Title:
Cellular activities contextualized by microbial neighborhoods and implications for syntrophic intermediates during anaerobic methane oxidation.

Abstract:
Archaea-bacteria consortia responsible for anaerobic methane oxidation are examples of naturally occurring syntrophic consortia which reside in a low energy environment. I'll present nanoSIMS data acquired on thousands of individual cells from this ecosystem which are inconsistent with models of syntrophy based on the passage of a diffusible intermediate, but are instead suggestive of syntrophic coupling through direct interspecies electron transfer as a mechanism for relaxing spatial constraints associated with diffusive exchange. In support of this hypothesis, we found that redox activity was located inbetween individual cells in consortia, and also identified a putative protein to account for cell-surface conductivity. To summarize these observations, I will present a new model of methane oxidizing archaea metabolism based on direct extracellular electron transfer which would help explain our new data.