title: Structure and mechanism of the flavocytochrome c fumarate reductase of Shewanella putrefaciens MR-1.
abstract: Fumarate respiration is one of the most widespread types of anaerobic respiration. The soluble fumarate reductase of Shewanella putrefaciens MR-1 is a periplasmic tetraheme flavocytochrome c. The crystal structures of the enzyme were solved to 2.9 A for the uncomplexed form and to 2.8 A and 2.5 A for the fumarate and the succinate-bound protein, respectively. The structures reveal a flexible capping domain linked to the FAD-binding domain. A catalytic mechanism for fumarate reduction based on the structure of the complexed protein is proposed. The mechanism for the reverse reaction is a model for the homologous succinate dehydrogenase (complex II) of the respiratory chain. In flavocytochrome c fumarate reductase, all redox centers are in van der Waals contact with one another, thus providing an efficient conduit of electrons from the hemes via the FAD to fumarate.
authors.affiliation: Laboratory of Protein Biochemistry and Protein Engineering, Department of Biochemistry, Physiology and Microbiology, K.L. Ledeganckstraat 35, 9000 Gent, Belgium.
authors.forename: D
authors.initials: D
authors.lastname: Leys
authors.forename: A S
authors.initials: AS
authors.lastname: Tsapin
authors.forename: K H
authors.initials: KH
authors.lastname: Nealson
authors.forename: T E
authors.initials: TE
authors.lastname: Meyer
authors.forename: M A
authors.initials: MA
authors.lastname: Cusanovich
authors.forename: J J
authors.initials: JJ
authors.lastname: Van Beeumen
mesh_terms: D000594:Amino Acid Oxidoreductases / Q000737:chemistry; D000595:Amino Acid Sequence; D001665:Binding Sites; D020134:Catalytic Domain; D003460:Crystallization; D018360:Crystallography, X-Ray; D003574:Cytochrome c Group / Q000737:chemistry* / Q000378:metabolism*; D004583:Electrons; D004926:Escherichia coli / Q000201:enzymology; D029968:Escherichia coli Proteins; D005182:Flavin-Adenine Dinucleotide / Q000378:metabolism; D005650:Fumarates / Q000737:chemistry / Q000378:metabolism; D006418:Heme / Q000737:chemistry / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000737:chemistry* / Q000378:metabolism*; D017510:Protein Folding; D017433:Protein Structure, Secondary; D020614:Shewanella putrefaciens / Q000201:enzymology*; D013385:Succinate Dehydrogenase / Q000737:chemistry* / Q000378:metabolism*; D019802:Succinic Acid / Q000737:chemistry / Q000378:metabolism
chemical_list: D003574:Cytochrome c Group; D029968:Escherichia coli Proteins; D005650:Fumarates; D005182:Flavin-Adenine Dinucleotide; D006418:Heme; C032005:fumaric acid; D019802:Succinic Acid; D010088:Oxidoreductases; D013385:Succinate Dehydrogenase; D000594:Amino Acid Oxidoreductases; C031955:L-aspartate oxidase, E coli; C064500:flavocytochrome c sulfide dehydrogenase