1
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Huo X, Zhou Z, Liu H, Wang G, Shi K. A PadR family transcriptional repressor regulates the transcription of chromate efflux transporter in Enterobacter sp. Z1. J Microbiol 2024; 62:355-365. [PMID: 38587592 DOI: 10.1007/s12275-024-00117-0] [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: 09/25/2023] [Revised: 01/10/2024] [Accepted: 01/23/2024] [Indexed: 04/09/2024]
Abstract
Chromium is a prevalent toxic heavy metal, and chromate [Cr(VI)] exhibits high mutagenicity and carcinogenicity. The presence of the Cr(VI) efflux protein ChrA has been identified in strains exhibiting resistance to Cr(VI). Nevertheless, certain strains of bacteria that are resistant to Cr(VI) lack the presence of ChrB, a known regulatory factor. Here, a PadR family transcriptional repressor, ChrN, has been identified as a regulator in the response of Enterobacter sp. Z1(CCTCC NO: M 2019147) to Cr(VI). The chrN gene is cotranscribed with the chrA gene, and the transcriptional expression of this operon is induced by Cr(VI). The binding capacity of the ChrN protein to Cr(VI) was demonstrated by both the tryptophan fluorescence assay and Ni-NTA purification assay. The interaction between ChrN and the chrAN operon promoter was validated by reporter gene assay and electrophoretic mobility shift assay. Mutation of the conserved histidine residues His14 and His50 resulted in loss of ChrN binding with the promoter of the chrAN operon. This observation implies that these residues are crucial for establishing a DNA-binding site. These findings demonstrate that ChrN functions as a transcriptional repressor, modulating the cellular response of strain Z1 to Cr(VI) exposure.
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Affiliation(s)
- Xueqi Huo
- National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Zijie Zhou
- National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Hongliang Liu
- School of Life Sciences and Medicine, Shandong University of Technology, Zibo, 255000, Shandong Province, People's Republic of China
| | - Gejiao Wang
- National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China
| | - Kaixiang Shi
- National Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070, People's Republic of China.
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2
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Cai Y, Chen X, Qi H, Bu F, Shaaban M, Peng QA. Genome analysis of Shewanella putrefaciens 4H revealing the potential mechanisms for the chromium remediation. BMC Genomics 2024; 25:136. [PMID: 38308218 PMCID: PMC10837877 DOI: 10.1186/s12864-024-10031-9] [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: 08/04/2023] [Accepted: 01/19/2024] [Indexed: 02/04/2024] Open
Abstract
Microbial remediation of heavy metal polluted environment is ecofriendly and cost effective. Therefore, in the present study, Shewanella putrefaciens stain 4H was previously isolated by our group from the activated sludge of secondary sedimentation tank in a dyeing wastewater treatment plant. The bacterium was able to reduce chromate effectively. The strains showed significant ability to reduce Cr(VI) in the pH range of 8.0 to 10.0 (optimum pH 9.0) and 25-42 ℃ (optimum 30 ℃) and were able to reduce 300 mg/L of Cr(VI) in 72 h under parthenogenetic anaerobic conditions. In this paper, the complete genome sequence was obtained by Nanopore sequencing technology and analyzed chromium metabolism-related genes by comparative genomics The genomic sequence of S. putrefaciens 4H has a length of 4,631,110 bp with a G + C content of 44.66% and contains 4015 protein-coding genes and 3223, 2414, 2343 genes were correspondingly annotated into the COG, KEGG, and GO databases. The qRT-PCR analysis showed that the expression of chrA, mtrC, and undA genes was up-regulated under Cr(VI) stress. This study explores the Chromium Metabolism-Related Genes of S. putrefaciens 4H and will help to deepen our understanding of the mechanisms of Cr(VI) tolerance and reduction in this strain, thus contributing to the better application of S. putrefaciens 4H in the field of remediation of chromium-contaminated environments.
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Affiliation(s)
- Yajun Cai
- College of Environmental Engineering, Wuhan Textile University, Wuhan, 430200, China
- Clean Production of Textile Printing and Dyeing Engineering Research Center of Ministry of Education, Wuhan, 430200, China
| | - Xu Chen
- College of Environmental Engineering, Wuhan Textile University, Wuhan, 430200, China
| | - Hanghang Qi
- College of Environmental Engineering, Wuhan Textile University, Wuhan, 430200, China
| | - Fantong Bu
- College of Environmental Engineering, Wuhan Textile University, Wuhan, 430200, China
| | - Muhammad Shaaban
- College of Agriculture, Henan University of Science and Technology, Luoyang, China
| | - Qi-An Peng
- College of Environmental Engineering, Wuhan Textile University, Wuhan, 430200, China.
- Clean Production of Textile Printing and Dyeing Engineering Research Center of Ministry of Education, Wuhan, 430200, China.
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3
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Li T, Du D, Li C, Zhao J, Guo L, Wang X, Zhao J, Xiang W. Investigation on Cr(VI)-bioreduction mechanism and reduction products by a novel Microbacterium sp. strain NEAU-W11. CHEMOSPHERE 2023; 343:140232. [PMID: 37734508 DOI: 10.1016/j.chemosphere.2023.140232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 08/12/2023] [Accepted: 09/18/2023] [Indexed: 09/23/2023]
Abstract
Cr(VI) widely exists in the environment and has highly toxic, carcinogenic and mutagenic effects on all organisms. Physical/chemical methods to remove chromium pollution are economically expensive and have disadvantages like high reagent consumption, energy requirements and so on, while bioremediation is an eco-friendly, simple and cost-effective way. In this study, a novel Cr(VI)-reducing strain, Microbacterium sp. NEAU-W11, was reported, and its reduction mechanism was investigated. Microbacterium sp. NEAU-W11 could effectively degrade Cr(VI) under the conditions of pH 7-10, 15-35 °C, and the coexistence of metal pollutants such as Pb and Ni, etc. In addition, both Fe3+ and Cu2+ could improve the reducing ability of strain NEAU-W11, and glucose and lactose as electron donors also had promoting effect. Heat treatment of resting cells confirmed that chromium removal was not biological sorption but biological reduction. The active reductase of strain NEAU-W11 to chromium(VI) mainly existed in the cell cytoplasm, which is the first report in the genus Microbacterium. Micro-characterization of strain NEAU-W11 and the reduction products identified the reduction products as Cr(III)-ligand complexes bound to extracellular polymeric substances (EPS). Collectively, this study systematically investigated the degradation mechanism of Microbacterium sp. NEAU-W11 and the distribution of degradation product Cr(III), providing a new reduction mechanism for the genus Microbacterium, providing a new perspective for a comprehensive understanding of the degradation and transport of chromium by bacteria, and providing theoretical reference for the migration of metal ions in environmental governance.
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Affiliation(s)
- Tingting Li
- Key Laboratory of Agricultural Microbiology of Heilongjiang Province, Northeast Agricultural University, No. 59 Mucai Street, Xiangfang District, Harbin, 150030, People's Republic of China
| | - Dandan Du
- Key Laboratory of Agricultural Microbiology of Heilongjiang Province, Northeast Agricultural University, No. 59 Mucai Street, Xiangfang District, Harbin, 150030, People's Republic of China
| | - Chenxu Li
- Key Laboratory of Agricultural Microbiology of Heilongjiang Province, Northeast Agricultural University, No. 59 Mucai Street, Xiangfang District, Harbin, 150030, People's Republic of China
| | - Junlei Zhao
- Key Laboratory of Agricultural Microbiology of Heilongjiang Province, Northeast Agricultural University, No. 59 Mucai Street, Xiangfang District, Harbin, 150030, People's Republic of China
| | - Lifeng Guo
- Key Laboratory of Agricultural Microbiology of Heilongjiang Province, Northeast Agricultural University, No. 59 Mucai Street, Xiangfang District, Harbin, 150030, People's Republic of China
| | - Xiangjing Wang
- Key Laboratory of Agricultural Microbiology of Heilongjiang Province, Northeast Agricultural University, No. 59 Mucai Street, Xiangfang District, Harbin, 150030, People's Republic of China
| | - Junwei Zhao
- Key Laboratory of Agricultural Microbiology of Heilongjiang Province, Northeast Agricultural University, No. 59 Mucai Street, Xiangfang District, Harbin, 150030, People's Republic of China.
| | - Wensheng Xiang
- Key Laboratory of Agricultural Microbiology of Heilongjiang Province, Northeast Agricultural University, No. 59 Mucai Street, Xiangfang District, Harbin, 150030, People's Republic of China; State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, People's Republic of China.
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4
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Li X, Zheng S, Li Y, Ding J, Qin W. Effectively facilitating the degradation of chloramphenicol by the synergism of Shewanella oneidensis MR-1 and the metal-organic framework. JOURNAL OF HAZARDOUS MATERIALS 2023; 454:131545. [PMID: 37148794 DOI: 10.1016/j.jhazmat.2023.131545] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 04/14/2023] [Accepted: 04/29/2023] [Indexed: 05/08/2023]
Abstract
Electroactive bacteria (EAB) and metal oxides are capable of synergistically removing chloramphenicol (CAP). However, the effects of redox-active metal-organic frameworks (MOFs) on CAP degradation with EAB are not yet known. This study investigated the synergism of iron-based MOFs (Fe-MIL-101) and Shewanella oneidensis MR-1 on CAP degradation. 0.5 g/L Fe-MIL-101 with more possible active sites led to a three-fold higher CAP removal rate in the synergistic system with MR-1 (initial bacterial concentration of 0.2 at OD600), and showed a superior catalytic effect than exogenously added Fe(III)/Fe(II) or magnetite. Mass spectrometry revealed that CAP was transformed into smaller molecular weight and less toxic metabolites in cultures. Transcriptomic analysis showed that Fe-MIL-101 enhanced the expression of genes related to nitro and chlorinated contaminants degradation. Additionally, genes encoding hydrogenases and c-type cytochromes associated with extracellular electron transfer were significantly upregulated, which may contribute to the simultaneous bioreduction of CAP both intracellularly and extracellularly. These results indicated that Fe-MIL-101 can be used as a catalyst to synergize with EAB to effectively facilitate CAP degradation, which might shed new light on the application in the in situ bioremediation of antibiotic-contaminated environments.
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Affiliation(s)
- Xin Li
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Shandong Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai, Shandong 264003, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Shiling Zheng
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Shandong Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai, Shandong 264003, PR China; Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong 266237, PR China.
| | - Yinhao Li
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Shandong Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai, Shandong 264003, PR China; University of Chinese Academy of Sciences, Beijing 100049, PR China
| | - Jiawang Ding
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Shandong Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai, Shandong 264003, PR China; Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong 266237, PR China; Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, Shandong 266071, PR China.
| | - Wei Qin
- CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation, Yantai Institute of Coastal Zone Research (YIC), Chinese Academy of Sciences (CAS), Shandong Key Laboratory of Coastal Environmental Processes, YICCAS, Yantai, Shandong 264003, PR China; Qingdao National Laboratory for Marine Science and Technology, Qingdao, Shandong 266237, PR China; Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, Shandong 266071, PR China
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5
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Li Y, Luo Q, Liu S, Su J, Chen J, Dong G, Wang Y. Transcriptome analysis of Shewanella xiamenensis co-incubated with internalized carbon dots in response to boosting Cr(VI)-bioreduction. Biochem Eng J 2023. [DOI: 10.1016/j.bej.2022.108775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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6
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Su YQ, Min SN, Jian XY, Guo YC, He SH, Huang CY, Zhang Z, Yuan S, Chen YE. Bioreduction mechanisms of high-concentration hexavalent chromium using sulfur salts by photosynthetic bacteria. CHEMOSPHERE 2023; 311:136861. [PMID: 36243096 DOI: 10.1016/j.chemosphere.2022.136861] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2022] [Revised: 08/06/2022] [Accepted: 10/10/2022] [Indexed: 06/16/2023]
Abstract
Eliminating "sulfur starvation" caused by competition for sulfate transporters between chromate and sulfate is crucial to enhance the content of sulfur-containing compounds and improve the tolerance and reduction capability of Cr(VI) in bacteria. In this study, the effects of sulfur salts on the Cr(VI) bioremediation and the possible mechanism were investigated in Rhodobacter sphaeroides SC01 by cell imaging, spectroscopy, and biochemical measurements. The results showed that, when the concentration of metabisulfite was 2.0 g L-1, and the initial OD600 was 0.33, the reduction rate of R. sphaeroides SC01 reached up to 91.3% for 500 mg L-1 Cr(VI) exposure at 96 h. Moreover, thiosulfate and sulfite also markedly increased the concentration of reduced Cr(VI) in R. sphaeroides SC01. Furthermore, the characterization results revealed that -OH, -CONH, -COOH, -SO3, -PO3, and -S-S- played a major role in the adsorption of Cr, and Cr(III) reduced by bacteria was bioprecipitated in the production of Cr2P3S9 and CrPS4. In addition, R. sphaeroids SC01 combined with metabisulfite significantly increased the activity of glutathione peroxidase and the content of glutathione (GSH) and total sulfhydryl while decreasing reactive oxygen species (ROS) accumulation and cell death induced by Cr(VI) toxic. Overall, the results of this research revealed a highly efficient and reliable strategy for Cr(VI) removal by photosynthetic bacteria combined with sulfur salts in high-concentration Cr(VI)-contaminated wastewater.
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Affiliation(s)
- Yan-Qiu Su
- College of Life Science, Sichuan Normal University, Chengdu, China.
| | - Shuang-Nan Min
- College of Life Science, Sichuan Normal University, Chengdu, China
| | - Xin-Yi Jian
- College of Life Science, Sichuan Normal University, Chengdu, China
| | - Yuan-Cheng Guo
- College of Life Science, Sichuan Normal University, Chengdu, China
| | - Shu-Hao He
- College of Life Science, Sichuan Normal University, Chengdu, China
| | - Chun-Yi Huang
- College of Life Science, Sichuan Normal University, Chengdu, China
| | - Zheng Zhang
- College of Life Science, Sichuan Normal University, Chengdu, China
| | - Shu Yuan
- College of Resources, Sichuan Agricultural University, Chengdu, China
| | - Yang-Er Chen
- College of Life Sciences, Sichuan Agricultural University, Ya'an, China.
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7
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Wu M, Wang Q, Wang C, Zeng Q, Li J, Wu H, Wu B, Xu H, Qiu Z. Strategy for enhancing Cr(VI)-contaminated soil remediation and safe utilization by microbial-humic acid-vermiculite-alginate immobilized biocomposite. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2022; 243:113956. [PMID: 35964397 DOI: 10.1016/j.ecoenv.2022.113956] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 07/21/2022] [Accepted: 08/03/2022] [Indexed: 06/15/2023]
Abstract
Bioreduction is an efficient approach to in-situ remediate Cr(VI)-contaminated soil, but further strengthening methods are still urgently needed. Herein, a novel immobilized biocomposite (B-HA-VE-SA) was successfully synthesized by embedding a efficient strain Bacillus sp. CRB-7 with humic acid (HA) combined vermiculite (VE) and sodium alginate (SA). The performance and enhancement mechanism of the immobilized biocomposite on remediating Cr(VI)-contaminated soil were also investigated by analyzing the whole-genome of CRB-7, Cr(VI) detoxification, soil microecological regulation, and subsequent crop growth response. Genomic annotation demonstrated that CRB-7 contains multiple genes contributed to Cr(VI) tolerance, Cr(VI) reduction and other metals resistance. Results showed that embedded CRB-7 biocomposites exhibited more effective reduction of Cr(VI) in soil compared with control and free CRB-7 treatment, especially B-HA-VE-SA achieved the highest Cr(VI) removal efficiency (96.18%) and the residual Cr proportion (49.04%) via multiple mechanisms including carrier effects, nutrient sustained-release, and electron-shuttle effect enhanced the bioremediation process. Furthermore, the synergies of CRB-7 and immobilizers (HA, VE and SA) significantly improved soil microecology (soil enzyme activities, microbial quantity and diversity), and engendered the evolution of microbial community composition and functional pathways. Consequently, pot experiments (Brassica napus L.) verified the plant-growth-promoting (12.00-18.00% and 43.82-69.00% higher in emergence rate and biomass) and Cr-accumulation-reducing effects (19.47-91.09% and 29.11-89.80% lower in root and aerial parts) of free and immobilized CRB-7. Taken together, these findings highlighted the superiority of B-HA-VE-SA in simultaneous remediation, microecological improvement and safe utilization of Cr(VI)-contaminated soil.
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Affiliation(s)
- Minghui Wu
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, Sichuan, PR China
| | - Qiqi Wang
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, Sichuan, PR China
| | - Can Wang
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, Sichuan, PR China
| | - Qilu Zeng
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, Sichuan, PR China
| | - Jianpeng Li
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, Sichuan, PR China
| | - Han Wu
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, Sichuan, PR China
| | - Bin Wu
- College of Ecology and Environment, Chengdu University of Technology, 1# Dongsanlu, Erxianqiao, Chengdu 610059, Sichuan, PR China
| | - Heng Xu
- Key Laboratory of Bio-Resource and Eco-Environment of Ministry of Education, College of Life Sciences, Sichuan University, Chengdu 610065, Sichuan, PR China.
| | - Zhongping Qiu
- School of Life Science and Engineering, Southwest Jiaotong University, Chengdu 610031, Sichuan, PR China.
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8
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Nixon SL, Bonsall E, Cockell CS. Limitations of microbial iron reduction under extreme conditions. FEMS Microbiol Rev 2022; 46:6645348. [PMID: 35849069 PMCID: PMC9629499 DOI: 10.1093/femsre/fuac033] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2021] [Revised: 06/23/2022] [Accepted: 07/15/2022] [Indexed: 01/09/2023] Open
Abstract
Microbial iron reduction is a widespread and ancient metabolism on Earth, and may plausibly support microbial life on Mars and beyond. Yet, the extreme limits of this metabolism are yet to be defined. To investigate this, we surveyed the recorded limits to microbial iron reduction in a wide range of characterized iron-reducing microorganisms (n = 141), with a focus on pH and temperature. We then calculated Gibbs free energy of common microbially mediated iron reduction reactions across the pH-temperature habitability space to identify thermodynamic limits. Comparing predicted and observed limits, we show that microbial iron reduction is generally reported at extremes of pH or temperature alone, but not when these extremes are combined (with the exception of a small number of acidophilic hyperthermophiles). These patterns leave thermodynamically favourable combinations of pH and temperature apparently unoccupied. The empty spaces could be explained by experimental bias, but they could also be explained by energetic and biochemical limits to iron reduction at combined extremes. Our data allow for a review of our current understanding of the limits to microbial iron reduction at extremes and provide a basis to test more general hypotheses about the extent to which biochemistry establishes the limits to life.
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Affiliation(s)
- Sophie L Nixon
- Corresponding author: Department of Earth and Environmental Sciences, Manchester Institute of Biotechnology, The University of Manchester, 131 Princess Street, Manchester, M1 7DN, UK. E-mail:
| | - Emily Bonsall
- Biological and Environmental Sciences, University of Stirling, Stirling, FK9 4LA, United Kingdom
| | - Charles S Cockell
- UK Centre for Astrobiology, School of Physics and Astronomy, University of Edinburgh, Edinburgh, EH9 3FD, United Kingdom
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9
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Biotransformation of Chromium (VI) via a Reductant Activity from the Fungal Strain Purpureocillium lilacinum. J Fungi (Basel) 2021; 7:jof7121022. [PMID: 34947004 PMCID: PMC8707924 DOI: 10.3390/jof7121022] [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: 11/07/2021] [Revised: 11/27/2021] [Accepted: 11/27/2021] [Indexed: 11/20/2022] Open
Abstract
Industrial effluents from chromium-based products lead to chromium pollution in the environment. Several technologies have been employed for the removal of chromium (Cr) from the environment, including adsorption, ion-exchange, bioremediation, etc. In this study, we isolated a Cr (VI)-resistant fungus, Purpureocillium lilacinum, from contaminated soil, which could reduce chromium. We also characterized a reductant activity of dichromate found in the cellular fraction of the fungus: optimal pH and temperature, effect of enzymatic inhibitors and enhancers, metal ions, use of electron donors, and initial Cr (VI) and protein concentration. This study also shows possible mechanisms that could be involved in the elimination of this metal. We observed an increase in the reduction of Cr (VI) activity in the presence of NADH followed by that of formate and acetate, as electron donor. This reduction was highly inhibited by EDTA followed by NaN3 and KCN, and this activity showed the highest activity at an optimal pH of 7.0 at 37 °C with a protein concentration of 3.62 µg/mL.
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10
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Huang Y, Zeng Q, Hu L, Zhong H, He Z. Bioreduction performances and mechanisms of Cr(VI) by Sporosarcina saromensis W5, a novel Cr(VI)-reducing facultative anaerobic bacteria. JOURNAL OF HAZARDOUS MATERIALS 2021; 413:125411. [PMID: 33609863 DOI: 10.1016/j.jhazmat.2021.125411] [Citation(s) in RCA: 43] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/29/2020] [Revised: 02/02/2021] [Accepted: 02/10/2021] [Indexed: 06/12/2023]
Abstract
This study reported a novel facultative anaerobic Cr(VI)-reducing bacteria (Sporosarcina saromensis W5) and investigated its Cr(VI) removal performances and removal mechanisms. The strain W5 was able to grow and reduce Cr(VI) under aerobic and anaerobic environment, and exhibited considerable Cr(VI) reduction capabilities under a wide range of pH (8.0-13.0), temperature (20-40 °C) and initial Cr(VI) concentration (50-800 mg/L). The addition of Cd2+ severely inhibited its growth and Cr(VI) removal, while Cu2+ and Fe3+ significantly enhanced the removal efficiencies. The strain W5 could utilize various electron donors and mediators to accelerate Cr(VI) reduction. Aerobic Cr(VI) reduction mainly occurred in cytoplasm and the final products were soluble organo-Cr(III) complexes. Anaerobic Cr(VI) reduction was located in both cytoplasm and membrane, and the reduction products were soluble organo-Cr(III) complexes and Cr(III) precipitates. The functional groups of hydroxyl, carboxyl and phosphoryl on cell surface participated in the combination with Cr(III). Due to its facultative anaerobic property, S. saromensis W5 offers itself as a promising engineering strain for the bioremediation of Cr(VI)-contaminated areas, especially in hypoxia environments.
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Affiliation(s)
- Yongji Huang
- School of Minerals Processing and Bioengineering, Key Laboratory of Biohydrometallurgy of Ministry of Education, Central South University, Changsha 410083, China
| | - Qiang Zeng
- School of Minerals Processing and Bioengineering, Key Laboratory of Biohydrometallurgy of Ministry of Education, Central South University, Changsha 410083, China
| | - Liang Hu
- School of Minerals Processing and Bioengineering, Key Laboratory of Biohydrometallurgy of Ministry of Education, Central South University, Changsha 410083, China
| | - Hui Zhong
- School of Life Science, Central South University, Changsha 410012, China.
| | - Zhiguo He
- School of Minerals Processing and Bioengineering, Key Laboratory of Biohydrometallurgy of Ministry of Education, Central South University, Changsha 410083, China.
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11
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Yu R, Man M, Yu Z, Wu X, Shen L, Liu Y, Li J, Xia M, Zeng W. A high-efficiency Klebsiella variicola H12-CMC-FeS@biochar for chromium removal from aqueous solution. Sci Rep 2021; 11:6611. [PMID: 33758257 PMCID: PMC7988177 DOI: 10.1038/s41598-021-85975-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2020] [Accepted: 03/09/2021] [Indexed: 11/24/2022] Open
Abstract
In polluted groundwater, surface water, and industrial sites, chromium is found as one of the most common heavy metals, and one of the 20 main pollutants in China, which poses a great threat to the ecological environment and human health. Combining biological and chemical materials to treat groundwater contaminated by heavy metals is a promising restoration technology. In this research, Klebsiella variicola H12 (abbreviated as K. variicola) was found to have Cr(VI) reduction ability. A high-efficiency Klebsiella variicola H12-carboxymethyl cellulose (abbreviated as CMC)-FeS@biochar system was established for Cr(VI) removal from aqueous solution. The Scanning Electron Microscope-Energy Dispersive Spectrometer (SEM-EDS), X-ray photoelectron spectroscopy (XPS) results indicated that CMC-FeS was successfully loaded onto the surface of biochar, and K. variicola H12 grew well in the presence of CMC-FeS@biochar with microbial biomass up to 4.8 × 108 cells mL-1. Cr(VI) removal rate of CMC-FeS@biochar system, K. variicola H12 system and K. variicola H12 + CMC-FeS@biochar system were 61.8%, 82.2% and 96.6% respectively. This study demonstrated K. variicola H12-CMC-FeS@biochar system have potential value for efficient removal of Cr(VI) from Cr(VI)-polluted groundwater.
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Affiliation(s)
- Runlan Yu
- School of Minerals Processing and Bioengineering, Central South University, Changsha, 410083, China
- Key Laboratory of Biometallurgy, Ministry of Education, Changsha, 410083, China
| | - Meilian Man
- School of Minerals Processing and Bioengineering, Central South University, Changsha, 410083, China
| | - Zhaojing Yu
- School of Minerals Processing and Bioengineering, Central South University, Changsha, 410083, China
| | - Xueling Wu
- School of Minerals Processing and Bioengineering, Central South University, Changsha, 410083, China
- Key Laboratory of Biometallurgy, Ministry of Education, Changsha, 410083, China
| | - Li Shen
- School of Minerals Processing and Bioengineering, Central South University, Changsha, 410083, China.
- Key Laboratory of Biometallurgy, Ministry of Education, Changsha, 410083, China.
| | - Yuandong Liu
- School of Minerals Processing and Bioengineering, Central South University, Changsha, 410083, China
- Key Laboratory of Biometallurgy, Ministry of Education, Changsha, 410083, China
| | - Jiaokun Li
- School of Minerals Processing and Bioengineering, Central South University, Changsha, 410083, China
- Key Laboratory of Biometallurgy, Ministry of Education, Changsha, 410083, China
| | - Mingchen Xia
- School of Minerals Processing and Bioengineering, Central South University, Changsha, 410083, China
| | - Weimin Zeng
- School of Minerals Processing and Bioengineering, Central South University, Changsha, 410083, China.
- Key Laboratory of Biometallurgy, Ministry of Education, Changsha, 410083, China.
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12
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Uhlein GJ, Caxito FA, Frei R, Uhlein A, Sial AN, Dantas EL. Microbially induced chromium isotope fractionation and trace elements behavior in lower Cambrian microbialites from the Jaíba Member, Bambuí Basin, Brazil. GEOBIOLOGY 2021; 19:125-146. [PMID: 33347697 DOI: 10.1111/gbi.12426] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2020] [Revised: 10/29/2020] [Accepted: 11/29/2020] [Indexed: 06/12/2023]
Abstract
In east-central Brazil, the Ediacaran-Cambrian Bambuí Basin has the potential to provide a record of unique geochemical responses of Earth's ocean and atmosphere evolution during this key time interval. From this perspective, we studied an interval of the upper Bambuí Basin using sedimentologic, stratigraphic, and chemostratigraphic tools. The lower Cambrian Jaíba Member of the uppermost Serra da Saudade Formation is an interval of up to 60 m-thick of carbonate rocks disposed into two shallowing upward trends. Inner to outer ramp and high-energy shoal deposits are described, in which laminated microbialites are the prevailing sedimentary facies. REE + Y data suggest contamination by iron (oxy)hydroxides that are dissociated from the riverine detritic flux. Sedimentary iron enrichment may be related to the settling of iron nanoparticles in coastal environments, diagenetic iron mobilization, or both. MREE enrichment is caused by microbial degradation of organic matter in the iron reduction zone during the anoxic early-diagenetic stage. Chromium isotopes yielded negatively fractionated values (δ53 Cr = -0.69 to -0.27‰), probably resulting from biotic and abiotic reduction of dissolved Cr(VI) to light and less toxic Cr(III) within pores of microbial mats. The δ53 Cr data of the Jaíba microbialite are thus a product of metabolic reactions in microbial mats and do not reflect seawater signal. The isotopic offset from seawater is feasible from molecular diffusion of Cr into pore water and reduction reactions occurring deep inside the mat, although the exact mechanism and consequences are not yet fully understood due to the poor preservation of metabolic reactions in the geological record. Our study suggests that Cr isotopes can be used to reconstruct Cr and other metals cycling within ancient microbial mats, and that caution should be taken when using past microbialites to infer seawater Cr records and redox state of the atmosphere and ocean.
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Affiliation(s)
- Gabriel J Uhlein
- Centro de Pesquisas Manoel Teixeira da Costa, Instituto de Geociências, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Fabrício A Caxito
- Centro de Pesquisas Manoel Teixeira da Costa, Instituto de Geociências, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Robert Frei
- Department of Geoscience and Natural Resource Management, University of Copenhagen, Copenhagen, Denmark
| | - Alexandre Uhlein
- Centro de Pesquisas Manoel Teixeira da Costa, Instituto de Geociências, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Alcides N Sial
- Departamento de Geologia, NEG-LABISE, Universidade Federal de Pernambuco, Recife, Brazil
| | - Elton L Dantas
- Instituto de Geociências, Universidade de Brasília, Brasília, Brazil
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Microbial Mechanisms for Remediation of Hexavalent Chromium and their Large-Scale Applications; Current Research and Future Directions. JOURNAL OF PURE AND APPLIED MICROBIOLOGY 2021. [DOI: 10.22207/jpam.15.1.32] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The increase of anthropogenic activities has led to the pollution of the environment by heavy metals, including chromium (Cr). There are two common oxidative states of Cr that can be found in industrial effluents the trivalent chromium Cr(III) and the hexavalent chromium Cr(VI). While the hexavalent chromium Cr(VI) is highly toxic and can trigger serious human health issues, its reduced form, the trivalent chromium Cr(III), is less toxic and insoluble. Leather tanning is an important industry in many developing countries and serves as a major source of Cr(VI) contamination. Globally, tannery factories generate approximately 40 million m3 of Cr-containing wastewater annually. While the physico-chemical treatments of tannery wastewater are not safe, produce toxic chemicals and require large amounts of chemical inputs, bioremediation using chromium-resistant bacteria (CRB) is safer, efficient and does not produce toxic intermediates. Chromium-resistant bacteria (CRB) utilise three mechanisms for Cr(VI) removal: biotransformation, biosorption and bioaccumulation. This review will evaluate the three Cr(VI) detoxification mechanisms used by bacteria, their limitations and assess their applications for large-scale remediation of Cr(VI). This can be helpful for understanding the nature of Cr(VI) remediation mechanisms used by bacteria, therefore, bridging the gap between laboratory findings and industrial application of microorganisms for Cr(VI) removal.
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Rahman Z, Singh VP. Bioremediation of toxic heavy metals (THMs) contaminated sites: concepts, applications and challenges. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:27563-27581. [PMID: 32418096 DOI: 10.1007/s11356-020-08903-0] [Citation(s) in RCA: 59] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Accepted: 04/15/2020] [Indexed: 06/11/2023]
Abstract
Heavy metal contamination is a global issue, where the prevalent contaminants are arsenic (As), cadmium (Cd), chromium (Cr)(VI), mercury (Hg), and lead (Pb). More often, they are collectively known as "most problematic heavy metals" and "toxic heavy metals" (THMs). Their treatment through a variety of biological processes is one of the prime interests in remediation studies, where heavy metal-microbe interaction approaches receive high interest for their cost effective and ecofriendly solutions. In this review, we provide an up to date information on different microbial processes (bioremediation) for the removal of THMs. For the same, emphasis is put on oxidation-reduction, biomineralization, bioprecipitation, bioleaching, biosurfactant technology, biovolatilization, biosorption, bioaccumulation, and microbe-assisted phytoremediation with their selective advantages and disadvantages. Further, the literature briefly discusses about the various setups of cleaning processes of THMs in environment under ex situ and in situ applications. Lately, the study sheds light on the manipulation of microorganisms through genetic engineering and nanotechnology for their advanced treatment approaches.
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Affiliation(s)
- Zeeshanur Rahman
- Department of Botany, Zakir Husain Delhi College, University of Delhi, Delhi, India.
- Department of Botany, University of Delhi, Delhi, India.
| | - Ved Pal Singh
- Department of Botany, University of Delhi, Delhi, India
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15
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Evaluation of mtr cluster expression in Shewanella RCRI7 during uranium removal. Arch Microbiol 2020; 202:2711-2726. [DOI: 10.1007/s00203-020-01981-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2020] [Revised: 07/03/2020] [Accepted: 07/10/2020] [Indexed: 11/30/2022]
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16
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Mohamed A, Yu L, Fang Y, Ashry N, Riahi Y, Uddin I, Dai K, Huang Q. Iron mineral-humic acid complex enhanced Cr(VI) reduction by Shewanella oneidensis MR-1. CHEMOSPHERE 2020; 247:125902. [PMID: 31978657 DOI: 10.1016/j.chemosphere.2020.125902] [Citation(s) in RCA: 42] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2019] [Revised: 01/07/2020] [Accepted: 01/11/2020] [Indexed: 06/10/2023]
Abstract
Microorganisms, iron minerals, and humic acid are widely common in the soil and water environment and closely interact within environmental processes. In this study, the Cr(VI) removal by Shewanella oneidensis MR-1 (S. oneidensis) was examined in the presence of goethite and humic acid (HA) to mimic the real environment situation. Scanning electron microscopy (SEM) combined with energy disperse spectroscopy (EDS), X-ray photoelectron spectroscopy (XPS), and electron paramagnetic resonance (EPR) technologies were used to probe the Cr(VI) reduction mechanism. Our results showed that S. oneidensis alone could reduce 65% of 1.0 mM Cr(VI) after 8 h of the reduction process. Meanwhile, Cr(VI) reduction rate was declined to 56% in the presence of goethite or humic acid. Contrary, the Cr(VI) reduction rate was mightily increased to 79% by the ternary complex of S. oneidensis-goethite-HA where reduced humic acid (HAred) acted as electron shuttles and diminished the bacterial adhesion to the goethite surface thereby enhanced electron transfer and increased the extent of Cr(VI) reduction by 1.3 fold. XPS analysis indicated that Cr(VI) was reduced to Cr(III), and the final yields were Cr(OH)3 and Cr2O3 precipitated on the surface of bacterial cells. S. oneidensis could also reduce Fe(III) in goethite to Fe(II), which in turn reduced Cr(VI). These results suggested that iron mineral-humic acid complex could enhance the microbial reduction of Cr(VI) and revealed the promotion role of HA in the Cr(VI) bioreduction process. This study affords inclusive insights on the Cr(VI) reduction kinetics and mechanisms in the most complicated systems.
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Affiliation(s)
- Abdelkader Mohamed
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs, College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, PR China; Soil and Water Research Department, Nuclear Research Center, Atomic Energy Authority, Abou Zaabl, 13759, Egypt
| | - Lu Yu
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs, College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Yu Fang
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs, College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Noha Ashry
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs, College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Yassine Riahi
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs, College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Intisar Uddin
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs, College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, PR China
| | - Ke Dai
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs, College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, PR China.
| | - Qiaoyun Huang
- Key Laboratory of Arable Land Conservation (Middle and Lower Reaches of Yangtze River), Ministry of Agriculture and Rural Affairs, College of Resources and Environment, Huazhong Agricultural University, Wuhan, 430070, PR China
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17
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Multi-responsive molecular switch based on a novel photochromic diarylethene derivative bearing a benzocoumarin unit. Tetrahedron 2020. [DOI: 10.1016/j.tet.2020.130955] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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18
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Cheng ZH, Xiong JR, Min D, Cheng L, Liu DF, Li WW, Jin F, Yang M, Yu HQ. Promoting bidirectional extracellular electron transfer of Shewanella oneidensis MR-1 for hexavalent chromium reduction via elevating intracellular cAMP level. Biotechnol Bioeng 2020; 117:1294-1303. [PMID: 32048726 DOI: 10.1002/bit.27305] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 01/29/2020] [Accepted: 02/10/2020] [Indexed: 12/29/2022]
Abstract
The bioreduction capacity of Cr(VI) by Shewanella is mainly governed by its bidirectional extracellular electron transfer (EET). However, the low bidirectional EET efficiency restricts its wider applications in remediation of the environments contaminated by Cr(VI). Cyclic adenosine 3',5'-monophosphate (cAMP) commonly exists in Shewanella strains and cAMP-cyclic adenosine 3',5'-monophosphate receptor protein (CRP) system regulates multiple bidirectional EET-related pathways. This inspires us to strengthen the bidirectional EET through elevating the intracellular cAMP level in Shewanella strains. In this study, an exogenous gene encoding adenylate cyclase from the soil bacterium Beggiatoa sp. PS is functionally expressed in Shewanella oneidensis MR-1 (the strain MR-1/pbPAC) and a MR-1 mutant lacking all endogenous adenylate cyclase encoding genes (the strain Δca/pbPAC). The engineered strains exhibit the enhanced bidirectional EET capacities in microbial electrochemical systems compared with their counterparts. Meanwhile, a three times more rapid reduction rate of Cr(VI) is achieved by the strain MR-1/pbPAC than the control in batch experiments. Furthermore, a higher Cr(VI) reduction efficiency is also achieved by the strain MR-1/pbPAC in the Cr(VI)-reducing biocathode experiments. Such a bidirectional enhancement is attributed to the improved production of cAMP-CRP complex, which upregulates the expression levels of the genes encoding the c-type cytochromes and flavins synthetic pathways. Specially, this strategy could be used as a broad-spectrum approach for the other Shewanella strains. Our results demonstrate that elevating the intracellular cAMP levels could be an efficient strategy to enhance the bidirectional EET of Shewanella strains and improve their pollutant transformation capacity.
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Affiliation(s)
- Zhou-Hua Cheng
- School of Life Sciences, University of Science & Technology of China, Hefei, China
| | - Jia-Rui Xiong
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, China
| | - Di Min
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry, University of Science & Technology of China, Hefei, China
| | - Lei Cheng
- School of Life Sciences, University of Science & Technology of China, Hefei, China
| | - Dong-Feng Liu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry, University of Science & Technology of China, Hefei, China
| | - Wen-Wei Li
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry, University of Science & Technology of China, Hefei, China
| | - Fan Jin
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, China
| | - Min Yang
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China
| | - Han-Qing Yu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry, University of Science & Technology of China, Hefei, China
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19
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Regulation and Maturation of the Shewanella oneidensis Sulfite Reductase SirA. Sci Rep 2020; 10:953. [PMID: 31969587 PMCID: PMC6976685 DOI: 10.1038/s41598-020-57587-6] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2019] [Accepted: 12/27/2019] [Indexed: 01/12/2023] Open
Abstract
Shewanella oneidensis, a metal reducer and facultative anaerobe, expresses a large number of c-type cytochromes, many of which function as anaerobic reductases. All of these proteins contain the typical heme-binding motif CXXCH and require the Ccm proteins for maturation. Two c-type cytochrome reductases also possess atypical heme-binding sites, the NrfA nitrite reductase (CXXCK) and the SirA sulfite reductase (CX12NKGCH). S. oneidensis MR-1 encodes two cytochrome c synthetases (CcmF and SirE) and two apocytochrome c chaperones (CcmI and SirG). SirE located in the sir gene cluster is required for the maturation of SirA, but not NrfA. Here we show that maturation of SirA requires the combined function of the two apocytochrome c chaperones CcmI and SirG. Loss of either protein resulted in decreased sulfite reductase. Furthermore, SirA was not detected in a mutant that lacked both chaperones, perhaps due to misfolding or instability. These results suggest that CcmI interacts with SirEFG during SirA maturation, and with CcmF during maturation of NrfA. Additionally, we show that CRP regulates expression of sirA via the newly identified transcriptional regulatory protein, SirR.
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20
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Mengke-Li, Yuting-Zhuo, Yuting-Hu, Shuzhen-Li, Liang-Hu, Hui-Zhong, Zhiguo-He. Exploration on the bioreduction mechanism of Cr(Ⅵ) by a gram-positive bacterium: Pseudochrobactrum saccharolyticum W1. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2019; 184:109636. [PMID: 31536849 DOI: 10.1016/j.ecoenv.2019.109636] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Revised: 08/30/2019] [Accepted: 09/03/2019] [Indexed: 06/10/2023]
Abstract
Bioremediation of chromium (Cr(Ⅵ)) contaminations has been widely reported, but the research on its removal mechanism is still scarce. Studies on Cr(Ⅵ) removal by strains affiliated to genus Pseudochobactrum revealed the Cr(Ⅵ) efficiency removal through the reduction of Cr(Ⅵ) to Cr(Ⅲ). However, the location of Cr(Ⅵ) reduction reaction and exact mechanism are still unspecified. In this work, a Gram-positive bacterial strain, Pseudochrobactrum saccharolyticum W1 (P. saccharolyticum W1) was isolated and tested to remove approximately 53.7% of Cr(Ⅵ) (initial concentration was 200 mg L-1) from the MSM medium. Analysis of SEM-EDS and TEM-EDS indicated that chromium-containing particles precipitated both on the cell surface and in the cytoplasm. Batch experiments indicated that the heat-treated bacterial cells almost had no ability to remove Cr(Ⅵ) from solution, while the resting cells could remove 62.0% of Cr(Ⅵ) at the initial concentration of 10 mg L-1. Additionally, at this concentration, 64.8% and 70.8% of Cr(Ⅵ) was reduced by cell envelope components and intracellular soluble substances after 6 h, respectively. These results suggested that the removal of Cr(Ⅵ) by P. saccharolyticum W1 was through direct reduction, which occurred on both cell envelop and cytoplasm. The results also showed that cytoplasm was the main site for Cr(Ⅵ) reduction compared to the cell envelop. Further analysis of FTIR and XPS verified that C-H, C-C, CO, C-OH and C-O-C groups of cells involved in correlation with chromium during Cr(Ⅵ) reduction. The study offered an insight into the Cr(VI) reduction mechanism of P. saccharolyticum W1.
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21
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Liu H, Wang Y, Zhang H, Huang G, Yang Q, Wang Y. Synchronous detoxification and reduction treatment of tannery sludge using Cr (VI) resistant bacterial strains. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 687:34-40. [PMID: 31202011 DOI: 10.1016/j.scitotenv.2019.06.093] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Revised: 05/20/2019] [Accepted: 06/06/2019] [Indexed: 06/09/2023]
Abstract
This investigation focused on the simultaneous decrease of tannery sludge and the reduction of its high chromium (Cr(VI)) content. This was accomplished through the addition of mixed bacterial strains that were cultured in the laboratory, subsequent to their isolation from tannery sludge. The results indicated that under anaerobic conditions, the amount of the tannery sludge was decreased by 27% with these mixed bacteria. The impacts of various parameters were explored, such as pH, processing duration, strain inoculation, and temperature. Along with the decreased volume of sludge, the Cr(VI) concentration was lowered as well. Among the isolated bacterial strains, WY601 (belonging to Stenotrophomonas sp.) demonstrated the highest Cr(VI) resistance; from an initial concentration of 300 mg L-1, the Cr(VI) level was decreased by 90% within 65 h. Hexavalent chromate reductase was found to be localized primarily within the extracellular membrane or adsorbed to its surface, and a mechanism was proposed for the removal of Cr(VI) via WY601. Further, the WY601 isolate was found to be tolerant to other toxic heavy metals. In summary, the isolated mixed bacterial strains in our study demonstrated a strong potential for the treatment of tannery sludge, as they could simultaneously decrease its volume while lowering high Cr(VI) levels.
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Affiliation(s)
- Haijin Liu
- School of Environment, Henan Normal University, Key Laboratory for Yellow River and Huaihe River Water Environment and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, Xinxiang 453007, PR China.
| | - Yuqian Wang
- School of Environment, Henan Normal University, Key Laboratory for Yellow River and Huaihe River Water Environment and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, Xinxiang 453007, PR China
| | - Hui Zhang
- School of Environment, Henan Normal University, Key Laboratory for Yellow River and Huaihe River Water Environment and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, Xinxiang 453007, PR China
| | - Guangdao Huang
- School of Environment, Henan Normal University, Key Laboratory for Yellow River and Huaihe River Water Environment and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, Xinxiang 453007, PR China; Environmental Protection & Design Institute, Huaqiao University, Quanzhou 362021, PR China
| | - Qingxiang Yang
- College of Life Sciences, Henan Normal University, Xinxiang 453007, PR China.
| | - Yingling Wang
- School of Environment, Henan Normal University, Key Laboratory for Yellow River and Huaihe River Water Environment and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, Xinxiang 453007, PR China; School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang 453003, PR China
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22
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Shewanella decolorationis LDS1 Chromate Resistance. Appl Environ Microbiol 2019; 85:AEM.00777-19. [PMID: 31300400 DOI: 10.1128/aem.00777-19] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2019] [Accepted: 07/05/2019] [Indexed: 11/20/2022] Open
Abstract
The genus Shewanella is well known for its genetic diversity, its outstanding respiratory capacity, and its high potential for bioremediation. Here, a novel strain isolated from sediments of the Indian Ocean was characterized. A 16S rRNA analysis indicated that it belongs to the species Shewanella decolorationis It was named Shewanella decolorationis LDS1. This strain presented an unusual ability to grow efficiently at temperatures from 24°C to 40°C without apparent modifications of its metabolism, as shown by testing respiratory activities or carbon assimilation, and in a wide range of salt concentrations. Moreover, S. decolorationis LDS1 tolerates high chromate concentrations. Indeed, it was able to grow in the presence of 4 mM chromate at 28°C and 3 mM chromate at 40°C. Interestingly, whatever the temperature, when the culture reached the stationary phase, the strain reduced the chromate present in the growth medium. In addition, S. decolorationis LDS1 degrades different toxic dyes, including anthraquinone, triarylmethane, and azo dyes. Thus, compared to Shewanella oneidensis, this strain presented better capacity to cope with various abiotic stresses, particularly at high temperatures. The analysis of genome sequence preliminary data indicated that, in contrast to S. oneidensis and S. decolorationis S12, S. decolorationis LDS1 possesses the phosphorothioate modification machinery that has been described as participating in survival against various abiotic stresses by protecting DNA. We demonstrate that its heterologous production in S. oneidensis allows it to resist higher concentrations of chromate.IMPORTANCE Shewanella species have long been described as interesting microorganisms in regard to their ability to reduce many organic and inorganic compounds, including metals. However, members of the Shewanella genus are often depicted as cold-water microorganisms, although their optimal growth temperature usually ranges from 25 to 28°C under laboratory growth conditions. Shewanella decolorationis LDS1 is highly attractive, since its metabolism allows it to develop efficiently at temperatures from 24 to 40°C, conserving its ability to respire alternative substrates and to reduce toxic compounds such as chromate or toxic dyes. Our results clearly indicate that this novel strain has the potential to be a powerful tool for bioremediation and unveil one of the mechanisms involved in its chromate resistance.
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Huang XN, Min D, Liu DF, Cheng L, Qian C, Li WW, Yu HQ. Formation mechanism of organo-chromium (III) complexes from bioreduction of chromium (VI) by Aeromonas hydrophila. ENVIRONMENT INTERNATIONAL 2019; 129:86-94. [PMID: 31121519 DOI: 10.1016/j.envint.2019.05.016] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2019] [Revised: 05/06/2019] [Accepted: 05/07/2019] [Indexed: 06/09/2023]
Abstract
Chromium is a common heavy metal widely present in aquatic environments. Cost-effective remediation of chromium-contaminated environment can be realized by microbial reduction of Cr(VI) to Cr(III). The genus Aeromonas species is one of such Cr(VI) reducers, whose reduction mechanism remains unrevealed and the main factors governing the Cr(VI) reduction pathways are unknown yet. In this work, the performances and mechanisms of Cr(VI) anaerobic reduction by Aeromonas hydrophila ATCC 7966 were investigated. This strain exhibited excellent Cr(VI) resistance and could utilize a suite of electron donors to support Cr(VI) bioreduction. The Cr(VI) bioreduction processes involved both extracellular (the metal-reducing and respiratory pathway) and intracellular reaction pathways. Adding anthraquinone-2,6-disulfonate or humic acid as a mediator substantially enhanced the Cr(VI) bioreduction. The forms and distribution of the Cr(VI) bioreduction products were affected by the medium composition. Soluble organo-Cr(III) complexes were identified as the main Cr(VI) reduction products when basal salts medium was adopted. Given the environmental ubiquity of the genus Aeromonas, the findings in this work may facilitate a better understanding about the transformation behaviors and fates of Cr(VI) in environments and provide useful clues to tune the bioremediation of chromium-contaminated environments.
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Affiliation(s)
- Xue-Na Huang
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Di Min
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Dong-Feng Liu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry, University of Science and Technology of China, Hefei 230026, China.
| | - Lei Cheng
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Chen Qian
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Wen-Wei Li
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Han-Qing Yu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry, University of Science and Technology of China, Hefei 230026, China.
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A Novel Bioelectronic Reporter System in Living Cells Tested with a Synthetic Biological Comparator. Sci Rep 2019; 9:7275. [PMID: 31086248 PMCID: PMC6513987 DOI: 10.1038/s41598-019-43771-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 05/01/2019] [Indexed: 12/19/2022] Open
Abstract
As the fields of biotechnology and synthetic biology expand, cheap and sensitive tools are needed to measure increasingly complicated genetic circuits. In order to bypass some drawbacks of optical fluorescent reporting systems, we have designed and created a co-culture microbial fuel cell (MFC) system for electronic reporting. This system leverages the syntrophic growth of Escheriachia. coli (E. coli) and an electrogenic bacterium Shewanella oneidensis MR-1 (S. oneidensis). The fermentative products of E. coli provide a carbon and electron source for S. oneidensis MR-1, which then reports on such activity electrically at the anode of the MFC. To further test the capability of electrical reporting of complicated synthetic circuits, a novel synthetic biological comparator was designed and tested with both fluorescent and electrical reporting systems. The results suggest that the electrical reporting system is a good alternative to commonly used optical fluorescent reporter systems since it is a non-toxic reporting system with a much wider dynamic range.
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Liu X, Chu G, Du Y, Li J, Si Y. The role of electron shuttle enhances Fe(III)-mediated reduction of Cr(VI) by Shewanella oneidensis MR-1. World J Microbiol Biotechnol 2019; 35:64. [DOI: 10.1007/s11274-019-2634-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2018] [Accepted: 03/08/2019] [Indexed: 01/20/2023]
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Zhang Q, Amor K, Galer SJG, Thompson I, Porcelli D. Using stable isotope fractionation factors to identify Cr(VI) reduction pathways: Metal-mineral-microbe interactions. WATER RESEARCH 2019; 151:98-109. [PMID: 30594094 DOI: 10.1016/j.watres.2018.11.088] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/16/2018] [Revised: 11/26/2018] [Accepted: 11/30/2018] [Indexed: 06/09/2023]
Abstract
Microbes interact with metals and minerals in the environment altering their physical and chemical states, whilst in turn metals and minerals impact on microbial growth, activity and survival. The interactions between bacteria and dissolved chromium in the presence of iron minerals, and their impact on Cr isotope variations, were investigated. Cr(VI) reduction experiments were conducted with two bacteria, Pseudomonas fluorescens LB 300 and Shewanella oneidensis MR-1, in the presence of two iron oxide minerals, goethite and hematite. Both minerals were found to inhibit the rates of Cr(VI) reduction by Pseudomonas, but accelerated those of Shewanella. The Cr isotopic fractionation factors generated by Shewanella were independent of the presence of the minerals (ε = -2.3‰). For Pseudomonas, the ε value was the same in both the presence and absence of goethite (-3.3‰); although, it was much higher (ε = -4.3‰) in the presence of hematite. The presence of aqueous Fe(III) in solution had no detectable impact on either bacterial Cr reduction rates nor isotopic fractionation factors. The presence of aqueous Fe(II) induced rapid abiotic reduction of Cr(VI). The different effects that the presence of Fe minerals had on the Cr fractionation factors and reduction rates of the different bacterial species may be attributed to the way each bacteria attached to the minerals and their different reduction pathways. SEM images confirmed that Pseudomonas cells were much more tightly packed on the mineral surfaces than were Shewanella. The images also confirmed that Shewanella oneidensis MR-1 produced nanowires. The results suggest that the dominant Cr(VI) reduction pathway for Pseudomonas fluorescens LB 300 may have been through membrane-bound enzymes, whilst for Shewanella oneidensis MR-1 it was probably via extracellular electron transfer. Since different minerals impact differentially on bacterial Cr(VI) reduction and isotope fractionation, variations of mineralogies and the associated changes of bacterial communities should be taken into consideration when using Cr isotopes to quantify Cr redox behaviour in the environment.
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Affiliation(s)
- Qiong Zhang
- Department of Earth Sciences, University of Oxford, Oxford, United Kingdom.
| | - Ken Amor
- Department of Earth Sciences, University of Oxford, Oxford, United Kingdom
| | - Stephen J G Galer
- Max Planck Institute for Chemistry, Climate Geochemistry Department, 55128, Mainz, Germany
| | - Ian Thompson
- Department of Engineering Science, University of Oxford, Oxford, United Kingdom
| | - Don Porcelli
- Department of Earth Sciences, University of Oxford, Oxford, United Kingdom
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Chen H, Jin R, Liu G, Tian T, Gu C, Zhou J, Xing D. Effects of sludge lysate for Cr(VI) bioreduction and analysis of bioaugmentation mechanism of sludge humic acid. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:5065-5075. [PMID: 30604364 DOI: 10.1007/s11356-018-3917-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 12/04/2018] [Indexed: 06/09/2023]
Abstract
This study evaluated the effects of sludge lysate (SL) on the anaerobic bioreduction of Cr(VI) and the role of sludge humic acid (SHA) during this process. The results showed that supplement of SL significantly enhanced the efficiency of Cr(VI) bioreduction by 29.61%, in 12 h compared with that of the control without SL. Moreover, SHA exhibited promoting effects on bioreduction of Cr(VI), and the promotion increased with increasing SHA concentrations from 100 to 300 mg/L. In the presence of 300 mg/L SHA, Cr(VI) (98.21 mg/L) was completely reduced after 24 h with a removal rate increased by 34.3% compared with that of the control without SHA. Further investigation on the bioaugmentation mechanism of SHA by studying the nature of SHA and the reaction mechanism between SHA and Cr(VI) revealed that SHA exhibited a strong adsorption ability, which could adsorb and combine with Cr(VI). The adsorption capacity of Cr(VI) by SHA was calculated as 34.4 mg/g with 0.2 g of SHA and 10 mg/L of Cr(VI). It could also act as redox mediators to accelerate the electron transfer between microorganisms and Cr(VI) to promote reduction of Cr(VI). Furthermore, the effects of SL on the microbial community compositions of the anaerobic Cr(VI) bioreduction system were studied. Brachymonas was the primary bacteria at the genus level. The abundance of electroactive bacteria, such as Acinetobacter, Pseudomonas, and Arcobacter, increased in the SL-amended system. These findings expand the versatility of SL and justify wider use of residual activated sludge, which might contribute to the treatment of heavy metal-contaminated wastewater.
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Affiliation(s)
- Hongling Chen
- Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China
- Drainage Management Office, Tongliao Municipal Commission of Housing Urban-Rural Development, Tongliao, 028000, China
| | - Ruofei Jin
- Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China.
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China.
| | - Guangfei Liu
- Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China
| | - Tian Tian
- Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China
| | - Chen Gu
- Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China
| | - Jiti Zhou
- Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China
| | - Defeng Xing
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China.
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Li M, He Z, Hu Y, Hu L, Zhong H. Both cell envelope and cytoplasm were the locations for chromium(VI) reduction by Bacillus sp. M6. BIORESOURCE TECHNOLOGY 2019; 273:130-135. [PMID: 30423496 DOI: 10.1016/j.biortech.2018.11.006] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2018] [Revised: 10/30/2018] [Accepted: 11/02/2018] [Indexed: 06/09/2023]
Abstract
Biotreatment is an effective way in remediation of chromium(VI) (Cr(VI)) contamination, but its mechanism and reaction sites are still not clear. Herein, Bacillus sp. M6 was used as a model bacterium in this study to investigate the removal mechanism of Cr(VI) in solution. The results showed that the removal of Cr(VI) was attributed to direct reduction by Bacillus sp. M6, and the reduction locations occurred both on the cell envelope and in the cytoplasm. Meanwhile, bioanalysis of Bacillus sp. M6 by SEM-EDS and TEM-EDS, indicated that Cr(III)-containing precipitates distributed both on the surface and in the cytoplasm of Bacillus sp. In addition, XPS analysis demonstrated that the chromium could be bound to cells by coordination with functional groups (C-based and O-based) on the bacterial surface. This work offers a new and deep insight into the mechanism of Cr(VI) reduction by Bacillus sp.
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Affiliation(s)
- Mengke Li
- School of Minerals Processing and Bioengineering, Key Laboratory of Biohydrometallurgy of Ministry of Education, Central South University, Changsha 410083, China
| | - Zhiguo He
- School of Minerals Processing and Bioengineering, Key Laboratory of Biohydrometallurgy of Ministry of Education, Central South University, Changsha 410083, China
| | - Yuting Hu
- School of Minerals Processing and Bioengineering, Key Laboratory of Biohydrometallurgy of Ministry of Education, Central South University, Changsha 410083, China
| | - Liang Hu
- School of Minerals Processing and Bioengineering, Key Laboratory of Biohydrometallurgy of Ministry of Education, Central South University, Changsha 410083, China
| | - Hui Zhong
- School of Life Science, Central South University, Changsha 410012, China.
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Chen G, Han J, Mu Y, Yu H, Qin L. Two-stage chromium isotope fractionation during microbial Cr(VI) reduction. WATER RESEARCH 2019; 148:10-18. [PMID: 30343194 DOI: 10.1016/j.watres.2018.09.034] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 09/17/2018] [Accepted: 09/18/2018] [Indexed: 06/08/2023]
Abstract
Chromium isotope fractionation analysis is a promising approach for the assessment of microbial Cr(VI) reduction in groundwater. Understanding the mechanisms and other parameters that control Cr isotope fractionation factors (between the product Cr(III) and reactant Cr (VI)) in microbial Cr(VI) reduction is critical to this application. To date, such studies are very limited. Here, the influence of critical factors on observed Cr isotope fractionation during Cr(VI) reduction by Shewanella oneidensis MR-1 under various conditions was investigated. The Cr(VI) concentration and Cr isotope ratio measurements were conducted on unreacted Cr(VI) remaining in solution to determine Cr isotope fractionation factors. The changes in ambient environmental conditions (e.g., pH, temperature) have limited influence on Cr isotope fractionation factors. However, as a result of Cr(VI) consumption as the experiments proceed, the change in bioavailability of Cr(VI) has a significant impact on Cr isotope fractionation factors. For example, in temperature-controlled experiments, Cr isotope fractionation showed two-stage behavior: during Stage I, the values of ε were -2.81 ± 0.19‰ and -2.60 ± 0.14‰ at 18 °C and 34 °C, respectively; during Stage II, as Cr(VI) reduction progressed, Cr isotope fractionation was significantly masked, and the ε values decreased to -0.98 ± 0.49‰ and -1.01 ± 0.11‰ at 18 °C and 34 °C, respectively. Similar two-stage isotope fractionation behaviors were observed in pH-controlled experiments (pH = 6.0 and 7.2) and in experiments with and without the addition of a competing electron acceptor (nitrate). Masking of isotope fractionation in Stage II indicated restrictions on the bioavailability of Cr(VI) and mass-transfer limitations. This study provides an explanation for the variation in Cr isotope fractionation factors during microbial Cr(VI) reduction in the environment, furthering the viability of Cr isotope ratio analysis as an approach in understanding Cr biogeochemical cycling.
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Affiliation(s)
- Guojun Chen
- CAS Key Laboratory of Crust-Mantle Materials and Environments, School of Earth and Space Sciences, University of Science and Technology of China, Hefei, 230026, China
| | - Juncheng Han
- CAS Key Laboratory for Urban Pollutant Conversion, Department of Chemistry, University of Science & Technology of China, Hefei, 230026, China
| | - Yang Mu
- CAS Key Laboratory for Urban Pollutant Conversion, Department of Chemistry, University of Science & Technology of China, Hefei, 230026, China
| | - Huimin Yu
- CAS Key Laboratory of Crust-Mantle Materials and Environments, School of Earth and Space Sciences, University of Science and Technology of China, Hefei, 230026, China
| | - Liping Qin
- CAS Key Laboratory of Crust-Mantle Materials and Environments, School of Earth and Space Sciences, University of Science and Technology of China, Hefei, 230026, China; State Key Laboratory of Geological Processes and Mineral Resources, University of Geosciences, Beijing, China.
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Using metabolic charge production in the tricarboxylic acid cycle (Q TCA) to evaluate the extracellular-electron-transfer performances of Shewanella spp. Bioelectrochemistry 2018; 124:119-126. [PMID: 30015268 DOI: 10.1016/j.bioelechem.2018.07.001] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2018] [Revised: 06/24/2018] [Accepted: 07/03/2018] [Indexed: 01/13/2023]
Abstract
Using an electrochemical cell equipped with carbon felt electrodes (poised at +0.63 V vs. SHE), the current production capabilities of two Shewanella strains-NTOU1 and KR-12-were examined under various conditions with lactate as an electron donor. The metabolic charge produced in the tricarboxylic acid cycle (QTCA) was calculated by mass-balance. The data showed a linear relation between the electric coulomb production (QEL) and QTCA with an R2 of 0.65. In addition, a large amount of pyruvate accumulation was observed at pH = 6, rendering QTCA negative. The results indicate an occurrence of an undesired cataplerotic reaction. It was also found that QTCA provides important information showing the oxygen-boosting TCA cycle and anodic-current generation of Shewanella spp. Linear dependence of the change in charge for biomass growth (4.52FΔnCell) on QTCA was also found as expressed by 4.52FΔnCell = 1.0428 QTCA + 0.0442, indicating that these two charge quantities are inherently identical under most of the experimental conditions. In the mediator-spiked experiments, the external addition of the mediators (ferricyanide, anthraquinone-2, 6-disulfonate, and riboflavin) beyond certain concentrations inhibited the activity of the TCA cycle, indicating that the oxidative phosphorylation is deactivated by excessive amounts of mediators, yet Shewanella spp. are constrained with regard to carrying out the substrate-level phosphorylation.
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Bennett BD, Redford KE, Gralnick JA. MgtE Homolog FicI Acts as a Secondary Ferrous Iron Importer in Shewanella oneidensis Strain MR-1. Appl Environ Microbiol 2018; 84:e01245-17. [PMID: 29330185 PMCID: PMC5835737 DOI: 10.1128/aem.01245-17] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2017] [Accepted: 01/05/2018] [Indexed: 01/28/2023] Open
Abstract
The transport of metals into and out of cells is necessary for the maintenance of appropriate intracellular concentrations. Metals are needed for incorporation into metalloproteins but become toxic at higher concentrations. Many metal transport proteins have been discovered in bacteria, including the Mg2+ transporter E (MgtE) family of passive Mg2+/Co2+ cation-selective channels. Low sequence identity exists between members of the MgtE family, indicating that substrate specificity may differ among MgtE transporters. Under anoxic conditions, dissimilatory metal-reducing bacteria, such as Shewanella and Geobacter species, are exposed to high levels of soluble metals, including Fe2+ and Mn2+ Here we characterize SO_3966, which encodes an MgtE homolog in Shewanella oneidensis that we name FicI (ferrous iron and cobalt importer) based on its role in maintaining metal homeostasis. A SO_3966 deletion mutant exhibits enhanced growth over that of the wild type under conditions with high Fe2+ or Co2+ concentrations but exhibits wild-type Mg2+ transport and retention phenotypes. Conversely, deletion of feoB, which encodes an energy-dependent Fe2+ importer, causes a growth defect under conditions of low Fe2+ concentrations but not high Fe2+ concentrations. We propose that FicI represents a secondary, less energy-dependent mechanism for iron uptake by S. oneidensis under high Fe2+ concentrations.IMPORTANCEShewanella oneidensis MR-1 is a target of microbial engineering for potential uses in biotechnology and the bioremediation of heavy-metal-contaminated environments. A full understanding of the ways in which S. oneidensis interacts with metals, including the means by which it transports metal ions, is important for optimal genetic engineering of this and other organisms for biotechnology purposes such as biosorption. The MgtE family of metal importers has been described previously as Mg2+ and Co2+ transporters. This work broadens that designation with the discovery of an MgtE homolog in S. oneidensis that imports Fe2+ but not Mg2+ The research presented here also expands our knowledge of the means by which microorganisms have adapted to take up essential nutrients such as iron under various conditions.
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Affiliation(s)
- Brittany D Bennett
- BioTechnology Institute and Department of Plant and Microbial Biology, University of Minnesota-Twin Cities, St. Paul, Minnesota, USA
| | - Kaitlyn E Redford
- BioTechnology Institute and Department of Plant and Microbial Biology, University of Minnesota-Twin Cities, St. Paul, Minnesota, USA
| | - Jeffrey A Gralnick
- BioTechnology Institute and Department of Plant and Microbial Biology, University of Minnesota-Twin Cities, St. Paul, Minnesota, USA
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32
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Bai YN, Lu YZ, Shen N, Lau TC, Zeng RJ. Investigation of Cr(VI) reduction potential and mechanism by Caldicellulosiruptor saccharolyticus under glucose fermentation condition. JOURNAL OF HAZARDOUS MATERIALS 2018; 344:585-592. [PMID: 29102641 DOI: 10.1016/j.jhazmat.2017.10.059] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 10/25/2017] [Accepted: 10/28/2017] [Indexed: 06/07/2023]
Abstract
This study examined the microbial reduction of hexavalent chromium [Cr(VI)] by an extremely thermophilic bacterium, Caldicellulosiruptor saccharolyticus, under glucose fermentation conditions at 70°C. Experimentation with different initial Cr(VI) concentrations confirmed that C. saccharolyticus had the ability to reduce Cr(VI) and immobilize Cr(III). At a concentration of 40mg/L, Cr(VI) was completely reduced within 12h, and 97% of the reduction product Cr(III) precipitated on the cell surface. Cr(VI) reduction was accelerated by the addition of neutral red (NR, an electron mediator), resulting in the reduction time shortened to 1h. The addition of CuCl2, a Ni-Fe hydrogenase inhibitor, also enhanced Cr(VI) reduction. Additionally, analysis of the relationship between Cr(VI) reduction and glucose fermentation suggested that different electron sources acted during CuCl2 and NR conditions. Hydrogen served as an electron donor under normal fermentation and NR conditions with the catalysis of Ni-Fe hydrogenase. However, when the activity of Ni-Fe hydrogenase was inhibited by CuCl2, C. saccharolyticus directly used reduction equivalents during glucose fermentation for intracellular Cr(VI) reduction. Therefore, our findings demonstrated high Cr(VI) reduction ability and different electron transfer pathways during Cr(VI) reduction by C. saccharolyticus.
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Affiliation(s)
- Ya-Nan Bai
- Advanced Laboratory for Environmental Research and Technology, USTC-CityU, Suzhou, PR China; School of Life Sciences, University of Science and Technology of China, Hefei 230026, PR China
| | - Yong-Ze Lu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei 230026, PR China
| | - Nan Shen
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei 230026, PR China
| | - Tai-Chu Lau
- Advanced Laboratory for Environmental Research and Technology, USTC-CityU, Suzhou, PR China; State Key Laboratory in Marine Pollution, Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong
| | - Raymond Jianxiong Zeng
- Advanced Laboratory for Environmental Research and Technology, USTC-CityU, Suzhou, PR China; School of Life Sciences, University of Science and Technology of China, Hefei 230026, PR China; CAS Key Laboratory of Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei 230026, PR China.
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Baldiris R, Acosta-Tapia N, Montes A, Hernández J, Vivas-Reyes R. Reduction of Hexavalent Chromium and Detection of Chromate Reductase (ChrR) in Stenotrophomonas maltophilia. Molecules 2018; 23:E406. [PMID: 29438314 PMCID: PMC6017488 DOI: 10.3390/molecules23020406] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Revised: 01/31/2018] [Accepted: 02/03/2018] [Indexed: 12/30/2022] Open
Abstract
An Gram negative strain of S. maltophilia, indigenous to environments contaminated by Cr(VI) and identified by biochemical methods and 16S rRNA gene analysis, reduced chromate by 100%, 98-99% and 92% at concentrations in the 10-70, 80-300, and 500 mg/L range, respectively at pH 7 and temperature 37 °C. Increasing concentrations of Cr(VI) in the medium lowered the growth rate but could not be directly correlated with the amount of Cr(VI) reduced. The strain also exhibited multiple resistance to antibiotics and tolerance and resistance to various heavy metals (Ni, Zn and Cu), with the exception of Hg. Hexavalent chromium reduction was mainly associated with the soluble fraction of the cell evaluated with crude cell-free extracts. A protein of molecular weight around 25 kDa was detected on SDS-PAGE gel depending on the concentration of hexavalent chromium in the medium (0, 100 and 500 mg/L). In silico analysis in this contribution, revealed the presence of the chromate reductase gene ChrR in S. maltophilia, evidenced through a fragment of around 468 bp obtained experimentally. High Cr(VI) concentration resistance and high Cr(VI) reducing ability of the strain make it a suitable candidate for bioremediation.
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Affiliation(s)
- Rosa Baldiris
- Grupo de Microbiología Clínica y Ambiental, Facultad de Ciencias Exactas y Naturales, Programa de Biología, Universidad de Cartagena, Campus San Pablo, Cartagena 130015, Colombia.
- Grupo de Investigación CIPTEC, Facultad de Ingeniería, Programa de Ingeniería de Procesos, Fundación Universitaria Tecnológico Comfenalco, Cartagena 130015, Colombia.
| | - Natali Acosta-Tapia
- Grupo de Microbiología Clínica y Ambiental, Facultad de Ciencias Exactas y Naturales, Programa de Biología, Universidad de Cartagena, Campus San Pablo, Cartagena 130015, Colombia.
- Grupo de Investigación CIPTEC, Facultad de Ingeniería, Programa de Ingeniería de Procesos, Fundación Universitaria Tecnológico Comfenalco, Cartagena 130015, Colombia.
| | - Alfredo Montes
- Grupo de Microbiología Clínica y Ambiental, Facultad de Ciencias Exactas y Naturales, Programa de Biología, Universidad de Cartagena, Campus San Pablo, Cartagena 130015, Colombia.
- Grupo de Química Cuántica y Teórica, Facultad de Ciencias Exactas y Naturales, Universidad de TCartagena, Campus, San Pablo, Cartagena 130015, Colombia.
| | - Jennifer Hernández
- Grupo de Química Cuántica y Teórica, Facultad de Ciencias Exactas y Naturales, Universidad de TCartagena, Campus, San Pablo, Cartagena 130015, Colombia.
| | - Ricardo Vivas-Reyes
- Grupo de Investigación CIPTEC, Facultad de Ingeniería, Programa de Ingeniería de Procesos, Fundación Universitaria Tecnológico Comfenalco, Cartagena 130015, Colombia.
- Grupo de Química Cuántica y Teórica, Facultad de Ciencias Exactas y Naturales, Universidad de TCartagena, Campus, San Pablo, Cartagena 130015, Colombia.
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Liu Z, Yang W, Tian B, Liu J, Zhu W, Ge G, Xiao L, Meng Y. Fabrication of a self-assembled supramolecular fluorescent nanosensor from functional graphene oxide and its application for the detection of Al3+. NEW J CHEM 2018. [DOI: 10.1039/c8nj03322f] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
In this work, we present an excellent water-soluble supramolecular self-assembled fluorescent nanosensor toward Al3+based on graphene oxide and a β-cyclodextrin derivative.
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Affiliation(s)
- Zengchen Liu
- College of Chemistry and Chemical Engineering
- Henan Key Laboratory of Rare Earth Functional Materials
- International Joint Research Laboratory for Biomedical Nanomaterials of Henan
- The Key Laboratory of Rare Earth Functional Materials and Applications
- Zhoukou Normal University
| | - Weijie Yang
- College of Chemistry and Chemical Engineering
- Henan Key Laboratory of Rare Earth Functional Materials
- International Joint Research Laboratory for Biomedical Nanomaterials of Henan
- The Key Laboratory of Rare Earth Functional Materials and Applications
- Zhoukou Normal University
| | - Boshi Tian
- College of Chemistry and Chemical Engineering
- Henan Key Laboratory of Rare Earth Functional Materials
- International Joint Research Laboratory for Biomedical Nanomaterials of Henan
- The Key Laboratory of Rare Earth Functional Materials and Applications
- Zhoukou Normal University
| | - Jin Liu
- College of Chemistry and Chemical Engineering
- Henan Key Laboratory of Rare Earth Functional Materials
- International Joint Research Laboratory for Biomedical Nanomaterials of Henan
- The Key Laboratory of Rare Earth Functional Materials and Applications
- Zhoukou Normal University
| | - Wenping Zhu
- College of Chemistry and Chemical Engineering
- Henan Key Laboratory of Rare Earth Functional Materials
- International Joint Research Laboratory for Biomedical Nanomaterials of Henan
- The Key Laboratory of Rare Earth Functional Materials and Applications
- Zhoukou Normal University
| | - Genwu Ge
- College of Chemistry and Chemical Engineering
- Henan Key Laboratory of Rare Earth Functional Materials
- International Joint Research Laboratory for Biomedical Nanomaterials of Henan
- The Key Laboratory of Rare Earth Functional Materials and Applications
- Zhoukou Normal University
| | - Lina Xiao
- College of Chemistry and Chemical Engineering
- Henan Key Laboratory of Rare Earth Functional Materials
- International Joint Research Laboratory for Biomedical Nanomaterials of Henan
- The Key Laboratory of Rare Earth Functional Materials and Applications
- Zhoukou Normal University
| | - Yuning Meng
- College of Chemistry and Chemical Engineering
- Henan Key Laboratory of Rare Earth Functional Materials
- International Joint Research Laboratory for Biomedical Nanomaterials of Henan
- The Key Laboratory of Rare Earth Functional Materials and Applications
- Zhoukou Normal University
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Saigl ZM, Ahmad W, Mohammed GI, Alwael H, Al-Bagawi AH, Al-Eryani DA, El-Shahawi MS. A promazine derivative-oriented chemical sensor for ultra-sensitive chromium determination. NEW J CHEM 2018. [DOI: 10.1039/c7nj05131j] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The study reports a simple and highly selective spectrofluorometric method for trace determination and speciation of chromium(iii & vi) species in water using 10-(3-dimethylaminopropyl) phenothiazine hydrochloride, namely, promazine hydrochloride (PMH) as a fluorescence tagging reagent.
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Affiliation(s)
- Z. M. Saigl
- Department of Chemistry
- Faculty of Science
- King Abdulaziz University
- Jeddah 21589
- Saudi Arabia
| | - W. Ahmad
- Department of Chemistry
- Faculty of Science
- King Abdulaziz University
- Jeddah 21589
- Saudi Arabia
| | - G. I. Mohammed
- Department of Chemistry
- Faculty of Science
- Umm Al Qura University
- Makkah
- Saudi Arabia
| | - H. Alwael
- Department of Chemistry
- Faculty of Science
- King Abdulaziz University
- Jeddah 21589
- Saudi Arabia
| | - A. H. Al-Bagawi
- Department of Chemistry
- Faculty of Science
- Hail University
- Hail
- Saudi Arabia
| | - D. A. Al-Eryani
- Department of Chemistry
- Faculty of Science
- King Abdulaziz University
- Jeddah 21589
- Saudi Arabia
| | - M. S. El-Shahawi
- Department of Chemistry
- Faculty of Science
- King Abdulaziz University
- Jeddah 21589
- Saudi Arabia
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Baaziz H, Gambari C, Boyeldieu A, Ali Chaouche A, Alatou R, Méjean V, Jourlin-Castelli C, Fons M. ChrASO, the chromate efflux pump of Shewanella oneidensis, improves chromate survival and reduction. PLoS One 2017; 12:e0188516. [PMID: 29166414 PMCID: PMC5699817 DOI: 10.1371/journal.pone.0188516] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2017] [Accepted: 11/08/2017] [Indexed: 01/22/2023] Open
Abstract
The chromate efflux pump encoding gene chrASO was identified on the chromosome of Shewanella oneidensis MR1. Although chrASO is expressed without chromate, its expression level increases when Cr(VI) is added. When deleted, the resulting mutant ΔchrASO exhibits a chromate sensitive phenotype compared to that of the wild-type strain. Interestingly, heterologous expression of chrASO in E. coli confers resistance to high chromate concentration. Moreover, expression of chrASO in S. oneidensis and E. coli significantly improves Cr(VI) reduction. This effect could result either from extracytoplasmic chromate reduction or from a better cell survival leading to enhanced Cr(VI) reduction.
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Affiliation(s)
- Hiba Baaziz
- Unité de Bioénergétique et Ingénierie des Protéines, Institut de Microbiologie de la Méditerranée, Aix-Marseille Université, Centre National de la Recherche Scientifique, Marseille, France
- Laboratoire de Biologie Moléculaire et Cellulaire, Université des Frères Mentouri Constantine 1, Constantine, Algeria
| | - Cyril Gambari
- Unité de Bioénergétique et Ingénierie des Protéines, Institut de Microbiologie de la Méditerranée, Aix-Marseille Université, Centre National de la Recherche Scientifique, Marseille, France
| | - Anne Boyeldieu
- Unité de Bioénergétique et Ingénierie des Protéines, Institut de Microbiologie de la Méditerranée, Aix-Marseille Université, Centre National de la Recherche Scientifique, Marseille, France
| | - Amine Ali Chaouche
- Unité de Bioénergétique et Ingénierie des Protéines, Institut de Microbiologie de la Méditerranée, Aix-Marseille Université, Centre National de la Recherche Scientifique, Marseille, France
| | - Radia Alatou
- Laboratoire de Biologie Moléculaire et Cellulaire, Université des Frères Mentouri Constantine 1, Constantine, Algeria
| | - Vincent Méjean
- Unité de Bioénergétique et Ingénierie des Protéines, Institut de Microbiologie de la Méditerranée, Aix-Marseille Université, Centre National de la Recherche Scientifique, Marseille, France
| | - Cécile Jourlin-Castelli
- Unité de Bioénergétique et Ingénierie des Protéines, Institut de Microbiologie de la Méditerranée, Aix-Marseille Université, Centre National de la Recherche Scientifique, Marseille, France
| | - Michel Fons
- Unité de Bioénergétique et Ingénierie des Protéines, Institut de Microbiologie de la Méditerranée, Aix-Marseille Université, Centre National de la Recherche Scientifique, Marseille, France
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Zhong L, Lai CY, Shi LD, Wang KD, Dai YJ, Liu YW, Ma F, Rittmann BE, Zheng P, Zhao HP. Nitrate effects on chromate reduction in a methane-based biofilm. WATER RESEARCH 2017; 115:130-137. [PMID: 28273443 DOI: 10.1016/j.watres.2017.03.003] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Revised: 02/27/2017] [Accepted: 03/01/2017] [Indexed: 06/06/2023]
Abstract
The effects of nitrate (NO3-) on chromate (Cr(VI)) reduction in a membrane biofilm reactor (MBfR) were studied when CH4 was the sole electron donor supplied with a non-limiting delivery capacity. A high surface loading of NO3- gave significant and irreversible inhibition of Cr(VI) reduction. At a surface loading of 500 mg Cr/m2-d, the Cr(VI)-removal percentage was 100% when NO3- was absent (Stage 1), but was dramatically lowered to < 25% with introduction of 280 mg N m-2-d NO3- (Stage 2). After ∼50 days operation in Stage 2, the Cr(VI) reduction recovered to only ∼70% in Stage 3, when NO3- was removed from the influent; thus, NO3- had a significant long-term inhibition effect on Cr(VI) reduction. Weighted PCoA and UniFrac analyses proved that the introduction of NO3- had a strong impact on the microbial community in the biofilms, and the changes possibly were linked to the irreversible inhibition of Cr(VI) reduction. For example, Meiothermus, the main genus involved in Cr(VI) reduction at first, declined with introduction of NO3-. The denitrifier Chitinophagaceae was enriched after the addition of NO3-, while Pelomonas became important when nitrate was removed, suggesting its potential role as a Cr(VI) reducer. Moreover, introducing NO3- led to a decrease in the number of genes predicted (by PICRUSt) to be related to chromate reduction, but genes predicted to be related to denitrification, methane oxidation, and fermentation increased.
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Affiliation(s)
- Liang Zhong
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China
| | - Chun-Yu Lai
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China; Zhejiang Province Key Lab Water Pollut Control & Envi, Zhejiang University, Hangzhou, Zhejiang, China
| | - Ling-Dong Shi
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China
| | - Kai-Di Wang
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China
| | - Yu-Jie Dai
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China
| | - Yao-Wei Liu
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China
| | - Fang Ma
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.
| | - Bruce E Rittmann
- Biodesign Swette Center for Environmental Biotechnology, Arizona State University, P.O. Box 875701, Tempe, AZ 85287-5701, USA
| | - Ping Zheng
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China; Zhejiang Province Key Lab Water Pollut Control & Envi, Zhejiang University, Hangzhou, Zhejiang, China
| | - He-Ping Zhao
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China; Zhejiang Province Key Lab Water Pollut Control & Envi, Zhejiang University, Hangzhou, Zhejiang, China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.
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39
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Yen HW, Chen PW, Hsu CY, Lee L. The use of autotrophic Chlorella vulgaris in chromium (VI) reduction under different reduction conditions. J Taiwan Inst Chem Eng 2017. [DOI: 10.1016/j.jtice.2016.08.017] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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40
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Mansur R, Gusmanizar N, Roslan MAH, Ahmad SA, Shukor MY. Isolation and Characterisation of a Molybdenum-reducing and Metanil Yellow Dye-decolourising Bacillus sp. strain Neni-10 in Soils from West Sumatera, Indonesia. Trop Life Sci Res 2017; 28:69-90. [PMID: 28228917 DOI: 10.21315/tlsr2017.28.1.5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
A molybdenum reducing bacterium with the novel ability to decolorise the azo dye Metanil Yellow is reported. Optimal conditions for molybdenum reduction were pH 6.3 and at 34°C. Glucose was the best electron donor. Another requirement includes a narrow phosphate concentration between 2.5 and 7.5 mM. A time profile of Mo-blue production shows a lag period of approximately 12 hours, a maximum amount of Mo-blue produced at a molybdate concentration of 20 mM, and a peak production at 52 h of incubation. The heavy metals mercury, silver, copper and chromium inhibited reduction by 91.9, 82.7, 45.5 and 17.4%, respectively. A complete decolourisation of the dye Metanil Yellow at 100 and 150 mg/L occurred at day three and day six of incubations, respectively. Higher concentrations show partial degradation, with an approximately 20% decolourisation observed at 400 mg/L. The bacterium is partially identified based on biochemical analysis as Bacillus sp. strain Neni-10. The absorption spectrum of the Mo-blue suggested the compound is a reduced phosphomolybdate. The isolation of this bacterium, which shows heavy metal reduction and dye-decolorising ability, is sought after, particularly for bioremediation.
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Affiliation(s)
- Rusnam Mansur
- Department of Agricultural Engineering, Faculty of Agricultural Technology, Andalas University, Padang 25163, Indonesia
| | - Neni Gusmanizar
- Department of Animal Nutrition, Faculty of Animal Science, Andalas University, Padang 25163, Indonesia; Department of Biochemistry, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
| | - Muhamad Akhmal Hakim Roslan
- Department of Biochemistry, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
| | - Siti Aqlima Ahmad
- Department of Biochemistry, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
| | - Mohd Yunus Shukor
- Department of Biochemistry, Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, 43400 UPM Serdang, Selangor, Malaysia
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41
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Thatoi HN, Pradhan SK. Detoxification and Bioremediation of Hexavalent Chromium Using Microbes and Their Genes: An Insight into Genomic, Proteomic and Bioinformatics Studies. Microb Biotechnol 2017. [DOI: 10.1007/978-981-10-6847-8_13] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
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42
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Ding Y, Zhou Y, Yao J, Szymanski C, Fredrickson J, Shi L, Cao B, Zhu Z, Yu XY. In Situ Molecular Imaging of the Biofilm and Its Matrix. Anal Chem 2016; 88:11244-11252. [DOI: 10.1021/acs.analchem.6b03909] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Yuanzhao Ding
- Singapore
Centre for Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, 637551, Singapore
- Interdisciplinary
Graduate School (IGS), Nanyang Technological University (NTU), 639798, Singapore
- Earth
and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99354, United States
| | - Yufan Zhou
- Environmental
and Molecular Science Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Juan Yao
- Earth
and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99354, United States
| | - Craig Szymanski
- Environmental
and Molecular Science Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - James Fredrickson
- Earth
and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99354, United States
| | - Liang Shi
- Earth
and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99354, United States
| | - Bin Cao
- Singapore
Centre for Environmental Life Sciences Engineering (SCELSE), Nanyang Technological University, 637551, Singapore
- School
of Civil and Environmental Engineering, Nanyang Technological University (NTU), 639798, Singapore
| | - Zihua Zhu
- Environmental
and Molecular Science Laboratory, Pacific Northwest National Laboratory, Richland, Washington 99352, United States
| | - Xiao-Ying Yu
- Earth
and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, Washington 99354, United States
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43
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Cr(VI) removal from aqueous solution by thermophilic denitrifying bacterium Chelatococcus daeguensis TAD1 in the presence of single and multiple heavy metals. J Microbiol 2016; 54:602-610. [DOI: 10.1007/s12275-016-5295-5] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Revised: 07/22/2016] [Accepted: 07/26/2016] [Indexed: 11/25/2022]
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Pandey S, Singh NK, Bansal AK, Arutchelvan V, Sarkar S. Alleviation of toxic hexavalent chromium using indigenous aerobic bacteria isolated from contaminated tannery industry sites. Prep Biochem Biotechnol 2016; 46:517-23. [PMID: 26458110 DOI: 10.1080/10826068.2015.1084635] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
In the last decade, much attention has been paid to bioremediation of Cr(VI) using various bacterial species. Cr(VI) remediation by indegeneous bacteria isolated from contaminated sites of a tannery industry located in Tamil Nadu, India, was investigated in this study. Three Cr(VI) resistant bacterial strains (TES-1, TEf-1, and TES-2) were isolated and selected based on their Cr(VI) reduction ability in minimal salt medium. Among these three bacterial strains, TES-1 was found to be most efficient in bioreduction, while TES-2 was only found to be Cr(VI) resistant and showed negligible bioreduction, whereas TEf-1 was observed to be most Cr(VI) tolerant. Potential for bioremediation of TES-1 and TEf-1 was further investigated at different concentrations of Cr(VI) in the range of 50 to 350 mg L(-1). TEf-1 showed prominent synchronous growth throughout the experiment, whereas TES-1 took a longer acclimatization time. Minimum inhibitory concentrations (MIC) of Cr(VI) for TES-1 and TEf-1 were approximated as 600 mg L(-1) and 750 mg L(-1), respectively. The kinetic behavior of Cr(VI) reduction by TES-1 and TEf-1 exhibited zero- and first-order removal kinetics for Cr(VI), respectively. The most efficient strain TES-1 was identified as Streptomyces sp. by gene sequencing of 16S rRNA.
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Affiliation(s)
- Siddhartha Pandey
- a Department of Civil Engineering , Indian Institute of Technology Roorkee , Roorkee , Uttrakhand , India
| | - Nitin Kumar Singh
- a Department of Civil Engineering , Indian Institute of Technology Roorkee , Roorkee , Uttrakhand , India
| | - Ankur Kumar Bansal
- b Department of Civil Engineering , Moradabad Institute of Technology , Moradabad , Uttar Pradesh , India
| | - V Arutchelvan
- c Department of Civil Engineering , Annamalai University , Annamalai Nagar , Tamil Nadu , India
| | - Sudipta Sarkar
- a Department of Civil Engineering , Indian Institute of Technology Roorkee , Roorkee , Uttrakhand , India
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45
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Han R, Li F, Liu T, Li X, Wu Y, Wang Y, Chen D. Effects of Incubation Conditions on Cr(VI) Reduction by c-type Cytochromes in Intact Shewanella oneidensis MR-1 Cells. Front Microbiol 2016; 7:746. [PMID: 27242759 PMCID: PMC4872037 DOI: 10.3389/fmicb.2016.00746] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2015] [Accepted: 05/03/2016] [Indexed: 11/13/2022] Open
Abstract
It is widely recognized that the outer membrane c-type cytochromes (OM c-Cyts) of metal-reducing bacteria play a key role in microbial metal reduction processes. However, the in situ redox status of OM c-Cyts during microbial metal reduction processes remain poorly understood. In this study, diffuse-transmission UV/Vis spectroscopy is used to investigate the in situ spectral reaction of Cr(VI) reduction by c-Cyts in intact Shewanella oneidensis MR-1 cells under different incubation conditions. The reduced c-Cyts decreased transiently at the beginning and then recovered gradually over time. The Cr(VI) reduction rates decreased with increasing initial Cr(VI) concentrations, and Cr(III) was identified as a reduced product. The presence of Cr(III) substantially inhibited Cr(VI) reduction and the recovery of reduced c-Cyts, indicating that Cr(III) might inhibit cell growth. Cr(VI) reduction rates increased with increasing cell density. The highest Cr(VI) reduction rate and fastest recovery of c-Cyts were obtained at pH 7.0 and 30°C, with sodium lactate serving as an electron donor. The presence of O2 strongly inhibited Cr(VI) reduction, suggesting that O2 might compete with Cr(VI) as an electron acceptor in cells. This study provides a case of directly examining in vivo reaction properties of an outer-membrane enzyme during microbial metal reduction processes under non-invasive physiological conditions.
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Affiliation(s)
- Rui Han
- School of Environment and Energy, South China University of TechnologyGuangzhou, China; Guangdong Key Laboratory of Agricultural Environment Pollution Integrated Control, Guangdong Institute of Eco-Environmental and Soil SciencesGuangzhou, China
| | - Fangbai Li
- Guangdong Key Laboratory of Agricultural Environment Pollution Integrated Control, Guangdong Institute of Eco-Environmental and Soil Sciences Guangzhou, China
| | - Tongxu Liu
- Guangdong Key Laboratory of Agricultural Environment Pollution Integrated Control, Guangdong Institute of Eco-Environmental and Soil Sciences Guangzhou, China
| | - Xiaomin Li
- Guangdong Key Laboratory of Agricultural Environment Pollution Integrated Control, Guangdong Institute of Eco-Environmental and Soil Sciences Guangzhou, China
| | - Yundang Wu
- Guangdong Key Laboratory of Agricultural Environment Pollution Integrated Control, Guangdong Institute of Eco-Environmental and Soil Sciences Guangzhou, China
| | - Ying Wang
- Guangdong Key Laboratory of Agricultural Environment Pollution Integrated Control, Guangdong Institute of Eco-Environmental and Soil Sciences Guangzhou, China
| | - Dandan Chen
- Guangdong Key Laboratory of Agricultural Environment Pollution Integrated Control, Guangdong Institute of Eco-Environmental and Soil Sciences Guangzhou, China
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46
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Formate Metabolism in Shewanella oneidensis Generates Proton Motive Force and Prevents Growth without an Electron Acceptor. J Bacteriol 2016; 198:1337-46. [PMID: 26883823 DOI: 10.1128/jb.00927-15] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2015] [Accepted: 02/08/2016] [Indexed: 11/20/2022] Open
Abstract
UNLABELLED Shewanella oneidensis strain MR-1 is a facultative anaerobe that thrives in redox-stratified environments due to its ability to utilize a wide array of terminal electron acceptors. Conversely, the electron donors utilized by S. oneidensis are more limited and include products of primary fermentation such as lactate, pyruvate, formate, and hydrogen. Lactate, pyruvate, and hydrogen metabolisms inS. oneidensis have been described previously, but little is known about the role of formate oxidation in the ecophysiology of these bacteria. Formate is produced by S. oneidensis through pyruvate formate lyase during anaerobic growth on carbon sources that enter metabolism at or above the level of pyruvate, and the genome contains three gene clusters predicted to encode three complete formate dehydrogenase complexes. To determine the contribution of each complex to formate metabolism, strains lacking one, two, or all three annotated formate dehydrogenase gene clusters were generated and examined for growth rates and yields on a variety of carbon sources. Here, we report that formate oxidation contributes to both the growth rate and yield of S. oneidensis through the generation of proton motive force. Exogenous formate also greatly accelerated growth on N-acetylglucosamine, a carbon source normally utilized very slowly by S. oneidensis under anaerobic conditions. Surprisingly, deletion of all three formate dehydrogenase gene clusters enabled growth of S. oneidensis using pyruvate in the absence of a terminal electron acceptor, a mode of growth never before observed in these bacteria. Our results demonstrate that formate oxidation is a fundamental strategy under anaerobic conditions for energy conservation inS. oneidensis. IMPORTANCE Shewanella species have garnered interest in biotechnology applications for their ability to respire extracellular terminal electron acceptors, such as insoluble iron oxides and electrodes. While much effort has gone into studying the proteins for extracellular electron transport, how electrons generated through the oxidation of organic carbon sources enter this pathway remains understudied. Here, we quantify the role of formate oxidation in the anaerobic physiology of Shewanella oneidensis Formate oxidation contributes to both the growth rate and yield on a variety of carbon sources through the generation of proton motive force. Advances in our understanding of the anaerobic metabolism of S. oneidensis are important for our ability to utilize and engineer this organism for applications in bioenergy, biocatalysis, and bioremediation.
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47
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Li N, Pan Y, Zhang N, Wang X, Zhou W. The bio-reduction of chromate with periplasmic reductase using a novel isolated strain Pseudoalteromonas sp. CF10-13. RSC Adv 2016. [DOI: 10.1039/c6ra16320c] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
A novel isolated bacteriumPseudoalteromonassp. CF10-13 could reduce Cr(vi) to Cr(iii) by periplasic reductase with Cr(iii) bound to functional groups in extracellular polymeric substance (EPS) or leached to media as soulbe organic-Cr(iii).
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Affiliation(s)
- Na Li
- School of Environmental Science and Engineering
- Shandong University
- Jinan 250100
- China
| | - Yanzhuo Pan
- Jinan Licheng No. 2 High School
- Jinan 250104
- China
| | - Na Zhang
- School of Environmental Science and Engineering
- Shandong University
- Jinan 250100
- China
| | - Xueyan Wang
- School of Environmental Science and Engineering
- Shandong University
- Jinan 250100
- China
| | - Weizhi Zhou
- School of Environmental Science and Engineering
- Shandong University
- Jinan 250100
- China
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48
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Pereira NS, Voegelin AR, Paulukat C, Sial AN, Ferreira VP, Frei R. Chromium-isotope signatures in scleractinian corals from the Rocas Atoll, Tropical South Atlantic. GEOBIOLOGY 2016; 14:54-67. [PMID: 26331762 DOI: 10.1111/gbi.12155] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Accepted: 07/28/2015] [Indexed: 06/05/2023]
Abstract
Chromium-isotope compositions (expressed as δ(53) Cr) of recent and ancient skeletal and non-skeletal carbonates are currently explored as a (paleo-) redox-proxy for shallow seawater. The idea behind this approach is that biogenic and non-biogenic carbonates could potentially be used as archives recording the Cr-isotope composition of seawater in which they formed, and with this contribute to the reconstruction of past paleo-environmental changes in the marine realm, and potentially to climate changes on land. However, investigations addressing the behavior and uptake mechanism of Cr, and the potential isotope fractionations between seawater and biogenic carbonates are scarce. Here, we present a study of Cr-isotope variations in three species of corals and contemporary seawater from the Rocas Atoll, NE, Brazil. Cr-isotope values of the studied coral species (Siderastrea stellata, Porites sp., and Montastrea cavernosa) vary from -0.5 to +0.33‰ and point to significant isotopic disequilibrium with coexisting seawater characterized by a Cr-isotope value of +0.92 ± 0.2‰. This isotopic offset requires reduction of hexavalent Cr(VI) in the sequestration process of all the studied coral species. Cr-isotope values in a profile across an S. stellata colony returned homogeneous, slightly positively fractioned δ(53) Cr values of +0.07 ± 0.08‰ (n = 8, 2σ), which we interpret to reflect a constant reductive uptake during the 20-year growth period recorded in this coral. In contrast, samples across a 12-year growth profile from Porites sp. display rather heterogeneous Cr-isotope values with δ(53) Cr varying from -0.50 to +0.10‰, indicating Cr incorporation under changing redox processes during its growth intervals. We propose a mechanism whereby initial photoreduction of isotopically heavy Cr(VI) to isotopically lighter Cr(III) in the endodermal layer of corals must be followed by efficient and effective re-oxidation of reduced Cr species to favor subsequent chromate (CrO42-) substitution during the calcifying processes ultimately leading to the formation of the coral skeleton.
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Affiliation(s)
- N S Pereira
- NEG-LABISE, Federal University of Pernambuco, Recife, Brazil
- State University of Bahia, Paulo Afonso, Brazil
| | - A R Voegelin
- Department of Geosciences and Natural Resource Management, Nordic Center for Earth Evolution (NordCEE), University of Copenhagen, Copenhagen, Denmark
| | - C Paulukat
- Department of Geosciences and Natural Resource Management, Nordic Center for Earth Evolution (NordCEE), University of Copenhagen, Copenhagen, Denmark
| | - A N Sial
- NEG-LABISE, Federal University of Pernambuco, Recife, Brazil
| | - V P Ferreira
- NEG-LABISE, Federal University of Pernambuco, Recife, Brazil
| | - R Frei
- Department of Geosciences and Natural Resource Management, Nordic Center for Earth Evolution (NordCEE), University of Copenhagen, Copenhagen, Denmark
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49
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Bhattacharya P, Barnebey A, Zemla M, Goodwin L, Auer M, Yannone SM. Complete genome sequence of the chromate-reducing bacterium Thermoanaerobacter thermohydrosulfuricus strain BSB-33. Stand Genomic Sci 2015; 10:74. [PMID: 26445627 PMCID: PMC4595116 DOI: 10.1186/s40793-015-0028-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2014] [Accepted: 05/29/2015] [Indexed: 11/10/2022] Open
Abstract
Thermoanaerobacter thermohydrosulfuricus BSB-33 is a thermophilic gram positive obligate anaerobe isolated from a hot spring in West Bengal, India. Unlike other T. thermohydrosulfuricus strains, BSB-33 is able to anaerobically reduce Fe(III) and Cr(VI) optimally at 60 °C. BSB-33 is the first Cr(VI) reducing T. thermohydrosulfuricus genome sequenced and of particular interest for bioremediation of environmental chromium contaminations. Here we discuss features of T. thermohydrosulfuricus BSB-33 and the unique genetic elements that may account for the peculiar metal reducing properties of this organism. The T. thermohydrosulfuricus BSB-33 genome comprises 2597606 bp encoding 2581 protein genes, 12 rRNA, 193 pseudogenes and has a G + C content of 34.20 %. Putative chromate reductases were identified by comparative analyses with other Thermoanaerobacter and chromate-reducing bacteria.
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Affiliation(s)
- Pamela Bhattacharya
- Life Sciences Division, Lawrence Berkeley National Laboratory, Building 84, Mail Stop 84-171, 1 Cyclotron Road, Berkeley, CA 94720 USA
| | - Adam Barnebey
- Life Sciences Division, Lawrence Berkeley National Laboratory, Building 84, Mail Stop 84-171, 1 Cyclotron Road, Berkeley, CA 94720 USA
| | - Marcin Zemla
- Life Sciences Division, Lawrence Berkeley National Laboratory, Building 84, Mail Stop 84-171, 1 Cyclotron Road, Berkeley, CA 94720 USA
| | - Lynne Goodwin
- Bioscience Division, Los Alamos National Laboratory, Los Alamos, NM USA
| | - Manfred Auer
- Life Sciences Division, Lawrence Berkeley National Laboratory, Building 84, Mail Stop 84-171, 1 Cyclotron Road, Berkeley, CA 94720 USA
| | - Steven M Yannone
- Life Sciences Division, Lawrence Berkeley National Laboratory, Building 84, Mail Stop 84-171, 1 Cyclotron Road, Berkeley, CA 94720 USA
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50
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Ontañon OM, González PS, Agostini E. Biochemical and molecular mechanisms involved in simultaneous phenol and Cr(VI) removal by Acinetobacter guillouiae SFC 500-1A. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2015; 22:13014-13023. [PMID: 25916475 DOI: 10.1007/s11356-015-4571-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Accepted: 04/19/2015] [Indexed: 06/04/2023]
Abstract
Bioremediation has emerged as an environmental friendly strategy to deal with environmental pollution. Since the majority of polluted sites contain complex mixtures of inorganic and organic pollutants, it is important to find bacterial strains that can cope with multiple contaminants. In this work, a bacterial strain isolated from tannery sediments was identified as Acinetobacter guillouiae SFC 500-1A. This strain was able to simultaneously remove high phenol and Cr(VI) concentrations, and the mechanisms involved in such process were evaluated. The phenol biodegradation was catalized by a phenol-induced catechol 1,2-dioxygenase through an ortho-cleavage pathway. Also, NADH-dependent chromate reductase activity was measured in the cytosolic fraction. The ability of this strain to reduce Cr(VI) to Cr(III) was corroborated by detection of Cr(III) in cellular biomass after the removal process. While phenol did not affect significantly the chromate reductase activity, Cr(VI) was a major disruptor of catechol dioxygenase activity. Nevertheless, this activity was high even in presence of high Cr(VI) concentrations. Our results suggest the potential application of A. guillouiae SFC 500-1A for wastewaters treatment, and the obtained data provide the insights into the removal mechanisms, dynamics, and possible limitations of the bioremediation.
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Affiliation(s)
- Ornella M Ontañon
- Departamento de Biología Molecular, FCEFQyN, Universidad Nacional de Río Cuarto, Ruta 36 Km 601. CP 5800, Río Cuarto, Córdoba, Argentina,
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