Nitrite-driven anaerobic ethane oxidation  

作　　者：Cheng-Cheng Dang Yin-Zhu Jin Xin Tan Wen-Bo Nie Yang Lu Bing-Feng Liu De-Feng Xing Nan-Qi Ren Guo-Jun Xie 

机构地区：[1]State Key Laboratory of Urban Water Resource and Environment,School of Environment,Harbin Institute of Technology,Harbin,150090,China [2]Key Laboratory of the Three Gorges Region's Eco-Environment,Ministry of Education,College of Environment and Ecology,Chongqing University,Chongqing,400044,China [3]Water Innovation and Smart Environment Laboratory,School of Civil and Environmental Engineering,Faculty of Engineering,Queensland University of Technology,Brisbane,Queensland,4001,Australia

出　　处：《Environmental Science and Ecotechnology》2024年第5期361-368,共8页环境科学与生态技术（英文）

基　　金：The authors would like to thank the Natural Science Foundation of China(Grant No.52270032);the Fundamental Research Funds for the Central Universities(Grant No.HIT.BRET.2021014);the Fok Ying Tung Education Foundation,State Key Laboratory of Urban Water Resource and Environment,Harbin Institute of Technology(2023DX09);the Heilongjiang Nature Science Foundation(YQ2021E028);Heilongjiang Touyan Innovation Team Program for supporting this study.

摘　　要：Ethane,the second most abundant gaseous hydrocarbon in vast anoxic environments,is an overlooked greenhouse gas.Microbial anaerobic oxidation of ethane can be driven by available electron acceptors such as sulfate and nitrate.However,despite nitrite being a more thermodynamically feasible electron acceptor than sulfate or nitrate,little is known about nitrite-driven anaerobic ethane oxidation.In this study,a microbial culture capable of nitrite-driven anaerobic ethane oxidation was enriched through the long-term operation of a nitrite-and-ethane-fed bioreactor.During continuous operation,the nitrite removal rate and the theoretical ethane oxidation rate remained stable at approximately 25.0 mg NO_(2) eN L^(-1) d^(-1) and 11.48 mg C2H6 L^(-1) d^(-1),respectively.Batch tests demonstrated that ethane is essential for nitrite removal in this microbial culture.Metabolic function analysis revealed that a species affiliated with a novel genus within the family Rhodocyclaceae,designated as'Candidatus Alkanivoras nitrosoreducens',may perform the nitrite-driven anaerobic ethane oxidation.In the proposed metabolic model,despite the absence of known genes for ethane conversion to ethyl-succinate and succinate-CoA ligase,'Ca.A.nitrosoreducens'encodes a prospective fumarate addition pathway for anaerobic ethane oxidation and a complete denitrification pathway for nitrite reduction to nitrogen.These findings advance our understanding of nitrite-driven anaerobic ethane oxidation,highlighting the previously overlooked impact of anaerobic ethane oxidation in natural ecosystems.

关 键 词：Anaerobic ethane oxidation DENITRIFICATION Microbial culture Fumarate addition pathway Greenhouse gas 

分 类 号：X701[环境科学与工程—环境工程]