title: High-affinity binding and direct electron transfer to solid metals by the Shewanella oneidensis MR-1 outer membrane c-type cytochrome OmcA.
abstract: The purified outer membrane bacterial protein OmcA binds densely to the surface of hematite (Fe2O3), permitting direct electron transfer to this solid mineral to reduce Fe (III) with an electron flux of about 1013 electrons /cm2/s. In the presence of hematite, there is a substantial increase in the amplitude of internal protein motions that correlate with metal reduction. Binding is highly favorable, with a partition coefficient of approximately 2 x 105 (DeltaGo' = -28 kJ/mol), where approximately 1014 OmcA proteins bind per cm2 to the solid metal surface, indicating the utility of using purified OmcA in the construction of a biofuel cell.
authors.affiliation: Division of Biological Sciences and Environmental Molecular Science Laboratory, Biogeochemistry Grand Challenge Program, Pacific Northwest National Laboratory, Richland, WA 99352, USA.
authors.forename: Yijia
authors.initials: Y
authors.lastname: Xiong
authors.forename: Liang
authors.initials: L
authors.lastname: Shi
authors.forename: Baowei
authors.initials: B
authors.lastname: Chen
authors.forename: M Uljana
authors.initials: MU
authors.lastname: Mayer
authors.forename: Brian H
authors.initials: BH
authors.lastname: Lower
authors.forename: Yuri
authors.initials: Y
authors.lastname: Londer
authors.forename: Saumyaditya
authors.initials: S
authors.lastname: Bose
authors.forename: Michael F
authors.initials: MF
authors.lastname: Hochella
authors.forename: James K
authors.initials: JK
authors.lastname: Fredrickson
authors.forename: Thomas C
authors.initials: TC
authors.lastname: Squier
mesh_terms: D001426:Bacterial Proteins / Q000737:chemistry / Q000378:metabolism*; D045304:Cytochromes c / Q000737:chemistry / Q000378:metabolism*; D008565:Membrane Proteins / Q000737:chemistry / Q000378:metabolism*; D008670:Metals / Q000378:metabolism*; D011485:Protein Binding; D020592:Shewanella / Q000201:enzymology*; D013050:Spectrometry, Fluorescence
chemical_list: D001426:Bacterial Proteins; D008565:Membrane Proteins; D008670:Metals; D045304:Cytochromes c