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Won S, Shin C, Kang HY. Potential Self-Attenuation of Arsenic by Indigenous Microorganisms in the Nakdong River. Microorganisms 2023; 11:1910. [PMID: 37630470 PMCID: PMC10457984 DOI: 10.3390/microorganisms11081910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Revised: 07/17/2023] [Accepted: 07/25/2023] [Indexed: 08/27/2023] Open
Abstract
The toxic element arsenic (As) has become the major focus of global research owing to its harmful effects on human health, resulting in the establishment of several guidelines to prevent As contamination. The widespread industrial use of As has led to its accumulation in the environment, increasing the necessity to develop effective remediation technologies. Among various treatments, such as chemical, physical, and biological treatments, used to remediate As-contaminated environments, biological methods are the most economical and eco-friendly. Microbial oxidation of arsenite (As(III)) to arsenate (As(V)) is a primary detoxification strategy for As remediation as it reduces As toxicity and alters its mobility in the environment. Here, we evaluated the self-detoxification potential of microcosms isolated from Nakdong River water by investigating the autotrophic and heterotrophic oxidation of As(III) to As(V). Experimental data revealed that As(III) was oxidized to As(V) during the autotrophic and heterotrophic growth of river water microcosms. However, the rate of oxidation was significantly higher under heterotrophic conditions because of the higher cell growth and density in an organic-matter-rich environment compared to that under autotrophic conditions without the addition of external organic matter. At an As(III) concentration > 5 mM, autotrophic As(III) oxidation remained incomplete, even after an extended incubation time. This inhibition can be attributed to the toxic effect of the high contaminant concentration on bacterial growth and the acidification of the growth medium with the oxidation of As(III) to As(V). Furthermore, we isolated representative pure cultures from both heterotrophic- and autotrophic-enriched cultures. The new isolates revealed new members of As(III)-oxidizing bacteria in the diversified bacterial community. This study highlights the natural process of As attenuation within river systems, showing that microcosms in river water can detoxify As under both organic-matter-rich and -deficient conditions. Additionally, we isolated the bacterial strains HTAs10 and ATAs5 from the microcosm which can be further investigated for potential use in As remediation systems. Our findings provide insights into the microbial ecology of As(III) oxidation in river ecosystems and provide a foundation for further investigations into the application of these bacteria for bioremediation.
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Affiliation(s)
- Sangmin Won
- Department of Microbiology, Pusan National University, Busan 46241, Republic of Korea
- Education/Research Group of Longevity and Marine Biotechnology for Innovative Talent, Pusan National University, Busan 46241, Republic of Korea
| | - Chajeong Shin
- BUSAN IL Science Highschool, Busan 49317, Republic of Korea;
| | - Ho Young Kang
- Department of Microbiology, Pusan National University, Busan 46241, Republic of Korea
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Thouin H, Battaglia-Brunet F, Norini MP, Le Forestier L, Charron M, Dupraz S, Gautret P. Influence of environmental changes on the biogeochemistry of arsenic in a soil polluted by the destruction of chemical weapons: A mesocosm study. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 627:216-226. [PMID: 29426144 DOI: 10.1016/j.scitotenv.2018.01.158] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Revised: 01/16/2018] [Accepted: 01/16/2018] [Indexed: 06/08/2023]
Abstract
Thermal destruction of chemical munitions from World War I led to the formation of a heavily contaminated residue that contains an unexpected mineral association in which a microbial As transformation has been observed. A mesocosm study was conducted to assess the impact of water saturation episodes and input of bioavailable organic matter (OM) on pollutant behavior in relation to biogeochemical parameters. Over a period of about eight (8) months, the contaminated soil was subjected to cycles of dry and wet periods corresponding to water table level variations. After the first four (4) months, fragmented litter from the nearby forest was placed on top of the soil. The mesocosm solid phase was sampled by three rounds of coring: at the beginning of the experiment, after four (4) months (before the addition of OM), and at the end of the experiment. Scanning electron microscopy coupled to energy dispersive X-ray spectroscopy observations showed that an amorphous phase, which was the primary carrier of As, Zn, and Cu, was unstable under water-saturated conditions and released a portion of the contaminants in solution. Precipitation of a lead arsenate chloride mineral, mimetite, in soils within the water saturated level caused the immobilization of As and Pb. Mimetite is a durable trap because of its large stability domain; however, this precipitation was limited by a low Pb concentration inducing that high amounts of As remained in solution. The addition of forest litter modified the quantities and qualities of soil OM. Microbial As transformation was affected by the addition of OM, which increased the concentration of both As(III)-oxidizing and As(V)-reducing microorganisms. The addition of OM negatively impacted the As(III) oxidizing rate, however As(III) oxidation was still the dominant reaction in accordance with the formation of arsenate-bearing minerals.
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Affiliation(s)
- Hugues Thouin
- BRGM, 3 avenue Claude Guillemin, 45060 Orléans, France; Université d'Orléans, ISTO, UMR 7327, 45071 Orléans, France; CNRS, ISTO, UMR 7327, 45071 Orléans, France; BRGM, ISTO, UMR 7327, BP 36009, 45060 Orléans, France.
| | - Fabienne Battaglia-Brunet
- BRGM, 3 avenue Claude Guillemin, 45060 Orléans, France; Université d'Orléans, ISTO, UMR 7327, 45071 Orléans, France; CNRS, ISTO, UMR 7327, 45071 Orléans, France; BRGM, ISTO, UMR 7327, BP 36009, 45060 Orléans, France
| | - Marie-Paule Norini
- Université d'Orléans, ISTO, UMR 7327, 45071 Orléans, France; CNRS, ISTO, UMR 7327, 45071 Orléans, France; BRGM, ISTO, UMR 7327, BP 36009, 45060 Orléans, France
| | - Lydie Le Forestier
- Université d'Orléans, ISTO, UMR 7327, 45071 Orléans, France; CNRS, ISTO, UMR 7327, 45071 Orléans, France; BRGM, ISTO, UMR 7327, BP 36009, 45060 Orléans, France
| | | | | | - Pascale Gautret
- Université d'Orléans, ISTO, UMR 7327, 45071 Orléans, France; CNRS, ISTO, UMR 7327, 45071 Orléans, France; BRGM, ISTO, UMR 7327, BP 36009, 45060 Orléans, France
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Leon CG, Moraga R, Valenzuela C, Gugliandolo C, Lo Giudice A, Papale M, Vilo C, Dong Q, Smith CT, Rossello-Mora R, Yañez J, Campos VL. Effect of the natural arsenic gradient on the diversity and arsenic resistance of bacterial communities of the sediments of Camarones River (Atacama Desert, Chile). PLoS One 2018; 13:e0195080. [PMID: 29715297 PMCID: PMC5929503 DOI: 10.1371/journal.pone.0195080] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2017] [Accepted: 03/17/2018] [Indexed: 12/20/2022] Open
Abstract
Arsenic (As), a highly toxic metalloid, naturally present in Camarones River (Atacama Desert, Chile) is a great health concern for the local population and authorities. In this study, the taxonomic and functional characterization of bacterial communities associated to metal-rich sediments from three sites of the river (sites M1, M2 and M3), showing different arsenic concentrations, were evaluated using a combination of approaches. Diversity of bacterial communities was evaluated by Illumina sequencing. Strains resistant to arsenic concentrations varying from 0.5 to 100 mM arsenite or arsenate were isolated and the presence of genes coding for enzymes involved in arsenic oxidation (aio) or reduction (arsC) investigated. Bacterial communities showed a moderate diversity which increased as arsenic concentrations decreased along the river. Sequences of the dominant taxonomic groups (abundances ≥1%) present in all three sites were affiliated to Proteobacteria (range 40.3–47.2%), Firmicutes (8.4–24.8%), Acidobacteria (10.4–17.1%), Actinobacteria (5.4–8.1%), Chloroflexi (3.9–7.5%), Planctomycetes (1.2–5.3%), Gemmatimonadetes (1.2–1.5%), and Nitrospirae (1.1–1.2%). Bacterial communities from sites M2 and M3 showed no significant differences in diversity between each other (p = 0.9753) but they were significantly more diverse than M1 (p<0.001 and p<0.001, respectively). Sequences affiliated with Proteobacteria, Firmicutes, Acidobacteria, Chloroflexi and Actinobacteria at M1 accounted for more than 89% of the total classified bacterial sequences present but these phyla were present in lesser proportions in M2 and M3 sites. Strains isolated from the sediment of sample M1, having the greatest arsenic concentration (498 mg kg-1), showed the largest percentages of arsenic oxidation and reduction. Genes aio were more frequently detected in isolates from M1 (54%), whereas arsC genes were present in almost all isolates from all three sediments, suggesting that bacterial communities play an important role in the arsenic biogeochemical cycle and detoxification of arsenical compounds. Overall, results provide further knowledge on the microbial diversity of arsenic contaminated fresh-water sediments.
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Affiliation(s)
- Carla G. Leon
- Environmental Microbiology Laboratory, Department of Microbiology, Faculty of Biological Sciences, University of Concepción, Concepción, Chile
| | - Ruben Moraga
- Microbiology Laboratory, Faculty of Renewable Natural Resources, Arturo Prat University, Iquique, Chile
| | - Cristian Valenzuela
- Environmental Microbiology Laboratory, Department of Microbiology, Faculty of Biological Sciences, University of Concepción, Concepción, Chile
| | - Concetta Gugliandolo
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Messina, Italy
| | - Angelina Lo Giudice
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Messina, Italy
- Institute for the Coastal Marine Environment, National Research Council (IAMC-CNR), Messina, Italy
| | - Maria Papale
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Messina, Italy
| | - Claudia Vilo
- Environmental Microbiology Laboratory, Department of Microbiology, Faculty of Biological Sciences, University of Concepción, Concepción, Chile
| | - Qunfeng Dong
- Center for Biomedical Informatics, Department of Public Health Sciences, Loyola University Chicago, Maywood, Illinois, United States of America
| | - Carlos T. Smith
- Environmental Microbiology Laboratory, Department of Microbiology, Faculty of Biological Sciences, University of Concepción, Concepción, Chile
| | - Ramon Rossello-Mora
- Marine Microbiology Group, Institut Mediterrani d’Estudis Avancats (CSIC-UIB), Esporles, Spain
| | - Jorge Yañez
- Department of Analytical and Inorganic Chemistry, Faculty of Chemical Sciences, University of Concepcion, Concepcion, Chile
| | - Victor L. Campos
- Environmental Microbiology Laboratory, Department of Microbiology, Faculty of Biological Sciences, University of Concepción, Concepción, Chile
- * E-mail:
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Nguyen VK, Tran HT, Park Y, Yu J, Lee T. Microbial arsenite oxidation with oxygen, nitrate, or an electrode as the sole electron acceptor. ACTA ACUST UNITED AC 2017; 44:857-868. [DOI: 10.1007/s10295-017-1910-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Accepted: 01/29/2017] [Indexed: 10/20/2022]
Abstract
Abstract
The purpose of this study was to identify bacteria that can perform As(III) oxidation for environmental bioremediation. Two bacterial strains, named JHS3 and JHW3, which can autotrophically oxidize As(III)–As(V) with oxygen as an electron acceptor, were isolated from soil and water samples collected in the vicinity of an arsenic-contaminated site. According to 16S ribosomal RNA sequence analysis, both strains belong to the ɤ-Proteobacteria class and share 99% sequence identity with previously described strains. JHS3 appears to be a new strain of the Acinetobacter genus, whereas JHW3 is likely to be a novel strain of the Klebsiella genus. Both strains possess the aioA gene encoding an arsenite oxidase and are capable of chemolithoautotrophic growth in the presence of As(III) up to 10 mM as a primary electron donor. Cell growth and As(III) oxidation rate of both strains were significantly enhanced during cultivation under heterotrophic conditions. Under anaerobic conditions, only strain JHW3 oxidized As(III) using nitrate or a solid-state electrode of a bioelectrochemical system as a terminal electron acceptor. Kinetic studies of As(III) oxidation under aerobic condition demonstrated a higher V max and K m from strain JHW3 than strain JHS3. This study indicated the potential application of strain JHW3 for remediation of subsurface environments contaminated with arsenic.
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Affiliation(s)
- Van Khanh Nguyen
- 0000 0001 2218 7142 grid.255166.3 Department of Environmental Engineering Dong-a University 49315 Busan Republic of Korea
| | - Huong T Tran
- 0000 0001 0719 8572 grid.262229.f Department of Molecular Biology Pusan National University 46241 Busan Republic of Korea
| | - Younghyun Park
- 0000 0001 0719 8572 grid.262229.f Department of Civil and Environmental Engineering Pusan National University No. 2 Busandaehak-ro 63beon-gil, Geumjeong-gu 46241 Busan Republic of Korea
| | - Jaecheul Yu
- 0000 0001 0719 8572 grid.262229.f Department of Civil and Environmental Engineering Pusan National University No. 2 Busandaehak-ro 63beon-gil, Geumjeong-gu 46241 Busan Republic of Korea
| | - Taeho Lee
- 0000 0001 0719 8572 grid.262229.f Department of Civil and Environmental Engineering Pusan National University No. 2 Busandaehak-ro 63beon-gil, Geumjeong-gu 46241 Busan Republic of Korea
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Nguyen VK, Park Y, Yu J, Lee T. Simultaneous arsenite oxidation and nitrate reduction at the electrodes of bioelectrochemical systems. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2016; 23:19978-19988. [PMID: 27438874 DOI: 10.1007/s11356-016-7225-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2016] [Accepted: 07/11/2016] [Indexed: 06/06/2023]
Abstract
Arsenic and nitrate contaminations in the soil and groundwater have urged the scientific community to explore suitable technologies for treatment of both contaminants. This study reports, for the first time, a novel application of bioelectrochemical systems for coupling As detoxification at the anode and denitrification at the cathode. A similar As(III) oxidation efficiency was achieved when anode potential was controlled by a potentiostat or a direct current (DC) power supply. However, a slightly lower nitrate reduction rate was obtained in reactors using DC power supply during simultaneous operation of nitrate reduction and As(III) oxidation. Microbial community analysis by denaturing gradient gel electrophoresis indicated the presence of some autotrophic As(III)-oxidizing bacteria, including Achromobacter spp., Ensifer spp., and Sinorhizobium spp., that can flexibly switch their original metabolism of using oxygen as sole electron acceptor to a new metabolism mode of using solid-state anode as sole electron acceptor driving for As(III) oxidation under anaerobic conditions. Although further research is required for validating their applicability, bioelectrochemical systems represent a brilliant technology for remediation of groundwater contaminated with nitrate and/or arsenite.
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Affiliation(s)
- Van Khanh Nguyen
- Department of Civil and Environmental Engineering, Pusan National University, 2 Busandaehak-ro 63, Geumjeong-gu, Busan, 46241, Republic of Korea
| | - Younghyun Park
- Department of Civil and Environmental Engineering, Pusan National University, 2 Busandaehak-ro 63, Geumjeong-gu, Busan, 46241, Republic of Korea
| | - Jaecheul Yu
- Department of Civil and Environmental Engineering, Pusan National University, 2 Busandaehak-ro 63, Geumjeong-gu, Busan, 46241, Republic of Korea
| | - Taeho Lee
- Department of Civil and Environmental Engineering, Pusan National University, 2 Busandaehak-ro 63, Geumjeong-gu, Busan, 46241, Republic of Korea.
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6
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Fazi S, Crognale S, Casentini B, Amalfitano S, Lotti F, Rossetti S. The Arsenite Oxidation Potential of Native Microbial Communities from Arsenic-Rich Freshwaters. MICROBIAL ECOLOGY 2016; 72:25-35. [PMID: 27090902 DOI: 10.1007/s00248-016-0768-y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Accepted: 04/06/2016] [Indexed: 06/05/2023]
Abstract
Microorganisms play an important role in speciation and mobility of arsenic in the environment, by mediating redox transformations of both inorganic and organic species. Since arsenite [As(III)] is more toxic than arsenate [As(V)] to the biota, the microbial driven processes of As(V) reduction and As(III) oxidation may play a prominent role in mediating the environmental impact of arsenic contamination. However, little is known about the ecology and dynamics of As(III)-oxidizing populations within native microbial communities exposed to natural high levels of As. In this study, two techniques for single cell quantification (i.e., flow cytometry, CARD-FISH) were used to analyze the structure of aquatic microbial communities across a gradient of arsenic (As) contamination in different freshwater environments (i.e., groundwaters, surface and thermal waters). Moreover, we followed the structural evolution of these communities and their capacity to oxidize arsenite, when experimentally exposed to high As(III) concentrations in experimental microcosms. Betaproteobacteria and Deltaproteobacteria were the main groups retrieved in groundwaters and surface waters, while Beta and Gammaproteobacteria dominated the bacteria community in thermal waters. At the end of microcosm incubations, the communities were able to oxidize up to 95 % of arsenite, with an increase of Alphaproteobacteria in most of the experimental conditions. Finally, heterotrophic As(III)-oxidizing strains (one Alphaproteobacteria and two Gammaproteobacteria) were isolated from As rich waters. Our findings underlined that native microbial communities from different arsenic-contaminated freshwaters can efficiently perform arsenite oxidation, thus contributing to reduce the overall As toxicity to the aquatic biota.
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Affiliation(s)
- Stefano Fazi
- Water Research Institute, National Research Council of Italy (IRSA-CNR), Via Salaria, km 29.300, Monterotondo, RM, 00015, Italy.
| | - Simona Crognale
- Water Research Institute, National Research Council of Italy (IRSA-CNR), Via Salaria, km 29.300, Monterotondo, RM, 00015, Italy
| | - Barbara Casentini
- Water Research Institute, National Research Council of Italy (IRSA-CNR), Via Salaria, km 29.300, Monterotondo, RM, 00015, Italy
| | - Stefano Amalfitano
- Water Research Institute, National Research Council of Italy (IRSA-CNR), Via Salaria, km 29.300, Monterotondo, RM, 00015, Italy
| | - Francesca Lotti
- Department of Ecological and Biological Sciences (DEB), Tuscia University, Viterbo, Italy
| | - Simona Rossetti
- Water Research Institute, National Research Council of Italy (IRSA-CNR), Via Salaria, km 29.300, Monterotondo, RM, 00015, Italy
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Lescure T, Moreau J, Charles C, Ben Ali Saanda T, Thouin H, Pillas N, Bauda P, Lamy I, Battaglia-Brunet F. Influence of organic matters on AsIII oxidation by the microflora of polluted soils. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2016; 38:911-925. [PMID: 26427654 DOI: 10.1007/s10653-015-9771-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2015] [Accepted: 09/23/2015] [Indexed: 06/05/2023]
Abstract
The global AsIII-oxidizing activity of microorganisms in eight surface soils from polluted sites was quantified with and without addition of organic substrates. The organic substances provided differed by their nature: either yeast extract, commonly used in microbiological culture media, or a synthetic mixture of defined organic matters (SMOM) presenting some common features with natural soil organic matter. Correlations were sought between soil characteristics and both the AsIII-oxidizing rate constants and their evolution in accordance with inputs of organic substrates. In the absence of added substrate, the global AsIII oxidation rate constant correlated positively with the concentration of intrinsic organic matter in the soil, suggesting that AsIII-oxidizing activity was limited by organic substrate availability in nutrient-poor soils. This limitation was, however, removed by 0.08 g/L of added organic carbon. In most conditions, the AsIII oxidation rate constant decreased as organic carbon input increased from 0.08 to 0.4 g/L. Incubations of polluted soils in aerobic conditions, amended or not with SMOM, resulted in short-term As mobilization in the presence of SMOM and active microorganisms. In contrast, microbial AsIII oxidation seemed to stabilize As when no organic substrate was added. Results suggest that microbial speciation of arsenic driven by nature and concentration of organic matter exerts a major influence on the fate of this toxic element in surface soils.
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Affiliation(s)
- T Lescure
- BRGM, 3 Avenue Claude Guillemin, 45060, Orléans, France
- ISTO, UMR 7327, BRGM, BP 36009, 45060, Orléans, France
- LIEC UMR 7360, CNRS-Université de Lorraine, Campus Bridoux, rue du Général Delestraint, 57070, Metz, France
- Agence de l'Environnement et de la Maîtrise de l'Energie, 20 Avenue du Grésillé, BP 90406, 49004, Angers Cedex 01, France
| | - J Moreau
- BRGM, 3 Avenue Claude Guillemin, 45060, Orléans, France
| | - C Charles
- BRGM, 3 Avenue Claude Guillemin, 45060, Orléans, France
| | | | - H Thouin
- BRGM, 3 Avenue Claude Guillemin, 45060, Orléans, France
- ISTO, UMR 7327, BRGM, BP 36009, 45060, Orléans, France
| | - N Pillas
- BRGM, 3 Avenue Claude Guillemin, 45060, Orléans, France
| | - P Bauda
- LIEC UMR 7360, CNRS-Université de Lorraine, Campus Bridoux, rue du Général Delestraint, 57070, Metz, France
| | - I Lamy
- INRA Centre de Versailles-Grignon, RD 10, 78026, Versailles Cedex, France
| | - F Battaglia-Brunet
- BRGM, 3 Avenue Claude Guillemin, 45060, Orléans, France.
- ISTO, UMR 7327, BRGM, BP 36009, 45060, Orléans, France.
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Dong DT, Yamamura S, Amachi S. Impact of Arsenite on the Bacterial Community Structure and Diversity in Soil. Microbes Environ 2016; 31:41-8. [PMID: 26903368 PMCID: PMC4791115 DOI: 10.1264/jsme2.me15093] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The impact of arsenite (As[III]) on the bacterial community structure and diversity in soil was determined by incubating soil slurries with 50, 500, and 5,000 μM As(III). As(III) was oxidized to arsenate (As[V]), and the microbial contribution to As(III) oxidation was 70–100%. PCR-denaturing gradient gel electrophoresis revealed that soil bacterial diversity decreased in the presence of As(III). Bacteria closely related to the family Bacillaceae were predominant in slurry spiked with 5,000 μM As(III). The population size of culturable As(III)-resistant bacteria was 37-fold higher in this slurry than in unspiked slurry (p < 0.01), indicating that high levels of As(III) stimulate the emergence of As(III)-resistant bacteria. As(III)-resistant bacteria isolated from slurry spiked with 5,000 μM As(III) were mainly affiliated with the genus Bacillus; however, no strains showed As(III)-oxidizing capacity. An As(III)-oxidizing bacterial community analysis based on As(III) oxidase gene (aioA) sequences demonstrated that diversity was the lowest in slurry spiked with 5,000 μM As(III). The deduced AioA sequences affiliated with Alphaproteobacteria accounted for 91–93% of all sequences in this slurry, among which those closely related to Bosea spp. were predominant (48–86%). These results suggest that exposure to high levels of As(III) has a significant impact on the composition and diversity of the soil bacterial community, including the As(III)-oxidizing bacterial community. Certain As(III)-oxidizing bacteria with strong As(III) resistance may be enriched under high As(III) levels, while more sensitive As(III) oxidizers are eliminated under these conditions.
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Jiang D, Li P, Jiang Z, Dai X, Zhang R, Wang Y, Guo Q, Wang Y. Chemolithoautotrophic arsenite oxidation by a thermophilic Anoxybacillus flavithermus strain TCC9-4 from a hot spring in Tengchong of Yunnan, China. Front Microbiol 2015; 6:360. [PMID: 25999920 PMCID: PMC4422093 DOI: 10.3389/fmicb.2015.00360] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2015] [Accepted: 04/09/2015] [Indexed: 11/13/2022] Open
Abstract
A new facultative chemolithoautotrophic arsenite (AsIII)-oxidizing bacterium TCC9-4 was isolated from a hot spring microbial mat in Tengchong of Yunnan, China. This strain could grow with AsIII as an energy source, CO2–HCO3- as a carbon source and oxygen as the electron acceptor in a minimal salts medium. Under chemolithoautotrophic conditions, more than 90% of 100 mg/L AsIII could be oxidized by the strain TCC9-4 in 36 h. Temperature was an important environmental factor that strongly influenced the AsIII oxidation rate and AsIII oxidase (Aio) activity; the highest Aio activity was found at the temperature of 40∘C. Addition of 0.01% yeast extract enhanced the growth significantly, but delayed the AsIII oxidation. On the basis of 16S rRNA phylogenetic sequence analysis, strain TCC9-4 was identified as Anoxybacillus flavithermus. To our best knowledge, this is the first report of arsenic (As) oxidation by A. flavithermus. The Aio gene in TCC9-4 might be quite novel relative to currently known gene sequences. The results of this study expand our current understanding of microbially mediated As oxidation in hot springs.
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Affiliation(s)
- Dawei Jiang
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences Wuhan, China
| | - Ping Li
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences Wuhan, China
| | - Zhou Jiang
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences Wuhan, China ; School of Environmental Studies, China University of Geosciences Wuhan, China
| | - Xinyue Dai
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences Wuhan, China
| | - Rui Zhang
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences Wuhan, China
| | - Yanhong Wang
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences Wuhan, China ; School of Environmental Studies, China University of Geosciences Wuhan, China
| | - Qinghai Guo
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences Wuhan, China ; School of Environmental Studies, China University of Geosciences Wuhan, China
| | - Yanxin Wang
- State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences Wuhan, China ; School of Environmental Studies, China University of Geosciences Wuhan, China
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