title: Decoupling of DAMO archaea from DAMO bacteria in a methane-driven microbial fuel cell.
abstract: Anaerobic oxidation of methane (AOM) contributes significantly to the global methane sink. Previously, studies of anaerobic methanotrophic (ANME) archaea have been limited as they have not been separable from their bacterial partners during the AOM process because of their dependence on the bacteria. A microbial fuel cell (MFC) is a device capable of directly transforming chemical energy to electrical energy via electrochemical reactions involving biochemical pathways. In this study, decoupling of denitrifying anaerobic methane oxidation (DAMO) archaea and DAMO bacteria was investigated in an microbial fuel cell (MFC) using methane as the fuel. The DAMO fuel cell worked successfully but demonstrated weak electrogenic capability with around 25 mV production. After 45 days' enrichment, the sequencing and fluorescence in situ hybridization results showed the DAMO archaea percentage had increased from 26.96% (inoculum) to 65.77% (electrode biofilm), while the DAMO bacteria percentage decreased from 24.39% to 2.07%. Moreover, the amount of ANME-2d had doubled in the electrode biofilm compared with the inoculum. The sequencing results also showed substantial enrichment of the Ignavibacterium and Geobacter genera. The roles of Ignavibacterium and Geobacter in the MFC system need to be further investigated. Nevertheless, these results illustrate that an MFC device may provide a possible approach to separate DAMO archaea from DAMO bacteria.
authors.affiliation: Advanced Laboratory for Environmental Research and Technology, USTC-CityU, Suzhou 215123, PR China.
authors.forename: Jing
authors.initials: J
authors.lastname: Ding
authors.affiliation: CAS Key Laboratory for Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei 230026, PR China.
authors.forename: Yong-Ze
authors.initials: YZ
authors.lastname: Lu
authors.affiliation: CAS Key Laboratory for Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei 230026, PR China.
authors.forename: Liang
authors.initials: L
authors.lastname: Fu
authors.affiliation: CAS Key Laboratory for Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei 230026, PR China.
authors.forename: Zhao-Wei
authors.initials: ZW
authors.lastname: Ding
authors.affiliation: CAS Key Laboratory for Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei 230026, PR China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Mu
authors.affiliation: Advanced Laboratory for Environmental Research and Technology, USTC-CityU, Suzhou 215123, PR China; State Key Laboratory in Marine Pollution, Department of Biomedical Science, City University of Hong Kong, Kowloon, Hong Kong.
authors.forename: Shuk H
authors.initials: SH
authors.lastname: Cheng
authors.affiliation: Advanced Laboratory for Environmental Research and Technology, USTC-CityU, Suzhou 215123, PR China; CAS Key Laboratory for Urban Pollutant Conversion, Department of Chemistry, University of Science and Technology of China, Hefei 230026, PR China. Electronic address: rzeng@ustc.edu.cn.
authors.forename: Raymond J
authors.initials: RJ
authors.lastname: Zeng
mesh_terms: D000693:Anaerobiosis; D001105:Archaea / Q000235:genetics*; D001419:Bacteria / Q000378:metabolism; D001674:Bioelectric Energy Sources; D017404:In Situ Hybridization, Fluorescence; D008697:Methane / Q000378:metabolism; D008772:Methylococcaceae / Q000378:metabolism*; D010084:Oxidation-Reduction
chemical_list: D008697:Methane
keywords: ANME-2d archaea; Anaerobic oxidation of methane (AOM); Decoupling; Denitrifying anaerobic methane oxidation (DAMO); Methane-driven MFC; Purification