Structure and mechanism of the flavocytochrome c fumarate reductase of Shewanella putrefaciens MR-1.
Leys, D., Tsapin, A.S., Nealson, K.H., Meyer, T.E., Cusanovich, M.A., Van Beeumen, J.J.(1999) Nat Struct Biol 6: 1113-1117
- PubMed: 10581551 
- DOI: https://doi.org/10.1038/70051
- Primary Citation of Related Structures:  
1D4C, 1D4D, 1D4E - PubMed 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.
Organizational Affiliation: 
Laboratory of Protein Biochemistry and Protein Engineering, Department of Biochemistry, Physiology and Microbiology, K.L. Ledeganckstraat 35, 9000 Gent, Belgium.