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Cimmino L, Duarte AG, Ni D, Ekundayo BE, Pereira IAC, Stahlberg H, Holliger C, Maillard J. Structure of a membrane-bound menaquinol:organohalide oxidoreductase. Nat Commun 2023; 14:7038. [PMID: 37923808 PMCID: PMC10624902 DOI: 10.1038/s41467-023-42927-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2023] [Accepted: 10/26/2023] [Indexed: 11/06/2023] Open
Abstract
Organohalide-respiring bacteria are key organisms for the bioremediation of soils and aquifers contaminated with halogenated organic compounds. The major players in this process are respiratory reductive dehalogenases, corrinoid enzymes that use organohalides as substrates and contribute to energy conservation. Here, we present the structure of a menaquinol:organohalide oxidoreductase obtained by cryo-EM. The membrane-bound protein was isolated from Desulfitobacterium hafniense strain TCE1 as a PceA2B2 complex catalysing the dechlorination of tetrachloroethene. Two catalytic PceA subunits are anchored to the membrane by two small integral membrane PceB subunits. The structure reveals two menaquinone molecules bound at the interface of the two different subunits, which are the starting point of a chain of redox cofactors for electron transfer to the active site. In this work, the structure elucidates how energy is conserved during organohalide respiration in menaquinone-dependent organohalide-respiring bacteria.
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Affiliation(s)
- Lorenzo Cimmino
- Laboratory for Environmental Biotechnology, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland
| | - Américo G Duarte
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade NOVA de Lisboa, Oeiras, Portugal
| | - Dongchun Ni
- Laboratory of Biological Electron Microscopy, Ecole Polytechnique Fédérale de Lausanne (EPFL), and Department of Fundamental Microbiology, University of Lausanne, Lausanne, Switzerland
| | - Babatunde E Ekundayo
- Laboratory of Biological Electron Microscopy, Ecole Polytechnique Fédérale de Lausanne (EPFL), and Department of Fundamental Microbiology, University of Lausanne, Lausanne, Switzerland
| | - Inês A C Pereira
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade NOVA de Lisboa, Oeiras, Portugal
| | - Henning Stahlberg
- Laboratory of Biological Electron Microscopy, Ecole Polytechnique Fédérale de Lausanne (EPFL), and Department of Fundamental Microbiology, University of Lausanne, Lausanne, Switzerland.
| | - Christof Holliger
- Laboratory for Environmental Biotechnology, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
| | - Julien Maillard
- Laboratory for Environmental Biotechnology, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne, Switzerland.
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Wang J, Wu S, Yang Q, Liu B, Yang M, Fei W, Tang Y, Zhang X. Effect of the degradation performance on carbon tetrachloride by anaerobic co-metabolism under different external energy sources. CHEMOSPHERE 2022; 308:136262. [PMID: 36055587 DOI: 10.1016/j.chemosphere.2022.136262] [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: 05/13/2022] [Revised: 07/22/2022] [Accepted: 08/27/2022] [Indexed: 06/15/2023]
Abstract
In this research, a comprehensive study was carried out on the removal of carbon tetrachloride (CT) in the anaerobic co-metabolism (ACM) reactor. The experiments showed that when the hydraulic retention time (HRT) was 36 h, pH was 7, and influent CT was 2.5mg/L, the average removal efficiency reached 82.45 ± 2.56% in the glucose co-metabolism substrate reactor, exhibiting a dramatic excellent difference in reaction performance from the other two reactors (p < 0.05) and a favorable tolerance on the CT shock loading. The content of extracellular polymeric substances (EPS) and volatile fatty acids (VFA) demonstrated that glucose could supply more energy to protect the microorganisms, which was the appropriate external energy source. Moreover, microbial community structure and biostatistics analysis demonstrated that Pseudomonas was the most important dechlorination bacteria in ACM reactors, which might via dehalogenation process mediate the transformation of CT. The succession of methanogenic bacteria further demonstrated that CT degradation using co-digestion require to destroy hydrogenotrophic methane generation pathway and the external energy substances could make up the lack of hydrogen in the treatment of CT. The change of intermediate products hinted that anaerobic dechlorination process of CT in an ACM reactor was a sequential dechlorination process, and major transformation products measured were CF. Overall, this study has improved our understanding of the roles of CT degradation process in ACM reactors.
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Affiliation(s)
- Jia Wang
- MOK Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), Beijing, 100083, PR China; Industrial Technology Office, Ministry of Environmental Protection Center for Foreign Cooperation, Beijing, 100035, PR China
| | - Shuangrong Wu
- School of Civil Engineering, Tangshan University, Tangshan, 063000, PR China
| | - Qi Yang
- MOK Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), Beijing, 100083, PR China.
| | - Bingyang Liu
- MOK Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), Beijing, 100083, PR China
| | - Ming Yang
- Industrial Technology Office, Ministry of Environmental Protection Center for Foreign Cooperation, Beijing, 100035, PR China
| | - WeiLiang Fei
- Industrial Technology Office, Ministry of Environmental Protection Center for Foreign Cooperation, Beijing, 100035, PR China
| | - Yandong Tang
- Industrial Technology Office, Ministry of Environmental Protection Center for Foreign Cooperation, Beijing, 100035, PR China
| | - XiaoLan Zhang
- Industrial Technology Office, Ministry of Environmental Protection Center for Foreign Cooperation, Beijing, 100035, PR China
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Hudari MSB, Richnow H, Vogt C, Nijenhuis I. Mini-review: effect of temperature on microbial reductive dehalogenation of chlorinated ethenes: a review. FEMS Microbiol Ecol 2022; 98:6638985. [PMID: 35810002 DOI: 10.1093/femsec/fiac081] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2022] [Revised: 06/30/2022] [Accepted: 07/07/2022] [Indexed: 11/13/2022] Open
Abstract
Temperature is a key factor affecting microbial activity and ecology. An increase in temperature generally increases rates of microbial processes up to a certain threshold, above which rates decline rapidly. In the subsurface, temperature of groundwater is usually stable and related to the annual average temperature at the surface. However, anthropogenic activities related to the use of the subsurface, e.g. for thermal heat management, foremost heat storage, will affect the temperature of groundwater locally. This mini-review intends to summarize the current knowledge on reductive dehalogenation activities of the chlorinated ethenes, common urban groundwater contaminants, at different temperatures. This includes an overview of activity and dehalogenation extent at different temperatures in laboratory isolates and enrichment cultures, the effect of shifts in temperature in micro- and mesocosm studies as well as observed biotransformation at different natural and induced temperatures at contaminated field sites. Furthermore, we address indirect effects on biotransformation, e.g. changes in fermentation, methanogenesis and sulfate reduction as competing or synergetic microbial processes. Finally, we address the current gaps in knowledge regarding bioremediation of chlorinated ethenes, microbial community shifts and bottlenecks for active combination with thermal energy storage, and necessities for bioaugmentation and/or natural re-populations after exposure to high temperature.
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Affiliation(s)
- Mohammad Sufian Bin Hudari
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research - UFZ, Permoserstrasse 15, 04318 Leipzig, Germany
| | - Hans Richnow
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research - UFZ, Permoserstrasse 15, 04318 Leipzig, Germany
| | - Carsten Vogt
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research - UFZ, Permoserstrasse 15, 04318 Leipzig, Germany
| | - Ivonne Nijenhuis
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research - UFZ, Permoserstrasse 15, 04318 Leipzig, Germany
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4
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Cimmino L, Schmid AW, Holliger C, Maillard J. Stoichiometry of the Gene Products From the Tetrachloroethene Reductive Dehalogenase Operon pceABCT. Front Microbiol 2022; 13:838026. [PMID: 35283847 PMCID: PMC8905343 DOI: 10.3389/fmicb.2022.838026] [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: 12/17/2021] [Accepted: 01/27/2022] [Indexed: 11/13/2022] Open
Abstract
Organohalide respiration (OHR) is a bacterial anaerobic process that uses halogenated compounds, e.g., tetrachloroethene (PCE), as terminal electron acceptors. Our model organisms are Dehalobacter restrictus strain PER-K23, an obligate OHR bacterium (OHRB), and Desulfitobacterium hafniense strain TCE1, a bacterium with a versatile metabolism. The key enzyme is the PCE reductive dehalogenase (PceA) that is encoded in the highly conserved gene cluster (pceABCT) in both above-mentioned strains, and in other Firmicutes OHRB. To date, the functions of PceA and PceT, a dedicated molecular chaperone for the maturation of PceA, are well defined. However, the role of PceB and PceC are still not elucidated. We present a multilevel study aiming at deciphering the stoichiometry of pceABCT individual gene products. The investigation was assessed at RNA level by reverse transcription and (quantitative) polymerase chain reaction, while at protein level, proteomic analyses based on parallel reaction monitoring were performed to quantify the Pce proteins in cell-free extracts as well as in soluble and membrane fractions of both strains using heavy-labeled reference peptides. At RNA level, our results confirmed the co-transcription of all pce genes, while the quantitative analysis revealed a relative stoichiometry of the gene transcripts of pceA, pceB, pceC, and pceT at ~ 1.0:3.0:0.1:0.1 in D. restrictus. This trend was not observed in D. hafniense strain TCE1, where no substantial difference was measured for the four genes. At proteomic level, an apparent 2:1 stoichiometry of PceA and PceB was obtained in the membrane fraction, and a low abundance of PceC in comparison to the other two proteins. In the soluble fraction, a 1:1 stoichiometry of PceA and PceT was identified. In summary, we show that the pce gene cluster is transcribed as an operon with, however, a level of transcription that differs for individual genes, an observation that could be explained by post-transcriptional events. Despite challenges in the quantification of integral membrane proteins such as PceB and PceC, the similar abundance of PceA and PceB invites to consider them as forming a membrane-bound PceA2B protein complex, which, in contrast to the proposed model, seems to be devoid of PceC.
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Affiliation(s)
- Lorenzo Cimmino
- Laboratory for Environmental Biotechnology, Institute for Environmental Engineering, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Adrien W Schmid
- Protein Core Facility, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Christof Holliger
- Laboratory for Environmental Biotechnology, Institute for Environmental Engineering, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Julien Maillard
- Laboratory for Environmental Biotechnology, Institute for Environmental Engineering, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
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Dell’Armi E, Rossi MM, Taverna L, Petrangeli Papini M, Zeppilli M. Evaluation of the Bioelectrochemical Approach and Different Electron Donors for Biological Trichloroethylene Reductive Dechlorination. TOXICS 2022; 10:37. [PMID: 35051079 PMCID: PMC8777833 DOI: 10.3390/toxics10010037] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2021] [Revised: 01/07/2022] [Accepted: 01/10/2022] [Indexed: 01/05/2023]
Abstract
Trichloroethylene (TCE) and more in general chlorinated aliphatic hydrocarbons (CAHs) can be removed from a contaminated matrix thanks to microorganisms able to perform the reductive dechlorination reaction (RD). Due to the lack of electron donors in the contaminated matrix, CAHs' reductive dechlorination can be stimulated by fermentable organic substrates, which slowly release molecular hydrogen through their fermentation. In this paper, three different electron donors constituted by lactate, hydrogen, and a biocathode of a bioelectrochemical cell have been studied in TCE dechlorination batch experiments. The batch reactors evaluated in terms of reductive dechlorination rate and utilization efficiency of the electron donor reported that the bio-electrochemical system (BES) showed a lower RD rate with respect of lactate reactor (51 ± 9 µeq/d compared to 98 ± 4 µeq/d), while the direct utilization of molecular hydrogen gave a significantly lower RD rate (19 ± 8 µeq/d), due to hydrogen low solubility in liquid media. The study also gives a comparative evaluation of the different electron donors showing the capability of the bioelectrochemical system to reach comparable efficiencies with a fermentable substrate without the use of other chemicals, 10.7 ± 3.3% for BES with respect of 3.5 ± 0.2% for the lactate-fed batch reactor. This study shows the BES capability of being an alternative at classic remediation approaches.
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Affiliation(s)
- Edoardo Dell’Armi
- Department of Chemistry, Sapienza University of Rome, Piazzale Aldo Moro 5, 00185 Rome, Italy; (M.M.R.); (L.T.); (M.P.P.); (M.Z.)
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Dell’Armi E, Zeppilli M, De Santis F, Petrangeli Papini M, Majone M. Control of Sulfate and Nitrate Reduction by Setting Hydraulic Retention Time and Applied Potential on a Membraneless Microbial Electrolysis Cell for Perchloroethylene Removal. ACS OMEGA 2021; 6:25211-25218. [PMID: 34632180 PMCID: PMC8495709 DOI: 10.1021/acsomega.1c03001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 08/02/2021] [Indexed: 05/15/2023]
Abstract
A membraneless microbial electrolysis cell (MEC) has been developed for perchloroethylene (PCE) removal through the reductive dechlorination reaction. The MEC consists of a tubular reactor of 8.24 L equipped with a graphite-granule working electrode which stimulates dechlorinating microorganisms while a graphite-granule cylindrical envelopment contained in a plastic mesh constituted the counter electrode of the MEC. Synthetic PCE-contaminated groundwater has been used as the feeding solution to test the nitrate and sulfate reduction reactions on the MEC performance at different hydraulic retention times (HRTs) (4.1, 1.8, and 1.2) and different cathodic potentials [-350, -450, and -650 mV vs standard hydrogen electrode (SHE)]. The HRT decrease from 4.1 to 1.8 d promoted a considerable increase in sulfate removal from 38 ± 11 to 113 ± 26 mg/Ld with a consequent current increase, while a shorter HRT of 1.2 d caused a partial inhibition of sulfate reduction with a consequent current decrease from -99 ± 3 to -52 ± 6 mA. Similarly, the cathodic potential investigation showed a direct correlation of current generation and sulfate removal in which the utilization of a cathodic potential of -350 mV versus SHE allowed for an 80% decrease in the sulfate removal rate with a consequent current decrease from -163 ± 7 to 41 ± 5 mA. The study showed the possibility to mitigate the energy consumption of the process by avoiding side reactions and current generation, through the selection of an appropriate HRT and applied cathodic potential.
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Affiliation(s)
- Edoardo Dell’Armi
- Department of Chemistry, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy
| | - Marco Zeppilli
- Department of Chemistry, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy
| | - Federica De Santis
- Department of Chemistry, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy
| | | | - Mauro Majone
- Department of Chemistry, Sapienza University of Rome, P.le Aldo Moro 5, 00185 Rome, Italy
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7
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Yoshikawa M, Zhang M, Kawabe Y, Katayama T. Effects of ferrous iron supplementation on reductive dechlorination of tetrachloroethene and on methanogenic microbial community. FEMS Microbiol Ecol 2021; 97:6274675. [PMID: 33979429 PMCID: PMC8139862 DOI: 10.1093/femsec/fiab069] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2021] [Accepted: 05/10/2021] [Indexed: 11/14/2022] Open
Abstract
Chloroethenes are common soil and groundwater pollutants. Their dechlorination is impacted by environmental factors, such as the presence of metal ions. We here investigated the effect of ferrous iron on bacterial reductive dechlorination of chloroethenes and on methanogen community. Reductive dechlorination of tetrachloroethene was assayed with a groundwater sample originally containing 6.3 × 103 copies mL−1 of Dehalococcoides 16S rRNA gene and 2 mg L−1 of iron. Supplementation with 28 mg L−1 of ferrous iron enhanced the reductive dechlorination of cis-dichloroethene (cis-DCE) and vinyl chloride in the presence of methanogens. The supplementation shortened the time required for complete dechlorination of 1 mg L−1 of tetrachloroethene to ethene and ethane from 84 to 49 d. Methanogens, such as Candidatus ‘Methanogranum’, Methanomethylovorans and Methanocorpusculum, were significantly more abundant in iron-supplemented cultures than in non-supplemented cultures (P < 0.01). Upon methanogen growth inhibition by 2-bromoethanesulfonate and in the absence of iron supplementation, cis-DCE was not dechlorinated. Further, iron supplementation induced 71.3% dechlorination of cis-DCE accompanied by an increase in Dehalococcoides 16S rRNA and dehalogenase vcrA gene copies but not dehalogenase tceA gene copies. These observations highlight the cooperative effect of iron and methanogens on the reductive dechlorination of chloroethenes by Dehalococcoides spp.
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Affiliation(s)
- Miho Yoshikawa
- Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1, Higashi, Tsukuba, Ibaraki 305-8567, Japan
| | - Ming Zhang
- Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1, Higashi, Tsukuba, Ibaraki 305-8567, Japan
| | - Yoshishige Kawabe
- Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1, Higashi, Tsukuba, Ibaraki 305-8567, Japan
| | - Taiki Katayama
- Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology (AIST), 1-1-1, Higashi, Tsukuba, Ibaraki 305-8567, Japan
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Metagenomic- and Cultivation-Based Exploration of Anaerobic Chloroform Biotransformation in Hypersaline Sediments as Natural Source of Chloromethanes. Microorganisms 2020; 8:microorganisms8050665. [PMID: 32370295 PMCID: PMC7284496 DOI: 10.3390/microorganisms8050665] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 04/22/2020] [Accepted: 04/29/2020] [Indexed: 01/23/2023] Open
Abstract
Chloroform (CF) is an environmental contaminant that can be naturally formed in various environments ranging from forest soils to salt lakes. Here we investigated CF removal potential in sediments obtained from hypersaline lakes in Western Australia. Reductive dechlorination of CF to dichloromethane (DCM) was observed in enrichment cultures derived from sediments of Lake Strawbridge, which has been reported as a natural source of CF. No CF removal was observed in abiotic control cultures without artificial electron donors, indicating biotic CF dechlorination in the enrichment cultures. Increasing vitamin B12 concentration from 0.04 to 4 µM in enrichment cultures enhanced CF removal and reduced DCM formation. In cultures amended with 4 µM vitamin B12 and 13C labelled CF, formation of 13CO2 was detected. Known organohalide-respiring bacteria and reductive dehalogenase genes were neither detected using quantitative PCR nor metagenomic analysis of the enrichment cultures. Rather, members of the order Clostridiales, known to co-metabolically transform CF to DCM and CO2, were detected. Accordingly, metagenome-assembled genomes of Clostridiales encoded enzymatic repertoires for the Wood-Ljungdahl pathway and cobalamin biosynthesis, which are known to be involved in fortuitous and nonspecific CF transformation. This study indicates that hypersaline lake microbiomes may act as a filter to reduce CF emission to the atmosphere.
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Dong H, Li L, Lu Y, Cheng Y, Wang Y, Ning Q, Wang B, Zhang L, Zeng G. Integration of nanoscale zero-valent iron and functional anaerobic bacteria for groundwater remediation: A review. ENVIRONMENT INTERNATIONAL 2019; 124:265-277. [PMID: 30660027 DOI: 10.1016/j.envint.2019.01.030] [Citation(s) in RCA: 89] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2018] [Revised: 01/10/2019] [Accepted: 01/10/2019] [Indexed: 06/09/2023]
Abstract
The technology of integrating nanoscale zero-valent iron (nZVI) and functional anaerobic bacteria has broad prospects for groundwater remediation. This review focuses on the interactions between nZVI and three kinds of functional anaerobic bacteria: organohalide-respiring bacteria (OHRB), sulfate reducing bacteria (SRB) and iron reducing bacteria (IRB), which are commonly used in the anaerobic bioremediation. The coupling effects of nZVI and the functional bacteria on the contaminant removal in the integrated system are summarized. Generally, nZVI could create a suitable living condition for the growth and activity of anaerobic bacteria. OHRB and SRB could synergistically degrade organic halides and remove heavy metals with nZVI, and IRB could reactive the passivated nZVI by reducing the iron (hydr)oxides on the surface of nZVI. Moreover, the roles of these anaerobic bacteria in contaminant removal coupling with nZVI and the degradation mechanisms are illustrated. In addition, this review also discusses the main factors influencing the removal efficiency of contaminants in the integrated treatment system, including nZVI species and dosage, inorganic ions, organic matters, pH, type of pollutants, temperature, and carbon/energy sources, etc. Among these factors, the nZVI species and dosage play a fundamental role due to the potential cytotoxicity of nZVI, which might exert a negative impact on the performance of this integrated system. Lastly, the future research needs are proposed to better understand this integrated technology and effectively apply it in groundwater remediation.
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Affiliation(s)
- Haoran Dong
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China.
| | - Long Li
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Yue Lu
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Yujun Cheng
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Yaoyao Wang
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Qin Ning
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Bin Wang
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Lihua Zhang
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
| | - Guangming Zeng
- College of Environmental Science and Engineering, Hunan University, Changsha, Hunan 410082, China; Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha, Hunan 410082, China
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10
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Dang H, Kanitkar YH, Stedtfeld RD, Hatzinger PB, Hashsham SA, Cupples AM. Abundance of Chlorinated Solvent and 1,4-Dioxane Degrading Microorganisms at Five Chlorinated Solvent Contaminated Sites Determined via Shotgun Sequencing. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:13914-13924. [PMID: 30427665 DOI: 10.1021/acs.est.8b04895] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Shotgun sequencing was used for the quantification of taxonomic and functional biomarkers associated with chlorinated solvent bioremediation in 20 groundwater samples (five sites), following bioaugmentation with SDC-9. The analysis determined the abundance of (1) genera associated with chlorinated solvent degradation, (2) reductive dehalogenase (RDases) genes, (3) genes associated with 1,4-dioxane removal, (4) genes associated with aerobic chlorinated solvent degradation, and (5) D. mccartyi genes associated with hydrogen and corrinoid metabolism. The taxonomic analysis revealed numerous genera previously linked to chlorinated solvent degradation, including Dehalococcoides, Desulfitobacterium, and Dehalogenimonas. The functional gene analysis indicated vcrA and tceA from D. mccartyi were the RDases with the highest relative abundance. Reads aligning with both aerobic and anaerobic biomarkers were observed across all sites. Aerobic solvent degradation genes, etnC or etnE, were detected in at least one sample from each site, as were pmoA and mmoX. The most abundant 1,4-dioxane biomarker detected was Methylosinus trichosporium OB3b mmoX. Reads aligning to thmA or Pseudonocardia were not found. The work illustrates the importance of shotgun sequencing to provide a more complete picture of the functional abilities of microbial communities. The approach is advantageous over current methods because an unlimited number of functional genes can be quantified.
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Affiliation(s)
- Hongyu Dang
- Department of Civil and Environmental Engineering , Michigan State University , East Lansing , Michigan 48824 , United States
| | - Yogendra H Kanitkar
- Department of Civil and Environmental Engineering , Michigan State University , East Lansing , Michigan 48824 , United States
| | - Robert D Stedtfeld
- Department of Civil and Environmental Engineering , Michigan State University , East Lansing , Michigan 48824 , United States
| | - Paul B Hatzinger
- APTIM , 17 Princess Road , Lawrenceville , New Jersey 08648 , United States
| | - Syed A Hashsham
- Department of Civil and Environmental Engineering , Michigan State University , East Lansing , Michigan 48824 , United States
- Center for Microbial Ecology , Michigan State University , East Lansing , Michigan 48824 , United States
| | - Alison M Cupples
- Department of Civil and Environmental Engineering , Michigan State University , East Lansing , Michigan 48824 , United States
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11
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Comensoli L, Maillard J, Kooli WM, Junier P, Joseph E. Soluble and solid iron reduction assays with Desulfitobacterium hafniense. Bio Protoc 2018; 8:e3002. [PMID: 34395795 DOI: 10.21769/bioprotoc.3002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 08/16/2018] [Accepted: 08/19/2018] [Indexed: 11/02/2022] Open
Abstract
There is a pressing need to develop sustainable and efficient methods to protect and stabilize iron objects. To develop a conservation-restoration method for corroded iron objects, this bio-protocol presents the steps to investigate reductive dissolution of ferric iron and biogenic production of stabilizing ferrous iron minerals in the strict anaerobe Desulfitobacterium hafniense (strains TCE1 and LBE). We investigated iron reduction using three different Fe(III) sources: Fe(III)-citrate (a soluble phase), akaganeite (solid iron phase), and corroded coupons. This protocol describes a method that combines spectrophotometric quantification of the complex Fe(II)-Ferrozine® with mineral characterization by scanning electron microscopy and Raman spectroscopy. These three methods allow assessing reductive dissolution of ferric iron and biogenic mineral production as a promising alternative for the development of an innovative sustainable method for the stabilization of corroded iron.
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Affiliation(s)
- Lucrezia Comensoli
- Laboratory of Microbiology, Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland.,Laboratory of Technologies for Heritage Materials, Institute of Chemistry, University of Neuchâtel, Neuchâtel, Switzerland
| | - Julien Maillard
- Laboratory for Environmental Biotechnology, ENAC-IIE-LBE, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Wafa M Kooli
- Laboratory of Microbiology, Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland.,Laboratory of Technologies for Heritage Materials, Institute of Chemistry, University of Neuchâtel, Neuchâtel, Switzerland
| | - Pilar Junier
- Laboratory of Microbiology, Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland
| | - Edith Joseph
- Laboratory of Technologies for Heritage Materials, Institute of Chemistry, University of Neuchâtel, Neuchâtel, Switzerland.,Haute Ecole Arc Conservation-Restauration, HES-SO, Neuchâtel, Switzerland
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12
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El-Sayed WS. Characterization of a Highly Enriched Microbial Consortium Reductively Dechlorinating 2,3-Dichlorophenol and 2,4,6-Trichlorophenol and the Corresponding cprA Genes from River Sediment. Pol J Microbiol 2018; 65:341-352. [PMID: 29334051 DOI: 10.5604/17331331.1215613] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Anaerobic reductive dechlorination of 2,3-dichlorophenol (2,3DCP) and 2,4,6-trichlorophenol (2,4,6TCP) was investigated in microcosms from River Nile sediment. A stable sediment-free anaerobic microbial consortium reductively dechlorinating 2,3DCP and 2,4,6TCP was established. Defined sediment-free cultures showing stable dechlorination were restricted to ortho chlorine when enriched with hydrogen as the electron donor, acetate as the carbon source, and either 2,3-DCP or 2,4,6-TCP as electron acceptors. When acetate, formate, or pyruvate were used as electron donors, dechlorination activity was lost. Only lactate can replace dihydrogen as an electron donor. However, the dechlorination potential was decreased after successive transfers. To reveal chlororespiring species, the microbial community structure of chlorophenol-reductive dechlorinating enrichment cultures was analyzed by PCR-denaturing gradient gel electrophoresis (DGGE) of 16S rRNA gene fragments. Eight dominant bacteria were detected in the dechlorinating microcosms including members of the genera Citrobacter, Geobacter, Pseudomonas, Desulfitobacterium, Desulfovibrio and Clostridium. Highly enriched dechlorinating cultures were dominated by four bacterial species belonging to the genera Pseudomonas, Desulfitobacterium, and Clostridium. Desulfitobacterium represented the major fraction in DGGE profiles indicating its importance in dechlorination activity, which was further confirmed by its absence resulting in complete loss of dechlorination. Reductive dechlorination was confirmed by the stoichiometric dechlorination of 2,3DCP and 2,4,6TCP to metabolites with less chloride groups and by the detection of chlorophenol RD cprA gene fragments in dechlorinating cultures. PCR amplified cprA gene fragments were cloned and sequenced and found to cluster with the cprA/pceA type genes of Dehalobacter restrictus.
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Affiliation(s)
- Wael S El-Sayed
- Biology Department, Faculty of Science, Taibah University, Almadinah Almunawarah, KSA; Microbiology Department, Faculty of Science, Ain Shams University, Cairo, Egypt
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13
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Buttet GF, Willemin MS, Hamelin R, Rupakula A, Maillard J. The Membrane-Bound C Subunit of Reductive Dehalogenases: Topology Analysis and Reconstitution of the FMN-Binding Domain of PceC. Front Microbiol 2018; 9:755. [PMID: 29740408 PMCID: PMC5928378 DOI: 10.3389/fmicb.2018.00755] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Accepted: 04/04/2018] [Indexed: 12/15/2022] Open
Abstract
Organohalide respiration (OHR) is the energy metabolism of anaerobic bacteria able to use halogenated organic compounds as terminal electron acceptors. While the terminal enzymes in OHR, so-called reductive dehalogenases, are well-characterized, the identity of proteins potentially involved in electron transfer to the terminal enzymes remains elusive. Among the accessory genes identified in OHR gene clusters, the C subunit (rdhC) could well code for the missing redox protein between the quinol pool and the reductive dehalogenase, although it was initially proposed to act as transcriptional regulator. RdhC sequences are characterized by the presence of multiple transmembrane segments, a flavin mononucleotide (FMN) binding motif and two conserved CX3CP motifs. Based on these features, we propose a curated selection of RdhC proteins identified in general sequence databases. Beside the Firmicutes from which RdhC sequences were initially identified, the identified sequences belong to three additional phyla, the Chloroflexi, the Proteobacteria, and the Bacteriodetes. The diversity of RdhC sequences mostly respects the phylogenetic distribution, suggesting that rdhC genes emerged relatively early in the evolution of the OHR metabolism. PceC, the C subunit of the tetrachloroethene (PCE) reductive dehalogenase is encoded by the conserved pceABCT gene cluster identified in Dehalobacter restrictus PER-K23 and in several strains of Desulfitobacterium hafniense. Surfaceome analysis of D. restrictus cells confirmed the predicted topology of the FMN-binding domain (FBD) of PceC that is the exocytoplasmic face of the membrane. Starting from inclusion bodies of a recombinant FBD protein, strategies for successful assembly of the FMN cofactor and refolding were achieved with the use of the flavin-trafficking protein from D. hafniense TCE1. Mass spectrometry analysis and site-directed mutagenesis of rFBD revealed that threonine-168 of PceC is binding FMN covalently. Our results suggest that PceC, and more generally RdhC proteins, may play a role in electron transfer in the metabolism of OHR.
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Affiliation(s)
- Géraldine F Buttet
- Laboratory for Environmental Biotechnology, Institute for Environmental Engineering, Swiss Federal Institute of Technology in Lausanne, Lausanne, Switzerland
| | - Mathilde S Willemin
- Laboratory for Environmental Biotechnology, Institute for Environmental Engineering, Swiss Federal Institute of Technology in Lausanne, Lausanne, Switzerland
| | - Romain Hamelin
- Protein Core Facility, Faculty of Life Sciences, Swiss Federal Institute of Technology in Lausanne, Lausanne, Switzerland
| | - Aamani Rupakula
- Laboratory for Environmental Biotechnology, Institute for Environmental Engineering, Swiss Federal Institute of Technology in Lausanne, Lausanne, Switzerland
| | - Julien Maillard
- Laboratory for Environmental Biotechnology, Institute for Environmental Engineering, Swiss Federal Institute of Technology in Lausanne, Lausanne, Switzerland
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14
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Kruse T, Goris T, Maillard J, Woyke T, Lechner U, de Vos W, Smidt H. Comparative genomics of the genus Desulfitobacterium. FEMS Microbiol Ecol 2017; 93:4443196. [DOI: 10.1093/femsec/fix135] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2017] [Accepted: 10/10/2017] [Indexed: 02/03/2023] Open
Affiliation(s)
- Thomas Kruse
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708 WE Wageningen, The Netherlands
| | - Tobias Goris
- Department of Applied and Ecological Microbiology, Friedrich-Schiller-University Jena, Philosophenweg 12, 07743 Jena, Germany
| | - Julien Maillard
- Laboratory for Environmental Biotechnology, ENAC-IIE-LBE, Ecole Polytechnique Fédérale de Lausanne (EPFL), Station 6, CH-1015 Lausanne, Switzerland
| | - Tanja Woyke
- U.S. Department of Energy Joint Genome Institute, Walnut Creek, CA 94598, USA
| | - Ute Lechner
- Institute of Biology/Microbiology, Martin-Luther-Universität Halle-Wittenberg, Kurt-Mothes-Str. 3, Halle 06120, Germany
| | - Willem de Vos
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708 WE Wageningen, The Netherlands
- Research Programme Unit Immunobiology, Department of Bacteriology and Immunology, Helsinki University, P.O. Box 21, 00014 Helsinki, Finland
| | - Hauke Smidt
- Laboratory of Microbiology, Wageningen University, Stippeneng 4, 6708 WE Wageningen, The Netherlands
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15
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Yoshikawa M, Zhang M, Toyota K. Biodegradation of Volatile Organic Compounds and Their Effects on Biodegradability under Co-Existing Conditions. Microbes Environ 2017; 32:188-200. [PMID: 28904262 PMCID: PMC5606688 DOI: 10.1264/jsme2.me16188] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Volatile organic compounds (VOCs) are major pollutants that are found in contaminated sites, particularly in developed countries such as Japan. Various microorganisms that degrade individual VOCs have been reported, and genomic information related to their phylogenetic classification and VOC-degrading enzymes is available. However, the biodegradation of multiple VOCs remains a challenging issue. Practical sites, such as chemical factories, research facilities, and illegal dumping sites, are often contaminated with multiple VOCs. In order to investigate the potential of biodegrading multiple VOCs, we initially reviewed the biodegradation of individual VOCs. VOCs include chlorinated ethenes (tetrachloroethene, trichloroethene, dichloroethene, and vinyl chloride), BTEX (benzene, toluene, ethylbenzene, and xylene), and chlorinated methanes (carbon tetrachloride, chloroform, and dichloromethane). We also summarized essential information on the biodegradation of each kind of VOC under aerobic and anaerobic conditions, together with the microorganisms that are involved in VOC-degrading pathways. Interactions among multiple VOCs were then discussed based on concrete examples. Under conditions in which multiple VOCs co-exist, the biodegradation of a VOC may be constrained, enhanced, and/or unaffected by other compounds. Co-metabolism may enhance the degradation of other VOCs. In contrast, constraints are imposed by the toxicity of co-existing VOCs and their by-products, catabolite repression, or competition between VOC-degrading enzymes. This review provides fundamental, but systematic information for designing strategies for the bioremediation of multiple VOCs, as well as information on the role of key microorganisms that degrade VOCs.
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Affiliation(s)
- Miho Yoshikawa
- Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology (AIST).,Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology
| | - Ming Zhang
- Geological Survey of Japan, National Institute of Advanced Industrial Science and Technology (AIST)
| | - Koki Toyota
- Graduate School of Bio-Applications and Systems Engineering, Tokyo University of Agriculture and Technology
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16
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Dolinová I, Štrojsová M, Černík M, Němeček J, Macháčková J, Ševců A. Microbial degradation of chloroethenes: a review. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:13262-13283. [PMID: 28378313 DOI: 10.1007/s11356-017-8867-y] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Accepted: 03/17/2017] [Indexed: 05/28/2023]
Abstract
Contamination by chloroethenes has a severe negative effect on both the environment and human health. This has prompted intensive remediation activity in recent years, along with research into the efficacy of natural microbial communities for degrading toxic chloroethenes into less harmful compounds. Microbial degradation of chloroethenes can take place either through anaerobic organohalide respiration, where chloroethenes serve as electron acceptors; anaerobic and aerobic metabolic degradation, where chloroethenes are used as electron donors; or anaerobic and aerobic co-metabolic degradation, with chloroethene degradation occurring as a by-product during microbial metabolism of other growth substrates, without energy or carbon benefit. Recent research has focused on optimising these natural processes to serve as effective bioremediation technologies, with particular emphasis on (a) the diversity and role of bacterial groups involved in dechlorination microbial processes, and (b) detection of bacterial enzymes and genes connected with dehalogenation activity. In this review, we summarise the different mechanisms of chloroethene bacterial degradation suitable for bioremediation and provide a list of dechlorinating bacteria. We also provide an up-to-date summary of primers available for detecting functional genes in anaerobic and aerobic bacteria degrading chloroethenes metabolically or co-metabolically.
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Affiliation(s)
- Iva Dolinová
- Institute for Nanomaterials, Advanced Technologies and Innovation, Technical University of Liberec, Studentská 2, 461 17, Liberec, Czech Republic
- Faculty of Mechatronics, Informatics and Interdisciplinary Studies, Technical University of Liberec, Studentská 2, 461 17, Liberec, Czech Republic
| | - Martina Štrojsová
- Institute for Nanomaterials, Advanced Technologies and Innovation, Technical University of Liberec, Studentská 2, 461 17, Liberec, Czech Republic
| | - Miroslav Černík
- Institute for Nanomaterials, Advanced Technologies and Innovation, Technical University of Liberec, Studentská 2, 461 17, Liberec, Czech Republic
- Faculty of Mechatronics, Informatics and Interdisciplinary Studies, Technical University of Liberec, Studentská 2, 461 17, Liberec, Czech Republic
| | - Jan Němeček
- Institute for Nanomaterials, Advanced Technologies and Innovation, Technical University of Liberec, Studentská 2, 461 17, Liberec, Czech Republic
| | - Jiřina Macháčková
- Institute for Nanomaterials, Advanced Technologies and Innovation, Technical University of Liberec, Studentská 2, 461 17, Liberec, Czech Republic
| | - Alena Ševců
- Institute for Nanomaterials, Advanced Technologies and Innovation, Technical University of Liberec, Studentská 2, 461 17, Liberec, Czech Republic.
- Faculty of Mechatronics, Informatics and Interdisciplinary Studies, Technical University of Liberec, Studentská 2, 461 17, Liberec, Czech Republic.
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17
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Use of Bacteria To Stabilize Archaeological Iron. Appl Environ Microbiol 2017; 83:AEM.03478-16. [PMID: 28283522 DOI: 10.1128/aem.03478-16] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Accepted: 02/15/2017] [Indexed: 11/20/2022] Open
Abstract
Iron artifacts are common among the findings of archaeological excavations. The corrosion layer formed on these objects requires stabilization after their recovery, without which the destruction of the item due to physicochemical damage is likely. Current technologies for stabilizing the corrosion layer are lengthy and generate hazardous waste products. Therefore, there is a pressing need for an alternative method for stabilizing the corrosion layer on iron objects. The aim of this study was to evaluate an alternative conservation-restoration method using bacteria. For this, anaerobic iron reduction leading to the formation of stable iron minerals in the presence of chlorine was investigated for two strains of Desulfitobacterium hafniense (strains TCE1 and LBE). Iron reduction was observed for soluble Fe(III) phases as well as for akaganeite, the most troublesome iron compound in the corrosion layer of archaeological iron objects. In terms of biogenic mineral production, differential efficiencies were observed in assays performed on corroded iron coupons. Strain TCE1 produced a homogeneous layer of vivianite covering 80% of the corroded surface, while on the coupons treated with strain LBE, only 10% of the surface was covered by the same mineral. Finally, an attempt to reduce iron on archaeological objects was performed with strain TCE1, which led to the formation of both biogenic vivianite and magnetite on the surface of the artifacts. These results demonstrate the potential of this biological treatment for stabilizing archaeological iron as a promising alternative to traditional conservation-restoration methods.IMPORTANCE Since the Iron Age, iron has been a fundamental material for the building of objects used in everyday life. However, due to its reactivity, iron can be easily corroded, and the physical stability of the object built is at risk. This is particularly true for archaeological objects on which a potentially unstable corrosion layer is formed during the time the object is buried. After excavation, changes in environmental conditions (e.g., higher oxygen concentration or lower humidity) alter the stability of the corrosion layer and can lead to the total destruction of the object. In this study, we demonstrate the feasibility of an innovative treatment based on bacterial iron reduction and biogenic mineral formation to stabilize the corrosion layer and protect these objects.
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18
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Anand S, Kaur H, Mande SS. Comparative In silico Analysis of Butyrate Production Pathways in Gut Commensals and Pathogens. Front Microbiol 2016; 7:1945. [PMID: 27994578 PMCID: PMC5133246 DOI: 10.3389/fmicb.2016.01945] [Citation(s) in RCA: 137] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2016] [Accepted: 11/18/2016] [Indexed: 12/22/2022] Open
Abstract
Biosynthesis of butyrate by commensal bacteria plays a crucial role in maintenance of human gut health while dysbiosis in gut microbiome has been linked to several enteric disorders. Contrastingly, butyrate shows cytotoxic effects in patients with oral diseases like periodontal infections and oral cancer. In addition to these host associations, few syntrophic bacteria couple butyrate degradation with sulfate reduction and methane production. Thus, it becomes imperative to understand the distribution of butyrate metabolism pathways and delineate differences in substrate utilization between pathogens and commensals. The bacteria utilize four pathways for butyrate production with different initial substrates (Pyruvate, 4-aminobutyrate, Glutarate and Lysine) which follow a polyphyletic distribution. A comprehensive mining of complete/draft bacterial genomes indicated conserved juxtaposed genomic arrangement in all these pathways. This gene context information was utilized for an accurate annotation of butyrate production pathways in bacterial genomes. Interestingly, our analysis showed that inspite of a beneficial impact of butyrate in gut, not only commensals, but a few gut pathogens also possess butyrogenic pathways. The results further illustrated that all the gut commensal bacteria (Faecalibacterium, Roseburia, Butyrivibrio, and commensal species of Clostridia etc) ferment pyruvate for butyrate production. On the contrary, the butyrogenic gut pathogen Fusobacterium utilizes different amino acid metabolism pathways like those for Glutamate (4-aminobutyrate and Glutarate) and Lysine for butyrogenesis which leads to a concomitant release of harmful by-products like ammonia in the process. The findings in this study indicate that commensals and pathogens in gut have divergently evolved to produce butyrate using distinct pathways. No such evolutionary selection was observed in oral pathogens (Porphyromonas and Filifactor) which showed presence of pyruvate as well as amino acid fermenting pathways which might be because the final product butyrate is itself known to be cytotoxic in oral diseases. This differential utilization of butyrogenic pathways in gut pathogens and commensals has an enormous ecological impact taking into consideration the immense influence of butyrate on different disorders in humans. The results of this study can potentially guide bioengineering experiments to design therapeutics/probiotics by manipulation of butyrate biosynthesis gene clusters in bacteria.
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Affiliation(s)
- Swadha Anand
- Bio-Sciences R&D Division, TCS Research, Tata Consultancy Services Ltd. Pune, India
| | - Harrisham Kaur
- Bio-Sciences R&D Division, TCS Research, Tata Consultancy Services Ltd. Pune, India
| | - Sharmila S Mande
- Bio-Sciences R&D Division, TCS Research, Tata Consultancy Services Ltd. Pune, India
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19
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Kim C, Ainala SK, Oh YK, Jeon BH, Park S, Kim JR. Metabolic flux change in Klebsiella pneumoniae L17 by anaerobic respiration in microbial fuel cell. BIOTECHNOL BIOPROC E 2016. [DOI: 10.1007/s12257-015-0777-6] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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20
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Bioremediation of Hydrocarbons and Chlorinated Solvents in Groundwater: Characterisation, Design and Performance Assessment. SPRINGER PROTOCOLS HANDBOOKS 2016. [DOI: 10.1007/8623_2016_207] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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21
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Jugder BE, Ertan H, Lee M, Manefield M, Marquis CP. Reductive Dehalogenases Come of Age in Biological Destruction of Organohalides. Trends Biotechnol 2015; 33:595-610. [DOI: 10.1016/j.tibtech.2015.07.004] [Citation(s) in RCA: 70] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2015] [Revised: 07/27/2015] [Accepted: 07/30/2015] [Indexed: 11/28/2022]
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22
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Velimirovic M, Simons Q, Bastiaens L. Use of CAH-degrading bacteria as test-organisms for evaluating the impact of fine zerovalent iron particles on the anaerobic subsurface environment. CHEMOSPHERE 2015; 134:338-345. [PMID: 25973858 DOI: 10.1016/j.chemosphere.2015.04.068] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2014] [Revised: 04/16/2015] [Accepted: 04/25/2015] [Indexed: 06/04/2023]
Abstract
The release of fine zerovalent iron (ZVI) particles in the environment after being introduced for in-situ treatment of compounds like chlorinated aliphatic hydrocarbons (CAHs) may raise questions toward environmental safety, especially for nanoscale materials. Classical single-species ecotoxicity tests do focus on aerobic conditions and are only relevant for the scenario when ZVI-particles reach surface water. Herein, we present an alternative approach where a CAH-degrading mixed bacterial culture was used as test-organisms relevant for the anaerobic subsurface. The impact of different ZVI particles on the bacterial culture was evaluated mainly by quantifying ATP, a reporter molecule giving a general indication of the microbial activity. These lab-scale batch tests were performed in liquid medium, without protecting and buffering aquifer material, as such representing worst-case scenario. The activity of the bacterial culture was negatively influenced by nanoscale zerovalent iron at doses as low as 0.05 g L(-1). On the other hand, concentrations up to 2 g L(-1) of several different types of microscale zerovalent iron (mZVI) particles stimulated the activity. However, very high doses of 15-30 g L(-1) of mZVI showed an inhibiting effect on the bacterial community. Negative effects of ZVIs were confirmed by H2 accumulation in the batch reactors and the absence of lactate consumption. Observed inhibition also corresponded to a pH increase above 7.5, explicable by ZVI corrosion that was found to be dose-dependent. The obtained results suggest that low doses of mZVIs will not show severe inhibition effects on the microbial community once used for in-situ treatment of CAHs.
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Affiliation(s)
- Milica Velimirovic
- Flemish Institute for Technological Research (VITO), Boeretang 200, 2400 Mol, Belgium; Department of Environmental Geosciences, University of Vienna, Althanstrasse, 14, 1090 Vienna, Austria
| | - Queenie Simons
- Flemish Institute for Technological Research (VITO), Boeretang 200, 2400 Mol, Belgium
| | - Leen Bastiaens
- Flemish Institute for Technological Research (VITO), Boeretang 200, 2400 Mol, Belgium.
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23
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Karataş S, Hasar H, Taşkan E, Özkaya B, Şahinkaya E. Bio-reduction of tetrachloroethen using a H2-based membrane biofilm reactor and community fingerprinting. WATER RESEARCH 2014; 58:21-28. [PMID: 24731873 DOI: 10.1016/j.watres.2014.03.053] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2014] [Revised: 03/18/2014] [Accepted: 03/19/2014] [Indexed: 06/03/2023]
Abstract
Chlorinated ethenes in drinking water could be reductively dechlorinated to non-toxic ethene by using a hydrogen based membrane biofilm reactor (H2-MBfR) under denitrifying conditions as it provides an appropriate environment for dechlorinating bacteria in biofilm communities. This study evaluates the reductive dechlorination of perchloroethene (PCE) to non-toxic ethene (ETH) and comparative community analysis of the biofilm grown on the gas permeable membrane fibers. For these purposes, three H2-MBfRs receiving three different chlorinated ethenes (PCE, TCE and DCE) were operated under different hydraulic retention times (HRTs) and H2 pressures. Among these reactors, the H2-MBfR fed with PCE (H2-MBfR 1) accomplished a complete dechlorination, whereas cis-DCE accumulated in the TCE receiving H2-MBfR 2 and no dechlorination was detected in the DCE receiving H2-MBfR 3. The results showed that 95% of PCE dechlorinated to ETH together with over 99.8% dechlorination efficiency. Nitrate was the preferred electron acceptor as the most of electrons generated from H2 oxidation used for denitrification and dechlorination started under nitrate deficient conditions at increased H2 pressures. PCR-DGGE analysis showed that Dehalococcoides were present in autotrophic biofilm community dechlorinating PCE to ethene, and RDase genes analysis revealed that pceA, tceA, bvcA and vcrA, responsible for complete dechlorination step, were available in Dehalococcoides strains.
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Affiliation(s)
| | - Halil Hasar
- Fırat University, Faculty of Engineering, Department of Environmental Engineering, 23119 Elazığ, Turkey.
| | - Ergin Taşkan
- Fırat University, Faculty of Engineering, Department of Environmental Engineering, 23119 Elazığ, Turkey.
| | - Bestamin Özkaya
- Yıldız Technical University, Department of Environmental Engineering, İstanbul, Turkey.
| | - Erkan Şahinkaya
- Istanbul Medeniyet University, Department of Bioengineering, İstanbul, Turkey.
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24
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Bælum J, Scheutz C, Chambon JC, Jensen CM, Brochmann RP, Dennis P, Laier T, Broholm MM, Bjerg PL, Binning PJ, Jacobsen CS. The impact of bioaugmentation on dechlorination kinetics and on microbial dechlorinating communities in subsurface clay till. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2014; 186:149-157. [PMID: 24374375 DOI: 10.1016/j.envpol.2013.11.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2013] [Revised: 11/09/2013] [Accepted: 11/18/2013] [Indexed: 06/03/2023]
Abstract
A molecular study on how the abundance of the dechlorinating culture KB-1 affects dechlorination rates in clay till is presented. DNA extracts showed changes in abundance of specific dechlorinators as well as their functional genes. Independently of the KB-1 added, the microbial dechlorinator abundance increased to the same level in all treatments. In the non-bioaugmented microcosms the reductive dehalogenase gene bvcA increased in abundance, but when KB-1 was added the related vcrA gene increased while bvcA genes did not increase. Modeling showed higher vinyl-chloride dechlorination rates and shorter time for complete dechlorination to ethene with higher initial concentration of KB-1 culture, while cis-dichloroethene dechlorination rates were not affected by KB-1 concentrations. This study provides high resolution abundance profiles of Dehalococcoides spp. (DHC) and functional genes, highlights the ecological behavior of KB-1 in clay till, and reinforces the importance of using multiple functional genes as biomarkers for reductive dechlorination.
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Affiliation(s)
- Jacob Bælum
- The Geological Survey of Denmark and Greenland (GEUS), Øster Voldgade 10, DK-1350 Copenhagen, Denmark; Technical University of Denmark (DTU), Novo Nordisk Foundation Center for Biosustainability, Fremtidsvej 3, DK-2970 Hørsholm, Denmark; The Technical University of Denmark (DTU), Center for Biological Sequence Analysis, Kemitorvet - Building 208, DK-2800 Kgs. Lyngby, Denmark
| | - Charlotte Scheutz
- The Technical University of Denmark (DTU), Department of Environmental Engineering, Miljøvej - Building 113, DK-2800 Kgs. Lyngby, Denmark
| | - Julie C Chambon
- The Technical University of Denmark (DTU), Department of Environmental Engineering, Miljøvej - Building 113, DK-2800 Kgs. Lyngby, Denmark
| | | | - Rikke P Brochmann
- The Geological Survey of Denmark and Greenland (GEUS), Øster Voldgade 10, DK-1350 Copenhagen, Denmark
| | - Philip Dennis
- SiREM, 130 Research Lane Suite 2, Guelph, ON N1G 5G3, Canada
| | - Troels Laier
- The Geological Survey of Denmark and Greenland (GEUS), Øster Voldgade 10, DK-1350 Copenhagen, Denmark
| | - Mette M Broholm
- The Technical University of Denmark (DTU), Department of Environmental Engineering, Miljøvej - Building 113, DK-2800 Kgs. Lyngby, Denmark
| | - Poul L Bjerg
- The Technical University of Denmark (DTU), Department of Environmental Engineering, Miljøvej - Building 113, DK-2800 Kgs. Lyngby, Denmark
| | - Philip J Binning
- The Technical University of Denmark (DTU), Department of Environmental Engineering, Miljøvej - Building 113, DK-2800 Kgs. Lyngby, Denmark
| | - Carsten S Jacobsen
- The Geological Survey of Denmark and Greenland (GEUS), Øster Voldgade 10, DK-1350 Copenhagen, Denmark; University of Copenhagen, Thorvaldsensvej 40, DK-1958 Frederiksberg C, Denmark; Center for Permafrost, Department of Geosciences and Natural Resource Management, University of Copenhagen, Øster Voldgade 10, DK-1350 Copenhagen, Denmark.
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Velimirovic M, Simons Q, Bastiaens L. Guar gum coupled microscale ZVI for in situ treatment of CAHs: continuous-flow column study. JOURNAL OF HAZARDOUS MATERIALS 2014; 265:20-29. [PMID: 24333711 DOI: 10.1016/j.jhazmat.2013.11.020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Revised: 11/07/2013] [Accepted: 11/10/2013] [Indexed: 06/03/2023]
Abstract
A column study was performed under in situ conditions to evaluate to which extend the inactivation of the microscale zerovalent iron (mZVI) by guar gum occurs under continuous flow conditions. Five aquifer containing columns were set up under different conditions. Efficient removal of trichloroethene was observed for the column amended by mZVI. Stabilization of the mZVI with guar gum led to slightly reduced activity. More reduced reactivity was observed in the poisoned column containing guar gum stabilized mZVI. This confirms that soil microorganisms can degrade guar gum and that subsequent removal of the oligosaccharides by the groundwater flow (flushing effect) can reactivate the mZVI. After more than six months of continuous operation the columns were dismantled. DNA-based qPCR analysis revealed that mZVI does not significantly affect the bacterial community, while guar gum stabilized mZVI particles can even induce bacterial growth. Overall, this study suggests that the temporarily decreased mZVI reactivity due to guar gum, has a rather limited impact on the performance of in situ reactive zones. The presence of guar gum slightly reduced the reactivity of iron, but also slowed down the iron corrosion rate which prolongs the life time of reactive zone.
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Affiliation(s)
- Milica Velimirovic
- Flemish Institute for Technological Research (VITO), Boeretang 200, 2400, Mol, Belgium; University of Antwerp, Department of Bio-Engineering, Groenenborgerlaan 171, 2020 Antwerp, Belgium.
| | - Queenie Simons
- Flemish Institute for Technological Research (VITO), Boeretang 200, 2400, Mol, Belgium.
| | - Leen Bastiaens
- Flemish Institute for Technological Research (VITO), Boeretang 200, 2400, Mol, Belgium.
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Futagami T, Fukaki Y, Fujihara H, Takegawa K, Goto M, Furukawa K. Evaluation of the inhibitory effects of chloroform on ortho-chlorophenol- and chloroethene-dechlorinating Desulfitobacterium strains. AMB Express 2013; 3:30. [PMID: 23705686 PMCID: PMC3679974 DOI: 10.1186/2191-0855-3-30] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2013] [Accepted: 05/21/2013] [Indexed: 01/22/2023] Open
Abstract
Organohalide-respiring Desulfitobacterium strains are believed to play an important role in the bioremediation and natural attenuation of chlorinated aliphatic and aromatic hydrocarbons. However, several studies have reported that chloroform significantly inhibits microbial reductive dechlorination of chloroethene. In this study, we examined the effect of chloroform on several Desulfitobacterium strains, including ortho-chlorophenol-dechlorinating Desulfitobacterium dehalogenans JW/IU-1 and Desulfitobacterium hafniense DCB-2, and also the chloroethene-dechlorinating strain D. hafniense TCE1. In medium containing 3-chloro-4-hydroxyphenylacetate as an electron acceptor, chloroform inhibited the growth of strains JW/IU-1 and DCB-2. Although chloroform did not directly inhibit dechlorination of 3-chloro-4-hydroxyphenylacetate by resting cells, cells cultivated with chloroform showed decreased dechlorination activity. Moreover, transcription of the gene encoding the reductive dehalogenase CprA decreased significantly in cells cultivated with chloroform. These results indicate that chloroform inhibits the growth and dechlorination activity of strains JW/IU-1 and DCB-2 via inhibition of cprA transcription. In contrast, cultivation of strain TCE1 in the presence of chloroform gave rise to a PceA reductive dehalogenase gene-deletion variant of strain TCE1; a similar phenomenon was observed in our previous study of chloroethene-dechlorinating D. hafniense strain Y51. Our results suggest that chloroform extensively inhibits the dechlorination activity of Desulfitobacterium strains, and that the inhibitory mechanism appears to differ between ortho-chlorophenol dechlorinators and chloroethene dechlorinators.
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Villemur R. The pentachlorophenol-dehalogenating Desulfitobacterium hafniense strain PCP-1. Philos Trans R Soc Lond B Biol Sci 2013; 368:20120319. [PMID: 23479749 DOI: 10.1098/rstb.2012.0319] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
In this report, a complete description of Desulfitobacterium hafniense strain PCP-1 is presented. The D. hafniense strain PCP-1 was isolated from a methanogenic consortium for its capacity to dehalogenate pentachlorophenol (PCP) into 3-chlorophenol. This strain is also capable of dehalogenating several other chloroaromatic compounds and tetrachloroethene into trichloroethene. Four gene loci encoding putative chlorophenol-reductive dehalogenases (CprA2 to CprA5) were detected, and the products of two of these loci have been demonstrated to dechlorinate different chlorinated phenols. Strain PCP-1 was used in laboratory-scale bioprocesses to degrade PCP present in contaminated environments. Desulfitobacterium hafniense PCP-1 is an excellent candidate for the development of efficient bioprocesses to degrade organohalide compounds.
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Affiliation(s)
- Richard Villemur
- INRS institut Armand-Frappier, 531 Boulevard des Prairies, Laval, Quebec, Canada, H7V 1B7.
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Lee PKH, Cheng D, West KA, Alvarez-Cohen L, He J. Isolation of two newDehalococcoides mccartyistrains with dissimilar dechlorination functions and their characterization by comparative genomics via microarray analysis. Environ Microbiol 2013; 15:2293-305. [DOI: 10.1111/1462-2920.12099] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2012] [Revised: 01/02/2013] [Accepted: 01/18/2013] [Indexed: 11/29/2022]
Affiliation(s)
| | - Dan Cheng
- Department of Civil and Environmental Engineering; National University of Singapore; Singapore; 117576
| | - Kimberlee A. West
- Department of Civil and Environmental Engineering; University of California; Berkeley; CA; 94720; USA
| | | | - Jianzhong He
- Department of Civil and Environmental Engineering; National University of Singapore; Singapore; 117576
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Berggren DRV, Marshall IPG, Azizian MF, Spormann AM, Semprini L. Effects of sulfate reduction on the bacterial community and kinetic parameters of a dechlorinating culture under chemostat growth conditions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:1879-86. [PMID: 23316874 DOI: 10.1021/es304244z] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
Results are presented from a chemostat study where the reductive dehalogenation of PCE was evaluated in the absence and presence of sulfate. Two chemostats inoculated with the Point Mugu culture, which contains strains of Dehalococcoides mccartyi, were operated at a 50 day HRT and fed PCE (1.12 mM) and lactate (4.3 mM). The control chemostat (PM-5L, no sulfate), achieved pseudo-steady-state transformation of PCE to ethene (98%) and VC (2%) at 2.4 nM of H(2). Batch kinetic tests with chemostat harvested cells showed the maximum rate (k(max)X) value for each dehalogenation step remained fairly constant, while hupL clone library analyses showed maintenance of a diverse D. mccartyi community. Sulfate (1 mM) was introduced to the second chemostat, PM-2L. Effective sulfate reduction was achieved 110 days later, resulting in 600 μM of total sulfide. PCE dechlorination efficiency decreased following complete sulfate reduction, yielding ethene (25%), VC (67%), and cis-DCE (8%). VC dechlorination was most affected, with k(max)X values decreasing by a factor of 50. The decrease was associated with the enrichment of the Cornell group of D. mccartyi and decline of the Pinellas group. Long-term exposure to sulfides and/or competition for H(2) may have been responsible for the community shift.
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Affiliation(s)
- Dusty R V Berggren
- School of Chemical, Biological and Environmental Engineering, 101 Gleeson Hall, Oregon State University , Corvallis, Oregon 97331, USA
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Chambon JC, Bjerg PL, Scheutz C, Baelum J, Jakobsen R, Binning PJ. Review of reactive kinetic models describing reductive dechlorination of chlorinated ethenes in soil and groundwater. Biotechnol Bioeng 2012; 110:1-23. [DOI: 10.1002/bit.24714] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2012] [Revised: 08/13/2012] [Accepted: 08/16/2012] [Indexed: 11/08/2022]
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Prat L, Maillard J, Rohrbach-Brandt E, Holliger C. An unusual tandem-domain rhodanese harbouring two active sites identified in Desulfitobacterium hafniense. FEBS J 2012; 279:2754-67. [PMID: 22686689 DOI: 10.1111/j.1742-4658.2012.08660.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The rhodanese protein domain is common throughout all kingdoms of life and is characterized by an active site cysteine residue that is able to bind sulfane sulfur and catalyse sulfur transfer. No unique function has been attributed to rhodanese-domain-containing proteins, most probably because of their diversity at both the level of sequence and protein domain architecture. In this study, we investigated the biochemical properties of an unusual rhodanese protein, PhsE, from Desulfitobacterium hafniense strain TCE1 which we have previously shown to be massively expressed under anaerobic respiration with tetrachloroethene. The peculiarity of the PhsE protein is its domain architecture which is constituted of two rhodanese domains each with an active site cysteine. The N-terminal rhodanese domain is preceded by a lipoprotein signal peptide anchoring PhsE on the outside of the cytoplasmic membrane. In vitro sulfur-transferase activity of recombinant PhsE variants was measured for both domains contrasting with other tandem-domain rhodaneses in which usually only the C-terminal domain has been found to be active. The genetic context of phsE shows that it is part of a six-gene operon displaying homology with gene clusters encoding respiratory molybdoenzymes of the PhsA/PsrA family, possibly involved in the reduction of sulfur compounds. Our data suggest, however, that the presence of sulfide in the medium is responsible for the high expression of PhsE in Desulfitobacterium, where it could play a role in the sulfur homeostasis of the cell.
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Affiliation(s)
- Laure Prat
- Laboratory for Environmental Biotechnology, Institute of Environmental Engineering, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
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The physiological opportunism of Desulfitobacterium hafniense strain TCE1 towards organohalide respiration with tetrachloroethene. Appl Environ Microbiol 2012; 78:6121-7. [PMID: 22729540 DOI: 10.1128/aem.01221-12] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Desulfitobacterium hafniense strain TCE1 is capable of metabolically reducing tetra- and trichloroethenes by organohalide respiration. A previous study revealed that the pce gene cluster responsible for this process is located on an active composite transposon, Tn-Dha1. In the present work, we investigated the effects on the stability of the transposon during successive subcultivations of strain TCE1 in a medium depleted of tetrachloroethene. At the physiological level, an increased fitness of the population was observed after 9 successive transfers and was correlated with a decrease in the level of production of the PceA enzyme. The latter observation was a result of the gradual loss of the pce genes in the population of strain TCE1 and not of a regulation mechanism, as was postulated previously for a similar phenomenon described for Sulfurospirillum multivorans. A detailed molecular analysis of genetic rearrangements occurring around Tn-Dha1 showed two independent but concomitant events, namely, the transposition of the first insertion sequence, ISDha1-a, and homologous recombination across identical copies of ISDha1 flanking the transposon. A new model is proposed for the genetic heterogeneity around Tn-Dha1 in D. hafniense strain TCE1, along with some considerations for the cleavage mechanism mediated by the transposase TnpA1 encoded by ISDha1.
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Genome sequence of Desulfitobacterium hafniense DCB-2, a Gram-positive anaerobe capable of dehalogenation and metal reduction. BMC Microbiol 2012; 12:21. [PMID: 22316246 PMCID: PMC3306737 DOI: 10.1186/1471-2180-12-21] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2011] [Accepted: 02/08/2012] [Indexed: 12/13/2022] Open
Abstract
Background The genome of the Gram-positive, metal-reducing, dehalorespiring Desulfitobacterium hafniense DCB-2 was sequenced in order to gain insights into its metabolic capacities, adaptive physiology, and regulatory machineries, and to compare with that of Desulfitobacterium hafniense Y51, the phylogenetically closest strain among the species with a sequenced genome. Results The genome of Desulfitobacterium hafniense DCB-2 is composed of a 5,279,134-bp circular chromosome with 5,042 predicted genes. Genome content and parallel physiological studies support the cell's ability to fix N2 and CO2, form spores and biofilms, reduce metals, and use a variety of electron acceptors in respiration, including halogenated organic compounds. The genome contained seven reductive dehalogenase genes and four nitrogenase gene homologs but lacked the Nar respiratory nitrate reductase system. The D. hafniense DCB-2 genome contained genes for 43 RNA polymerase sigma factors including 27 sigma-24 subunits, 59 two-component signal transduction systems, and about 730 transporter proteins. In addition, it contained genes for 53 molybdopterin-binding oxidoreductases, 19 flavoprotein paralogs of the fumarate reductase, and many other FAD/FMN-binding oxidoreductases, proving the cell's versatility in both adaptive and reductive capacities. Together with the ability to form spores, the presence of the CO2-fixing Wood-Ljungdahl pathway and the genes associated with oxygen tolerance add flexibility to the cell's options for survival under stress. Conclusions D. hafniense DCB-2's genome contains genes consistent with its abilities for dehalogenation, metal reduction, N2 and CO2 fixation, anaerobic respiration, oxygen tolerance, spore formation, and biofilm formation which make this organism a potential candidate for bioremediation at contaminated sites.
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Paterakis N, Chiu TY, Koh YKK, Lester JN, McAdam EJ, Scrimshaw MD, Soares A, Cartmell E. The effectiveness of anaerobic digestion in removing estrogens and nonylphenol ethoxylates. JOURNAL OF HAZARDOUS MATERIALS 2012; 199-200:88-95. [PMID: 22119197 DOI: 10.1016/j.jhazmat.2011.10.075] [Citation(s) in RCA: 55] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2011] [Revised: 10/17/2011] [Accepted: 10/22/2011] [Indexed: 05/20/2023]
Abstract
The fate and behaviour of two groups of endocrine disrupting chemicals, steroid estrogens and nonylphenol ethoxylates, have been evaluated during the anaerobic digestion of primary and mixed sewage sludge under mesophilic and thermophilic conditions. Digestion occurred over six retention times, in laboratory scale reactors, treating sludges collected from a sewage treatment works in the United Kingdom. It has been established that sludge concentrations of both groups of compounds demonstrated temporal variations and that concentrations in mixed sludge were influenced by the presence of waste activated sludge as a result of transformations during aerobic treatment. The biodegradation of total steroid estrogens was >50% during primary sludge digestion with lower removals observed for mixed sludge, which reflected bulk organic solids removal efficiencies. The removal of nonylphenol ethoxylates was greater in mixed sludge digestion (>58%) compared with primary sludge digestion and did not reflect bulk organic removal efficiencies. It is apparent that anaerobic digestion reduces the concentrations of these compounds, and would therefore be expected to confer a degree of protection against exposure and transfer of both groups of compounds to the receiving/re-use environment.
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Affiliation(s)
- N Paterakis
- Cranfield Water Science Institute, Cranfield University, Bedfordshire MK43 0AL, UK
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35
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Wang H, Lu L, Cui F, Liu D, Zhao Z, Xu Y. Simultaneous bioelectrochemical degradation of algae sludge and energy recovery in microbial fuel cells. RSC Adv 2012. [DOI: 10.1039/c2ra20631e] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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36
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Liang B, Jiang J, Zhang J, Zhao Y, Li S. Horizontal transfer of dehalogenase genes involved in the catalysis of chlorinated compounds: evidence and ecological role. Crit Rev Microbiol 2011; 38:95-110. [DOI: 10.3109/1040841x.2011.618114] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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37
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Zhang Y, Hu M, Jiang Z, Liu Y. Effect of anthraquinone-2,6-disulfonate on the trichloroethene degradation by Dehalococcoides-containing consortium. JOURNAL OF HAZARDOUS MATERIALS 2011; 192:1896-1899. [PMID: 21782334 DOI: 10.1016/j.jhazmat.2011.06.087] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2011] [Revised: 06/28/2011] [Accepted: 06/29/2011] [Indexed: 05/31/2023]
Abstract
This paper reports the findings of an examination on the influence of anthraquinone-2,6-disulfonate (AQDS) on the degradation of trichloroethene (TCE) by Dehalococcoides-containing consortium (designated UC-1). Compared with the control, the results indicated that (i) in 100 μmol/L AQDS, TCE was rapidly degraded. More ethene was produced, while less vinyl chloride (VC) was accumulated. AQDS might improve the activity of organisms in dechlorinating populations which resulted in more ethene being accumulated in the medium; (ii) in 500 μmol/L AQDS, TCE was incompletely degraded. Presumably, 500 μmol/L AQDS might have an inhibition effect on methanogens in the UC-1. The inhibition effect might influence the interactions among methanogens, Dehalococcoides species and other organisms in the UC-1.
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Affiliation(s)
- Ying Zhang
- School of Resources and Environment, Northeast Agricultural University, Harbin 150030, PR China.
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Wei N, Finneran KT. Influence of ferric iron on complete dechlorination of trichloroethylene (TCE) to ethene: Fe(III) reduction does not always inhibit complete dechlorination. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2011; 45:7422-7430. [PMID: 21777002 DOI: 10.1021/es201501a] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The effects of Fe(III) reduction on TCE, cis-DCE, and VC dechlorination were studied in both contaminated aquifer material and enrichment cultures. The results from sediment batch experiments demonstrated that Fe(III) reduction did not inhibit complete dechlorination. TCE was reduced concurrently with Fe(III) in the first 40 days of the incubations. While all incubations (plus and minus Fe(III)) generated approximately the same mass of ethene within the experimental time frame, Fe(III) speciation (ferrihydrite versus Fe(III)-NTA) had an impact on daughter product distribution and dechlorination kinetics. 16S rRNA gene clone library sequencing identified Dehalococcoides and Geobacteraceae as dominant populations, which included G. lovleyi like organisms. Quantitative PCR targeting 16S rRNA genes and Reductive Dehalogenase genes (tceA, bvcA, vcrA) indicated that Dehalococcoides and Geobacteraceae were enriched concurrently in the TCE-degrading, Fe(III)-reducing sediments. Enrichment cultures demonstrated that soluble Fe(III) had a greater impact on cis-DCE and VC reduction than solid-phase Fe(III). Geobacteraceae and Dehalococcoides were also coenriched in the liquid cultures, and the Dehalococcoides abundance in the presence of Fe(III) was not significantly different from those in the cultures without Fe(III). Hydrogen reached steady-state concentrations most amenable to complete dechlorination very quickly when Fe(III) was present in the culture, suggesting that Fe(III) reduction may actually help dechlorination. This was contrasted to hydrogen levels in nitrate-amended enrichments, in which hydrogen concentration was too low for any chlororespiration.
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Affiliation(s)
- Na Wei
- Environmental Engineering and Earth Sciences, Clemson University, 168 Rich Laboratory, Anderson, South Carolina 29625, United States
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Peng X, Yamamoto S, Vertès AA, Keresztes G, Inatomi KI, Inui M, Yukawa H. Global transcriptome analysis of the tetrachloroethene-dechlorinating bacterium Desulfitobacterium hafniense Y51 in the presence of various electron donors and terminal electron acceptors. J Ind Microbiol Biotechnol 2011; 39:255-68. [PMID: 21861158 DOI: 10.1007/s10295-011-1023-7] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2011] [Accepted: 07/24/2011] [Indexed: 11/24/2022]
Abstract
Desulfitobacterium hafniense Y51 is a dechlorinating bacterium that encodes an unusually large set of O-demethylase paralogs and specialized respiratory systems including specialized electron donors and acceptors. To use this organism in bioremediation of tetrachloroethene (PCE) or trichloroethene (TCE) pollution, expression patterns of its 5,060 genes were determined under different conditions using 60-mer probes in DNA microarrays. PCE, TCE, fumarate, nitrate, and dimethyl sulfoxide (DMSO) respiration all sustain the growth of strain Y51. Global transcriptome analyses were thus performed using various electron donor and acceptor couples (respectively, pyruvate and either fumarate, TCE, nitrate, or DMSO, and vanillate/fumarate). When TCE is used as terminal electron acceptor, resulting in its detoxification, a series of electron carriers comprising a cytochrome bd-type quinol oxidase (DSY4055-4056), a ferredoxin (DSY1451), and four Fe-S proteins (DSY1626, DSY1629, DSY0733, DSY3309) are upregulated, suggesting that the products of these genes are involved in PCE oxidoreduction. Interestingly, the PCE dehalogenase cluster (pceABCT) is constitutively expressed in the media tested, with pceT being upregulated and pceC downregulated in pyruvate/TCE-containing medium. In addition, another dehalogenation enzyme (DSY1155 coding for a putative chlorophenol reductive dehalogenase), is induced 225-fold in that medium, despite not being involved in PCE respiration. Remarkably since the reducing equivalents formed during pyruvate conversion to acetyl-CoA are channeled to electron acceptors including halogenated compounds, pyruvate induces expression of a pyruvate:ferredoxin oxidoreductase. This study paves the way to understanding the physiology of D. hafniense, optimizing this microbe as a bioremediation agent, and designing bioarray sensors to monitor the presence of dechlorinating organisms in the environment.
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Affiliation(s)
- Xue Peng
- Molecular Microbiology and Biotechnology Group, Research Institute of Innovative Technology for the Earth (RITE), 9-2 Kizugawadai, Kizugawa, Kyoto 619-0292, Japan
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Physiological adaptation of Desulfitobacterium hafniense strain TCE1 to tetrachloroethene respiration. Appl Environ Microbiol 2011; 77:3853-9. [PMID: 21478312 DOI: 10.1128/aem.02471-10] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Desulfitobacterium spp. are ubiquitous organisms with a broad metabolic versatility, and some isolates have the ability to use tetrachloroethene (PCE) as terminal electron acceptor. In order to identify proteins involved in this organohalide respiration process, a comparative proteomic analysis was performed. Soluble and membrane-associated proteins obtained from cells of Desulfitobacterium hafniense strain TCE1 that were growing on different combinations of the electron donors lactate and hydrogen and the electron acceptors PCE and fumarate were analyzed. Among proteins increasingly expressed in the presence of PCE compared to fumarate as electron acceptor, a total of 57 proteins were identified by mass spectrometry analysis, revealing proteins involved in stress response and associated regulation pathways, such as PspA, GroEL, and CodY, and also proteins potentially participating in carbon and energy metabolism, such as proteins of the Wood-Ljungdahl pathway and electron transfer flavoproteins. These proteomic results suggest that D. hafniense strain TCE1 adapts its physiology to face the relative unfavorable growth conditions during an apparent opportunistic organohalide respiration.
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Chang YC, Ikeutsu K, Toyama T, Choi D, Kikuchi S. Isolation and characterization of tetrachloroethylene- and cis-1,2-dichloroethylene-dechlorinating propionibacteria. J Ind Microbiol Biotechnol 2011; 38:1667-77. [DOI: 10.1007/s10295-011-0956-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2010] [Accepted: 03/05/2011] [Indexed: 11/28/2022]
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Frequent concomitant presence of Desulfitobacterium spp. and "Dehalococcoides" spp. in chloroethene-dechlorinating microbial communities. Appl Microbiol Biotechnol 2010; 90:361-8. [PMID: 21152914 DOI: 10.1007/s00253-010-3042-0] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2010] [Revised: 11/23/2010] [Accepted: 11/24/2010] [Indexed: 10/18/2022]
Abstract
The presence of chloroethene dechlorination activity as well as several bacterial genera containing mainly organohalide-respiring members was investigated in 34 environmental samples from 18 different sites. Cultures inoculated with these environmental samples on tetrachloroethene and amended weekly with a seven organic electron donor mixture resulted in 11 enrichments with cis-DCE, ten with VC, and 11 with ethene as dechlorination end product, and only two where no dechlorination was observed. "Dehalococcoides" spp. and Desulfitobacterium spp. were detected in the majority of the environmental samples independently of the dechlorination end product formed. The concomitant presence of Dehalococcoides spp. and Desulfitobacterium spp. in the majority of the enrichments suggested that chloroethene dechlorination was probably the result of catalysis by at least two organohalide-respiring genera either in parallel or by stepwise catalysis. A more detailed study of one enrichment on cis-DCE suggested that in this culture Desulfitobacterium spp. as well as Dehalococcoides spp. dechlorinated cis-DCE whereas dechlorination of VC was only catalyzed by the latter.
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Penny C, Vuilleumier S, Bringel F. Microbial degradation of tetrachloromethane: mechanisms and perspectives for bioremediation. FEMS Microbiol Ecol 2010; 74:257-75. [DOI: 10.1111/j.1574-6941.2010.00935.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
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46
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Okutman Tas D, Pavlostathis SG. Microbial transformation of pentachloronitrobenzene under nitrate reducing conditions. Biodegradation 2010; 21:691-702. [DOI: 10.1007/s10532-010-9335-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2009] [Accepted: 01/22/2010] [Indexed: 11/30/2022]
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Telke AA, Kalyani DC, Dawkar VV, Govindwar SP. Influence of organic and inorganic compounds on oxidoreductive decolorization of sulfonated azo dye C.I. Reactive Orange 16. JOURNAL OF HAZARDOUS MATERIALS 2009; 172:298-309. [PMID: 19640646 DOI: 10.1016/j.jhazmat.2009.07.008] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2009] [Revised: 06/23/2009] [Accepted: 07/01/2009] [Indexed: 05/28/2023]
Abstract
An isolated bacterial strain is placed in the branch of the Bacillus genus on the basis of 16S rRNA sequence and biochemical characteristics. It decolorized an individual and mixture of dyes, including reactive, disperse and direct. Bacillus sp. ADR showed 88% decolorization of sulfonated azo dye C.I. Reactive Orange 16 (100 mg L(-1)) with 2.62 mg of dye decolorized g(-1) dry cells h(-1) as specific decolorization rate along with 50% reduction in COD under static condition. The optimum pH and temperature for the decolorization was 7-8 and 30-40 degrees C, respectively. It was found to tolerate the sulfonated azo dye concentration up to 1.0 g L(-1). Significant induction in the activity of an extracellular phenol oxidase and NADH-DCIP reductase enzymes during decolorization of C.I. Reactive Orange 16 suggest their involvement in the decolorization. The metal salt (CaCl2), stabilizers (3,4-dimethoxy benzyl alcohol and o-tolidine) and electron donors (sodium acetate, sodium formate, sodium succinate, sodium citrate and sodium pyruvate) enhanced the C.I. Reactive Orange 16 decolorization rate of Bacillus sp. ADR. The 6-nitroso naphthol and dihydroperoxy benzene were final products obtained after decolorization of C.I. Reactive Orange 16 as characterized using FTIR and GC-MS.
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Affiliation(s)
- Amar A Telke
- Department of Biochemistry, Shivaji University, Kolhapur 416004, India
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Correlation of Dehalococcoides 16S rRNA and chloroethene-reductive dehalogenase genes with geochemical conditions in chloroethene-contaminated groundwater. Appl Environ Microbiol 2009; 76:843-50. [PMID: 20008170 DOI: 10.1128/aem.01482-09] [Citation(s) in RCA: 84] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Quantitative analysis of genes that code for Dehalococcoides 16S rRNA and chloroethene-reductive dehalogenases TceA, VcrA, and BvcA was done on groundwater sampled from 150 monitoring wells spread over 11 chlorinated ethene polluted European locations. Redundancy analysis was used to relate molecular data to geochemical conditions. Dehalococcoides 16S rRNA- and vinyl chloride (VC)-reductase genes were present at all tested locations in concentrations up to 10(6) gene copies per ml of groundwater. However, differences between and also within locations were observed. Variation in Dehalococcoides 16S rRNA gene copy numbers were most strongly correlated to dissolved organic carbon concentration in groundwater and to conditions appropriate for biodegradation of chlorinated ethenes (U.S. Environmental Protection Agency score). In contrast, vcrA gene copy numbers correlated most significantly to VC and chlorinated ethene concentrations. Interestingly, bvcA and especially tceA were more correlated with oxidizing conditions. In groundwater microcosms, dechlorination of 1 mM VC was correlated to an increase of vcrA and/or bvcA gene copies by 2 to 4 orders of magnitude. Interestingly, in 34% of the monitoring wells and in 40% of the active microcosms, the amount of individual VC-reductase gene copies exceeded that of Dehalococcoides 16S rRNA gene copies. It is concluded that the geographical distribution of the genes was not homogeneous, depending on the geochemical conditions, whereby tceA and bvcA correlated to more oxidized conditions than Dehalococcoides 16S rRNA and vcrA. Because the variation in VC-reductase gene numbers was not directly correlated to variation in Dehalococcoides spp., VC-reductase genes are better monitoring parameters for VC dechlorination capacity than Dehalococcoides spp.
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Popat SC, Deshusses MA. Reductive dehalogenation of trichloroethene vapors in an anaerobic biotrickling filter. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2009; 43:7856-7861. [PMID: 19921905 DOI: 10.1021/es901305x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Until now, it has not been possible to use biofiltration to treat trichloroethene (TCE) from waste gases generated by soil vapor extraction or dual-phase extraction at remediation sites because aerobic biodegradation of TCE is possible only via cometabolism, which is difficult to engineer on a large scale. This study looks at the possibility of conducting anaerobic gas-phase biotreatment of TCE vapors. The vision is that nitrogen sparging could be substituted for air sparging, resulting in TCE contaminated oxygen-free gas streams which require treatment A lab-scale anaerobic biotrickling filter inoculated with a mixed culture containing multiple Dehalococcoides strains was used for the proof of concept TCE vapors were removed via reductive dechlorination and converted to ethene, cis-1,2-dichloroethene (cis-DCE), and vinyl chloride (VC). Sodium lactate, a fermentable substrate, was provided to the reactor through the recirculating liquid as a source of hydrogen, the electron donor for Dehalococcoides strains. The biotrickling filter was able to remove >90% TCE at loadings of up to 4 g m(bed)(-3) h(-1) and sustained performance for over 200 days. The distribution of the intermediates of TCE biological reduction was found to be affected by the pH of the recirculating liquid. At pH 8.3, the primary accumulating productwas cis-DCE (approximately 92% of the TCE removed); while at pH 6.85-6.9, conversion to ethene, the intended end product, was 50-67% of the TCE removed. Kinetic determinations using batch biotrickling filter operation showed that VC reduction and not cis-DCE reduction was the sloweststep. Overall, the study shows that sustained anaerobic biotreatment of TCE vapors in biotrickling filters is possible.
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Affiliation(s)
- Sudeep C Popat
- Department of Chemical & Environmental Engineering, University of California, Riverside, California 92521, USA
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Protistan predation affects trichloroethene biodegradation in a bedrock aquifer. Appl Environ Microbiol 2009; 75:7588-93. [PMID: 19820148 DOI: 10.1128/aem.01820-09] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Despite extensive research on the bottom-up force of resource availability (e.g., electron donors and acceptors), slow biodegradation rates and stalling at cis-dichloroethene (cDCE) and vinyl chloride continue to be observed in aquifers contaminated with trichloroethene (TCE). The objective of this research was to gauge the impact of the top-down force of protistan predation on TCE biodegradation in laboratory microcosms. When indigenous bacteria from an electron donor-limited TCE-contaminated bedrock aquifer were present, the indigenous protists inhibited reductive dechlorination altogether. The presence of protists during organic carbon-amended conditions caused the bacteria to elongate (length:width, > or =10:1), but reductive dechlorination was still inhibited. When a commercially available dechlorinating bacterial culture and an organic carbon amendment were added in he presence of protists, the elongated bacteria predominated and reductive dechlorination stalled at cDCE. When protists were removed under organic carbon-amended conditions, reductive dechlorination stalled at cDCE, whereas in the presence organic carbon and bacterial amendments, the total chlorinated ethene concentration decreased, indicating TCE was converted to ethene and/or CO2. The data suggested that indigenous protists grazed dechlorinators to extremely low levels, inhibiting dechlorination altogether. Hence, in situ bioremediation/bioaugmentation may not be successful in mineralizing TCE unless the top-down force of protistan predation is inhibited.
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