PMID: 10581551 , Related PDB ids: 1D4C, 1D4D, 1D4E

Authors:

Leys D, Tsapin AS, Nealson KH, Meyer TE, Cusanovich MA, Van Beeumen JJ

Title:

Structure and mechanism of the flavocytochrome c fumarate reductase of Shewanella putrefaciens MR-1.

Journal:

Nat Struct Biol. 1999 Dec;6(12):1113-7.

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.