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Li X, Wang J, Yang Y, Jin H, Wang H, Zhang Z, Li X, Cui Y, Wang X, Yan J. Sequential Reductive Dechlorination of Triclosan by Sediment Microbiota Harboring Organohalide-Respiring Dehalococcoidia. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:14843-14854. [PMID: 39106339 DOI: 10.1021/acs.est.4c04594] [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: 08/09/2024]
Abstract
Aquatic ecosystems represent a prominent reservoir of xenobiotic compounds, including triclosan (TCS), a broad-spectrum biocide extensively used in pharmaceuticals and personal care products. As a biogeochemical hotspot, the potential of aquatic sediments for the degradation of TCS remains largely unexplored. Here, we demonstrated anaerobic biotransformation of TCS in a batch microcosm established with freshwater sediment. The initial 43.4 ± 2.2 μM TCS was completely dechlorinated to diclosan, followed by subsequent conversion to 5-chloro-2-phenoxyphenol, a monochlorinated TCS (MCS) congener. Analyses of community profile and population dynamics revealed substrate-specific, temporal-growth of Dehalococcoides and Dehalogenimonas, which are organohalide-respiring bacteria (OHRB) affiliated with class Dehalococcoidia. Dehalococcoides growth was linked to the formation of diclosan but not MCS, yielding 3.6 ± 0.4 × 107 cells per μmol chloride released. A significant increase in Dehalogenimonas cells, from 1.5 ± 0.4 × 104 to 1.5 ± 0.3 × 106 mL-1, only occurred during the reductive dechlorination of diclosan to MCS. Dehalococcoidia OHRB gradually disappeared following consecutive transfers, likely due to the removal of sediment materials with strong adsorption capacity that could alleviate TCS's antimicrobial toxicity. Consequently, a solid-free, functionally stable TCS-dechlorinating consortium was not obtained. Our results provide insights into the microbial determinants controlling the environmental fate of TCS.
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Affiliation(s)
- Xiuying Li
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, Liaoning 110016, China
- Liaoning Technical Innovation Center for Ecological Restoration of Polluted Environment, Shenyang, Liaoning 110016, China
| | - Jingjing Wang
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, Liaoning 110016, China
- Liaoning Technical Innovation Center for Ecological Restoration of Polluted Environment, Shenyang, Liaoning 110016, China
| | - Yi Yang
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, Liaoning 110016, China
- Liaoning Technical Innovation Center for Ecological Restoration of Polluted Environment, Shenyang, Liaoning 110016, China
| | - Huijuan Jin
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, Liaoning 110016, China
- Liaoning Technical Innovation Center for Ecological Restoration of Polluted Environment, Shenyang, Liaoning 110016, China
| | - Hongyan Wang
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, Liaoning 110016, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhipeng Zhang
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, Liaoning 110016, China
- College of Bioscience and Biotechnology, Shenyang Agricultural University, Shenyang 110866, China
| | - Xiaocui Li
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, Liaoning 110016, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yiru Cui
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, Liaoning 110016, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xin Wang
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, Liaoning 110016, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jun Yan
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Shenyang, Liaoning 110016, China
- Liaoning Technical Innovation Center for Ecological Restoration of Polluted Environment, Shenyang, Liaoning 110016, China
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2
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Pan P, Gu Y, Li T, Zhou NY, Xu Y. Deciphering the triclosan degradation mechanism in Sphingomonas sp. strain YL-JM2C: Implications for wastewater treatment and marine resources. JOURNAL OF HAZARDOUS MATERIALS 2024; 478:135511. [PMID: 39173390 DOI: 10.1016/j.jhazmat.2024.135511] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2024] [Revised: 07/16/2024] [Accepted: 08/12/2024] [Indexed: 08/24/2024]
Abstract
Triclosan (TCS), an antimicrobial agent extensively incorporated into pharmaceuticals and personal care products, poses significant environmental risks because of its persistence and ecotoxicity. So far, a few microorganisms were suggested to degrade TCS, but the microbial degradation mechanism remains elusive. Here, a two-component angular dioxygenase (TcsAaAb) responsible for the initial TCS degradation was characterized in Sphingomonas sp. strain YL-JM2C. Whole-cell biotransformation and crude enzyme assays demonstrated that TcsAaAb catalyzed the conversion of TCS to 4-chlorocatechol and 3,5-dichlorocatechol rather than the commonly suggested product 2,4-dichlorophenol. Then two intermediates were catabolized by tcsCDEF cluster via an ortho-cleavage pathway. Critical residues (N262, F279, and F391) for substrate binding were identified via molecular docking and mutagenesis. Further, TcsAaAb showed activity toward methyl triclosan and nitrofen, suggesting its versatile potential for bioremediation. In addition, TCS-degrading genes were also present in diverse bacterial genomes in wastewater, ocean and soil, and a relatively high gene abundance was observed in marine metagenomes, revealing the transformation fate of TCS in environments and the microbial potential in pollutant removal. These findings extend the understanding of the microbe-mediated TCS degradation and contribute to the mining of TCS-degrading strains and enzymes, as well as their application in the bioremediation of contaminated environments.
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Affiliation(s)
- Piaopiao Pan
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 200240 Shanghai, China
| | - Yichao Gu
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 200240 Shanghai, China
| | - Tao Li
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 200240 Shanghai, China
| | - Ning-Yi Zhou
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 200240 Shanghai, China
| | - Ying Xu
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, 200240 Shanghai, China.
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3
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Chen SH, Li ZT, Lai CY, Zhao HP. Enhancing reductive dechlorination of trichloroethylene in bioelectrochemical systems with conductive materials. ENVIRONMENTAL RESEARCH 2024; 261:119773. [PMID: 39128662 DOI: 10.1016/j.envres.2024.119773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2024] [Revised: 08/08/2024] [Accepted: 08/09/2024] [Indexed: 08/13/2024]
Abstract
The incorporation of conductive materials to enhance electron transfer in bioelectrochemical systems (BES) is considered a promising approach. However, the specific effects and mechanisms of these materials on trichloroethylene (TCE) reductive dechlorination in BES remains are not fully understood. This study investigated the use of magnetite nanoparticles (MNP) and biochars (BC) as coatings on biocathodes for TCE reduction. Results demonstrated that the average dechlorination rates of MNP-Biocathode (122.89 μM Cl·d-1) and BC-Biocathode (102.88 μM Cl·d-1) were greatly higher than that of Biocathode (78.17 μM Cl·d-1). Based on MATLAB calculation, the dechlorination rate exhibited a more significantly increase in TCE-to-DCE step than the other dechlorination steps. Microbial community analyses revealed an increase in the relative abundance of electroactive and dechlorinating populations (e.g., Pseudomonas, Geobacter, and Desulfovibrio) in MNP-Biocathode and BC-Biocathode. Functional gene analysis via RT-qPCR showed the expression of dehalogenase (RDase) and direct electron transfer (DET) related genes was upregulated with the addition of MNP and BC. These findings suggest that conductive materials might accelerate reductive dechlorination by enhancing DET. The difference of physicochemical characteristics (e.g. particle size and specific surface area), electron transfer enhancement mechanism between MNP and BC as well as the reduction of Fe(III) by hydrogen may explain the superior dechlorination rate observed with MNP-Biocathode.
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Affiliation(s)
- Su-Hao Chen
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China
| | - Zheng-Tao Li
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China
| | - Chun-Yu Lai
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China
| | - He-Ping Zhao
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China.
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Yin Y, Ren H, Wu H, Lu Z. Triclosan Dioxygenase: A Novel Two-component Rieske Nonheme Iron Ring-hydroxylating Dioxygenase Initiates Triclosan Degradation. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:13833-13844. [PMID: 39012163 DOI: 10.1021/acs.est.4c02845] [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: 07/17/2024]
Abstract
The emerging contaminant triclosan (TCS) is widely distributed both in surface water and in wastewater and poses a threat to aquatic organisms and human health due to its resistance to degradation. The dioxygenase enzyme TcsAB has been speculated to perform the initial degradation of TCS, but its precise catalytic mechanism remains unclear. In this study, the function of TcsAB was elucidated using multiple biochemical and molecular biology methods. Escherichia coli BL21(DE3) heterologously expressing tcsAB from Sphingomonas sp. RD1 converted TCS to 2,4-dichlorophenol. TcsAB belongs to the group IA family of two-component Rieske nonheme iron ring-hydroxylating dioxygenases. The highest amino acid identity of TcsA and the large subunits of other dioxygenases in the same family was only 35.50%, indicating that TcsAB is a novel dioxygenase. Mutagenesis of residues near the substrate binding pocket decreased the TCS-degrading activity and narrowed the substrate spectrum, except for the TcsAF343A mutant. A meta-analysis of 1492 samples from wastewater treatment systems worldwide revealed that tcsA genes are widely distributed. This study is the first to report that the TCS-specific dioxygenase TcsAB is responsible for the initial degradation of TCS. Studying the microbial degradation mechanism of TCS is crucial for removing this pollutant from the environment.
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Affiliation(s)
- Yiran Yin
- MOE Laboratory of Biosystem Homeostasis and Protection, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
- Cancer Center, Zhejiang University, Hangzhou 310058, China
| | - Hao Ren
- MOE Laboratory of Biosystem Homeostasis and Protection, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
- Cancer Center, Zhejiang University, Hangzhou 310058, China
| | - Hao Wu
- MOE Laboratory of Biosystem Homeostasis and Protection, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
- Cancer Center, Zhejiang University, Hangzhou 310058, China
| | - Zhenmei Lu
- MOE Laboratory of Biosystem Homeostasis and Protection, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
- Cancer Center, Zhejiang University, Hangzhou 310058, China
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5
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Lu Q, Liang Q, Wang S. Burning question: Rethinking organohalide degradation strategy for bioremediation applications. Microb Biotechnol 2024; 17:e14539. [PMID: 39075849 PMCID: PMC11286677 DOI: 10.1111/1751-7915.14539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2024] [Accepted: 07/12/2024] [Indexed: 07/31/2024] Open
Abstract
Organohalides are widespread pollutants that pose significant environmental hazards due to their high degree of halogenation and elevated redox potentials, making them resistant to natural attenuation. Traditional bioremediation approaches, primarily relying on bioaugmentation and biostimulation, often fall short of achieving complete detoxification. Furthermore, the emergence of complex halogenated pollutants, such as per- and polyfluoroalkyl substances (PFASs), further complicates remediation efforts. Therefore, there is a pressing need to reconsider novel approaches for more efficient remediation of these recalcitrant pollutants. This review proposes novel redox-potential-mediated hybrid bioprocesses, tailored to the physicochemical properties of pollutants and their environmental contexts, to achieve complete detoxification of organohalides. The possible scenarios for the proposed bioremediation approaches are further discussed. In anaerobic environments, such as sediment and groundwater, microbial reductive dehalogenation coupled with fermentation and methanogenesis can convert organohalides into carbon dioxide and methane. In environments with anaerobic-aerobic alternation, such as paddy soil and wetlands, a synergistic process involving reduction and oxidation can facilitate the complete mineralization of highly halogenated organic compounds. Future research should focus on in-depth exploration of microbial consortia, the application of ecological principles-guided strategies, and the development of bioinspired-designed techniques. This paper contributes to the academic discourse by proposing innovative remediation strategies tailored to the complexities of organohalide pollution.
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Affiliation(s)
- Qihong Lu
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai)Sun Yat‐Sen UniversityGuangzhouChina
| | - Qi Liang
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai)Sun Yat‐Sen UniversityGuangzhouChina
| | - Shanquan Wang
- School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai)Sun Yat‐Sen UniversityGuangzhouChina
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6
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Xu X, Jiang H, Lu Q, Wang S. Pre-exposure of Triclosan compromise tetracycline-derived antibiotic resistance in methanogenic digestion microbiome. BIORESOURCE TECHNOLOGY 2024; 401:130758. [PMID: 38692374 DOI: 10.1016/j.biortech.2024.130758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2024] [Revised: 04/27/2024] [Accepted: 04/28/2024] [Indexed: 05/03/2024]
Abstract
Triclosan (TCS) and tetracycline (TC) are commonly detected antibacterial agents in sewage and environment matrices. Nonetheless, the impact of sequential exposure to TCS and TC on the methanogenic digestion microbiome remains unknown. In this study, TCS was shown to reduce COD removal efficiency to 69.8%, but alleviated the inhibitive effect of consequent TC-amendment on the digestion microbiome. Interestingly, TCS pre-exposure resulted in abundance increase of acetotrophic Methanosaeta to 2.68%, being 2.91 folds higher than that without TCS amendment. Microbial network analyses showed that TCS pre-exposure caused microorganisms to establish a co-ecological relationship against TC disturbance. Further analyses of total antibiotic resistance genes (ARGs) showed the TCS-derived compromise of TC-induced ARGs enrichment in digestion microbiomes, e.g., 238.2% and 152.1% ARGs increase upon TC addition in digestion microbiomes without and with TCS pre-exposure, respectively. This study provides new insights into the impact of antibacterial agents on the methanogenic digestion microbiome.
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Affiliation(s)
- Xiangping Xu
- School of Environmental Science and Engineering, Environmental Microbiomics Research Center, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-Sen University, Guangzhou 510006, China
| | - Haihong Jiang
- School of Environmental Science and Engineering, Environmental Microbiomics Research Center, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-Sen University, Guangzhou 510006, China
| | - Qihong Lu
- School of Environmental Science and Engineering, Environmental Microbiomics Research Center, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-Sen University, Guangzhou 510006, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou 510006, China
| | - Shanquan Wang
- School of Environmental Science and Engineering, Environmental Microbiomics Research Center, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-Sen University, Guangzhou 510006, China; Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou 510006, China.
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7
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Ma J, Li Y, Zhang X, Li J, Lin Q, Zhu Y, Ruan Z, Ni Z, Qiu R. Modified nano zero-valent iron coupling microorganisms to degrade BDE-209: Degradation pathways and microbial responses. JOURNAL OF HAZARDOUS MATERIALS 2024; 465:133378. [PMID: 38160554 DOI: 10.1016/j.jhazmat.2023.133378] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 12/24/2023] [Accepted: 12/25/2023] [Indexed: 01/03/2024]
Abstract
Polybrominated diphenyl ethers (PBDEs) in soil and groundwater have garnered considerable attention owing to the significant bioaccumulation potential and toxicity. Currently, the coupling treatment method of nano zero-valent iron (nZVI) with dehalogenation microorganisms is a research hotspot in the field of PBDE degradation. In this study, various systems were established within anaerobic environments, including the nZVI-only system, microorganism-only system, and the nZVI + microorganisms system. The aim was to investigate the degradation pathway of BDE-209 and elucidate the degradation mechanism within the coupled system. The results indicated that the degradation efficiency of the coupled system was better than that of the nZVI-only or microorganism-only system. Two modified nZVI (carboxymethyl cellulose and polyacrylamide) were prepared to improve the coupling degradation efficiency. CMC-nZVI showed the highest stability, and the coupled system consisting of microorganisms and CMC-nZVI showed the best degradation effect among all of the systems in this study, reaching 89.53% within 30 days. Furthermore, 22 intermediate products were detected in the coupling systems. Notably, changing the inoculation time did not significantly improve the degradation effect. The expression changes of the two reductive dehalogenase genes, e.g. TceA and Vcr, reflected the stress response and self-recovery ability of the dehalogenating bacteria, indicating such genes can be used as biomarker for evaluating the degradation performance of the coupling system. These findings provide a better understanding about the mechanism of coupling debromination process and the direction for the optimization and on-site repair of coupled systems.
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Affiliation(s)
- Jing Ma
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong Provincial Key Laboratory of Agricultural & Rural Pollution Abatement and Environmental Safety, College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510642, China
| | - Yingping Li
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong Provincial Key Laboratory of Agricultural & Rural Pollution Abatement and Environmental Safety, College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510642, China
| | - Xing Zhang
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong Provincial Key Laboratory of Agricultural & Rural Pollution Abatement and Environmental Safety, College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510642, China
| | - Jingjing Li
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong Provincial Key Laboratory of Agricultural & Rural Pollution Abatement and Environmental Safety, College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510642, China
| | - Qingqi Lin
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong Provincial Key Laboratory of Agricultural & Rural Pollution Abatement and Environmental Safety, College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510642, China
| | - Yanping Zhu
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong Provincial Key Laboratory of Agricultural & Rural Pollution Abatement and Environmental Safety, College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510642, China
| | - Zhepu Ruan
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong Provincial Key Laboratory of Agricultural & Rural Pollution Abatement and Environmental Safety, College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510642, China
| | - Zhuobiao Ni
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong Provincial Key Laboratory of Agricultural & Rural Pollution Abatement and Environmental Safety, College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510642, China.
| | - Rongliang Qiu
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong Provincial Key Laboratory of Agricultural & Rural Pollution Abatement and Environmental Safety, College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510642, China; School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510006, China.
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Liu M, Su X, Yuan J, Chen Y, Huang X, Yang X, Zheng J, Li Q, Xu J, He Y. Residual effects of chlorinated organic pollutants on microbial community and natural redox processes in coastal wetlands. JOURNAL OF HAZARDOUS MATERIALS 2024; 465:133364. [PMID: 38176260 DOI: 10.1016/j.jhazmat.2023.133364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2023] [Revised: 12/11/2023] [Accepted: 12/22/2023] [Indexed: 01/06/2024]
Abstract
Chlorinated organic pollutants (COPs) are common in flooded environments. To examine the residual status and effects of COPs on flooded environments, a survey of 7 coastal wetlands in Zhejiang, East China was conducted. Total COP concentrations detected from 95.69 to 412.76 ng g-1 dw. Gamma-HCH and o,p'-DDT posed the greatest risk with exceedance rates of 100% according to sediment quality guidelines. Samples with higher COP pollution had higher microbial diversity, more complex microbial networks, more deterministic community assembly processes and lower microbiome stability, indicating an improved soil function for balance cycle of substances, especially for COP degradation. Further analysis using quantitative real-time PCR suggested COP-dechlorination interacted with natural redox processes, especially sulfate reduction and methanogenesis. The positive correlation between CH4 and pentachlorobenzene indicated a potential increase in greenhouse gas emissions caused by COP pollution. Correlation between dsr gene and COPs demonstrated the ability of sulfate-reducing bacteria to degrade COPs. Particularly, facultative OHRB such as sulfate-reducing bacteria hold significant importance in the process of COP-dechlorination. This finding provides a reference for COP pollution remediation. Collectively, our study offers new insight into the residual effect of COPs in coastal wetlands and contributes to an improved understanding of bioremediation strategies for COP pollution.
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Affiliation(s)
- Meng Liu
- Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Xin Su
- Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Jing Yuan
- Department of Urban Studies and Planning, Massachusetts Institute of Technology, Cambridge, MA 02139, USA
| | - Yuxuan Chen
- Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Xiaowei Huang
- Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Xueling Yang
- Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Jinjin Zheng
- Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Qinfen Li
- Environmental and Plant Protection Institute, Chinese Academy of Tropical Agricultural Sciences, Haikou, 571101, Hainan, China
| | - Jianming Xu
- Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Yan He
- Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China; Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, Hangzhou 310058, China.
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9
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Chen C, Xu G, Rogers MJ, He J. Metabolic Synergy of Dehalococcoides Populations Leading to Greater Reductive Dechlorination of Polychlorinated Biphenyls. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:2384-2392. [PMID: 38266236 DOI: 10.1021/acs.est.3c08473] [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: 01/26/2024]
Abstract
Polychlorinated biphenyls (PCBs) are dioxin-like pollutants that cause persistent harm to life. Organohalide-respiring bacteria (OHRB) can detoxify PCBs via reductive dechlorination, but individual OHRB are potent in dechlorinating only specific PCB congeners, restricting the extent of PCB dechlorination. Moreover, the low biomass of OHRB frequently leads to the slow natural attenuation of PCBs at contaminated sites. Here we constructed defined microbial consortia comprising various combinations of PCB-dechlorinating Dehalococcoides strains (CG1, CG4, and CG5) to successfully enhance PCB dechlorination. Specifically, the defined consortia consisting of strains CG1 and CG4 removed 0.28-0.44 and 0.23-0.25 more chlorine per PCB from Aroclor1260 and Aroclor1254, respectively, compared to individual strains, which was attributed to the emergence of new PCB dechlorination pathways in defined consortia. Notably, different Dehalococcoides populations exhibited similar growth when cocultivated, but temporal differences in the expression of PCB reductive dehalogenase genes indicated their metabolic synergy. Bioaugmentation with individual strains (CG1, CG4, and CG5) or defined consortia led to greater PCB dechlorination in wetland sediments, and augmentation with the consortium comprising strains CG1 and CG4 resulted in the greatest PCB dechlorination. These findings collectively suggest that simultaneous application of multiple Dehalococcoides strains, which catalyze complementary dechlorination pathways, is an effective strategy to accelerate PCB dechlorination.
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Affiliation(s)
- Chen Chen
- Department of Civil and Environmental Engineering, National University of Singapore, Singapore 117576, Singapore
| | - Guofang Xu
- Department of Civil and Environmental Engineering, National University of Singapore, Singapore 117576, Singapore
| | - Matthew James Rogers
- Department of Civil and Environmental Engineering, National University of Singapore, Singapore 117576, Singapore
| | - Jianzhong He
- Department of Civil and Environmental Engineering, National University of Singapore, Singapore 117576, Singapore
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10
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Chen C, Xu G, He J. Substrate-dependent strategies to mitigate sulfate inhibition on microbial reductive dechlorination of polychlorinated biphenyls. CHEMOSPHERE 2023; 342:140063. [PMID: 37673179 DOI: 10.1016/j.chemosphere.2023.140063] [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: 06/08/2023] [Revised: 08/30/2023] [Accepted: 09/02/2023] [Indexed: 09/08/2023]
Abstract
Sulfate widely co-exists with polychlorinated biphenyls (PCBs) at various concentrations in the subsurface environment. Previous studies have suggested that sulfate often hampers microbial degradation of aliphatic chlorinated solvents such as chloroethenes. However, the impact of sulfate on microbial reductive dechlorination of aromatic PCBs and the underlying mechanisms have received limited attention. Likewise, strategies to mitigate such inhibition remain scarce. Here we found that the mechanisms and mitigation strategies of sulfate inhibition on PCB dechlorination were substrate-dependent. Under electron donor-limiting conditions, even a low concentration of sulfate (2 mM) resulted in a decreased PCB dechlorination rate by 88.7% in a co-culture comprising Dehalococcoides mccartyi CG1 and the sulfate-reducing bacterium Desulfovibrio desulfuricans F1, an inhibition which was attributed to the competition for electron donor between sulfate reduction and PCB dechlorination. As expected, re-amendment of 5 mM lactate effectively re-initiated PCB dechlorination. However, in the presence of a higher concentration of sulfate (5 mM), the PCB dechlorination rate in the co-culture was 77.7% lower than in the control, even with excessive electron donor supply. This inhibition was linked to high concentration of sulfide (∼5 mM) produced from sulfate reduction, as suggested by high availability of electron donor, recovery of dechlorination activity after removal of sulfide, and negligible influence of sulfate on PCB dechlorination in the axenic culture of D. mccartyi CG1. Indeed, sulfide (>5 mM) was found to directly suppress expression of PCB-dechlorinating reductive dehalogenase gene. The highest transcriptional level of pcbA1 was 2.9 ± 0.3 transcripts·cell-1 in the presence of ∼5 mM sulfide, which was increased to 37.4 ± 5.0 transcripts·cell-1 when sulfide was removed. Under this scenario, introduction of ferrous salts (5 mM) efficiently alleviated sulfide inhibition on PCB dechlorination. Interestingly, the augmentation of methanogens in the co-culture was also effective in mitigating sulfide inhibition on PCB dechlorination, offering a new approach to protect Dehalococcoides under sulfide stress. Collectively, these findings deepen our understanding of the influence of sulfate on microbial reductive dechlorination of PCBs and contribute to developing appropriate strategies based on geochemical conditions to alleviate sulfate inhibition during bioremediation of PCB-contaminated sites.
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Affiliation(s)
- Chen Chen
- Department of Civil and Environmental Engineering, National University of Singapore, 117576, Singapore
| | - Guofang Xu
- Department of Civil and Environmental Engineering, National University of Singapore, 117576, Singapore
| | - Jianzhong He
- Department of Civil and Environmental Engineering, National University of Singapore, 117576, Singapore.
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11
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Li ZT, Yang SY, Zhao HP. The effects of arsenic on dechlorination of trichloroethene by consortium DH: Microbial response and resistance. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 896:165219. [PMID: 37392873 DOI: 10.1016/j.scitotenv.2023.165219] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Revised: 06/27/2023] [Accepted: 06/28/2023] [Indexed: 07/03/2023]
Abstract
Inorganic arsenic and organochlorines are frequently co-occurring contaminants in anoxic groundwater environments, and the bioremediation of their composite pollution has long been a rigorous predicament. Currently, the dechlorination behaviors and stress responses of microbial dechlorination consortia to arsenic are not yet fully understood. This study assessed the reductive dechlorination performance of a Dehalococcoides-bearing microcosm DH under gradient concentrations of arsenate [As(V)] or arsenite [As(III)] and investigated the response patterns of different functional microorganisms. Our results demonstrated that although the dechlorination rates declined with increasing arsenic concentrations in both As(III/V) scenarios, the inhibitory impact was more pronounced in As(III)-amended groups compared to As(V)-amended groups. Moreover, the vinyl chloride (VC)-to-ethene step was more susceptible to arsenic exposure compared to the trichloroethene (TCE)-to-dichloroethane (DCE) step, while high levels of arsenic exposure [e.g. As(III) > 75 μM] can induce significant accumulation of VC. Functional gene variations and microbial community analyses revealed that As(III/V) affected reductive dechlorination by directly inhibiting organohalide-respiring bacteria (OHRB) and indirectly inhibiting synergistic populations such as acetogens. Metagenomic results indicated that arsenic metabolic and efflux mechanisms were identical among different Dhc strains, and variations in arsenic uptake pathways were possibly responsible for their differential responses to arsenic exposures. By comparison, fermentative bacteria showed high potential for arsenic resistance due to their inherent advantages in arsenic detoxification and efflux mechanisms. Collectively, our findings expanded the understanding of the response patterns of different functional populations to arsenic stress in the dechlorinating consortium and provided insights into modifying bioremediation strategies at co-contaminated sites for furtherance.
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Affiliation(s)
- Zheng-Tao Li
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310030, PR China
| | - Si-Ying Yang
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310030, PR China
| | - He-Ping Zhao
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, Zhejiang 310030, PR China.
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12
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Qiu L, Guo X, Liang Z, Lu Q, Wang S, Shim H. Uncovering the metabolic pathway of novel Burkholderia sp. for efficient triclosan degradation and implication: Insight from exogenous bioaugmentation and toxicity pressure. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 334:122111. [PMID: 37392866 DOI: 10.1016/j.envpol.2023.122111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/12/2023] [Revised: 06/20/2023] [Accepted: 06/24/2023] [Indexed: 07/03/2023]
Abstract
Triclosan (TCS), a synthetic and broad-spectrum antimicrobial agent, is frequently detected in various environmental matrices. A novel TCS degrading bacterial strain, Burkholderia sp. L303, was isolated from local activated sludge. The strain could metabolically degrade TCS up to 8 mg/L, and optimal conditions for TCS degradation were at temperature of 35 °C, pH 7, and an increased inoculum size. During TCS degradation, several intermediates were identified, with the initial degradation occurring mainly through hydroxylation of aromatic ring, followed by dechlorination. Further intermediates such as 2-chlorohydroquinone, 4-chlorocatechol, and 4-chlorophenol were produced via ether bond fission and C-C bond cleavage, which could be further transformed into unchlorinated compounds, ultimately resulting in the complete stoichiometric free chloride release. Bioaugmentation of strain L303 in non-sterile river water demonstrated better degradation than in sterile water. Further exploration of the microbial communities provided insights into the composition and succession of the microbial communities under the TCS stress as well as during the TCS biodegradation process in real water samples, the key microorganisms involved in TCS biodegradation or showing resistance to the TCS toxicity, and the changes in microbial diversity related to exogenous bioaugmentation, TCS input, and TCS elimination. These findings shed light on the metabolic degradation pathway of TCS and highlight the significance of microbial communities in the bioremediation of TCS-contaminated environments.
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Affiliation(s)
- Lan Qiu
- Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau SAR, China
| | - Xiaoyuan Guo
- Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau SAR, China
| | - Zhiwei Liang
- Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau SAR, China; Department of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou, China
| | - Qihong Lu
- Department of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou, China
| | - Shanquan Wang
- Department of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou, China
| | - Hojae Shim
- Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau SAR, China.
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13
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Xiang Y, Li S, Rene ER, Lun X, Zhang P, Ma W. Detoxification of fluoroglucocorticoid by Acinetobacter pittii C3 via a novel defluorination pathway with hydrolysis, oxidation and reduction: Performance, genomic characteristics, and mechanism. JOURNAL OF HAZARDOUS MATERIALS 2023; 452:131302. [PMID: 37031670 DOI: 10.1016/j.jhazmat.2023.131302] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2023] [Revised: 03/10/2023] [Accepted: 03/24/2023] [Indexed: 05/03/2023]
Abstract
Biological dehalogenation degradation was an important detoxification method for the ecotoxicity and teratogenic toxicity of fluorocorticosteroids (FGCs). The functional strain Acinetobacter pittii C3 can effectively biodegrade and defluorinate to 1 mg/L Triamcinolone acetonide (TA), a representative FGCs, with 86 % and 79 % removal proportion in 168 h with the biodegradation and detoxification kinetic constant of 0.031/h and 0.016/h. The dehalogenation and degradation ability of strain C3 was related to its dehalogenation genomic characteristics, which manifested in the functional gene expression of dehalogenation, degradation, and toxicity tolerance. Three detoxification mechanisms were positively correlated with defluorination pathways through hydrolysis, oxidation, and reduction, which were regulated by the expression of the haloacid dehalogenase (HAD) gene (mupP, yrfG, and gph), oxygenase gene (dmpA and catA), and reductase gene (nrdAB and TgnAB). Hydrolysis defluorination was the most critical way for TA detoxification metabolism, which could rapidly generate low-toxicity metabolites and reduce toxic bioaccumulation due to hydrolytic dehalogenase-induced defluorination. The mechanism of hydrolytic defluorination was that the active pocket of hydrolytic dehalogenase was matched well with the spatial structure of TA under the adjustment of the hydrogen bond, and thus induced molecular recognition to promote the catalytic hydrolytic degradation of various amino acid residues. This work provided an effective bioremediation method and mechanism for improving defluorination and detoxification performance.
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Affiliation(s)
- Yayun Xiang
- College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
| | - Sinuo Li
- Beijing No. 80 High School, Beijing 100102, China
| | - Eldon R Rene
- IHE-Delft, Institute for Water Education, Department of Environmental Engineering and Water Technology, Westvest 7, 2611AX Delft, the Netherlands
| | - Xiaoxiu Lun
- College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
| | - Panyue Zhang
- College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China
| | - Weifang Ma
- College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China.
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14
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Wu Z, Yu X, Liu G, Li W, Lu L, Li P, Xu X, Jiang J, Wang B, Qiao W. Sustained detoxification of 1,2-dichloroethane to ethylene by a symbiotic consortium containing Dehalococcoides species. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 325:121443. [PMID: 36921661 DOI: 10.1016/j.envpol.2023.121443] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/05/2022] [Revised: 02/19/2023] [Accepted: 03/11/2023] [Indexed: 06/18/2023]
Abstract
1,2-Dichloroethane (1,2-DCA) is a ubiquitous volatile halogenated organic pollutant in groundwater and soil, which poses a serious threat to the ecosystem and human health. Microbial reductive dechlorination has been recognized as an environmentally-friendly strategy for the remediation of sites contaminated with 1,2-DCA. In this study, we obtained an anaerobic microbiota derived from 1,2-DCA contaminated groundwater, which was able to sustainably convert 1,2-DCA into non-toxic ethylene with an average dechlorination rate of 30.70 ± 11.06 μM d-1 (N = 6). The microbial community profile demonstrated that the relative abundance of Dehalococcoides species increased from 0.53 ± 0.08% to 44.68 ± 3.61% in parallel with the dechlorination of 1,2-DCA. Quantitative PCR results showed that the Dehalococcoides species 16S rRNA gene increased from 2.40 ± 1.71 × 108 copies∙mL-1 culture to 4.07 ± 2.45 × 108 copies∙mL-1 culture after dechlorinating 110.69 ± 30.61 μmol of 1,2-DCA with a growth yield of 1.55 ± 0.93 × 108 cells per μmol Cl- released (N = 6), suggesting that Dehalococcoides species used 1,2-DCA for organohalide respiration to maintain cell growth. Notably, the relative abundances of Methanobacterium sp. (p = 0.0618) and Desulfovibrio sp. (p = 0.0001995) also increased significantly during the dechlorination of 1,2-DCA and were clustered in the same module with Dehalococcoides species in the co-occurrence network. These results hinted that Dehalococcoides species, the obligate organohalide-respiring bacterium, exhibited potential symbiotic relationships with Methanobacterium and Desulfovibrio species. This study illustrates the importance of microbial interactions within functional microbiota and provides a promising microbial resource for in situ bioremediation in sites contaminated with 1,2-DCA.
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Affiliation(s)
- Zhiming Wu
- Department of Microbiology, Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Xin Yu
- Department of Microbiology, Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Guiping Liu
- Department of Microbiology, Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Wei Li
- Department of Microbiology, Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Lianghua Lu
- Jiangsu Provincial Key Laboratory of Environmental Engineering, Jiangsu Provincial Academy of Environmental Science, Nanjing 210036, China
| | - Pengfa Li
- Department of Microbiology, Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Xihui Xu
- Department of Microbiology, Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Jiandong Jiang
- Department of Microbiology, Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Baozhan Wang
- Department of Microbiology, Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China
| | - Wenjing Qiao
- Department of Microbiology, Key Laboratory of Agricultural and Environmental Microbiology, Ministry of Agriculture and Rural Affairs, College of Life Sciences, Nanjing Agricultural University, Nanjing 210095, China.
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15
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Community-integrated multi-omics facilitates screening and isolation of the organohalide dehalogenation microorganism. Innovation (N Y) 2022; 4:100355. [PMID: 36506298 PMCID: PMC9730224 DOI: 10.1016/j.xinn.2022.100355] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2022] [Accepted: 11/17/2022] [Indexed: 11/23/2022] Open
Abstract
A variety of anthropogenic organohalide contaminants generated from industry are released into the environment and thus cause serious pollution that endangers human health. In the present study, we investigated the microbial community composition of industrial saponification wastewater using 16S rRNA sequencing, providing genomic insights of potential organohalide dehalogenation bacteria (OHDBs) by metagenomic sequencing. We also explored yet-to-culture OHDBs involved in the microbial community. Microbial diversity analysis reveals that Proteobacteria and Patescibacteria phyla dominate microbiome abundance of the wastewater. In addition, a total of six bacterial groups (Rhizobiales, Rhodobacteraceae, Rhodospirillales, Flavob a cteriales, Micrococcales, and Saccharimonadales) were found as biomarkers in the key organohalide removal module. Ninety-four metagenome-assembled genomes were reconstructed from the microbial community, and 105 hydrolytic dehalogenase genes within 42 metagenome-assembled genomes were identified, suggesting that the potential for organohalide hydrolytic dehalogenation is present in the microbial community. Subsequently, we characterized the organohalide dehalogenation of an isolated OHDB, Microbacterium sp. J1-1, which shows the dehalogenation activities of chloropropanol, dichloropropanol, and epichlorohydrin. This study provides a community-integrated multi-omics approach to gain functional OHDBs for industrial organohalide dehalogenation.
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16
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Xu G, He J. Resilience of organohalide-detoxifying microbial community to oxygen stress in sewage sludge. WATER RESEARCH 2022; 224:119055. [PMID: 36126627 DOI: 10.1016/j.watres.2022.119055] [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: 06/27/2022] [Revised: 08/20/2022] [Accepted: 09/02/2022] [Indexed: 06/15/2023]
Abstract
Organohalide pollutants are prevalent in the environment, causing harms to wildlife and human. Organohalide-respiring bacteria (OHRB) could detoxify these pollutants in anaerobic environments, but the most competent OHRB (i.e., Dehalococcoides) is susceptible to oxygen. This study reports exceptional resistance and resilience of sewage sludge microbial communities to oxygen stress for attenuation of structurally distinct organohalide pollutants, including tetrachloroethene, tetrabromobisphenol A, and polybrominated diphenyl ethers. The dehalogenation rate constant of these organohalide pollutants in oxygen-exposed sludge microcosms was maintained as 74-120% as that in the control without oxygen exposure. Subsequent top-down experiments clarified that sludge flocs and non-OHRB contributed to alleviating oxygen stress on OHRB. In the dehalogenating microcosms, multiple OHRB (Dehahlococcoides, Dehalogenimonas, and Sulfurospirillum) harboring distinct reductive dehalogenase genes (pceA, pteA, tceA, vcrA, and bdeA) collaborated to detoxify organohalide pollutants but responded differentially to oxygen stress. Comprehensive microbial community analyses (taxonomy, diversity, and structure) demonstrated certain resilience of the sludge-derived dehalogenating microbial communities to oxygen stress. Additionally, microbial co-occurrence networks were intensified by oxygen stress in most microcosms, as a possible stress mitigation strategy. Altogether the mechanistic and ecological findings in this study contribute to remediation of organohalide-contaminated sites encountering oxygen disturbance.
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Affiliation(s)
- Guofang Xu
- Department of Civil and Environmental Engineering, National University of Singapore, 117576, Singapore; NUS Graduate School - Integrative Sciences and Engineering Programme (ISEP), National University of Singapore, 119077, Singapore
| | - Jianzhong He
- Department of Civil and Environmental Engineering, National University of Singapore, 117576, Singapore; NUS Graduate School - Integrative Sciences and Engineering Programme (ISEP), National University of Singapore, 119077, Singapore.
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17
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Yin Y, Wu H, Jiang Z, Jiang J, Lu Z. Degradation of Triclosan in the Water Environment by Microorganisms: A Review. Microorganisms 2022; 10:microorganisms10091713. [PMID: 36144315 PMCID: PMC9505857 DOI: 10.3390/microorganisms10091713] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Revised: 08/18/2022] [Accepted: 08/22/2022] [Indexed: 11/16/2022] Open
Abstract
Triclosan (TCS), a kind of pharmaceuticals and personal care products (PPCPs), is widely used and has had a large production over years. It is an emerging pollutant in the water environment that has attracted global attention due to its toxic effects on organisms and aquatic ecosystems, and its concentrations in the water environment are expected to increase since the COVID-19 pandemic outbreak. Some researchers found that microbial degradation of TCS is an environmentally sustainable technique that results in the mineralization of large amounts of organic pollutants without toxic by-products. In this review, we focus on the fate of TCS in the water environment, the diversity of TCS-degrading microorganisms, biodegradation pathways and molecular mechanisms, in order to provide a reference for the efficient degradation of TCS and other PPCPs by microorganisms.
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Affiliation(s)
- Yiran Yin
- MOE Laboratory of Biosystem Homeostasis and Protection, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Hao Wu
- MOE Laboratory of Biosystem Homeostasis and Protection, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
| | - Zhenghai Jiang
- Zhejiang Haihe Environmental Technology Co., Ltd., Jinhua 321012, China
| | - Jingwei Jiang
- Zhejiang Haihe Environmental Technology Co., Ltd., Jinhua 321012, China
| | - Zhenmei Lu
- MOE Laboratory of Biosystem Homeostasis and Protection, College of Life Sciences, Zhejiang University, Hangzhou 310058, China
- Correspondence: ; Tel.: +86-0571-88206279
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18
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Li X, Yang Y, Wang J, Jin H, Zhang Y, Cui Y, Song Y, Yan J. Organohalide Respiration with Diclofenac by Dehalogenimonas. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:11266-11276. [PMID: 35921385 DOI: 10.1021/acs.est.1c08824] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Diclofenac (DCF) is a pharmaceutically active contaminant frequently found in aquatic ecosystems. The transformation pathways and microbiology involved in the biodegradation of DCF, particularly under anoxic conditions, remain poorly understood. Here, we demonstrated microbially mediated reductive dechlorination of DCF in anaerobic enrichment culture derived from contaminated river sediment. Over 90% of the initial 76.7 ± 3.6 μM DCF was dechlorinated at a maximum rate of 1.8 ± 0.3 μM day-1 during a 160 days' incubation. Mass spectrometric analysis confirmed that 2-(2-((2-chlorophenyl)amino)phenyl)acetic acid (2-CPA) and 2-anilinophenylacetic acid (2-APA) were formed as the monochlorinated and nonchlorinated DCF transformation products, respectively. A survey of microbial composition and Sanger sequencing revealed the enrichment and dominance of a new Dehalogenimonas population, designated as Dehalogenimonas sp. strain DCF, in the DCF-dechlorinating community. Following the stoichiometric conversion of DCF to 2-CPA (76.0 ± 2.1 μM) and 2-APA (3.7 ± 0.8 μM), strain DCF cell densities increased by 24.4 ± 4.4-fold with a growth yield of 9.0 ± 0.1 × 108 cells per μmol chloride released. Our findings expand the metabolic capability in the genus Dehalogenimonas and highlight the relevant roles of organohalide-respiring bacteria for the natural attenuation of halogenated contaminants of emerging concerns (e.g., DCF).
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Affiliation(s)
- Xiuying Li
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Room 512 South Building, 72 Wenhua Road, Shenyang, Liaoning 110016, China
| | - Yi Yang
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Room 512 South Building, 72 Wenhua Road, Shenyang, Liaoning 110016, China
| | - Jingjing Wang
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Room 512 South Building, 72 Wenhua Road, Shenyang, Liaoning 110016, China
| | - Huijuan Jin
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Room 512 South Building, 72 Wenhua Road, Shenyang, Liaoning 110016, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yaozhi Zhang
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Room 512 South Building, 72 Wenhua Road, Shenyang, Liaoning 110016, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yiru Cui
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Room 512 South Building, 72 Wenhua Road, Shenyang, Liaoning 110016, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yufang Song
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Room 512 South Building, 72 Wenhua Road, Shenyang, Liaoning 110016, China
| | - Jun Yan
- Key Laboratory of Pollution Ecology and Environmental Engineering, Institute of Applied Ecology, Chinese Academy of Sciences, Room 512 South Building, 72 Wenhua Road, Shenyang, Liaoning 110016, China
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19
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Xu G, Ng HL, Chen C, Zhao S, He J. Efficient and Complete Detoxification of Polybrominated Diphenyl Ethers in Sediments Achieved by Bioaugmentation with Dehalococcoides and Microbial Ecological Insights. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:8008-8019. [PMID: 35549250 DOI: 10.1021/acs.est.2c00914] [Citation(s) in RCA: 25] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Polybrominated diphenyl ethers (PBDEs) are prevalent environmental pollutants, but bioremediation of PBDEs remains to be reported. Here we report accelerated remediation of a penta-BDE mixture in sediments by bioaugmentation with Dehalococcoides mccartyi strains CG1 and TZ50. Bioaugmentation with different amounts of each Dehalococcoides strain enhanced debromination of penta-BDEs compared with the controls. The sediment microcosm spiked with 6.8 × 106 cells/mL strain CG1 showed the highest penta-BDEs removal (89.9 ± 7.3%) to diphenyl ether within 60 days. Interestingly, co-contaminant tetrachloroethene (PCE) improved bioaugmentation performance, resulting in faster and more extensive penta-BDEs debromination using less bioinoculants, which was also completely dechlorinated to ethene by introducing D. mccartyi strain 11a. The better bioaugmentation performance in sediments with PCE could be attributed to the boosted growth of the augmented Dehalococcoides and capability of the PCE-induced reductive dehalogenases to debrominate penta-BDEs. Finally, ecological analyses showed that bioaugmentation resulted in more deterministic microbial communities, where the augmented Dehalococcoides established linkages with indigenous microorganisms but without causing obvious alterations of the overall community diversity and structure. Collectively, this study demonstrates that bioaugmentation with Dehalococcoides is a feasible strategy to completely remove PBDEs in sediments.
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Affiliation(s)
- Guofang Xu
- Department of Civil and Environmental Engineering, National University of Singapore, Singapore 117576
- NUS Graduate School─Integrative Sciences and Engineering Programme (ISEP), National University of Singapore, Singapore 119077
| | - Hung Liang Ng
- Department of Civil and Environmental Engineering, National University of Singapore, Singapore 117576
| | - Chen Chen
- Department of Civil and Environmental Engineering, National University of Singapore, Singapore 117576
| | - Siyan Zhao
- Department of Civil and Environmental Engineering, National University of Singapore, Singapore 117576
| | - Jianzhong He
- Department of Civil and Environmental Engineering, National University of Singapore, Singapore 117576
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20
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Xu G, Zhao S, Chen C, Zhao X, Ramaswamy R, He J. Dehalogenation of Polybrominated Diphenyl Ethers and Polychlorinated Biphenyls Catalyzed by a Reductive Dehalogenase in Dehalococcoides mccartyi Strain MB. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:4039-4049. [PMID: 35298122 DOI: 10.1021/acs.est.1c05170] [Citation(s) in RCA: 23] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) are notorious persistent organic pollutants. However, few organohalide-respiring bacteria that harbor reductive dehalogenases (RDases) capable of dehalogenating these pollutants have been identified. Here, we report reductive dehalogenation of penta-BDEs and PCBs byDehalococcoides mccartyi strain MB. The PCE-pregrown cultures of strain MB debrominated 86.6 ± 7.4% penta-BDEs to di- to tetra-BDEs within 5 days. Similarly, extensive dechlorination of Aroclor1260 and Aroclor1254 was observed in the PCE-pregrown cultures of strain MB, with the average chlorine per PCB decreasing from 6.40 ± 0.02 and 5.40 ± 0.03 to 5.98 ± 0.11 and 5.19 ± 0.07 within 14 days, respectively; para-substituents were preferentially dechlorinated from PCBs. Moreover, strain MB showed distinct enantioselective dechlorination of different chiral PCB congeners. Dehalogenation activity and cell growth were maintained during the successive transfer of cultures when amended with penta-BDEs as the sole electron acceptors but not when amended with only PCBs, suggesting metabolic and co-metabolic dehalogenation of these compounds, respectively. Transcriptional analysis, proteomic profiling, and in vitro activity assays indicated that MbrA was involved in dehalogenating PCE, PCBs, and PBDEs. Interestingly, resequencing of mbrA in strain MB identified three nonsynonymous mutations within the nucleotide sequence, although the consequences of which remain unknown. The substrate versatility of MbrA enabled strain MB to dechlorinate PCBs in the presence of either penta-BDEs or PCE, suggesting that co-metabolic dehalogenation initiated by multifunctional RDases may contribute to PCB attenuation at sites contaminated with multiple organohalide pollutants.
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Affiliation(s)
- Guofang Xu
- Department of Civil and Environmental Engineering, National University of Singapore, Block E2-02-13, 1 Engineering Drive 3, Singapore 117576, Singapore
- NUS Graduate School - Integrative Sciences and Engineering Programme (ISEP), National University of Singapore, Singapore 119077, Singapore
| | - Siyan Zhao
- Department of Civil and Environmental Engineering, National University of Singapore, Block E2-02-13, 1 Engineering Drive 3, Singapore 117576, Singapore
| | - Chen Chen
- Department of Civil and Environmental Engineering, National University of Singapore, Block E2-02-13, 1 Engineering Drive 3, Singapore 117576, Singapore
| | - Xuejie Zhao
- Department of Civil and Environmental Engineering, National University of Singapore, Block E2-02-13, 1 Engineering Drive 3, Singapore 117576, Singapore
| | - Rajaganesan Ramaswamy
- Department of Civil and Environmental Engineering, National University of Singapore, Block E2-02-13, 1 Engineering Drive 3, Singapore 117576, Singapore
- NUS Graduate School - Integrative Sciences and Engineering Programme (ISEP), National University of Singapore, Singapore 119077, Singapore
| | - Jianzhong He
- Department of Civil and Environmental Engineering, National University of Singapore, Block E2-02-13, 1 Engineering Drive 3, Singapore 117576, Singapore
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21
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Xu G, Zhang N, Zhao X, Chen C, Zhang C, He J. Offshore Marine Sediment Microbiota Respire Structurally Distinct Organohalide Pollutants. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2022; 56:3065-3075. [PMID: 35187933 DOI: 10.1021/acs.est.1c06680] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Marine sediments are a major sink of organohalide pollutants, but the potential for offshore marine microbiota to transform these pollutants remains underexplored. Here, we report dehalogenation of diverse organohalide pollutants by offshore marine microbiota. Dechlorination of polychlorinated biphenyls (PCBs) was observed in four marine sediment microcosms, which was positively correlated with in situ PCB contamination. Three distinct enrichment cultures were enriched from these PCB-dechlorinating microcosms using tetrachloroethene (PCE) as the sole organohalide. All enrichment cultures also dehalogenated polybrominated diphenyl ethers (PBDEs), tetrabromobisphenol A (TBBPA), and 2,4,6-trichlorophenol (2,4,6-TCP). Particularly, two enrichments completely debrominated penta-BDEs, the first observation of complete debromination of penta-BDEs in marine cultures. Multiple Dehalococcoides and uncultivated Dehalococcoidia were identified in the initial sediment microcosms, but only Dehalococcoides was dominant in all enrichments. Transcription of a gene encoding a PcbA5-like reductive dehalogenase (RDase) was observed during dehalogenation of different organohalides in each enrichment culture. When induced by a single organohalide substrate, the PcbA5-like RDase dehalogenated all tested organohalides (PCE, PCBs, PBDEs, TBBPA, and 2,4,6-TCP) in in vitro tests, suggesting its involvement in dehalogenation of structurally distinct organohalides. Our results demonstrate the versatile dehalogenation capacity of marine Dehalococcoidia and contribute to a better understanding of the fate of these pollutants in marine systems.
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Affiliation(s)
- Guofang Xu
- Department of Civil and Environmental Engineering, National University of Singapore, Block E2-02-13, 1 Engineering Drive 3, Singapore 117576, Singapore
- NUS Graduate School─Integrative Sciences and Engineering Programme (ISEP), National University of Singapore, Singapore 119077, Singapore
| | - Ning Zhang
- Department of Civil and Environmental Engineering, National University of Singapore, Block E2-02-13, 1 Engineering Drive 3, Singapore 117576, Singapore
- Institute of Marine Biology and Pharmacology, Ocean College, Zhejiang University, Zhoushan, Zhejiang 316021, China
- College of Chemical Engineering and Pharmacy, Henan University of Science and Technology, Luoyang, Henan 471003, China
| | - Xuejie Zhao
- Department of Civil and Environmental Engineering, National University of Singapore, Block E2-02-13, 1 Engineering Drive 3, Singapore 117576, Singapore
| | - Chen Chen
- Department of Civil and Environmental Engineering, National University of Singapore, Block E2-02-13, 1 Engineering Drive 3, Singapore 117576, Singapore
| | - Chunfang Zhang
- Institute of Marine Biology and Pharmacology, Ocean College, Zhejiang University, Zhoushan, Zhejiang 316021, China
| | - Jianzhong He
- Department of Civil and Environmental Engineering, National University of Singapore, Block E2-02-13, 1 Engineering Drive 3, Singapore 117576, Singapore
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22
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Kennes-Veiga DM, Gónzalez-Gil L, Carballa M, Lema JM. Enzymatic cometabolic biotransformation of organic micropollutants in wastewater treatment plants: A review. BIORESOURCE TECHNOLOGY 2022; 344:126291. [PMID: 34752884 DOI: 10.1016/j.biortech.2021.126291] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 10/28/2021] [Accepted: 11/01/2021] [Indexed: 06/13/2023]
Abstract
Biotransformation of trace-level organic micropollutants (OMPs) by complex microbial communities in wastewater treatment facilities is a key process for their detoxification and environmental impact reduction. Therefore, understanding the metabolic activities and mechanisms that contribute to their biotransformation is essential when developing approaches aiming to minimize their discharge. This review addresses the relevance of cometabolic processes and discusses the main enzymatic activities currently known to take part in OMPs removal under different redox environments in the compartments of wastewater treatment plants. Furthermore, the most common methodologies to decipher such enzymes are discussed, including the use of in vitro enzyme assays, enzymatic inhibitors, the analysis of transformation products and the application of several -omic techniques. Finally, perspectives on major challenges and future research requirements to improve OMPs biotransformation are proposed.
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Affiliation(s)
- David M Kennes-Veiga
- CRETUS, Department of Chemical Engineering, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain.
| | - Lorena Gónzalez-Gil
- Defence University Centre, Spanish Naval Academy, Plaza de España, 36920 Marín, Spain
| | - Marta Carballa
- CRETUS, Department of Chemical Engineering, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - Juan M Lema
- CRETUS, Department of Chemical Engineering, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain
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23
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He H, Li Y, Shen R, Shim H, Zeng Y, Zhao S, Lu Q, Mai B, Wang S. Environmental occurrence and remediation of emerging organohalides: A review. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2021; 290:118060. [PMID: 34479159 DOI: 10.1016/j.envpol.2021.118060] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Revised: 08/02/2021] [Accepted: 08/25/2021] [Indexed: 06/13/2023]
Abstract
As replacements for "old" organohalides, such as polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs), "new" organohalides have been developed, including decabromodiphenyl ethane (DBDPE), short-chain chlorinated paraffins (SCCPs), and perfluorobutyrate (PFBA). In the past decade, these emerging organohalides (EOHs) have been extensively produced as industrial and consumer products, resulting in their widespread environmental distribution. This review comprehensively summarizes the environmental occurrence and remediation methods for typical EOHs. Based on the data collected from 2015 to 2021, these EOHs are widespread in both abiotic (e.g., dust, air, soil, sediment, and water) and biotic (e.g., bird, fish, and human serum) matrices. A significant positive correlation was found between the estimated annual production amounts of EOHs and their environmental contamination levels, suggesting the prohibition of both production and usage of EOHs as a critical pollution-source control strategy. The strengths and weaknesses, as well as the future prospects of up-to-date remediation techniques, such as photodegradation, chemical oxidation, and biodegradation, are critically discussed. Of these remediation techniques, microbial reductive dehalogenation represents a promising in situ remediation method for removal of EOHs, such as perfluoroalkyl and polyfluoroalkyl substances (PFASs) and halogenated flame retardants (HFRs).
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Affiliation(s)
- Haozheng He
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou, 510006, China
| | - Yiyang Li
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou, 510006, China
| | - Rui Shen
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou, 510006, China
| | - Hojae Shim
- Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau SAR, 999078, China
| | - Yanhong Zeng
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
| | - Siyan Zhao
- School of Environmental Science and Engineering, Nanjing Tech University, Nanjing, 211816, China
| | - Qihong Lu
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou, 510006, China; State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China.
| | - Bixian Mai
- State Key Laboratory of Organic Geochemistry and Guangdong Key Laboratory of Environmental Protection and Resources Utilization, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, China
| | - Shanquan Wang
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou, 510006, China
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24
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Xu G, Zhao X, Zhao S, He J. Acceleration of polychlorinated biphenyls remediation in soil via sewage sludge amendment. JOURNAL OF HAZARDOUS MATERIALS 2021; 420:126630. [PMID: 34293691 DOI: 10.1016/j.jhazmat.2021.126630] [Citation(s) in RCA: 29] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/23/2021] [Revised: 07/03/2021] [Accepted: 07/09/2021] [Indexed: 06/13/2023]
Abstract
Bioremediation of polychlorinated biphenyls (PCBs) is impeded by difficulties in massively cultivating bioinoculant. Meanwhile, sewage sludge is rich in pollutant-degrading microorganisms and nutrients, drawing our attention to investigate their potential to be used as a supplement for bioremediation of PCBs. Here we reported extensive microbial reductive dechlorination of PCBs by waste activated sludge (WAS) and digestion sludge (DS), which were identified to harbor multiple putative organohalide-respiring bacteria (i.e., Dehalococcoides, Dehalogenimonas, Dehalobacter, and uncultivated Dehalococcoidia) and PCB reductive dehalogenase genes (i.e., pcbA4 and pcbA5). Consequently, amendment of 1-20% (w/w) fresh WAS/DS enhanced the attenuation of PCBs by 126-544% in a soil microcosm compared with the control soil, with the fastest dechlorination of PCBs being achieved when spiked with 20% fresh WAS. Notably, dechlorination pathways of PCBs were also changed by sludge amendment. Microbial and physicochemical analyses revealed that the enhanced dechlorination of PCBs by sludge amendment was largely attributed to the synergistic effects of sludge-derived nutrients, PCB-dechlorinating bacteria, and stimulated growth of beneficial microorganisms (e.g., fermenters). Finally, risk assessment of heavy metals suggests low potential ecological risks of sludge amendment in soil. Collectively, our study demonstrates that sewage sludge amendment could be an efficient, cost-effective and environment-friendly approach for in situ bioremediation of PCBs.
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Affiliation(s)
- Guofang Xu
- NUS Graduate School - Integrative Sciences and Engineering Programme (ISEP), National University of Singapore, Singapore 119077, Singapore; Department of Civil and Environmental Engineering, National University of Singapore, Block E2-02-13, 1 Engineering Drive 3, Singapore 117576, Singapore
| | - Xuejie Zhao
- Department of Civil and Environmental Engineering, National University of Singapore, Block E2-02-13, 1 Engineering Drive 3, Singapore 117576, Singapore
| | - Siyan Zhao
- Department of Civil and Environmental Engineering, National University of Singapore, Block E2-02-13, 1 Engineering Drive 3, Singapore 117576, Singapore
| | - Jianzhong He
- Department of Civil and Environmental Engineering, National University of Singapore, Block E2-02-13, 1 Engineering Drive 3, Singapore 117576, Singapore.
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25
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Ramaswamy R, Zhao S, Bae S, He J. Debromination of TetraBromoBisphenol-A (TBBPA) depicting the metabolic versatility of Dehalococcoides. JOURNAL OF HAZARDOUS MATERIALS 2021; 419:126408. [PMID: 34174623 DOI: 10.1016/j.jhazmat.2021.126408] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 06/10/2021] [Accepted: 06/12/2021] [Indexed: 06/13/2023]
Abstract
TetraBromoBisphenol-A (TBBPA) is a widely used brominated flame retardant and an emerging contaminant that has amassed significant environmental impacts. Though there are a few studies that report the bioremediation of TBBPA, there is no direct evidence to suggest a metabolic use of TBBPA as the sole electron acceptor, which offers an advantage in the complete and energy-efficient process of debromination under anaerobic conditions. In this study, Dehalococcoides mccartyi strain CG1 was identified to be capable of utilizing TBBPA as the sole electron acceptor at its maximum soluble concentrations (7.3 μM) coupled with cell growth. A previously characterized reductive dehalogenase (RDase), PcbA1, and six other RDases of strain CG1 were detected during TBBPA debromination via transcriptional and proteomic analyses. Furthermore, as a commonly co-contaminated brominated flame retardant of TBBPA, penta-BDEs were debrominated synchronously with TBBPA by strain CG1. This study provides deeper insights into the versatile dehalogenation capabilities of D. mccartyi strain CG1 and its role in in situ remediations of persistent organic pollutants in the environment.
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Affiliation(s)
- Rajaganesan Ramaswamy
- Department of Civil and Environmental Engineering, National University of Singapore, 117576 Singapore, Singapore; Singapore Centre for Environmental Life Sciences and Engineering, National University of Singapore, 117576 Singapore, Singapore
| | - Siyan Zhao
- Department of Civil and Environmental Engineering, National University of Singapore, 117576 Singapore, Singapore
| | - Sungwoo Bae
- Department of Civil and Environmental Engineering, National University of Singapore, 117576 Singapore, Singapore
| | - Jianzhong He
- Department of Civil and Environmental Engineering, National University of Singapore, 117576 Singapore, Singapore.
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26
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Identification of Reductive Dehalogenases That Mediate Complete Debromination of Penta- and Tetrabrominated Diphenyl Ethers in Dehalococcoides spp. Appl Environ Microbiol 2021; 87:e0060221. [PMID: 34160266 DOI: 10.1128/aem.00602-21] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Polybrominated diphenyl ethers (PBDEs) are persistent, highly toxic, and widely distributed environmental pollutants. The microbial populations and functional reductive dehalogenases (RDases) responsible for PBDE debromination in anoxic systems remain poorly understood, which confounds bioremediation of PBDE-contaminated sites. Here, we report a PBDE-debrominating enrichment culture dominated by a previously undescribed Dehalococcoides mccartyi population. A D. mccartyi strain, designated TZ50, whose genome contains 25 putative RDase-encoding genes, was isolated from the debrominating enrichment culture. Strain TZ50 dehalogenated a mixture of pentabrominated diphenyl ether (penta-BDE) and tetra-BDE congeners (total BDEs, 1.48 μM) to diphenyl ether within 2 weeks (0.58 μM Br-/day) via ortho- and meta-bromine elimination; strain TZ50 also dechlorinated tetrachloroethene (PCE) to vinyl chloride and ethene (260.2 μM Cl-/day). Results of native PAGE, proteomic profiling, and in vitro enzymatic activity assays implicated the involvement of three RDases in PBDE and PCE dehalogenation. TZ50_0172 (PteATZ50) and TZ50_1083 (TceATZ50) were responsible for the debromination of penta- and tetra-BDEs to di-BDE. TZ50_0172 and TZ50_1083 were also implicated in the dechlorination of PCE to trichloroethene (TCE) and of TCE to vinyl chloride/ethene, respectively. The other expressed RDase, TZ50_0090 (designated BdeA), was associated with the debromination of di-BDE to diphenyl ether, but its role in PCE dechlorination was unclear. Comparatively few RDases are known to be involved in PBDE debromination, and the identification of PteATZ50, TceATZ50, and BdeA provides additional information for evaluating debromination potential at contaminated sites. Moreover, the ability of PteATZ50 and TceATZ50 to dehalogenate both PBDEs and PCE makes strain TZ50 a suitable candidate for the remediation of cocontaminated sites. IMPORTANCE The ubiquity, toxicity, and persistence of polybrominated diphenyl ethers (PBDEs) in the environment have drawn significant public and scientific interest to the need for the remediation of PBDE-contaminated ecosystems. However, the low bioavailability of PBDEs in environmental compartments typically limits bioremediation of PBDEs and has long impeded the study of anaerobic microbial PBDE removal. In the current study, a novel Dehalococcoides mccartyi strain, dubbed strain TZ50, that expresses RDases that mediate organohalide respiration of both PBDEs and chloroethenes was isolated and characterized. Strain TZ50 could potentially be used to remediate multiple cooccurring organohalides in contaminated systems.
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27
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Lumio RT, Tan MA, Magpantay HD. Biotechnology-based microbial degradation of plastic additives. 3 Biotech 2021; 11:350. [PMID: 34221820 PMCID: PMC8217394 DOI: 10.1007/s13205-021-02884-8] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2020] [Accepted: 06/06/2021] [Indexed: 10/21/2022] Open
Abstract
Plastic additives are agents responsible to the flame resistance, durability, microbial resistance, and flexibility of plastic products. High demand for production and use of plastic additives is associated with environmental accumulation and various health hazards. One of the suitable methods of depleting plastic additive in the environment is bioremediation as it offers cost-efficiency, convenience, and sustainability. Microbial activity is one of the effective ways of detoxifying various compounds as microorganisms can adapt in an environment with high prevalence of pollutants. The present review discusses the use and abundance of these plastic additives, their health-related risks, the microorganisms capable of degrading them, the proposed mechanism of biodegradation, and current innovations capable of improving the efficiency of bioremediation.
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Affiliation(s)
- Rob T. Lumio
- Chemistry Department, De La Salle University, 2401 Taft Avenue, 0922 Manila, Philippines
| | - Mario A. Tan
- The Graduate School, University of Santo Tomas, Manila, Philippines
- College of Science and Research Center for the Natural and Applied Sciences, University of Santo, Tomas, Manila, Philippines
| | - Hilbert D. Magpantay
- Chemistry Department, De La Salle University, 2401 Taft Avenue, 0922 Manila, Philippines
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28
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Li Y, Zhao HP, Zhu L. Iron Sulfide Enhanced the Dechlorination of Trichloroethene by Dehalococcoides mccartyi Strain 195. Front Microbiol 2021; 12:665281. [PMID: 34140942 PMCID: PMC8203822 DOI: 10.3389/fmicb.2021.665281] [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: 02/07/2021] [Accepted: 04/06/2021] [Indexed: 12/04/2022] Open
Abstract
Iron sulfide (FeS) nanoparticles have great potential in environmental remediation. Using the representative species Dehalococcoides mccartyi strain 195 (Dhc 195), the effect of FeS on trichloroethene (TCE) dechlorination was studied with hydrogen and acetate as the electron donor and carbon source, respectively. With the addition of 0.2 mM Fe2+ and S2–, the dechlorination rate of TCE was enhanced from 25.46 ± 1.15 to 37.84 ± 1.89 μmol⋅L–1⋅day–1 by the in situ formed FeS nanoparticles, as revealed through X-ray diffraction. Comparing the tceA gene copy numbers between with FeS and without FeS, real-time polymerase chain reaction (PCR) indicated that the abundance of the tceA gene increased from (2.83 ± 0.13) × 107 to (4.27 ± 0.21) × 108 copies/ml on day 12. The transcriptional activity of key genes involved in the electron transport chain was upregulated after the addition of FeS, including those responsible for the iron–sulfur cluster assembly protein gene (DET1632) and transmembrane transport of iron (DET1503, DET0685), cobalamin (DET0685, DET1139), and molybdenum (DET1161) genes. Meanwhile, the reverse transcription of tceA was increased approximately five times on the 12th day. These upregulations together suggested that the electron transport of D. mccartyi strain 195 was enhanced by FeS for apparent TCE dechlorination. Overall, the present study provided an eco-friendly and effective method to achieve high remediation efficiency for organohalide-polluted groundwater and soil.
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Affiliation(s)
- Yaru Li
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China.,Key Laboratory of Organic Pollution Process and Control, Zhejiang University, Hangzhou, China
| | - He-Ping Zhao
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China
| | - Lizhong Zhu
- College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, China.,Key Laboratory of Organic Pollution Process and Control, Zhejiang University, Hangzhou, China
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29
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Lu Q, Liu J, He H, Liang Z, Qiu R, Wang S. Waste activated sludge stimulates in situ microbial reductive dehalogenation of organohalide-contaminated soil. JOURNAL OF HAZARDOUS MATERIALS 2021; 411:125189. [PMID: 33858119 DOI: 10.1016/j.jhazmat.2021.125189] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2020] [Revised: 01/14/2021] [Accepted: 01/19/2021] [Indexed: 06/12/2023]
Abstract
Due to its enriched organic matter, nutrients and growth cofactors, as well as a diverse range of microorganisms, waste activated sludge (WAS) might be an ideal additive to stimulate organohalide respiration for in situ bioremediation of organohalide-contaminated sites. In this study, we investigated the biostimulation and bioaugmentation impacts of WAS-amendment on the performance and microbiome in tetrachloroethene (PCE) and polychlorinated biphenyls (PCBs) dechlorinating microcosms. Results demonstrated that WAS-amendment increased PCE- and PCBs-dechlorination rate as much as 6.06 and 10.67 folds, respectively. The presence of WAS provided a favorable growth niche for organohalide-respiring bacteria (OHRB), including redox mediation and generation of electron donors and carbon sources. Particularly for the PCE dechlorination, indigenous Geobacter and WAS-derived Dehalococcoides were identified to play key roles in PCE-to-dichloroethene (DCE) and DCE-to-ethene dechlorination, respectively. Similar biostimulation and bioaugmentation effects of WAS-amendment were observed on both PCE- and PCBs-dechlorination in three different soils, i.e., laterite, brown loam and paddy soil. Risk assessment suggested low potential ecological risk of WAS amendment in remediation of organohalide-contaminated soil. Overall, this study provided an economic and efficient strategy to stimulate the organohalide respiration-based bioremediation in field applications.
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Affiliation(s)
- Qihong Lu
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou 510275, China
| | - Jinting Liu
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou 510275, China
| | - Haozheng He
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou 510275, China
| | - Zhiwei Liang
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou 510275, China
| | - Rongliang Qiu
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou 510275, China; Guangdong Laboratory for Lingnan Modern Agriculture, College of Natural Resources and Environment, South China Agricultural University, Guangzhou 510642, China
| | - Shanquan Wang
- Environmental Microbiomics Research Center, School of Environmental Science and Engineering, Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Sun Yat-Sen University, Guangzhou 510275, China.
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30
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Wang Z, Peng Y, Li J, Liu J, Zhang Q, Li X, Zhang L. Rapid initiation and stable maintenance of municipal wastewater nitritation during the continuous flow anaerobic/oxic process with an ultra-low sludge retention time. WATER RESEARCH 2021; 197:117091. [PMID: 33857896 DOI: 10.1016/j.watres.2021.117091] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2020] [Revised: 03/20/2021] [Accepted: 03/23/2021] [Indexed: 05/06/2023]
Abstract
Rapid achievement of nitritation of mainstream municipal wastewater in a continuous-flow process is attractive since it favors the involvement of the anammox process and reduces the operational costs. In this study, a feasible and economical strategy is proposed to rapidly achieve the nitritation of municipal wastewater. By aggressively discharging excess sludge during the seasonal warming period (temperature increasing from 18°C to 22°C), nitritation was established in 15 days with a nitrite accumulation ratio of 85.09% in a continuous-flow anaerobic/oxic (An/O) reactor. Meanwhile, qPCR results revealed that amoA abundance increased from (1.78±0.10) × 108 copies/(g VSS) to (1.05±0.11) × 1010 copies/(g VSS) while the abundance of nitrite-oxidizing bacteria decreased from (1.1±0.02) × 1010 copies/(g VSS) to (5.01±0.02) × 108 copies/(g VSS). The temperature gradually stabilized at 26°C during the following operational period and stable nitritation was maintained with a nitrite accumulation ratio above 90%, which was mainly attributed to a short sludge retention time (SRT) of 4.3 days and a low dissolved oxygen of 0.86 ± 0.5 mg/L. Falling temperature negatively impacted the stability of nitritation, but nitritation could be restarted by aggressively discharging excess sludge during another temperature increase period. Overall, this study provides a feasible strategy to start-up nitritation that has great potential applications for municipal wastewater treatment.
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Affiliation(s)
- Zihao Wang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Jianwei Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Jinjin Liu
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Qiong Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Xiyao Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Liang Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China.
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Zainab SM, Junaid M, Xu N, Malik RN. Antibiotics and antibiotic resistant genes (ARGs) in groundwater: A global review on dissemination, sources, interactions, environmental and human health risks. WATER RESEARCH 2020; 187:116455. [PMID: 33032106 DOI: 10.1016/j.watres.2020.116455] [Citation(s) in RCA: 306] [Impact Index Per Article: 76.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Revised: 09/22/2020] [Accepted: 09/23/2020] [Indexed: 05/05/2023]
Abstract
The discovery and evolution of antibiotics for humans and animals are among the most significant milestones of the 20th century. However, antibiotics play a significant role in the induction and dissemination of antibiotic resistance genes (ARGs) in groundwater that has recently become the primary environmental concern. They are administrated to humans and animals on a large scale and are persistent in the environment. Long term impacts of antibiotics in the ecological environment are not still clearly understood, and their occurrence and consequences have become an important research topic worldwide. The hotspot reservoirs of antibiotics and ARGs include medical facilities, livestock farming, aquaculture, landfills, on-site sanitation systems, sewage, and wastewater treatment plants. Our meta-analysis demonstrated that antibiotics, including ciprofloxacin, sulfamethoxazole, erythromycin, and tetracycline were found at high concentrations while sulfonamide and tetracycline ARGs were more prevalent in groundwater. Moreover, the highest reported concentrations of targeted antibiotics were used to calculate hazard quotient (HQ) and risk quotient (RQ) in global groundwater bodies to estimate environmental and human health risks, respectively. Due to limited available ecotoxicity data, RQ and HQ can only be calculated for a few antibiotics in groundwater. The risk assessment of antibiotics demonstrated that antibiotics with their current groundwater levels pose no human health risks, whereas only ciprofloxacin, erythromycin, flumequine, and sulfamethoxazole revealed moderate to low risks to aquatic species. The occurrence of ARGs and antibiotic resistant bacteria (ARBs) in groundwater is also not likely to pose human health risk but consumption of groundwater contaminated with ARGs and ARBs might contribute to the development of antibiotic resistance in humans. The present review also sheds light on the relationship between ARGs, antibiotics, microbial communities, and environmental factors in groundwater, and reported a significant correlation between them. It also addresses prospects for future outlooks into further areas of relevant research.
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Affiliation(s)
- Syeda Maria Zainab
- Environmental Health Laboratory, Department of Environmental Sciences, Quaid-i-Azam University, Islamabad, Pakistan
| | - Muhammad Junaid
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China.
| | - Nan Xu
- Key Laboratory for Heavy Metal Pollution Control and Reutilization, School of Environment and Energy, Peking University Shenzhen Graduate School, Shenzhen 518055, China
| | - Riffat Naseem Malik
- Environmental Health Laboratory, Department of Environmental Sciences, Quaid-i-Azam University, Islamabad, Pakistan.
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