1
|
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.
Collapse
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.
| |
Collapse
|
2
|
Long M, Zhou C, Zheng X, Rittmann BE. Reduction of Chromate via Biotic and Abiotic Pathways in the Presence of Three Co-contaminating Electron Acceptors. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:21190-21199. [PMID: 38051765 DOI: 10.1021/acs.est.3c04812] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/07/2023]
Abstract
Bioreduction of Cr(VI) to Cr(III) is a promising technology for removing Cr(VI), but Cr(VI) reduction alone cannot support microbial growth. This study investigated the reduction of Cr(VI) in the presence of three electron acceptors that typically coexist with Cr(VI): NO3-, SO42-, and Fe(III). All three systems could reduce Cr(VI) to Cr(III), but the fate of Cr, its impacts on reduction of the other acceptors, and its impact on the microbial community differed. Although Cr(VI) was continuously removed in the NO3--reduction systems, batch tests showed that denitrification was inhibited primarily through impeding nitrite reduction. The SO42- and Fe(III) reduction systems reduced Cr(VI) using a combination of biotic and abiotic processes. Across all three systems, the abundance of genera capable of reducing Cr(VI) increased following the introduction of Cr(VI). Conversely, the abundance of genera that cannot reduce or resist Cr(VI) decreased, leading to restructuring of the microbial community. Furthermore, the abundance of sulfide oxidizers and Fe(II) oxidizers substantially increased after the introduction of chromate. This study provides fundamental knowledge about how Cr(VI) bioreduction interacts with bioreductions of three other co-contaminating electron acceptors.
Collapse
Affiliation(s)
- Min Long
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
- Biodesign Swette Center for Environmental Biotechnology, Arizona State University, Tempe, Arizona 85287, United States
| | - Chen Zhou
- Biodesign Swette Center for Environmental Biotechnology, Arizona State University, Tempe, Arizona 85287, United States
| | - Xiong Zheng
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Bruce E Rittmann
- Biodesign Swette Center for Environmental Biotechnology, Arizona State University, Tempe, Arizona 85287, United States
- School of Sustainable Engineering and the Built Environment, Arizona State University, Tempe, Arizona 85287, United States
| |
Collapse
|
3
|
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.
Collapse
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.
| |
Collapse
|
4
|
Liu J, Sun S, Zhang H, Kong Q, Li Q, Yao X. Remediation materials for the immobilization of hexavalent chromium in contaminated soil: Preparation, applications, and mechanisms. ENVIRONMENTAL RESEARCH 2023; 237:116918. [PMID: 37611786 DOI: 10.1016/j.envres.2023.116918] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Revised: 07/01/2023] [Accepted: 08/16/2023] [Indexed: 08/25/2023]
Abstract
Hexavalent chromium is a toxic metal that can induce severe chromium contamination of soil, posing a potential risk to human health and ecosystems. In recent years, the immobilization of Cr(VI) using remediation materials including inorganic materials, organic materials, microbial agents, and composites has exhibited great potential in remediating Cr(VI)-contaminated soil owing to the environmental-friendliness, short period, simple operation, low cost, applicability on an industrial scale, and high efficiency of these materials. Therefore, a systematical summary of the current progress on various remediation materials is essential. This work introduces the production (sources) of remediation materials and examines their characteristics in detail. Additionally, a critical summary of recent research on the utilization of remediation materials for the stabilization of Cr(VI) in the soil is provided, together with an evaluation of their remediation efficiencies toward Cr(VI). The influences of remediation material applications on soil physicochemical properties, microbial community structure, and plant growth are summarized. The immobilization mechanisms of remediation materials toward Cr(VI) in the soil are illuminated. Importantly, this study evaluates the feasibility of each remediation material application for Cr(VI) remediation. The latest knowledge on the development of remediation materials for the immobilization of Cr(VI) in the soil is also presented. Overall, this review will provide a reference for the development of remediation materials and their application in remediating Cr(VI)-contaminated soil.
Collapse
Affiliation(s)
- Jiwei Liu
- College of Geography and Environment, Shandong Normal University, Jinan, Shandong, 250014, China.
| | - Shuyu Sun
- College of Geography and Environment, Shandong Normal University, Jinan, Shandong, 250014, China
| | - Huanxin Zhang
- College of Geography and Environment, Shandong Normal University, Jinan, Shandong, 250014, China
| | - Qiang Kong
- College of Geography and Environment, Shandong Normal University, Jinan, Shandong, 250014, China; Dongying Institute, Shandong Normal University, Dongying, Shandong, 257092, China
| | - Qian Li
- School of Modern Agriculture and Environment, Weifang Institute of Technology, Weifang, Shandong, 261000, China
| | - Xudong Yao
- Project Department, Shandong Luqiao Detection Technology Co., Ltd., Rizhao, Shandong, 276800, China
| |
Collapse
|
5
|
Hu Z, Zhou Z, Zhou Y, Zheng L, Guo J, Liu Y, Sun Z, Yang Z, Yu X. Synergy of surface adsorption and intracellular accumulation for removal of uranium with Stenotrophomonas sp: Performance and mechanisms. ENVIRONMENTAL RESEARCH 2023; 220:115093. [PMID: 36574801 DOI: 10.1016/j.envres.2022.115093] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2022] [Revised: 12/10/2022] [Accepted: 12/15/2022] [Indexed: 06/17/2023]
Abstract
Uranium is well-known to have serious adverse effects on the ecological environment and human health. Bioremediation stands out among many remediation methods owing to its being economically feasible and environmentally friendly. This study reported a great promising strategy for eliminating uranium by Stenotrophomonas sp. CICC 23833 in the aquatic environment. The bacterium demonstrated excellent uranium adsorption capacity (qmax = 392.9 mg/g) because of the synergistic effect of surface adsorption and intracellular accumulation. Further analysis revealed that hydroxyl, carboxyl, phosphate groups and proteins of microorganisms were essential in uranium adsorption. Intracellular accumulation was closely related to cellular activity, and the efficiency of uranium processing by the permeabilized bacterial cells was significantly improved. In response to uranium stress, the bacterium was found to release multiple ions in conjunction with uranium adsorption, which facilitates the maintenance of bacterial life activities and the conversion of uranyl to precipitates. These above results indicated that Stenotrophomonas sp. Had great potential application value for the remediation of uranium.
Collapse
Affiliation(s)
- Zhongqiang Hu
- State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, Jiangxi, China; School of Water Resources and Environmental Engineering, East China University of Technology, Nanchang 330013, Jiangxi, China
| | - Zhongkui Zhou
- State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, Jiangxi, China; School of Water Resources and Environmental Engineering, East China University of Technology, Nanchang 330013, Jiangxi, China.
| | - Yaoyu Zhou
- State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, Jiangxi, China; School of Water Resources and Environmental Engineering, East China University of Technology, Nanchang 330013, Jiangxi, China; College of Resources and Environment, Hunan Agricultural University, Changsha 410128, China.
| | - Lili Zheng
- School of Energy and Environmental Engineering, University of Science and Technology Beijing, Beijing, 100083, China
| | - Jianping Guo
- State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, Jiangxi, China; School of Water Resources and Environmental Engineering, East China University of Technology, Nanchang 330013, Jiangxi, China
| | - Yong Liu
- State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, Jiangxi, China; School of Water Resources and Environmental Engineering, East China University of Technology, Nanchang 330013, Jiangxi, China
| | - Zhanxue Sun
- State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, Jiangxi, China; School of Water Resources and Environmental Engineering, East China University of Technology, Nanchang 330013, Jiangxi, China
| | - Zhihui Yang
- School of Metallurgy and Environment, Central South University, Changsha 410083, Hunan, China
| | - Xiaoxia Yu
- State Key Laboratory of Nuclear Resources and Environment, East China University of Technology, Nanchang 330013, Jiangxi, China; School of Water Resources and Environmental Engineering, East China University of Technology, Nanchang 330013, Jiangxi, China
| |
Collapse
|
6
|
Bao Z, Feng H, Tu W, Li L, Li Q. Method and mechanism of chromium removal from soil: a systematic review. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:35501-35517. [PMID: 35226261 DOI: 10.1007/s11356-022-19452-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/03/2021] [Accepted: 02/23/2022] [Indexed: 06/14/2023]
Abstract
Heavy metal pollution has increasingly affected human life, and the treatment of heavy metal pollution, especially chromium pollution, is still a major problem in the field of environmental governance. As a commonly used industrial metal, chromium can easily enter the environment with improperly treated industrial waste or wastewater, then pollute soil and water sources, and eventually accumulate in the human body through the food chain. Many countries and regions in the world are threatened by soil chromium pollution, resulting in the occurrence of cancer and a variety of metabolic diseases. However, as a serious threat to agriculture, food, and human health. Notwithstanding, there are limited latest and systematic review on the removal methods, mechanisms, and effects of soil chromium pollution in recent years. Hence, this article outlines some of the methods and mechanisms for the removal of chromium in soil, including physical, chemical, biological, and biochar methods, which provide a reference for the treatment and research on soil chromium pollution drawn from existing publications.
Collapse
Affiliation(s)
- Zhijie Bao
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Sichuan Engineering & Technology Research Center of Coarse Cereal Industralization, School of Food and Biological Engineering, Chengdu University, Chengdu, Sichuan, China
| | - Huiyu Feng
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Sichuan Engineering & Technology Research Center of Coarse Cereal Industralization, School of Food and Biological Engineering, Chengdu University, Chengdu, Sichuan, China
| | - Wenying Tu
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Sichuan Engineering & Technology Research Center of Coarse Cereal Industralization, School of Food and Biological Engineering, Chengdu University, Chengdu, Sichuan, China
| | - Lijiao Li
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Sichuan Engineering & Technology Research Center of Coarse Cereal Industralization, School of Food and Biological Engineering, Chengdu University, Chengdu, Sichuan, China
| | - Qiang Li
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture and Rural Affairs, Sichuan Engineering & Technology Research Center of Coarse Cereal Industralization, School of Food and Biological Engineering, Chengdu University, Chengdu, Sichuan, China.
| |
Collapse
|
7
|
Modeling cometabolism of hexavalent chromium by iron reducing bacteria in tertiary substrate system. Sci Rep 2021; 11:10864. [PMID: 34035332 PMCID: PMC8149721 DOI: 10.1038/s41598-021-90137-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2021] [Accepted: 03/31/2021] [Indexed: 11/08/2022] Open
Abstract
In this study, a bacterial strain Serratia sp. was employed for the reduction of synthetically prepared different concentration of Cr(VI) solution (10, 25, 40, 50 and 100 mg/L). Cometabolism study have been carried out in the binary substrate system as well as in the tertiary substrate system. The results revealed that when glucose was added as a co-substrate, at low Cr(VI) concentration, complete reduction was achieved followed by increased biomass growth, but when Cr(VI) concentration was increased to 100 mg/L, the reduction decline to 93%. But in presence of high carbon iron filings (HCIF) as co-substrate even at higher Cr(VI) concentration i.e. 100 mg/L, 100% reduction was achieved and the cell growth continued till 124 h. The study was illustrated via Monod growth kinetic model for tertiary substrate system and the kinetic parameters revealed that the HCIF and glucose combination showed least inhibition to hexavalent chromium reduction by Serratia sp.
Collapse
|
8
|
Rahman Z, Thomas L. Chemical-Assisted Microbially Mediated Chromium (Cr) (VI) Reduction Under the Influence of Various Electron Donors, Redox Mediators, and Other Additives: An Outlook on Enhanced Cr(VI) Removal. Front Microbiol 2021; 11:619766. [PMID: 33584585 PMCID: PMC7875889 DOI: 10.3389/fmicb.2020.619766] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2020] [Accepted: 12/16/2020] [Indexed: 12/13/2022] Open
Abstract
Chromium (Cr) (VI) is a well-known toxin to all types of biological organisms. Over the past few decades, many investigators have employed numerous bioprocesses to neutralize the toxic effects of Cr(VI). One of the main process for its treatment is bioreduction into Cr(III). Key to this process is the ability of microbial enzymes, which facilitate the transfer of electrons into the high valence state of the metal that acts as an electron acceptor. Many underlying previous efforts have stressed on the use of different external organic and inorganic substances as electron donors to promote Cr(VI) reduction process by different microorganisms. The use of various redox mediators enabled electron transport facility for extracellular Cr(VI) reduction and accelerated the reaction. Also, many chemicals have employed diverse roles to improve the Cr(VI) reduction process in different microorganisms. The application of aforementioned materials at the contaminated systems has offered a variety of influence on Cr(VI) bioremediation by altering microbial community structures and functions and redox environment. The collective insights suggest that the knowledge of appropriate implementation of suitable nutrients can strongly inspire the Cr(VI) reduction rate and efficiency. However, a comprehensive information on such substances and their roles and biochemical pathways in different microorganisms remains elusive. In this regard, our review sheds light on the contributions of various chemicals as electron donors, redox mediators, cofactors, etc., on microbial Cr(VI) reduction for enhanced treatment practices.
Collapse
Affiliation(s)
- Zeeshanur Rahman
- Department of Botany, Zakir Husain Delhi College, University of Delhi, Delhi, India
| | - Lebin Thomas
- Department of Botany, Hansraj College, University of Delhi, Delhi, India
| |
Collapse
|
9
|
Zhu Y, Yan J, Xia L, Zhang X, Luo L. Mechanisms of Cr(VI) reduction by Bacillus sp. CRB-1, a novel Cr(VI)-reducing bacterium isolated from tannery activated sludge. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2019; 186:109792. [PMID: 31629191 DOI: 10.1016/j.ecoenv.2019.109792] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2019] [Revised: 10/07/2019] [Accepted: 10/10/2019] [Indexed: 06/10/2023]
Abstract
Cr(VI) reduction by microorganisms has been extensively reported, however, the mechanism of Cr(VI) reduction varies among different microorganisms. In this study, a Cr(VI)-reducing bacterium identified as Bacillus sp. was isolated from tannery activated sludge, strain CRB-1 was able to completely reduce 50 mg/L of Cr(VI) within 24 h under aerobic conditions and exhibited considerable Cr(VI) removal efficiency in the pH range from 7.0 to 9.0, temperature 24-42 °C. Cr(VI) reduction assays with resting cells, permeabilized cells, and subcellular fractions suggested that Cr(VI) reduction mainly occurred in the cytoplasm. According to qRT-PCR analysis, a chrA gene and a nitR2 gene were up-regulated under Cr(VI) stress. Heterologous expression of the chrA gene and the nitR2 gene indicated that ChrA was associated with Cr(VI) resistance, while NitR2 was responsible for Cr(VI) reduction. Furthermore, soluble end products were detected. On the basis of FTIR, it was speculated that the formation of soluble end products may be due to the complexation of EPS with Cr(III). Consequently, the Cr(VI)-reducing ability of strain CRB-1 and its chromate reductases enables CRB-1 a potential candidate for Cr(VI) bioremediation.
Collapse
Affiliation(s)
- Yunfei Zhu
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, 510006, China
| | - Junwei Yan
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, 510006, China
| | - Li Xia
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, 510006, China
| | - Xiang Zhang
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, 510006, China
| | - Lixin Luo
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, 510006, China.
| |
Collapse
|
10
|
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.
Collapse
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
| |
Collapse
|
11
|
Kumar M, Saini HS. Reduction of hexavalent chromium (VI) by indigenous alkaliphilic and halotolerant Microbacterium sp. M5: comparative studies under growth and nongrowth conditions. J Appl Microbiol 2019; 127:1057-1068. [PMID: 31260173 DOI: 10.1111/jam.14366] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2019] [Revised: 05/29/2019] [Accepted: 06/24/2019] [Indexed: 01/26/2023]
Abstract
AIMS To evaluate hexavalent chromium (Cr (VI)) reduction potential of indigenous isolate M5, under growing and nongrowing conditions. METHODS AND RESULTS Microbacterium sp. M5 was isolated from soil samples collected from a common effluent treatment plant, after enrichment of indigenous microbial diversity in the presence of 200 mg l-1 of Cr (VI). The isolate achieved complete reduction of 400 mg l-1 Cr (VI) supplement to Luria Bertani medium having initial pH of 9·0 after 48 h incubation. Furthermore, the reduction potential of resting and surfactant treated cell membrane compromised cells of M5 was evaluated. The control and biosurfactant treated cells achieved 22·71 ± 0·5% and 40·56 ± 0·5% reduction of 50 mg l-1 Cr (VI) in Tris-HCl buffer, under resting cells conditions. To the best of our knowledge, this is the first report where cells with compromised cell membrane obtained after exposure to biosurfactant have been evaluated for Cr (VI) reduction. CONCLUSION The Cr (VI) reduction potential of Microbacterium sp. M5 could be effectively exploited for treatment of chromium-rich effluents, under nongrowing conditions. SIGNIFICANCE AND IMPACT OF THE STUDY The isolate M5 could be a potential inoculum for effluent treatment plants as it is able to support Cr (VI) reduction under wide range of pH, salinity and in the presence of different metal ions.
Collapse
Affiliation(s)
- M Kumar
- Department of Microbiology, Guru Nanak Dev University, Amritsar, India
| | - H S Saini
- Department of Microbiology, Guru Nanak Dev University, Amritsar, India
| |
Collapse
|
12
|
Zeng Q, Hu Y, Yang Y, Hu L, Zhong H, He Z. Cell envelop is the key site for Cr(Ⅵ) reduction by Oceanobacillus oncorhynchi W4, a newly isolated Cr(Ⅵ) reducing bacterium. JOURNAL OF HAZARDOUS MATERIALS 2019; 368:149-155. [PMID: 30677647 DOI: 10.1016/j.jhazmat.2019.01.031] [Citation(s) in RCA: 68] [Impact Index Per Article: 13.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2018] [Revised: 01/10/2019] [Accepted: 01/11/2019] [Indexed: 06/09/2023]
Abstract
The Cr(Ⅵ) removal way and Cr(Ⅵ) reducing site of Oceanobacillus oncorhynchi W4, a novel Cr(Ⅵ) reducing bacterium, were investigated in this study. Results showed that about 74.2% of Cr(Ⅵ) was removed from solution by growing cells within 72 h. Moreover, heating-killed resting cells had little Cr(Ⅵ) removal capacity, which was significantly lower than that of resting cells, which reached nearly 80% removal rate, suggesting that the way of Cr(Ⅵ) removal mainly relied on biological reduction rather than biosorption. And the Cr(Ⅵ) reduction was found to be significantly enhanced by some electron donors, especially glycerin, which further verified enzyme-mediated biological reduction as the way for Cr(Ⅵ) removal. Experiments of Cr(Ⅵ) removal by permeable cells indicated that there was no significant difference in chromium reduction between the impermeable cells and the permeable cells. The cell envelop fraction had a Cr(Ⅵ) removal rate of 82.9%, apparently higher than cytoplasmic fraction (11.1%), indicating that the cell envelop was the main location for Cr(Ⅵ) reduction, which were further demonstrated by Scanning Electron Microscope and Transmission electron microscopy plus EDS analysis. Furthermore, analysis of X-ray photoelectron spectroscopy manifested that CO, C-OH and C-OC groups on the surfaces played major roles in correlation with chromium species.
Collapse
Affiliation(s)
- Qiang Zeng
- School of Minerals Processing and Bioengineering, MOE Key Laboratory of Biohydrometallurgy, Central South University, Changsha, 410083, China
| | - Yuting Hu
- School of Minerals Processing and Bioengineering, MOE Key Laboratory of Biohydrometallurgy, Central South University, Changsha, 410083, China
| | - Yiran Yang
- School of Minerals Processing and Bioengineering, MOE Key Laboratory of Biohydrometallurgy, Central South University, Changsha, 410083, China
| | - Liang Hu
- School of Minerals Processing and Bioengineering, MOE Key Laboratory of Biohydrometallurgy, Central South University, Changsha, 410083, China
| | - Hui Zhong
- School of Life Sciences, Central South University, Changsha, 410083, China.
| | - Zhiguo He
- School of Minerals Processing and Bioengineering, MOE Key Laboratory of Biohydrometallurgy, Central South University, Changsha, 410083, China.
| |
Collapse
|
13
|
Elahi A, Rehman A. Comparative behavior of two gram positive Cr 6+ resistant bacterial strains Bacillus aerius S1 and Brevibacterium iodinum S2 under hexavalent chromium stress. BIOTECHNOLOGY REPORTS (AMSTERDAM, NETHERLANDS) 2019; 21:e00307. [PMID: 30705835 PMCID: PMC6348243 DOI: 10.1016/j.btre.2019.e00307] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 01/06/2019] [Accepted: 01/14/2019] [Indexed: 01/27/2023]
Abstract
Bacillus aerius S1 and Brevibacterium iodinum S2 showed maximum growth at 37 °C and pH 8. B. aerius and B. iodinum could resist Cr6+ upto 30 and 35 mM and biosorption proficiency (q) of B. aerius S1 was 19, 27, 52 and 34 mM/g while for B. iodinum S2, it was 39, 50, 23 and 16 mM/g mM/g after 2, 4, 6 and 8 days of incubation. A pronounced rise in antioxidant enzymes activities was determined in B. aerius S1 i.e. POX (963%), CAT (717%), APOX (699%), SOD (683%), and GST (792%). However, in B. iodinum S2, relatively a minor increase was estimated. A significant GSH increase was determined in B. aerius S1 (364%) and B. iodinum S2 (663%) cultures under 2 mM Cr6+ stress. Pilot scale study demonstrated that both strains could reduce Cr6+ into Cr3+ within 6 days from the original tannery effluent with efficiency of 99%.
Collapse
Affiliation(s)
| | - Abdul Rehman
- Department of Microbiology and Molecular Genetics, University of the Punjab, New Campus, Lahore 54590, Pakistan
| |
Collapse
|
14
|
Recognition of a New Cr(VI)-Reducing Strain and Study of the Potential Capacity for Reduction of Cr(VI) of the Strain. BIOMED RESEARCH INTERNATIONAL 2019; 2019:5135017. [PMID: 30881989 PMCID: PMC6387719 DOI: 10.1155/2019/5135017] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/26/2018] [Revised: 11/14/2018] [Accepted: 01/22/2019] [Indexed: 12/14/2022]
Abstract
The biotransformation of hexavalent chromium [Cr(VI)] via Cr(VI)-reducing microorganisms is considered an ecofriendly approach to detoxify Cr(VI). A new Cr(VI)-reducing bacterium named Microbacterium sp. QH-2 was isolated in this study. Scanning electron microscopy (SEM) images showed protrusions on the bacterial surface of strain QH-2 after an 18 h incubation in media under 10 mM Cr(VI) treatment. Results of the experiments on the capacity of reducing Cr(VI) indicated that strain QH-2 could reduce 100% Cr(VI) less than 48-96 h. When media with 4 mM Cr(VI) were incubated, the fastest reduction rate of strain QH-2 could come up to 2.17 mg/L Cr(VI) h−1. Furthermore, strain QH-2 could reduce Cr(VI) over the pH between 7 and 10. The optimum pH to reduce Cr(VI) by strain QH-2 was 9. Strain QH-2 also exhibited a relatively high tolerance even to 20 mM Cr(VI). These results declared that strain QH-2 had the potential to detoxify Cr(VI) in the Cr(VI)-contaminated soil or effluent.
Collapse
|
15
|
Revelo Romo DM, Hurtado Gutiérrez NH, Ruiz Pazos JO, Pabón Figueroa LV, Ordóñez Ordóñez LA. Bacterial diversity in the Cr(VI) reducing biocathode of a Microbial Fuel Cell with salt bridge. Rev Argent Microbiol 2018; 51:110-118. [PMID: 30144991 DOI: 10.1016/j.ram.2018.04.005] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 02/16/2018] [Accepted: 04/07/2018] [Indexed: 02/04/2023] Open
Abstract
Although Cr(VI)-reducing and/or tolerant microorganisms have been investigated, there is no detailed information on the composition of the microbial community of the biocathode microbial fuel cell for Cr(VI) reduction. In this investigation, the bacterial diversity of a biocathode was analyzed using 454 pyrosequencing of the 16S rRNA gene. It was found that most bacteria belonged to phylum Proteobacteria (78.8%), Firmicutes (7.9%), Actinobacteria (6.6%) and Bacteroidetes (5.5%), commonly present in environments contaminated with Cr(VI). The dominance of the genus Pseudomonas (34.87%), followed by the genera Stenotrophomonas (5.8%), Shinella (4%), Papillibacter (3.96%), Brevundimonas (3.91%), Pseudochrobactrum (3.54%), Ochrobactrum (3.49%), Hydrogenophaga (2.88%), Rhodococcus (2.88%), Fluviicola (2.35%), and Alcaligenes (2.3%), was found. It is emphasized that some genera have not previously been associated with Cr(VI) reduction. This biocathode from waters contaminated with tannery effluents was able to remove Cr(VI) (97.83%) in the cathodic chamber. Additionally, through use of anaerobic sludge in the anodic chamber, the removal of 76.6% of organic matter (glucose) from synthetic waste water was achieved. In this study, an efficient biocathode for the reduction of Cr(VI) with future use in bioremediation, was characterized.
Collapse
Affiliation(s)
- Dolly Margot Revelo Romo
- Biology Department, Universidad de Nariño, Calle 18 Carrera 50, Campus Torobajo, San Juan de Pasto, Nariño, Colombia.
| | | | - Jaime Orlando Ruiz Pazos
- Electrical Engineering Department, Universidad de Nariño, Calle 18 Carrera 50, Campus Torobajo, San Juan de Pasto, Nariño, Colombia
| | - Lizeth Vanessa Pabón Figueroa
- Biology Department, Universidad de Nariño, Calle 18 Carrera 50, Campus Torobajo, San Juan de Pasto, Nariño, Colombia
| | | |
Collapse
|
16
|
Bioinformatics Analysis and Characterization of Highly Efficient Polyvinyl Alcohol (PVA)-Degrading Enzymes from the Novel PVA Degrader Stenotrophomonas rhizophila QL-P4. Appl Environ Microbiol 2017; 84:AEM.01898-17. [PMID: 29079625 DOI: 10.1128/aem.01898-17] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Accepted: 10/23/2017] [Indexed: 01/24/2023] Open
Abstract
Polyvinyl alcohol (PVA) is used widely in industry, and associated environmental pollution is a serious problem. Herein, we report a novel, efficient PVA degrader, Stenotrophomonas rhizophila QL-P4, isolated from fallen leaves from a virgin forest in the Qinling Mountains. The complete genome was obtained using single-molecule real-time (SMRT) technology and corrected using Illumina sequencing. Bioinformatics analysis revealed eight PVA/vinyl alcohol oligomer (OVA)-degrading genes. Of these, seven genes were predicted to be involved in the classic intracellular PVA/OVA degradation pathway, and one (BAY15_3292) was identified as a novel PVA oxidase. Five PVA/OVA-degrading enzymes were purified and characterized. One of these, BAY15_1712, a PVA dehydrogenase (PVADH), displayed high catalytic efficiency toward PVA and OVA substrate. All reported PVADHs only have PVA-degrading ability. Most importantly, we discovered a novel PVA oxidase (BAY15_3292) that exhibited higher PVA-degrading efficiency than the reported PVADHs. Further investigation indicated that BAY15_3292 plays a crucial role in PVA degradation in S. rhizophila QL-P4. Knocking out BAY15_3292 resulted in a significant decline in PVA-degrading activity in S. rhizophila QL-P4. Interestingly, we found that BAY15_3292 possesses exocrine activity, which distinguishes it from classic PVADHs. Transparent circle experiments further proved that BAY15_3292 greatly affects extracellular PVA degradation in S. rhizophila QL-P4. The exocrine characteristics of BAY15_3292 facilitate its potential application to PVA bioremediation. In addition, we report three new efficient secondary alcohol dehydrogenases (SADHs) with OVA-degrading ability in S. rhizophila QL-P4; in contrast, only one OVA-degrading SADH was reported previously.IMPORTANCE With the widespread application of PVA in industry, PVA-related environmental pollution is an increasingly serious issue. Because PVA is difficult to degrade, it accumulates in aquatic environments and causes chronic toxicity to aquatic organisms. Biodegradation of PVA, as an economical and environment-friendly method, has attracted much interest. To date, effective and applicable PVA-degrading bacteria/enzymes have not been reported. Herein, we report a new efficient PVA degrader (S. rhizophila QL-P4) that has five PVA/OVA-degrading enzymes with high catalytic efficiency, among which BAY15_1712 is the only reported PVADH with both PVA- and OVA-degrading abilities. Importantly, we discovered a novel PVA oxidase (BAY15_3292) that is not only more efficient than other reported PVA-degrading PVADHs but also has exocrine activity. Overall, our findings provide new insight into PVA-degrading pathways in microorganisms and suggest S. rhizophila QL-P4 and its enzymes have the potential for application to PVA bioremediation to reduce or eliminate PVA-related environmental pollution.
Collapse
|
17
|
Copper (II) binding of NAD(P)H- flavin oxidoreductase (NfoR) enhances its Cr (VI)-reducing ability. Sci Rep 2017; 7:15481. [PMID: 29133854 PMCID: PMC5684319 DOI: 10.1038/s41598-017-15588-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2017] [Accepted: 10/23/2017] [Indexed: 12/16/2022] Open
Abstract
Microbes can reduce hexavalent chromium Cr (VI) to the less toxic and soluble trivalent Cr (III). Copper stimulates microbial reduction of Cr (VI) by the Bacillus, Ochrobactrum, and Gluconobacter species; however, the mechanism remains unclear. In our study, the rate of Cr (VI) reduction by Staphylococcus aureus LZ-01 was increased by 210 % when supplemented with 60 μM Cu (II). A putative NAD(P)H-flavin oxidoreductase gene (nfoR) was upregulated under Cr (VI) stress. NfoR-knockout mutant displayed impaired reduction of Cr (VI) and Cu (II)-enhanced Cr (VI) reduction by nfoR isogenic mutant was attenuated in the presence of Cu (II). In vitro tests showed an increased Vmax value of 25.22 μM min−1 mg−1 NfoR in the presence of Cu (II). Together, these results indicate that NfoR is responsible for Cu (II) enhancement. Isothermal titration calorimetry (ITC) assays confirmed the interaction of NfoR with Cu (II) at the dissociation constant of 85.5 μM. Site-directed mutagenesis indicates that His100, His128, and Met165 residues may be important for Cu (II) binding, while Cys163 is necessary for the FMN binding of NfoR. These findings show that Cu (II)-enhanced NfoR belongs to a new branch of Cr (VI) reductases and profoundly influences Cr (VI) reduction.
Collapse
|
18
|
Karthik C, Barathi S, Pugazhendhi A, Ramkumar VS, Thi NBD, Arulselvi PI. Evaluation of Cr(VI) reduction mechanism and removal by Cellulosimicrobium funkei strain AR8, a novel haloalkaliphilic bacterium. JOURNAL OF HAZARDOUS MATERIALS 2017; 333:42-53. [PMID: 28340388 DOI: 10.1016/j.jhazmat.2017.03.037] [Citation(s) in RCA: 110] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2017] [Revised: 03/01/2017] [Accepted: 03/16/2017] [Indexed: 05/10/2023]
Abstract
The present study, a novel haloalkaliphilic Cr(VI) tolerant bacterial strain, Cellulosimicrobium funkei AR8, was isolated and characterized for its high Cr(VI) reduction. In batch experiments, Cr(VI) reduction was evaluated under different parametric conditions which include different pH (5-9), temperature (25-45°C), NaCl (0-3%) and Cr(VI) concentrations (100-250μg/ml). Variations in the cell surface functional groups and morphology of the bacterial cells after Cr(VI) reduction were characterized by FT-IR and SEM-EDX. FT-IR analysis revealed that cell surface functional groups such as alkanes, amide and amines are involved in chromium biosorption and SEM-EDX results showed that biosorption and immobilization of chromium species on the cell surface. Bioconversion of Cr(VI) into Cr(III) by strain AR8 was confirmed by XRD and Raman spectroscopy analysis. Intracellular localization of reduced product (Cr(III)) was visualized by TEM analysis. Various instrumentation analysis verified that Cr(VI) removal mechanism of C. funkei AR8 strain was achieved by both extra and intracellular reducing machinery. Toxicity study revealed that the bacterially reduced product exerted less toxic effects on phenotypic, survival (91.31%), hatching (84.04%) and heart function (115±1.03 beats/min) of zebrafish (Danio rerio) embryos. Higher Cr(VI) reducing ability of the strain under haloalkaliphilic condition suggests the C. funkei AR8 as a novel and efficient strain for remediating Cr(VI) contaminated industrial effluents with high salinity and alkalinity.
Collapse
Affiliation(s)
- Chinnannan Karthik
- Plant and Microbial Biotechnology Laboratory, Department of Biotechnology, School of Biosciences, Periyar University, Salem, 636 011, Tamil Nadu, India
| | - Selvaraj Barathi
- Plant and Microbial Biotechnology Laboratory, Department of Biotechnology, School of Biosciences, Periyar University, Salem, 636 011, Tamil Nadu, India
| | - Arivalagan Pugazhendhi
- Department of Environmental Biotechnology, School of Environmental Sciences, Bharathidasan University, Tamil Nadu, India; Deparment of Environmental Engineering, Daegu University, Gyeongbuk 38453, Republic of Korea
| | - Vijayan Sri Ramkumar
- Department of Environmental Biotechnology, School of Environmental Sciences, Bharathidasan University, Tamil Nadu, India
| | - Ngoc Bao Dung Thi
- Faculty of Environment and Labour Safety, Ton Duc Thang University, No.19 Nguyen Huu Tho Street, Tan Phong Ward, District 7, Ho Chi Minh City, Viet Nam
| | - Padikasan Indra Arulselvi
- Plant and Microbial Biotechnology Laboratory, Department of Biotechnology, School of Biosciences, Periyar University, Salem, 636 011, Tamil Nadu, India.
| |
Collapse
|
19
|
Li T, Liu T, Zheng C, Kang C, Yang Z, Yao X, Song F, Zhang R, Wang X, Xu N, Zhang C, Li W, Li S. Changes in soil bacterial community structure as a result of incorporation of Brassica plants compared with continuous planting eggplant and chemical disinfection in greenhouses. PLoS One 2017; 12:e0173923. [PMID: 28346463 PMCID: PMC5367839 DOI: 10.1371/journal.pone.0173923] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2016] [Accepted: 02/28/2017] [Indexed: 11/18/2022] Open
Abstract
Greenhouse eggplant monocropping in China has contributed to the aggravation of soil-borne diseases, reductions in crop quality and yield, and the degradation of physical and chemical soil properties. Crop rotation is one effective way of alleviating the problems of continuous cropping worldwide; however, few studies have reported changes in soil bacterial community structures and physical and chemical soil properties after Brassica vegetables had been rotated with eggplant in greenhouses. In this experiment, mustard-eggplant (BFN) and oilseed rape-eggplant (BFC) rotations were studied to identify changes in the physicochemical properties and bacterial community structure in soil that was previously subject to monocropping. Samples were taken after two types of Brassica plants incorporated into soil for 15 days to compare with continually planted eggplant (control, CN) and chemical disinfection of soil (CF) in greenhouses. MiSeq pyrosequencing was used to analyze soil bacterial diversity and structure in the four different treatments. A total of 55,129 reads were identified, and rarefaction analysis showed that the soil treatments were equally sampled. The bacterial richness of the BFC treatment and the diversity of the BFN treatment were significantly higher than those of the other treatments. Further comparison showed that the bacterial community structures of BFC and BFN treatments were also different from CN and CF treatments. The relative abundance of several dominant bacterial genera in the BFC and BFN treatments (such as Flavobacteria, Stenotrophomonas, Massilia and Cellvibrio, which played different roles in improving soil fertility and advancing plant growth) was distinctly higher than the CN or CF treatments. Additionally, the total organic matter and Olsen-P content of the BFC and BFN treatments were significantly greater than the CN treatment. We conclude that Brassica vegetables-eggplant crop rotations could provide a more effective means of solving the problems of greenhouse eggplant monocultures.
Collapse
Affiliation(s)
- Tianzhu Li
- Resource and Environmental College, Northeast Agricultural University, Harbin, China
| | - Tongtong Liu
- Resource and Environmental College, Northeast Agricultural University, Harbin, China
| | - Chengyu Zheng
- Resource and Environmental College, Northeast Agricultural University, Harbin, China
| | - Chunsheng Kang
- Research Development and Evaluation Center of Laboratory, Harbin, China
| | - Zichao Yang
- Resource and Environmental College, Northeast Agricultural University, Harbin, China
| | - Xiaotong Yao
- Resource and Environmental College, Northeast Agricultural University, Harbin, China
| | - Fengbin Song
- Resource and Environmental College, Northeast Agricultural University, Harbin, China
| | - Runzhi Zhang
- Resource and Environmental College, Northeast Agricultural University, Harbin, China
| | - Xuerong Wang
- Resource and Environmental College, Northeast Agricultural University, Harbin, China
| | - Ning Xu
- Resource and Environmental College, Northeast Agricultural University, Harbin, China
| | - Chunyi Zhang
- Resource and Environmental College, Northeast Agricultural University, Harbin, China
| | - Wei Li
- Resource and Environmental College, Northeast Agricultural University, Harbin, China
| | - Shumin Li
- Resource and Environmental College, Northeast Agricultural University, Harbin, China
| |
Collapse
|
20
|
Russo G, Libkind D, Giraudo MR, Delgado OD. Heavy metal capture by autochthonous yeasts from a volcanic influenced environment of Patagonia. J Basic Microbiol 2016; 56:1203-1211. [PMID: 27427287 DOI: 10.1002/jobm.201600048] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Accepted: 05/20/2016] [Indexed: 11/08/2022]
Abstract
Heavy metals at elevated concentrations are a major threat to agricultural and human health. Typically, human activities tend to release these metals to the environment in aqueous solutions, generating high levels of pollution due to the mobility of the heavy metals. The aim of the present work was to assess heavy metal tolerance in yeasts isolated from Río Agrio - Lake Caviahue volcanic acidic aquatic environment and to evaluate the capacity of selected strains to capture metals in acidic culture media conditions. The ability of three yeast species, Cryptococcus agrionensis, Cryptococcus sp. 2, and Coniochaeta fodinicola, to tolerate and capture metals in live cultures has been evaluated. These three yeast species showed high tolerance to low pH and elevated concentrations of metals, thus implying their autochthonous status. Minimal inhibitory concentration (MIC) for growth obtained for these isolates showed elevated tolerance to the six heavy metals evaluated and were significantly higher than those registered for other microorganisms. C. agrionensis was able to capture 15.80 mg (g biomass)-1 of Cu2+ (MIC: 0.22 g L-1 ), Cryptococcus sp. 2 was able to capture 36.25 and 65.28 mg (g biomass)-1 of Ni2+ and Zn2+ , respectively (MIC: 0.56 and 1.68, respectively), and C. fodinicola was able to capture 67.11 mg (g biomass)-1 of Zn2+ (MIC: 3.75). This work reported the ability of yeasts to capture metals in acidic conditions for the first time. We hope that it represents the step-stone for future researches in the ability and metabolism of yeasts form acidic aquatic environment related to metal tolerance and capture.
Collapse
Affiliation(s)
- Gabriel Russo
- Centro Científico Tecnológico Patagonia Norte (CCT-Patagonia Norte), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), San Carlos de Bariloche, Río Negro, Argentina
| | - Diego Libkind
- Laboratorio de Microbiología Aplicada, Biotecnología y Bioinformática de Levaduras, Instituto Andino-Patagónico de Tecnologías Biológicas y Geoambientales (IPATEC), CONICET - UNComahue (CRUB), Bariloche, Río Negro, Argentina
| | - María Rosa Giraudo
- Laboratorio de Microbiología Aplicada, Biotecnología y Bioinformática de Levaduras, Instituto Andino-Patagónico de Tecnologías Biológicas y Geoambientales (IPATEC), CONICET - UNComahue (CRUB), Bariloche, Río Negro, Argentina
| | - Osvaldo Daniel Delgado
- Centro de Investigación y Transferencia Catamarca (CITCa), Universidad Nacional de Catamarca, CONICET, San Fernando del Valle de Catamarca, Catamarca, Argentina
| |
Collapse
|
21
|
Huang J, Li J, Wang G. Production of a microcapsule agent of chromate-reducing Lysinibacillus fusiformis ZC1 and its application in remediation of chromate-spiked soil. SPRINGERPLUS 2016; 5:561. [PMID: 27218011 PMCID: PMC4856709 DOI: 10.1186/s40064-016-2177-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Accepted: 04/18/2016] [Indexed: 11/10/2022]
Abstract
Lysinibacillus fusiformis ZC1 is an efficient Cr(VI)-reducing bacterium that can transform the toxic and soluble chromate [Cr(VI)] form to the less toxic and precipitated chromite form [Cr(III)]. As such, this strain might be applicable for bioremediation of Cr(VI) in soil by reducing its bioavailability. The study objective was to prepare a microcapsule agent of strain ZC1 for bioremediation of Cr(VI)-contaminated soil. Using a single-factor orthogonal array design, the optimal fermentation medium was obtained and consisted of 6 g/L corn flour, 12 g/L soybean flour, 8 g/L NH4Cl and 6 g/L CaCl2. After enlarged fermentation, the cell and spore densities were 5.9 × 109 and 1.7 × 108 cfu/mL, respectively. The fermentation products were collected and embedded with 1 % gum arabic and 1 % sorbitol as the microcapsule carriers and were subsequently spray-dried. Strain ZC1 exhibited viable cell counts of (3.6 ± 0.44) × 1010 cfu/g dw after 50-day storage at room temperature. In simulated soil bioremediation experiments, 67 % of Cr(VI) was reduced in 5 days with the inoculation of this microcapsule agent, and the Cr(VI) concentration was below the soil Cr(VI) standard level. The results demonstrated that the microcapsule agent of strain ZC1 is efficient for bioremediation of Cr(VI)-contaminated soil.
Collapse
Affiliation(s)
- Jun Huang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070 People's Republic of China
| | - Jingxin Li
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070 People's Republic of China
| | - Gejiao Wang
- State Key Laboratory of Agricultural Microbiology, College of Life Science and Technology, Huazhong Agricultural University, Wuhan, 430070 People's Republic of China
| |
Collapse
|
22
|
Ge S, Ge SC. Simultaneous Cr(VI) reduction and Zn(II) biosorption by Stenotrophomonas sp. and constitutive expression of related genes. Biotechnol Lett 2016; 38:877-84. [DOI: 10.1007/s10529-016-2057-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Accepted: 01/26/2016] [Indexed: 10/22/2022]
|