Current production by non-methanotrophic bacteria enriched from an anaerobic methane-oxidizing microbial community

In recent years, the externalization of electrons as part respiratory metabolic processes has been discovered in many different bacteria and some archaea. Microbial extracellular electron transfer (EET) plays an important role anoxic natural or engineered ecosystems. this study, anaerobic methane-converting microbial community was investigated with regard to its potential perform EET. At point, it is not well-known if how EET confers a competitive advantage certain species communities. two-chamber electrochemical system, sparged methane applied +400 mV versus standard hydrogen electrode. A biofilm developed on working electrode stable low-density current produced, confirming that indeed did occur. The appearance presence redox centers at −140 −160 −230 confirmed by cyclic voltammetry scans. Metagenomic analysis fluorescence situ hybridization showed methanotroph ‘Candidatus Methanoperedens BLZ2’ significant member community, but relative abundance increase compared inoculum. On contrary, other members significantly increased (up 720-fold, 7.2% mapped reads), placing these microorganisms among dominant bioanode community. This group included Zoogloea sp., Dechloromonas two Bacteroidetes phylum, spirochete Leptonema sp. Genes encoding proteins putatively involved were identified one phylum. We suggest instead methane, alternative carbon sources such acetate substrate for Hence, methane-driven chemolithoautotrophic seems complex process which interactions within are driving