title: Extracellular electron transport-mediated Fe(III) reduction by a community of alkaliphilic bacteria that use flavins as electron shuttles.
abstract: The biochemical and molecular mechanisms used by alkaliphilic bacterial communities to reduce metals in the environment are currently unknown. We demonstrate that an alkaliphilic (pH > 9) consortium dominated by Tissierella, Clostridium, and Alkaliphilus spp. is capable of using iron (Fe(3+)) as a final electron acceptor under anaerobic conditions. Iron reduction is associated with the production of a freely diffusible species that, upon rudimentary purification and subsequent spectroscopic, high-performance liquid chromatography, and electrochemical analysis, has been identified as a flavin species displaying properties indistinguishable from those of riboflavin. Due to the link between iron reduction and the onset of flavin production, it is likely that riboflavin has an import role in extracellular metal reduction by this alkaliphilic community.
authors.affiliation: School of Civil Engineering, University of Leeds, Leeds, United Kingdom.
authors.forename: Samuel J
authors.initials: SJ
authors.lastname: Fuller
authors.forename: Duncan G G
authors.initials: DG
authors.lastname: McMillan
authors.forename: Marc B
authors.initials: MB
authors.lastname: Renz
authors.forename: Martin
authors.initials: M
authors.lastname: Schmidt
authors.forename: Ian T
authors.initials: IT
authors.lastname: Burke
authors.forename: Douglas I
authors.initials: DI
authors.lastname: Stewart
mesh_terms: D002853:Chromatography, Liquid; D004563:Electrochemistry; D004579:Electron Transport; D005290:Ferric Compounds / Q000378:metabolism*; D005415:Flavins / Q000378:metabolism*; D059013:Microbial Consortia; D008969:Molecular Sequence Data; D010084:Oxidation-Reduction; D017422:Sequence Analysis, DNA; D013057:Spectrum Analysis
chemical_list: D005290:Ferric Compounds; D005415:Flavins