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Ferdowsi M, Khabiri B, Buelna G, Jones JP, Heitz M. Prolonged operation of a methane biofilter from acclimation to the failure stage. ENVIRONMENTAL TECHNOLOGY 2024; 45:2589-2598. [PMID: 36789628 DOI: 10.1080/09593330.2023.2179421] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2022] [Accepted: 02/05/2023] [Indexed: 06/18/2023]
Abstract
Global warming needs immediate attention to reduce major greenhouse gas emissions such as methane (CH4). Bio-oxidation of dilute CH4 emissions in packed-bed bioreactors such as biofilters has been carried out over recent years at laboratory and large scales. However, a big challenge is to keep CH4 biofilters running for a long period. In this study, a packed-bed lab-scale bioreactor with a specialized inorganic-based filter bed was successfully operated over four years for CH4 elimination. The inoculation of the bioreactor was the active leachate of another CH4 biofilter which resulted in a fast acclimation and removal efficiency (RE) reached 80% after seven weeks of operation for CH4 inlet concentrations ranging from 700 to 800 ppmv and an empty bed residence time (EBRT) of 6 min. During four years of operation, the bioreactor often recorded REs higher than 65% for inlet concentrations in the range of 1900-2200 ppmv and an EBRT of 6 min. The rate and interval of the nutrient supply played an important role in maintaining the bioreactor's high performance over the long operation. Forced shutdowns were unavoidable during the 4-year operation and the bioreactor fully tolerated them with a partial recovery within one week and a progressive recovery over time. In the end, the bioreactor's filter bed started to deteriorate due to a long shutdown of twelve weeks and the extended operation of four years when the RE dropped to below 8% with no sign of returning to its earlier performance.
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Affiliation(s)
- Milad Ferdowsi
- Department of Chemical Engineering and Biotechnological Engineering, Faculty of Engineering, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Bahman Khabiri
- Department of Chemical Engineering and Biotechnological Engineering, Faculty of Engineering, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Gerardo Buelna
- Department of Chemical Engineering and Biotechnological Engineering, Faculty of Engineering, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - J Peter Jones
- Department of Chemical Engineering and Biotechnological Engineering, Faculty of Engineering, Université de Sherbrooke, Sherbrooke, Québec, Canada
| | - Michèle Heitz
- Department of Chemical Engineering and Biotechnological Engineering, Faculty of Engineering, Université de Sherbrooke, Sherbrooke, Québec, Canada
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2
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Beals DG, Puri AW. Linking methanotroph phenotypes to genotypes using a simple spatially resolved model ecosystem. THE ISME JOURNAL 2024; 18:wrae060. [PMID: 38622932 PMCID: PMC11072679 DOI: 10.1093/ismejo/wrae060] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Revised: 02/20/2024] [Accepted: 04/10/2024] [Indexed: 04/17/2024]
Abstract
Connecting genes to phenotypic traits in bacteria is often challenging because of a lack of environmental context in laboratory settings. Laboratory-based model ecosystems offer a means to better account for environmental conditions compared with standard planktonic cultures and can help link genotypes and phenotypes. Here, we present a simple, cost-effective, laboratory-based model ecosystem to study aerobic methane-oxidizing bacteria (methanotrophs) within the methane-oxygen counter gradient typically found in the natural environment of these organisms. Culturing the methanotroph Methylomonas sp. strain LW13 in this system resulted in the formation of a distinct horizontal band at the intersection of the counter gradient, which we discovered was not due to increased numbers of bacteria at this location but instead to an increased amount of polysaccharides. We also discovered that different methanotrophic taxa form polysaccharide bands with distinct locations and morphologies when grown in the methane-oxygen counter gradient. By comparing transcriptomic data from LW13 growing within and surrounding this band, we identified genes upregulated within the band and validated their involvement in growth and band formation within the model ecosystem using knockout strains. Notably, deletion of these genes did not negatively affect growth using standard planktonic culturing methods. This work highlights the use of a laboratory-based model ecosystem that more closely mimics the natural environment to uncover bacterial phenotypes missing from standard laboratory conditions, and to link these phenotypes with their genetic determinants.
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Affiliation(s)
- Delaney G Beals
- Department of Chemistry and the Henry Eyring Center for Cell and Genome Science, University of Utah, Salt Lake City, UT 84112, United States
| | - Aaron W Puri
- Department of Chemistry and the Henry Eyring Center for Cell and Genome Science, University of Utah, Salt Lake City, UT 84112, United States
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3
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Wang J, Wang C, Chu YX, Tian G, He R. Characterization of methanotrophic community and activity in landfill cover soils under dimethyl sulfide stress. WASTE MANAGEMENT (NEW YORK, N.Y.) 2023; 161:263-274. [PMID: 36917925 DOI: 10.1016/j.wasman.2023.02.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 01/13/2023] [Accepted: 02/15/2023] [Indexed: 06/18/2023]
Abstract
Landfill cover soil is the environmental interface between landfills and the atmosphere and plays an important role in mitigating CH4 emission from landfills. Here, stable isotope probing microcosms with CH4 or CH4 and dimethyl sulfide (DMS) were carried out to characterize activity and community structure of methanotrophs in landfill cover soils under DMS stress. The CH4 oxidation activity in the landfill cover soils was not obviously influenced at the DMS concentration of 0.05%, while it was inhibited at the DMS concentrations of 0.1% and 0.2%. DMS-S was mainly oxidized to sulfate (SO42-) in the landfill cover soils. In the landfill cover soils, DMS could inhibit the expression of bacteria and decrease the abundances of pmoA and mmoX genes, while it could prompt the expression of pmoA and mmoX genes. γ-Proteobacteria methanotrophs including Methylocaldum, Methylobacter, Crenothrix and unclassified Methylococcaceae and α-Proteobacteria methanotrophs Methylocystis dominated in assimilating CH4 in the landfill cover soils. Of them, Methylobacter and Crenothrix had strong tolerance to DMS or DMS could promote the growth and activity of Methylobacter and Crenothrix, while Methylocaldum had weak tolerance to DMS and showed an inhibitory effect. Metagenomic analyses showed that methanotrophs had the genes of methanethiol oxidation and could metabolize CH4 and methanethiol simultaneously in the landfill cover soils. These findings suggested that methanotrophs might metabolize sulfur compounds in the landfill cover soils, which may provide the potential application in engineering for co-removal of CH4 and sulfur compounds.
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Affiliation(s)
- Jing Wang
- Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310012, China; Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China
| | - Chen Wang
- Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China
| | - Yi-Xuan Chu
- Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China; School of Civil Engineering and Architecture, Zhejiang University of Science and Technology, Hangzhou 310023, China
| | - Guangming Tian
- Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China
| | - Ruo He
- Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310012, China; Department of Environmental Engineering, Zhejiang University, Hangzhou 310058, China.
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4
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Mrudulakumari Vasudevan U, Mai DHA, Krishna S, Lee EY. Methanotrophs as a reservoir for bioactive secondary metabolites: Pitfalls, insights and promises. Biotechnol Adv 2023; 63:108097. [PMID: 36634856 DOI: 10.1016/j.biotechadv.2023.108097] [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: 10/03/2022] [Revised: 12/10/2022] [Accepted: 01/06/2023] [Indexed: 01/11/2023]
Abstract
Methanotrophs are potent natural producers of several bioactive secondary metabolites (SMs) including isoprenoids, polymers, peptides, and vitamins. Cryptic biosynthetic gene clusters identified from these microbes via genome mining hinted at the vast and hidden SM biosynthetic potential of these microbes. Central carbon metabolism in methanotrophs offers rare pathway intermediate pools that could be further diversified using advanced synthetic biology tools to produce valuable SMs; for example, plant polyketides, rare carotenoids, and fatty acid-derived SMs. Recent advances in pathway reconstruction and production of isoprenoids, squalene, ectoine, polyhydroxyalkanoate copolymer, cadaverine, indigo, and shinorine serve as proof-of-concept. This review provides theoretical guidance for developing methanotrophs as microbial chassis for high-value SMs. We summarize the distinct secondary metabolic potentials of type I and type II methanotrophs, with specific attention to products relevant to biomedical applications. This review also includes native and non-native SMs from methanotrophs, their therapeutic potential, strategies to induce silent biosynthetic gene clusters, and challenges.
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Affiliation(s)
- Ushasree Mrudulakumari Vasudevan
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, Yongin-si, Gyeonggi-do 17104, Republic of Korea
| | - Dung Hoang Anh Mai
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, Yongin-si, Gyeonggi-do 17104, Republic of Korea
| | - Shyam Krishna
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, Yongin-si, Gyeonggi-do 17104, Republic of Korea
| | - Eun Yeol Lee
- Department of Chemical Engineering (BK21 FOUR Integrated Engineering Program), Kyung Hee University, Yongin-si, Gyeonggi-do 17104, Republic of Korea.
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Luo D, Qian J, Fu JX, Liu C, Zhang RX, Huang DN, Zhang L. Responses of anammox to long-term p-nitrophenol stress: From apparent and microscopic phenomena to mechanism simulation. BIORESOURCE TECHNOLOGY 2022; 355:127265. [PMID: 35526714 DOI: 10.1016/j.biortech.2022.127265] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 05/01/2022] [Accepted: 05/02/2022] [Indexed: 06/14/2023]
Abstract
p-Nitrophenol is usually present in ammonia-rich wastewaters produced by some chemical plants. In this work, the response of anammox process to long-term p-nitrophenol stress was investigated. The changes in the efficiency, sludge characteristics, and microorganisms of the anammox system under different levels of p-nitrophenol stress were examined, and the potential stress mechanisms of p-nitrophenol on anammox were further speculated. The results showed that 10-50 mg/L p-nitrophenol had no obvious impact on nitrogen removal efficiency, but stimulated the secretion of more extracellular polymeric substances. 60 mg/L p-nitrophenol caused the nitrogen removal efficiency to decrease by 64.5% in 5 days. Long-term exposure to p-nitrophenol led to 8.6% reduction in Candidatus_Kuenenia abundance and 18.4%-35.9% decrease in the expression level of anammox bacterial functional genes. Molecular simulation indicated that p-nitrophenol could bind to key enzymes of anammox. This study provides new insights into the treatment of wastewater containing p-nitrophenol or phenol by anammox.
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Affiliation(s)
- Di Luo
- School of Municipal and Environmental Engineering, Shenyang Jianzhu University, Shenyang 110168, China
| | - Jie Qian
- School of Resources and Civil Engineering, Northeastern University, Shenyang 110004, China
| | - Jin-Xiang Fu
- School of Municipal and Environmental Engineering, Shenyang Jianzhu University, Shenyang 110168, China
| | - Chuang Liu
- School of Municipal and Environmental Engineering, Shenyang Jianzhu University, Shenyang 110168, China
| | - Rong-Xin Zhang
- School of Municipal and Environmental Engineering, Shenyang Jianzhu University, Shenyang 110168, China; School of Resources and Civil Engineering, Northeastern University, Shenyang 110004, China
| | - Dian-Nan Huang
- School of Municipal and Environmental Engineering, Shenyang Jianzhu University, Shenyang 110168, China
| | - Li Zhang
- School of Municipal and Environmental Engineering, Shenyang Jianzhu University, Shenyang 110168, China.
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Ismail S, Elreedy A, Fujii M, Ni SQ, Tawfik A, Elsamadony M. Fatigue of anammox consortia under long-term 1,4-dioxane exposure and recovery potential: N-kinetics and microbial dynamics. JOURNAL OF HAZARDOUS MATERIALS 2021; 414:125533. [PMID: 34030408 DOI: 10.1016/j.jhazmat.2021.125533] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2020] [Revised: 01/22/2021] [Accepted: 02/23/2021] [Indexed: 06/12/2023]
Abstract
Long-term exposure of anammox process to 1,4-dioxane was investigated using periodic anammox baffled reactor (PABR) under different 1,4-dioxane concentrations. The results generally indicated that PABR (composed of 4 compartments) has robust resistance to 10 mg-dioxane/L. The 1st compartment acted as a shield to protect subsequent compartments from 1,4-dioxane toxicity through secretion of high extracellular polymeric substance (EPS) of 152.9 mg/gVSS at 10 mg-dioxane/L. However, increasing 1,4-dioxane to 50 mg/L significantly inhibited anammox bacteria; e.g., ~ 93% of total nitrogen removal was lost within 14 days. The inhibition of anammox process at this dosage was most likely due to bacterial cell lysis, resulting in the decrease of EPS secretion and specific anammox activity (SAA) to 105.9 mg/gVSS and 0.04 mg N/gVSS/h, respectively, in the 1st compartment. However, anammox bacteria were successfully self-recovered within 41 days after the cease of 1,4-dioxane exposure. The identification of microbial compositions further emphasized the negative impacts of 1,4-dioxane on abundance of C. Brocadia among samples. Furthermore, the development of genus Planococcus in the 1st compartment, where removal of 1,4-dioxane was consistently observed, highlights its potential role as anoxic 1,4-dioxane degrader. Overall, long-term exposure to 1,4-dioxane should be controlled not exceeding 10 mg/L for a successful application.
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Affiliation(s)
- Sherif Ismail
- Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, China; Environmental Engineering Department, Zagazig University, Zagazig 44519, Egypt; Suzhou Research Institute, Shandong University, Suzhou, Jiangsu 215123, China
| | - Ahmed Elreedy
- Sanitary Engineering Department, Alexandria University, Alexandria 21544, Egypt; Department of Applied Biology, Institute for Applied Biosciences, Karlsruhe Institute of Technology, Karlsruhe, Germany
| | - Manabu Fujii
- Civil and Environmental Engineering Department, Tokyo Institute of Technology, Meguro-Ku, Tokyo 152-8552, Japan
| | - Shou-Qing Ni
- Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, China; Suzhou Research Institute, Shandong University, Suzhou, Jiangsu 215123, China.
| | - Ahmed Tawfik
- Water Pollution Research Department, National Research Centre, Giza 12622, Egypt
| | - Mohamed Elsamadony
- Civil and Environmental Engineering Department, Tokyo Institute of Technology, Meguro-Ku, Tokyo 152-8552, Japan; Department of Public Works Engineering, Faculty of Engineering, Tanta University, 31521 Tanta City, Egypt
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7
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He R, Su Y, Leewis MC, Chu YX, Wang J, Ma RC, Wu D, Zhan LT, Herriott IC, Leigh MB. Low O 2 level enhances CH 4-derived carbon flow into microbial communities in landfill cover soils. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 258:113676. [PMID: 31818614 DOI: 10.1016/j.envpol.2019.113676] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2019] [Revised: 07/07/2019] [Accepted: 11/24/2019] [Indexed: 06/10/2023]
Abstract
CH4 oxidation in landfill cover soils plays a significant role in mitigating CH4 release to the atmosphere. Oxygen availability and the presence of co-contaminants are potentially important factors affecting CH4 oxidation rate and the fate of CH4-derived carbon. In this study, microbial populations that oxidize CH4 and the subsequent conversion of CH4-derived carbon into CO2, soil organic C and biomass C were investigated in landfill cover soils at two O2 tensions, i.e., O2 concentrations of 21% ("sufficient") and 2.5% ("limited") with and without toluene. CH4-derived carbon was primarily converted into CO2 and soil organic C in the landfill cover soils, accounting for more than 80% of CH4 oxidized. Under the O2-sufficient condition, 52.9%-59.6% of CH4-derived carbon was converted into CO2 (CECO2-C), and 29.1%-39.3% was converted into soil organic C (CEorganic-C). A higher CEorganic-C and lower CECO2-C occurred in the O2-limited environment, relative to the O2-sufficient condition. With the addition of toluene, the carbon conversion efficiency of CH4 into biomass C and organic C increased slightly, especially in the O2-limited environment. A more complex microbial network was involved in CH4 assimilation in the O2-limited environment than under the O2-sufficient condition. DNA-based stable isotope probing of the community with 13CH4 revealed that Methylocaldum and Methylosarcina had a higher relative growth rate than other type I methanotrophs in the landfill cover soils, especially at the low O2 concentration, while Methylosinus was more abundant in the treatment with both the high O2 concentration and toluene. These results indicated that O2-limited environments could prompt more CH4-derived carbon to be deposited into soils in the form of biomass C and organic C, thereby enhancing the contribution of CH4-derived carbon to soil community biomass and functionality of landfill cover soils (i.e. reduction of CO2 emission).
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Affiliation(s)
- Ruo He
- Zhejiang Provincial Key Laboratory of Solid Waste Treatment and Recycling, School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou, 310012, China; Department of Environmental Engineering, Zhejiang University, Hangzhou, 310058, China.
| | - Yao Su
- Department of Environmental Engineering, Zhejiang University, Hangzhou, 310058, China; Institute of Environment, Resource, Soil and Fertilizer, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - Mary-Cathrine Leewis
- Institute of Arctic Biology, University of Alaska Fairbanks, Alaska, 99775, USA; US Geological Survey, Menlo Park, CA, 94025, USA
| | - Yi-Xuan Chu
- Department of Environmental Engineering, Zhejiang University, Hangzhou, 310058, China
| | - Jing Wang
- Department of Environmental Engineering, Zhejiang University, Hangzhou, 310058, China
| | - Ruo-Chan Ma
- Department of Environmental Engineering, Zhejiang University, Hangzhou, 310058, China
| | - Donglei Wu
- Department of Environmental Engineering, Zhejiang University, Hangzhou, 310058, China
| | - Liang-Tong Zhan
- MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering, Zhejiang University, Hangzhou, 310058, China
| | | | - Mary Beth Leigh
- Institute of Arctic Biology, University of Alaska Fairbanks, Alaska, 99775, USA
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Jiang Y, Yang K, Shang Y, Zhang H, Wei L, Wang H. Response and recovery of aerobic granular sludge to pH shock for simultaneous removal of aniline and nitrogen. CHEMOSPHERE 2019; 221:366-374. [PMID: 30641378 DOI: 10.1016/j.chemosphere.2018.12.207] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2018] [Revised: 11/22/2018] [Accepted: 12/31/2018] [Indexed: 06/09/2023]
Abstract
Considering the pH fluctuation in industrial wastewater, the response and resilience to pH shock should be investigated during aerobic granular sludge (AGS) system operation. In this work, three AGS reactors, namely R1, R2, and R3 for simultaneous removal of aniline and nitrogen were exposed to neutral, acidic, and alkaline conditions, respectively. The removal efficiency of aniline and chemical oxygen demand with pH variation was over 99.9% and 91.0%, respectively after stable in the three reactors. The aniline removal rate modestly decreased in R2 and R3 after pH varied and denitrification was slightly improved in acidic environment with average removal efficiency of 61.2%. The mature AGS could maintain settleability in R1 and R2 with 30 min sludge volume index below 35 mL g-1 but was unstable under alkaline condition. Correspondingly, the secretion of extracellular polymeric substances especially protein decreased notably in R3. The bacterial groups varied with pH shock, but some could recover after adjustment to original pH value. Proteobacteria was the predominant phylum in the three reactors and Bacteroidetes was enriched in alkaline conditions. In addition, the main functional genera such as Achromobacter, Defluviimonas, Enterobacter, Pseudomonas, and Pseudoxanthomonas, were detected in the system and were found to be responsible for reduction of aniline and nitrogen.
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Affiliation(s)
- Yu Jiang
- School of Civil Engineering, Wuhan University, Wuhan 430072, China
| | - Kai Yang
- School of Civil Engineering, Wuhan University, Wuhan 430072, China
| | - Yu Shang
- School of Civil Engineering, Wuhan University, Wuhan 430072, China
| | - Huining Zhang
- School of Civil Engineering, Lanzhou University of Technology, Lanzhou 730000, China
| | - Li Wei
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Hongyu Wang
- School of Civil Engineering, Wuhan University, Wuhan 430072, China.
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He R, Su Y, Ma RC, Zhuang S. Characterization of toluene metabolism by methanotroph and its effect on methane oxidation. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:16816-16824. [PMID: 29616477 DOI: 10.1007/s11356-018-1863-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 03/26/2018] [Indexed: 06/08/2023]
Abstract
Methanotrophs not only oxidize CH4, but also can oxidize a relatively broad range of other substrates, including trichloroethylene, alkanes, alkenes, and aromatic compounds. In this study, Methylosinus sporium was used as a model organism to characterize toluene metabolism by methanotrophs. Reverse transcription quantitative PCR analysis showed that toluene enhanced the mmoX expression of M. sporium. When the toluene concentration was below 2000 mg m-3, the kinetics of toluene metabolism by M. sporium conformed to the Michaelis-Menten equation (Vmax = 0.238 g gdry weight-1 h-1, K m = 545.2 mg m-3). The use of a solid-phase extraction technique followed by a gas chromatography-mass spectrometry analysis and molecular docking calculation showed that toluene was likely to primarily bind the di-iron center structural region of soluble methane monooxygenase (sMMO) hydroxylase and then be oxidized to o-cresol. Although M. sporium oxidized toluene, it did not incorporate toluene into its biomass. The coexistence of toluene and CH4 could influence CH4 oxidation, the growth of methanotrophs, and the distribution of CH4-derived carbon, which were related to the ratio of the toluene concentration to biomass. These results would be helpful to understand the metabolism of CH4 and non-methane volatile organic compounds in the environment.
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Affiliation(s)
- Ruo He
- Department of Environmental Engineering, Zhejiang University, Hangzhou, 310058, China.
| | - Yao Su
- Department of Environmental Engineering, Zhejiang University, Hangzhou, 310058, China
- Institute of Environment, Resource, Soil and Fertilizer, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - Ruo-Chan Ma
- Department of Environmental Engineering, Zhejiang University, Hangzhou, 310058, China
| | - Shulin Zhuang
- Institute of Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China
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