern China carries a risk of contamination to the deep active layers and upper permafrost in case of accidental rupture of the embedded pipeline or migration of oil spills. As many soil microbes are capable of degrading petroleum, knowledge about the intrinsic degraders and the microbial dynamics in the deep subsurface could extend our understanding of the application of in-situ bioremediation. In this study, an experiment was conducted to investigate the bacterial communities in response to simulated contamination to deep soil samples by using 454 pyrosequencing amplicons. The result showed that bacterial diversity was reduced after 8-weeks contamination. A shift in bacterial community composition was apparent in crude oil-amended soils with Proteobacteria (esp. α-subdivision being the dominant phylum, together with Actinobacteria and Firmicutes. The contamination led to enrichment of indigenous bacterial taxa like Novosphingobium, Sphingobium, Caulobacter, Phenylobacterium, Alicylobacillus and Arthrobacter, which are generally capable of degrading polycyclic aromatic hydrocarbons (PAHs. The community shift highlighted the resilience of PAH degraders and their potential for in-situ degradation of crude oil under favorable conditions in the deep soils.

  1. Bacterial communities in ancient permafrost profiles of Svalbard, Arctic.

    Science.gov (United States)

    Singh, Purnima; Singh, Shiv M; Singh, Ram N; Naik, Simantini; Roy, Utpal; Srivastava, Alok; Bölter, Manfred

    2017-12-01

    Permafrost soils are unique habitats in polar environment and are of great ecological relevance. The present study focuses on the characterization of bacterial communities from permafrost profiles of Svalbard, Arctic. Counts of culturable bacteria range from 1.50 × 10 3 to 2.22 × 10 5 CFU g -1 , total bacterial numbers range from 1.14 × 10 5 to 5.52 × 10 5 cells g -1 soil. Bacterial isolates are identified through 16S rRNA gene sequencing. Arthrobacter and Pseudomonas are the most dominant genera, and A. sulfonivorans, A. bergeri, P. mandelii, and P. jessenii as the dominant species. Other species belong to genera Acinetobacter, Bacillus, Enterobacter, Nesterenkonia, Psychrobacter, Rhizobium, Rhodococcus, Sphingobacterium, Sphingopyxis, Stenotrophomonas, and Virgibacillus. To the best of our knowledge, genera Acinetobacter, Enterobacter, Nesterenkonia, Psychrobacter, Rhizobium, Sphingobacterium, Sphingopyxis, Stenotrophomonas, and Virgibacillus are the first northernmost records from Arctic permafrost. The present study fills the knowledge gap of culturable bacterial communities and their chronological characterization from permafrost soils of Ny-Ålesund (79°N), Arctic. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Effect of immobilization of a bacterial consortium on diuron dissipation and community dynamics.

    Science.gov (United States)

    Bazot, Stéphane; Lebeau, Thierry

    2009-09-01

    This work intended to study the relationship between diuron herbicide dissipation and the population dynamics of co-cultivated Delftia acidovorans WDL34 (WDL34) and Arthrobacter sp. N4 (N4) for different cell formulations: free cells or immobilization in Ca-alginate beads of one or both strains. GFP-tagged WDL34 and N4 Gram staining allowed analyzing the cell growth and distribution of each strain in both beads and culture medium in the course of the time. Compared to the free cell co-culture of WDL34 and N4, immobilization of WDL34 in Ca-alginate beads co-cultivated with free N4 increased the dissipation rate of diuron by 53% (0.141 mg ml(-1) h(-1)). In that case, immobilization strongly modified the final equilibrium among both strains (highest total N4 to WDL34 ratio). Our results demonstrated that the inoculant formulation played a major role in the cell growth of each cultivated strain possibly increasing diuron dissipation. This optimized cell formulation may allow improving water and soil treatment.

  3. Quality assessment of digested sludges produced by advanced stabilization processes.

    Science.gov (United States)

    Braguglia, C M; Coors, A; Gallipoli, A; Gianico, A; Guillon, E; Kunkel, U; Mascolo, G; Richter, E; Ternes, T A; Tomei, M C; Mininni, G

    2015-05-01

    The European Union (EU) Project Routes aimed to discover new routes in sludge stabilization treatments leading to high-quality digested sludge, suitable for land application. In order to investigate the impact of different enhanced sludge stabilization processes such as (a) thermophilic digestion integrated with thermal hydrolysis pretreatment (TT), (b) sonication before mesophilic/thermophilic digestion (UMT), and (c) sequential anaerobic/aerobic digestion (AA) on digested sludge quality, a broad class of conventional and emerging organic micropollutants as well as ecotoxicity was analyzed, extending the assessment beyond the parameters typically considered (i.e., stability index and heavy metals). The stability index was improved by adding aerobic posttreatment or by operating dual-stage process but not by pretreatment integration. Filterability was worsened by thermophilic digestion, either alone (TT) or coupled with mesophilic digestion (UMT). The concentrations of heavy metals, present in ranking order Zn > Cu > Pb > Cr ~ Ni > Cd > Hg, were always below the current legal requirements for use on land and were not removed during the processes. Removals of conventional and emerging organic pollutants were greatly enhanced by performing double-stage digestion (UMT and AA treatment) compared to a single-stage process as TT; the same trend was found as regards toxicity reduction. Overall, all the digested sludges exhibited toxicity to the soil bacterium Arthrobacter globiformis at concentrations about factor 100 higher than the usual application rate of sludge to soil in Europe. For earthworms, a safety margin of factor 30 was generally achieved for all the digested samples.

  4. High-throughput sequencing of microbial community diversity in soil, grapes, leaves, grape juice and wine of grapevine from China.

    Science.gov (United States)

    Wei, Yu-Jie; Wu, Yun; Yan, Yin-Zhuo; Zou, Wan; Xue, Jie; Ma, Wen-Rui; Wang, Wei; Tian, Ge; Wang, Li-Ye

    2018-01-01

    In this study Illumina MiSeq was performed to investigate microbial diversity in soil, leaves, grape, grape juice and wine. A total of 1,043,102 fungal Internal Transcribed Spacer (ITS) reads and 2,422,188 high quality bacterial 16S rDNA sequences were used for taxonomic classification, revealed five fungal and eight bacterial phyla. At the genus level, the dominant fungi were Ascomycota, Sordariales, Tetracladium and Geomyces in soil, Aureobasidium and Pleosporaceae in grapes leaves, Aureobasidium in grape and grape juice. The dominant bacteria were Kaistobacter, Arthrobacter, Skermanella and Sphingomonas in soil, Pseudomonas, Acinetobacter and Kaistobacter in grape and grapes leaves, and Oenococcus in grape juice and wine. Principal coordinate analysis showed structural separation between the composition of fungi and bacteria in all samples. This is the first study to understand microbiome population in soil, grape, grapes leaves, grape juice and wine in Xinjiang through High-throughput Sequencing and identify microorganisms like Saccharomyces cerevisiae and Oenococcus spp. that may contribute to the quality and flavor of wine.

  5. Microbial ecology of bacterially mediated PCB biodegradation

    International Nuclear Information System (INIS)

    Pettigrew, C.A. Jr.

    1989-01-01

    The roles of plasmid mediated and consortia mediated polychlorinated biphenyl (PCB) biodegradation by bacterial populations isolated from PCB contaminated freshwater sediments were investigated. PCB degrading bacteria were isolated by DNA:DNA colony hybridization, batch enrichments, and chemostat enrichment. Analysis of substrate removal and metabolite production were done using chlorinated biphenyl spray plates, reverse phase high pressure liquid chromatography, Cl - detection, and 14 C-labeled substrate mineralization methods. A bacterial consortium, designated LPS10, involved in a concerted metabolic attack on chlorinated biphenyls, was shown to mineralize 4-chlorobiphenyl (4CB) and 4,4'-dichlorobiphenyl (4,4' CB). The LPS10 consortium was isolated by both batch and chemostat enrichment using 4CB and biphenyl (BP) as sole carbon source and was found to have tree bacterial isolates that predominated; these included: Pseudomonas, testosteroni LPS10A which mediated the breakdown of 4CB and 4,4' CB to the putative meta-cleavage product and subsequently to 4-chlorobenzoic acid (4CBA), an isolate tentatively identified as an Arthrobacter sp. LPS10B which mediated 4CBA degradation, and Pseudomonas putida by A LPS10C whose role in the consortium has not been determined

  6. Genetic diversity of culturable bacteria in oil-contaminated rhizosphere of Galega orientalis

    International Nuclear Information System (INIS)

    Jussila, Minna M.; Jurgens, German; Lindstroem, Kristina; Suominen, Leena

    2006-01-01

    A collection of 50 indigenous meta-toluate tolerating bacteria isolated from oil-contaminated rhizosphere of Galega orientalis on selective medium was characterized and identified by classical and molecular methods. 16S rDNA partial sequencing showed the presence of five major lineages of the Bacteria domain. Gram-positive Rhodococcus, Bacillus and Arthrobacter and gram-negative Pseudomonas were the most abundant genera. Only one-fifth of the strains that tolerated m-toluate also degraded m-toluate. The inoculum Pseudomonas putida PaW85 was not found in the rhizosphere samples. The ability to degrade m-toluate by the TOL plasmid was detected only in species of the genus Pseudomonas. However, a few Rhodococcus erythropolis strains were found which were able to degrade m-toluate. A new finding was that Pseudomonas migulae strains and a few P. oryzihabitans strains were able to grow on m-toluate and most likely contained the TOL plasmid. Because strain specific differences in degradation abilities were found for P. oryzihabitans, separation at the strain level was important. For strain specific separation (GTG) 5 fingerprinting was the best method. A combination of the single locus ribotyping and the whole genomic fingerprinting techniques with the selective partial sequencing formed a practical molecular toolbox for studying genetic diversity of culturable bacteria in oil-contaminated rhizosphere. - Bacterial diversity during rhizoremediation in oil-contaminated soil is characterized by a combination of molecular methods

  7. Removal of Cr(VI) from aqueous solutions by a bacterial biofilm supported on zeolite: optimisation of the operational conditions and Scale-Up of the bioreactor

    Energy Technology Data Exchange (ETDEWEB)

    Pazos, M. [IBB - Instituto de Biotecnologia e Bioengenharia, Centro de Engenharia Biologica, Universidade do Minho, Braga (Portugal); Departamento de Ingenieria Quimica, Universidade de Vigo, Vigo (Spain); Branco, M.; Tavares, T. [IBB - Instituto de Biotecnologia e Bioengenharia, Centro de Engenharia Biologica, Universidade do Minho, Braga (Portugal); Neves, I.C. [Departamento de Quimica, Centro de Quimica, Universidade do Minho, Braga (Portugal); Sanroman, M.A. [Departamento de Ingenieria Quimica, Universidade de Vigo, Vigo (Spain)

    2010-12-15

    The aim of this study was to investigate the feasibility of a bioreactor system and its scale-up to remove Cr(VI) from solution. The bioreactor is based on an innovative process that combines bioreduction of Cr(VI) to Cr(III) by the bacterium Arthrobacter viscosus and Cr(III) sorption by a specific zeolite. Batch studies were conducted in a laboratory-scale bioreactor, taking into account different operating conditions. Several variables, such as biomass concentration, pH and zeolite pre-treatment, were evaluated to increase removal efficiency. The obtained results suggest that the Cr removal efficiency is improved when the initial biomass concentration is approximately 5 g L{sup -1} and the pH in the system is maintained at an acidic level. Under the optimised conditions, approximately 100 % of the Cr(VI) was removed. The scale-up of the developed biofilm process operating under the optimised conditions was satisfactorily tested in a 150-L bioreactor. (Copyright copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  8. Effect of Shadowing on Survival of Bacteria under Conditions Simulating the Martian Atmosphere and UV Radiation▿ †

    Science.gov (United States)

    Osman, Shariff; Peeters, Zan; La Duc, Myron T.; Mancinelli, Rocco; Ehrenfreund, Pascale; Venkateswaran, Kasthuri

    2008-01-01

    Spacecraft-associated spores and four non-spore-forming bacterial isolates were prepared in Atacama Desert soil suspensions and tested both in solution and in a desiccated state to elucidate the shadowing effect of soil particulates on bacterial survival under simulated Martian atmospheric and UV irradiation conditions. All non-spore-forming cells that were prepared in nutrient-depleted, 0.2-μm-filtered desert soil (DSE) microcosms and desiccated for 75 days on aluminum died, whereas cells prepared similarly in 60-μm-filtered desert soil (DS) microcosms survived such conditions. Among the bacterial cells tested, Microbacterium schleiferi and Arthrobacter sp. exhibited elevated resistance to 254-nm UV irradiation (low-pressure Hg lamp), and their survival indices were comparable to those of DS- and DSE-associated Bacillus pumilus spores. Desiccated DSE-associated spores survived exposure to full Martian UV irradiation (200 to 400 nm) for 5 min and were only slightly affected by Martian atmospheric conditions in the absence of UV irradiation. Although prolonged UV irradiation (5 min to 12 h) killed substantial portions of the spores in DSE microcosms (∼5- to 6-log reduction with Martian UV irradiation), dramatic survival of spores was apparent in DS-spore microcosms. The survival of soil-associated wild-type spores under Martian conditions could have repercussions for forward contamination of extraterrestrial environments, especially Mars. PMID:18083857

  9. Microbial degradation of Cold Lake Blend and Western Canadian select dilbits by freshwater enrichments.

    Science.gov (United States)

    Deshpande, Ruta S; Sundaravadivelu, Devi; Techtmann, Stephen; Conmy, Robyn N; Santo Domingo, Jorge W; Campo, Pablo

    2018-06-15

    Treatability experiments were conducted to determine the biodegradation of diluted bitumen (dilbit) at 5 and 25 °C for 72 and 60 days, respectively. Microbial consortia obtained from the Kalamazoo River Enbridge Energy spill site were enriched on dilbit at both 5 (cryo) and 25 (meso) ºC. On every sampling day, triplicates were sacrificed and residual hydrocarbon concentrations (alkanes and polycyclic aromatic hydrocarbons) were determined by GCMS/MS. The composition and relative abundance of different bacterial groups were identified by 16S rRNA gene sequencing analysis. While some physicochemical differences were observed between the two dilbits, their biodegradation profiles were similar. The rates and extent of degradation were greater at 25 °C. Both consortia metabolized 99.9% of alkanes; however, the meso consortium was more effective at removing aromatics than the cryo consortium (97.5 vs 70%). Known hydrocarbon-degrading bacteria were present in both consortia (Pseudomonas, Rhodococcus, Hydrogenophaga, Parvibaculum, Arthrobacter, Acidovorax), although their relative abundances depended on the temperatures at which they were enriched. Regardless of the dilbit type, the microbial community structure significantly changed as a response to the diminishing hydrocarbon load. Our results demonstrate that dilbit can be effectively degraded by autochthonous microbial consortia from sites with recent exposure to dilbit contamination. Published by Elsevier B.V.

  10. Diversity, ecological distribution and biotechnological potential of Actinobacteria inhabiting seamounts and non-seamounts in the Tyrrhenian Sea

    KAUST Repository

    Ettoumi, Besma; Chouchane, Habib; Guesmi, Amel; Mahjoubi, Mouna; Brusetti, Lorenzo; Neifar, Mohamed; Borin, Sara; Daffonchio, Daniele; Cherif, Ameur

    2016-01-01

    In the present study, the ecological distribution of marine Actinobacteria isolated from seamount and non-seamount stations in the Tyrrhenian Sea was investigated. A collection of 110 isolates was analyzed by Automated Ribosomal Intergenic Spacer Analysis (ARISA) and 16S rRNA gene sequencing of representatives for each ARISA haplotype (n = 49). Phylogenetic analysis of 16S rRNA sequences showed a wide diversity of marine isolates and clustered the strains into 11 different genera, Janibacter, Rhodococcus, Arthrobacter, Kocuria, Dietzia, Curtobacterium, Micrococcus, Citricoccus, Brevibacterium, Brachybacterium and Nocardioides. Interestingly, Janibacter limosus was the most encountered species particularly in seamounts stations, suggesting that it represents an endemic species of this particular ecosystem. The application of BOX-PCR fingerprinting on J. limosus sub-collection (n = 22), allowed their separation into seven distinct BOX-genotypes suggesting a high intraspecific microdiversity among the collection. Furthermore, by screening the biotechnological potential of selected actinobacterial strains, J. limosus was shown to exhibit the most important biosurfactant activity. Our overall data indicates that Janibacter is a major and active component of seamounts in the Tyrrhenian Sea adapted to low nutrient ecological niche.

  11. Microbial community in high arsenic shallow groundwater aquifers in Hetao Basin of Inner Mongolia, China.

    Science.gov (United States)

    Li, Ping; Wang, Yanhong; Dai, Xinyue; Zhang, Rui; Jiang, Zhou; Jiang, Dawei; Wang, Shang; Jiang, Hongchen; Wang, Yanxin; Dong, Hailiang

    2015-01-01

    A survey was carried out on the microbial community of 20 groundwater samples (4 low and 16 high arsenic groundwater) and 19 sediments from three boreholes (two high arsenic and one low arsenic boreholes) in a high arsenic groundwater system located in Hetao Basin, Inner Mongolia, using the 454 pyrosequencing approach. A total of 233,704 sequence reads were obtained and classified into 12-267 operational taxonomic units (OTUs). Groundwater and sediment samples were divided into low and high arsenic groups based on measured geochemical parameters and microbial communities, by hierarchical clustering and principal coordinates analysis. Richness and diversity of the microbial communities in high arsenic sediments are higher than those in high arsenic groundwater. Microbial community structure was significantly different either between low and high arsenic samples or between groundwater and sediments. Acinetobacter, Pseudomonas, Psychrobacter and Alishewanella were the top four genera in high arsenic groundwater, while Thiobacillus, Pseudomonas, Hydrogenophaga, Enterobacteriaceae, Sulfuricurvum and Arthrobacter dominated high arsenic sediments. Archaeal sequences in high arsenic groundwater were mostly related to methanogens. Biota-environment matching and co-inertia analyses showed that arsenic, total organic carbon, SO4(2-), SO4(2-)/total sulfur ratio, and Fe(2+) were important environmental factors shaping the observed microbial communities. The results of this study expand our current understanding of microbial ecology in high arsenic groundwater aquifers and emphasize the potential importance of microbes in arsenic transformation in the Hetao Basin, Inner Mongolia.

  12. Determinants of bacterial communities in Canadian agroforestry systems.

    Science.gov (United States)

    Banerjee, Samiran; Baah-Acheamfour, Mark; Carlyle, Cameron N; Bissett, Andrew; Richardson, Alan E; Siddique, Tariq; Bork, Edward W; Chang, Scott X

    2016-06-01

    Land-use change is one of the most important factors influencing soil microbial communities, which play a pivotal role in most biogeochemical and ecological processes. Using agroforestry systems as a model, this study examined the effects of land uses and edaphic properties on bacterial communities in three agroforestry types covering a 270 km soil-climate gradient in Alberta, Canada. Our results demonstrate that land-use patterns exert stronger effects on soil bacterial communities than soil zones in these agroforestry systems. Plots with trees in agroforestry systems promoted greater bacterial abundance and to some extent species richness, which was associated with more nutrient-rich soil resources. While Acidobacteria, Actinobacteria and Alphaproteobacteria were the dominant bacterial phyla and subphyla across land uses, Arthrobacter, Acidobacteria_Gp16, Burkholderia, Rhodanobacter and Rhizobium were the keystone taxa in these agroforestry systems. Soil pH and carbon contents emerged as the major determinants of bacterial community characteristics. We found non-random co-occurrence and modular patterns of soil bacterial communities, and these patterns were controlled by edaphic factors and not their taxonomy. Overall, this study highlights the drivers and co-occurrence patterns of soil microbial communities in agroforestry systems. © 2015 Society for Applied Microbiology and John Wiley & Sons Ltd.

  13. Endophytic bacterial flora in root and stem tissues of black pepper (Piper nigrum L.) genotype: isolation, identification and evaluation against Phytophthora capsici.

    Science.gov (United States)

    Aravind, R; Kumar, A; Eapen, S J; Ramana, K V

    2009-01-01

    To isolate and identify black pepper (Piper nigrum L) associated endophytic bacteria antagonistic to Phytophthora capsici causing foot rot disease. Endophytic bacteria (74) were isolated, characterized and evaluated against P. capsici. Six genera belong to Pseudomonas spp (20 strains), Serratia (1 strain), Bacillus spp. (22 strains), Arthrobacter spp. (15 strains), Micrococcus spp. (7 strains), Curtobacterium sp. (1 strain) and eight unidentified strains were isolated from internal tissues of root and stem. Three isolates, IISRBP 35, IISRBP 25 and IISRBP 17 were found effective for Phytophthora suppression in multilevel screening assays which recorded over 70% disease suppression in greenhouse trials. A species closest match (99% similarity) of IISRBP 35 was established as Pseudomonas aeruginosa (Pseudomonas EF568931), IISRBP 25 as P. putida (Pseudomonas EF568932), and IISRBP 17 as Bacillus megaterium (B. megaterium EU071712) based on 16S rDNA sequencing. Black pepper associated P. aeruginosa, P. putida and B. megaterium were identified as effective antagonistic endophytes for biological control of Phytophthora foot rot in black pepper. This work provides the first evidence for endophytic bacterial diversity in black pepper stem and roots, with biocontrol potential against P. capsici infection.

  14. Epithermal neutron activation analysis in applied microbiology

    International Nuclear Information System (INIS)

    Marina Frontasyeva

    2012-01-01

    Some results from applying epithermal neutron activation analysis at FLNP JINR, Dubna, Russia, in medical biotechnology, environmental biotechnology and industrial biotechnology are reviewed. In the biomedical experiments biomass from the blue-green alga Spirulina platensis (S. platensis) has been used as a matrix for the development of pharmaceutical substances containing such essential trace elements as selenium, chromium and iodine. The feasibility of target-oriented introduction of these elements into S. platensis biocomplexes retaining its protein composition and natural beneficial properties was shown. The absorption of mercury on growth dynamics of S. platensis and other bacterial strains was observed. Detoxification of Cr and Hg by Arthrobacter globiformis 151B was demonstrated. Microbial synthesis of technologically important silver nanoparticles by the novel actinomycete strain Streptomyces glaucus 71 MD and blue-green alga S. platensis were characterized by a combined use of transmission electron microscopy, scanning electron microscopy and energy-dispersive analysis of X-rays. It was established that the tested actinomycete S. glaucus 71 MD produces silver nanoparticles extracellularly when acted upon by the silver nitrate solution, which offers a great advantage over an intracellular process of synthesis from the point of view of applications. The synthesis of silver nanoparticles by S. platensis proceeded differently under the short-term and long-term silver action. (author)

  15. Changes of Bacterial Diversity Depend on the Spoilage of Fresh Vegetables

    Directory of Open Access Journals (Sweden)

    Dong Hwan Lee

    2011-04-01

    Full Text Available Almost 10~30% of vegetables were discarded by the spoilage from farms to tables. After harvest, vegetables are often spoiled by a wide variety of microorganisms including many bacterial and fungal species. This investigation was conducted to extent the knowledge of relationship the spoilage of vegetables and the diversity of microbes. The total aerobic bacterial numbers in fresh lettuce, perilla leaf, and chicory were 2.6~2.7×106, 4.6×105, 1.2×106 CFU/g of fresh weight, respectively. The most common bacterial species were Pseudomonas spp., Alysiella spp., and Burkholderia spp., and other 18 more genera were involved in. After one week of incubation of those vegetables at 28℃, the microbial diversity had been changed. The total aerobic bacterial numbers increased to 1.1~4.6×108, 4.9×107, and 7.6×108 CFU/g of fresh weight for lettuce, perilla leaf, and chicory that is about 102 times increased bacterial numbers than that before spoilage. However, the diversity of microbes isolated had been simplified and fewer bacterial species had been isolated. The most bacterial population (~48% was taken up by Pseudomonas spp., and followed by Arthrobacter spp. and Bacillus spp. The spoilage activity of individual bacterial isolates had been tested using axenic lettuce plants. Among tested isolates, Pseudomonas fluorescence and Pantoea agglomerans caused severe spoilage on lettuce.

  16. Biodiversity of bacterial ecosystems in traditional Egyptian Domiati cheese.

    Science.gov (United States)

    El-Baradei, Gaber; Delacroix-Buchet, Agnès; Ogier, Jean-Claude

    2007-02-01

    Bacterial biodiversity occurring in traditional Egyptian soft Domiati cheese was studied by PCR-temporal temperature gel electrophoresis (TTGE) and PCR-denaturing gradient gel electrophoresis (DGGE). Bands were identified using a reference species database (J.-C. Ogier et al., Appl. Environ. Microbiol. 70:5628-5643, 2004); de novo bands having nonidentified migration patterns were identified by DNA sequencing. Results reveal a novel bacterial profile and extensive bacterial biodiversity in Domiati cheeses, as reflected by the numerous bands present in TTGE and DGGE patterns. The dominant lactic acid bacteria (LAB) identified were as follows: Leuconostoc mesenteroides, Lactococcus garvieae, Aerococcus viridans, Lactobacillus versmoldensis, Pediococcus inopinatus, and Lactococcus lactis. Frequent non-LAB species included numerous coagulase-negative staphylococci, Vibrio spp., Kocuria rhizophila, Kocuria kristinae, Kocuria halotolerans, Arthrobacter spp./Brachybacterium tyrofermentans. This is the first time that the majority of these species has been identified in Domiati cheese. Nearly all the dominant and frequent bacterial species are salt tolerant, and several correspond to known marine bacteria. As Domiati cheese contains 5.4 to 9.5% NaCl, we suggest that these bacteria are likely to have an important role in the ripening process. This first systematic study of the microbial composition of Domiati cheeses reveals great biodiversity and evokes a role for marine bacteria in determining cheese type.

  17. Biodiversity of Bacterial Ecosystems in Traditional Egyptian Domiati Cheese▿

    Science.gov (United States)

    El-Baradei, Gaber; Delacroix-Buchet, Agnès; Ogier, Jean-Claude

    2007-01-01

    Bacterial biodiversity occurring in traditional Egyptian soft Domiati cheese was studied by PCR-temporal temperature gel electrophoresis (TTGE) and PCR-denaturing gradient gel electrophoresis (DGGE). Bands were identified using a reference species database (J.-C. Ogier et al., Appl. Environ. Microbiol. 70:5628-5643, 2004); de novo bands having nonidentified migration patterns were identified by DNA sequencing. Results reveal a novel bacterial profile and extensive bacterial biodiversity in Domiati cheeses, as reflected by the numerous bands present in TTGE and DGGE patterns. The dominant lactic acid bacteria (LAB) identified were as follows: Leuconostoc mesenteroides, Lactococcus garvieae, Aerococcus viridans, Lactobacillus versmoldensis, Pediococcus inopinatus, and Lactococcus lactis. Frequent non-LAB species included numerous coagulase-negative staphylococci, Vibrio spp., Kocuria rhizophila, Kocuria kristinae, Kocuria halotolerans, Arthrobacter spp./Brachybacterium tyrofermentans. This is the first time that the majority of these species has been identified in Domiati cheese. Nearly all the dominant and frequent bacterial species are salt tolerant, and several correspond to known marine bacteria. As Domiati cheese contains 5.4 to 9.5% NaCl, we suggest that these bacteria are likely to have an important role in the ripening process. This first systematic study of the microbial composition of Domiati cheeses reveals great biodiversity and evokes a role for marine bacteria in determining cheese type. PMID:17189434

  18. Microbial community in high arsenic shallow groundwater aquifers in Hetao Basin of Inner Mongolia, China.

    Directory of Open Access Journals (Sweden)

    Ping Li

    Full Text Available A survey was carried out on the microbial community of 20 groundwater samples (4 low and 16 high arsenic groundwater and 19 sediments from three boreholes (two high arsenic and one low arsenic boreholes in a high arsenic groundwater system located in Hetao Basin, Inner Mongolia, using the 454 pyrosequencing approach. A total of 233,704 sequence reads were obtained and classified into 12-267 operational taxonomic units (OTUs. Groundwater and sediment samples were divided into low and high arsenic groups based on measured geochemical parameters and microbial communities, by hierarchical clustering and principal coordinates analysis. Richness and diversity of the microbial communities in high arsenic sediments are higher than those in high arsenic groundwater. Microbial community structure was significantly different either between low and high arsenic samples or between groundwater and sediments. Acinetobacter, Pseudomonas, Psychrobacter and Alishewanella were the top four genera in high arsenic groundwater, while Thiobacillus, Pseudomonas, Hydrogenophaga, Enterobacteriaceae, Sulfuricurvum and Arthrobacter dominated high arsenic sediments. Archaeal sequences in high arsenic groundwater were mostly related to methanogens. Biota-environment matching and co-inertia analyses showed that arsenic, total organic carbon, SO4(2-, SO4(2-/total sulfur ratio, and Fe(2+ were important environmental factors shaping the observed microbial communities. The results of this study expand our current understanding of microbial ecology in high arsenic groundwater aquifers and emphasize the potential importance of microbes in arsenic transformation in the Hetao Basin, Inner Mongolia.

  19. Cloning of genes and developing transgenic crops with enhanced tolerance to salinity and drought (abstract)

    International Nuclear Information System (INIS)

    Bansal, K.C.; Chinnusamy, V.; Tayal, D.; Das, A.; Goel, D.; Yadav, V.; Singh, A.K.; Lakhshmi, K.

    2005-01-01

    Abiotic stresses represent the most limiting factors affecting agricultural productivity. In India more than 60% of total cultivated land is still rainfed and crops experience frequent droughts. Thus, we need to develop transgenic crops tolerant to drought, and other related abiotic stress factors such as salinity, low and high temperature stresses. At the National Research Centre on Plant Biotechnology, Indian Agricultural Research Institute (ICAR), we have initiated a programme on developing transgenic crops tolerant to a range of abiotic stresses. The major emphasis is on developing transgenic potato, tomato, mustard, rice and wheat. While, transgenic plants of potato. tomato and mustard have already been generated with osmotin gene and are at different stages of testing, other key genes imparting tolerance to abiotic stresses are being isolated from different species for producing transgenic rice and wheat cultivars tolerant to multiple stresses. Genes that have been isolated in our laboratory include ascorbate peroxidase gene (TaApx) and genes encoding transcription factor, CBFs (TaCBF2 and TaCBP3) from a drought tolerant wheat cultivar (C306), Lea1 cDNA from Brassica species, codA from Arthrobacter globiformis, and otsBA operon from E. coli. Apart from these stress-related genes, we have isolated a few stress-inducible promoters for deploying them in gene stacking in developing transgenic crops with enhanced tolerance to multiple abiotic stresses. The results will be presented. (author)

  20. Effect of vacuum and modified atmosphere packaging on the microbiological, chemical and sensory properties of tropical red drum (Sciaenops ocellatus) fillets stored at 4°C.

    Science.gov (United States)

    Silbande, Adèle; Adenet, Sandra; Chopin, Christine; Cornet, Josiane; Smith-Ravin, Juliette; Rochefort, Katia; Leroi, Françoise

    2018-02-02

    The effect of vacuum (VP - 4°C) and CO 2 /N 2 -atmosphere (MAP - 4°C) packaging on the quality of red drum fillets compared with whole gutted iced fish was investigated. A metagenomic approach, bacterial enumeration and isolation, biochemical and sensory analyses were carried out. The organoleptic rejection of whole fish was observed at day 15 whereas VP and MAP fillets appeared unacceptable only after 29days. At these dates, total mesophilic counts reached 10 7 -10 8 CFU g -1 . According to Illumina MiSeq sequencing, Arthrobacter, Chryseobacterium, Brevibacterium, Staphylococcus and Kocuria were the main genera of the fresh red drum fillets. At the sensory rejection time, lactic acid bacteria (LAB), particularly Carnobacterium sp., dominated the microbiota of both types of packaging. The pH value of fresh samples was between 5.96 and 6.37 and did not vary greatly in all trials. Total volatile basic nitrogen (TVBN) and trimethylamine (TMA) concentrations were low and not represent reliable indicators of the spoilage, contrary to some biogenic amines (cadaverine, putrescine and tyramine). Chilled packed fillets of red drum have an extended shelf-life compared to whole gutted iced fish. Overall, few differences in sensory and microbial quality were observed between the VP and MAP samples. Next-Generation Sequencing (NGS) provided data on the microbiota of a tropical fish. Copyright © 2017 Elsevier B.V. All rights reserved.

  1. Removal of gasoline volatile organic compounds via air biofiltration

    International Nuclear Information System (INIS)

    Miller, R.S.; Saberiyan, A.G.; Esler, C.T.; DeSantis, P.; Andrilenas, J.S.

    1995-01-01

    Volatile organic compounds (VOCs) generated by vapor extraction and air-stripping systems can be biologically treated in an air biofiltration unit. An air biofilter consists of one or more beds of packing material inoculated with heterotrophic microorganisms capable of degrading the organic contaminant of concern. Waste gases and oxygen are passed through the inoculated packing material, where the microorganisms will degrade the contaminant and release CO 2 + H 2 O. Based on data obtained from a treatability study, a full-scale unit was designed and constructed to be used for treating gasoline vapors generated by a vapor-extraction and groundwater-treatment system at a site in California. The unit is composed of two cylindrical reactors with a total packing volume of 3 m 3 . Both reactors are packed with sphagnum moss and inoculated with hydrocarbon-degrading microorganisms of Pseudomonas and Arthrobacter spp. The two reactors are connected in series for air-flow passage. Parallel lines are used for injection of water, nutrients, and buffer to each reactor. Data collected during the startup program have demonstrated an air biofiltration unit with high organic-vapor-removal efficiency

  2. Structural basis and catalytic mechanism for the dual functional endo-beta-N-acetylglucosaminidase A.

    Directory of Open Access Journals (Sweden)

    Jie Yin

    Full Text Available Endo-beta-N-acetylglucosaminidases (ENGases are dual specificity enzymes with an ability to catalyze hydrolysis and transglycosylation reactions. Recently, these enzymes have become the focus of intense research because of their potential for synthesis of glycopeptides. We have determined the 3D structures of an ENGase from Arthrobacter protophormiae (Endo-A in 3 forms, one in native form, one in complex with Man(3GlcNAc-thiazoline and another in complex with GlcNAc-Asn. The carbohydrate moiety sits above the TIM-barrel in a cleft region surrounded by aromatic residues. The conserved essential catalytic residues - E173, N171 and Y205 are within hydrogen bonding distance of the substrate. W216 and W244 regulate access to the active site during transglycosylation by serving as "gate-keepers". Interestingly, Y299F mutation resulted in a 3 fold increase in the transglycosylation activity. The structure provides insights into the catalytic mechanism of GH85 family of glycoside hydrolases at molecular level and could assist rational engineering of ENGases.

  3. Bacteria Present in Comadia redtenbacheri Larvae (Lepidoptera: Cossidae).

    Science.gov (United States)

    Hernández-Flores, L; Llanderal-Cázares, C; Guzmán-Franco, A W; Aranda-Ocampo, S

    2015-09-01

    The external and internal culturable bacterial community present in the larvae of Comadia redtenbacheri Hammerschmidt, an edible insect, was studied. Characterization of the isolates determined the existence of 18 morphotypes and phylogenetic analysis of the 16S rRNA gene revealed the existence of Paenibacillus sp., Bacillus safensis, Pseudomonas sp., Bacillus pseudomycoides, Corynebacterium variabile, Enterococcus sp., Gordonia sp., Acinetobacter calcoaceticus, Arthrobacter sp., Micrococcus sp., and Bacillus cereus. Greater diversity of bacteria was found in those larvae obtained from vendors than in those directly taken from Agave plants in nature. Many of the larvae obtained from vendors presented signs of potential disease, and after the analysis, results showed a greater bacterial community compared with the larvae with a healthy appearance. This indicates that bacterial flora can vary in accordance with how the larvae are handled during extraction, collection, and transport. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  4. Actinobacterial community structure in the Polar Frontal waters of the Southern Ocean of the Antarctica using Geographic Information System (GIS: A novel approach to study Ocean Microbiome

    Directory of Open Access Journals (Sweden)

    P. Sivasankar

    2018-04-01

    Full Text Available Integration of microbiological data and geographical locations is necessary to understand the spatiotemporal patterns of the microbial diversity of an ecosystem. The Geographic Information System (GIS to map and catalogue the data on the actinobacterial diversity of the Southern Ocean waters was completed through sampling and analysis. Water samples collected at two sampling stations viz. Polar Front 1 (Station 1 and Polar Front 2 (Station 2 during 7th Indian Scientific Expedition to the Indian Ocean Sector of the Southern Ocean (SOE-2012-13 were used for analysis. At the outset, two different genera of Actinobacteria were recorded at both sampling stations. Streptomyces was the dominanted with the high score (> 60%, followed by Nocardiopsis (< 30% at both the sampling stations-Polar Front 1 and Polar Front 2-along with other invasive genera such as Agrococcus, Arthrobacter, Cryobacterium, Curtobacterium, Microbacterium, Marisediminicola, Rhodococcus and Kocuria. This data will help to discriminate the diversity and distribution pattern of the Actinobacteria in the Polar Frontal Region of the Southern Ocean waters. It is a novel approach useful for geospatial cataloguing of microbial diversity from extreme niches and in various environmental gradations. Furthermore, this research work will act as the milestone for bioprospecting of microbial communities and their products having potential applications in healthcare, agriculture and beneficial to mankind. Hence, this research work would have significance in creating a database on microbial communities of the Antarctic ecosystem. Keywords: Antarctica, Marine actinobacteria, Southern ocean, GIS, Polar Frontal waters, Microbiome

  5. Phenotypic and molecular characterization of bacterial populations isolated from diesel-contaminated soil and treated by two bioremediation technologies

    International Nuclear Information System (INIS)

    Arrieta R, Olga M; Rivera R, Angela P; Rojano, Benjamin; Ruiz, Orlando; Correa, Margarita M; Cienfuegos Gallet, Astrid V; Arias, Lida; Cardona G, Santiago A

    2012-01-01

    In this study bioremediation is presented as an alternative for the recovery of contaminated ecosystems. In this work an experimental diesel spill on pasture land was remediated using two bioremediation technologies: natural attenuation, which is the natural capability of indigenous microorganisms to degrade a xenobiotic component in a determined time, and biostimulation, which consist in the acceleration of the degradation process through the stimulation of the metabolism of indigenous microorganisms by the addition of nutrients (P and N) to the media. Results of respirometry assays indicated that both treatments produced significant levels of hydrocarbon removal but the biostimulation treatment stranded out with 98.17% degradation. Seven bacterial isolates were obtained from these treatments which according to their molecular characterization and phylogenetic analysis belong to the genus: Enterobacter, Bacillus, Arthrobacter, Sanguibacter, Staphylococcus and Flavobacterium. All isolates were able to metabolize diesel as a carbon and energy source; for this reason and taking into account that for some of these microorganisms their role in bioremediation have not been extensively studied, it is recommended to continue with their evaluation to know their real potential for the solution of environmental problems.

  6. BIORREMEDIACIÓN DE UN SUELO CON DIESEL MEDIANTE EL USO DE MICROORGANISMOS AUTÓCTONOS

    Directory of Open Access Journals (Sweden)

    ARRIETA RAMÍREZ OLGA MARIA

    2012-07-01

    Full Text Available En este estudio, se aisló y caracterizó bioquímica y molecularmente un consorcio bacteriano capaz de degradar los diferentes hidrocarburos presentes en un combustible diesel,conformado por los siguientes géneros: Enterobacter sp, Bacillus sp, Staphylococcus aureus, Sanguibacter soli, Arthrobacter sp y Flavobacterium sp, a partir de un suelo contaminado con diesel a escala de laboratorio, y tratado mediante 2 tecnologías de biorremediación: atenuación natural y bioestimulación. Se definió como parámetro de control la concentración de Hidrocarburos Totales del Petróleo (HTP y para el cual, se obtuvo una reducción en la concentración en un periodo de 4 meses de 36,86% para atenuación natural y 50,99% para bioestimulación. La medición de la eficiencia de remoción de hidrocarburos se cuantificó por cromatografía de gases acoplada a masas (GC-MS.

  7. Ecotoxicological effect characterisation of widely used organic UV filters.

    Science.gov (United States)

    Kaiser, D; Sieratowicz, A; Zielke, H; Oetken, M; Hollert, H; Oehlmann, J

    2012-04-01

    Chemical UV filters are used in sun protection and personal care products in order to protect consumers from skin cancer induced by ultraviolet (UV) radiation. The present study aims to evaluate the effects of three common UV filters butyl-methoxydibenzoylmethane (B-MDM) ethylhexyl-methoxycinnamate (EHMC) and octocrylene (OCR) on aquatic organism, focussing particularly on infaunal and epibentic invertebrates (Chironomus riparius, Lumbriculus variegatus, Melanoides tuberculata and Potamopyrgus antipodarum). Due to their life habits, these organism are especially affected by lipophilic substances. Additionally, two direct sediment contact assays utilising zebra fish (Danio rerio) embryos and bacteria (Arthrobacter globiformis) were conducted. EHMC caused a toxic effect on reproduction in both snails with lowest observed effect concentrations (LOEC) of 0.4 mg/kg (Potamopyrgus antipodarum) and 10 mg/kg (Melanoides tuberculata). At high concentrations sublethal effects could be observed for D. rerio after exposure to EHMC (NOEC 100 mg/kg). B-MDM and OCR showed no effects on any of the tested organism. Copyright © 2011 Elsevier Ltd. All rights reserved.

  8. Ecotoxicological effect characterisation of widely used organic UV filters

    International Nuclear Information System (INIS)

    Kaiser, D.; Sieratowicz, A.; Zielke, H.; Oetken, M.; Hollert, H.; Oehlmann, J.

    2012-01-01

    Chemical UV filters are used in sun protection and personal care products in order to protect consumers from skin cancer induced by ultraviolet (UV) radiation. The present study aims to evaluate the effects of three common UV filters butyl-methoxydibenzoylmethane (B-MDM) ethylhexyl-methoxycinnamate (EHMC) and octocrylene (OCR) on aquatic organism, focussing particularly on infaunal and epibentic invertebrates (Chironomus riparius, Lumbriculus variegatus, Melanoides tuberculata and Potamopyrgus antipodarum). Due to their life habits, these organism are especially affected by lipophilic substances. Additionally, two direct sediment contact assays utilising zebra fish (Danio rerio) embryos and bacteria (Arthrobacter globiformis) were conducted. EHMC caused a toxic effect on reproduction in both snails with lowest observed effect concentrations (LOEC) of 0.4 mg/kg (Potamopyrgus antipodarum) and 10 mg/kg (Melanoides tuberculata). At high concentrations sublethal effects could be observed for D. rerio after exposure to EHMC (NOEC 100 mg/kg). B-MDM and OCR showed no effects on any of the tested organism. - Highlights: ► Ecotoxicological effects of common used UV filters on aquatic invertebrates. ► Butyl-methoxydibenzoylmethane, ethylhexyl-methoxycinnamate, and octocrylene used. ► Sediment based test systems. ► Ethylhexyl-methoxycinnamate caused a toxic effect on reproduction in both snails. ► Other substances showed no effects on any of the tested organism. - Ethylhexyl-methoxycinnamate caused a toxic effect on reproduction in both snails. Butyl-methoxydibenzoylmethane and octocrylene showed no effects on any of the tested organism.

  9. Microbiological Quality Assessment of Game Meats at Retail in Japan.

    Science.gov (United States)

    Asakura, Hiroshi; Kawase, Jun; Ikeda, Tetsuya; Honda, Mioko; Sasaki, Yoshimasa; Uema, Masashi; Kabeya, Hidenori; Sugiyama, Hiromu; Igimi, Shizunobu; Takai, Shinji

    2017-12-01

    In this study, we examined the prevalence of Shiga toxin-producing Escherichia coli and Salmonella spp. and the distribution of indicator bacteria in 248 samples of game meats (120 venison and 128 wild boar) retailed between November 2015 and March 2016 in Japan. No Salmonella spp. were detected in any of the samples, whereas Shiga toxin-producing Escherichia coli serotype OUT:H25 (stx 2d + , eae - ) was isolated from one deer meat sample, suggesting a possible source for human infection. Plate count assays indicated greater prevalence of coliforms and E. coli in wild boar meat than in venison, whereas their prevalence in processing facilities showed greater variation than in animal species. The 16S rRNA ion semiconductor sequencing analysis of 24 representative samples revealed that the abundances of Acinetobacter and Arthrobacter spp. significantly correlated with the prevalence of E. coli, and quantitative PCR analyses in combination with selective plate count assay verified these correlations. To our knowledge, this is the first report to characterize the diversity of microorganisms of game meats at retail in Japan, together with identification of dominant microbiota. Our data suggest the necessity of bottom-up hygienic assessment in areas of slaughtering and processing facilities to improve microbiological safety.

  10. Phytoremediation of mercury in pristine and crude oil contaminated soils: Contributions of rhizobacteria and their host plants to mercury removal.

    Science.gov (United States)

    Sorkhoh, N A; Ali, N; Al-Awadhi, H; Dashti, N; Al-Mailem, D M; Eliyas, M; Radwan, S S

    2010-11-01

    The rhizospheric soils of three tested legume crops: broad beans (Vicia faba), beans (Phaseolus vulgaris) and pea (Pisum sativum), and two nonlegume crops: cucumber (Cucumis sativus) and tomato, (Lycopersicon esculentum) contained considerable numbers (the magnitude of 10(5)g(-1) soil) of bacteria with the combined potential for hydrocarbon-utilization and mercury-resistance. Sequencing of the 16S rRNA coding genes of rhizobacteria associated with broad beans revealed that they were affiliated to Citrobacter freundii, Enterobacter aerogenes, Exiquobacterium aurantiacum, Pseudomonas veronii, Micrococcus luteus, Brevibacillus brevis, Arthrobacter sp. and Flavobacterium psychrophilum. These rhizobacteria were also diazotrophic, i.e. capable of N(2) fixation, which makes them self-sufficient regarding their nitrogen nutrition and thus suitable remediation agents in nitrogen-poor soils, such as the oily desert soil. The crude oil attenuation potential of the individual rhizobacteria was inhibited by HgCl(2), but about 50% or more of this potential was still maintained in the presence of up to 40 mgl(-1) HgCl(2). Rhizobacteria-free plants removed amounts of mercury from the surrounding media almost equivalent to those removed by the rhizospheric bacterial consortia in the absence of the plants. It was concluded that both the collector plants and their rhizospheric bacterial consortia contributed equivalently to mercury removal from soil. Copyright © 2010 Elsevier Inc. All rights reserved.

  11. Application of microbiological methods for secondary oil recovery from the Carpathian crude oil reservoirs

    Energy Technology Data Exchange (ETDEWEB)

    Karaskiewicz, J

    1974-01-01

    The investigation made it possible to isolate from different ecologic environmental (soil, crude oil, formation water, industrial wastes) bacteria cultures of the genus Arthrobacter, Clostridium, Mycobacterium, Peptococcus, and Pseudomonas. These heterotrophic bacteria are characterized by a high metabolic and biogeochemical activity hydrocarbon transformation. Experiments on a technical scale were conducted from 1961 to 1971 in 20 wells; in this study, only the 16 most typical examples are discussed. The experiments were conducted in Carpathian crude oil reservoirs. To each well, a 500:1 mixture of the so-called bacteria vaccine (containing an active biomass of cultures obtained by a specific cultivation method and holding 6 x 10/sup 5/ bacteria cells in 1 ml of fluid, 2,000 kg of molasses, and 50 cu m of water originating from the reservoir submitted to treatment) was injected at 500 to 1,200 m. The intensification of the microbiological processes in the reservoir was observed. This phenomenon occurred not only in the wells to which the bacteria vaccine was injected, but also in the surrounding producing wells. At the same time, an increase in the crude oil production occurred on the average within the range from 20 to 200% and the surpluses of crude oil production continued for 2 to 8 yr. (92 refs.)

  12. Effects of cadmium and lead upon the indigenous heterotrophic microflora in the aqueous environment of the brackish estuary-water of the river Weser

    Energy Technology Data Exchange (ETDEWEB)

    Thormann, D

    1975-01-01

    In agar media (10% salinity) containing Cd or Pb bacterial numbers were progressively reduced at 0.5 to 400 ppM Cd and at 100 to 400 ppM Pb. Only a few bacteria were able to form colonies at the highest concentrations. Lower salinity and low peptone-yeast-extract-concentrations of the medium increased the toxicity of Pb. The appearance of several brown-black pigmented colonies on the plates containing more than 200 ppM Pb was observed, but no dark pigment was noted when the same bacteria were grown in the absence of Pb. Different concentrations of Cd or Pb were added to water samples (as batch cultures) of the Weser Estuary (West Germany). The development of the indigenous microbial population was observed by subsequent counting of the viable heterotrophic bacteria on agar media. Cd was more toxic than Pb; there were differences in the kind of toxicity. The dissolved concentrations of Cd and Pb in the batch cultures were analyzed by atomic absorption. Cd dissolved considerably better than Pb in brackish water. Cd- and Pb-sensitive bacteria were isolated by a replica plating technique to carry out subsequent experiments on the microbial uptake of heavy metals. The most sensitive bacteria were growth-inhibited at 0.1 ppM Cd and Pb. Arthrobacter marinus is mentioned.

  13. Quantitation of immunoadsorbed flavoprotein oxidases by luminol-mediated chemiluminescence.

    Science.gov (United States)

    Hinkkanen, A; Maly, F E; Decker, K

    1983-04-01

    The detection of the flavoenzymes 6-hydroxy-L-nicotine oxidase and 6-hydroxy-D-nicotine oxidase at the sub-femtomol level was achieved by coupling the reaction of the immunoadsorbed proteins to the peroxidase-catalysed oxidation of luminol. The H2O2-producing oxidases retained their full activity when bound to the respective immobilized antibodies. This fact allowed the concentration of the enzymes from very dilute solutions and the quantitative assay of their activities in the microU range. Due to strict stereoselectivity and the absence of immunological cross-reactivity, the two flavoproteins could be determined in the same solution. This method was used to measure the 6-hydroxy-D-nicotine oxidase and 6-hydroxy-L-nicotine oxidase activities in Escherichia coli RR1 and different Arthrobacter strains cultured under non-inducing conditions. The same activity ratio of 6-hydroxy-L-nicotine oxidase/6-hydroxy-D-nicotine oxidase as in D L-nicotine-induced cells of A. oxidans was observed in non-induced wild type and in riboflavin-requiring (rf-) mutant cells of this aerob.

  14. Acetate biostimulation as an effective treatment for cleaning up alkaline soil highly contaminated with Cr(VI).

    Science.gov (United States)

    Lara, Paloma; Morett, Enrique; Juárez, Katy

    2017-11-01

    Stimulation of microbial reduction of Cr(VI) to the less toxic and less soluble Cr(III) through electron donor addition has been regarded as a promising approach for the remediation of chromium-contaminated soil and groundwater sites. However, each site presents different challenges; local physicochemical characteristics and indigenous microbial communities influence the effectiveness of the biostimulation processes. Here, we show microcosm assays stimulation of microbial reduction of Cr(VI) in highly alkaline and saline soil samples from a long-term contaminated site in Guanajuato, Mexico. Acetate was effective promoting anaerobic microbial reduction of 15 mM of Cr(VI) in 25 days accompanied by an increase in pH from 9 to 10. Our analyses showed the presence of Halomonas, Herbaspirillum, Nesterenkonia/Arthrobacter, and Bacillus species in the soil sample collected. Moreover, from biostimulated soil samples, it was possible to isolate Halomonas spp. strains able to grow at 32 mM of Cr(VI). Additionally, we found that polluted groundwater has bacterial species different to those found in soil samples with the ability to resist and reduce chromate using acetate and yeast extract as electron donors.

  15. Substrate interactions of benzene, toluene, and para-xylene during microbial degradation by pure cultures and mixed culture aquifer slurries

    International Nuclear Information System (INIS)

    Alvarez, P.J.J.; Vogel, T.M.

    1991-01-01

    Release of petroleum hydrocarbons in the environment is a widespread occurrence. One particular concern is the contamination of drinking water sources by the toxic, water-soluble, and mobile petroleum components benzene, toluene, and xylene (BTX). Benzene, toluene, and p-xylene (BTX) were degraded by indigenous mixed cultures in sandy aquifer material and by two pure cultures isolated from the same site. Although BTX compounds have a similar chemical structure, the fate of individual BTX compounds differed when the compounds were fed to each pure culture and mixed culture aquifer slurries. The identification of substrate interactions aided the understanding of this behavior. Beneficial substrate interactions included enhanced degradation of benzene-dependent degradation of toluene and p-xylene by Arthrobacter sp. strain HCB. Detrimental substrate interactions included retardation in benzene and toluene degradation by the presence of p-xylene in both aquifer slurries and Pseudomonas incubations. The catabolic diversity of microbes in the environment precludes generalizations about the capacity of individual BTX compounds to enhance or inhibit the degradation of other BTX compounds

  16. Metagenomic Analysis of Airborne Bacterial Community and Diversity in Seoul, Korea, during December 2014, Asian Dust Event.

    Science.gov (United States)

    Cha, Seho; Srinivasan, Sathiyaraj; Jang, Jun Hyeong; Lee, Dongwook; Lim, Sora; Kim, Kyung Sang; Jheong, Weonhwa; Lee, Dong-Won; Park, Eung-Roh; Chung, Hyun-Mi; Choe, Joonho; Kim, Myung Kyum; Seo, Taegun

    2017-01-01

    Asian dust or yellow sand events in East Asia are a major issue of environmental contamination and human health, causing increasing concern. A high amount of dust particles, especially called as particulate matter 10 (PM10), is transported by the wind from the arid and semi-arid tracks to the Korean peninsula, bringing a bacterial population that alters the terrestrial and atmospheric microbial communities. In this study, we aimed to explore the bacterial populations of Asian dust samples collected during November-December 2014. The dust samples were collected using the impinger method, and the hypervariable regions of the 16S rRNA gene were amplified using PCR followed by pyrosequencing. Analysis of the sequencing data were performed using Mothur software. The data showed that the number of operational taxonomic units and diversity index during Asian dust events were higher than those during non-Asian dust events. At the phylum level, the proportions of Proteobacteria, Actinobacteria, and Firmicutes were different between Asian dust and non-Asian dust samples. At the genus level, the proportions of the genus Bacillus (6.9%), Arthrobacter (3.6%), Blastocatella (2%), Planomicrobium (1.4%) were increased during Asian dust compared to those in non-Asian dust samples. This study showed that the significant relationship between bacterial populations of Asian dust samples and non-Asian dust samples in Korea, which could significantly affect the microbial population in the environment.

  17. Accumulation of thorium and uranium by microbes. The effect of pH, concentration of metals, and time course on the accumulation of both elements using streptomyces levoris

    International Nuclear Information System (INIS)

    Tsuruta, Takehiko

    2006-01-01

    The accumulation of thorium and uranium by various microorganisms from a solution containing both metals at pH 3.5 was examined. Among the tested species, a high accumulation ability for thorium was exhibited by strains of gram-positive bacteria, such as Arthrobacter nicotianae, Bacillus megaterium, B. subtilis, Micrococcus luteus, Rhodococcus erythropolis, and Streptomyces levoris. Though uranium was accumulated in small amounts by most of microorganisms. A. nicotianae, S. flavoviridis, and S. levoris had relatively high uranium accumulation abilities. In these high performance thorium- and uranium-accumulating microorganisms, S. levoris, which accumulated the largest amount of uranium from the solution containing only uranium at pH 3.5, accumulated about 300 μmol thorium and 133 μmol uranium per gram dry weight of microbial cells from a solution containing both thorium and uranium at pH 3.5. The amount and time course of the thorium accumulation were almost unaffected by the co-existing uranium, while those of uranium were strongly affected by the co-existing thorium. The effects of pH, the thorium and uranium concentrations, and time course on both metal accumulations were also evaluated by numerical formulas. (author)

  18. Most hydrocarbonoclastic bacteria in the total environment are diazotrophic, which highlights their value in the bioremediation of hydrocarbon contaminants.

    Science.gov (United States)

    Dashti, Narjes; Ali, Nedaa; Eliyas, Mohamed; Khanafer, Majida; Sorkhoh, Naser A; Radwan, Samir S

    2015-01-01

    Eighty-two out of the 100 hydrocarbonoclastic bacterial species that have been already isolated from oil-contaminated Kuwaiti sites, characterized by 16S rRNA nucleotide sequencing, and preserved in our private culture collection, grew successfully in a mineral medium free of any nitrogenous compounds with oil vapor as the sole carbon source. Fifteen out of these 82 species were selected for further study based on the predominance of most of the isolates in their specific sites. All of these species tested positive for nitrogenase using the acetylene reduction reaction. They belonged to the genera Agrobacterium, Sphingomonas, and Pseudomonas from oily desert soil and Nesiotobacter, Nitratireductor, Acinetobacter, Alcanivorax, Arthrobacter, Marinobacter, Pseudoalteromonas, Vibrio, Diatzia, Mycobacterium, and Microbacterium from the Arabian/Persian Gulf water body. A PCR-DGGE-based sequencing analysis of nifH genes revealed the common occurrence of the corresponding genes among all the strains tested. The tested species also grew well and consumed crude oil effectively in NaNO3 -containing medium with and without nitrogen gas in the top space. On the other hand, these bacteria only grew and consumed crude oil in the NaNO3 -free medium when the top space gas contained nitrogen. We concluded that most hydrocarbonoclastic bacteria are diazotrophic, which allows for their wide distribution in the total environment. Therefore, these bacteria are useful for the cost-effective, environmentally friendly bioremediation of hydrocarbon contaminants.

  19. Crystallization and preliminary crystallographic analysis of maganese(II)-dependent 2,3-dihydroxybiphenyl 1,2-dioxygenase from Bacillus sp. JF8

    International Nuclear Information System (INIS)

    Senda, Miki; Hatta, Takashi; Kimbara, Kazuhide; Senda, Toshiya

    2010-01-01

    A thermostable manganese(II)-dependent 2,3-dihydroxybiphenyl-1,2-dioxygenase derived from Bacillus sp. JF8 was crystallized in two forms using the sitting-drop vapour-diffusion method. Both crystals diffracted to approximately 1.3 Å resolution. A thermostable manganese(II)-dependent 2,3-dihydroxybiphenyl-1,2-dioxygenase derived from Bacillus sp. JF8 was crystallized. The initial screening for crystallization was performed by the sitting-drop vapour-diffusion method using a crystallization robot, resulting in the growth of two crystal forms. The first crystal belonged to space group P1, with unit-cell parameters a = 62.7, b = 71.4, c = 93.6 Å, α = 71.2, β = 81.0, γ = 64.0°, and diffracted to 1.3 Å resolution. The second crystal belonged to space group I222, with unit-cell parameters a = 74.2, b = 90.8, c = 104.3 Å, and diffracted to 1.3 Å resolution. Molecular-replacement trials using homoprotocatechuate 2,3-dioxygenase from Arthrobacter globiformis (28% amino-acid sequence identity) as a search model provided a satisfactory solution for both crystal forms

  20. Insecticidal Activity of Isolated Bacteria from Hyphantria cunea (Drury (Lepidoptera: Arctiidae

    Directory of Open Access Journals (Sweden)

    Nurcan Albayrak İskender

    2017-04-01

    Full Text Available The fall webworm (Hyphantria cunea is a polyphagous pest with numerous host plants. In the present study, the bacterial flora of H.cunea was investigated to identify new organisms that can be used as microbial control agent against the pest. Six bacteria were isolated and cultured from H. cunea. Some morphological, biochemical and other phenotypic characteristics (with API 20E, API 50 CH, API Staph and API Coryne kits of bacterial isolates were determined. In addition, 16S rRNA gene region was sequenced. As a result of the studies conducted, bacterial isolates were identified as Lysinibacillus sphaericus (Abk1, Bacillus amyloliquefaciens (Abk2, Staphylococcus sciuri (Abk4, Kocuria palustris (Abk6, Arthrobacter arilaitensis (Abk7 and Microbacterium oxydans (Abk8. All bacterial isolates were tested for 12 days against third-fourth instar larvae of H. cunea. The highest insecticidal activity was obtained from L. sphaericus (Abk1 with 30% after application (p<0.05. These results indicate that L. sphaericus (Abk1 can be taken into account in the microbial pest control of H. cunea. In the future, further studies will be conducted by using pathogenicity enrichment strategies of L. sphaericus (Abk1 (ex. combining with other entomopathogens or insecticides in order to increase the effectiveness on H. cunea.

  1. Variability of sediment-contact tests in freshwater sediments with low-level anthropogenic contamination - Determination of toxicity thresholds

    International Nuclear Information System (INIS)

    Hoess, S.; Ahlf, W.; Fahnenstich, C.; Gilberg, D.; Hollert, H.; Melbye, K.; Meller, M.; Hammers-Wirtz, M.; Heininger, P.; Neumann-Hensel, H.; Ottermanns, R.; Ratte, H.-T.

    2010-01-01

    Freshwater sediments with low levels of anthropogenic contamination and a broad range of geochemical properties were investigated using various sediment-contact tests in order to study the natural variability and to define toxicity thresholds for the various toxicity endpoints. Tests were performed with bacteria (Arthrobacter globiformis), yeast (Saccharomyces cerevisiae), nematodes (Caenorhabditis elegans), oligochaetes (Lumbriculus variegatus), higher plants (Myriophyllum aquaticum), and the eggs of zebrafish (Danio rerio). The variability in the response of some of the contact tests could be explained by particle size distribution and organic content. Only for two native sediments could a pollution effect not be excluded. Based on the minimal detectable difference (MDD) and the maximal tolerable inhibition (MTI), toxicity thresholds (% inhibition compared to the control) were derived for each toxicity parameter: >20% for plant growth and fish-egg survival, >25% for nematode growth and oligochaete reproduction, >50% for nematode reproduction and >60% for bacterial enzyme activity. - Sediment-contact tests require toxicity thresholds based on their variability in native sediments with low-level contamination.

  2. Diversity of cultivable bacteria involved in the formation of macroscopic microbial colonies (Cave silver on the walls of a cave in Slovenia

    Directory of Open Access Journals (Sweden)

    Blagajana Herzog Velikonja

    2014-01-01

    Full Text Available Karstic caves often support white, yellow, grey or pink microbial colonies that are termed ‘cave silver’ by speleologists. Using various sample pre-treatments and culture media, a wide variety of bacteria associated with these colonies were recovered from a cave in Slovenia, Pajsarjeva jama. Decreasing the inoculum size resulted in significant increases in viable counts, while pre-treatments had the opposite effect with the exception of microwave irradiation. While all growth media yielded viable counts, the maximal counts were observed on a low-nutrient TWA medium. Based on the 16S rRNA gene sequence of OTU representatives, the majority of the 80 isolates examined belonged to Streptomyces (25%, Micrococcus (16% and Rhodococcus (10% Other abundant groups were Pseudomonas (9%, Agrobacterium (8%, Lysobacter (6% and Paenibacillus (5%, while members of genera Microbacterium, Agrococcus, Arthrobacter, Bacillus, Kocuria, Oerskovia, Sphingomonas, Aerococcus, and Bosea represented a minor portion of cultivable diversity encountered. Members of Streptomyces and Agrobacterium were common to all samples. Although these microorganisms readily form colonies under laboratory conditions, they were unrelated to abundant environmental phylotypes recovered from same samples in a previous study. However, the comparative 16S rRNA analysis showed that microorganisms highly related to the ones obtained in this study were cultivated from other subterranean environments indicating that they might represent true microbial cave dwellers.

  3. Isolation of Endophytic Plant Growth-Promoting Bacteria Associated with the Halophyte Salicornia europaea and Evaluation of their Promoting Activity Under Salt Stress.

    Science.gov (United States)

    Zhao, Shuai; Zhou, Na; Zhao, Zheng-Yong; Zhang, Ke; Wu, Guo-Hua; Tian, Chang-Yan

    2016-10-01

    Several reports have highlighted that many plant growth-promoting endophytic bacteria (PGPE) can assist their host plants in coping with various biotic and abiotic stresses. However, information about the PGPE colonizing in the halophytes is still scarce. This study was designed to isolate and characterize PGPE from salt-accumulating halophyte Salicornia europaea grown under extreme salinity and to evaluate in vitro the bacterial mechanisms related to plant growth promotion. A total of 105 isolates were obtained from the surface-sterilized roots, stems, and assimilation twigs of S. europaea. Thirty-two isolates were initially selected for their ability to produce 1-aminocyclopropane-1-carboxylate deaminase as well as other properties such as production of indole-3-acetic acid and phosphate-solubilizing activities. The 16S rRNA gene-sequencing analysis revealed that these isolates belong to 13 different genera and 19 bacterial species. For these 32 strains, seed germination and seedling growth in axenically grown S. europaea seedlings at different NaCl concentrations (50-500 mM) were quantified. Five isolates possessing significant stimulation of the host plant growth were obtained. The five isolates were identified as Bacillus endophyticus, Bacillus tequilensis, Planococcus rifietoensis, Variovorax paradoxus, and Arthrobacter agilis. All the five strains could colonize and can be reisolated from the host plant interior tissues. These results demonstrate that habitat-adapted PGPE isolated from halophyte could enhance plant growth under saline stress conditions.

  4. Biodegradability of bacterial surfactants.

    Science.gov (United States)

    Lima, Tânia M S; Procópio, Lorena C; Brandão, Felipe D; Carvalho, André M X; Tótola, Marcos R; Borges, Arnaldo C

    2011-06-01

    This work aimed at evaluating the biodegradability of different bacterial surfactants in liquid medium and in soil microcosms. The biodegradability of biosurfactants by pure and mixed bacterial cultures was evaluated through CO(2) evolution. Three bacterial strains, Acinetobacter baumanni LBBMA ES11, Acinetobacter haemolyticus LBBMA 53 and Pseudomonas sp. LBBMA 101B, used the biosurfactants produced by Bacillus sp. LBBMA 111A (mixed lipopeptide), Bacillus subtilis LBBMA 155 (lipopeptide), Flavobacterium sp. LBBMA 168 (mixture of flavolipids), Dietzia Maris LBBMA 191(glycolipid) and Arthrobacter oxydans LBBMA 201(lipopeptide) as carbon sources in minimal medium. The synthetic surfactant sodium dodecyl sulfate (SDS) was also mineralized by these microorganisms, but at a lower rate. CO(2) emitted by a mixed bacterial culture in soil microcosms with biosurfactants was higher than in the microcosm containing SDS. Biosurfactant mineralization in soil was confirmed by the increase in surface tension of the soil aqueous extracts after incubation with the mixed bacterial culture. It can be concluded that, in terms of biodegradability and environmental security, these compounds are more suitable for applications in remediation technologies in comparison to synthetic surfactants. However, more information is needed on structure of biosurfactants, their interaction with soil and contaminants and scale up and cost for biosurfactant production.

  5. Phenanthrene and Pyrene Modify the Composition and Structure of the Cultivable Endophytic Bacterial Community in Ryegrass (Lolium multiflorum Lam

    Directory of Open Access Journals (Sweden)

    Xuezhu Zhu

    2016-11-01

    Full Text Available This study provides new insights into the dynamics of bacterial community structure during phytoremediation. The communities of cultivable autochthonous endophytic bacteria in ryegrass exposed to polycyclic aromatic hydrocarbons (PAHs were investigated with regard to their potential to biodegrade PAHs. Bacterial counts and 16S rRNA gene sequence were used in the microbiological evaluation. A total of 33 endophytic bacterial strains were isolated from ryegrass plants, which represented 15 different genera and eight different classes, respectively. Moreover, PAH contamination modified the composition and structure of the endophytic bacterial community in the plants. Bacillus sp., Pantoea sp., Pseudomonas sp., Arthrobacter sp., Pedobacter sp. and Delftia sp. were only isolated from the seedlings exposed to PAHs. Furthermore, the dominant genera in roots shifted from Enterobacter sp. to Serratia sp., Bacillus sp., Pantoea sp., and Stenotrophomonas sp., which could highly biodegrade phenanthrene (PHE. However, the diversity of endophytic bacterial community was decreased by exposure to the mixture of PAHs, and increased by respective exposure to PHE and pyrene (PYR, while the abundance was increased by PAH exposure. The results clearly indicated that the exposure of plants to PAHs would be beneficial for improving the effectiveness of phytoremediation of PAHs.

  6. Profiling microbial community structures across six large oilfields in China and the potential role of dominant microorganisms in bioremediation.

    Science.gov (United States)

    Sun, Weimin; Li, Jiwei; Jiang, Lei; Sun, Zhilei; Fu, Meiyan; Peng, Xiaotong

    2015-10-01

    Successful bioremediation of oil pollution is based on a comprehensive understanding of the in situ physicochemical conditions and indigenous microbial communities as well as the interaction between microorganisms and geochemical variables. Nineteen oil-contaminated soil samples and five uncontaminated controls were taken from six major oilfields across different geoclimatic regions in China to investigate the spatial distribution of the microbial ecosystem. Microbial community analysis revealed remarkable variation in microbial diversity between oil-contaminated soils taken from different oilfields. Canonical correspondence analysis (CCA) further demonstrated that a suite of in situ geochemical parameters, including soil moisture and sulfate concentrations, were among the factors that influenced the overall microbial community structure and composition. Phylogenetic analysis indicated that the vast majority of sequences were related to the genera Arthrobacter, Dietzia, Pseudomonas, Rhodococcus, and Marinobacter, many of which contain known oil-degrading or oil-emulsifying species. Remarkably, a number of archaeal genera including Halalkalicoccus, Natronomonas, Haloterrigena, and Natrinema were found in relatively high abundance in some of the oil-contaminated soil samples, indicating that these Euryarchaeota may play an important ecological role in some oil-contaminated soils. This study offers a direct and reliable reference of the diversity of the microbial community in various oil-contaminated soils and may influence strategies for in situ bioremediation of oil pollution.

  7. Microbial communities inhabiting oil-contaminated soils from two major oilfields in Northern China: Implications for active petroleum-degrading capacity.

    Science.gov (United States)

    Sun, Weimin; Dong, Yiran; Gao, Pin; Fu, Meiyan; Ta, Kaiwen; Li, Jiwei

    2015-06-01

    Although oilfields harbor a wide diversity of microorganisms with various metabolic potentials, our current knowledge about oil-degrading bacteria is limited because the vast majority of oil-degrading bacteria remain uncultured. In the present study, microbial communities in nine oil-contaminated soils collected from Daqing and Changqing, two of the largest oil fields in China, were characterized through highthroughput sequencing of 16S rRNA genes. Bacteria related to the phyla Proteobacteria and Actinobacteria were dominant in four and three samples, respectively. At the genus level, Alkanindiges, Arthrobacter, Pseudomonas, Mycobacterium, and Rhodococcus were frequently detected in nine soil samples. Many of the dominant genera were phylogenetically related to the known oil-degrading species. The correlation between physiochemical parameters within the microbial communities was also investigated. Canonical correspondence analysis revealed that soil moisture, nitrate, TOC, and pH had an important impact in shaping the microbial communities of the hydrocarbon-contaminated soil. This study provided an in-depth analysis of microbial communities in oilcontaminated soil and useful information for future bioremediation of oil contamination.

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

    Science.gov (United States)

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

    2018-05-01

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

  9. Crude Oil Treatment Leads to Shift of Bacterial Communities in Soils from the Deep Active Layer and Upper Permafrost along the China-Russia Crude Oil Pipeline Route

    Science.gov (United States)

    Yang, Sizhong; Wen, Xi; Zhao, Liang; Shi, Yulan; Jin, Huijun

    2014-01-01

    The buried China-Russia Crude Oil Pipeline (CRCOP) across the permafrost-associated cold ecosystem in northeastern China carries a risk of contamination to the deep active layers and upper permafrost in case of accidental rupture of the embedded pipeline or migration of oil spills. As many soil microbes are capable of degrading petroleum, knowledge about the intrinsic degraders and the microbial dynamics in the deep subsurface could extend our understanding of the application of in-situ bioremediation. In this study, an experiment was conducted to investigate the bacterial communities in response to simulated contamination to deep soil samples by using 454 pyrosequencing amplicons. The result showed that bacterial diversity was reduced after 8-weeks contamination. A shift in bacterial community composition was apparent in crude oil-amended soils with Proteobacteria (esp. α-subdivision) being the dominant phylum, together with Actinobacteria and Firmicutes. The contamination led to enrichment of indigenous bacterial taxa like Novosphingobium, Sphingobium, Caulobacter, Phenylobacterium, Alicylobacillus and Arthrobacter, which are generally capable of degrading polycyclic aromatic hydrocarbons (PAHs). The community shift highlighted the resilience of PAH degraders and their potential for in-situ degradation of crude oil under favorable conditions in the deep soils. PMID:24794099

  10. Scanning electron and light microscopic study of microbial succession on bethlehem st. Nectaire cheese.

    Science.gov (United States)

    Marcellino, S N; Benson, D R

    1992-11-01

    St. Nectaire cheese is a semisoft cheese of French origin that, along with Brie and Camembert cheeses, belongs to the class of surface mold-ripened cheese. The surface microorganisms that develop on the cheese rind during ripening impart a distinctive aroma and flavor to this class of cheese. We have documented the sequential appearance of microorganisms on the cheese rind and in the curd over a 60-day ripening period. Scanning electron microscopy was used to visualize the development of surface fungi and bacteria. Light microscopy of stained paraffin sections was used to study cross sections through the rind. We also monitored the development of bacterial and yeast populations in and the pH of the curd and rind. The earliest stage of ripening (0 to 2 days) is dominated by the lactic acid bacterium Streptococcus cremoris and multilateral budding yeasts, primarily Debaryomyces and Torulopsis species. Geotrichum candidum follows closely, and then zygomycetes of the genus Mucor develop at day 4 of ripening. At day 20, the deuteromycete Trichothecium roseum appears. From day 20 until the end of the ripening process, coryneforms of the genera Brevibacterium and Arthrobacter can be seen near the surface of the cheese rind among fungal hyphae and yeast cells.

  11. Variability of sediment-contact tests in freshwater sediments with low-level anthropogenic contamination - Determination of toxicity thresholds

    Energy Technology Data Exchange (ETDEWEB)

    Hoess, S., E-mail: hoess@ecossa.d [Ecossa, Giselastr. 6, 82319 Starnberg (Germany); Institute of Biodiversity - Network (IBN), Dreikronengasse 2, 93047 Regensburg (Germany); Ahlf, W., E-mail: ahlf@tu-harburg.d [Institute of Environmental Technology and Energy Economics, Technical University Hamburg-Harburg, Eissendorfer Str. 40, 21071 Hamburg (Germany); Fahnenstich, C. [Institute of Environmental Technology and Energy Economics, Technical University Hamburg-Harburg, Eissendorfer Str. 40, 21071 Hamburg (Germany); Gilberg, D., E-mail: d-gilberg@ect.d [ECT Oekotoxikologie, Boettgerstr. 2-14, 65439 Floersheim (Germany); Hollert, H., E-mail: henner.hollert@bio5.rwth-aachen.d [Department of Ecosystem Analysis, Institute for Environmental Research (Biology 5), RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); Melbye, K. [Dr. Fintelmann and Dr. Meyer, Mendelssohnstr. 15D, 22761 Hamburg (Germany); Meller, M., E-mail: m-meller@ecotox-consult.d [ECT Oekotoxikologie, Boettgerstr. 2-14, 65439 Floersheim (Germany); Hammers-Wirtz, M., E-mail: hammers-wirtz@gaiac.rwth-aachen.d [Research Institute for Ecosystem Analysis and Assessment (gaiac), RWTH Aachen University, Worringerweg 1, 52056 Aachen (Germany); Heininger, P., E-mail: heininger@bafg.d [Federal Institute of Hydrology (BfG), Am Mainzer Tor 1, 56070 Koblenz (Germany); Neumann-Hensel, H., E-mail: hensel@fintelmann-meyer.d [Dr. Fintelmann and Dr. Meyer, Mendelssohnstr. 15D, 22761 Hamburg (Germany); Ottermanns, R., E-mail: ottermanns@bio5.rwth-aachen.d [Chair for Environmental Biology and Chemodynamics, Institute for Environmental Research (Biology 5), RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany); Ratte, H.-T., E-mail: toni.ratte@bio5.rwth-aachen.d [Chair for Environmental Biology and Chemodynamics, Institute for Environmental Research (Biology 5), RWTH Aachen University, Worringerweg 1, 52074 Aachen (Germany)

    2010-09-15

    Freshwater sediments with low levels of anthropogenic contamination and a broad range of geochemical properties were investigated using various sediment-contact tests in order to study the natural variability and to define toxicity thresholds for the various toxicity endpoints. Tests were performed with bacteria (Arthrobacter globiformis), yeast (Saccharomyces cerevisiae), nematodes (Caenorhabditis elegans), oligochaetes (Lumbriculus variegatus), higher plants (Myriophyllum aquaticum), and the eggs of zebrafish (Danio rerio). The variability in the response of some of the contact tests could be explained by particle size distribution and organic content. Only for two native sediments could a pollution effect not be excluded. Based on the minimal detectable difference (MDD) and the maximal tolerable inhibition (MTI), toxicity thresholds (% inhibition compared to the control) were derived for each toxicity parameter: >20% for plant growth and fish-egg survival, >25% for nematode growth and oligochaete reproduction, >50% for nematode reproduction and >60% for bacterial enzyme activity. - Sediment-contact tests require toxicity thresholds based on their variability in native sediments with low-level contamination.

  12. MICROBIOTA OF PINUS POLLEN AS ADJUVANT FACTOR OF ALLERGY

    Directory of Open Access Journals (Sweden)

    Tetiana Shevtsova

    2016-06-01

    Full Text Available Bacteria, their endotoxin and mold found on pollen can be a reason of respiratory symptoms in sensitized individuals. This question concerns an anemophilous pollen more acute. In this work quantitative by dilution plating method and qualitative microbial analysis by MALDI-TOF MS Biotyper of pollen and other plants organs of Pinus sylvestris L., P. nigra Arnold, P. mugo Turra, P. armandii Franch., P. wallichiana A.B. Jacks from Nitra, Slovakia are performed which shows quantitative and species differences in mesophilic aerobic (0.00-6.27 log cfu/g and anaerobic bacteria (0.00-3.70 log cfu/g, enterococci (0.00 log cfu/g, coliform bacteria (0.00-5.29 log cfu/g, lactobacilli (0.00-4.20 log cfu/g, microscopic fungi and yeasts (2.60-5.29 log cfu/g content. Representatives of Pseudomonas (14, Bacillus (2, Acinetobacter (1, Arthrobacter (1, Pantoea (1, Klebsiella (1, Penicillium (6, Aspergillus (4, Cladosporium (1, Debaryomyces (1 genera were revealed on pine trees. The allergenic potential of the identified association of microorganisms on pollen has been evaluated based on published data. The results may be useful for aerobiologists, allergists and microbiologists, at least at the local level.

  13. Effect of salt-tolerant plant growth-promoting rhizobacteria on wheat plants and soil health in a saline environment.

    Science.gov (United States)

    Upadhyay, S K; Singh, D P

    2015-01-01

    Salt-tolerant plant growth-promoting rhizobacteria (ST-PGPR) significantly influence the growth and yield of wheat crops in saline soil. Wheat growth improved in pots with inoculation of all nine ST-PGPR (ECe = 4.3 dS·m(-1) ; greenhouse experiment), while maximum growth and dry biomass was observed in isolate SU18 Arthrobacter sp.; simultaneously, all ST-PGPR improved soil health in treated pot soil over controls. In the field experiment, maximum wheat root dry weight and shoot biomass was observed after inoculation with SU44 B. aquimaris, and SU8 B. aquimaris, respectively, after 60 and 90 days. Isolate SU8 B. aquimaris, induced significantly higher proline and total soluble sugar accumulation in wheat, while isolate SU44 B. aquimaris, resulted in higher accumulation of reducing sugars after 60 days. Percentage nitrogen (N), potassium (K) and phosphorus (P) in leaves of wheat increased significantly after inoculation with ST-PGPR, as compared to un-inoculated plants. Isolate SU47 B. subtilis showed maximum reduction of sodium (Na) content in wheat leaves of about 23% at both 60 and 90 days after sowing, and produced the best yield of around 17.8% more than the control. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.

  14. The examination of radiological monitoring on Okayama Prefectural Institute for Environmental Science and Public Health

    Energy Technology Data Exchange (ETDEWEB)

    Kanematsu, Seiko [Okayama Prefectural Inst. for Environmental Science and Public Health (Japan)

    2000-09-01

    We evaluated the environment around Ningyotoge in the northern part of Okayama Prefecture. Environmental gamma ray measurement results were evaluated by TLD at the time of confirming an investigation using a continuous gamma ray monitor. Doses during that time span for passing persons and individuals in the area were lower than 89 nGy/h. We observed Fading for TLD. The result was that the Fading revision coefficient for the Tenno district in Ningyotoge between October 10, 1997 to December 18, 1997 was 1.02. That for the premises of the Okayama Prefectural Institute for Environmental Science and Public Health was 1.05. The Tenno district in Ningyotoge during the period between June 29, 1998 to October 6, 1998 was 1.04. A relationship between the height from the ground and gamma ray dose was found. A straight line was shown by both logarithm graphs. We evaluated radioactive wastewater. When considering the processing of wastewater that flows into rivers, a discharge of zero release is desirable. We evaluated the BOD, COD, etc, as well as the radioactive materials that are processed by microbes such as Bacillus and Arthrobacter. (author)

  15. Toxicity evaluation of textile effluents and role of native soil bacterium in biodegradation of a textile dye.

    Science.gov (United States)

    Khan, Sana; Malik, Abdul

    2018-02-01

    Water pollution caused by the discharge of hazardous textile effluents is a serious environmental problem worldwide. In order to assess the pollution level of the textile effluents, various physico-chemical parameters were analyzed in the textile wastewater and agricultural soil irrigated with the wastewater (contaminated soil) using atomic absorption spectrophotometer and gas chromatography-mass spectrometry (GC-MS) analysis that demonstrated the presence of several toxic heavy metals (Ni, Cu, Cr, Pb, Cd, and Zn) and a large number of organic compounds. Further, in order to get a comprehensive idea about the toxicity exerted by the textile effluent, mung bean seed germination test was performed that indicated the reduction in percent seed germination and radicle-plumule growth. The culturable microbial populations were also enumerated and found to be significantly lower in the wastewater and contaminated soil than the ground water irrigated soil, thus indicating the biotic homogenization of indigenous microflora. Therefore, the study was aimed to develop a cost effective and ecofriendly method of textile waste treatment using native soil bacterium, identified as Arthrobacter soli BS5 by 16S rDNA sequencing that showed remarkable ability to degrade a textile dye reactive black 5 with maximum degradation of 98% at 37 °C and pH in the range of 5-9 after 120 h of incubation.

  16. PA0148 from Pseudomonas aeruginosa Catalyzes the Deamination of Adenine

    Energy Technology Data Exchange (ETDEWEB)

    Goble, A.M.; Swaminathan, S.; Zhang, Z.; Sauder, J. M.; Burley, S. K.; Raushel, F. M.

    2011-08-02

    Four proteins from NCBI cog1816, previously annotated as adenosine deaminases, have been subjected to structural and functional characterization. Pa0148 (Pseudomonas aeruginosa PAO1), AAur1117 (Arthrobacter aurescens TC1), Sgx9403e, and Sgx9403g have been purified and their substrate profiles determined. Adenosine is not a substrate for any of these enzymes. All of these proteins will deaminate adenine to produce hypoxanthine with k{sub cat}/K{sub m} values that exceed 10{sup 5} M{sup -1} s{sup -1}. These enzymes will also accept 6-chloropurine, 6-methoxypurine, N-6-methyladenine, and 2,6-diaminopurine as alternate substrates. X-ray structures of Pa0148 and AAur1117 have been determined and reveal nearly identical distorted ({beta}/{alpha}){sub 8} barrels with a single zinc ion that is characteristic of members of the amidohydrolase superfamily. Structures of Pa0148 with adenine, 6-chloropurine, and hypoxanthine were also determined, thereby permitting identification of the residues responsible for coordinating the substrate and product.

  17. High-throughput sequencing of microbial community diversity in soil, grapes, leaves, grape juice and wine of grapevine from China

    Science.gov (United States)

    Yan, Yin-zhuo; Zou, Wan; Ma, Wen-rui; Wang, Wei; Tian, Ge; Wang, Li-ye

    2018-01-01

    In this study Illumina MiSeq was performed to investigate microbial diversity in soil, leaves, grape, grape juice and wine. A total of 1,043,102 fungal Internal Transcribed Spacer (ITS) reads and 2,422,188 high quality bacterial 16S rDNA sequences were used for taxonomic classification, revealed five fungal and eight bacterial phyla. At the genus level, the dominant fungi were Ascomycota, Sordariales, Tetracladium and Geomyces in soil, Aureobasidium and Pleosporaceae in grapes leaves, Aureobasidium in grape and grape juice. The dominant bacteria were Kaistobacter, Arthrobacter, Skermanella and Sphingomonas in soil, Pseudomonas, Acinetobacter and Kaistobacter in grape and grapes leaves, and Oenococcus in grape juice and wine. Principal coordinate analysis showed structural separation between the composition of fungi and bacteria in all samples. This is the first study to understand microbiome population in soil, grape, grapes leaves, grape juice and wine in Xinjiang through High-throughput Sequencing and identify microorganisms like Saccharomyces cerevisiae and Oenococcus spp. that may contribute to the quality and flavor of wine. PMID:29565999

  18. Topographical Mapping of the Rainbow Trout (Oncorhynchus mykiss) Microbiome Reveals a Diverse Bacterial Community with Antifungal Properties in the Skin

    Science.gov (United States)

    Lowrey, Liam; Woodhams, Douglas C.; Tacchi, Luca

    2015-01-01

    The mucosal surfaces of wild and farmed aquatic vertebrates face the threat of many aquatic pathogens, including fungi. These surfaces are colonized by diverse symbiotic bacterial communities that may contribute to fight infection. Whereas the gut microbiome of teleosts has been extensively studied using pyrosequencing, this tool has rarely been employed to study the compositions of the bacterial communities present on other teleost mucosal surfaces. Here we provide a topographical map of the mucosal microbiome of an aquatic vertebrate, the rainbow trout (Oncorhynchus mykiss). Using 16S rRNA pyrosequencing, we revealed novel bacterial diversity at each of the five body sites sampled and showed that body site is a strong predictor of community composition. The skin exhibited the highest diversity, followed by the olfactory organ, gills, and gut. Flectobacillus was highly represented within skin and gill communities. Principal coordinate analysis and plots revealed clustering of external sites apart from internal sites. A highly diverse community was present within the epithelium, as demonstrated by confocal microscopy and pyrosequencing. Using in vitro assays, we demonstrated that two Arthrobacter sp. skin isolates, a Psychrobacter sp. strain, and a combined skin aerobic bacterial sample inhibit the growth of Saprolegnia australis and Mucor hiemalis, two important aquatic fungal pathogens. These results underscore the importance of symbiotic bacterial communities of fish and their potential role for the control of aquatic fungal diseases. PMID:26209676

  19. Bioluminescent bioreporter sensing of foodborne toxins

    Science.gov (United States)

    Fraley, Amanda C.; Ripp, Steven; Sayler, Gary S.

    2004-06-01

    Histamine is the primary etiological agent in the foodborne disease scombrotoxicosis, one of the most common food toxicities related to fish consumption. Procedures for detecting histamine in fish products are available, but are often too expensive or too complex for routine use. As an alternative, a bacterial bioluminescent bioreporter has been constructed to develop a biosensor system that autonomously responds to low levels of histamine. The bioreporter contains a promoterless Photorhabdus luminescens lux operon (luxCDABE) fused with the Vibrio anguillarum angR regulatory gene promoter of the anguibactin biosynthetic operon. The bioreporter emitted 1.46 times more bioluminescence than background, 30 minutes after the addition of 100mM histamine. However, specificity was not optimal, as this biosensor generated significant bioluminescence in the presence of L-proline and L-histidine. As a means towards improving histamine specificity, the promoter region of a histamine oxidase gene from Arthrobacter globiformis was cloned upstream of the promotorless lux operon from Photorhabdus luminescens. This recently constructed whole-cell, lux-based bioluminescent bioreporter is currently being tested for optimal performance in the presence of histamine in order to provide a rapid, simple, and inexpensive model sensor for the detection of foodborne toxins.

  20. Distribution of bacteria in frozen shrimps and their decontamination by gamma irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Hitoshi; Adulyatham, P.; Ishigaki, Isao

    1987-11-01

    Six samples of frozen shrimps were obtained through importing company mainly from South-east Asian countries. Five samples of frozen shrimps contained 1.5 x 10/sup 5/ to 6.2 x 10/sup 6/ per gram of total aerobic bacteria, and 4 samples contained 1.4 x 10/sup 2/ to 2.2 x 10/sup 3/ per gram of coliforms, which are higher contamination than Japanese standard of hygenic level for frozen food products (total counts below 10/sup 5/ per gram and no coliforms). The dominant bacteria in total counts were consisted with psychrotrophic Moraxella, Arthrobacter, Micrococcus, Acinetobacter, Flavobacterium, Corynebacterium, Pseudomonas and etc, in all kinds of frozen shrimps. Salmonellae or enteric Vibrio were could not isolated by ordinary isolation methods, and there were isolated many strains of Proteus mirabilis instead of these bacteria. Necessary dose of gamma irradiation for decontamination of bacteria to hygenic level was decided as 3 approx. 5 kGy from the inactivation curves of total bacteria, coliforms, Proteus mirabilis and Salmonella typhymurium in frozen shrimps. Off-odor was suppressed by frozen condition of irradiation.

  1. Distribution of bacteria in frozen shrimps and their decontamination by gamma irradiation

    International Nuclear Information System (INIS)

    Ito, Hitoshi; Adulyatham, P.; Ishigaki, Isao

    1987-01-01

    Six samples of frozen shrimps were obtained through importing company mainly from South-east Asian countries. Five samples of frozen shrimps contained 1.5 x 10 5 to 6.2 x 10 6 per gram of total aerobic bacteria, and 4 samples contained 1.4 x 10 2 to 2.2 x 10 3 per gram of coliforms, which are higher contamination than Japanese standard of hygenic level for frozen food products (total counts below 10 5 per gram and no coliforms). The dominant bacteria in total counts were consisted with psychrotrophic Moraxella, Arthrobacter, Micrococcus, Acinetobacter, Flavobacterium, Corynebacterium, Pseudomonas and etc, in all kinds of frozen shrimps. Salmonellae or enteric Vibrio were could not isolated by ordinary isolation methods, and there were isolated many strains of Proteus mirabilis instead of these bacteria. Necessary dose of gamma irradiation for decontamination of bacteria to hygenic level was decided as 3 ∼ 5 kGy from the inactivation curves of total bacteria, coliforms, Proteus mirabilis and Salmonella typhymurium in frozen shrimps. Off-odor was suppressed by frozen condition of irradiation. (author)

  2. Diversity of pigmented Gram-positive bacteria associated with marine macroalgae from Antarctica.

    Science.gov (United States)

    Leiva, Sergio; Alvarado, Pamela; Huang, Ying; Wang, Jian; Garrido, Ignacio

    2015-12-01

    Little is known about the diversity and roles of Gram-positive and pigmented bacteria in Antarctic environments, especially those associated with marine macroorganisms. This work is the first study about the diversity and antimicrobial activity of culturable pigmented Gram-positive bacteria associated with marine Antarctic macroalgae. A total of 31 pigmented Gram-positive strains were isolated from the surface of six species of macroalgae collected in the King George Island, South Shetland Islands. On the basis of 16S rRNA gene sequence similarities ≥99%, 18 phylotypes were defined, which were clustered into 11 genera of Actinobacteria (Agrococcus, Arthrobacter, Brachybacterium, Citricoccus, Kocuria, Labedella, Microbacterium, Micrococcus, Rhodococcus, Salinibacterium and Sanguibacter) and one genus of the Firmicutes (Staphylococcus). It was found that five isolates displayed antimicrobial activity against a set of macroalgae-associated bacteria. The active isolates were phylogenetically related to Agrococcus baldri, Brachybacterium rhamnosum, Citricoccus zhacaiensis and Kocuria palustris. The results indicate that a diverse community of pigmented Gram-positive bacteria is associated with Antartic macroalgae and suggest its potential as a promising source of antimicrobial and pigmented natural compounds. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  3. Structure of choline oxidase in complex with the reaction product glycine betaine.

    Science.gov (United States)

    Salvi, Francesca; Wang, Yuan-Fang; Weber, Irene T; Gadda, Giovanni

    2014-02-01

    Choline oxidase from Arthrobacter globiformis, which is involved in the biosynthesis of glycine betaine from choline, has been extensively characterized in its mechanistic and structural properties. Despite the knowledge gained on the enzyme, the details of substrate access to the active site are not fully understood. The `loop-and-lid' mechanism described for the glucose-methanol-choline enzyme superfamily has not been confirmed for choline oxidase. Instead, a hydrophobic cluster on the solvent-accessible surface of the enzyme has been proposed by molecular dynamics to control substrate access to the active site. Here, the crystal structure of the enzyme was solved in complex with glycine betaine at pH 6.0 at 1.95 Å resolution, allowing a structural description of the ligand-enzyme interactions in the active site. This structure is the first of choline oxidase in complex with a physiologically relevant ligand. The protein structures with and without ligand are virtually identical, with the exception of a loop at the dimer interface, which assumes two distinct conformations. The different conformations of loop 250-255 define different accessibilities of the proposed active-site entrance delimited by the hydrophobic cluster on the other subunit of the dimer, suggesting a role in regulating substrate access to the active site.

  4. Biodegradation of nicotine by a novel nicotine-degrading bacterium, Pseudomonas plecoglossicida TND35 and its new biotransformation intermediates.

    Science.gov (United States)

    Raman, Gurusamy; Mohan, KasiNadar; Manohar, Venkat; Sakthivel, Natarajan

    2014-02-01

    Tobacco wastes that contain nicotine alkaloids are harmful to human health and the environment. In the investigation, a novel nicotine-biodegrading bacterium TND35 was isolated and identified as Pseudomonas plecoglossicida on the basis of phenotypic, biochemical characteristics and 16S rRNA sequence homology. We have studied the nicotine biodegradation potential of strain TND35 by detecting the intermediate metabolites using an array of approaches such as HPLC, GC-MS, NMR and FT-IR. Biotransformation metabolites, N-methylmyosmine, 4-hydroxy-1-(3-pyridyl)-1-butanone (HPB) and other three new intermediate metabolites namely, 3,5-bis (1-methylpyrrolidin-2-yl) pyridine, 2,3-dihydro-1-methyl-5-(pyridin-3-yl)-1H-pyrrol-2-ol and 5-(pyridin-3-yl)-1H-pyrrol-2(3H)-one have been identified. Interestingly, these intermediate metabolites suggest that the strain TND35 employs a novel nicotine biodegradation pathway, which is different from the reported pathways of Aspergillus oryzae 112822, Arthrobacter nicotinovorans pAO1, Agrobacterium tumefaciens S33 and other species of Pseudomonas. The metabolite, HPB reported in this study can also be used as biochemical marker for tobacco related cancer studies.

  5. Diversity, ecological distribution and biotechnological potential of Actinobacteria inhabiting seamounts and non-seamounts in the Tyrrhenian Sea

    KAUST Repository

    Ettoumi, Besma

    2016-04-01

    In the present study, the ecological distribution of marine Actinobacteria isolated from seamount and non-seamount stations in the Tyrrhenian Sea was investigated. A collection of 110 isolates was analyzed by Automated Ribosomal Intergenic Spacer Analysis (ARISA) and 16S rRNA gene sequencing of representatives for each ARISA haplotype (n = 49). Phylogenetic analysis of 16S rRNA sequences showed a wide diversity of marine isolates and clustered the strains into 11 different genera, Janibacter, Rhodococcus, Arthrobacter, Kocuria, Dietzia, Curtobacterium, Micrococcus, Citricoccus, Brevibacterium, Brachybacterium and Nocardioides. Interestingly, Janibacter limosus was the most encountered species particularly in seamounts stations, suggesting that it represents an endemic species of this particular ecosystem. The application of BOX-PCR fingerprinting on J. limosus sub-collection (n = 22), allowed their separation into seven distinct BOX-genotypes suggesting a high intraspecific microdiversity among the collection. Furthermore, by screening the biotechnological potential of selected actinobacterial strains, J. limosus was shown to exhibit the most important biosurfactant activity. Our overall data indicates that Janibacter is a major and active component of seamounts in the Tyrrhenian Sea adapted to low nutrient ecological niche.

  6. Recovery of metallo-tolerant and antibiotic resistant psychrophilic bacteria from Siachen glacier, Pakistan.

    Directory of Open Access Journals (Sweden)

    Muhammad Rafiq

    Full Text Available Cultureable bacterial diversity of previously unexplored Siachen glacier, Pakistan, was studied. Out of 50 isolates 33 (66% were Gram negative and 17 (34% Gram positive. About half of the isolates were pigment producers and were able to grow at 4-37°C. 16S rRNA gene sequences revealed Gram negative bacteria dominated by Proteobacteria (especially γ-proteobacteria and β-proteobacteria and Flavobacteria. The genus Pseudomonas (51.51%, 17 was dominant among γ- proteobacteria. β-proteobacteria constituted 4 (12.12% Alcaligenes and 4 (12.12% Janthinobacterium strains. Among Gram positive bacteria, phylum Actinobacteria, Rhodococcus (23.52%, 4 and Arthrobacter (23.52%, 4 were the dominating genra. Other bacteria belonged to Phylum Firmicutes with representative genus Carnobacterium (11.76%, 2 and 4 isolates represented 4 genera Bacillus, Lysinibacillus, Staphylococcus and Planomicrobium. Most of the Gram negative bacteria were moderate halophiles, while most of the Gram positives were extreme halophiles and were able to grow up to 6.12 M of NaCl. More than 2/3 of the isolates showed antimicrobial activity against multidrug resistant S. aureus, E. coli, Klebsiella pneumonia, Enterococcus faecium, Candida albicans, Aspergillus flavus and Aspergillus fumigatus and ATCC strains. Gram positive bacteria (94.11% were more resistant to heavy metals as compared to Gram negative (78.79% and showed maximum tolerance against iron and least tolerance against mercury.

  7. Diversity, ecological distribution and biotechnological potential of Actinobacteria inhabiting seamounts and non-seamounts in the Tyrrhenian Sea.

    Science.gov (United States)

    Ettoumi, Besma; Chouchane, Habib; Guesmi, Amel; Mahjoubi, Mouna; Brusetti, Lorenzo; Neifar, Mohamed; Borin, Sara; Daffonchio, Daniele; Cherif, Ameur

    2016-01-01

    In the present study, the ecological distribution of marine Actinobacteria isolated from seamount and non-seamount stations in the Tyrrhenian Sea was investigated. A collection of 110 isolates was analyzed by Automated Ribosomal Intergenic Spacer Analysis (ARISA) and 16S rRNA gene sequencing of representatives for each ARISA haplotype (n=49). Phylogenetic analysis of 16S rRNA sequences showed a wide diversity of marine isolates and clustered the strains into 11 different genera, Janibacter, Rhodococcus, Arthrobacter, Kocuria, Dietzia, Curtobacterium, Micrococcus, Citricoccus, Brevibacterium, Brachybacterium and Nocardioides. Interestingly, Janibacter limosus was the most encountered species particularly in seamounts stations, suggesting that it represents an endemic species of this particular ecosystem. The application of BOX-PCR fingerprinting on J. limosus sub-collection (n=22), allowed their separation into seven distinct BOX-genotypes suggesting a high intraspecific microdiversity among the collection. Furthermore, by screening the biotechnological potential of selected actinobacterial strains, J. limosus was shown to exhibit the most important biosurfactant activity. Our overall data indicates that Janibacter is a major and active component of seamounts in the Tyrrhenian Sea adapted to low nutrient ecological niche. Copyright © 2016 Elsevier GmbH. All rights reserved.

  8. [Isolation methods and diversity of culturable fecal actinobacteria associated with Panthera tigris tigris in Yunnan Safari Park].

    Science.gov (United States)

    Cao, Yanru; Jiang, Yi; Li, Youlong; Chen, Xiu; Jin, Rongxian; He, Wenxiang

    2012-07-04

    We studied the isolation methods and diversity of culturable fecal actinobacteria associated with Panthera tigris tigris by using culture-dependent approaches. Fresh fecal samples of healthy Panthera tigris tigris were collected from Yunnan Safari Park. Pretreatment of the samples, isolation media and inhibitors were tested for actinobacteria isolation. 16S rRNA genes of actinobacteria were sequenced and subjected to phylogenetic analysis. The abundance of culturable actinobacteria was 1.10 x 10(8) cfu/g colony forming units (CFU) per gram of feces (wet weight). We obtained 110 purified cultural actinobacterium strains. The analysis based on 16S rRNA gene sequences showed that these strains were distributed in 10 different families and 12 genera of actinobacteria at least, and most of them were non-filamentous, such as Arthrobacter, Dietzia, Kocuria, Corynebacterium and Microbacterium. Streptomyces was the mainly classical filamentous actinobacteria, and up to 64% of total. Drying and heating up the fecal samples can greatly increase the rate of the actinobacteria. Many kinds of inhibitors and chemical defined media are suitable for isolation of fecal actinobacteria. The culturable actinobacteria are abundant in Panthera tigris tigris feces. Our study found an effective method to isolate animals' fecal actinobacteria and it's useful for studying and exploiting animals' fecal actinobacteria.

  9. Brazilian Cerrado soil Actinobacteria ecology.

    Science.gov (United States)

    Suela Silva, Monique; Naves Sales, Alenir; Teixeira Magalhães-Guedes, Karina; Ribeiro Dias, Disney; Schwan, Rosane Freitas

    2013-01-01

    A total of 2152 Actinobacteria strains were isolated from native Cerrado (Brazilian Savannah) soils located in Passos, Luminárias, and Arcos municipalities (Minas Gerais State, Brazil). The soils were characterised for chemical and microbiological analysis. The microbial analysis led to the identification of nine genera (Streptomyces, Arthrobacter, Rhodococcus, Amycolatopsis, Microbacterium, Frankia, Leifsonia, Nakamurella, and Kitasatospora) and 92 distinct species in both seasons studied (rainy and dry). The rainy season produced a high microbial population of all the aforementioned genera. The pH values of the soil samples from the Passos, Luminárias, and Arcos regions varied from 4.1 to 5.5. There were no significant differences in the concentrations of phosphorus, magnesium, and organic matter in the soils among the studied areas. Samples from the Arcos area contained large amounts of aluminium in the rainy season and both hydrogen and aluminium in the rainy and dry seasons. The Actinobacteria population seemed to be unaffected by the high levels of aluminium in the soil. Studies are being conducted to produce bioactive compounds from Actinobacteria fermentations on different substrates. The present data suggest that the number and diversity of Actinobacteria spp. in tropical soils represent a vast unexplored resource for the biotechnology of bioactives production.

  10. Endophytic Actinobacteria Associated with Dracaena cochinchinensis Lour.: Isolation, Diversity, and Their Cytotoxic Activities.

    Science.gov (United States)

    Salam, Nimaichand; Khieu, Thi-Nhan; Liu, Min-Jiao; Vu, Thu-Trang; Chu-Ky, Son; Quach, Ngoc-Tung; Phi, Quyet-Tien; Narsing Rao, Manik Prabhu; Fontana, Angélique; Sarter, Samira; Li, Wen-Jun

    2017-01-01

    Dracaena cochinchinensis Lour. is an ethnomedicinally important plant used in traditional Chinese medicine known as dragon's blood. Excessive utilization of the plant for extraction of dragon's blood had resulted in the destruction of the important niche. During a study to provide a sustainable way of utilizing the resources, the endophytic Actinobacteria associated with the plant were explored for potential utilization of their medicinal properties. Three hundred and four endophytic Actinobacteria belonging to the genera Streptomyces , Nocardiopsis , Brevibacterium , Microbacterium , Tsukamurella , Arthrobacter , Brachybacterium , Nocardia , Rhodococcus , Kocuria , Nocardioides , and Pseudonocardia were isolated from different tissues of D. cochinchinensis Lour. Of these, 17 strains having antimicrobial and anthracyclines-producing activities were further selected for screening of antifungal and cytotoxic activities against two human cancer cell lines, MCF-7 and Hep G2. Ten of these selected endophytic Actinobacteria showed antifungal activities against at least one of the fungal pathogens, of which three strains exhibited cytotoxic activities with IC 50 -values ranging between 3 and 33  μ g·mL -1 . Frequencies for the presence of biosynthetic genes, polyketide synthase- (PKS-) I, PKS-II, and nonribosomal peptide synthetase (NRPS) among these 17 selected bioactive Actinobacteria were 29.4%, 70.6%, and 23.5%, respectively. The results indicated that the medicinal plant D. cochinchinensis Lour. is a good niche of biologically important metabolites-producing Actinobacteria.

  11. Actinobacterial diversity in limestone deposit sites in Hundung, Manipur (India and their antimicrobial activities

    Directory of Open Access Journals (Sweden)

    Salam eNimaichand

    2015-05-01

    Full Text Available Studies on actinobacterial diversity in limestone habitats are scarce. This paper reports profiling of actinobacteria isolated from Hundung limestone samples in Manipur, India using ARDRA as the molecular tool for preliminary classification. A total of 137 actinobacteria were clustered into 31 phylotypic groups based on the ARDRA pattern generated and representative of each group was subjected to 16S rRNA gene sequencing. Generic diversity of the limestone isolates consisted of Streptomyces (15 phylotypic groups, Micromonospora (4, Amycolatopsis (3, Arthrobacter (3, Kitasatospora (2, Janibacter (1, Nocardia (1, Pseudonocardia (1 and Rhodococcus (1. Considering the antimicrobial potential of these actinobacteria, 19 showed antimicrobial activities against at least one of the bacterial and candidal test pathogens, while 45 exhibit biocontrol activities against at least one of the rice fungal pathogens. Out of the 137 actinobacterial isolates, 118 were found to have at least one of the three biosynthetic gene clusters (PKS-I, PKS-II, NRPS. The results indicate that 86% of the strains isolated from Hundung limestone deposit sites possessed biosynthetic gene clusters of which 40% exhibited antimicrobial activities. It can, therefore, be concluded that limestone habitat is a promising source for search of novel secondary metabolites.

  12. Brazilian Cerrado Soil Actinobacteria Ecology

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    Monique Suela Silva

    2013-01-01

    Full Text Available A total of 2152 Actinobacteria strains were isolated from native Cerrado (Brazilian Savannah soils located in Passos, Luminárias, and Arcos municipalities (Minas Gerais State, Brazil. The soils were characterised for chemical and microbiological analysis. The microbial analysis led to the identification of nine genera (Streptomyces, Arthrobacter, Rhodococcus, Amycolatopsis, Microbacterium, Frankia, Leifsonia, Nakamurella, and Kitasatospora and 92 distinct species in both seasons studied (rainy and dry. The rainy season produced a high microbial population of all the aforementioned genera. The pH values of the soil samples from the Passos, Luminárias, and Arcos regions varied from 4.1 to 5.5. There were no significant differences in the concentrations of phosphorus, magnesium, and organic matter in the soils among the studied areas. Samples from the Arcos area contained large amounts of aluminium in the rainy season and both hydrogen and aluminium in the rainy and dry seasons. The Actinobacteria population seemed to be unaffected by the high levels of aluminium in the soil. Studies are being conducted to produce bioactive compounds from Actinobacteria fermentations on different substrates. The present data suggest that the number and diversity of Actinobacteria spp. in tropical soils represent a vast unexplored resource for the biotechnology of bioactives production.

  13. Characterization and in-vivo evaluation of potential probiotics of the bacterial flora within the water column of a healthy shrimp larviculture system

    Science.gov (United States)

    Xue, Ming; Liang, Huafang; He, Yaoyao; Wen, Chongqing

    2016-05-01

    A thorough understanding of the normal bacterial flora associated with shrimp larviculture systems contributes to probiotic screening and disease control. The bacterial community of the water column over a commercial Litopenaeus vannamei larval rearing run was characterized with both culture-dependent and culture-independent methods. A total of 27 phylotypes at the species level were isolated and identified based on 16S rDNA sequence analysis. Denaturing gradient gel electrophoresis (DGGE) analysis of the V3-V5 region of 16S rRNA genes showed a dynamic bacterial community with major changes occurred from stages zoea to mysis during the rearing run. The sequences retrieved were affiliated to four phyla, Proteobacteria, Actinobacteria, Bacteroidetes, and Firmicutes, with the family Rhodobacteraceae being the most frequently recovered one. Subsequently, 13 representative strains conferred higher larval survival than the control when evaluated in the in-vivo experiments; in particular, three candidates, assigned to Phaeobacter sp., Arthrobacter sp., and Microbacterium sp., significantly improved larval survival ( P < 0.05). Therefore, the healthy shrimp larviculture system harbored a diverse and favorable bacterial flora, which contribute to larval development and are of great importance in exploiting novel probiotics.

  14. Direct evidence that ganglioside is an integral component of the thyrotropin receptor

    International Nuclear Information System (INIS)

    Kielczynski, W.; Harrison, L.C.; Leedman, P.J.

    1991-01-01

    Gangliosides were extracted from purified human and porcine thyrotropin (TSH) receptors (TSH-R) and were detected by probing with an 125 I-labeled sialic acid-specific lectin, Limax flavus agglutinin. Gangliosides copurified with human and porcine TSH-R migrated between monosialoganglioside GM1 and disialoganglioside GD1a. Ceramide glycanase digestion of the purified human TSH-R-associated glycolipid confirmed its ganglioside nature. It was resistant to Vibrio cholerae sialidase, which digest all gangliosides except GM1, but was sensitive to Arthrobacter ureafaciens sialidase, which digests all gangliosides including GM1. These findings indicate that the human TSH-R contains ganglioside that belongs to the galactosyl(β1→ 3)-N-acetylgalactosaminyl(β1→ 4)-[N-acetylneuraminyl(α2→ 3)]galactosyl(β1 → 4)glucosyl(β1 → 1)ceramide (GM1) family. Its intimate association with receptor protein implies a key role for ganglioside in the structure and function of the TSH-R

  15. Optimization of polysaccharides production by bacteria isolated from soil Otimização das condições de produção de polissacarídeos por bactérias isoladas do solo

    Directory of Open Access Journals (Sweden)

    Silvia Messias Bueno

    2006-09-01

    Full Text Available Six polysaccharide-producing bacteria, isolated from soil samples and identified as Pseudomonas and Arthrobacter (Strains 3B, 4B, 7B, 21B, 18E and 21D, were tested for the yield of polysaccharides produced during growth in two culture media: one containing glucose and the other sucrose (1, 2, 3, 4 and 5%. The yield was quantified measuring the viscosity of the broth, using the Poiscuille equation. The effect of temperature and pH of the culture media was investigated. The largest polysaccharide yield was obtained when the concentration of the carbon source was lower than 2%. Glucose and sucrose stimulated the polysaccharide production in a similar way. When the initial pH of the fermentation broth was increased from 5.0 up to 7.0, there was an increase in polysaccharide production. However, higher values (pH=8.0 caused a decrease in polysaccharide production. With regard to temperature, 30ºC was shown to be optimum, since higher or lower temperatures had a negative effect on saccharide production.Seis bactérias produtoras de polissacarídeos isoladas de amostras do solo (3B, 4B, 7B, 21B, 18E e 21D pertencentes aos gêneros Pseudomonas e Arthrobacter, foram testadas quanto ao rendimento da produção de polissacarídeos em dois caldos de cultura: um com glicose e outro com sacarose, nas concentrações de 1, 2, 3, 4 e 5%. O rendimento foi calculado medindo-se a viscosidade dos caldos, através da equação de Poiseuille. Também foi verificado o efeito da temperatura de incubação (25, 30 e 35ºC e o do pH (5, 6, 7 e 8 dos meios de cultura. Os resultados obtidos mostraram que concentrações da fonte de carbono até 2% apresentaram os maiores rendimentos do polissacarídeo. Glicose e sacarose estimularam a produção de polissacarídeos de forma similar. Quando o pH inicial do caldo de fermentação aumentou de 5,0 para 7,0 ocorreu um aumento da produção do polissacarídeo. Entretanto, valores mais altos (pH=8,0 causaram uma diminuição na

  16. Bacterial community of cushion plant Thylacospermum ceaspitosum on elevational gradient in the Himalayan cold desert.

    Science.gov (United States)

    Řeháková, Klára; Chroňáková, Alica; Krištůfek, Václav; Kuchtová, Barbora; Čapková, Kateřina; Scharfen, Josef; Čapek, Petr; Doležal, Jiří

    2015-01-01

    Although bacterial assemblages are important components of soils in arid ecosystems, the knowledge about composition, life-strategies, and environmental drivers is still fragmentary, especially in remote high-elevation mountains. We compared the quality and quantity of heterotrophic bacterial assemblages between the rhizosphere of the dominant cushion-forming plant Thylacospermum ceaspitosum and its surrounding bulk soil in two mountain ranges (East Karakoram: 4850-5250 m and Little Tibet: 5350-5850 m), in communities from cold steppes to the subnival zone in Ladakh, arid Trans-Himalaya, northwest India. Bacterial communities were characterized by molecular fingerprinting in combination with culture-dependent methods. The effects of environmental factors (elevation, mountain range, and soil physico-chemical parameters) on the bacterial community composition and structure were tested by multivariate redundancy analysis and conditional inference trees. Actinobacteria dominate the cultivable part of community and represent a major bacterial lineage of cold desert soils. The most abundant genera were Streptomyces, Arthrobacter, and Paenibacillus, representing both r- and K-strategists. The soil texture is the most important factor for the community structure and the total bacteria counts. Less abundant and diverse assemblages are found in East Karakoram with coarser soils derived from leucogranite bedrock, while more diverse assemblages in Little Tibet are associated with finer soils derived from easily weathering gneisses. Cushion rhizosphere is in general less diverse than bulk soil, and contains more r-strategists. K-strategists are more associated with the extremes of the gradient, with drought at lowest elevations (4850-5000 m) and frost at the highest elevations (5750-5850 m). The present study illuminates the composition of soil bacterial assemblages in relation to the cushion plant T. ceaspitosum in a xeric environment and brings important information about

  17. [Characterizing Beijing's Airborne Bacterial Communities in PM2.5 and PM1 Samples During Haze Pollution Episodes Using 16S rRNA Gene Analysis Method].

    Science.gov (United States)

    Wang, Bu-ying; Lang, Ji-dong; Zhang, Li-na; Fang, Jian-huo; Cao, Chen; Hao, Ji-ming; Zhu, Ting; Tian, Geng; Jiang, Jing-kun

    2015-08-01

    During 8th-14th Jan., 2013, severe particulate matter (PM) pollution episodes happened in Beijing. These air pollution events lead to high risks for public health. In addition to various PM chemical compositions, biological components in the air may also impose threaten. Little is known about airborne microbial community in such severe air pollution conditions. PM2.5 and PM10 samples were collected during that 7-day pollution period. The 16S rRNA gene V3 amplification and the MiSeq sequencing were performed for analyzing these samples. It is found that there is no significant difference at phylum level for PM2.5 bacterial communities during that 7-day pollution period both at phylum and at genus level. At genus level, Arthrobacter and Frankia are the major airborne microbes presented in Beijing winter.samples. At genus level, there are 39 common genera (combined by first 50 genera bacterial of the two analysis) between the 16S rRNA gene analysis and those are found by Metagenomic analysis on the same PM samples. Frankia and Paracoccus are relatively more abundant in 16S rRNA gene data, while Kocuria and Geodermatophilus are relatively more abundant in Meta-data. PM10 bacterial communities are similar to those of PM2.5 with some noticeable differences, i.e., at phylum level, more Firmicutes and less Actinobacteria present in PM10 samples than in PM2.5 samples, while at genus level, more Clostridium presents in PM10 samples. The findings in Beijing were compared with three 16S rRNA gene studies in other countries. Although the sampling locations and times are different from each other, compositions of bacterial community are similar for those sampled at the ground atmosphere. Airborne microbial communities near the ground surface are different from those sampled in the upper troposphere.

  18. Identification of selected microorganisms from activated sludge capable of benzothiazole and benzotriazole transformation.

    Science.gov (United States)

    Kowalska, Katarzyna; Felis, Ewa

    2015-01-01

    Benzothiazole (BT) and benzotriazole (BTA) are present in the environment - especially in urban and industrial areas, usually as anthropogenic micropollutants. BT and BTA have been found in the municipal and industrial wastewater, rivers, soil, groundwater, sediments and sludge. The origins of those substances' presence in the environment are various industry branches (food, chemical, metallurgical, electrical), households and surface runoff from industrial areas. Increasingly strict regulations on water quality and the fact that the discussed compounds are poorly biodegradable, make them a serious problem in the environment. Considering this, it is important to look for environmentally friendly and socially acceptable ways to remove BT and BTA. The aim of this study was to identify microorganisms capable of BT and BTA transformation or/and degradation in aquatic environment. Selected microorganisms were isolated from activated sludge. The identification of microorganisms capable of BT and BTA removal was possible using molecular biology techniques (PCR, DNA sequencing). Among isolated microorganisms of activated sludge are bacteria potentially capable of BT and BTA biotransformation and/or removal. The most common bacteria capable of BT and BTA transformation were Rhodococcus sp., Enterobacter sp., Arthrobacter sp. They can grow in a medium with BT and BTA as the only carbon source. Microorganisms previously adapted to the presence of the studied substances at a concentration of 10 mg/l, showed a greater rate of growth of colonies on media than microorganisms unconditioned to the presence of such compounds. Results of the biodegradation test suggest that BT was degraded to a greater extent than BTA, 98-100% and 11-19%, respectively.

  19. Response of soil microbial communities to roxarsone pollution along a concentration gradient.

    Science.gov (United States)

    Liu, Yaci; Zhang, Zhaoji; Li, Yasong; Wen, Yi; Fei, Yuhong

    2017-07-29

    The extensive use of roxarsone (3-nitro-4-hydroxyphenylarsonic acid) as a feed additive in the broiler poultry industry can lead to environmental arsenic contamination. This study was conducted to reveal the response of soil microbial communities to roxarsone pollution along a concentration gradient. To explore the degradation process and degradation kinetics of roxarsone concentration gradients in soil, the concentration shift of roxarsone at initial concentrations of 0, 50, 100, and 200 mg/kg, as well as that of the arsenic derivatives, was detected. The soil microbial community composition and structure accompanying roxarsone degradation were investigated by high-throughput sequencing. The results showed that roxarsone degradation was inhibited by a biological inhibitor, confirming that soil microbes were absolutely essential to its degradation. Moreover, soil microbes had considerable potential to degrade roxarsone, as a high initial concentration of roxarsone resulted in a substantially increased degradation rate. The concentrations of the degradation products HAPA (3-amino-4-hydroxyphenylarsonic acid), AS(III), and AS(V) in soils were significantly positively correlated. The soil microbial community composition and structure changed significantly across the roxarsone contamination gradient, and the addition of roxarsone decreased the microbial diversity. Some bacteria tended to be inhibited by roxarsone, while Bacillus, Paenibacillus, Arthrobacter, Lysobacter, and Alkaliphilus played important roles in roxarsone degradation. Moreover, HAPA, AS(III), and AS(V) were significantly positively correlated with Symbiobacterium, which dominated soils containing roxarsone, and their abundance increased with increasing initial roxarsone concentration. Accordingly, Symbiobacterium could serve as indicator of arsenic derivatives released by roxarsone as well as the initial roxarsone concentration. This is the first investigation of microbes closely related to roxarsone

  20. Leaf microbiota in an agroecosystem: spatiotemporal variation in bacterial community composition on field-grown lettuce.

    Science.gov (United States)

    Rastogi, Gurdeep; Sbodio, Adrian; Tech, Jan J; Suslow, Trevor V; Coaker, Gitta L; Leveau, Johan H J

    2012-10-01

    The presence, size and importance of bacterial communities on plant leaf surfaces are widely appreciated. However, information is scarce regarding their composition and how it changes along geographical and seasonal scales. We collected 106 samples of field-grown Romaine lettuce from commercial production regions in California and Arizona during the 2009-2010 crop cycle. Total bacterial populations averaged between 10(5) and 10(6) per gram of tissue, whereas counts of culturable bacteria were on average one (summer season) or two (winter season) orders of magnitude lower. Pyrosequencing of 16S rRNA gene amplicons from 88 samples revealed that Proteobacteria, Firmicutes, Bacteroidetes and Actinobacteria were the most abundantly represented phyla. At the genus level, Pseudomonas, Bacillus, Massilia, Arthrobacter and Pantoea were the most consistently found across samples, suggesting that they form the bacterial 'core' phyllosphere microbiota on lettuce. The foliar presence of Xanthomonas campestris pv. vitians, which is the causal agent of bacterial leaf spot of lettuce, correlated positively with the relative representation of bacteria from the genus Alkanindiges, but negatively with Bacillus, Erwinia and Pantoea. Summer samples showed an overrepresentation of Enterobacteriaceae sequences and culturable coliforms compared with winter samples. The distance between fields or the timing of a dust storm, but not Romaine cultivar, explained differences in bacterial community composition between several of the fields sampled. As one of the largest surveys of leaf surface microbiology, this study offers new insights into the extent and underlying causes of variability in bacterial community composition on plant leaves as a function of time, space and environment.

  1. Bacterial diversity determination using culture-dependent and culture-independent methods

    Directory of Open Access Journals (Sweden)

    M. Ghiasian

    2017-04-01

    Full Text Available Mud volcanoes are taken into consideration by geologists and oil industry experts have given their association with oil and gas reserves and methane greenhouse gas production in hydrosphere and atmosphere. Gomishan mud volcano phenomenon in the southeastern edge of the Caspian Sea, given its oil and gas resources, has been studied by some geologists in terms of geology and tectonics but not in terms of microbiology. Accordingly, it seems necessary to study this phenomenon from the perspective of microbiology in order to identify prokaryotes living in this area. Prokaryotes diversity in Mud volcano has been studied by cultivation techniques, fluorescence in situ hybridization, and denaturing gradient gel electrophoresis of PCR-amplified fragments of 16S rRNA genes. Total cell abundance in the mud volcano from 1×101-6×101per milliliter was determined by 4', 6-diamidino-2-phenylindole direct count. The detectable proportion of Archaea to Bacteria in the community by FISH was one to five. High viable counts (1 – 3 × 106 were obtained in culture media. A total of 122 isolates were obtained, 46 colonies were selected based on primarily morphological and physiological traits, and their 16S rRNA sequences were determined. The isolated genera included Halomonas (20%, Arthrobacter (5%, Kocuria (5%, Thalassobacillus (5%, Marinobacter (20%, Paracoccus (5%, Roseovarius (5%, Jeotgalicoccus (5%, Bacillus (15%, and Staphylococcus (15%. Regarding DGGE analysis, selected bands were obtained from the gels, reamplified and sequenced. Overall, 75% of the bacterial sequences were related to Rahnella and 25% related to Serratia.

  2. Microbial Community Profile and Water Quality in a Protected Area of the Caatinga Biome.

    Science.gov (United States)

    Lopes, Fabyano Alvares Cardoso; Catão, Elisa Caldeira Pires; Santana, Renata Henrique; Cabral, Anderson de Souza; Paranhos, Rodolfo; Rangel, Thiago Pessanha; de Rezende, Carlos Eduardo; Edwards, Robert A; Thompson, Cristiane C; Thompson, Fabiano L; Kruger, Ricardo Henrique

    2016-01-01

    The Caatinga is a semi-arid biome in northeast Brazil. The Paraguaçú River is located in the Caatinga biome, and part of its course is protected by the National Park of Chapada Diamantina (PNCD). In this study we evaluated the effect of PNCD protection on the water quality and microbial community diversity of this river by analyzing water samples obtained from points located inside and outside the PNCD in both wet and dry seasons. Results of water quality analysis showed higher levels of silicate, ammonia, particulate organic carbon, and nitrite in samples from the unprotected area compared with those from protected areas. Pyrosequencing of the 16S rRNA genes revealed that Burkholderiales was abundant in samples from all three sites during both seasons and was represented primarily by the genus Polynucleobacter and members of the Comamonadaceae family (e.g., genus Limnohabitans). During the dry season, the unprotected area showed a higher abundance of Flavobacterium sp. and Arthrobacter sp., which are frequently associated with the presence and/or degradation of arsenic and pesticide compounds. In addition, genes that appear to be related to agricultural impacts on the environment, as well as those involved in arsenic and cadmium resistance, copper homeostasis, and propanediol utilization, were detected in the unprotected areas by metagenomic sequencing. Although PNCD protection improves water quality, agricultural activities around the park may affect water quality within the park and may account for the presence of bacteria capable of pesticide degradation and assimilation, evidencing possible anthropogenic impacts on the Caatinga.

  3. Dysbiosis of the Fecal Microbiota in Cattle Infected with Mycobacterium avium subsp. paratuberculosis.

    Science.gov (United States)

    Fecteau, Marie-Eve; Pitta, Dipti W; Vecchiarelli, Bonnie; Indugu, Nagaraju; Kumar, Sanjay; Gallagher, Susan C; Fyock, Terry L; Sweeney, Raymond W

    2016-01-01

    Johne's disease (JD) is a chronic, intestinal infection of cattle, caused by Mycobacterium avium subsp. paratuberculosis (MAP). It results in granulomatous inflammation of the intestinal lining, leading to malabsorption, diarrhea, and weight loss. Crohn's disease (CD), a chronic, inflammatory gastrointestinal disease of humans, has many clinical and pathologic similarities to JD. Dysbiosis of the enteric microbiota has been demonstrated in CD patients. It is speculated that this dysbiosis may contribute to the intestinal inflammation observed in those patients. The purpose of this study was to investigate the diversity patterns of fecal bacterial populations in cattle infected with MAP, compared to those of uninfected control cattle, using phylogenomic analysis. Fecal samples were selected to include samples from 20 MAP-positive cows; 25 MAP-negative herdmates; and 25 MAP-negative cows from a MAP-free herd. The genomic DNA was extracted; PCR amplified sequenced on a 454 Roche platform, and analyzed using QIIME. Approximately 199,077 reads were analyzed from 70 bacterial communities (average of 2,843 reads/sample). The composition of bacterial communities differed between the 3 treatment groups (P Permanova test). Taxonomic assignment of the operational taxonomic units (OTUs) identified 17 bacterial phyla across all samples. Bacteroidetes and Firmicutes constituted more than 95% of the bacterial population in the negative and exposed groups. In the positive group, lineages of Actinobacteria and Proteobacteria increased and those of Bacteroidetes and Firmicutes decreased (P < 0.001). Actinobacteria was highly abundant (30% of the total bacteria) in the positive group compared to exposed and negative groups (0.1-0.2%). Notably, the genus Arthrobacter was found to predominate Actinobacteria in the positive group. This study indicates that MAP-infected cattle have a different composition of their fecal microbiota than MAP-negative cattle.

  4. Dysbiosis of the Fecal Microbiota in Cattle Infected with Mycobacterium avium subsp. paratuberculosis.

    Directory of Open Access Journals (Sweden)

    Marie-Eve Fecteau

    Full Text Available Johne's disease (JD is a chronic, intestinal infection of cattle, caused by Mycobacterium avium subsp. paratuberculosis (MAP. It results in granulomatous inflammation of the intestinal lining, leading to malabsorption, diarrhea, and weight loss. Crohn's disease (CD, a chronic, inflammatory gastrointestinal disease of humans, has many clinical and pathologic similarities to JD. Dysbiosis of the enteric microbiota has been demonstrated in CD patients. It is speculated that this dysbiosis may contribute to the intestinal inflammation observed in those patients. The purpose of this study was to investigate the diversity patterns of fecal bacterial populations in cattle infected with MAP, compared to those of uninfected control cattle, using phylogenomic analysis. Fecal samples were selected to include samples from 20 MAP-positive cows; 25 MAP-negative herdmates; and 25 MAP-negative cows from a MAP-free herd. The genomic DNA was extracted; PCR amplified sequenced on a 454 Roche platform, and analyzed using QIIME. Approximately 199,077 reads were analyzed from 70 bacterial communities (average of 2,843 reads/sample. The composition of bacterial communities differed between the 3 treatment groups (P < 0.001; Permanova test. Taxonomic assignment of the operational taxonomic units (OTUs identified 17 bacterial phyla across all samples. Bacteroidetes and Firmicutes constituted more than 95% of the bacterial population in the negative and exposed groups. In the positive group, lineages of Actinobacteria and Proteobacteria increased and those of Bacteroidetes and Firmicutes decreased (P < 0.001. Actinobacteria was highly abundant (30% of the total bacteria in the positive group compared to exposed and negative groups (0.1-0.2%. Notably, the genus Arthrobacter was found to predominate Actinobacteria in the positive group. This study indicates that MAP-infected cattle have a different composition of their fecal microbiota than MAP-negative cattle.

  5. Monitoring bioremediation of atrazine in soil microcosms using molecular tools

    International Nuclear Information System (INIS)

    Sagarkar, Sneha; Mukherjee, Shinjini; Nousiainen, Aura; Björklöf, Katarina; Purohit, Hemant J.; Jørgensen, Kirsten S.; Kapley, Atya

    2013-01-01

    Molecular tools in microbial community analysis give access to information on catabolic potential and diversity of microbes. Applied in bioremediation, they could provide a new dimension to improve pollution control. This concept has been demonstrated in the study using atrazine as model pollutant. Bioremediation of the herbicide, atrazine, was analyzed in microcosm studies by bioaugmentation, biostimulation and natural attenuation. Genes from the atrazine degrading pathway atzA/B/C/D/E/F, trzN, and trzD were monitored during the course of treatment and results demonstrated variation in atzC, trzD and trzN genes with time. Change in copy number of trzN gene under different treatment processes was demonstrated by real-time PCR. The amplified trzN gene was cloned and sequence data showed homology to genes reported in Arthrobacter and Nocardioides. Results demonstrate that specific target genes can be monitored, quantified and correlated to degradation analysis which would help in predicting the outcome of any bioremediation strategy. - Highlights: ► Degradation of herbicide, atrazine. ► Comparison of bioremediation via bioaugmentation, biostimulation and natural attenuation. ► Gene profile analysis in all treatments. ► Variation in trzN gene numbers correlated to degradation efficiency. ► Cloning and sequence analysis of trzN gene demonstrates very high homology to reported gene. - This study demonstrates the use of molecular tools in bioremediation to monitor and track target genes; correlates the results with degradation and thereby predicts the efficiency of treatment.

  6. Characterization of the Cultivable Gut Microflora in Wild-Caught 
Mediterranean Fish Species.

    Science.gov (United States)

    Jammal, Ahmad; Bariche, Michel; Zu Dohna, Heinrich; Kambris, Zakaria

    2017-05-01

    Microflora of the gastrointestinal tract plays important roles in food digestion, nutrient absorption and in host defense against ingested pathogens. Several studies have focused on the microflora of farmed fishes, but the gut flora of wild fishes remains poorly characterized. The aim of this work was to provide an overview of the bacteria colonizing the gut of wild-caught fishes and to determine whether some bacterial species can be pathogenic. We isolated cultivable bacteria from fifteen wild-caught Mediterranean fish species corresponding to different habitat, diet and origin. Bacterial species identity was determined by 16s rRNA gene sequencing for the 61 isolates. The potential pathogenicity of isolated bacteria was investigated using fruit fly (Drosophila melanogaster) and zebrafish (Danio rerio) as model organisms. Two bacterial strains (Serratia sp. and Aeromonas salmonicida) were lethal when microinjected to Drosophila, while zebrafish did not develop any disease when exposed to any of 34 isolated bacterial strains. However, it was interesting to note that two bacterial strains (Shewanella and Arthrobacter) isolated from marine fishes were able to colonize the guts of freshwater zebrafish. The results of this study give an overview of the bacterial species found in the guts of wild fishes living off Beirut seashore. It shows that some parameters believed to be limiting factors to host-gut colonization by bacteria can be overcome by some species. This pilot study could be extended by sampling a larger number of fish species with several specimens per fish species, and by identifying uncultivable bacteria that reside in the fish guts. Our results may have implications for the utilization of certain bacterial species in fish farming or their use as bio-indicators for water and/or food quality.

  7. Radiation disinfection of rice-straw products

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Hitoshi; Ishigaki, Isao (Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment); Ohki, Yumi

    1991-11-01

    For the quarantine treatment of rice-straw products from foreign countries, irradiation effects of gamma-rays and electron beams on plant pathogenic microorganisms especially on fungi were investigated. The total aerobic bacteria in rice-straw was determined to be 3x10{sup 7} - 3x10{sup 8} per gram which consisted mainly of Pseudomonas, Flavobacterium, Arthrobacter and Erwinia. The principal bacteria in rice-straw could be eliminated with 5 kGy of gamma irradiation. Deinococcus proteolyticus and Pseudomonas radiora were the main survivors at 5 to 12 kGy of irradiation. Saprophytic fungus which belongs to Dimorphospora also survived up to 8 kGy of irradiation. The D{sub 10} values of 26 strains of fungi isolated from rice-straw were 1.1 to 2.5 times higher in the dry condition compared to the values when irradiated in 0.067 M phosphate buffer solution. The induction dose in the dry condition also increased from 1.5 to 10 times than that in the wet condition. In the case of electron beam irradiation of fungi under dry conditions, D{sub 10} values were about 1.3 times higher than that of gamma irradiation. From this study, the dose necessary to reduce the plant pathogenic fungi in rice-straw at a level below 10{sup -4} per gram was estimated to be as 7-8 kGy for gamma-irradiation and 10 kGy for electron beam irradiation. (author).

  8. Spatial distribution of microbial communities associated with dune landform in the Gurbantunggut Desert, China.

    Science.gov (United States)

    Liu, Ruyin; Li, Ke; Zhang, Hongxun; Zhu, Junge; Joshi, DevRaj

    2014-11-01

    The microbial community compositions and potential ammonia oxidation in the topsoil at different positions of sand dune (stoss slope, crest, lee slope, and interdune) from the Gurbantunggut Desert, the largest semi-fixed desert in China, were investigated using several molecular methods. Actinobacteria and Proteobacteria (especially Alphaproteobacteria) were commonly the dominant taxa across all soil samples. Bacterial communities were similar in soils collected from the stoss slopes and interdunes (HC-BSCs, biological soil crusts with a high abundance of cyanobacteria), containing more abundant cyanobacterial populations (16.9-24.5%) than those (0.2-0.7% of Cyanobacteria) in the crests and lee slopes (LC-BSCs, biological soil crusts with a low abundance of cyanobacteria). The Cyanobacteria were mainly composed of Microcoleus spp., and quantitative PCR analysis revealed that 16S rRNA gene copy numbers of Cyanobacteria (especially genus Microcoleus) were at least two orders of magnitude higher in HC-BSCs than in LC-BSCs. Heterotrophic Geodermatophilus spp. frequently occurred in HC-BSCs (2.5-8.0%), whereas genera Arthrobacter, Bacillus, and Segetibacter were significantly abundant in LC-BSC communities. By comparison, the desert archaeal communities were less complex, and were dominated by Nitrososphaera spp. The amoA gene abundance of ammonia-oxidizing archaea (AOA) was higher than that of ammonia-oxidizing bacteria (AOB) in all soil samples, particularly in the interdunal soils (10(6)-10(8) archaeal amoA gene copies per gram dry soil), indicating that AOA possibly dominate the ammonia oxidation at the interdunes.

  9. Bacterial diversity and community along the succession of biological soil crusts in the Gurbantunggut Desert, Northern China.

    Science.gov (United States)

    Zhang, Bingchang; Kong, Weidong; Wu, Nan; Zhang, Yuanming

    2016-06-01

    Biological soil crusts (BSCs) are common and play critical roles in semi-arid and arid ecosystems. Bacteria, as an important community in BSCs, play critical roles in biochemical processes. However, how bacterial diversity and community change in different successional stages of BSCs is still unknown. We used 454 pyrosequencing of 16S rRNA to investigate the bacterial composition and community, and the relationships between bacterial composition and environmental factors were also explored. In different successional stages of BSCs, the number of bacteria operational taxonomic units (OTUs) detected in each sample ranged from 2572 to 3157. Proteobacteria, Cyanobacteria, Bacteroidetes were dominant in BSCs, followed by Firmicutes, Acidobacteria, and Actinobacteria. At the successional stages of BSCs, bacterial communities, OTU composition and their relative abundance notably differentiated, and Cyanobacteria, especially Microcoleus vaginatus, dominated algal crust and lichen crust, and were the main C-fixing bacteria in BSCs. Proteobacteria and Bacteroidetes increased with the development of BSCs. OTUs related to Planomicrobium Chinese, Desulfobulbus sp., Desulfomicrobium sp., Arthrobacter sp., and Ahhaerbacter sp. showed higher relative abundance in bare sand than other successional stages of BSCs, while relative abundance of Sphingomonas sp. Niastella sp., Pedobacter, Candidatus solobacter, and Streptophyta increased with the development of BSCs. In successional stages of BSCs, bacterial OTUs composition demonstrated strong correlations with soil nutrients, soil salts, and soil enzymes. Additionally, variation of bacterial composition led to different ecological function. In bare sand, some species were related with mineral metabolism or promoting plant growth, and in algal crust and lichen crust, C-fixing bacteria increased and accumulated C to the desert soil. In later developed stage of BSCs, bacteria related with decomposition of organic matter, such as

  10. Immersion Refractometry of Isolated Bacterial Cell Walls

    Science.gov (United States)

    Marquis, Robert E.

    1973-01-01

    Immersion-refractometric and light-scattering measurements were adapted to determinations of average refractive indices and physical compactness of isolated bacterial cell walls. The structures were immersed in solutions containing various concentrations of polymer molecules that cannot penetrate into wall pores, and then an estimate was made of the polymer concentration or the refractive index of the polymer solution in which light scattering was reduced to zero. Because each wall preparation was heterogeneous, the refractive index of the medium for zero light scattering had to be estimated by extrapolation. Refractive indices for walls suspended in bovine serum albumin solutions ranged from 1.348 for walls of the rod form of Arthrobacter crystallopoietes to 1.382 for walls of the teichoic acid deficient, 52A5 strain of Staphylococcus aureus. These indices were used to calculate approximate values for solids content per milliliter, and the calculated values agreed closely with those estimated from a knowledge of dextran-impermeable volumes per gram, dry weight, of the walls. When large molecules such as dextrans or serum albumin were used for immersion refractometry, the refractive indices obtained were for entire walls, including both wall polymers and wall water. When smaller molecules that can penetrate wall pores to various extents were used with Micrococcus lysodeikticus walls, the average, apparent refractive index of the structures increased as the molecular size of probing molecules was decreased. It was possible to obtain an estimate of 1.45 to 1.46 for the refractive index of wall polymers, predominantly peptidoglycans in this case, by extrapolating the curve for refractive index versus molecular radius to a value of 0.2 nm, the approximate radius of a water molecule. This relatively low value for polymer refractive index was interpreted as evidence in favor of the amorphous, elastic model of peptidoglycan structure and against the crystalline, rigid

  11. The Effect of Bicarbonate on the Microbial Dissolution of Autunite Mineral in the Presence of Gram-Positive Bacteria

    Energy Technology Data Exchange (ETDEWEB)

    Sepulveda-Medina, Paola; Katsenovich, Yelena; Wellman, Dawn M.; Lagos, Leonel

    2015-06-01

    Bacteria are key players in the processes that govern fate and transport of contaminants. The uranium release from Na and Ca-autunite by Arthrobacter oxydans strain G968 was evaluated in the presence of bicarbonate ions. This bacterium was previously isolated from Hanford Site soil and in earlier prescreening tests demonstrated low tolerance to U(VI) toxicity compared to other A.oxydans isolates. Experiments were conducted using glass serum bottles as mixed bioreactors and sterile 6-well cell culture plates with inserts separating bacteria cells from mineral solids. Reactors containing phosphorus-limiting media were amended with bicarbonate ranging between 0-10 mM and metaautunite solids to provide a U(VI) concentration of 4.4 mmol/L. Results showed that in the presence of bicarbonate, A.oxydans G968 was able to enhance the release of U(VI) from Na and Ca autunite at the same capacity as other A.oxydans isolates with relatively high tolerance to U(VI). The effect of bacterial strains on autunite dissolution decreases as the concentration of bicarbonate increases. The results illustrate that direct interaction between the bacteria and the mineral is not necessary to result in U (VI) biorelease from autunite. The formation of secondary calcium-phosphate mineral phases on the surface of the mineral during the dissolution can ultimately reduce the natural autunite mineral contact area, which bacterial cells can access. This thereby reduces the concentration of uranium released into the solution. This study provides a better understanding of the interactions between meta-autunite and microbes in conditions mimicking arid and semiarid subsurface environments of western U.S.

  12. Testing soil-like substrate for growing plants in bioregenerative life support systems

    Science.gov (United States)

    Gros, J. B.; Lasseur, Ch.; Tikhomirov, A. A.; Manukovsky, N. S.; Kovalev, V. S.; Ushakova, S. A.; Zolotukhin, I. G.; Tirranen, L. S.; Karnachuk, R. A.; Dorofeev, V. Yu.

    We studied soil-like substrate (SLS) as a potential candidate for plant cultivation in bioregenerative life support systems (BLSS). The SLS was obtained by successive conversion of wheat straw by oyster mushrooms and worms. Mature SLS contained 9.5% humic acids and 4.9% fulvic acids. First, it was shown that wheat, bean and cucumber yields as well as radish yields when cultivated on mature SLS were comparable to yields obtained on a neutral substrate (expanded clay aggregate) under hydroponics. Second, the possibility of increasing wheat and radish yields on the SLS was assessed at three levels of light intensity: 690, 920 and 1150 μmol m -2 s -1 of photosynthetically active radiation (PAR). The highest wheat yield was obtained at 920 μmol m -2 s -1, while radish yield increased steadily with increasing light intensity. Third, long-term SLS fertility was tested in a BLSS model with mineral and organic matter recycling. Eight cycles of wheat and 13 cycles of radish cultivation were carried out on the SLS in the experimental system. Correlation coefficients between SLS nitrogen content and total wheat biomass and grain yield were 0.92 and 0.97, respectively, and correlation coefficients between nitrogen content and total radish biomass and edible root yield were 0.88 and 0.87, respectively. Changes in hormone content (auxins, gibberellins, cytokinins and abscisic acid) in the SLS during matter recycling did not reduce plant productivity. Quantitative and species compositions of the SLS and irrigation water microflora were also investigated. Microbial community analysis of the SLS showed bacteria from Bacillus, Pseudomonas, Proteus, Nocardia, Mycobacterium, Arthrobacter and Enterobacter genera, and fungi from Trichoderma, Penicillium, Fusarium, Aspergillus, Mucor, Botrytis, and Cladosporium genera.

  13. Leaf microbiota in an agroecosystem: spatiotemporal variation in bacterial community composition on field-grown lettuce

    Science.gov (United States)

    Rastogi, Gurdeep; Sbodio, Adrian; Tech, Jan J; Suslow, Trevor V; Coaker, Gitta L; Leveau, Johan H J

    2012-01-01

    The presence, size and importance of bacterial communities on plant leaf surfaces are widely appreciated. However, information is scarce regarding their composition and how it changes along geographical and seasonal scales. We collected 106 samples of field-grown Romaine lettuce from commercial production regions in California and Arizona during the 2009–2010 crop cycle. Total bacterial populations averaged between 105 and 106 per gram of tissue, whereas counts of culturable bacteria were on average one (summer season) or two (winter season) orders of magnitude lower. Pyrosequencing of 16S rRNA gene amplicons from 88 samples revealed that Proteobacteria, Firmicutes, Bacteroidetes and Actinobacteria were the most abundantly represented phyla. At the genus level, Pseudomonas, Bacillus, Massilia, Arthrobacter and Pantoea were the most consistently found across samples, suggesting that they form the bacterial ‘core' phyllosphere microbiota on lettuce. The foliar presence of Xanthomonas campestris pv. vitians, which is the causal agent of bacterial leaf spot of lettuce, correlated positively with the relative representation of bacteria from the genus Alkanindiges, but negatively with Bacillus, Erwinia and Pantoea. Summer samples showed an overrepresentation of Enterobacteriaceae sequences and culturable coliforms compared with winter samples. The distance between fields or the timing of a dust storm, but not Romaine cultivar, explained differences in bacterial community composition between several of the fields sampled. As one of the largest surveys of leaf surface microbiology, this study offers new insights into the extent and underlying causes of variability in bacterial community composition on plant leaves as a function of time, space and environment. PMID:22534606

  14. Diverse microbial species survive high ammonia concentrations

    Science.gov (United States)

    Kelly, Laura C.; Cockell, Charles S.; Summers, Stephen

    2012-04-01

    Planetary protection regulations are in place to control the contamination of planets and moons with terrestrial micro-organisms in order to avoid jeopardizing future scientific investigations relating to the search for life. One environmental chemical factor of relevance in extraterrestrial environments, specifically in the moons of the outer solar system, is ammonia (NH3). Ammonia is known to be highly toxic to micro-organisms and may disrupt proton motive force, interfere with cellular redox reactions or cause an increase of cell pH. To test the survival potential of terrestrial micro-organisms exposed to such cold, ammonia-rich environments, and to judge whether current planetary protection regulations are sufficient, soil samples were exposed to concentrations of NH3 from 5 to 35% (v/v) at -80°C and room temperature for periods up to 11 months. Following exposure to 35% NH3, diverse spore-forming taxa survived, including representatives of the Firmicutes (Bacillus, Sporosarcina, Viridibacillus, Paenibacillus, Staphylococcus and Brevibacillus) and Actinobacteria (Streptomyces). Non-spore forming organisms also survived, including Proteobacteria (Pseudomonas) and Actinobacteria (Arthrobacter) that are known to have environmentally resistant resting states. Clostridium spp. were isolated from the exposed soil under anaerobic culture. High NH3 was shown to cause a reduction in viability of spores over time, but spore morphology was not visibly altered. In addition to its implications for planetary protection, these data show that a large number of bacteria, potentially including spore-forming pathogens, but also environmentally resistant non-spore-formers, can survive high ammonia concentrations.

  15. Microbes at Surface-Air Interfaces: The Metabolic Harnessing of Relative Humidity, Surface Hygroscopicity, and Oligotrophy for Resilience

    Science.gov (United States)

    Stone, Wendy; Kroukamp, Otini; Korber, Darren R.; McKelvie, Jennifer; Wolfaardt, Gideon M.

    2016-01-01

    The human environment is predominantly not aqueous, and microbes are ubiquitous at the surface-air interfaces with which we interact. Yet microbial studies at surface-air interfaces are largely survival-oriented, whilst microbial metabolism has overwhelmingly been investigated from the perspective of liquid saturation. This study explored microbial survival and metabolism under desiccation, particularly the influence of relative humidity (RH), surface hygroscopicity, and nutrient availability on the interchange between these two phenomena. The combination of a hygroscopic matrix (i.e., clay or 4,000 MW polyethylene glycol) and high RH resulted in persistent measurable microbial metabolism during desiccation. In contrast, no microbial metabolism was detected at (a) hygroscopic interfaces at low RH, and (b) less hygroscopic interfaces (i.e., sand and plastic/glass) at high or low RH. Cell survival was conversely inhibited at high RH and promoted at low RH, irrespective of surface hygroscopicity. Based on this demonstration of metabolic persistence and survival inhibition at high RH, it was proposed that biofilm metabolic rates might inversely influence whole-biofilm resilience, with ‘resilience’ defined in this study as a biofilm’s capacity to recover from desiccation. The concept of whole-biofilm resilience being promoted by oligotrophy was supported in desiccation-tolerant Arthrobacter spp. biofilms, but not in desiccation-sensitive Pseudomonas aeruginosa biofilms. The ability of microbes to interact with surfaces to harness water vapor during desiccation was demonstrated, and potentially to harness oligotrophy (the most ubiquitous natural condition facing microbes) for adaptation to desiccation. PMID:27746774

  16. The ability of microbial community of Lake Baikal bottom sediments associated with gas discharge to carry out the transformation of organic matter under thermobaric conditions

    Directory of Open Access Journals (Sweden)

    Sergei Viktorovich Bukin

    2016-05-01

    Full Text Available The ability to compare the composition and metabolic potential of microbial communities inhabiting the subsurface sediment in geographically distinct locations is one of the keys to understanding the evolution and function of the subsurface biosphere. Prospective areas for study of the subsurface biosphere are the sites of hydrocarbon discharges on the bottom of the Lake Baikal rift, where ascending fluxes of gas-saturated fluids and oil from deep layers of bottom sediments seep into near-surface sediment. The samples of surface sediments collected in the area of the Posolskaya Bank methane seep were cultured for 17 months under thermobaric conditions (80°С, 5 MPa with the addition of complementary organic substrate, and a different composition for the gas phase. After incubation, the presence of intact cells of microorganisms, organic matter transformation and the formation of oil biomarkers was confirmed in the samples, with the addition of Baikalian diatom alga Synedra acus detritus, and gas mixture СH4:H2:CO2. Taxonomic assignment of the 16S rRNA sequence data indicates that the predominant sequences in the enrichment were Sphingomonas (55.3%, Solirubrobacter (27.5% and Arthrobacter (16.6%. At the same time, in heat-killed sediment and in sediment without any additional substrates, which were cultivated in a CH4 atmosphere, no geochemical changes were detected, nor the presence of intact cells and 16S rRNA sequences of Bacteria and Archaea. This data may suggest that the decomposition of organic matter under culturing conditions could be performed by microorganisms from low-temperature sediment layers. One possible explanation of this phenomenon is migration of the representatives of the deep thermophilic community through fault zones in the near surface sediment layers, together with gas-bearing fluids.

  17. CARACTERIZACIÓN FENOTIPICA Y MOLECULAR DE POBLACIONES BACTERIANAS AISLADAS DE UN SUELO CONTAMINADO CON DIESEL Y SOMETIDO A DOS TECNOLOGÍAS DE BIORREMEDIACIÓN

    Directory of Open Access Journals (Sweden)

    ARRIETA R. OLGA M.

    2012-12-01

    Full Text Available En este estudio se presenta la biorremediación como alternativa para la recuperación de ecosistemas contaminados. En este trabajo se realizó un derrame experimental de diesel sobre un suelo de pastoreo, el cual fue remediado haciendo uso de dos tecnologías de biorremediación: atenuación natural; conocida como la capacidad natural de los microorganismos nativos para degradar en un tiempo determinado cualquier compuesto xenobiótico, y bioestimulación; conocida como la adición al medio de nutrientes (fosforo y nitrógeno con el fin de estimular el metabolismo de los microorganismos nativos, logrando con esto acelerar el proceso de degradación. Los resultados de la prueba de respirometría indicaron que ambos tratamientos produjeron valores significativos de remoción del hidrocarburo pero el tratamiento de bioestimulación se destacó con el 98,17% de degradación. Se obtuvieron siete aislamientos bacterianos a partir de las siembras realizadas, según la caracterización molecular pertenecen a los géneros: Enterobacter, Bacillus, Arthrobacter, Sanguibacter, Staphylococcus y Flavobacterium. Todos los aislamientos fueron capaces de metabolizar el diesel como fuente de carbono y energía; por ello y teniendo en cuenta que para algunos de estos microorganismos su papel en biorremediación no ha sido estudiado extensivamente, se recomienda continuar con su evaluación para conocer cuál es realmente su potencial para la solución de problemas ambientales.

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

    Directory of Open Access Journals (Sweden)

    Luis Oviedo Z

    2017-05-01

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

  19. Bacterially Induced Weathering of Ultramafic Rock and Its Implications for Phytoextraction

    Science.gov (United States)

    Kidd, Petra; Kuffner, Melanie; Prieto-Fernández, Ángeles; Hann, Stephan; Monterroso, Carmela; Sessitsch, Angela; Wenzel, Walter; Puschenreiter, Markus

    2013-01-01

    The bioavailability of metals in soil is often cited as a limiting factor of phytoextraction (or phytomining). Bacterial metabolites, such as organic acids, siderophores, or biosurfactants, have been shown to mobilize metals, and their use to improve metal extraction has been proposed. In this study, the weathering capacities of, and Ni mobilization by, bacterial strains were evaluated. Minimal medium containing ground ultramafic rock was inoculated with either of two Arthrobacter strains: LA44 (indole acetic acid [IAA] producer) or SBA82 (siderophore producer, PO4 solubilizer, and IAA producer). Trace elements and organic compounds were determined in aliquots taken at different time intervals after inoculation. Trace metal fractionation was carried out on the remaining rock at the end of the experiment. The results suggest that the strains act upon different mineral phases. LA44 is a more efficient Ni mobilizer, apparently solubilizing Ni associated with Mn oxides, and this appeared to be related to oxalate production. SBA82 also leads to release of Ni and Mn, albeit to a much lower extent. In this case, the concurrent mobilization of Fe and Si indicates preferential weathering of Fe oxides and serpentine minerals, possibly related to the siderophore production capacity of the strain. The same bacterial strains were tested in a soil-plant system: the Ni hyperaccumulator Alyssum serpyllifolium subsp. malacitanum was grown in ultramafic soil in a rhizobox system and inoculated with each bacterial strain. At harvest, biomass production and shoot Ni concentrations were higher in plants from inoculated pots than from noninoculated pots. Ni yield was significantly enhanced in plants inoculated with LA44. These results suggest that Ni-mobilizing inoculants could be useful for improving Ni uptake by hyperaccumulator plants. PMID:23793627

  20. Psychromicrobium silvestre gen. nov., sp. nov., an actinobacterium isolated from alpine forest soils.

    Science.gov (United States)

    Schumann, Peter; Zhang, De-Chao; França, Luís; Albuquerque, Luciana; da Costa, Milton S; Margesin, Rosa

    2017-03-01

    Two Gram-stain-variable, non-motile, catalase-positive and cytochrome c oxidase-negative bacteria, designated AK20-18 T and AM20-54, were isolated from forest soil samples collected in the Italian Alps. Growth occurred at a temperature range of 5-30 °C, at pH 6-9 and in the presence of 0-5 % (w/v) NaCl. The 16S rRNA gene sequence similarity between strains AK20-18 T and AM20-54 was 100 %. Phylogenetic analysis based on 16S rRNA gene sequence showed that strain AK20-18 T had highest 16S rRNA gene sequence similarity with the type strain of Arthrobacter psychrochitiniphilus (96.9 %). The cell-wall peptidoglycan structure of strain AK20-18 T was of the type A3alpha l-Lys-l-Thr-l-Ala2 (A11.27). The whole-cell sugars were galactose, ribose and lesser amounts of mannose. The major respiratory quinone of the two strains was menaquinone 9(H2) [MK-9(H2)], whereas MK-10(H2) was a minor component. The polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and unknown glycolipids. The major cellular fatty acids were anteiso-C15 : 0, iso-C15 : 0, iso-C16 : 0 and anteiso-C17 : 0. The genomic DNA G+C content was 59.9 mol%. Combined data of phylogenetic, phenotypic and chemotaxonomic analyses demonstrated that strains AK20-18 T and AM20-54 represent a novel genus and species, for which the name Psychromicrobium silvestre gen. nov., sp. nov. is proposed. The type strain of Psychromicrobium silvestregen. nov., sp. nov. is AK20-18 T (=DSM 102047 T =LMG 29369 T ).

  1. Chemical and microbiological characterization of an aged PCB-contaminated soil.

    Science.gov (United States)

    Stella, T; Covino, S; Burianová, E; Filipová, A; Křesinová, Z; Voříšková, J; Větrovský, T; Baldrian, P; Cajthaml, T

    2015-11-15

    This study was aimed at complex characterization of three soil samples (bulk soil, topsoil and rhizosphere soil) from a site historically contaminated with polychlorinated biphenyls (PCB). The bulk soil was the most highly contaminated, with a PCB concentration of 705.95 mg kg(-1), while the rhizosphere soil was the least contaminated (169.36 mg kg(-1)). PCB degradation intermediates, namely chlorobenzoic acids (CBAs), were detected in all the soil samples, suggesting the occurrence of microbial transformation processes over time. The higher content of organic carbon in the topsoil and rhizosphere soil than in the bulk soil could be linked to the reduced bioaccessibility (bioavailability) of these chlorinated pollutants. However, different proportions of the PCB congener contents and different bioaccessibility of the PCB homologues indicate microbial biotransformation of the compounds. The higher content of organic carbon probably also promoted the growth of microorganisms, as revealed by phospholipid fatty acid (PFLA) quantification. Tag-encoded pyrosequencing analysis showed that the bacterial community structure was significantly similar among the three soils and was predominated by Proteobacteria (44-48%) in all cases. Moreover, analysis at lower taxonomic levels pointed to the presence of genera (Sphingomonas, Bulkholderia, Arthrobacter, Bacillus) including members with reported PCB removal abilities. The fungal community was mostly represented by Basidiomycota and Ascomycota, which accounted for >80% of all the sequences detected in the three soils. Fungal taxa with biodegradation potential (Paxillus, Cryptococcus, Phoma, Mortierella) were also found. These results highlight the potential of the indigenous consortia present at the site as a starting point for PCB bioremediation processes. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Bacterial community structure and diversity responses to the direct revegetation of an artisanal zinc smelting slag after 5 years.

    Science.gov (United States)

    Luo, Youfa; Wu, Yonggui; Wang, Hu; Xing, Rongrong; Zheng, Zhilin; Qiu, Jing; Yang, Lian

    2018-05-01

    This comparative field study examined the responses of bacterial community structure and diversity to the revegetation of zinc (Zn) smelting waste slag with eight plant species after 5 years. The microbial community structure of waste slag with and without vegetation was evaluated using high-throughput sequencing. The physiochemical properties of Zn smelting slag after revegetation with eight plant rhizospheres for 5 years were improved compared to those of bulk slag. Revegetation significantly increased the microbial community diversity in plant rhizospheres, and at the phylum level, Proteobacteria, Acidobacteria, and Bacteroidetes were notably more abundant in rhizosphere slags than those in bulk waste slag. Additionally, revegetation increased the relative abundance of plant growth-promoting rhizobacteria such as Flavobacterium, Streptomyces, and Arthrobacter as well as symbiotic N 2 fixers such as Bradyrhizobium. Three dominant native plant species (Arundo donax, Broussonetia papyrifera, and Robinia pseudoacacia) greatly increased the quality of the rhizosphere slags. Canonical correspondence analysis showed that the differences in bacterial community structure between the bulk and rhizosphere slags were explained by slag properties, i.e., pH, available copper (Cu) and lead (Pb), moisture, available nitrogen (N), phosphorus (P), and potassium (K), and organic matter (OM); however, available Zn and cadmium (Cd) contents were the slag parameters that best explained the differences between the rhizosphere communities of the eight plant species. The results suggested that revegetation plays an important role in enhancing bacterial community abundance and diversity in rhizosphere slags and that revegetation may also regulate microbiological properties and diversity mainly through changes in heavy metal bioavailability and physiochemical slag characteristics.

  3. Metabolomic and high-throughput sequencing analysis—modern approach for the assessment of biodeterioration of materials from historic buildings

    Science.gov (United States)

    Gutarowska, Beata; Celikkol-Aydin, Sukriye; Bonifay, Vincent; Otlewska, Anna; Aydin, Egemen; Oldham, Athenia L.; Brauer, Jonathan I.; Duncan, Kathleen E.; Adamiak, Justyna; Sunner, Jan A.; Beech, Iwona B.

    2015-01-01

    Preservation of cultural heritage is of paramount importance worldwide. Microbial colonization of construction materials, such as wood, brick, mortar, and stone in historic buildings can lead to severe deterioration. The aim of the present study was to give modern insight into the phylogenetic diversity and activated metabolic pathways of microbial communities colonized historic objects located in the former Auschwitz II–Birkenau concentration and extermination camp in Oświecim, Poland. For this purpose we combined molecular, microscopic and chemical methods. Selected specimens were examined using Field Emission Scanning Electron Microscopy (FESEM), metabolomic analysis and high-throughput Illumina sequencing. FESEM imaging revealed the presence of complex microbial communities comprising diatoms, fungi and bacteria, mainly cyanobacteria and actinobacteria, on sample surfaces. Microbial diversity of brick specimens appeared higher than that of the wood and was dominated by algae and cyanobacteria, while wood was mainly colonized by fungi. DNA sequences documented the presence of 15 bacterial phyla representing 99 genera including Halomonas, Halorhodospira, Salinisphaera, Salinibacterium, Rubrobacter, Streptomyces, Arthrobacter and nine fungal classes represented by 113 genera including Cladosporium, Acremonium, Alternaria, Engyodontium, Penicillium, Rhizopus, and Aureobasidium. Most of the identified sequences were characteristic of organisms implicated in deterioration of wood and brick. Metabolomic data indicated the activation of numerous metabolic pathways, including those regulating the production of primary and secondary metabolites, for example, metabolites associated with the production of antibiotics, organic acids and deterioration of organic compounds. The study demonstrated that a combination of electron microscopy imaging with metabolomic and genomic techniques allows to link the phylogenetic information and metabolic profiles of microbial

  4. Metabolomic and high-throughput sequencing analysis – modern approach for the assessment of biodeterioration of materials from historic buildings

    Directory of Open Access Journals (Sweden)

    Beata eGutarowska

    2015-09-01

    Full Text Available Preservation of cultural heritage is of paramount importance worldwide. Microbial colonization of construction materials, such as wood, brick, mortar and stone in historic buildings can lead to severe deterioration. The aim of the present study was to give modern insight into the phylogenetic diversity and activated metabolic pathways of microbial communities colonized historic objects located in the former Auschwitz II-Birkenau concentration and extermination camp in Oświęcim, Poland. For this purpose we combined molecular, microscopic and chemical methods. Selected specimens were examined using Field Emission Scanning Electron Microscopy (FESEM, metabolomic analysis and high-throughput Illumina sequencing. FESEM imaging revealed the presence of complex microbial communities comprising diatoms, fungi and bacteria, mainly cyanobacteria and actinobacteria, on sample surfaces. Microbial diversity of brick specimens appeared higher than that of the wood and was dominated by algae and cyanobacteria, while wood was mainly colonized by fungi. DNA sequences documented the presence of 15 bacterial phyla representing 99 genera including Halomonas, Halorhodospira, Salinisphaera, Salinibacterium, Rubrobacter, Streptomyces, Arthrobacter and 9 fungal classes represented by 113 genera including Cladosporium, Acremonium, Alternaria, Engyodontium, Penicillium, Rhizopus and Aureobasidium. Most of the identified sequences were characteristic of organisms implicated in deterioration of wood and brick. Metabolomic data indicated the activation of numerous metabolic pathways, including those regulating the production of primary and secondary metabolites, for example, metabolites associated with the production of antibiotics, organic acids and deterioration of organic compounds. The study demonstrated that a combination of electron microscopy imaging with metabolomic and genomic techniques allows to link the phylogenetic information and metabolic profiles of

  5. Metabolomic and high-throughput sequencing analysis-modern approach for the assessment of biodeterioration of materials from historic buildings.

    Science.gov (United States)

    Gutarowska, Beata; Celikkol-Aydin, Sukriye; Bonifay, Vincent; Otlewska, Anna; Aydin, Egemen; Oldham, Athenia L; Brauer, Jonathan I; Duncan, Kathleen E; Adamiak, Justyna; Sunner, Jan A; Beech, Iwona B

    2015-01-01

    Preservation of cultural heritage is of paramount importance worldwide. Microbial colonization of construction materials, such as wood, brick, mortar, and stone in historic buildings can lead to severe deterioration. The aim of the present study was to give modern insight into the phylogenetic diversity and activated metabolic pathways of microbial communities colonized historic objects located in the former Auschwitz II-Birkenau concentration and extermination camp in Oświecim, Poland. For this purpose we combined molecular, microscopic and chemical methods. Selected specimens were examined using Field Emission Scanning Electron Microscopy (FESEM), metabolomic analysis and high-throughput Illumina sequencing. FESEM imaging revealed the presence of complex microbial communities comprising diatoms, fungi and bacteria, mainly cyanobacteria and actinobacteria, on sample surfaces. Microbial diversity of brick specimens appeared higher than that of the wood and was dominated by algae and cyanobacteria, while wood was mainly colonized by fungi. DNA sequences documented the presence of 15 bacterial phyla representing 99 genera including Halomonas, Halorhodospira, Salinisphaera, Salinibacterium, Rubrobacter, Streptomyces, Arthrobacter and nine fungal classes represented by 113 genera including Cladosporium, Acremonium, Alternaria, Engyodontium, Penicillium, Rhizopus, and Aureobasidium. Most of the identified sequences were characteristic of organisms implicated in deterioration of wood and brick. Metabolomic data indicated the activation of numerous metabolic pathways, including those regulating the production of primary and secondary metabolites, for example, metabolites associated with the production of antibiotics, organic acids and deterioration of organic compounds. The study demonstrated that a combination of electron microscopy imaging with metabolomic and genomic techniques allows to link the phylogenetic information and metabolic profiles of microbial communities

  6. Investigation of bacterial transport in the large-block test, a thermally perturbed block of Topopah Spring Tuff

    International Nuclear Information System (INIS)

    Chen, C. I.; Chuu, Y. J.; Lin, W.; Meike, A.; Sawvel, A.

    1998-01-01

    This study investigates the transport of bacteria in a large, thermally perturbed block of Topopah Spring tuff. The study was part of the Large-Block Test (LBT), thermochemical and physical studies conducted on a 10 ft x 10 ft x 14 ft block of volcanic tuff excavated on 5 of 6 sides out of Fran Ridge, Nevada. Two bacterial species, Bacillus subtilis and Arthrobacter oxydans, were isolated from the Yucca Mountain tuff. Natural mutants that can grow under the simultaneous presence of the two antibiotics, streptomycin and rifampicin, were selected from these species by laboratory procedures. The double-drug-resistant mutants, which could be thus distinguished from the indigenous species, were injected into the five heater boreholes of the large block hours before heating was initiated. The temperature, as measured 5 cm above one of the heater boreholes, rose slowly and steadily over a matter of months to a maximum of 142 C. Samples (cotton cloths inserted the length of the hole, glass fiber swabs, and filter papers) were collected from the boreholes that were approximately 5 ft below the injection points. Double-drug-resistant bacteria were found in the collection boreholes nine months after injection. Surprisingly, they also appeared in the heater boreholes where the temperature had been sustainably high throughout the test. These bacteria appear to be the species that were injected. The number of double-drug-resistant bacteria that were identified in the collection boreholes increased with time. An apparent homogeneous distribution among the observation boreholes and heater boreholes suggests that a random motion could be the pattern that the bacteria migrated in the block. These observations indicated the possibility of rapid bacterial transport in a thermally perturbed geologic setting

  7. Microbial Community Structure and Function Indicate the Severity of Chromium Contamination of the Yellow River

    Directory of Open Access Journals (Sweden)

    Yaxin Pei

    2018-01-01

    Full Text Available The Yellow River is the most important water resource in northern China. In the recent past, heavy metal contamination has become severe due to industrial processes and other anthropogenic activities. In this study, riparian soil samples with varying levels of chromium (Cr pollution severity were collected along the Gansu industrial reach of the Yellow River, including samples from uncontaminated sites (XC, XGU, slightly contaminated sites (LJX, XGD, and heavily contaminated sites (CG, XG. The Cr concentrations of these samples varied from 83.83 mg⋅kg-1 (XGU to 506.58 mg⋅kg-1 (XG. The chromate [Cr (VI] reducing ability in the soils collected in this study followed the sequence of the heavily contaminated > slightly contaminated > the un-contaminated. Common Cr remediation genes chrA and yieF were detected in the XG and CG samples. qRT-PCR results showed that the expression of chrA was up-regulated four and threefold in XG and CG samples, respectively, whereas the expression of yieF was up-regulated 66- and 7-fold in the same samples after 30 min treatment with Cr (VI. The copy numbers of chrA and yieF didn’t change after 35 days incubation with Cr (VI. The microbial communities in the Cr contaminated sampling sites were different from those in the uncontaminated samples. Especially, the relative abundances of Firmicutes and Bacteroidetes were higher while Actinobacteria was lower in the contaminated group than uncontaminated group. Further, potential indicator species, related to Cr such as Cr-remediation genera (Geobacter, PSB-M-3, Flavobacterium, and Methanosarcina; the Cr-sensitive genera (Skermanella, Iamia, Arthrobacter, and Candidatus Nitrososphaera were also identified. These data revealed that Cr shifted microbial composition and function. Further, Cr (VI reducing ability could be related with the expression of Cr remediation genes.

  8. Bioremediation of diuron contaminated soils by a novel degrading microbial consortium.

    Science.gov (United States)

    Villaverde, J; Rubio-Bellido, M; Merchán, F; Morillo, E

    2017-03-01

    Diuron is a biologically active pollutant present in soil, water and sediments. It is persistent in soil, water and groundwater and slightly toxic to mammals and birds as well as moderately toxic to aquatic invertebrates. Its principal product of biodegradation, 3,4-dichloroaniline, exhibits a higher toxicity than diuron and is also persistent in the environment. On this basis, the objective of the study was to determine the potential capacity of a proposed novel diuron-degrading microbial consortium (DMC) for achieving not only diuron degradation, but its mineralisation both in solution as well as in soils with different properties. The consortium was tested in a soil solution where diuron was the only carbon source, and more than 98.8% of the diuron initially added was mineralised after only a few days. The consortium was composed of three diuron-degrading strains, Arthrobacter sulfonivorans, Variovorax soli and Advenella sp. JRO, the latter had been isolated in our laboratory from a highly contaminated industrial site. This work shows for the first time the potential capacity of a member of the genus Advenella to remediate pesticide-contaminated soils. However, neither of the three strains separately achieved mineralisation (ring- 14 C) of diuron in a mineral medium (MSM) with a trace nutrient solution (NS); combined in pairs, they mineralised 40% of diuron in solution, but the most relevant result was obtained in the presence of the three-member consortium, where complete diuron mineralisation was achieved after only a few days. In the presence of the investigated soils in suspension, the capacity of the consortium to mineralise diuron was evaluated, achieving mineralisation of a wide range of herbicides from 22.9 to 69.0%. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Assessing the hydrocarbon degrading potential of indigenous bacteria isolated from crude oil tank bottom sludge and hydrocarbon-contaminated soil of Azzawiya oil refinery, Libya.

    Science.gov (United States)

    Mansur, Abdulatif A; Adetutu, Eric M; Kadali, Krishna K; Morrison, Paul D; Nurulita, Yuana; Ball, Andrew S

    2014-09-01

    The disposal of hazardous crude oil tank bottom sludge (COTBS) represents a significant waste management burden for South Mediterranean countries. Currently, the application of biological systems (bioremediation) for the treatment of COTBS is not widely practiced in these countries. Therefore, this study aims to develop the potential for bioremediation in this region through assessment of the abilities of indigenous hydrocarbonoclastic microorganisms from Libyan Hamada COTBS for the biotreatment of Libyan COTBS-contaminated environments. Bacteria were isolated from COTBS, COTBS-contaminated soil, treated COTBS-contaminated soil, and uncontaminated soil using Bushnell Hass medium amended with Hamada crude oil (1 %) as the main carbon source. Overall, 49 bacterial phenotypes were detected, and their individual abilities to degrade Hamada crude and selected COBTS fractions (naphthalene, phenanthrene, eicosane, octadecane and hexane) were evaluated using MT2 Biolog plates. Analyses using average well colour development showed that ~90 % of bacterial isolates were capable of utilizing representative aromatic fractions compared to 51 % utilization of representative aliphatics. Interestingly, more hydrocarbonoclastic isolates were obtained from treated contaminated soils (42.9 %) than from COTBS (26.5 %) or COTBS-contaminated (30.6 %) and control (0 %) soils. Hierarchical cluster analysis (HCA) separated the isolates into two clusters with microorganisms in cluster 2 being 1.7- to 5-fold better at hydrocarbon degradation than those in cluster 1. Cluster 2 isolates belonged to the putative hydrocarbon-degrading genera; Pseudomonas, Bacillus, Arthrobacter and Brevundimonas with 57 % of these isolates being obtained from treated COTBS-contaminated soil. Overall, this study demonstrates that the potential for PAH degradation exists for the bioremediation of Hamada COTBS-contaminated environments in Libya. This represents the first report on the isolation of

  10. Biochemistry Oxidation Process for Treatment the Simulation of Organic Liquid Radioactive Waste

    International Nuclear Information System (INIS)

    Gunandjar; Zainus Salimin; Sugeng Purnomo; Ratiko

    2010-01-01

    The nuclear industry activities generate the organic liquid wastes such as detergent waste from laundry, solvent waste of 30% TBP (tri-n-butyl phosphate) in kerosene from purification or recovery of uranium from rejection of nuclear fuel element fabrication, and solvent waste containing D 2 EHPA (di-2-ethyl hexyl phosphoric acid) and TOPO (trioctyl phospine oxide) in kerosene from phosphoric acid purification. The wastes are included in category of the hazard and poison materials which also radioactive, so that the wastes have to be treated to detoxification of the hazard and poison materials and decontamination of the radionuclides. The research of biochemistry oxidation process for treatment the simulation of organic liquid radioactive waste from laundry using mixture of aerobe bacteria of bacillus sp, pseudomonas sp, arthrobacter sp, and aeromonas sp have been carried out. The waste containing detergent 1,496 g/Litre, activity 10 -1 Ci/m 3 , with COD (Chemical Oxygen Demand) 128, BOD (Biological Oxygen Demand) 68 and TSS (Total Suspended Solid) 1000 ppm, it is treated by biochemistry oxidation with addition of bacteria which be fed nutrition of nitrogen and phosphor, and aeration. The result show that the bacteria can decompose the detergent to become carbon dioxyde and water so that can fulfill the quality standard of water group-B with content of BOD and COD are 6 and 10 ppm respectively, the time of decomposition is needed 106 hours to be fulfill the quality standard of water. The longer of process time will give bigger the total solid content in sludge, because the biomass generated from the colony of bacteria which life and dead to so much. (author)

  11. Aerobic biodegradation of a sulfonated phenylazonaphthol dye by a bacterial community immobilized in a multistage packed-bed BAC reactor.

    Science.gov (United States)

    Ruiz-Arias, Alfredo; Juárez-Ramírez, Cleotilde; de los Cobos-Vasconcelos, Daniel; Ruiz-Ordaz, Nora; Salmerón-Alcocer, Angélica; Ahuatzi-Chacón, Deifilia; Galíndez-Mayer, Juvencio

    2010-11-01

    A microbial community able to aerobically degrade the azo dye Acid Orange 7 was selected from riparian or lacustrine sediments collected at sites receiving textile wastewaters. Three bacterial strains, pertaining to the genera Pseudomonas, Arthrobacter, and Rhizobium, constitute the selected community. The biodegradation of AO7 was carried out in batch-suspended cell culture and in a continuously operated multistage packed-bed BAC reactor. The rapid decolorization observed in batch culture, joined to a delay of about 24 h in COD removal and cell growth, suggests that enzymes involved in biodegradation of the aromatic amines generated after AO7 azo-bond cleavage (1-amino-2-naphthol [1-A2N] and 4-aminobenzenesulfonic acid [4-ABS]), are inducible in this microbial consortium. After this presumptive induction period, the accumulated byproducts, measured through COD, were partially metabolized and transformed in cell mass. At all azo dye loading rates used, complete removal of AO7 and 1-A2N was obtained in the multistage packed-bed BAC reactor (PBR).; however, the overall COD (eta ( COD )) and 4-ABS (eta ( ABS )) removal efficiencies obtained in steady state continuous culture were about 90%. Considering the toxicity of 1-A2N, its complete removal has particular relevance. In the first stages of the packed-bed BAC reactor (Fig. 4a-c), major removal was observed. In the last stage, only a slight removal of COD and 4-ABS was obtained. Comparing to several reported studies, the continuously operated multistage packed-bed BAC reactor showed similar or superior results. In addition, the operation of large-packed-bed BAC reactors could be improved by using several shallow BAC bed stages, because the pressure drop caused by bed compaction of a support material constituted by small and fragile particles can be reduced.

  12. Comparative Microbiome Analysis of a Fusarium Wilt Suppressive Soil and a Fusarium Wilt Conducive Soil From the Châteaurenard Region

    Directory of Open Access Journals (Sweden)

    Katarzyna Siegel-Hertz

    2018-04-01

    Full Text Available Disease-suppressive soils are soils in which specific soil-borne plant pathogens cause only limited disease although the pathogen and susceptible host plants are both present. Suppressiveness is in most cases of microbial origin. We conducted a comparative metabarcoding analysis of the taxonomic diversity of fungal and bacterial communities from suppressive and non-suppressive (conducive soils as regards Fusarium wilts sampled from the Châteaurenard region (France. Bioassays based on Fusarium wilt of flax confirmed that disease incidence was significantly lower in the suppressive soil than in the conducive soil. Furthermore, we succeeded in partly transferring Fusarium wilt-suppressiveness to the conducive soil by mixing 10% (w/w of the suppressive soil into the conducive soil. Fungal diversity differed significantly between the suppressive and conducive soils. Among dominant fungal operational taxonomic units (OTUs affiliated to known genera, 17 OTUs were detected exclusively in the suppressive soil. These OTUs were assigned to the Acremonium, Chaetomium, Cladosporium, Clonostachys, Fusarium, Ceratobasidium, Mortierella, Penicillium, Scytalidium, and Verticillium genera. Additionally, the relative abundance of specific members of the bacterial community was significantly higher in the suppressive and mixed soils than in the conducive soil. OTUs found more abundant in Fusarium wilt-suppressive soils were affiliated to the bacterial genera Adhaeribacter, Massilia, Microvirga, Rhizobium, Rhizobacter, Arthrobacter, Amycolatopsis, Rubrobacter, Paenibacillus, Stenotrophomonas, and Geobacter. Several of the fungal and bacterial genera detected exclusively or more abundantly in the Fusarium wilt-suppressive soil included genera known for their activity against F. oxysporum. Overall, this study supports the potential role of known fungal and bacterial genera in Fusarium wilt suppressive soils from Châteaurenard and pinpoints new bacterial and fungal

  13. Characterization of the volatile profile of Antarctic bacteria by using solid-phase microextraction-gas chromatography-mass spectrometry.

    Science.gov (United States)

    Romoli, Riccardo; Papaleo, Maria Cristiana; de Pascale, Donatella; Tutino, Maria Luisa; Michaud, Luigi; LoGiudice, Angelina; Fani, Renato; Bartolucci, Gianluca

    2011-10-01

    Bacteria belonging to the Burkholderia cepacia complex (Bcc) are significant pathogens in Cystic Fibrosis (CF) patients and are resistant to a plethora of antibiotics. In this context, microorganisms from Antarctica are interesting because they produce antimicrobial compounds inhibiting the growth of other bacteria. This is particularly true for bacteria isolated from Antarctic sponges. The aim of this work was to characterize a set of Antarctic bacteria for their ability to produce new natural drugs that could be exploited in the control of infections in CF patients by Bcc bacteria. Hence, 11 bacterial strains allocated to different genera (e.g., Pseudoalteromonas, Arthrobacter and Psychrobacter) were tested for their ability to inhibit the growth of 21 Bcc strains and some other human pathogens. All these bacteria completely inhibited the growth of most, if not all, Bcc strains, suggesting a highly specific activity toward Bcc strains. Experimental evidences showed that the antimicrobial compounds are small volatile organic compounds, and are constitutively produced via an unknown pathway. The microbial volatile profile was obtained by SPME-GC-MS within the m/z interval of 40-450. Solid phase micro extraction technique affords the possibility to extract the volatile compounds in head space with a minimal sample perturbation. Principal component analysis and successive cluster discriminant analysis was applied to evaluate the relationships among the volatile organic compounds with the aim of classifying the microorganisms by their volatile profile. These data highlight the potentiality of Antarctic bacteria as novel sources of antibacterial substances to face Bcc infections in CF patients. Copyright © 2011 John Wiley & Sons, Ltd.

  14. Geomicrobiology of High Level Nuclear Waste-Contaminated Vadose Sediments at the Hanford Site, Washington State

    International Nuclear Information System (INIS)

    Fredrickson, Jim K.; Zachara, John M.; Balkwill, David L.; Kennedy, David W.; Li, Shu-Mei W.; Kostandarithes, Heather M.; Daly, Michael J.; Romine, Margaret F.; Brockman, Fred J.

    2004-01-01

    Sediments from a high-level nuclear waste plume were collected as part of investigations to evaluate the potential fate and migration of contaminants in the subsurface. The plume originated from a leak that occurred in 1962 from a waste tank consisting of high concentrations of alkali, nitrate, aluminate, Cr(VI), 137Cs, and 99Tc. Investigations were initiated to determine the distribution of viable microorganisms in the vadose sediment samples, probe the phylogeny of cultivated and uncultivated members, and evaluate the ability of the cultivated organisms to survive acute doses of ionizing radiation. The populations of viable aerobic heterotrophic bacteria were generally low, from below detection to ∼104 7 CFU g-1 but viable microorganisms were recovered from 11 of 16 samples including several of the most radioactive ones (e.g., > 10 ?Ci/g 137Cs). The isolates from the contaminated sediments and clone libraries from sediment DNA extracts were dominated by members related to known Gram-positive bacteria. Gram-positive bacteria most closely related to Arthrobacter species were the most common isolates among all samples but other high G+C phyla were also represented including Rhodococcus and Nocardia. Two isolates from the second most radioactive sample (>20 ?Ci 137Cs g-1) were closely related to Deinococcus radiodurans and were able to survive acute doses of ionizing radiation approaching 20kGy. Many of the Gram-positive isolates were resistant to lower levels of gamma radiation. These results demonstrate that Gram-positive bacteria, predominantly high G+C phyla, are indigenous to Hanford vadose sediments and some are effective at surviving the extreme physical and chemical stress associated with radioactive waste

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

    Directory of Open Access Journals (Sweden)

    Qiulan Wu

    2018-06-01

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

  16. Application of a new sediment contact test with Myriophyllum aquaticum and of the Aquatic Lemna test to assess the sediment quality of Lake Skadar

    Energy Technology Data Exchange (ETDEWEB)

    Stesevic, D.; Sundic, D.; Mijovic, S. [Montenegro Univ., Podgorica (ME). Faculty of Sciences; Feiler, U.; Heininger, P. [Federal Institute of Hydrology, Koblenz (Germany); Erdinger, L. [Heidelberg Univ. (Germany). Inst. of Hygiene; Seiler, T.B.; Hollert, H. [Heidelberg Univ. (Germany). Dept. of Zoology; RWTH Aachen (Germany). Inst. fuer Umweltforschung - Biologie V

    2007-10-15

    the sediment samples from Radus and Kamenik, whereas the aquatic Lemna test showed inhibition effects for the samples from Sterbeq, Plavnica and Kamice. Data obtained with the newly developed Danio rerio contact test and the Arthrobacter globiformis contact test confirmed the Myriophyllum results. Analyses of the heavy metal content in the sediments revealed low or moderate contamination levels. Correlation analyses between the content of heavy metals in the sediments and growth inhibition of Myriophyllum aquaticum showed a significant correlation between CR concentrations and growth inhibition. Comparable findings are available for a German river system. In contrast, no significant correlation between inhibition rates and concentration of metals could be observed with Lemna minor. (orig.)

  17. Microbial association with the dynamics of particulate organic carbon in response to the amendment of elevated CO2-derived wheat residue into a Mollisol.

    Science.gov (United States)

    Wang, Yanhong; Yu, Zhenhua; Li, Yansheng; Wang, Guanghua; Liu, Junjie; Liu, Judong; Liu, Xiaobing; Jin, Jian

    2017-12-31

    , Actinomadura, Streptomyces and Arthrobacter (P≤0.05). These results imply that the response of the microbial community to the eCO 2 -derived shoot treatment is associated with its contribution to the POC fractions. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Denitrification and Biodiversity of Denitrifiers in a High-Mountain Mediterranean Lake

    Directory of Open Access Journals (Sweden)

    Antonio Castellano-Hinojosa

    2017-10-01

    Full Text Available Wet deposition of reactive nitrogen (Nr species is considered a main factor contributing to N inputs, of which nitrate (NO3− is usually the major component in high-mountain lakes. The microbial group of denitrifiers are largely responsible for reduction of nitrate to molecular dinitrogen (N2 in terrestrial and aquatic ecosystems, but the role of denitrification in removal of contaminant nitrates in high-mountain lakes is not well understood. We have used the oligotrophic, high-altitude La Caldera lake in the Sierra Nevada range (Spain as a model to study the role of denitrification in nitrate removal. Dissolved inorganic Nr concentration in the water column of la Caldera, mainly nitrate, decreased over the ice-free season which was not associated with growth of microbial plankton or variations in the ultraviolet radiation. Denitrification activity, estimated as nitrous oxide (N2O production, was measured in the water column and in sediments of the lake, and had maximal values in the month of August. Relative abundance of denitrifying bacteria in sediments was studied by quantitative polymerase chain reaction of the 16S rRNA and the two phylogenetically distinct clades nosZI and nosZII genes encoding nitrous oxide reductases. Diversity of denitrifiers in sediments was assessed using a culture-dependent approach and after the construction of clone libraries employing the nosZI gene as a molecular marker. In addition to genera Polymorphum, Paracoccus, Azospirillum, Pseudomonas, Hyphomicrobium, Thauera, and Methylophaga, which were present in the clone libraries, Arthrobacter, Burkholderia, and Rhizobium were also detected in culture media that were not found in the clone libraries. Analysis of biological activities involved in the C, N, P, and S cycles from sediments revealed that nitrate was not a limiting nutrient in the lake, allowed N2O production and determined denitrifiers’ community structure. All these results indicate that

  19. Assessing the ecological long-term impact of wastewater irrigation on soil and water based on bioassays and chemical analyses.

    Science.gov (United States)

    Richter, Elisabeth; Hecht, Fabian; Schnellbacher, Nadine; Ternes, Thomas A; Wick, Arne; Wode, Florian; Coors, Anja

    2015-11-01

    The reuse of treated wastewater for irrigation and groundwater recharge can counteract water scarcity and reduce pollution of surface waters, but assessing its environmental risk should likewise consider effects associated to the soil. The present study therefore aimed at determining the impact of wastewater irrigation on the habitat quality of water after soil passage and of soil after percolation by applying bioassays and chemical analysis. Lab-scale columns of four different soils encompassing standard European soil and three field soils of varying characteristics and pre-contamination were continuously percolated with treated wastewater to simulate long-term irrigation. Wastewater and its percolates were tested for immobilization of Daphnia magna and growth inhibition of green algae (Pseudokirchneriella subcapitata) and water lentils (Lemna minor). The observed phytotoxicity of the treated wastewater was mostly reduced by soil passage, but in some percolates also increased for green algae. Chemical analysis covering an extensive set of wastewater-born organic pollutants demonstrated that many of them were considerably reduced by soil passage, particularly through peaty soils. Taken together, these results indicated that wastewater-born phytotoxic substances may be removed by soil passage, while existing soil pollutants (e.g. metals) may leach and impair percolate quality. Soils with and without wastewater irrigation were tested for growth of plants (Avena sativa, Brassica napus) and soil bacteria (Arthrobacter globiformis) and reproduction of collembolans (Folsomia candida) and oligochaetes (Enchytraeus crypticus, Eisenia fetida). The habitat quality of the standard and two field soils appeared to be deteriorated by wastewater percolation for at least one organism (enchytraeids, plants or bacteria), while for two pre-contaminated field soils it also was improved (for plants and/or enchytraeids). Wastewater percolation did not seem to raise soil concentrations

  20. Samanlarda Biyolojik Muamelelerle Lignoselüloz Kompleksin Sindirilebilirliğinin Artırılması

    Directory of Open Access Journals (Sweden)

    Aydan Atalar

    2017-12-01

    Full Text Available Samanların hücre duvarında bulunan lignoselüloz kompleksin parçalanması ile selüloz ve hemiselüloz gibi rumen fermantasyonuyla sindirilebilir fraksiyonlar elde edilir. Rumende sindirilmeyen ligninin biyoteknolojik metotlarla parçalanarak samandan yararlanılabilirliğin artırılması son yıllarda hayvan beslemecilerin odak noktası olan alanlarından birisi olmuştur. Lignoselüloz kompleksin biyolojik metotlarla muamelesinde bakteriler, mantarlar ve bu mikroorganizmalardan elde edilen enzimler kullanılmaktadır. Bakteri muamelesinde Mycobacterium, Arthrobacter ve Flavobacterium türü bakterilerin lignini parçalayabilme özelliğinden yararlanılmaktadır. Enzim muamelesi etkili olmasına rağmen yüksek maliyet nedeniyle uygulamada yer bulamamıştır. Mantar muamelesinde beyaz, kahverengi ve yumuşak çürüme yapan 3 tür mantar kullanılmaktadır. Kahverengi çürükçül mantarlar tercihen selüloz ve hemiselüloza saldırır, ancak lignini parçalayamaz. Beyaz çürükçül mantarlar lignine saldırarak lignol bağları ve aromatik halkayı parçalarlar. Beyaz çürükçül mantarlar selülaz, ksilanaz gibi hidrolitik enzimlerle polisakkaritleri ve lignin peroksidaz ve lakkaz gibi oksidatif ligninolitik enzimlerle lignini parçalarlar. Lignoselülozik materyalleri en iyi parçalayabilen mikroorganizmaların mantarlar olması ve maliyetin düşük olması nedeniyle özellikle beyaz çürükçül mantarların uygulama potansiyeli bulunmaktadır. Bu bildiride biyoçeşitliliğin sağladığı avantajla biyolojik metotlarla samanların sindirilebilirliğinin artırılması tartışılacaktır.

  1. Canola Root–Associated Microbiomes in the Canadian Prairies

    Directory of Open Access Journals (Sweden)

    Chih-Ying Lay

    2018-06-01

    Full Text Available Canola is one of the most economically important crops in Canada, and the root and rhizosphere microbiomes of a canola plant likely impact its growth and nutrient uptake. The aim of this study was to determine whether canola has a core root microbiome (i.e., set of microbes that are consistently selected in the root environment, and whether this is distinct from the core microbiomes of other crops that are commonly grown in the Canadian Prairies, pea, and wheat. We also assessed whether selected agronomic treatments can modify the canola microbiome, and whether this was associated to enhanced yield. We used a field experiment with a randomized complete block design, which was repeated at three locations across the canola-growing zone of Canada. Roots and rhizosphere soil were harvested at the flowering stage of canola. We separately isolated total extractable DNA from plant roots and from adjacent rhizosphere soil, and constructed MiSeq amplicon libraries for each of 60 samples, targeting bacterial, and archaeal 16S rRNA genes and the fungal ITS region. We determined that the microbiome of the roots and rhizosphere of canola was consistently different from those of wheat and pea. These microbiomes comprise several putative plant-growth-promoting rhizobacteria, including Amycolatopsis sp., Serratia proteamaculans, Pedobacter sp., Arthrobacter sp., Stenotrophomonas sp., Fusarium merismoides, and Fusicolla sp., which correlated positively with canola yield. Crop species had a significant influence on bacterial and fungal assemblages, especially within the roots, while higher nutrient input or seeding density did not significantly alter the global composition of bacterial, fungal, or archaeal assemblages associated with canola roots. However, the relative abundance of Olpidium brassicae, a known pathogen of members of the Brassicaceae, was significantly reduced in the roots of canola planted at higher seeding density. Our results suggest that

  2. Structural study of phosphomannan of yeast-form cells of Candida albicans J-1012 strain with special reference to application of mild acetolysis.

    Science.gov (United States)

    Kobayashi, H; Shibata, N; Mitobe, H; Ohkubo, Y; Suzuki, S

    1989-08-01

    Structural analysis of the phosphomannan isolated from yeast-form cells of a pathogenic yeast, Candida albicans J-1012 strain, was conducted. Treatment of this phosphomannan (Fr. J) with 10 mM HCl at 100 degrees C for 60 min gave a mixture of beta-1,2-linked manno-oligosaccharides, from tetraose to biose plus mannose, and an acid-stable mannan moiety (Fr. J-a), which was then acetolyzed by means of an acetolysis medium, 100:100:1 (v/v) mixture of (CH3CO)2O, CH3COOH, and H2SO4, at 40 degrees C for 36 h in order to avoid cleavage of the beta-1,2 linkage. The resultant manno-oligosaccharide mixture was fractionated on a column of Bio-Gel P-2 to yield insufficiently resolved manno-oligosaccharide fractions higher than pentaose and lower manno-oligosaccharides ranging from tetraose to biose plus mannose. The higher manno-oligosaccharide fraction was then digested with the Arthrobacter GJM-1 alpha-mannosidase in order to cleave the enzyme-susceptible alpha-1,2 and alpha-1,3 linkages, leaving manno-oligosaccharides containing the beta-1,2 linkage at their nonreducing terminal sites, Manp beta 1----2Manp alpha 1----2Manp alpha 1----2Manp alpha 1----2Man, Manp beta 1----2Manp beta 1----2Manp alpha 1----2Manp alpha 1---- 2Manp alpha 1----2Man, and Manp beta 1----2Manp beta 1----2Manp beta 1----2Manp alpha 1---- 2Manp alpha 1----2Manp alpha 1----2Man. However, the result of acetolysis of Fr. J-a by means of a 10:10:1 (v/v) mixture of (CH3CO)2O, CH3COOH, and H2SO4 at 40 degrees C for 13 h was significantly different from that obtained by the mild acetolysis method; i.e., the amount of mannose was apparently larger than that formed by the mild acetolysis method. In summary, a chemical structure for Fr. J as a highly branched mannan containing 14 different branching moieties was proposed.

  3. Comparative Metatranscriptomics of Wheat Rhizosphere Microbiomes in Disease Suppressive and Non-suppressive Soils for Rhizoctonia solani AG8

    Directory of Open Access Journals (Sweden)

    Helen L. Hayden

    2018-05-01

    Full Text Available The soilborne fungus Rhizoctonia solani anastomosis group (AG 8 is a major pathogen of grain crops resulting in substantial production losses. In the absence of resistant cultivars of wheat or barley, a sustainable and enduring method for disease control may lie in the enhancement of biological disease suppression. Evidence of effective biological control of R. solani AG8 through disease suppression has been well documented at our study site in Avon, South Australia. A comparative metatranscriptomic approach was applied to assess the taxonomic and functional characteristics of the rhizosphere microbiome of wheat plants grown in adjacent fields which are suppressive and non-suppressive to the plant pathogen R. solani AG8. Analysis of 12 rhizosphere metatranscriptomes (six per field was undertaken using two bioinformatic approaches involving unassembled and assembled reads. Differential expression analysis showed the dominant taxa in the rhizosphere based on mRNA annotation were Arthrobacter spp. and Pseudomonas spp. for non-suppressive samples and Stenotrophomonas spp. and Buttiauxella spp. for the suppressive samples. The assembled metatranscriptome analysis identified more differentially expressed genes than the unassembled analysis in the comparison of suppressive and non-suppressive samples. Suppressive samples showed greater expression of a polyketide cyclase, a terpenoid biosynthesis backbone gene (dxs and many cold shock proteins (csp. Non-suppressive samples were characterised by greater expression of antibiotic genes such as non-heme chloroperoxidase (cpo which is involved in pyrrolnitrin synthesis, and phenazine biosynthesis family protein F (phzF and its transcriptional activator protein (phzR. A large number of genes involved in detoxifying reactive oxygen species (ROS and superoxide radicals (sod, cat, ahp, bcp, gpx1, trx were also expressed in the non-suppressive rhizosphere samples most likely in response to the infection of wheat

  4. Recovery and identification of bacterial DNA from illicit drugs.

    Science.gov (United States)

    Cho, Kaymann T; Richardson, Michelle M; Kirkbride, K Paul; McNevin, Dennis; Nelson, Michelle; Pianca, Dennis; Roffey, Paul; Gahan, Michelle E

    2014-02-01

    Bacterial infections, including Bacillus anthracis (anthrax), are a common risk associated with illicit drug use, particularly among injecting drug users. There is, therefore, an urgent need to survey illicit drugs used for injection for the presence of bacteria and provide valuable information to health and forensic authorities. The objectives of this study were to develop a method for the extraction of bacterial DNA from illicit drugs and conduct a metagenomic survey of heroin and methamphetamine seized in the Australian Capital Territory during 2002-2011 for the presence of pathogens. Trends or patterns in drug contamination and their health implications for injecting drug users were also investigated. Methods based on the ChargeSwitch(®)gDNA mini kit (Invitrogen), QIAamp DNA extraction mini kit (QIAGEN) with and without bead-beating, and an organic phenol/chloroform extraction with ethanol precipitation were assessed for the recovery efficiency of both free and cellular bacterial DNA. Bacteria were identified using polymerase chain reaction and electrospray ionization-mass spectrometry (PCR/ESI-MS). An isopropanol pre-wash to remove traces of the drug and diluents, followed by a modified ChargeSwitch(®) method, was found to efficiently lyse cells and extract free and cellular DNA from Gram-positive and Gram-negative bacteria in heroin and methamphetamine which could then be identified by PCR/ESI-MS. Analysis of 12 heroin samples revealed the presence of DNA from species of Comamonas, Weissella, Bacillus, Streptococcus and Arthrobacter. No organisms were detected in the nine methamphetamine samples analysed. This study develops a method to extract and identify Gram-positive and Gram-negative bacteria from illicit drugs and demonstrates the presence of a range of bacterial pathogens in seized drug samples. These results will prove valuable for future work investigating trends or patterns in drug contamination and their health implications for injecting drug

  5. Denitrification and Biodiversity of Denitrifiers in a High-Mountain Mediterranean Lake

    Science.gov (United States)

    Castellano-Hinojosa, Antonio; Correa-Galeote, David; Carrillo, Presentación; Bedmar, Eulogio J.; Medina-Sánchez, Juan M.

    2017-01-01

    Wet deposition of reactive nitrogen (Nr) species is considered a main factor contributing to N inputs, of which nitrate (NO3−) is usually the major component in high-mountain lakes. The microbial group of denitrifiers are largely responsible for reduction of nitrate to molecular dinitrogen (N2) in terrestrial and aquatic ecosystems, but the role of denitrification in removal of contaminant nitrates in high-mountain lakes is not well understood. We have used the oligotrophic, high-altitude La Caldera lake in the Sierra Nevada range (Spain) as a model to study the role of denitrification in nitrate removal. Dissolved inorganic Nr concentration in the water column of la Caldera, mainly nitrate, decreased over the ice-free season which was not associated with growth of microbial plankton or variations in the ultraviolet radiation. Denitrification activity, estimated as nitrous oxide (N2O) production, was measured in the water column and in sediments of the lake, and had maximal values in the month of August. Relative abundance of denitrifying bacteria in sediments was studied by quantitative polymerase chain reaction of the 16S rRNA and the two phylogenetically distinct clades nosZI and nosZII genes encoding nitrous oxide reductases. Diversity of denitrifiers in sediments was assessed using a culture-dependent approach and after the construction of clone libraries employing the nosZI gene as a molecular marker. In addition to genera Polymorphum, Paracoccus, Azospirillum, Pseudomonas, Hyphomicrobium, Thauera, and Methylophaga, which were present in the clone libraries, Arthrobacter, Burkholderia, and Rhizobium were also detected in culture media that were not found in the clone libraries. Analysis of biological activities involved in the C, N, P, and S cycles from sediments revealed that nitrate was not a limiting nutrient in the lake, allowed N2O production and determined denitrifiers’ community structure. All these results indicate that denitrification could be a

  6. Phylogenetic diversity and biological activity of culturable Actinobacteria isolated from freshwater fish gut microbiota.

    Science.gov (United States)

    Jami, Mansooreh; Ghanbari, Mahdi; Kneifel, Wolfgang; Domig, Konrad J

    2015-06-01

    The diversity of Actinobacteria isolated from the gut microbiota of two freshwater fish species namely Schizothorax zarudnyi and Schizocypris altidorsalis was investigated employing classical cultivation techniques, repetitive sequence-based PCR (rep-PCR), partial and full 16S rDNA sequencing followed by phylogenetic analysis. A total of 277 isolates were cultured by applying three different agar media. Based on rep-PCR profile analysis a subset of 33 strains was selected for further phylogenetic investigations, antimicrobial activity testing and diversity analysis of secondary-metabolite biosynthetic genes. The identification based on 16S rRNA gene sequencing revealed that the isolates belong to eight genera distributed among six families. At the family level, 72% of the 277 isolates belong to the family Streptomycetaceae. Among the non-streptomycetes group, the most dominant group could be allocated to the family of Pseudonocardiaceae followed by the members of Micromonosporaceae. Phylogenetic analysis clearly showed that many of the isolates in the genera Streptomyces, Saccharomonospora, Micromonospora, Nocardiopsis, Arthrobacter, Kocuria, Microbacterium and Agromyces formed a single and distinct cluster with the type strains. Notably, there is no report so far about the occurrence of these Actinobacteria in the microbiota of freshwater fish. Of the 33 isolates, all the strains exhibited antibacterial activity against a set of tested human and fish pathogenic bacteria. Then, to study their associated potential capacity to synthesize diverse bioactive natural products, diversity of genes associated with secondary-metabolite biosynthesis including PKS I, PKS II, NRPS, the enzyme PhzE of the phenazine pathways, the enzyme dTGD of 6-deoxyhexoses glycosylation pathway, the enzyme Halo of halogenation pathway and the enzyme CYP in polyene polyketide biosynthesis were investigated among the isolates. All the strains possess at least two types of the investigated

  7. Microbial communities in bentonite formations and their interactions with uranium

    International Nuclear Information System (INIS)

    López-Fernández, Margarita; Fernández-Sanfrancisco, Omar; Moreno-García, Alberto; Martín-Sánchez, Inés; Sánchez-Castro, Iván; Merroun, Mohamed Larbi

    2014-01-01

    Highlights: • Microbial diversity of Spanish bentonites was studied. • High number of aerobe and facultative anaerobe microbes were isolated from bentonites. • Natural bentonite microbes are able to tolerate high U concentrations. • U is immobilized by the cells of the strain Rhodotorula mucilaginosa BII-R8 as U(VI) phosphates. - Abstract: A reliable performance assessment of deep geological disposal of nuclear waste depends on better knowledge of radionuclide interactions with natural microbes of geological formations (granitic rock, clay, salts) used to host these disposal systems. In Spain, clay deposits from Cabo de Gata region, Almeria, are investigated for this purpose. The present work characterizes the culture-dependent microbial diversity of two bentonite samples (BI and BII) recovered from Spanish clay deposits. The evaluation of aerobe and facultative anaerobe microbial populations shows the presence of a high number of cultivable bacteria (e.g. Stenotrophomonas, Micrococcus, Arthrobacter, Kocuria, Sphingomonas, Bacillus, Pseudomonas, etc.) affiliated to three phyla Proteobacteria, Actinobacteria, and Firmicutes. In addition, a pigmented yeast strain BII-R8 related to Rhodotorula mucilaginosa was also recovered from these formations. The minimal inhibitory concentrations of uranium for the growth of these natural isolates were found to range from 4 to 10.0 mM. For instance, strain R. mucilaginosa BII-R8 was shown to tolerate up to 8 mM of U. Flow cytometry studies indicated that the high U tolerance of this yeast isolate is a biologically mediated process. Microscopically dense intracellular and cell wall-bound precipitates were observed by Scanning Transmission Electron Microscopy-High-Angle Annular Dark-Field (STEM-HAADF). Energy Dispersive X-ray (EDX) element-distribution maps showed the presence of U and P within these accumulates, indicating the ability of cells to precipitate U as U(VI) phosphate minerals. Fundamental understanding of the

  8. Microbial communities in bentonite formations and their interactions with uranium

    Energy Technology Data Exchange (ETDEWEB)

    López-Fernández, Margarita; Fernández-Sanfrancisco, Omar; Moreno-García, Alberto; Martín-Sánchez, Inés; Sánchez-Castro, Iván; Merroun, Mohamed Larbi, E-mail: merroun@ugr.es

    2014-10-15

    Highlights: • Microbial diversity of Spanish bentonites was studied. • High number of aerobe and facultative anaerobe microbes were isolated from bentonites. • Natural bentonite microbes are able to tolerate high U concentrations. • U is immobilized by the cells of the strain Rhodotorula mucilaginosa BII-R8 as U(VI) phosphates. - Abstract: A reliable performance assessment of deep geological disposal of nuclear waste depends on better knowledge of radionuclide interactions with natural microbes of geological formations (granitic rock, clay, salts) used to host these disposal systems. In Spain, clay deposits from Cabo de Gata region, Almeria, are investigated for this purpose. The present work characterizes the culture-dependent microbial diversity of two bentonite samples (BI and BII) recovered from Spanish clay deposits. The evaluation of aerobe and facultative anaerobe microbial populations shows the presence of a high number of cultivable bacteria (e.g. Stenotrophomonas, Micrococcus, Arthrobacter, Kocuria, Sphingomonas, Bacillus, Pseudomonas, etc.) affiliated to three phyla Proteobacteria, Actinobacteria, and Firmicutes. In addition, a pigmented yeast strain BII-R8 related to Rhodotorula mucilaginosa was also recovered from these formations. The minimal inhibitory concentrations of uranium for the growth of these natural isolates were found to range from 4 to 10.0 mM. For instance, strain R. mucilaginosa BII-R8 was shown to tolerate up to 8 mM of U. Flow cytometry studies indicated that the high U tolerance of this yeast isolate is a biologically mediated process. Microscopically dense intracellular and cell wall-bound precipitates were observed by Scanning Transmission Electron Microscopy-High-Angle Annular Dark-Field (STEM-HAADF). Energy Dispersive X-ray (EDX) element-distribution maps showed the presence of U and P within these accumulates, indicating the ability of cells to precipitate U as U(VI) phosphate minerals. Fundamental understanding of the

  9. Comunidades microbianas, atividade enzimática e fungos micorrízicos em solo rizosférico de "Landfarming" de resíduos petroquímicos Microbial communities, enzymatic activity and mycorrhizal fungi in rhizospheric soil used for Landfarming of Petrochemical Waste

    Directory of Open Access Journals (Sweden)

    André Shigueyoshi Nakatani

    2008-08-01

    bacteriana diferente do solo sem plantas. As bactérias degradadoras de antraceno isoladas apresentaram relação filogenética com os gêneros Streptomyces, Nocardioides, Arthrobacter, Pseudoxanthomonas e com gêneros não identificados das famílias Cellulomonadaceae, Xanthomonadaceae e Rhodobacteraceae, sendo quatro destes isolados pertencentes aos actinomicetos. Apenas Nocardioides e o gênero relacionado com a família Cellulomonadaceae foram relatados em áreas brasileiras contaminadas com hidrocarbonetos de petróleo. Conclui-se que as plantas estimulam o aumento da densidade de células bacterianas e alteram a comunidade microbiana do solo de "landfarming" de resíduo petroquímico.The presence of plants stimulates soil microbiota, which may contribute to soil remediation. It is of great interest to quantify these effects on heterotrophic microorganisms due to their practical and ecological relevance. The following factors were evaluated: bacterial cell density, enzymatic activity, bacterial community structure and the spontaneous occurrence of arbuscular mycorrhizal fungi (AMF in the plant rhizosphere in an area of land farming of petrochemical wastes, using a rhizospheric soil under five plants and control soil without plants. The following evaluation methods were applied: microorganism plate counts, molecular methods, denaturing gradient gel electrophoresis (DGGE and gene sequencing, colorimetric methods for enzymes and percentage of root colonization, counting and identification of AMF spores. Total and anthracene degrading microbial density were stimulated by the presence of plants, with average counts of 1.5x10(6 and 2.2x10(6 CFU g dry soil-1, respectively, while soil without plants soil counts were 5.7x10(5 and 2.9x10(5 CFU g dry soil-1 for the respective microbial groups. The species Bidens pilosa and Eleusine indica had the highest stimulatory effects on microbial density. No stimulating plant effects of soil enzymatic activity were verified. Root

  10. Chromatographic profiles of blood plasma free oligosaccharides in patients with cardiovascular disease

    Directory of Open Access Journals (Sweden)

    I. U. Pismenetskaya

    2015-03-01

    Full Text Available Free oligosaccharides (FOS are unbound structural analogs of glycans of glycoconjugates. There are several sources of them inside the cell: 1 multistep pathways of N-glycosylation, 2 the cell quality control and endoplastic reticulum-associated degradation of mis-glycosylated and/or misfolded glycoproteins, 3 lysosomal degradation of mature glycoconjugates. Some of these FOS are the earliest indicators of potential glycosylation alterations that would be revealed in the course of the cell quality control and the endoplastic reticulum-associated degradation. Ischemia and hypertension cause stress of intracellular organelles leading to disruption of their functions. The main objective of the work was the characterization of free oligosaccharides (FOS in plasma obtained from patients with cardiovascular diseases compared to those from healthy subjects to evaluate the potential of these compounds for diagnostics. Chromatographic profiles of FOS composed of 4–12 monosaccharides were obtained and analyzed for quantitative and qualitative differences between the samples. After plasma deproteinization and FOS purification the oligosaccharides were labelled with anthranilic acid (2-AA, separated into the neutral and charged with QAE Sephadex (Q25-120 chromatography and analysed using high-performance liquid chromatography (HPLC. Glucose unit values were determined following comparison with a 2-AA-labelled glucose oligomer ladder derived from a partial hydrolysate of dextran as an external standard. The data were collected and processed using Empower software. The charged FOS were digested with the sialidase from Arthrobacter ureafaciens. 2-AA – labelled free oligosaccharides from transferrin were used as an external standard for the structure decoding. The profiles obtained were compared with intracellular free oligosaccharides of known structures and with the glycan structures and their descriptions in the databases GlycoBase and EUROCarbDB. These

  11. Proposal of concentration limits for determining the hazard property HP 14 for waste using ecotoxicological tests.

    Science.gov (United States)

    Hennebert, Pierre

    2018-04-01

    substances), 37 were classified H (64%) and 21 were classified NH (36%). These concentration limits can be refined with the method proposed here, as soon as additional data of NH waste (by list and by composition) are available. The test battery (without options) and the concentration limits (in percent of waste in the culture/dilution medium) proposed are the following: A waste is hazardous for HP 14 'Ecotoxic' if the concentration of waste (eluate or solid) in the culture/dilution medium producing 50% of biological effect relative to the control EC 50 -30 min of Vibrio fischeri (EN ISO 11348-3) is lower than 15.8%, or if the EC 50 -72 h of Pseudokirchneriella subcapitata (EN ISO 8692) is lower than 7.03%, or if the EC 50 -48 h of Daphnia magna (EN ISO 6341) is lower than 7.95%, or if the EC 50 -6h of Arthrobacter globiformis (ISO 18187) is lower than 2.25%, or if the EC 50 -14d of Brassica rapa (EN ISO 11269-2) is lower than 13.7%, or if the EC 50 -48 h of Eisenia fetida avoidance test (ISO 17512-1) is lower than 3.75%. These CLs range between 2% and 16%, which is in line with the typically 10% concentration proposed without validation. To fix regulatory concentration limits, the regulators can use these CLs and the uncertainty of the ecotoxicological tests (standard deviation of inter-laboratory reproducibility typically of 25% of the mean, as published in the standards). Classification of waste for HP 14 with these tests and concentration limits will agree with the European List of Waste. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Influence of biocrusts coverage on microbial communities from underlying arid lands soils

    Science.gov (United States)

    Anguita-Maeso, Manuel; Miralles*, Isabel; van Wesemael, Bas; Lázaro, Roberto; Ortega, Raúl; García-Salcedo, José Antonio; Soriano**, Miguel

    2017-04-01

    position of biocrust cover (1.59E+12 in L. issidiata, in 1.19E+12 D. diacapsis and S. lentigera, 2.71E+12 in cyanobacteria and 2.15E+12 in incipient colonization by cyanobacteria) to the unfavourable state (8.94E+11 in L. issidiata, in 7.62E+11 D. diacapsis and S. lentigera, 1.30E+12 in cyanobacteria and 5.49E+11 in incipient cyanobacteria biocrust). Clearly, it is observed that the percentage of biocrusts coverage influences the number of bacteria and fungi in underlying biocrusts soils. Furthermore, metagenomic and statistical analysis displays the variability of microbial communities depending on the percentage of biocrusts coverage. Segetibacter (5.28%), Rubrobacter (3.12%) and Blastopirellulla (0.77%) tend to be present in advantageous state of biocrust coverage while Rubellimicrobium (1.17%), Arthrobacter (0.35%) and Gp16 (0.65%) lean towards the adverse positions. Our results concluded with the idea that different microorganisms have a tendency to be located at certain percentage of biocrust coverage, which playing an essential role in the maintenance of microbial communities structure in underlying soils. (*) Financial support by Marie Curie Intra-European Fellowship (FP7-577 PEOPLE-2013-IEF, Proposal n° 623393) and (**) by the Ministerio de Economía y Competitividad (MINECO) cofinanced with FEDER funds (project CGL2015-71709-R) is acknowledged.

  13. Biofilms and planktonic cells of Deinococcus geothermalis in extreme environments

    Science.gov (United States)

    Panitz, Corinna; Reitz, Guenther; Rabbow, Elke; Rettberg, Petra; Flemming, Hans-Curt; Wingender, Jost; Froesler, Jan

    radiation. D. geothermalis besides others, like co-cultures of Halomonas muralis and Halococcus morrhuae, Bacillus horneckiae, Chroococcidiopsis CCMEE 029 and Streptomyces + Polaromonas and Arthrobacter strains from volcanic rocks, was involved in the several preparatory test runs at the Planetary and Space Simulation facilities at the German Aerospace Center in Cologne. Results of the already carried out EVTs (Experiment Verification Test) and the SVT (Science verification test) as EXPOSE-R2 mission pre-paration tests, where investigated parameters like dehydration, temperature extremes, extraterrestrial UV radiation, simulated Martian atmosphere, and a Mars-like UV climate were tested individually as well as in combination will be presented. Following exposure to the parameters listed above, the survival of both biofilms and planktonic cells of D. geothermalis was assessed in terms of (i) culturability by colony counts on R2A medium, (ii) membrane integrity by using the Live/Dead differential staining kit, (iii) ATP content by using a commercial luminometric assay, and (iv) the presence of 16S rRNA by fluorescence in situ hybridization. So far, the results suggest that Deinococcus geothermalis remains viable in the desiccated state over weeks to months, whereas culturability, intracellular ATP levels, and membrane integrity were preserved in biofilm cells at a significantly higher level than in planktonic cells. Furthermore, cells of both sample types were able to survive simulated space and Martian conditions and showed high resistance after irradiation with monochromatic and polychromatic UV. The results will contribute to the fundamental understanding of the opportunities and limitations of viability of microorganisms organized in biofilms or as planktonic cells under the extreme environ-mental conditions of space or other planets.

  14. Effects of Different Sources of Nutrition on Quantitative and Qualitative Characteristics of Lycopersicon esculentum under Ecological Cropping System

    Directory of Open Access Journals (Sweden)

    M.B. Amiri

    2016-02-01

    Full Text Available Introduction: Increasing usage of chemical fertilizers imposes irreparable damages to the environment. Disadvantages of chemical fertilizers has led to more attention to the application of organic fertilizers and manures. The use of organic fertilizers and livestock, especially in nutrient poor soils, it is necessary to maintain soil quality. Plant growth promoting rhizobacteria (PGPR occupy the rhizosphere of many plant species and have beneficial effects on the host plant. They may influence the plant in a direct or indirect manner. A direct mechanism would be to increase plant growth by supplying the plant with nutrients and hormones. Indirect mechanisms on the otherhand, include, reduced susceptibility to diseases, and activing a form of defese referred to as induces systematic resistance. Examples of bacteria which have been found to enhance plant growth, include Pseudomonas, Enterobacter and Arthrobacter. Biofertilizers contain organic compounds that increase soil fertility either directly or as a result of their decay (9, 10. Tomato (Lycopersicon esculentum L. belongs to the nightshade family, Solanaceae. The plant typically grow 1-3 meters in height and a weak stem. It is a perennial in its native habitat, although often grown outdoors in temperate climates as an annual. An average common tomato weighs approximately 100 grams. Tomatoes contain the carotene lycopene, one of the most powerful natural antioxidants. In some studies, lycopene, especially in cooked tomatoes, has been found to help prevent prostate cancer. Lycopene has also been shown to improve the skin’s ability to protect against harmful UV rays. Tomatoes might help in managing human neurodegenerative diseases. The lycopene has no effect on the risk of developing diabetes, but may help relieve the oxidative stress of people who already have diabetes. The purpose of this study was the possibility of replacing chemical fertilizers with biofertilizers, reducing production

  15. Molecular biomonitoring during rhizoremediation of oil-contaminated soil

    Energy Technology Data Exchange (ETDEWEB)

    Jussila, M.

    2006-07-01

    the xylE gene were designed for TOL plasmid detection. Amplified enzyme-coding DNA restriction analysis (AEDRA) with AluI was used to profile both TOL plasmids (xylE primers) and, in general, aromatics-degrading plasmids (C230 primers). The sensitivity of the direct monitoring of TOL plasmids in soil was enhanced by nested C23O-xylE-PCR. Rhizosphere bacteria were isolated from the greenhouse and field lysimeter experiments. High genetic diversity was observed among the 50 isolated, m-toluate tolerating rhizosphere bacteria in the form of five major lineages of the Bacteria domain. Gram-positive Rhodococcus, Bacillus and Arthrobacter and gram-negative Pseudomonas were the most abundant genera. The inoculum Pseudomonas putida PaW85/pWW0 was not found in the rhizosphere samples. Even if there were no ecological niches available for the bioaugmentation bacterium itself, its conjugative catabolic plasmid might have had some additional value for other bacterial species and thus, for rhizoremediation. Only 10 to 20% of the isolated, m-toluate tolerating bacterial strains were also able to degrade m-toluate. TOL plasmids were a major group of catabolic plasmids among these bacteria. The ability to degrade m-toluate by using enzymes encoded by a TOL plasmid was detected only in species of the genus Pseudomonas, and the best m-toluate degraders were these Pseudomonas species. Strain-specific differences in degradation abilities were found for P.oryzihabitans and P. migulae: some of these strains harbored a TOL plasmid - a new finding observed in this work, indicating putative horizontal plasmid transfer in the rhizosphere. Three aspects of the rhizosphere effect of G. orientalis were manifested in oil-contaminated soil in the field: (1) G. orientalis and Pseudomonas bioaugmentation increased the amount of rhizosphere bacteria. G. orientalis especially together with Pseudomonas bioaugmentation increased the numbers of m-toluate utilizing and catechol positive bacteria indicating