The electric picnic: synergistic requirements for exoelectrogenic microbial communities

Characterization of the various microbial populations present in exoelectrogenic biofilms provides insight into the processes required to convert complex organic matter in wastewater streams into electrical current in bioelectrochemical systems (BESs). Analysis of the community profiles of exoelectrogenic microbial consortia in BESs fed different substrates gives a clearer picture of the different microbial populations present in these exoelectrogenic biofilms. Rapid utilization of fermentation end products by exoelectrogens (typically Geobacter species) relieves feedback inhibition for the fermentative consortia, allowing for rapid metabolism of organics. Identification of specific syntrophic processes and the communities characteristic of these anodic biofilms will be a valuable aid in improving the performance of BESs.

► Improved BES performance will be aided by a more complete understanding of the exoelectrogenic microbial partners.
► Synergistic microbial communities are required for the conversion of complex organics into electrical current in BESs.
► Geobacter sp. are identified as the dominant exoelctrogenic partners in the majority of community profiling studies.
► The rapid removal of fermentation by-products by exoectogenic partners can remove feed-back inhibition of complex organics.