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Chen S, Peng L, Xu Y, Wang N, Wang X, Liang C, Song K, Zhou Y. Modeling Free Nitrous Acid Inhibition on the Removal of Nitrogen and Atenolol during Sidestream Partial Nitritation Processes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:5162-5173. [PMID: 38358933 DOI: 10.1021/acs.est.3c10107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/17/2024]
Abstract
Sidestream serves as an important reservoir collecting pharmaceuticals from sludge. However, the knowledge on sidestream pharmaceutical removal is still insufficient. In this work, atenolol biodegradation during sidestream partial nitritation (PN) processes characterized by high free nitrous acid (FNA) accumulation was modeled. To describe the FNA inhibition on ammonia oxidation and atenolol removal, Vadivelu-type and Hellinga-type inhibition kinetics were introduced into the model framework. Four inhibitory parameters along with four biodegradation kinetic parameters were calibrated and validated separately with eight sets of batch experimental data and 60 days' PN reactor operational data. The developed model could accurately reproduce the dynamics of nitrogen and atenolol. The model prediction further revealed that atenolol biodegradation efficiencies by ammonia-oxidizing bacteria (AOB)-induced cometabolism, AOB-induced metabolism, and heterotrophic bacteria-induced biodegradation were 0, ∼ 60, and ∼35% in the absence of ammonium and FNA; ∼ 14, ∼ 29, and ∼28% at 0.03 mg-N L-1 FNA; and 7, 15, and 5% at 0.19 mg-N L-1 FNA. Model simulation showed that the nitritation efficiency of ∼99% and atenolol removal efficiency of 57.5% in the PN process could be achieved simultaneously by controlling pH at 8.5, while 89.2% total nitrogen and 57.1% atenolol were removed to the maximum at pH of 7.0 in PN coupling with the anammox process. The pH-based operational strategy to regulate FNA levels was mathematically demonstrated to be effective for achieving the simultaneous removal of nitrogen and atenolol in PN-based sidestream processes.
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Affiliation(s)
- Shi Chen
- Hubei Key Laboratory of Mineral Resources Processing and Environment, Wuhan University of Technology, Luoshi Road 122, Wuhan 430070, China
- School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan 430070, China
| | - Lai Peng
- Hubei Key Laboratory of Mineral Resources Processing and Environment, Wuhan University of Technology, Luoshi Road 122, Wuhan 430070, China
- School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan 430070, China
| | - Yifeng Xu
- Hubei Key Laboratory of Mineral Resources Processing and Environment, Wuhan University of Technology, Luoshi Road 122, Wuhan 430070, China
- School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan 430070, China
| | - Ning Wang
- Hubei Key Laboratory of Mineral Resources Processing and Environment, Wuhan University of Technology, Luoshi Road 122, Wuhan 430070, China
- School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan 430070, China
| | - Xi Wang
- Hubei Key Laboratory of Mineral Resources Processing and Environment, Wuhan University of Technology, Luoshi Road 122, Wuhan 430070, China
- School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan 430070, China
| | - Chuanzhou Liang
- Hubei Key Laboratory of Mineral Resources Processing and Environment, Wuhan University of Technology, Luoshi Road 122, Wuhan 430070, China
- School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan 430070, China
| | - Kang Song
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei 430072, China
| | - Yan Zhou
- School of Civil and Environmental Engineering, Nanyang Technological University, Singapore 639798, Singapore
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Willmann A, Tiehm A. Aerobic co-metabolic cis-Dichloroethene degradation with Trichloroethene as primary substrate and effects of concentration ratios. CHEMOSPHERE 2024; 350:141000. [PMID: 38135124 DOI: 10.1016/j.chemosphere.2023.141000] [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: 07/20/2023] [Revised: 12/12/2023] [Accepted: 12/19/2023] [Indexed: 12/24/2023]
Abstract
Pollution with chloroethenes threaten groundwater resources worldwide. Cis-Dichloroethene (cDCE) and Trichloroethene (TCE) are widespread pollutants that often occur together at contaminated sites, either as primary discharges or as degradation products of anaerobic dechlorination. In this study, comprehensive microcosm experiments were conducted with groundwater samples of seven sites contaminated with chloroethenes. In total, twelve wells with different pollutant concentrations and chloroethene compositions were sampled, and aerobic microcosms including sterile controls were set up. The results revealed interactions as well as interferences between cDCE and TCE. First, co-metabolic cDCE degradation with TCE as growth substrate was detected for the first time in this work. Transformation yields Ty' (molar ratio of co-substrate degraded to primary substrate degraded) of the degradation process were determined and showed a linear relationship with the cDCE/TCE concentration ratio. At low cDCE/TCE ratio, aerobic metabolic TCE degradation can result in complete cDCE removal due to co-metabolic degradation. Secondly, interfering effects were detected at notable cDCE levels resulting in deceleration of TCE degradation and residual concentrations which were also correlating linearly with the cDCE/TCE concentration ratio. These findings are significant for investigating chloroethene contaminated sites and planning remediation strategies. In particular, the efficiency biological remediation methods in the presence of both pollutants can be evaluated more precisely through the knowledge of interactions and interferences. Our study emphasizes that co-contaminants and possible effects of contaminant mixtures on the degradation rates of individual substances should be considered in general.
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Affiliation(s)
- Anna Willmann
- Department of Water Microbiology TZW: DVGW-Technologiezentrum Wasser, Karlsruher Straße 84, 76139, Karlsruhe, Germany; Working Group Environmental Mineralogy & Environmental System Analysis of the Institute of Applied Geosciences, Karlsruhe Institute of Technology, Adenauerring 20b, 76131, Karlsruhe, Germany
| | - Andreas Tiehm
- Department of Water Microbiology TZW: DVGW-Technologiezentrum Wasser, Karlsruher Straße 84, 76139, Karlsruhe, Germany.
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Puigserver D, Herrero J, Nogueras X, Cortés A, Parker BL, Playà E, Carmona JM. Biotic and abiotic reductive dechlorination of chloroethenes in aquitards. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 816:151532. [PMID: 34752872 DOI: 10.1016/j.scitotenv.2021.151532] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2021] [Revised: 11/03/2021] [Accepted: 11/04/2021] [Indexed: 06/13/2023]
Abstract
Chlorinated solvents occur as dense nonaqueous phase liquid (DNAPL) or as solutes when dissolved in water. They are present in many pollution sites in urban and industrial areas. They are toxic, carcinogenic, and highly recalcitrant in aquifers and aquitards. In the latter case, they migrate by molecular diffusion into the matrix. When aquitards are fractured, chlorinated solvents also penetrate as a free phase through the fractures. The main objective of this study was to analyze the biogeochemical processes occurring inside the matrix surrounding fractures and in the joint-points zones. The broader implications of this objective derive from the fact that, incomplete natural degradation of contaminants in aquitards generates accumulation of daughter products. This causes steep concentration gradients and back-diffusion fluxes between aquitards and high hydraulic conductivity layers. This offers opportunities to develop remediation strategies based, for example, on the coupling of biotic and reactive abiotic processes. The main results showed: 1) Degradation occurred especially in the matrix adjacent to the orthogonal network of fractures and textural heterogeneities, where texture contrasts favored microbial development because these zones constituted ecotones. 2) A dechlorinating bacterium not belonging to the Dehalococcoides genus, namely Propionibacterium acnes, survived under the high concentrations of dissolved perchloroethene (PCE) in contact with the PCE-DNAPL and was able to degrade it to trichloroethene (TCE). Dehalococcoides genus was able to conduct PCE reductive dechlorination at least up to cis-1,2-dichloroethene (cDCE), which shows again the potential of the medium to degrade chloroethenes in aquitards. 3) Degradation of PCE in the matrix resulted from the coupling of reactive abiotic and biotic processes-in the first case, promoted by Fe2+ sorbed to iron oxides, and in the latter case, related to dechlorinating microorganisms. The dechlorination resulting from these coupling processes is slow and limited by the need for an adequate supply of electron donors.
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Affiliation(s)
- Diana Puigserver
- Department of Mineralogy, Petrology and Applied Geology, Faculty of Earth Sciences, University of Barcelona (UB), Water Research Institute (IdRA-UB), Serra Húnter Tenure-elegible Lecturer, C/ Martí i Franquès, s/n, E-08028 Barcelona, Spain.
| | - Jofre Herrero
- Department of Mineralogy, Petrology and Applied Geology, Faculty of Earth Sciences, University of Barcelona (UB), Water Research Institute (IdRA-UB). C/ Martí i Franquès, s/n, E-08028 Barcelona, Spain.
| | - Xènia Nogueras
- Department of Mineralogy, Petrology and Applied Geology, Faculty of Earth Sciences, University of Barcelona (UB). C/ Martí i Franquès, s/n, E-08028 Barcelona, Spain; Health Section of the City Council of Mataró (Barcelona), Specialized Support Technician, Carrer de la Riera, 48, 08301 Mataró, Barcelona, Spain.
| | - Amparo Cortés
- Department of Biology, Health and Environment, Faculty of Pharmacy, University of Barcelona, Av. Joan XXIII, 27-31, E-08028 Barcelona, Spain.
| | - Beth L Parker
- School of Engineering, University of Guelph, 50, Stone Road East, Guelph, N1G 2W1, Ontario, Canada.
| | - E Playà
- Department of Mineralogy, Petrology and Applied Geology, Faculty of Earth Sciences, University of Barcelona (UB). C/ Martí i Franquès, s/n, E-08028 Barcelona, Spain.
| | - José M Carmona
- Department of Mineralogy, Petrology and Applied Geology, Faculty of Earth Sciences, University of Barcelona (UB), Water Research Institute (IdRA-UB). C/ Martí i Franquès, s/n, E-08028 Barcelona, Spain.
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Herrero J, Puigserver D, Nijenhuis I, Kuntze K, Parker BL, Carmona JM. The role of ecotones in the dehalogenation of chloroethenes in alluvial fan aquifers. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:26871-26884. [PMID: 33495954 DOI: 10.1007/s11356-021-12538-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Accepted: 01/13/2021] [Indexed: 05/20/2023]
Abstract
The presence of ecotones in transition zones between geological strata (e.g. layers of gravel and sand interbedded with layers of silt in distal alluvial fan deposits) in aquifers plays a significant role in regulating the flux of matter and energy between compartments. Ecotones are characterised by steep physicochemical and biological gradients and considerable biological diversity. However, the link between organic pollutants and degradation potential in ecotones has scarcely been studied. The aim of this study is to relate the presence of ecotones with the dehalogenation of chloroethenes. A field site was selected where chloroethene contamination occurs in a granular aquifer with geological heterogeneities. The site is monitored by multilevel and conventional wells. Groundwater samples were analysed by chemical, isotopic, and molecular techniques. The main results were as follows: (1) two ecotones were characterised in the source area, one in the upper part of the aquifer and the second in the transition zone to the bottom aquitard, where the aged pool is located; (2) the ecotone located in the transition zone to the bottom aquitard has greater microbial diversity, due to higher geological heterogeneities; (3) both ecotones show the reductive dehalogenation of perchloroethylene and trichloroethylene; and (4) these ecotones are the main zones of the reductive dehalogenation of the pollutants, given the more reductive conditions at the centre of the plume. These findings suggest that ecotones are responsible for natural attenuation, where oxic conditions prevailed at the aquifer and bioremediation strategies could be applied more effectively in these zones to promote complete reductive dehalogenation.
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Affiliation(s)
- Jofre Herrero
- Department of Minerology, Petrology and Applied Geology, Faculty of Earth Sciences, The Water Research Institute (IdRA), University of Barcelona, C/ Martí Franquès sn, Barcelona, Spain.
| | - Diana Puigserver
- Serra Húnter Tenure-elegible Lecturer, Department of Minerology, Petrology and Applied Geology, Faculty of Earth Sciences, The Water Research Institute (IdRA), University of Barcelona, C/ Martí Franquès sn, Barcelona, Spain
| | - Ivonne Nijenhuis
- Department of Isotope Biogeochemistry (ISOBIO), UFZ Centre for Environmental Research Leipzig-Halle, Permoserstr. 15, 04318, Leipzig, Germany
| | - Kevin Kuntze
- Department of Isotope Biogeochemistry (ISOBIO), UFZ Centre for Environmental Research Leipzig-Halle, Permoserstr. 15, 04318, Leipzig, Germany
- Isodetect, Deutscher Platz 5b, 04103, Leipzig, Germany
| | - Beth L Parker
- School of Engineering, University of Guelph 50, Stone Road East, Guelph, Ontario, N1G 2W1, Canada
| | - José M Carmona
- Department of Minerology, Petrology and Applied Geology, Faculty of Earth Sciences, The Water Research Institute (IdRA), University of Barcelona, C/ Martí Franquès sn, Barcelona, Spain
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Nsenga Kumwimba M, Meng F. Roles of ammonia-oxidizing bacteria in improving metabolism and cometabolism of trace organic chemicals in biological wastewater treatment processes: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 659:419-441. [PMID: 31096373 DOI: 10.1016/j.scitotenv.2018.12.236] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2018] [Revised: 11/20/2018] [Accepted: 12/15/2018] [Indexed: 05/27/2023]
Abstract
While there has been a significant recent improvement in the removal of pollutants in natural and engineered systems, trace organic chemicals (TrOCs) are posing a major threat to aquatic environments and human health. There is a critical need for developing potential strategies that aim at enhancing metabolism and/or cometabolism of these compounds. Recently, knowledge regarding biodegradation of TrOCs by ammonia-oxidizing bacteria (AOB) has been widely developed. This review aims to delineate an up-to-date version of the ecophysiology of AOB and outline current knowledge related to biodegradation efficiencies of the frequently reported TrOCs by AOB. The paper also provides an insight into biodegradation pathways by AOB and transformation products of these compounds and makes recommendations for future research of AOB. In brief, nitrifying WWTFs (wastewater treatment facilities) were superior in degrading most TrOCs than non-nitrifying WWTFs due to cometabolic biodegradation by the AOB. To fully understand and/or enhance the cometabolic biodegradation of TrOCs by AOB, recent molecular research has focused on numerous crucial factors including availability of the compounds to AOB, presence of growth substrate (NH4-N), redox potentials, microorganism diversity (AOB and heterotrophs), physicochemical properties and operational parameters of the WWTFs, molecular structure of target TrOCs and membrane-based technologies, may all significantly impact the cometabolic biodegradation of TrOCs. Still, further exploration is required to elucidate the mechanisms involved in biodegradation of TrOCs by AOB and the toxicity levels of formed products.
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Affiliation(s)
- Mathieu Nsenga Kumwimba
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, PR China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, PR China; Faculty of Agronomy, Department of Natural Resources and Environmental Management, University of Lubumbashi, Democratic Republic of the Congo
| | - Fangang Meng
- School of Environmental Science and Engineering, Sun Yat-sen University, Guangzhou 510275, PR China; Guangdong Provincial Key Laboratory of Environmental Pollution Control and Remediation Technology, Sun Yat-sen University, Guangzhou 510275, PR China.
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6
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Yuan K, Xie X, Wang X, Lin L, Yang L, Luan T, Chen B. Transcriptional response of Mycobacterium sp. strain A1-PYR to multiple polycyclic aromatic hydrocarbon contaminations. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2018; 243:824-832. [PMID: 30243191 DOI: 10.1016/j.envpol.2018.09.001] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/25/2018] [Revised: 08/29/2018] [Accepted: 09/01/2018] [Indexed: 06/08/2023]
Abstract
Cometabolism mechanisms of organic pollutants in environmental microbes have not been fully understood. In this study, a global analysis of Mycobacterium sp. strain A1-PYR transcriptomes on different PAH substrates (single or binary of pyrene (PYR) and phenanthrene (PHE)) was conducted. Comparative results demonstrated that expression levels of 23 PAH degradation enzymes were significantly higher in the binary substrate than in the PYR-only one. These enzymes constituted an integrated enzymatic system to actualize all transformation steps of PYR, and most of their encoded genes formed a novel gene cascade in the genome of strain A1-PYR. The roles of different genotypes of enzymes in PYR cometabolism were also discriminated even though all of their gene sequences were presented in the genome of this strain. NidAB and PdoA2B2 instead of NidA3B3 served the initial oxidization of PAHs, and PcaL replaced PcaCD to catalyze the formation of 3-oxoadipate. Novel genes associated with PYR cometabolism was also predicted by the relationships between their transcription profiles and PYR removal. The results showed that ABC-type transporters probably played important roles in the transport of PAHs and their metabolites through cell membrane, and [4Fe-4S] ferredoxin might be essential for dioxygenases (NidAB and PdoA2B2) to achieve oxidative activities. This study provided molecular insight in that microbial degrader subtly cometabolized recalcitrant PAHs with relatively more degradable ones.
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Affiliation(s)
- Ke Yuan
- Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, School of Marine Sciences, Sun Yat-Sen University, Guangzhou, 510275, People's Republic of China; School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, People's Republic of China
| | - Xiuqin Xie
- School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, People's Republic of China
| | - Xiaowei Wang
- Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, School of Marine Sciences, Sun Yat-Sen University, Guangzhou, 510275, People's Republic of China
| | - Li Lin
- School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, People's Republic of China
| | - Lihua Yang
- Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, School of Marine Sciences, Sun Yat-Sen University, Guangzhou, 510275, People's Republic of China
| | - Tiangang Luan
- Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, School of Marine Sciences, Sun Yat-Sen University, Guangzhou, 510275, People's Republic of China; School of Life Sciences, Sun Yat-Sen University, Guangzhou, 510275, People's Republic of China
| | - Baowei Chen
- Guangdong Provincial Key Laboratory of Marine Resources and Coastal Engineering, School of Marine Sciences, Sun Yat-Sen University, Guangzhou, 510275, People's Republic of China.
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Peng L, Kassotaki E, Liu Y, Sun J, Dai X, Pijuan M, Rodriguez-Roda I, Buttiglieri G, Ni BJ. Modelling cometabolic biotransformation of sulfamethoxazole by an enriched ammonia oxidizing bacteria culture. Chem Eng Sci 2017. [DOI: 10.1016/j.ces.2017.08.015] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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8
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Zalesak M, Ruzicka J, Vicha R, Dvorackova M. Cometabolic degradation of dichloroethenes by Comamonas testosteroni RF2. CHEMOSPHERE 2017; 186:919-927. [PMID: 28830064 DOI: 10.1016/j.chemosphere.2017.07.156] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2017] [Revised: 06/28/2017] [Accepted: 07/29/2017] [Indexed: 06/07/2023]
Abstract
An environmental isolate Comamonas testosteroni strain RF2, which has been found to cometabolize trichloroethene (TCE) in the presence of phenol and sodium lactate as growth substrates, was tested to investigate its capacity for degrading 1,2-cis-dichloroethene (cDCE), 1,2-trans-dichlorothene (tDCE), and 1,1-dichloroethene (1,1DCE). Degradation assays were performed for single DCEs, as well as for a mixture of DCEs with TCE, which resembled contaminated plume in groundwater. RF2 was capable of efficiently removing all three dichloroethenes (DCEs) at the initial aqueous concentrations of 6.01 mg L-1 for cDCE, 3.80 mg L-1 for tDCE and 0.65 mg L-1 for 1,1DCE, with a removal efficiency of 100% for cDCE, 65.8% for tDCE, and 46.8% for 1,1DCE. Furthermore, complete removal of TCE, cDCE and 1,1DCE (122.5 μg L-1, 84.3 μg L-1 and 51.4 μg L-1, respectively) was observed in a mixture sample that also contained 72.33 μg L-1 of tDCE, which was removed to the amount of 72.3%. Moreover, degradation of cDCE (6.01 mg L-1) led to a 93.8% release of inorganic chloride, and 2,2-dichloroacetaldehyde was determined as the first intermediate of cDCE transformation. The findings of this study suggest that the strain RF2 exhibits the potential to remediate groundwater contaminated with less chlorinated ethenes.
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Affiliation(s)
- Michal Zalesak
- Department of Environment Protection Engineering, Tomas Bata University in Zlin, Faculty of Technology, Vavreckova 275, 760 01, Zlin, Czech Republic.
| | - Jan Ruzicka
- Department of Environment Protection Engineering, Tomas Bata University in Zlin, Faculty of Technology, Vavreckova 275, 760 01, Zlin, Czech Republic.
| | - Robert Vicha
- Department of Chemistry, Tomas Bata University in Zlin, Faculty of Technology, Vavreckova 275, 760 01, Zlin, Czech Republic.
| | - Marie Dvorackova
- Department of Environment Protection Engineering, Tomas Bata University in Zlin, Faculty of Technology, Vavreckova 275, 760 01, Zlin, Czech Republic.
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Fraraccio S, Strejcek M, Dolinova I, Macek T, Uhlik O. Secondary compound hypothesis revisited: Selected plant secondary metabolites promote bacterial degradation of cis-1,2-dichloroethylene (cDCE). Sci Rep 2017; 7:8406. [PMID: 28814712 PMCID: PMC5559444 DOI: 10.1038/s41598-017-07760-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Accepted: 06/29/2017] [Indexed: 12/20/2022] Open
Abstract
Cis-1,2-dichloroethylene (cDCE), which is a common hazardous compound, often accumulates during incomplete reductive dechlorination of higher chlorinated ethenes (CEs) at contaminated sites. Simple monoaromatics, such as toluene and phenol, have been proven to induce biotransformation of cDCE in microbial communities incapable of cDCE degradation in the absence of other carbon sources. The goal of this microcosm-based laboratory study was to discover non-toxic natural monoaromatic secondary plant metabolites (SPMEs) that could enhance cDCE degradation in a similar manner to toluene and phenol. Eight SPMEs were selected on the basis of their monoaromatic molecular structure and widespread occurrence in nature. The suitability of the SPMEs chosen to support bacterial growth and to promote cDCE degradation was evaluated in aerobic microbial cultures enriched from cDCE-contaminated soil in the presence of each SPME tested and cDCE. Significant cDCE depletions were achieved in cultures enriched on acetophenone, phenethyl alcohol, p-hydroxybenzoic acid and trans-cinnamic acid. 16S rRNA gene sequence analysis of each microbial community revealed ubiquitous enrichment of bacteria affiliated with the genera Cupriavidus, Rhodococcus, Burkholderia, Acinetobacter and Pseudomonas. Our results provide further confirmation of the previously stated secondary compound hypothesis that plant metabolites released into the rhizosphere can trigger biodegradation of environmental pollutants, including cDCE.
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Affiliation(s)
- Serena Fraraccio
- University of Chemistry and Technology, Prague, Faculty of Food and Biochemical Technology, Department of Biochemistry and Microbiology, Prague, Czech Republic.
| | - Michal Strejcek
- University of Chemistry and Technology, Prague, Faculty of Food and Biochemical Technology, Department of Biochemistry and Microbiology, Prague, Czech Republic
| | - Iva Dolinova
- Technical University of Liberec, Liberec, Czech Republic
| | - Tomas Macek
- University of Chemistry and Technology, Prague, Faculty of Food and Biochemical Technology, Department of Biochemistry and Microbiology, Prague, Czech Republic
| | - Ondrej Uhlik
- University of Chemistry and Technology, Prague, Faculty of Food and Biochemical Technology, Department of Biochemistry and Microbiology, Prague, Czech Republic.
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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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11
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Xu Y, Yuan Z, Ni BJ. Biotransformation of pharmaceuticals by ammonia oxidizing bacteria in wastewater treatment processes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 566-567:796-805. [PMID: 27243932 DOI: 10.1016/j.scitotenv.2016.05.118] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 05/13/2016] [Accepted: 05/17/2016] [Indexed: 06/05/2023]
Abstract
Pharmaceutical residues could potentially pose detrimental effects on aquatic ecosystems and human health, with wastewater treatment being one of the major pathways for pharmaceuticals to enter into the environment. Enhanced removal of pharmaceuticals by ammonia oxidizing bacteria (AOB) has been widely observed in wastewater treatment processes. This article reviews the current knowledge on the biotransformation of pharmaceuticals by AOB. The relationship between the pharmaceuticals removal and nitrification process was revealed. The important role of AOB-induced cometabolism on the biotransformation of pharmaceuticals as well as their transformation products and pathways was elucidated. Kinetics and mathematical models describing the biotransformation of pharmaceuticals by AOB were also reviewed. The results highlighted the high degradation capabilities of AOB toward some refractory pharmaceuticals, with their degradations being clearly related to the nitrification rate and their transformation products being identified, which may exhibit similar or higher ecotoxicological impacts compared to the parent compound.
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Affiliation(s)
- Yifeng Xu
- Advanced Water Management Centre, The University of Queensland, St. Lucia, Brisbane, QLD, 4072, Australia
| | - Zhiguo Yuan
- Advanced Water Management Centre, The University of Queensland, St. Lucia, Brisbane, QLD, 4072, Australia
| | - Bing-Jie Ni
- Advanced Water Management Centre, The University of Queensland, St. Lucia, Brisbane, QLD, 4072, Australia.
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12
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Puigserver D, Herrero J, Torres M, Cortés A, Nijenhuis I, Kuntze K, Parker BL, Carmona JM. Reductive dechlorination in recalcitrant sources of chloroethenes in the transition zone between aquifers and aquitards. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2016; 23:18724-41. [PMID: 27314420 DOI: 10.1007/s11356-016-7068-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 06/09/2016] [Indexed: 05/20/2023]
Abstract
In the transition zone between aquifers and basal aquitards, the perchloroethene pools at an early time in their evolution are more recalcitrant than those elsewhere in the aquifer. The aim of this study is to demonstrate that the biodegradation of chloroethenes from aged pools (i.e., pools after decades of continuous groundwater flushing and dissolution) of perchloroethene is favored in the transition zone. A field site was selected where an aged pool exists at the bottom of a transition zone. Two boreholes were drilled to obtain sediment and groundwater samples to perform chemical, isotopic, molecular, and clone library analyses and microcosm experiments. The main results were as follows: (i) the transition zone is characterized by a high microbial richness; (ii) reductively dechlorinating microorganisms are present and partial reductive dechlorination coexists with denitrification, Fe and Mn reduction, and sulfate reduction; (iii) reductively dechlorinating microorganisms were also present in the zone of the aged pool; (v) the high concentrations of perchloroethene in this zone resulted in a decrease in microbial richness; (vi) however, the presence of fermenting microorganisms supplying electrons for the reductively dechlorinating microorganisms prevented the reductive dechlorination to be inhibited. These findings suggest that biostimulation and/or bioaugmentation could be applied to promote complete reductive dechlorination and to enhance the dissolution of more nonaqueous phase liquids (DNAPL).
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Affiliation(s)
- Diana Puigserver
- Department de Gequímica, Petrologia i Prospecció Geològica, Facultat de Geologia, Universitat de Barcelona, C/ Martí i Franquès, s/n, 08028, Barcelona, Spain
| | - Jofre Herrero
- Department de Gequímica, Petrologia i Prospecció Geològica, Facultat de Geologia, Universitat de Barcelona, C/ Martí i Franquès, s/n, 08028, Barcelona, Spain
| | - Mònica Torres
- Department de Gequímica, Petrologia i Prospecció Geològica, Facultat de Geologia, Universitat de Barcelona, C/ Martí i Franquès, s/n, 08028, Barcelona, Spain
| | - Amparo Cortés
- Departament de Productes Naturals, Biologia Vegetal i Edafologia, Facultat de Farmàcia, Universitat de Barcelona, Av. Joan XXIII, s/n., 08028, Barcelona, Spain
| | - Ivonne Nijenhuis
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research (UFZ), Permoserstrasse 15., 04318, Leipzig, Germany
| | - Kevin Kuntze
- Department of Isotope Biogeochemistry, Helmholtz Centre for Environmental Research (UFZ), Permoserstrasse 15., 04318, Leipzig, Germany
| | - Beth L Parker
- School of Engineering, University of Guelph, 50, Stone Road East, Guelph, ON, N1G 2W1, Canada
| | - José M Carmona
- Department de Gequímica, Petrologia i Prospecció Geològica, Facultat de Geologia, Universitat de Barcelona, C/ Martí i Franquès, s/n, 08028, Barcelona, Spain.
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Jesus J, Frascari D, Pozdniakova T, Danko AS. Kinetics of aerobic cometabolic biodegradation of chlorinated and brominated aliphatic hydrocarbons: A review. JOURNAL OF HAZARDOUS MATERIALS 2016; 309:37-52. [PMID: 26874310 DOI: 10.1016/j.jhazmat.2016.01.065] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2015] [Revised: 01/25/2016] [Accepted: 01/26/2016] [Indexed: 06/05/2023]
Abstract
This review analyses kinetic studies of aerobic cometabolism (AC) of halogenated aliphatic hydrocarbons (HAHs) from 2001-2015 in order to (i) compare the different kinetic models proposed, (ii) analyse the estimated model parameters with a focus on novel HAHs and the identification of general trends, and (iii) identify further research needs. The results of this analysis show that aerobic cometabolism can degrade a wide range of HAHs, including HAHs that were not previously tested such as chlorinated propanes, highly chlorinated ethanes and brominated methanes and ethanes. The degree of chlorine mineralization was very high for the chlorinated HAHs. Bromine mineralization was not determined for studies with brominated aliphatics. The examined research period led to the identification of novel growth substrates of potentially high interest. Decreasing performance of aerobic cometabolism were found with increasing chlorination, indicating the high potential of aerobic cometabolism in the presence of medium- and low-halogenated HAHs. Further research is needed for the AC of brominated aliphatic hydrocarbons, the potential for biofilm aerobic cometabolism processes, HAH-HAH mutual inhibition and the identification of the enzymes responsible for each aerobic cometabolism process. Lastly, some indications for a possible standardization of future kinetic studies of HAH aerobic cometabolism are provided.
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Affiliation(s)
- João Jesus
- Centre for Natural Resources and the Environment (CERENA), Department of Mining Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal.
| | - Dario Frascari
- Department of Civil, Chemical, Environmental and Materials Engineering, University of Bologna, Via Terracini 28, 40131 Bologna, Italy.
| | - Tatiana Pozdniakova
- LSRE-Laboratory of Separation and Reaction Engineering, Associate Laboratory LSRE-LCM, Chemical Engineering Department, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal.
| | - Anthony S Danko
- Centre for Natural Resources and the Environment (CERENA), Department of Mining Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal.
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Li J, Lu Q, de Toledo RA, Lu Y, Shim H. Effect of toluene concentration and hydrogen peroxide on Pseudomonas plecoglossicida cometabolizing mixture of cis-DCE and TCE in soil slurry. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2015; 37:985-995. [PMID: 25963576 DOI: 10.1007/s10653-015-9707-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2014] [Accepted: 04/28/2015] [Indexed: 06/04/2023]
Abstract
An indigenous Pseudomonas sp., isolated from the regional contaminated soil and identified as P. plecoglossicida, was evaluated for its aerobic cometabolic removal of cis-1,2-dichloroethylene (cis-DCE) and trichloroethylene (TCE) using toluene as growth substrate in a laboratory-scale soil slurry. The aerobic simultaneous bioremoval of the cis-DCE/TCE/toluene mixture was studied under different conditions. Results showed that an increase in toluene concentration level from 300 to 900 mg/kg prolonged the lag phase for the bacterial growth, while the bioremoval extent for cis-DCE, TCE, and toluene declined as the initial toluene concentration increased. In addition, the cometabolic bioremoval of cis-DCE and TCE was inhibited by the presence of hydrogen peroxide as the additional oxygen source, while the bioremoval of toluene (900 mg/kg) was enhanced after 9 days of incubation. The subsequent addition of toluene did not improve the cometabolic bioremoval of cis-DCE and TCE. The obtained results would help to enhance the applicability of bioremediation technology to the mixed waste contaminated sites.
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Affiliation(s)
- Junhui Li
- College of Natural Resources and Environmental Science, South China Agricultural University, Guangzhou, 510642, China
- Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau SAR, 999078, China
- Key Laboratory of the Ministry of Land and Resources for Construction Land Transformation, South China Agricultural University, Guangzhou, 510642, China
- Guangdong Provincial Key Laboratory of Land Use and Consolidation, South China Agricultural University, Guangzhou, 510642, China
| | - Qihong Lu
- Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau SAR, 999078, China
| | - Renata Alves de Toledo
- Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau SAR, 999078, China
| | - Ying Lu
- College of Natural Resources and Environmental Science, South China Agricultural University, Guangzhou, 510642, China.
| | - Hojae Shim
- Department of Civil and Environmental Engineering, Faculty of Science and Technology, University of Macau, Macau SAR, 999078, China.
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Liu L, Binning PJ, Smets BF. Evaluating alternate biokinetic models for trace pollutant cometabolism. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:2230-6. [PMID: 25546565 DOI: 10.1021/es5035393] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Mathematical models of cometabolic biodegradation kinetics can improve our understanding of the relevant microbial reactions and allow us to design in situ or in-reactor applications of cometabolic bioremediation. A variety of models are available, but their ability to describe experimental data has not been systematically evaluated for a variety of operational/experimental conditions. Here five different models were considered: first-order; Michaelis-Menten; reductant; competition; and combined models. The models were assessed on their ability to fit data from simulated batch experiments covering a realistic range of experimental conditions. The simulated observations were generated by using the most complex model structure and parameters based on the literature, with added experimental error. Three criteria were used to evaluate model fit: ability to fit the simulated experimental data, identifiability of parameters using a colinearity analysis, and suitability of the model size and complexity using the Bayesian and Akaike Information criteria. Results show that no single model fits data well for a range of experimental conditions. The reductant model achieved best results, but required very different parameter sets to simulate each experiment. Parameter nonuniqueness was likely to be due to the parameter correlation. These results suggest that the cometabolic models must be further developed if they are to reliably simulate experimental and operational data.
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Affiliation(s)
- Li Liu
- Department of Environmental Engineering, Technical, University of Denmark , Bygningstorvet 115, 2800 Kgs.Lyngby, Denmark
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16
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Kurt Z, Mack EE, Spain JC. Biodegradation of cis-dichloroethene and vinyl chloride in the capillary fringe. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:13350-13357. [PMID: 25329424 DOI: 10.1021/es503071m] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Volatile chlorinated compounds are major pollutants in groundwater, and they pose a risk of vapor intrusion into buildings. Vapor intrusion can be prevented by natural attenuation in the vadose zone if biodegradation mechanisms can be established. In this study, we tested the hypothesis that bacteria can use cis-dichloroethene (cis-DCE) or vinyl chloride (VC) as an electron donor in the vadose zone. Anoxic water containing cis-DCE or VC was pumped continuously beneath laboratory columns that represented the vadose zone. Columns were inoculated with Polaromonas sp. strain JS666, which grows aerobically on cis-DCE, or with Mycobacterium sp. JS60 and Nocardiodes sp. JS614 that grow on VC. Complete biodegradation with fluxes of 84 ± 15 μmol of cis-DCE · m(-2) · hr(-1) and 218 ± 25 μmole VC·m(-2) · h(-1) within the 23 cm column indicated that microbial activities can prevent the migration of cis-DCE and VC vapors. Oxygen and volatile compound profiles along with enumeration of bacterial populations indicated that most of the biodegradation took place in the first 10 cm above the saturated zone within the capillary fringe. The results revealed that cis-DCE and VC can be biodegraded readily at the oxic/anoxic interfaces in the vadose zone if appropriate microbes are present.
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Affiliation(s)
- Zohre Kurt
- School of Civil and Environmental Engineering, Georgia Institute of Technology , Atlanta, Georgia 30332-0512, United States
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17
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Frascari D, Zanaroli G, Danko AS. In situ aerobic cometabolism of chlorinated solvents: a review. JOURNAL OF HAZARDOUS MATERIALS 2014; 283:382-399. [PMID: 25306537 DOI: 10.1016/j.jhazmat.2014.09.041] [Citation(s) in RCA: 55] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Revised: 09/04/2014] [Accepted: 09/05/2014] [Indexed: 06/04/2023]
Abstract
The possible approaches for in situ aerobic cometabolism of aquifers and vadose zones contaminated by chlorinated solvents are critically evaluated. Bioaugmentation of resting-cells previously grown in a fermenter and in-well addition of oxygen and growth substrate appear to be the most promising approaches for aquifer bioremediation. Other solutions involving the sparging of air lead to satisfactory pollutant removals, but must be integrated by the extraction and subsequent treatment of vapors to avoid the dispersion of volatile chlorinated solvents in the atmosphere. Cometabolic bioventing is the only possible approach for the aerobic cometabolic bioremediation of the vadose zone. The examined studies indicate that in situ aerobic cometabolism leads to the biodegradation of a wide range of chlorinated solvents within remediation times that vary between 1 and 17 months. Numerous studies include a simulation of the experimental field data. The modeling of the process attained a high reliability, and represents a crucial tool for the elaboration of field data obtained in pilot tests and for the design of the full-scale systems. Further research is needed to attain higher concentrations of chlorinated solvent degrading microbes and more reliable cost estimates. Lastly, a procedure for the design of full-scale in situ aerobic cometabolic bioremediation processes is proposed.
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Affiliation(s)
- Dario Frascari
- Department of Civil, Chemical, Environmental and Materials Engineering, University of Bologna, Via Terracini 28, 40131 Bologna, Italy.
| | - Giulio Zanaroli
- Department of Civil, Chemical, Environmental and Materials Engineering, University of Bologna, Via Terracini 28, 40131 Bologna, Italy.
| | - Anthony S Danko
- Geo-Environmental and Resources Research Center, Department of Mining Engineering, University of Porto, Rua Dr. Roberto Frias, s/n, 4200-465 Porto, Portugal; Centre for Natural Resources and the Environment (CERENA), Instituto Superior Técnico, Av. Rovisco Pais, 1049-001 Lisboa, Portugal.
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18
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Frascari D, Zanaroli G, Bucchi G, Rosato A, Tavanaie N, Fraraccio S, Pinelli D, Fava F. Trichloroethylene aerobic cometabolism by suspended and immobilized butane-growing microbial consortia: a kinetic study. BIORESOURCE TECHNOLOGY 2013; 144:529-538. [PMID: 23896437 DOI: 10.1016/j.biortech.2013.07.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2013] [Revised: 06/28/2013] [Accepted: 07/02/2013] [Indexed: 06/02/2023]
Abstract
A kinetic study of butane uptake and trichloroethylene (TCE) aerobic cometabolism was conducted by two suspended-cell (15 and 30°C) and two attached-cell (15 and 30°C) consortia obtained from the indigenous biomass of a TCE-contaminated aquifer. The shift from suspended to attached cells resulted in an increase of butane (15 and 30°C) and TCE (15°C) biodegradation rates, and a significant decrease of butane inhibition on TCE biodegradation. The TCE 15°C maximum specific biodegradation rate was equal to 0.011 mg(TCE ) mg(protein)(-1) d(-1) with suspended cells and 0.021 mg(TCE) mg(protein)(-1) d(-1) with attached cells. The type of mutual butane/TCE inhibition depended on temperature and biomass conditions. On the basis of a continuous-flow simulation, a packed-bed PFR inoculated with the 15 or 30°C attached-cell consortium could attain a 99.96% conversion of the studied site's average TCE concentration with a 0.4-0.5-day hydraulic residence time, with a low effect of temperature on the TCE degradation performances.
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Affiliation(s)
- Dario Frascari
- Department of Civil, Chemical, Environmental and Materials Engineering, University of Bologna, Bologna, Italy.
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19
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Shani N, Rossi P, Holliger C. Correlations between environmental variables and bacterial community structures suggest Fe(III) and vinyl chloride reduction as antagonistic terminal electron-accepting processes. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2013; 47:6836-6845. [PMID: 23484639 DOI: 10.1021/es304017s] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Natural attenuation of anaerobic aquifers contaminated with tetrachloroethene (PCE) often results in the accumulation of the intermediates cis-dichloroethene and vinyl chloride (VC) which are even more toxic than the parent compound. Reasons for this accumulation were investigated in a PCE-contaminated aquifer in which VC accumulation has previously been shown to occur using stable isotope techniques. Multifactorial analysis of bacterial community structure data and environmental variables showed that in general terminal electron-accepting processes were shaping the bacterial community structures. Both VC and Fe(III) reduction were key but antagonistic terminal electron-accepting processes. The phylogenetic affiliation of terminal restriction fragments (T-RFs), together with correlation analyses, showed that T-RFs having significant correlation with VC reduction were closely affiliated to the genus Dehalococcoides and to uncultured bacteria belonging to the "Lahn Cluster" within the class Dehalococcoidetes. A T-RF that negatively correlated with a "Lahn Cluster" T-RF was affiliated to the genus Rhodoferax that contains members identified as iron-reducing bacteria. The higher affinity of Fe(III)-reducing bacteria for hydrogen compared with VC-reducing bacteria might explain why VC accumulated locally at the studied site. In conclusion, the combination of molecular and numerical ecology approaches was helpful to identify reasons for the accumulation of toxic dechlorination intermediates and could become a useful tool for characterizing contaminated sites in general.
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Affiliation(s)
- Noam Shani
- Laboratory for Environmental Biotechnology, School of Architecture, Civil and Environmental Engineering, Ecole Polytechnique Fédérale de Lausanne, EPFL ENAC IIE LBE, Station 6, 1015, Lausanne, Switzerland
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Cytochrome P450 initiates degradation of cis-dichloroethene by Polaromonas sp. strain JS666. Appl Environ Microbiol 2013; 79:2263-72. [PMID: 23354711 DOI: 10.1128/aem.03445-12] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Polaromonas sp. strain JS666 grows on cis-1,2-dichoroethene (cDCE) as the sole carbon and energy source under aerobic conditions, but the degradation mechanism and the enzymes involved are unknown. In this study, we established the complete pathway for cDCE degradation through heterologous gene expression, inhibition studies, enzyme assays, and analysis of intermediates. Several lines of evidence indicate that a cytochrome P450 monooxygenase catalyzes the initial step of cDCE degradation. Both the transient accumulation of dichloroacetaldehyde in cDCE-degrading cultures and dichloroacetaldehyde dehydrogenase activities in cell extracts of JS666 support a pathway for degradation of cDCE through dichloroacetaldehyde. The mechanism minimizes the formation of cDCE epoxide. The molecular phylogeny of the cytochrome P450 gene and the organization of neighboring genes suggest that the cDCE degradation pathway recently evolved in a progenitor capable of degrading 1,2-dichloroethane either by the recruitment of the cytochrome P450 monooxygenase gene from an alkane catabolic pathway or by selection for variants of the P450 in a preexisting 1,2-dichloroethane catabolic pathway. The results presented here add yet another role to the broad array of productive reactions catalyzed by cytochrome P450 enzymes.
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21
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Efficacy of pentane, toluene, and benzene to support aerobic cometabolism of ethylene dibromide. N Biotechnol 2012; 30:39-43. [PMID: 22613211 DOI: 10.1016/j.nbt.2012.05.001] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2012] [Revised: 05/03/2012] [Accepted: 05/09/2012] [Indexed: 11/21/2022]
Abstract
The ability of pentane, benzene, and toluene to support aerobic cometabolism of ethylene dibromide (1,2-dibromoethane, EDB) was evaluated. A pentane enrichment culture cometabolized EDB, with a transformation capacity of 0.35 μmol EDB/mg biomass (66.2 μg EDB/mg biomass) in the absence of growth substrate. It also cometabolized EDB while actively growing on pentane. However, enrichment cultures grown on benzene or toluene could not cometabolize EDB, with or without their respective growth substrates.
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Lohner ST, Becker D, Mangold KM, Tiehm A. Sequential reductive and oxidative biodegradation of chloroethenes stimulated in a coupled bioelectro-process. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2011; 45:6491-6497. [PMID: 21678913 DOI: 10.1021/es200801r] [Citation(s) in RCA: 60] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
This article for the first time demonstrates successful application of electrochemical processes to stimulate sequential reductive/oxidative microbial degradation of perchloroethene (PCE) in mineral medium and in contaminated groundwater. In a flow-through column system, hydrogen generation at the cathode supported reductive dechlorination of PCE to cis-dichloroethene (cDCE), vinyl chloride (VC), and ethene (ETH). Electrolytically generated oxygen at the anode allowed subsequent oxidative degradation of the lower chlorinated metabolites. Aerobic cometabolic degradation of cDCE proved to be the bottleneck for complete metabolite elimination. Total removal of chloroethenes was demonstrated for a PCE load of approximately 1.5 μmol/d. In mineral medium, long-term operation with stainless steel electrodes was demonstrated for more than 300 days. In contaminated groundwater, corrosion of the stainless steel anode occurred, whereas DSA (dimensionally stable anodes) proved to be stable. Precipitation of calcareous deposits was observed at the cathode, resulting in a higher voltage demand and reduced dechlorination activity. With DSA and groundwater from a contaminated site, complete degradation of chloroethenes in groundwater was obtained for two months thus demonstrating the feasibility of the sequential bioelectro-approach for field application.
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Affiliation(s)
- Svenja T Lohner
- Water Technology Center, Department of Environmental Biotechnology, Karlsruhe, Germany
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Biodegradation of vinyl chloride, cis-dichloroethene and 1,2-dichloroethane in the alkene/alkane-oxidising Mycobacterium strain NBB4. Biodegradation 2011; 22:1095-108. [DOI: 10.1007/s10532-011-9466-0] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2010] [Accepted: 02/21/2011] [Indexed: 10/18/2022]
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24
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Mattes TE, Alexander AK, Coleman NV. Aerobic biodegradation of the chloroethenes: pathways, enzymes, ecology, and evolution. FEMS Microbiol Rev 2010; 34:445-75. [DOI: 10.1111/j.1574-6976.2010.00210.x] [Citation(s) in RCA: 113] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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Zhao HP, Schmidt KR, Tiehm A. Inhibition of aerobic metabolic cis-1,2-di-chloroethene biodegradation by other chloroethenes. WATER RESEARCH 2010; 44:2276-2282. [PMID: 20079512 DOI: 10.1016/j.watres.2009.12.023] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2009] [Revised: 11/09/2009] [Accepted: 12/11/2009] [Indexed: 05/28/2023]
Abstract
The presence of other chloroethenes influences aerobic metabolic biodegradation of cis-1,2-dichloroethene (cDCE). A new metabolically cDCE degrading enrichment culture was identified as also being capable of degrading vinyl chloride (VC), but not 1,1-dichloroethene (1,1DCE), trans-1,2-dichloroethene (tDCE), trichloroethene (TCE), or tetrachloroethene (PCE). The fastest degradation of cDCE was observed in the absence of any other chloroethene. In the presence of a second chloroethene (40-90 microM), the rate of cDCE (60 microM) degradation decreased in the following order: cDCE (+PCE) > cDCE (+tDCE) > cDCE (+VC)>cDCE (+1,1DCE) approximately cDCE (+TCE). With increasing concentrations of VC, ranging from 10 to 110 microM, the rate of cDCE (60 microM) degradation decreased. This study demonstrates that the inhibiting effects of chloroethene mixtures have to be considered during laboratory studies and bioremediation approaches based on metabolic cDCE degradation.
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Affiliation(s)
- He-Ping Zhao
- Department of Environmental Biotechnology, Water Technology Center, 76139 Karlsruhe, Germany.
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Schmidt KR, Augenstein T, Heidinger M, Ertl S, Tiehm A. Aerobic biodegradation of cis-1,2-dichloroethene as sole carbon source: Stable carbon isotope fractionation and growth characteristics. CHEMOSPHERE 2010; 78:527-532. [PMID: 20042217 DOI: 10.1016/j.chemosphere.2009.11.033] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2009] [Revised: 11/20/2009] [Accepted: 11/23/2009] [Indexed: 05/28/2023]
Abstract
Cis-1,2-dichloroethene (cDCE) is a compound of concern at many chloroethene-contaminated sites, since it tends to accumulate during reductive dechlorination of the higher chlorinated ethenes. Stable carbon isotope fractionation during aerobic cDCE biodegradation was observed in groundwater microcosms under varying incubation conditions (room temperature/groundwater temperature; with/without inorganic nutrients), and resulted in an average stable carbon isotope enrichment factor of -15.2+/-0.5 per thousand. A new enrichment culture, obtained from groundwater microcosms, degraded cDCE concentrations up to 100mgL(-1), was active at temperatures between 4 and 23 degrees C, had a pH optimum of approximately 7, and could withstand prolonged periods (250d) of starvation. Microbial growth during degradation of cDCE as sole carbon and energy source was demonstrated by protein formation in mineral medium not containing any known auxiliary substrate. The obtained growth yield was 12.5+/-1.9g of proteinMol(-1) of cDCE, with a doubling time of 53+/-2h at 23 degrees C. Aerobic degradation of cDCE as sole carbon and energy source appears to be a promising biological process for site remediation.
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Affiliation(s)
- Kathrin R Schmidt
- Department of Environmental Biotechnology, Water Technology Center, Karlsruhe, Germany
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Frascari D, Pinelli D, Nocentini M, Baleani E, Cappelletti M, Fedi S. A kinetic study of chlorinated solvent cometabolic biodegradation by propane-grown Rhodococcus sp. PB1. Biochem Eng J 2008. [DOI: 10.1016/j.bej.2008.06.011] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Tawney I, Becker JG, Baldwin AH. A novel dual-compartment, continuous-flow wetland microcosm to assess cis-dichloroethene removal from the rhizosphere. INTERNATIONAL JOURNAL OF PHYTOREMEDIATION 2008; 10:455-471. [PMID: 19260226 DOI: 10.1080/15226510802100655] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The anaerobic biodegradation of tetrachloroethene commonly results in the accumulation of chlorinated intermediates such as cis-1,2-dichloroethene (cDCE). Frequently, groundwater contaminated with chlorinated ethenes discharges to natural wetlands. The goal of this study was to quantitatively evaluate the effects of wetland plants and microorganisms on the fate of cDCE in the wetland rhizosphere. To accomplish this goal, a novel dual-compartment wetland microcosm was designed. A Phragmites australis individual was maintained in the microcosm, which was operated with continuous flows of air and mineral medium through the foliar and rhizosphere compartments, respectively, to incorporate mass transfer/transport processes that are important in natural wetlands and allow steady-state assessment of changes in dissolved O2 and cDCE or [1,2-(14)C]cDCE levels. Substantial amounts of [14C]cDCE were phytovolatilized through a healthy P. australis individual to the foliar chamber. Rhizodegradation by native microorganisms associated with P. australis roots also converted substantial amounts of [14C]cDCE to 14C-labeled CO2 and non-volatile compounds, presumably through cometabolic reactions that could be enhanced by the release of O2 and exudates by P. australis. These results suggest that, in some cases, the intrinsic capacity of native wetland plants and microorganisms to remove cDCE from the rhizosphere may be substantial.
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Affiliation(s)
- Ilisa Tawney
- Department of Environmental Science and Technology, University of Maryland, College Park, Maryland 20742-2315, USA
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Tiehm A, Schmidt KR, Pfeifer B, Heidinger M, Ertl S. Growth kinetics and stable carbon isotope fractionation during aerobic degradation of cis-1,2-dichloroethene and vinyl chloride. WATER RESEARCH 2008; 42:2431-2438. [PMID: 18313719 DOI: 10.1016/j.watres.2008.01.029] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2007] [Revised: 01/16/2008] [Accepted: 01/23/2008] [Indexed: 05/26/2023]
Abstract
Assessing changes in the isotopic signature of contaminants is a promising new tool to monitor microbial degradation processes. In this study, chloroethene degradation was proven by depletion of chloroethenes, formation of chloride, increase in protein content and stable carbon isotope fractionation. Aerobic degradation of vinyl chloride (VC) was found to proceed metabolically, with degradation rates of 0.48 and 0.29 d(-1); and growth yields of 9.7 and 6.4 g of protein/mol of VC at room and groundwater temperature, respectively. Cis-1,2-dichloroethene (cDCE) was degraded cometabolically under aerobic conditions when VC was provided as growth substrate. Aerobic degradation was associated with significant stable carbon isotope fractionation, with enrichment factors ranging from -5.4+/-0.4 per thousand for metabolic degradation of VC to -9.8+/-1.7 per thousand for cometabolic degradation of cDCE. Thus, it was demonstrated that stable carbon isotope fractionation is suitable for assessing aerobic chloroethene degradation, which can contribute significantly to site remediation.
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Affiliation(s)
- Andreas Tiehm
- Department of Environmental Biotechnology, Water Technology Center, Karlsruher Street 84, 76139 Karlsruhe, Germany.
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31
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Sorek A, Atzmon N, Dahan O, Gerstl Z, Kushisin L, Laor Y, Mingelgrin U, Nasser A, Ronen D, Tsechansky L, Weisbrod N, Graber ER. "Phytoscreening": the use of trees for discovering subsurface contamination by VOCs. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2008; 42:536-542. [PMID: 18284159 DOI: 10.1021/es072014b] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
We tested the possibility of using tree cores to detect unknown subsurface contamination by chlorinated volatile organic compounds (Cl-VOCs) and petroleum hydrocarbons, a method we term "phytoscreening". The scope and limitations of the method include the following: (i) a number of widespread Cl-VOC contaminants are readily found in tree cores, although those with very high vapor pressures or low boiling points may be absent; (ii) volatile petroleum hydrocarbons were notwell-expressed in tree cores; (iii) trees should be sampled during active evapotranspiration and from directions that are well exposed to sunlight; (iv) there is not necessarily a direct correlation between concentrations measured in tree cores and those in the subsurface; (v) detection of a contaminant in a tree core indicates that the subsurface is contaminated with the pollutant; (vi) many possible causes of false negatives may be predicted and avoided. We sampled trees at 13 random locations in the Tel Aviv metropolitan area and identified Cl-VOCs in tree coresfromthree locations. Subsequently, subsurface contamination at all three sites was confirmed. Phytoscreening is a simple, fast, noninvasive, and inexpensive screening method for detecting subsurface contamination, and is particularly useful in urban settings where conventional methods are difficult and expensive to employ.
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Affiliation(s)
- A Sorek
- Institute of Soil, Water and Environmental Sciences, The Volcani Center, Agricultural Research Organization, POB 6, Bet Dagan 50250 Israel
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Gualandi G, Frascari D, Pinelli D, Nocentini M. Growth of Chlorinated Solvent-Degrading Consortia in Fed-Batch Bioreactors and Development of a Double-Substrate High-Performing Microbial Inoculum. Eng Life Sci 2007. [DOI: 10.1002/elsc.200620189] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
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Elango VK, Liggenstoffer AS, Fathepure BZ. Biodegradation of vinyl chloride and cis-dichloroethene by a Ralstonia sp. strain TRW-1. Appl Microbiol Biotechnol 2006; 72:1270-5. [PMID: 16642331 DOI: 10.1007/s00253-006-0424-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2006] [Revised: 03/12/2006] [Accepted: 03/13/2006] [Indexed: 10/24/2022]
Abstract
An aerobic bacterium, Ralstonia sp. strain TRW-1, that assimilates vinyl chloride (VC) or ethene (ETH) as the sole carbon source was isolated from a chloroethene-degrading enrichment culture. Phylogenetic analysis of 16S rDNA sequence of the isolate revealed almost 99% sequence similarity to Ralstonia pickettii. To our knowledge, this is the first report describing the isolation of a member of Ralstonia that can degrade VC as the growth substrate. The measured growth yield values for VC and ETH were 11.27 and 18.90 g protein/mole, respectively. The estimated half-velocity constant K (m) values for VC and ETH were 9.09+/-2.97 and 5.73+/-2.96 muM, respectively. These values are almost three- to tenfold higher than for other VC-assimilating Mycobacterium sp. The strain also degrades cis-dichloroethene (cis-DCE) in mineral salts medium containing yeast-extract, beef-extract, casamino acids, or peptone. This ability of the strain TRW-1 to degrade cis-DCE in the presence of a nontoxic, water-soluble substrate is relevant to in-situ remediation of cis-DCE-contaminated aquifers.
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MESH Headings
- Biodegradation, Environmental
- Biotransformation
- DNA, Bacterial/chemistry
- DNA, Bacterial/genetics
- DNA, Ribosomal/chemistry
- DNA, Ribosomal/genetics
- Environmental Microbiology
- Ethyl Chloride/metabolism
- Ethylenes/metabolism
- Genes, rRNA/genetics
- Kinetics
- Molecular Sequence Data
- RNA, Bacterial/genetics
- RNA, Ribosomal, 16S/genetics
- Ralstonia/classification
- Ralstonia/isolation & purification
- Ralstonia/metabolism
- Sequence Analysis, DNA
- Sequence Homology, Nucleic Acid
- Vinyl Chloride/metabolism
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Affiliation(s)
- Vijai K Elango
- Department of Microbiology and Molecular Genetics, Oklahoma State University, 307 Life Sciences East, Stillwater, OK 74078-3020, USA
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Coleman NV, Spain JC. Distribution of the coenzyme M pathway of epoxide metabolism among ethene- and vinyl chloride-degrading Mycobacterium strains. Appl Environ Microbiol 2004; 69:6041-6. [PMID: 14532060 PMCID: PMC201217 DOI: 10.1128/aem.69.10.6041-6046.2003] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
An epoxyalkane:coenzyme M (CoM) transferase (EaCoMT) enzyme was recently found to be active in the aerobic vinyl chloride (VC) and ethene assimilation pathways of Mycobacterium strain JS60. In the present study, EaCoMT activity and genes were investigated in 10 different mycobacteria isolated on VC or ethene from diverse environmental samples. In all cases, epoxyethane metabolism in cell extracts was dependent on CoM, with average specific activities of EaCoMT between 380 and 2,910 nmol/min/mg of protein. PCR with primers based on conserved regions of EaCoMT genes from Mycobacterium strain JS60 and the propene oxidizers Xanthobacter strain Py2 and Rhodococcus strain B-276 yielded fragments (834 bp) of EaCoMT genes from all of the VC- and ethene-assimilating isolates. The Mycobacterium EaCoMT genes form a distinct cluster and are more closely related to the EaCoMT of Rhodococcus strain B-276 than that of Xanthobacter strain Py2. The incongruence of the EaCoMT and 16S rRNA gene trees and the fact that isolates from geographically distant locations possessed almost identical EaCoMT genes suggest that lateral transfer of EaCoMT among the Mycobacterium strains has occurred. Pulsed-field gel electrophoresis revealed large linear plasmids (110 to 330 kb) in all of the VC-degrading strains. In Southern blotting experiments, the strain JS60 EaCoMT gene hybridized to many of the plasmids. The CoM-mediated pathway of epoxide metabolism appears to be universal in alkene-assimilating mycobacteria, possibly because of plasmid-mediated lateral gene transfer.
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Affiliation(s)
- Nicholas V Coleman
- Air Force Research Laboratory-MLQL, Tyndall Air Force Base, Florida 32403, USA
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Coleman NV, Spain JC. Epoxyalkane: coenzyme M transferase in the ethene and vinyl chloride biodegradation pathways of mycobacterium strain JS60. J Bacteriol 2003; 185:5536-45. [PMID: 12949106 PMCID: PMC193758 DOI: 10.1128/jb.185.18.5536-5545.2003] [Citation(s) in RCA: 83] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Mycobacterium strains that grow on ethene and vinyl chloride (VC) are widely distributed in the environment and are potentially useful for biocatalysis and bioremediation. The catabolic pathway of alkene assimilation in mycobacteria is not well characterized. It is clear that the initial step is a monooxygenase-mediated epoxidation that produces epoxyethane from ethene and chlorooxirane from VC, but the enzymes involved in subsequent transformation of the epoxides have not been identified. We investigated epoxyethane metabolism in Mycobacterium strain JS60 and discovered a coenzyme M (CoM)-dependent enzyme activity in extracts from VC- and ethene-grown cells. PCR amplifications using primers targeted at epoxyalkane:CoM transferase (EaCoMT) genes yielded part of the JS60 EaCoMT gene, which was used to clone an 8.4-kb genomic DNA fragment. The complete EaCoMT gene (etnE) was recovered, along with genes (etnABCD) encoding a four-component monooxygenase and two genes possibly involved in acyl-CoA ester metabolism. Reverse transcription-PCR indicated that the etnE and etnA genes were cotranscribed and inducible by ethene and VC. Heterologous expression of the etnE gene in Mycobacterium smegmatis mc(2)155 using the pMV261 vector gave a recombinant strain capable of transforming epoxyethane, epoxypropane, and chlorooxirane. A metabolite identified by mass spectrometry as 2-hydroxyethyl-CoM was produced from epoxyethane. The results indicate that the EaCoMT and monooxygenase enzymes encoded by a single operon (etnEABCD) catalyze the initial reactions in both the VC and ethene assimilation pathways. CoM-mediated reactions appear to be more widespread in bacteria than was previously believed.
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