Methane-Linked Mechanisms of Electron Uptake from Cathodes by Methanosarcina barkeri

Methanogenic archaea are of fundamental applied and environmental relevance. This is largely due to their activities in a wide range of anaerobic environments, generating gaseous reduced carbon that can be utilized as a fuel source. While the bioenergetics of a wide variety of methanogens have been well studied with respect to soluble substrates, a mechanistic understanding of their interaction with solid-phase redox-active compounds is limited. This work provides insight into solid-phase redox interactions in Methanosarcina spp. using electrochemical methods. We highlight a previously undescribed mode of electron uptake from cathodes that is potentially informative of direct interspecies electron transfer interactions in the Methanosarcinales .