title: Influence of inoculum and anode surface properties on the selection of Geobacter-dominated biofilms.
abstract: This study evaluated the impact of inoculum source and anode surface modification (carboxylate -COO(-) and sulfonamide -SO2NH2 groups) on the microbial composition of anode-respiring biofilms. These two factors have not previously been considered in detail. Three different inoculum sources were investigated, a dry aerobic soil, brackish estuarine mud and freshwater sediment. The biofilms were selected using a poised anode (-0.36 V vs Ag/AgCl) and acetate as the electron donor in a three-electrode configuration microbial fuel cell (MFC). Population profiling and cloning showed that all biofilms selected were dominated by Geobacter sp., although their electrochemical properties varied depending on the source inoculum and electrode surface modification. These findings suggest that Geobacter sp. are widespread in soils, even those that do not provide a continuously anaerobic environment, and are better at growing in the MFC conditions than other bacteria.
authors.affiliation: Lincoln Agritech Ltd., Engineering Drive, Lincoln University, Christchurch 7640, New Zealand. Electronic address: audrey.commault@gmail.com.
authors.forename: Audrey S
authors.initials: AS
authors.lastname: Commault
authors.affiliation: Institut des Sciences Chimiques de Rennes, UMR CNRS 6226, Université de Rennes 1, France.
authors.forename: Frédéric
authors.initials: F
authors.lastname: Barrière
authors.affiliation: Institut des Sciences Chimiques de Rennes, UMR CNRS 6226, Université de Rennes 1, France.
authors.forename: Laure
authors.initials: L
authors.lastname: Lapinsonnière
authors.affiliation: School of Biological Sciences, The University of Auckland, Auckland 1010, New Zealand.
authors.forename: Gavin
authors.initials: G
authors.lastname: Lear
authors.affiliation: Ecole Nationale Supérieure de Chimie et de Physique de Bordeaux, France.
authors.forename: Solène
authors.initials: S
authors.lastname: Bouvier
authors.affiliation: Lincoln Agritech Ltd., Engineering Drive, Lincoln University, Christchurch 7640, New Zealand.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Weld
mesh_terms: D001674:Bioelectric Energy Sources / Q000382:microbiology; D018441:Biofilms; D004560:Electricity; D004566:Electrodes; D045302:Geobacter / Q000502:physiology*; D013499:Surface Properties
keywords: Electroactive biofilm; Electrode surface; Microbial fuel cell; Population profiling; Soils