title: Spatial distribution of bacterial communities on volumetric and planar anodes in single-chamber air-cathode microbial fuel cells.
abstract: Pyrosequencing was used to characterize bacterial communities in air-cathode microbial fuel cells across a volumetric (graphite fiber brush) and a planar (carbon cloth) anode, where different physical and chemical gradients would be expected associated with the distance between anode location and the air cathode. As expected, the stable operational voltage and the coulombic efficiency (CE) were higher for the volumetric anode than the planar anode (0.57 V and CE = 22% vs. 0.51 V and CE = 12%). The genus Geobacter was the only known exoelectrogen among the observed dominant groups, comprising 57 ± 4% of recovered sequences for the brush and 27 ± 5% for the carbon-cloth anode. While the bacterial communities differed between the two anode materials, results showed that Geobacter spp. and other dominant bacterial groups were homogenously distributed across both planar and volumetric anodes. This lends support to previous community analysis interpretations based on a single biofilm sampling location in these systems.
authors.affiliation: Department of Civil and Environmental Engineering, The Pennsylvania State University, University Park, Pennsylvania; Department of Hydraulic and Environmental Engineering, Pontificia Universidad Católica de Chile, Santiago, Chile.
authors.forename: Ignacio T
authors.initials: IT
authors.lastname: Vargas
authors.forename: Istvan U
authors.initials: IU
authors.lastname: Albert
authors.forename: John M
authors.initials: JM
authors.lastname: Regan
mesh_terms: D000388:Air; D001419:Bacteria / Q000145:classification* / Q000235:genetics*; D001674:Bioelectric Energy Sources; D058448:Biota; D002244:Carbon; D004566:Electrodes / Q000382:microbiology*; D017422:Sequence Analysis, DNA
chemical_list: D002244:Carbon
keywords: MFC; anodic community; pyrosequencing