Microbial reduction of tellurate by an enriched consortium performing anaerobic oxidation of methane in a sequencing batch reactor

Abstract

Anaerobic oxidation of methane (AOM) is capable of coupling the reduction of various substrates, which plays a crucial role in accelerating the abatement of pollution. In this study, we employed a sequencing batch reactor (SBR) to enrich a mixed consortium that included AOM microbes and examined the ensuing microbial reduction of tellurate. To obtain the mixed consortium, we enriched AOM microbes in anaerobic conditions utilizing methane as the only electron donor, with nitrate serving as the electron acceptor. We evaluated the abundance of typical methane-oxidizing microbes and associated genes in the reactor using quantitative PCR. Notably, the enriched microbes were able to achieve microbial tellurate reduction and produce elemental tellurium. An analysis of community structure further indicated the vital roles of methanotrophs, denitrifiers, and other heterotrophs in the reactor, although their molecular mechanisms require further investigation. These findings underscore the role of enriched microbial communities in tellurate reduction using a lab-scale SBR, laying the groundwork for future studies into the mechanism of this process, which utilizes methane as an electron donor.