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Sharavin DY, Belyaeva PG. Biotechnological potential of psychrotolerant methylobacteria isolated from biotopes of Antarctic oases. Arch Microbiol 2024; 206:323. [PMID: 38907777 DOI: 10.1007/s00203-024-04056-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Accepted: 06/16/2024] [Indexed: 06/24/2024]
Abstract
Ten strains of psychrotolerant methylotrophic bacteria were isolated from the samples collected in Larsemann and Bunger Hills (Antarctica). Most of the isolates are assigned to the genus Pseudomonas, representatives of the genera Janthinobacterium, Massilia, Methylotenera and Flavobacterium were also found. Majority of isolates were able to grow on a wide range of sugars, methylamines and other substrates. Optimal growth temperatures for the isolated strains varied from 6 °C to 28 °C. The optimal concentration of NaCl was 0.5-2.0%. The optimal pH values of the medium were 6-7. It was found that three strains synthesized indole-3-acetic acid on a medium with L-tryptophan reaching 11-12 μg/ml. The values of intracellular carbohydrates in several strains exceeded 50 μg/ml. Presence of calcium-dependent and lanthanum-dependent methanol dehydrogenase have been shown for some isolates. Strains xBan7, xBan20, xBan37, xBan49, xPrg27, xPrg48, xPrg51 showed the presence of free amino acids. Bioprospection of Earth cryosphere for such microorganisms has a potential in biotechnology.
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Affiliation(s)
- Dmitry Yuryevich Sharavin
- Laboratory of Cellular Immunology and Nanobiotechnology, Institute of Ecology and Genetics of Microorganisms (IEGM), 13, Golev st., Perm, 614081, Russia.
| | - Polina Gennadievna Belyaeva
- Laboratory of Cellular Immunology and Nanobiotechnology, Institute of Ecology and Genetics of Microorganisms (IEGM), 13, Golev st., Perm, 614081, Russia
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Lick S, Wibberg D, Busche T, Blom J, Grimmler C, Goesmann A, Kalinowski J. Pseudomonas kulmbachensis sp. nov. and Pseudomonas paraveronii sp. nov., originating from chilled beef and chicken breast. Int J Syst Evol Microbiol 2024; 74. [PMID: 38587505 DOI: 10.1099/ijsem.0.006293] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/09/2024] Open
Abstract
By investigating wet and dry age-related ripening of beef, Pseudomonas strains V3/3/4/13T and V3/K/3/5T were isolated. Strain V3/3/4/13T exhibited more than 99 % 16S rRNA gene-based similarity to Pseudomonas fragi and other members of this group, while isolate V3/K/3/5T was very close to Pseudomonas veronii and a number of relatives within the Pseudomonas fluorescens group. Additional comparisons of complete rpoB sequences and draft genomes allowed us to place isolate V3/3/4/13T close to Pseudomonas deceptionensis DSM 26521T. In the case of V3/K/3/5T the closest relative was P. veronii DSM 11331T. Average nucleotide identity (ANIb) and digital DNA-DNA hybridization (dDDH) values calculated from the draft genomes of V3/3/4/13T and P. deceptionensis DSM 26521T were 88.5 and 39.8 %, respectively. For V3/K/3/5T and its closest relative P. veronii DSM 11331T, the ANIb value was 95.1 % and the dDDH value was 60.7 %. The DNA G+C contents of V3/3/4/13T and V3/K/3/5T were 57.4 and 60.8 mol%, respectively. Predominant fatty acids were C16 : 0, C18 : 1 ω7c, C17 : 0 cyclo and summed feature C16 : 1 ω7ct/C15 : 0 iso 2OH. The main respiratory quinones were Q9, with minor proportions of Q8 and, in the case of V3/K/3/5T, additional Q10. The main polar lipids were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine and, in the case of V3/K/3/5T, additional phosphatidylcholine. Based on the combined data, isolates V3/3/4/13T and V3/K/3/5T should be considered as representatives of two novel Pseudomonas species. The type strain of the newly proposed Pseudomonas kulmbachensis sp. nov. is V3/3/4/13T (=DSM 113654T=LMG 32520T), a second strain belonging to the same species is FLM 004-28 (=DSM 113604=LMG 32521); the type strain for the newly proposed Pseudomonas paraveronii sp. nov. is V3/K/3/5T (=DSM 113573T=LMG 32518T) with a second isolate FLM 11 (=DSM 113572=LMG 32519).
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Affiliation(s)
- Sonja Lick
- Max Rubner-Institut, Federal Research Institute for Nutrition and Food, Department of Safety and Quality of Meat, E.-C.-Baumann Straße 20, D-95326 Kulmbach, Germany
| | - Daniel Wibberg
- Center for Biotechnology - CeBiTec, Bielefeld University, Universitätsstraße 27, D-33615 Bielefeld, Germany
- ELIXIR DE Administration Office, Institute of Bio- and Geosciences IBG-5, Forschungszentrum Jülich GmbH - Branch office Bielefeld, Universitätsstraße 27, D-33615 Bielefeld, Germany
| | - Tobias Busche
- Center for Biotechnology - CeBiTec, Bielefeld University, Universitätsstraße 27, D-33615 Bielefeld, Germany
- Medical School East Westphalia-Lippe, Bielefeld University, Universitätsstraße 27, D-33615 Bielefeld, Germany
| | - Jochen Blom
- Bioinformatics and Systems Biology, Justus-Liebig-University Gießen, Ludwigsstraße 23, D-35392 Gießen, Germany
| | - Christina Grimmler
- Max Rubner-Institut, Federal Research Institute for Nutrition and Food, Department of Safety and Quality of Meat, E.-C.-Baumann Straße 20, D-95326 Kulmbach, Germany
| | - Alexander Goesmann
- Bioinformatics and Systems Biology, Justus-Liebig-University Gießen, Ludwigsstraße 23, D-35392 Gießen, Germany
| | - Jörn Kalinowski
- Center for Biotechnology - CeBiTec, Bielefeld University, Universitätsstraße 27, D-33615 Bielefeld, Germany
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Hassan Z, Westerhoff HV. Arsenic Contamination of Groundwater Is Determined by Complex Interactions between Various Chemical and Biological Processes. TOXICS 2024; 12:89. [PMID: 38276724 PMCID: PMC11154318 DOI: 10.3390/toxics12010089] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2023] [Revised: 01/03/2024] [Accepted: 01/05/2024] [Indexed: 01/27/2024]
Abstract
At a great many locations worldwide, the safety of drinking water is not assured due to pollution with arsenic. Arsenic toxicity is a matter of both systems chemistry and systems biology: it is determined by complex and intertwined networks of chemical reactions in the inanimate environment, in microbes in that environment, and in the human body. We here review what is known about these networks and their interconnections. We then discuss how consideration of the systems aspects of arsenic levels in groundwater may open up new avenues towards the realization of safer drinking water. Along such avenues, both geochemical and microbiological conditions can optimize groundwater microbial ecology vis-à-vis reduced arsenic toxicity.
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Affiliation(s)
- Zahid Hassan
- Department of Molecular Cell Biology, A-Life, Faculty of Science, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands;
- Department of Genetic Engineering and Biotechnology, Jagannath University, Dhaka 1100, Bangladesh
| | - Hans V. Westerhoff
- Department of Molecular Cell Biology, A-Life, Faculty of Science, Vrije Universiteit Amsterdam, 1081 HV Amsterdam, The Netherlands;
- School of Biological Sciences, Faculty of Biology, Medicine and Health, The University of Manchester, Manchester M13 9PT, UK
- Synthetic Systems Biology and Nuclear Organization, Swammerdam Institute for Life Sciences, University of Amsterdam, 1098 XH Amsterdam, The Netherlands
- Stellenbosch Institute of Advanced Studies (STIAS), Wallenberg Research Centre at Stellenbosch University, Stellenbosch 7600, South Africa
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Liao K, Liu J, Gu YL, Wang C, Wei HL. Pseudomonas cucumis sp. nov., isolated from the rhizosphere of crop plants. Int J Syst Evol Microbiol 2023; 73. [PMID: 38117210 DOI: 10.1099/ijsem.0.006208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2023] Open
Abstract
Two bacterial strains, FP1935T and FP1962, were isolated from the rhizosphere soil of cucumber and Chieh-qua plants, respectively, in Jilin Province, PR China. These strains were Gram-stain-negative, aerobic, rod-shaped and motile with one or two polar flagella. Analysis of the 16S rRNA gene sequences revealed that they represented members of the genus Pseudomonas, with the highest similarity to Pseudomonas silesiensis A3T (99.45 %), Pseudomonas frederiksbergensis JAJ28T (99.45 %), Pseudomonas mandelii NBRC 103147T (99.38 %), Pseudomonas piscium P50T (99.27 %) and Pseudomonas meliae CFBP 3225T (99.18 %). The DNA G+C contents of FP1935T and FP1962 were 58.99 mol% and 58.98 mol%, respectively. The results of in silico genome-based analyses indicated that these strains were distinct from other species in the genus Pseudomonas, as the average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values were below the recommended thresholds of 95 % (ANI) and 70 % (dDDH) for prokaryotic species delineation, with no values exceeding 94.1 and 55.8 %, respectively, compared with any other related species. The results of phenotypic and chemotaxonomic tests confirmed their differentiation from their closest relatives. The fatty acid profiles of both strains mainly consisted of summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c), summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c), C12 : 0 and C16 : 0. The predominant respiratory quinone was Q-9. Polar lipids include phosphatidylethanolamine, unidentified aminophospholipids, unidentified lipids and an unidentified phospholipid. On the basis of these phenotypic and genotypic results, we propose the name Pseudomonas cucumis sp. nov. for these novel strains. The type strain is FP1935T (=ACCC 62445T=JCM 35690T).
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Affiliation(s)
- Kaiji Liao
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Key Laboratory of Microbial Resources Collection and Preservation, Ministry of Agriculture and Rural Affairs, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
- College of Life Science and Technology of Huazhong Agricultural University, Wuhan 430070, PR China
| | - Jianying Liu
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Key Laboratory of Microbial Resources Collection and Preservation, Ministry of Agriculture and Rural Affairs, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Yi-Lin Gu
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Key Laboratory of Microbial Resources Collection and Preservation, Ministry of Agriculture and Rural Affairs, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Can Wang
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Key Laboratory of Microbial Resources Collection and Preservation, Ministry of Agriculture and Rural Affairs, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
| | - Hai-Lei Wei
- State Key Laboratory of Efficient Utilization of Arid and Semi-arid Arable Land in Northern China, Key Laboratory of Microbial Resources Collection and Preservation, Ministry of Agriculture and Rural Affairs, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, PR China
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Qing C, Nicol A, Li P, Planer-Friedrich B, Yuan C, Kou Z. Different sulfide to arsenic ratios driving arsenic speciation and microbial community interactions in two alkaline hot springs. ENVIRONMENTAL RESEARCH 2023; 218:115033. [PMID: 36502897 DOI: 10.1016/j.envres.2022.115033] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 11/21/2022] [Accepted: 12/07/2022] [Indexed: 06/17/2023]
Abstract
Arsenic (As) is ubiquitous in geothermal fluids, which threatens both water supply safety and local ecology. The co-occurrence of sulfur (S) and As increases the complexity of As migration and transformation in hot springs. Microorganisms play important roles in As-S transformation processes. In the present study, two Tibetan alkaline hot springs (designated Gulu [GL] and Daba [DB]) with different total As concentrations (0.88 mg/L and 12.42 mg/L, respectively) and different sulfide/As ratios (3.97 and 0.008, respectively) were selected for investigating interactions between As-S geochemistry and microbial communities along the outflow channels. The results showed that As-S transformation processes were similar, although concentrations and percentages of As and S species differed between the two hot springs. Thioarsenates were detected at the vents of the hot springs (18% and 0.32%, respectively), and were desulfurized to arsenite along the drainage channel. Arsenite was finally oxidized to arsenate (532 μg/L and 12,700 μg/L, respectively). Monothioarsenate, total As, and sulfate were the key factors shaping the changes in microbial communities with geochemical gradients. The relative abundances of sulfur reduction genes (dsrAB) and arsenate reduction genes (arsC) were higher in upstream portions of GL explaining high thiolation. Arsenite oxidation genes (aoxAB) were relatively abundant in downstream parts of GL and at the vent of DB explaining low thiolation. Sulfur oxidation genes (soxABXYZ) were abundant in GL and DB. Putative sulfate-reducing bacteria (SRB), such as Desulfuromusa and Clostridium, might be involved in forming thioarsenates by producing reduced S for chemical reactions with arsenite. Sulfur-oxidizing bacteria (SOB), such as Elioraea, Pseudoxanthomonas and Pseudomonas, and arsenite-oxidizing bacteria (AsOB) such as Thermus, Sulfurihydrogenibium and Hydrogenophaga, may be responsible for the oxidation of As-bound S, thereby desulfurizing thioarsenates, forming arsenite and, by further abiotic or microbial oxidation, arsenate. This study improves our understanding of As and S biogeochemistry in hot springs.
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Affiliation(s)
- Chun Qing
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430074, Wuhan, Hubei, PR China; Hubei Key Laboratory of Yangtze Catchment Environmental Aquatic Science, China University of Geosciences, 430074, Wuhan, Hubei, PR China.
| | - Alan Nicol
- Environmental Geochemistry Group, Bayreuth Center for Ecology and Environmental Research (BAYCEER), Bayreuth University, 95440, Bayreuth, Germany.
| | - Ping Li
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430074, Wuhan, Hubei, PR China; Hubei Key Laboratory of Yangtze Catchment Environmental Aquatic Science, China University of Geosciences, 430074, Wuhan, Hubei, PR China.
| | - Britta Planer-Friedrich
- Environmental Geochemistry Group, Bayreuth Center for Ecology and Environmental Research (BAYCEER), Bayreuth University, 95440, Bayreuth, Germany.
| | - Changguo Yuan
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430074, Wuhan, Hubei, PR China; Hubei Key Laboratory of Yangtze Catchment Environmental Aquatic Science, China University of Geosciences, 430074, Wuhan, Hubei, PR China.
| | - Zhu Kou
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, 430074, Wuhan, Hubei, PR China; Hubei Key Laboratory of Yangtze Catchment Environmental Aquatic Science, China University of Geosciences, 430074, Wuhan, Hubei, PR China.
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Selmani Z, Attard E, Lauga B, Barakat M, Ortet P, Tulumello J, Achouak W, Kaci Y, Heulin T. Culturing the desert microbiota. Front Microbiol 2023; 14:1098150. [PMID: 37113232 PMCID: PMC10126307 DOI: 10.3389/fmicb.2023.1098150] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Accepted: 03/27/2023] [Indexed: 04/29/2023] Open
Abstract
Over the last 30 years, the description of microbial diversity has been mainly based on culture-independent approaches (metabarcoding and metagenomics) allowing an in-depth analysis of microbial diversity that no other approach allows. Bearing in mind that culture-dependent approaches cannot replace culture-independent approaches, we have improved an original method for isolating strains consisting of "culturing" grains of sand directly on Petri dishes (grain-by-grain method). This method allowed to cultivate up to 10% of the bacteria counted on the surface of grains of the three sites studied in the Great Western Erg in Algeria (Timoudi, Béni Abbès, and Taghit), knowing that on average about 10 bacterial cells colonize each grain. The diversity of culturable bacteria (collection of 290 strains) predicted by 16S rRNA gene sequencing revealed that Arthrobacter subterraneus, Arthrobacter tecti, Pseudarthrobacter phenanthrenivorans, Pseudarthrobacter psychrotolerans, and Massilia agri are the dominant species. The comparison of the culture-dependent and -independent (16S rRNA gene metabarcoding) approaches at the Timoudi site revealed 18 bacterial genera common to both approaches with a relative overestimation of the genera Arthrobacter/Pseudarthrobacter and Kocuria, and a relative underestimation of the genera Blastococcus and Domibacillus by the bacterial culturing approach. The bacterial isolates will allow further study on the mechanisms of tolerance to desiccation, especially in Pseudomonadota (Proteobacteria).
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Affiliation(s)
- Zakia Selmani
- Laboratoire de Biologie et Physiologie des Organismes, Faculté des Sciences Biologiques, University of Science and Technology Houari Boumediene (USTHB), Algiers, Algeria
- CEA, CNRS, BIAM, LEMiRE, Aix-Marseille Université, Saint-Paul-lèz-Durance, France
| | - Eleonore Attard
- E2S UPPA, CNRS, IPREM, Université de Pau et des Pays de l’Adour, Pau, France
| | - Béatrice Lauga
- E2S UPPA, CNRS, IPREM, Université de Pau et des Pays de l’Adour, Pau, France
| | - Mohamed Barakat
- CEA, CNRS, BIAM, LEMiRE, Aix-Marseille Université, Saint-Paul-lèz-Durance, France
| | - Philippe Ortet
- CEA, CNRS, BIAM, LEMiRE, Aix-Marseille Université, Saint-Paul-lèz-Durance, France
| | - Joris Tulumello
- CEA, CNRS, BIAM, LEMiRE, Aix-Marseille Université, Saint-Paul-lèz-Durance, France
| | - Wafa Achouak
- CEA, CNRS, BIAM, LEMiRE, Aix-Marseille Université, Saint-Paul-lèz-Durance, France
| | - Yahia Kaci
- Laboratoire de Biologie et Physiologie des Organismes, Faculté des Sciences Biologiques, University of Science and Technology Houari Boumediene (USTHB), Algiers, Algeria
| | - Thierry Heulin
- CEA, CNRS, BIAM, LEMiRE, Aix-Marseille Université, Saint-Paul-lèz-Durance, France
- *Correspondence: Thierry Heulin,
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Díaz M, Bach T, González Anta G, Agaras B, Wibberg D, Noguera F, Canciani W, Valverde C. Agronomic efficiency and genome mining analysis of the wheat-biostimulant rhizospheric bacterium Pseudomonas pergaminensis sp. nov. strain 1008 T. FRONTIERS IN PLANT SCIENCE 2022; 13:894985. [PMID: 35968096 PMCID: PMC9369656 DOI: 10.3389/fpls.2022.894985] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/12/2022] [Accepted: 06/29/2022] [Indexed: 06/15/2023]
Abstract
Pseudomonas sp. strain 1008 was isolated from the rhizosphere of field grown wheat plants at the tillering stage in an agricultural plot near Pergamino city, Argentina. Based on its in vitro phosphate solubilizing capacity and the production of IAA, strain 1008 was formulated as an inoculant for bacterization of wheat seeds and subjected to multiple field assays within the period 2010-2017. Pseudomonas sp. strain 1008 showed a robust positive impact on the grain yield (+8% on average) across a number of campaigns, soil properties, seed genotypes, and with no significant influence of the simultaneous seed treatment with a fungicide, strongly supporting the use of this biostimulant bacterium as an agricultural input for promoting the yield of wheat. Full genome sequencing revealed that strain 1008 has the capacity to access a number of sources of inorganic and organic phosphorus, to compete for iron scavenging, to produce auxin, 2,3-butanediol and acetoin, and to metabolize GABA. Additionally, the genome of strain 1008 harbors several loci related to rhizosphere competitiveness, but it is devoid of biosynthetic gene clusters for production of typical secondary metabolites of biocontrol representatives of the Pseudomonas genus. Finally, the phylogenomic, phenotypic, and chemotaxonomic comparative analysis of strain 1008 with related taxa strongly suggests that this wheat rhizospheric biostimulant isolate is a representative of a novel species within the genus Pseudomonas, for which the name Pseudomonas pergaminensis sp. nov. (type strain 1008T = DSM 113453T = ATCC TSD-287T) is proposed.
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Affiliation(s)
- Marisa Díaz
- Rizobacter Argentina S.A., Buenos Aires, Argentina
| | - Teresa Bach
- Rizobacter Argentina S.A., Buenos Aires, Argentina
| | - Gustavo González Anta
- Escuela de Ciencias Agrarias, Exactas y Naturales, Universidad Nacional del Noroeste de la Provincia de Buenos Aires (UNNOBA), Buenos Aires, Argentina
- Departamento de Ciencias Naturales y Exactas, Universidad Nacional de San Antonio de Areco (UNSAdA), Buenos Aires, Argentina
- Indrasa Biotecnología S.A., Córdoba, Argentina
| | - Betina Agaras
- Laboratorio de Fisiología y Genética de Bacterias Beneficiosas para Plantas, Centro de Bioquímica y Microbiología del Suelo, Universidad Nacional de Quilmes-CONICET, Buenos Aires, Argentina
| | - Daniel Wibberg
- Center for Biotechnology (CeBiTec), Bielefeld University, Bielefeld, Germany
| | | | | | - Claudio Valverde
- Laboratorio de Fisiología y Genética de Bacterias Beneficiosas para Plantas, Centro de Bioquímica y Microbiología del Suelo, Universidad Nacional de Quilmes-CONICET, Buenos Aires, Argentina
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Start-Up and Performance of a Full Scale Passive System In-Cluding Biofilters for the Treatment of Fe, as and Mn in a Neutral Mine Drainage. WATER 2022. [DOI: 10.3390/w14121963] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Passive mine drainage treatment plants are the scene of many chemical and biological reactions. Here, the establishment of iron (Fe), arsenic (As), and manganese (Mn) removal was monitored immediately after the commissioning of the Lopérec (Brittany, France) passive water treatment plant, composed of aeration cascades and settling ponds followed by pozzolana biofilters. Iron and As were almost completely removed immediately after commissioning, while Mn removal took more than 28 days to reach its maximum performance. Investigations were performed during two periods presenting strong variations in feeding flow-rates: from 2.8 m3.h−1 to 8.6 m3.h−1 and from 13.2 m3.h−1 to 31.3 m3.h−1. Design flow rate was reached during the first week of the second period. Dissolved Fe and As were not affected by the decrease in residence time while Mn was only slightly affected. Microbial communities in biofilter presented similarities with those of the pond sludge, and genera including Mn-oxidizing species were detected. Proportion of bacteria carrying the aioA gene encoding for As(III)-oxidase enzyme increased in communities during the second period. Results suggest Mn removal is mainly associated with bio-oxidation whereas removal of Fe and As could be mainly attributed to chemical oxidation and precipitation of Fe, possibly helped by As(III) bio-oxidation.
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Fernández I, de Los Ríos-Escalante P, Valenzuela A, Aguayo P, Smith CT, García-Cancino A, Sánchez-Alonso K, Oyarzún C, Campos VL. Gastrointestinal Microbiota and Parasite-Fauna of Wild Dissostichus eleginoides Smitt, 1898 Captured at the South-Central Coast of Chile. Microorganisms 2021; 9:microorganisms9122522. [PMID: 34946125 PMCID: PMC8706219 DOI: 10.3390/microorganisms9122522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Revised: 10/25/2021] [Accepted: 10/26/2021] [Indexed: 12/02/2022] Open
Abstract
Dissotichus eleginoides has a discontinuous circumpolar geographic distribution restricted to mountains and platforms, mainly in Subantarctic and Antarctic waters of the southern hemisphere, including the Southeast Pacific, Atlantic and Indian oceans and in areas surrounding the peninsular platforms of subantarctic islands. The aim of this work was to determine and characterize the gastrointestinal parasitic and microbial fauna of specimens of D. eleginoides captured in waters of the south-central zone of Chile. The magnitude of parasitism in D. eleginoides captured in waters of the south-central zone of Chile is variable, and the parasite richness is different from that reported in specimens from subantarctic environments. Next-generation sequencing (NGS) of the microbial community associated to intestine showed a high diversity, where Proteobacteria, Firmicutes, and Bacteriodetes were the dominant phyla. However, both parasitic and microbial structures can vary between fish from different geographic regions
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Affiliation(s)
- Italo Fernández
- Departamento de Microbiología, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción 4070386, Chile; (I.F.); (C.T.S.); (A.G.-C.); (K.S.-A.)
| | - Patricio de Los Ríos-Escalante
- Departamento de Ciencias Biológicas y Químicas, Facultad de Recursos Naturales, Universidad Católica de Temuco, Temuco 4780000, Chile;
- Núcleo de Estudios Ambientales, Universidad Católica de Temuco, Temuco 4780000, Chile
| | - Ariel Valenzuela
- Laboratorio de Piscicultura y Patología Acuática, Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Concepción 4070386, Chile; (A.V.); (C.O.)
| | - Paulina Aguayo
- Institute of Natural Resources, Faculty of Veterinary Medicine and Agronomy, Universidad de Las Américas, Sede Concepción, Chacabuco 539, Concepción 3349001, Chile;
- EULA Environmental Sciences Center, Faculty of Environmental Sciences, Universidad de Concepción, Concepción 4070386, Chile
| | - Carlos T. Smith
- Departamento de Microbiología, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción 4070386, Chile; (I.F.); (C.T.S.); (A.G.-C.); (K.S.-A.)
| | - Apolinaria García-Cancino
- Departamento de Microbiología, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción 4070386, Chile; (I.F.); (C.T.S.); (A.G.-C.); (K.S.-A.)
| | - Kimberly Sánchez-Alonso
- Departamento de Microbiología, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción 4070386, Chile; (I.F.); (C.T.S.); (A.G.-C.); (K.S.-A.)
| | - Ciro Oyarzún
- Laboratorio de Piscicultura y Patología Acuática, Facultad de Ciencias Naturales y Oceanográficas, Universidad de Concepción, Concepción 4070386, Chile; (A.V.); (C.O.)
| | - Víctor L. Campos
- Departamento de Microbiología, Facultad de Ciencias Biológicas, Universidad de Concepción, Casilla 160-C, Concepción 4070386, Chile; (I.F.); (C.T.S.); (A.G.-C.); (K.S.-A.)
- Correspondence:
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Vieto S, Rojas-Gätjens D, Jiménez JI, Chavarría M. The potential of Pseudomonas for bioremediation of oxyanions. ENVIRONMENTAL MICROBIOLOGY REPORTS 2021; 13:773-789. [PMID: 34369104 DOI: 10.1111/1758-2229.12999] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Accepted: 07/30/2021] [Indexed: 06/13/2023]
Abstract
Non-metal, metal and metalloid oxyanions occur naturally in minerals and rocks of the Earth's crust and are mostly found in low concentrations or confined in specific regions of the planet. However, anthropogenic activities including urban development, mining, agriculture, industrial activities and new technologies have increased the release of oxyanions to the environment, which threatens the sustainability of natural ecosystems, in turn affecting human development. For these reasons, the implementation of new methods that could allow not only the remediation of oxyanion contaminants but also the recovery of valuable elements from oxyanions of the environment is imperative. From this perspective, the use of microorganisms emerges as a strategy complementary to physical, mechanical and chemical methods. In this review, we discuss the opportunities that the Pseudomonas genus offers for the bioremediation of oxyanions, which is derived from its specialized central metabolism and the high number of oxidoreductases present in the genomes of these bacteria. Finally, we review the current knowledge on the transport and metabolism of specific oxyanions in Pseudomonas species. We consider that the Pseudomonas genus is an excellent starting point for the development of biotechnological approaches for the upcycling of oxyanions into added-value metal and metalloid byproducts.
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Affiliation(s)
- Sofía Vieto
- Centro Nacional de Innovaciones Biotecnológicas (CENIBiot), CeNAT-CONARE, San José, 1174-1200, Costa Rica
| | - Diego Rojas-Gätjens
- Centro Nacional de Innovaciones Biotecnológicas (CENIBiot), CeNAT-CONARE, San José, 1174-1200, Costa Rica
| | - José I Jiménez
- Department of Life Sciences, Imperial College London, South Kensington Campus, London, SW7 2AZ, UK
| | - Max Chavarría
- Centro Nacional de Innovaciones Biotecnológicas (CENIBiot), CeNAT-CONARE, San José, 1174-1200, Costa Rica
- Centro de Investigaciones en Productos Naturales (CIPRONA), Universidad de Costa Rica, San José, 11501-2060, Costa Rica
- Escuela de Química, Universidad de Costa Rica, San José, 11501-2060, Costa Rica
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11
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Ziegelhöfer A, Kujala K. Assessing the Diversity and Metabolic Potential of Psychrotolerant Arsenic-Metabolizing Microorganisms From a Subarctic Peatland Used for Treatment of Mining-Affected Waters by Culture-Dependent and -Independent Techniques. Front Microbiol 2021; 12:648412. [PMID: 34295311 PMCID: PMC8290898 DOI: 10.3389/fmicb.2021.648412] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2020] [Accepted: 06/08/2021] [Indexed: 12/22/2022] Open
Abstract
Arsenic contamination in water by natural causes or industrial activities is a major environmental concern, and treatment of contaminated waters is needed to protect water resources and minimize the risk for human health. In mining environments, treatment peatlands are used in the polishing phase of water treatment to remove arsenic (among other contaminants), and peat microorganisms play a crucial role in arsenic removal. The present study assessed culture-independent diversity obtained through metagenomic and metatranscriptomic sequencing and culture-dependent diversity obtained by isolating psychrotolerant arsenic-tolerant, arsenite-oxidizing, and arsenate-respiring microorganisms from a peatland treating mine effluent waters of a gold mine in Finnish Lapland using a dilution-to-extinction technique. Low diversity enrichments obtained after several transfers were dominated by the genera Pseudomonas, Polaromonas, Aeromonas, Brevundimonas, Ancylobacter, and Rhodoferax. Even though maximal growth and physiological activity (i.e., arsenite oxidation or arsenate reduction) were observed at temperatures between 20 and 28°C, most enrichments also showed substantial growth/activity at 2–5°C, indicating the successful enrichments of psychrotolerant microorganisms. After additional purification, eight arsenic-tolerant, five arsenite-oxidizing, and three arsenate-respiring strains were obtained in pure culture and identified as Pseudomonas, Rhodococcus, Microbacterium, and Cadophora. Some of the enriched and isolated genera are not known to metabolize arsenic, and valuable insights on arsenic turnover pathways may be gained by their further characterization. Comparison with phylogenetic and functional data from the metagenome indicated that the enriched and isolated strains did not belong to the most abundant genera, indicating that culture-dependent and -independent methods capture different fractions of the microbial community involved in arsenic turnover. Rare biosphere microorganisms that are present in low abundance often play an important role in ecosystem functioning, and the enriched/isolated strains might thus contribute substantially to arsenic turnover in the treatment peatland. Psychrotolerant pure cultures of arsenic-metabolizing microorganisms from peatlands are needed to close the knowledge gaps pertaining to microbial arsenic turnover in peatlands located in cold climate regions, and the isolates and enrichments obtained in this study are a good starting point to establish model systems. Improved understanding of their metabolism could moreover lead to their use in biotechnological applications intended for bioremediation of arsenic-contaminated waters.
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Affiliation(s)
- Aileen Ziegelhöfer
- Faculty for Chemistry & Biotechnology, Aachen University of Applied Sciences, Jülich, Germany.,Water, Energy and Environmental Engineering Research Unit, University of Oulu, Oulu, Finland
| | - Katharina Kujala
- Water, Energy and Environmental Engineering Research Unit, University of Oulu, Oulu, Finland
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12
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Garrido-Sanz D, Redondo-Nieto M, Martin M, Rivilla R. Comparative genomics of the Pseudomonas corrugata subgroup reveals high species diversity and allows the description of Pseudomonas ogarae sp. nov. Microb Genom 2021; 7:000593. [PMID: 34184980 PMCID: PMC8461476 DOI: 10.1099/mgen.0.000593] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Accepted: 04/26/2021] [Indexed: 12/29/2022] Open
Abstract
Pseudomonas corrugata constitute one of the phylogenomic subgroups within the Pseudomonas fluorescens species complex and include both plant growth-promoting rhizobacteria (PGPR) and plant pathogenic bacteria. Previous studies suggest that the species diversity of this group remains largely unexplored together with frequent misclassification of strains. Using more than 1800 sequenced Pseudomonas genomes we identified 121 genomes belonging to the P. corrugata subgroup. Intergenomic distances obtained using the genome-to-genome blast distance (GBDP) algorithm and the determination of digital DNA-DNA hybridization values were further used for phylogenomic and clustering analyses, which revealed 29 putative species clusters, of which only five correspond to currently named species within the subgroup. Comparative and functional genome-scale analyses also support the species status of these clusters. The search for PGPR and plant pathogenic determinants showed that approximately half of the genomes analysed could have a pathogenic behaviour based on the presence of a pathogenicity genetic island, while all analysed genomes possess PGPR traits. Finally, this information together with the characterization of phenotypic traits, allows the reclassification proposal of Pseudomonas fluorescens F113 as Pseudomonas ogarae sp. nov., nom rev., type strain F113T (=DSM 112162T=CECT 30235T), which is substantiated by genomic, functional genomics and phenotypic differences with their closest type strains.
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Affiliation(s)
- Daniel Garrido-Sanz
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Darwin 2, 28049 Madrid, Spain
- Department of Fundamental Microbiology, University of Lausanne, CH-1015 Lausanne, Switzerland
| | - Miguel Redondo-Nieto
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Darwin 2, 28049 Madrid, Spain
| | - Marta Martin
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Darwin 2, 28049 Madrid, Spain
| | - Rafael Rivilla
- Departamento de Biología, Facultad de Ciencias, Universidad Autónoma de Madrid, Darwin 2, 28049 Madrid, Spain
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13
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Herrera C, Moraga R, Bustamante B, Vilo C, Aguayo P, Valenzuela C, Smith CT, Yáñez J, Guzmán-Fierro V, Roeckel M, Campos VL. Characterization of Arsenite-Oxidizing Bacteria Isolated from Arsenic-Rich Sediments, Atacama Desert, Chile. Microorganisms 2021; 9:microorganisms9030483. [PMID: 33668956 PMCID: PMC7996500 DOI: 10.3390/microorganisms9030483] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 12/29/2020] [Accepted: 12/29/2020] [Indexed: 11/16/2022] Open
Abstract
Arsenic (As), a semimetal toxic for humans, is commonly associated with serious health problems. The most common form of massive and chronic exposure to As is through consumption of contaminated drinking water. This study aimed to isolate an As resistant bacterial strain to characterize its ability to oxidize As (III) when immobilized in an activated carbon batch bioreactor and to evaluate its potential to be used in biological treatments to remediate As contaminated waters. The diversity of bacterial communities from sediments of the As-rich Camarones River, Atacama Desert, Chile, was evaluated by Illumina sequencing. Dominant taxonomic groups (>1%) isolated were affiliated with Proteobacteria and Firmicutes. A high As-resistant bacterium was selected (Pseudomonas migulae VC-19 strain) and the presence of aio gene in it was investigated. Arsenite detoxification activity by this bacterial strain was determined by HPLC/HG/AAS. Particularly when immobilized on activated carbon, P. migulae VC-19 showed high rates of As(III) conversion (100% oxidized after 36 h of incubation). To the best of our knowledge, this is the first report of a P. migulae arsenite oxidizing strain that is promising for biotechnological application in the treatment of arsenic contaminated waters.
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Affiliation(s)
- Constanza Herrera
- Laboratory of Environmental Microbiology, Department of Microbiology, Faculty of Biological Sciences, Universidad de Concepcion, Concepcion 4070386, Chile; (C.H.); (B.B.); (C.V.); (P.A.); (C.V.); (C.T.S.)
| | - Ruben Moraga
- Microbiology Laboratory, Faculty of Renewable Natural Resources, Arturo Prat University, Iquique 1100000, Chile
- Correspondence: (R.M.); (V.L.C.)
| | - Brian Bustamante
- Laboratory of Environmental Microbiology, Department of Microbiology, Faculty of Biological Sciences, Universidad de Concepcion, Concepcion 4070386, Chile; (C.H.); (B.B.); (C.V.); (P.A.); (C.V.); (C.T.S.)
| | - Claudia Vilo
- Laboratory of Environmental Microbiology, Department of Microbiology, Faculty of Biological Sciences, Universidad de Concepcion, Concepcion 4070386, Chile; (C.H.); (B.B.); (C.V.); (P.A.); (C.V.); (C.T.S.)
| | - Paulina Aguayo
- Laboratory of Environmental Microbiology, Department of Microbiology, Faculty of Biological Sciences, Universidad de Concepcion, Concepcion 4070386, Chile; (C.H.); (B.B.); (C.V.); (P.A.); (C.V.); (C.T.S.)
- Faculty of Environmental Sciences, EULA-Chile, Universidad de Concepcion, Concepcion 4070386, Chile
- Institute of Natural Resources, Faculty of Veterinary Medicine and Agronomy, Universidad de Las Américas, Sede Concepcion, Campus El Boldal, Av. Alessandri N°1160, Concepcion 4090940, Chile
| | - Cristian Valenzuela
- Laboratory of Environmental Microbiology, Department of Microbiology, Faculty of Biological Sciences, Universidad de Concepcion, Concepcion 4070386, Chile; (C.H.); (B.B.); (C.V.); (P.A.); (C.V.); (C.T.S.)
| | - Carlos T. Smith
- Laboratory of Environmental Microbiology, Department of Microbiology, Faculty of Biological Sciences, Universidad de Concepcion, Concepcion 4070386, Chile; (C.H.); (B.B.); (C.V.); (P.A.); (C.V.); (C.T.S.)
| | - Jorge Yáñez
- Faculty of Chemical Sciences, Department of Analytical and Inorganic Chemistry, University of Concepción, Concepción 4070386, Chile;
| | - Victor Guzmán-Fierro
- Department of Chemical Engineering, Faculty of Engineering, University of Concepción, Concepcion 4070386, Chile; (V.G.-F.); (M.R.)
| | - Marlene Roeckel
- Department of Chemical Engineering, Faculty of Engineering, University of Concepción, Concepcion 4070386, Chile; (V.G.-F.); (M.R.)
| | - Víctor L. Campos
- Laboratory of Environmental Microbiology, Department of Microbiology, Faculty of Biological Sciences, Universidad de Concepcion, Concepcion 4070386, Chile; (C.H.); (B.B.); (C.V.); (P.A.); (C.V.); (C.T.S.)
- Correspondence: (R.M.); (V.L.C.)
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14
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Characterization of the Bacterial Biofilm Communities Present in Reverse-Osmosis Water Systems for Haemodialysis. Microorganisms 2020; 8:microorganisms8091418. [PMID: 32942620 PMCID: PMC7564833 DOI: 10.3390/microorganisms8091418] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 08/14/2020] [Accepted: 08/19/2020] [Indexed: 02/03/2023] Open
Abstract
Biofilm in reverse osmosis (RO) membranes is a common problem in water treatment at haemodialysis facilities. Bacteria adhere and proliferate on RO membranes, forming biofilms, obstructing and damaging the membranes and allowing the transfer of bacteria and/or cellular components potentially harmful to the health of haemodialysis patients. Our aim was to characterize the bacterial community associated to biofilm of RO membranes and to identify potentially pathogenic bacteria present in the haemodialysis systems of two dialysis centres in Chile. The diversity of the bacterial communities present on RO membranes and potable and osmosed water samples was evaluated using Illumina sequencing. Additionally, bacteria from potable water, osmosed water and RO membrane samples were isolated, characterized and identified by Sanger’s sequencing. The molecular analyses of metagenomics showed that the phyla having a greater relative abundance in both dialysis centres were Proteobacteria and Planctomycetes. Pseudomonas, Stenotrophomonas, Agrobacterium, Pigmentiphaga, Ralstonia, Arthrobacter, Bacteroides and Staphylococcus were bacterial genera isolated from the different samples obtained at both haemodialysis centres. Pseudomonas spp. was a bacterial genus with greater frequency in all samples. Pseudomonas and Staphylococcus showed higher levels of resistance to the antibiotics tested. Results demonstrated the presence of potentially pathogenic bacteria, showing resistance to antimicrobials on RO membranes and in osmosed water in both dialysis centres studied.
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15
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Pavlov MS, Lira F, Martinez JL, Olivares-Pacheco J, Marshall SH. Pseudomonas fildesensis sp. nov., a psychrotolerant bacterium isolated from Antarctic soil of King George Island, South Shetland Islands. Int J Syst Evol Microbiol 2020; 70:3255-3263. [PMID: 32375985 DOI: 10.1099/ijsem.0.004165] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The strain KG01T was isolated from a soil sample from King George Island, Antarctica. Cells of KG01T are rod-shaped and motile by means of multiple polar flagella. The absence of arginine dihydrolase activity could be a key feature to readily distinguish KG01T from its closest phylogenetic relative species. The main fatty acids of the strain include summed feature 3 (C16 : 1 ω7c and/or C15 : 0 iso 2-OH), C16 : 0 and C18 : 1 ω7c. Phylogenetic analysis based on the 16S rRNA gene sequence and on a multilocus sequence analysis (MLSA) using housekeeping genes (16S rRNA, rpoB, rpoD, gyrB) were carried out. These analyses allowed us to include the strain within the Pseudomonas fluorescens group, presenting the highest similarity of multilocus sequence with Pseudomonas veronii LMG 17761T (96.67 %). The genome of KG01T was sequenced and in silico compared with genomes of the most closely related species of the P. fluorescens group. The average nucleotide identity (ANIb) and average amino acid identity (AAI) values of the species phylogenetically closest to KG01T were less than 95-96 %, threshold currently accepted to define strain as belonging to a bacterial species, the highest scores being those to Pseudomonas veronii LMG 17761T (87.98 %) and Pseudomonas marginalis ICMP 3553T (91.90 %). Therefore, the phenotypic and genotypic analyses results, allow us to propose that KG01T represents a member of a novel species of the genus Pseudomonas, for which the name Pseudomonas fildesensis is proposed, and KG01T (=CECT 9084T;=DSM 102036T) is established as the type strain .
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Affiliation(s)
- Maria S Pavlov
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Avenida Universidad 330, Valparaíso, Chile
| | - Felipe Lira
- IRHS, Agrocampus-Ouest, INRA, Université d'Angers, SFR 4207 QuaSaV, 49071, Beaucouzé, France
| | - José Luis Martinez
- Centro Nacional de Biotecnología, CNB, CSIC, Darwin 3, Campus de Cantoblanco, Madrid, Spain
| | - Jorge Olivares-Pacheco
- Millennium Initiative for Collaborative Research on Bacterial Resistance (MICROB-R). Santiago, Chile.,Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Avenida Universidad 330, Valparaíso, Chile
| | - Sergio H Marshall
- Laboratorio de Genética e Inmunología Molecular, Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Avenida Universidad 330, Valparaíso, Chile
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16
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Lescure T, Joulian C, Charles C, Ben Ali Saanda T, Charron M, Breeze D, Bauda P, Battaglia-Brunet F. Simple or complex organic substrates inhibit arsenite oxidation and aioA gene expression in two β-Proteobacteria strains. Res Microbiol 2020; 171:13-20. [DOI: 10.1016/j.resmic.2019.09.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 09/04/2019] [Accepted: 09/06/2019] [Indexed: 11/30/2022]
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17
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Han YH, Yin DX, Jia MR, Wang SS, Chen Y, Rathinasabapathi B, Chen DL, Ma LQ. Arsenic-resistance mechanisms in bacterium Leclercia adecarboxylata strain As3-1: Biochemical and genomic analyses. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 690:1178-1189. [PMID: 31470481 DOI: 10.1016/j.scitotenv.2019.07.098] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 07/06/2019] [Accepted: 07/07/2019] [Indexed: 06/10/2023]
Abstract
Microbial arsenic transformation is important in As biogeochemical cycles in the environment. In this study, a new As-resistant bacterial strain Leclercia adecarboxylata As3-1 was isolated and its associated mechanisms in As resistance and detoxification were evaluated based on genome sequencing and gene annotations. After subjecting strain As3-1 to medium containing arsenate (AsV), AsV reduction occurred and an AsV-enhanced bacterial growth was observed. Strain As3-1 lacked arsenite (AsIII) oxidation ability and displayed lower AsIII resistance than AsV, probably due to its higher AsIII accumulation. Polymerase chain reaction and phylogenetic analysis showed that strain As3-1 harbored a typical AsV reductase gene (arsC) on the plasmids. Genome sequencing and gene annotations identified four operons phoUpstBACS, arsHRBC, arsCRDABC and ttrRSBCA, with 8 additional genes outside the operons that might have involved in As resistance and detoxification in strain As3-1. These included 5 arsC genes explaining why strain As3-1 tolerated high AsV concentrations. Besides ArsC, TtrB, TtrC and TtrA proteins could also be involved in AsV reduction and consequent energy acquisition for bacterial growth. Our data provided a new example of diverse As-regulating systems and AsV-enhanced growth without ArrA in bacteria. The information helps to understand the role of As in selecting microbial systems that can transform and utilize As.
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Affiliation(s)
- Yong-He Han
- Quangang Petrochemical Research Institute, Fujian Normal University, Quanzhou, Fujian 362801, China; College of Environmental Science and Engineering, Fujian Normal University, Fuzhou, Fujian 350007, China; Fujian Key Laboratory of Pollution Control and Resource Reuse, Fuzhou 350007, China
| | - Dai-Xia Yin
- School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Meng-Ru Jia
- School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Shan-Shan Wang
- Quangang Petrochemical Research Institute, Fujian Normal University, Quanzhou, Fujian 362801, China
| | - Yanshan Chen
- School of the Environment, Nanjing Normal University, Nanjing, Jiangsu 210023, China
| | - Bala Rathinasabapathi
- Horticultural Sciences Department, University of Florida, Gainesville, FL 32611, United States
| | - Deng-Long Chen
- Quangang Petrochemical Research Institute, Fujian Normal University, Quanzhou, Fujian 362801, China; Innovative Center for Eco-Friendly Polymeric Materials, Quanzhou, Fujian 362801, China.
| | - Lena Q Ma
- College of Environmental Science and Engineering, Fujian Normal University, Fuzhou, Fujian 350007, China; Soil and Water Sciences Department, University of Florida, Gainesville, FL 32611, United States.
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18
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Lindsay MR, Amenabar MJ, Fecteau KM, Debes RV, Fernandes Martins MC, Fristad KE, Xu H, Hoehler TM, Shock EL, Boyd ES. Subsurface processes influence oxidant availability and chemoautotrophic hydrogen metabolism in Yellowstone hot springs. GEOBIOLOGY 2018; 16:674-692. [PMID: 30035368 DOI: 10.1111/gbi.12308] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2018] [Revised: 04/15/2018] [Accepted: 06/20/2018] [Indexed: 06/08/2023]
Abstract
The geochemistry of hot springs and the availability of oxidants capable of supporting microbial metabolisms are influenced by subsurface processes including the separation of hydrothermal fluids into vapor and liquid phases. Here, we characterized the influence of geochemical variation and oxidant availability on the abundance, composition, and activity of hydrogen (H2 )-dependent chemoautotrophs along the outflow channels of two-paired hot springs in Yellowstone National Park. The hydrothermal fluid at Roadside East (RSE; 82.4°C, pH 3.0) is acidic due to vapor-phase input while the fluid at Roadside West (RSW; 68.1°C, pH 7.0) is circumneutral due to liquid-phase input. Most chemotrophic communities exhibited net rates of H2 oxidation, consistent with H2 support of primary productivity, with one chemotrophic community exhibiting a net rate of H2 production. Abundant H2 -oxidizing chemoautotrophs were supported by reduction in oxygen, elemental sulfur, sulfate, and nitrate in RSW and oxygen and ferric iron in RSE; O2 utilizing hydrogenotrophs increased in abundance down both outflow channels. Sequencing of 16S rRNA transcripts or genes from native sediments and dilution series incubations, respectively, suggests that members of the archaeal orders Sulfolobales, Desulfurococcales, and Thermoproteales are likely responsible for H2 oxidation in RSE, whereas members of the bacterial order Thermoflexales and the archaeal order Thermoproteales are likely responsible for H2 oxidation in RSW. These observations suggest that subsurface processes strongly influence spring chemistry and oxidant availability, which in turn select for unique assemblages of H2 oxidizing microorganisms. Therefore, these data point to the role of oxidant availability in shaping the ecology and evolution of hydrogenotrophic organisms.
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Affiliation(s)
- Melody R Lindsay
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana
| | | | - Kristopher M Fecteau
- School of Molecular Sciences, Arizona State University, Tempe, Arizona
- School of Earth and Space Exploration, Arizona State University, Tempe, Arizona
| | - Randal V Debes
- School of Earth and Space Exploration, Arizona State University, Tempe, Arizona
| | | | | | - Huifang Xu
- Department of Geosciences, University of Wisconsin, Madison, Wisconsin
- NASA Astrobiology Institute, Mountain View, California
| | - Tori M Hoehler
- NASA Ames Research Center, Moffett Field, California
- NASA Astrobiology Institute, Mountain View, California
| | - Everett L Shock
- School of Molecular Sciences, Arizona State University, Tempe, Arizona
- School of Earth and Space Exploration, Arizona State University, Tempe, Arizona
- NASA Astrobiology Institute, Mountain View, California
| | - Eric S Boyd
- Department of Microbiology and Immunology, Montana State University, Bozeman, Montana
- NASA Astrobiology Institute, Mountain View, California
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19
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Orellana R, Macaya C, Bravo G, Dorochesi F, Cumsille A, Valencia R, Rojas C, Seeger M. Living at the Frontiers of Life: Extremophiles in Chile and Their Potential for Bioremediation. Front Microbiol 2018; 9:2309. [PMID: 30425685 PMCID: PMC6218600 DOI: 10.3389/fmicb.2018.02309] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2018] [Accepted: 09/10/2018] [Indexed: 11/19/2022] Open
Abstract
Extremophiles are organisms capable of adjust, survive or thrive in hostile habitats that were previously thought to be adverse or lethal for life. Chile gathers a wide range of extreme environments: salars, geothermal springs, and geysers located at Altiplano and Atacama Desert, salars and cold mountains in Central Chile, and ice fields, cold lakes and fjords, and geothermal sites in Patagonia and Antarctica. The aims of this review are to describe extremophiles that inhabit main extreme biotopes in Chile, and their molecular and physiological capabilities that may be advantageous for bioremediation processes. After briefly describing the main ecological niches of extremophiles along Chilean territory, this review is focused on the microbial diversity and composition of these biotopes microbiomes. Extremophiles have been isolated in diverse zones in Chile that possess extreme conditions such as Altiplano, Atacama Desert, Central Chile, Patagonia, and Antarctica. Interesting extremophiles from Chile with potential biotechnological applications include thermophiles (e.g., Methanofollis tationis from Tatio Geyser), acidophiles (e.g., Acidithiobacillus ferrooxidans, Leptospirillum ferriphilum from Atacama Desert and Central Chile copper ores), halophiles (e.g., Shewanella sp. Asc-3 from Altiplano, Streptomyces sp. HKF-8 from Patagonia), alkaliphiles (Exiguobacterium sp. SH31 from Altiplano), xerotolerant bacteria (S. atacamensis from Atacama Desert), UV- and Gamma-resistant bacteria (Deinococcus peraridilitoris from Atacama Desert) and psychrophiles (e.g., Pseudomonas putida ATH-43 from Antarctica). The molecular and physiological properties of diverse extremophiles from Chile and their application in bioremediation or waste treatments are further discussed. Interestingly, the remarkable adaptative capabilities of extremophiles convert them into an attractive source of catalysts for bioremediation and industrial processes.
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Affiliation(s)
- Roberto Orellana
- Laboratorio de Microbiología Molecular y Biotecnología Ambiental, Departamento de Química and Centro de Biotecnología Daniel Alkalay Lowitt, Universidad Técnica Federico Santa María, Valparaíso, Chile
- Departamento de Biología, Facultad de Ciencias Naturales y Exactas, Universidad de Playa Ancha, Valparaíso, Chile
| | - Constanza Macaya
- Laboratorio de Microbiología Molecular y Biotecnología Ambiental, Departamento de Química and Centro de Biotecnología Daniel Alkalay Lowitt, Universidad Técnica Federico Santa María, Valparaíso, Chile
| | - Guillermo Bravo
- Laboratorio de Microbiología Molecular y Biotecnología Ambiental, Departamento de Química and Centro de Biotecnología Daniel Alkalay Lowitt, Universidad Técnica Federico Santa María, Valparaíso, Chile
| | - Flavia Dorochesi
- Laboratorio de Microbiología Molecular y Biotecnología Ambiental, Departamento de Química and Centro de Biotecnología Daniel Alkalay Lowitt, Universidad Técnica Federico Santa María, Valparaíso, Chile
| | - Andrés Cumsille
- Laboratorio de Microbiología Molecular y Biotecnología Ambiental, Departamento de Química and Centro de Biotecnología Daniel Alkalay Lowitt, Universidad Técnica Federico Santa María, Valparaíso, Chile
| | - Ricardo Valencia
- Laboratorio de Microbiología Molecular y Biotecnología Ambiental, Departamento de Química and Centro de Biotecnología Daniel Alkalay Lowitt, Universidad Técnica Federico Santa María, Valparaíso, Chile
| | - Claudia Rojas
- Laboratorio de Microbiología Molecular y Biotecnología Ambiental, Departamento de Química and Centro de Biotecnología Daniel Alkalay Lowitt, Universidad Técnica Federico Santa María, Valparaíso, Chile
| | - Michael Seeger
- Laboratorio de Microbiología Molecular y Biotecnología Ambiental, Departamento de Química and Centro de Biotecnología Daniel Alkalay Lowitt, Universidad Técnica Federico Santa María, Valparaíso, Chile
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20
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Tapase SR, Kodam KM. Assessment of arsenic oxidation potential of Microvirga indica S-MI1b sp. nov. in heavy metal polluted environment. CHEMOSPHERE 2018; 195:1-10. [PMID: 29241075 DOI: 10.1016/j.chemosphere.2017.12.022] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 12/01/2017] [Accepted: 12/05/2017] [Indexed: 06/07/2023]
Abstract
Arsenic oxidizing α-proteobacterial strain Microvirga indica S-MI1b sp. nov. was isolated from metal industry soil and has the ability to oxidize 15 mM of arsenite [As(III)] completely in 39 h. The strain S-MI1b resists to different heavy metals and it oxidizes arsenite in presence of Li, Pb, Hg, Sb(III), Cd, Cr(VI), Ni, and exhibited growth inhibitory effect in presence of Hg, Cu, and Cd at higher concentration. The morphology of Microvirga indica S-MI1b changed in presence of heavy metals however there was no accumulation of As(III) in the cells. The study showed that Microvirga indica S-MI1b can oxidize arsenite at broad pH ranges from 4.0 to 9.0 with optimum at pH 7.0. The kinetic studies of arsenite oxidation by strain S-MI1b signified that it has greater affinity towards As(III). The arsenite oxidase activity of cells grown in presence of Li and Cr(VI) supported the cell culture studies. This is first report on biotransformation of arsenite by Microvirga genus and also arsenite oxidation in presence of heavy metals.
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Affiliation(s)
- Savita R Tapase
- Biochemistry Division, Department of Chemistry, Savitribai Phule Pune University, Pune, 411007, India
| | - Kisan M Kodam
- Biochemistry Division, Department of Chemistry, Savitribai Phule Pune University, Pune, 411007, India.
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21
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Razmilic V, Castro JF, Marchant F, Asenjo JA, Andrews B. Metabolic modelling and flux analysis of microorganisms from the Atacama Desert used in biotechnological processes. Antonie van Leeuwenhoek 2018; 111:1479-1491. [DOI: 10.1007/s10482-018-1031-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Accepted: 01/25/2018] [Indexed: 01/16/2023]
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22
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Kaminski MA, Furmanczyk EM, Sobczak A, Dziembowski A, Lipinski L. Pseudomonas silesiensis sp. nov. strain A3 T isolated from a biological pesticide sewage treatment plant and analysis of the complete genome sequence. Syst Appl Microbiol 2018; 41:13-22. [DOI: 10.1016/j.syapm.2017.09.002] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 08/30/2017] [Accepted: 09/01/2017] [Indexed: 11/15/2022]
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The current status on the taxonomy of Pseudomonas revisited: An update. INFECTION GENETICS AND EVOLUTION 2017; 57:106-116. [PMID: 29104095 DOI: 10.1016/j.meegid.2017.10.026] [Citation(s) in RCA: 131] [Impact Index Per Article: 18.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2017] [Revised: 10/28/2017] [Accepted: 10/30/2017] [Indexed: 12/20/2022]
Abstract
The genus Pseudomonas described in 1894 is one of the most diverse and ubiquitous bacterial genera which encompass species isolated worldwide. In the last years more than 70 new species have been described, which were isolated from different environments, including soil, water, sediments, air, animals, plants, fungi, algae, compost, human and animal related sources. Some of these species have been isolated in extreme environments, such as Antarctica or Atacama desert, and from contaminated water or soil. Also, some species recently described are plant or animal pathogens. In this review, we revised the current status of the taxonomy of genus Pseudomonas and the methodologies currently used for the description of novel species which includes, in addition to the classic ones, new methodologies such as MALDI-TOF MS, MLSA and genome analyses. The novel Pseudomonas species described in the last years are listed, together with the available genome sequences of the type strains of Pseudomonas species present in different databases.
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24
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Liu Y, Zhang Z, Li Y, Wen Y, Fei Y. Response of soil microbial communities to roxarsone pollution along a concentration gradient. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2017; 52:819-827. [PMID: 28276888 DOI: 10.1080/10934529.2017.1281687] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
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 degradation.
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Affiliation(s)
- Yaci Liu
- a Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences , Shijiazhuang , China
- b Key Laboratory of Groundwater Remediation of Hebei Province and China Geological Survey , Shijiazhuang, Hebei , China
| | - Zhaoji Zhang
- a Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences , Shijiazhuang , China
| | - Yasong Li
- a Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences , Shijiazhuang , China
- c CSIRO Land and Water , Urrbrae , South Australia , Australia
| | - Yi Wen
- d Department of Water Environmental Planning , Chinese Academy for Environmental Planning , Beijing , China
| | - Yuhong Fei
- a Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences , Shijiazhuang , China
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25
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Bull AT, Asenjo JA, Goodfellow M, Gómez-Silva B. The Atacama Desert: Technical Resources and the Growing Importance of Novel Microbial Diversity. Annu Rev Microbiol 2017; 70:215-34. [PMID: 27607552 DOI: 10.1146/annurev-micro-102215-095236] [Citation(s) in RCA: 75] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The Atacama Desert of northern Chile is the oldest and most arid nonpolar environment on Earth. It is a coastal desert covering approximately 180,000 km(2), and together with the greater Atacama region it comprises a dramatically wide range of ecological niches. Long known and exploited for its mineral resources, the Atacama Desert harbors a rich microbial diversity that has only recently been discovered; the great majority of it has not yet been recovered in culture or even taxonomically identified. This review traces the progress of microbiology research in the Atacama and dispels the popular view that this region is virtually devoid of life. We examine reasons for such research activity and demonstrate that microbial life is the latest recognized and least explored resource in this inspiring biome.
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Affiliation(s)
- Alan T Bull
- School of Biosciences, University of Kent, Canterbury CT2 7NJ, United Kingdom;
| | - Juan A Asenjo
- Center for Biotechnology and Bioengineering, University of Chile, Santiago, Chile.,Department of Chemical Engineering and Biotechnology, University of Chile, Santiago, Chile;
| | - Michael Goodfellow
- School of Biology, Newcastle University, Newcastle upon Tyne NE1 7RU, United Kingdom;
| | - Benito Gómez-Silva
- Biochemistry Laboratory, Biomedical Department, Faculty of Health Sciences, University of Antofagasta, Chile;
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26
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Liu Y, Zhang Z, Li Y, Fei Y. Response of microbial communities to roxarsone under different culture conditions. Can J Microbiol 2017; 63:661-670. [PMID: 28177786 DOI: 10.1139/cjm-2016-0652] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Roxarsone is a feed additive widely used in the broiler and swine industries that has the potential to contaminate the environment, mainly via the use of poultry manure as fertilizer, which results in release of inorganic arsenic to the soil and water. This study was conducted to investigate roxarsone degradation and the response of the microbial community under different culture conditions using high-throughput sequencing technology. Poultry litter was incubated for 288 h in the presence of roxarsone under light aerobic, dark aerobic, or dark anaerobic conditions. The results showed that roxarsone was completely degraded after 48 h of dark anaerobic incubation, while 79.9% and 94.5% of roxarsone was degraded after 288 h of dark aerobic and light aerobic incubation, respectively. Under dark aerobic conditions with microbial inhibitor sodium azide, roxarsone was rarely degraded during the 288 h of incubation, illustrating that microorganisms play an important role in roxarsone degradation. Microbial community structure was significantly different among various culture conditions. Olivibacter, Sphingobacterium, and Proteiniphilum were the top 3 genera in the control samples. Sphingobacterium and Alishewanella dominated the light aerobic samples, while the dominant microflora of the dark aerobic samples were Acinetobacter spp. Pseudomonas and Advenella were the predominant genera of dark anaerobic samples. This study emphasizes the potential importance of microbes in roxarsone degradation and expands our current understanding of microbial ecology during roxarsone degradation under different environmental conditions.
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Affiliation(s)
- Yaci Liu
- a Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences, Shijiazhuang, Hebei 050061, People's Republic of China.,b Key Laboratory of Groundwater Remediation of Hebei Province and China Geological Survey, Shijiazhuang, Hebei 050061, People's Republic of China
| | - Zhaoji Zhang
- a Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences, Shijiazhuang, Hebei 050061, People's Republic of China
| | - Yasong Li
- a Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences, Shijiazhuang, Hebei 050061, People's Republic of China.,b Key Laboratory of Groundwater Remediation of Hebei Province and China Geological Survey, Shijiazhuang, Hebei 050061, People's Republic of China.,c CSIRO Land and Water, Urrbrae, South Australia 5064, Australia
| | - Yuhong Fei
- a Institute of Hydrogeology and Environmental Geology, Chinese Academy of Geological Sciences, Shijiazhuang, Hebei 050061, People's Republic of China
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27
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Zhang Z, Yin N, Cai X, Wang Z, Cui Y. Arsenic redox transformation by Pseudomonas sp. HN-2 isolated from arsenic-contaminated soil in Hunan, China. J Environ Sci (China) 2016; 47:165-173. [PMID: 27593283 DOI: 10.1016/j.jes.2015.11.036] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Revised: 10/12/2015] [Accepted: 11/04/2015] [Indexed: 06/06/2023]
Abstract
A mesophilic, Gram-negative, arsenite[As(III)]-oxidizing and arsenate[As(V)]-reducing bacterial strain, Pseudomonas sp. HN-2, was isolated from an As-contaminated soil. Phylogenetic analysis based on 16S rRNA gene sequencing indicated that the strain was closely related to Pseudomonas stutzeri. Under aerobic conditions, this strain oxidized 92.0% (61.4μmol/L) of arsenite to arsenate within 3hr of incubation. Reduction of As(V) to As(III) occurred in anoxic conditions. Pseudomonas sp. HN-2 is among the first soil bacteria shown to be capable of both aerobic As(III) oxidation and anoxic As(V) reduction. The strain, as an efficient As(III) oxidizer and As(V) reducer in Pseudomonas, has the potential to impact arsenic mobility in both anoxic and aerobic environments, and has potential application in As remediation processes.
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Affiliation(s)
- Zhennan Zhang
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, China; Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
| | - Naiyi Yin
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, China; Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Xiaolin Cai
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, China; Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Zhenzhou Wang
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, China; Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Yanshan Cui
- College of Resources and Environment, University of Chinese Academy of Sciences, Beijing 101408, China; Research Center for Eco-environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
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28
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Lin JY, Hobson WJ, Wertz JT. Ventosimonas gracilis gen. nov., sp. nov., a member of the Gammaproteobacteria isolated from Cephalotes varians ant guts representing a new family, Ventosimonadaceae fam. nov., within the order 'Pseudomonadales'. Int J Syst Evol Microbiol 2016; 66:2869-2875. [PMID: 27054961 DOI: 10.1099/ijsem.0.001068] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Cephalotes 'turtle' ants are known to harbor a core group of gut symbionts, including members belonging to the Gammaproteobacteria. Here, we describe the cultivation and characterization of strain CV58T, a novel member of the Gammaproteobacteria order Pseudomonadales isolated from the guts of the ant Cephalotes varians. Strain CV58T was rod-shaped, Gram-stain-negative, non-motile and formed pale-yellow colonies on trypticase soy agar. Optimum growth occurred under an atmosphere of 4-20 % (v/v) O2. Growth was possible for strain CV58Tat NaCl concentrations of 0-1.5 % (w/v), temperatures of 23-40 °C, and pH values of 5.5-8.5. The G+C content of the genomic DNA was 54.9 mol% and the major fatty acids were C18 : 1ω7c, C16 : 0, C16 : 1ω7c/C16 : 1ω6c, C12 : 0 and C12 : 03OH. The only respiratory quinone detected was ubiquinone-9 (Q-9) and the major polar lipids were phosphatidylethanolamine, phosphatidylglycerol and diphosphatidylglycerol. Based on phylogenetic analysis of the 16S rRNA gene sequence, strain CV58T shared an 88.3 % nucleotide identity with its closest cultivated neighbor, Pseudomonas putida R43. We believe that this, combined with the housekeeping gene phylogeny, differences in phenotypic characteristics and cellular fatty acid compositions of other cultivated members indicates that strain CV58T represents a novel species occupying a novel genus and family within the order Pseudomonadales. Thus, we propose the name Ventosimonadaceae fam nov., followed by Ventosimonas gracilis gen. nov., sp. nov., to classify strain CV58T (=NCIMB 15011T =DSM 100910T).
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Affiliation(s)
- Jonathan Y Lin
- Department of Biology, Calvin College, Grand Rapids, MI, USA
| | | | - John T Wertz
- Department of Biology, Calvin College, Grand Rapids, MI, USA
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29
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Valenzuela C, Moraga R, Leon C, Smith CT, Mondaca MA, Campos VL. Arsenite oxidation by Pseudomonas arsenicoxydans immobilized on zeolite and its potential biotechnological application. BULLETIN OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY 2015; 94:667-673. [PMID: 25673523 DOI: 10.1007/s00128-015-1495-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2014] [Accepted: 02/04/2015] [Indexed: 06/04/2023]
Abstract
Pseudomonas arsenicoxydans has been recently described as a new arsenite oxidizing bacterial species. Arsenite detoxification activity by this species was determined by HPLC/HG/AAS. P. arsenicoxydans showed a high rate of As(III) conversion, particularly when immobilized (it oxidizes 100 % of 500 μg arsenite present in the medium after 48 of incubation). Arsenite oxidizing activity, mediated by a constitutive periplasmic enzyme, was determined following the transfer of reducing equivalents from arsenite to 2,4-dichlorophenolindophenol (DCIP) showing that approximately 75 % (0.173 µmol DCIP min(-1) mg(-1)) of the total activity (0.231 µmol DCIP min(-1) mg(-1)) was detected in the periplasmic fraction. Using PCR with primers specific for arsenite oxidase gene showed the presence of a gene encoding for arsenite oxidase in P. arsenicoxydans. Results show the potential biotechnological application of P. arsenicoxydans as a candidate for detoxification of As(III).
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Affiliation(s)
- Cristian Valenzuela
- Environmental Microbiology Laboratory, Department of Microbiology, Faculty of Biological Sciences, University of Concepcion, P.O. Box 160-C, Correo 3, Concepción, Chile
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30
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Koechler S, Arsène-Ploetze F, Brochier-Armanet C, Goulhen-Chollet F, Heinrich-Salmeron A, Jost B, Lièvremont D, Philipps M, Plewniak F, Bertin PN, Lett MC. Constitutive arsenite oxidase expression detected in arsenic-hypertolerant Pseudomonas xanthomarina S11. Res Microbiol 2015; 166:205-14. [PMID: 25753102 DOI: 10.1016/j.resmic.2015.02.010] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2014] [Revised: 02/05/2015] [Accepted: 02/20/2015] [Indexed: 02/06/2023]
Abstract
Pseudomonas xanthomarina S11 is an arsenite-oxidizing bacterium isolated from an arsenic-contaminated former gold mine in Salsigne, France. This bacterium showed high resistance to arsenite and was able to oxidize arsenite to arsenate at concentrations up to 42.72 mM As[III]. The genome of this strain was sequenced and revealed the presence of three ars clusters. One of them is located on a plasmid and is organized as an "arsenic island" harbouring an aio operon and genes involved in phosphorous metabolism, in addition to the ars genes. Neither the aioXRS genes nor a specific sigma-54-dependent promoter located upstream of aioBA genes, both involved in regulation of arsenite oxidase expression in other arsenite-oxidizing bacteria, could be identified in the genome. This observation is in accordance with the fact that no difference was observed in expression of arsenite oxidase in P. xanthomarina S11, whether or not the strain was grown in the presence of As[III].
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Affiliation(s)
- Sandrine Koechler
- UMR7156 Université de Strasbourg/CNRS Génétique Moléculaire, Génomique, Microbiologie, Département Micro-organismes, Génomes, Environnement, 28 rue Goethe, 67083 Strasbourg Cedex, France.
| | - Florence Arsène-Ploetze
- UMR7156 Université de Strasbourg/CNRS Génétique Moléculaire, Génomique, Microbiologie, Département Micro-organismes, Génomes, Environnement, 28 rue Goethe, 67083 Strasbourg Cedex, France.
| | - Céline Brochier-Armanet
- Université de Lyon, Université Lyon 1, CNRS, UMR5558, Laboratoire de Biométrie et Biologie Evolutive, 43 boulevard du 11 Novembre 1918, F-69622 Villeurbanne, France.
| | - Florence Goulhen-Chollet
- UMR7156 Université de Strasbourg/CNRS Génétique Moléculaire, Génomique, Microbiologie, Département Micro-organismes, Génomes, Environnement, 28 rue Goethe, 67083 Strasbourg Cedex, France.
| | - Audrey Heinrich-Salmeron
- UMR7156 Université de Strasbourg/CNRS Génétique Moléculaire, Génomique, Microbiologie, Département Micro-organismes, Génomes, Environnement, 28 rue Goethe, 67083 Strasbourg Cedex, France.
| | - Bernard Jost
- Plateforme Biopuces et séquençage, IGBMC, 1 rue Laurent Fries Parc d'Innovation, 67400 Illkirch, France.
| | - Didier Lièvremont
- UMR7156 Université de Strasbourg/CNRS Génétique Moléculaire, Génomique, Microbiologie, Département Micro-organismes, Génomes, Environnement, 28 rue Goethe, 67083 Strasbourg Cedex, France.
| | - Muriel Philipps
- Plateforme Biopuces et séquençage, IGBMC, 1 rue Laurent Fries Parc d'Innovation, 67400 Illkirch, France.
| | - Frédéric Plewniak
- UMR7156 Université de Strasbourg/CNRS Génétique Moléculaire, Génomique, Microbiologie, Département Micro-organismes, Génomes, Environnement, 28 rue Goethe, 67083 Strasbourg Cedex, France.
| | - Philippe N Bertin
- UMR7156 Université de Strasbourg/CNRS Génétique Moléculaire, Génomique, Microbiologie, Département Micro-organismes, Génomes, Environnement, 28 rue Goethe, 67083 Strasbourg Cedex, France.
| | - Marie-Claire Lett
- UMR7156 Université de Strasbourg/CNRS Génétique Moléculaire, Génomique, Microbiologie, Département Micro-organismes, Génomes, Environnement, 28 rue Goethe, 67083 Strasbourg Cedex, France.
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Arnau VG, Sánchez LA, Delgado OD. Pseudomonas yamanorum sp. nov., a psychrotolerant bacterium isolated from a subantarctic environment. Int J Syst Evol Microbiol 2015; 65:424-431. [DOI: 10.1099/ijs.0.065201-0] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A psychrotolerant strain, 8H1T, was isolated from soil samples collected in Isla de los Estados, Ushuaia, Argentina. Cells were Gram-negative, aerobic, straight rods, occurring singly or in pairs, non-spore-forming and motile by means of two polar flagella. The isolate was able to grow in the range 4–35 °C, with optimum growth at 28 °C. The predominant cellular fatty acids were summed feature 3 (C16 : 1ω6c and/or C16 : 1ω7c), C16 : 0 and summed feature 8 (C18 : 1ω6c and/or C18 : 1ω7c). The polar lipid pattern of strain 8H1T comprised phosphatidylglycerol, diphosphatidylglycerol, phosphatidylethanolamine and an unknown phospholipid. Ubiquinone 9 (Q-9) was the predominant lipoquinone. The DNA G+C content was 59.8 mol%. 16S rRNA gene sequence-based phylogeny suggested the affiliation of strain 8H1T to the ‘Pseudomonas fluorescens group’, displaying ≥98.5 % sequence similarity to 29 type strains. A multilocus sequence analysis (MLSA) study performed by concatenating 16S rRNA, gyrB, rpoD and rpoB gene sequences showed that isolate 8H1T could be discriminated from closely related species of the genus
Pseudomonas
and placed in the ‘Pseudomonas gessardii subgroup’, including the species with the highest MLSA sequence similarities:
Pseudomonas brenneri
(96.2 %),
P. gessardii
(96.1 %),
P. proteolytica
(96.0 %),
P. meridiana
(96.0 %) and
P. mucidolens
(95.4 %). DNA–DNA hybridization analysis between 8H1T and the type strains of these closely related species revealed relatedness values of 27.0, 8.8, 41.2, 39.7 and 46.1 %, respectively. These results, together with differences in several phenotypic features, support the classification of a novel species, for which the name Pseudomonas yamanorum sp. nov. is proposed. The type strain is 8H1T ( = DSM 26522T = CCUG 63249T = LMG 27247T).
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Affiliation(s)
| | | | - Osvaldo Daniel Delgado
- Centro de Investigación y Transferencia Catamarca (CITCa), Universidad Nacional de Catamarca, CONICET, Av. Belgrano 300 (K4700AAP), San Fernando del Valle de Catamarca, Catamarca, Argentina
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Biotechnological applications derived from microorganisms of the Atacama Desert. BIOMED RESEARCH INTERNATIONAL 2014; 2014:909312. [PMID: 25147824 PMCID: PMC4132489 DOI: 10.1155/2014/909312] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/07/2014] [Revised: 06/29/2014] [Accepted: 07/07/2014] [Indexed: 01/18/2023]
Abstract
The Atacama Desert in Chile is well known for being the driest and oldest desert on Earth. For these same reasons, it is also considered a good analog model of the planet Mars. Only a few decades ago, it was thought that this was a sterile place, but in the past years fascinating adaptations have been reported in the members of the three domains of life: low water availability, high UV radiation, high salinity, and other environmental stresses. However, the biotechnological applications derived from the basic understanding and characterization of these species, with the notable exception of copper bioleaching, are still in its infancy, thus offering an immense potential for future development.
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Cébron A, Arsène-Ploetze F, Bauda P, Bertin PN, Billard P, Carapito C, Devin S, Goulhen-Chollet F, Poirel J, Leyval C. Rapid impact of phenanthrene and arsenic on bacterial community structure and activities in sand batches. MICROBIAL ECOLOGY 2014; 67:129-44. [PMID: 24189653 DOI: 10.1007/s00248-013-0313-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Accepted: 10/10/2013] [Indexed: 05/08/2023]
Abstract
The impact of both organic and inorganic pollution on the structure of soil microbial communities is poorly documented. A short-time batch experiment (6 days) was conducted to study the impact of both types of pollutants on the taxonomic, metabolic and functional diversity of soil bacteria. For this purpose sand spiked with phenanthrene (500 mg kg(-1) sand) or arsenic (arsenite 0.66 mM and arsenate 12.5 mM) was supplemented with artificial root exudates and was inoculated with bacteria originated from an aged PAH and heavy-metal-polluted soil. The bacterial community was characterised using bacterial strain isolation, TTGE fingerprinting and proteomics. Without pollutant, or with phenanthrene or arsenic, there were no significant differences in the abundance of bacteria and the communities were dominated by Pseudomonas and Paenibacillus genera. However, at the concentrations used, both phenanthrene or arsenic were toxic as shown by the decrease in mineralisation activities. Using community-level physiological profiles (Biolog Ecoplates™) or differential proteomics, we observed that the pollutants had an impact on the community physiology, in particular phenanthrene induced a general cellular stress response with changes in the central metabolism and membrane protein synthesis. Real-time PCR quantification of functional genes and transcripts revealed that arsenic induced the transcription of functional arsenic resistance and speciation genes (arsB, ACR3 and aioA), while no transcription of PAH-degradation genes (PAH-dioxygenase and catechol-dioxygenase) was detected with phenanthrene. Altogether, in our tested conditions, pollutants do not have a major effect on community abundance or taxonomic composition but rather have an impact on metabolic and functional bacterial properties.
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Affiliation(s)
- A Cébron
- LIEC UMR7360, CNRS-Université de Lorraine, Faculté des Sciences et Technologies, BP 70239, 54506, Vandoeuvre-lès-Nancy Cedex, France,
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Bahar MM, Megharaj M, Naidu R. Kinetics of arsenite oxidation by Variovorax sp. MM-1 isolated from a soil and identification of arsenite oxidase gene. JOURNAL OF HAZARDOUS MATERIALS 2013; 262:997-1003. [PMID: 23290483 DOI: 10.1016/j.jhazmat.2012.11.064] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/14/2012] [Revised: 11/29/2012] [Accepted: 11/30/2012] [Indexed: 06/01/2023]
Abstract
A Gram-negative, arsenite-oxidizing bacterial strain, MM-1 tolerant to 20mM arsenite and 200 mM arsenate was isolated from a heavy metal contaminated soil which contained only 8.8 mg kg(-1) of arsenic. Based on 16S rRNA analysis, the strain was closely related to the genus Variovorax. This strain completely oxidized 500 μM of arsenite to arsenate within 3h of incubation in minimal salts medium. Kinetic studies of arsenite oxidation by the cells showed one of the lowest Km (17 μM) and highest Vmax (1.23 × 10(-7) μM min(-1) cell(-1)) values reported to date for whole cell suspension. PCR analysis using degenerate primers confirmed the presence of arsenite oxidase gene and its amino acid sequence was 70-91% identical to the large subunit of most reported arsenite oxidases. The significant arsenite oxidation capacity shown by the strain opens the way to its potential application in arsenic remediation process.
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Affiliation(s)
- Md Mezbaul Bahar
- Centre for Environmental Risk Assessment and Remediation (CERAR), University of South Australia, Mawson Lakes Boulevard, Mawson Lakes, SA 5095, Australia; Cooperative Research Centre for Contamination Assessment and Remediation of the Environment (CRC CARE), Mawson Lakes Bvd., Mawson lakes, SA 5095, Australia
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Pseudomonas prosekii sp. nov., a Novel Psychrotrophic Bacterium from Antarctica. Curr Microbiol 2013; 67:637-46. [DOI: 10.1007/s00284-013-0406-6] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Accepted: 05/07/2013] [Indexed: 11/25/2022]
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Mulet M, Gomila M, Scotta C, Sánchez D, Lalucat J, García-Valdés E. Concordance between whole-cell matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry and multilocus sequence analysis approaches in species discrimination within the genus Pseudomonas. Syst Appl Microbiol 2013; 35:455-64. [PMID: 23140936 DOI: 10.1016/j.syapm.2012.08.007] [Citation(s) in RCA: 80] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2012] [Revised: 07/31/2012] [Accepted: 08/10/2012] [Indexed: 10/27/2022]
Abstract
Multilocus sequence analysis (MLSA) is one of the most accepted methods for the phylogenetic assignation of Pseudomonas strains to their corresponding species. Furthermore, updated databases are essential for correct bacterial identification and the number of Pseudomonas species is increasing continuously. Currently, 127 species are validly described in Euzéby's List of Species with Standing in Nomenclature, and 29 novel species have been described since the publication of the last comprehensive MLSA phylogenetic study based on the sequences of the 16S rDNA, gyrB, rpoB and rpoD genes. Therefore, an update of the sequence database is presented, together with the analysis of the phylogeny of the genus Pseudomonas. Whole-cell matrix-assisted laser-desorption/ionization time-of-flight (WC-MALDI-TOF) mass spectrometry (MS) analysis has been applied very recently to the identification of bacteria and is considered to be a fast and reliable method. A total of 133 type strains of the recognized species and subspecies in the genus Pseudomonas, together with other representative strains, were analyzed using this new technique, and the congruence between the WC-MALDI-TOF MS and MLSA techniques was assessed for the discrimination and correct species identification of the strains. The utility of both methods in the identification of environmental and clinical strains is discussed.
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Affiliation(s)
- Magdalena Mulet
- Microbiología, Departamento de Biología, Universidad de las Islas Baleares, 07122 Palma de Mallorca, Islas Baleares, Spain
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Bachate SP, Khapare RM, Kodam KM. Oxidation of arsenite by two β-proteobacteria isolated from soil. Appl Microbiol Biotechnol 2011; 93:2135-45. [PMID: 21983709 DOI: 10.1007/s00253-011-3606-7] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Revised: 08/29/2011] [Accepted: 09/22/2011] [Indexed: 10/17/2022]
Abstract
Two heterotrophic As(III)-oxidizing bacteria, SPB-24 and SPB-31 were isolated from garden soil. Based on 16S rRNA gene sequence analysis, strain SPB-24 was closely related to genus Bordetella, and strain SPB-31 was most closely related to genus Achromobacter. Both strains exhibited high As(III) (15 mM for SPB-24 and 40 mM for SPB-31) and As(V) (>300 mM for both strains) resistance. Both strains oxidized 5 mM As(III) in minimal medium with oxidation rate of 554 and 558 μM h(-1) for SPB-24 and SPB-31, respectively. Washed cells of both strains oxidized As(III) over broad pH and temperature range with optimum pH 6 and temperature 42°C for both strains. The As(III) oxidation kinetic by washed cells showed K (m) and V (max) values of 41.7 μM and 1,166 μM h(-1) for SPB-24, 52 μM and 1,186 μM h(-1) for SPB-31. In the presence of minimal amount of carbon source, the strains showed high As(III) oxidation rate and high specific arsenite oxidase activity. The ability of strains to resist high concentration of arsenic and oxidize As(III) with highest rates reported so far makes them potential candidates for bioremediation of arsenic-contaminated environment.
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Affiliation(s)
- Sachin P Bachate
- Division of Biochemistry, Department of Chemistry, University of Pune, Pune, 411007, India
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List of new names and new combinations previously effectively, but not validly, published. Int J Syst Evol Microbiol 2011. [DOI: 10.1099/ijs.0.030445-0] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The purpose of this announcement is to effect the valid publication of the following effectively published new names and new combinations under the procedure described in the Bacteriological Code (1990 Revision). Authors and other individuals wishing to have new names and/or combinations included in future lists should send three copies of the pertinent reprint or photocopies thereof, or an electronic copy of the published paper, to the IJSEM Editorial Office for confirmation that all of the other requirements for valid publication have been met. It is also a requirement of IJSEM and the ICSP that authors of new species, new subspecies and new combinations provide evidence that types are deposited in two recognized culture collections in two different countries. It should be noted that the date of valid publication of these new names and combinations is the date of publication of this list, not the date of the original publication of the names and combinations. The authors of the new names and combinations are as given below, and these authors' names will be included in the author index of the present issue. Inclusion of a name on these lists validates the publication of the name and thereby makes it available in bacteriological nomenclature. The inclusion of a name on this list is not to be construed as taxonomic acceptance of the taxon to which the name is applied. Indeed, some of these names may, in time, be shown to be synonyms, or the organisms may be transferred to another genus, thus necessitating the creation of a new combination.
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