Pyruvate-flavodoxin oxidoreductase (IPR011895)

Short name: Pyrv_flavodox_OxRed

Overlapping homologous superfamilies

Family relationships



The oxidative decarboxylation of pyruvate to acetyl-CoA, a central step in energy metabolism, can occur by two different mechanisms [PMID: 10607667]. In mitochondria and aerobic bacteria this reaction is catalysed by the multienzyme complex pyruvate dehydrogenase using NAD as electron acceptor. In anaerobic organisms, however, this reaction is reversibly catalysed by a single enzyme using either ferrodoxin or flavodoxin as the electron acceptor.

Pyruvate:ferrodoxin/flavodoxin reductases (PFORs) in this entry occur in both obligately and facultatively anaerobic bacteria and also some eukaryotic microorganisms. These proteins are single-chain enzymes containing a thiamin pyrophosphate cofactor for the cleavage of carbon-carbon bonds next to a carbonyl group, and iron-sulphur clusters for electron transfer. The Desulfovibrio africanus enzyme is currently the only PFOR whose three dimensional structure is known [PMID: 10048931, PMID: 11752578]. It is a homodimer where each subunit contains one thiamin pyrophosphate cofactor and two ferrodoxin-like 4Fe-S clusters and an atypical 4Fe-S cluster. Each monomer is composed of seven domains - domains I, II and VI make intersubunit contacts, while domains III, IV and V are located at the surface of the dimer, and domain VII forms a long arm extending over the other subunit. The cofactor is bound at the interface of domains I and VI and is proximal to the atypical 4Fe-S bound by domain VI, while the ferrodoxin-like 4Fe-S clusters are bound by domain V. Comparison of this enzyme with the multi-chain PFORs shows a correspondence between the domains in this enzyme and the subunits of the multi-chain enzymes.

GO terms

Biological Process

GO:0022900 electron transport chain
GO:0055114 oxidation-reduction process

Molecular Function

GO:0005506 iron ion binding
GO:0016903 oxidoreductase activity, acting on the aldehyde or oxo group of donors

Cellular Component

No terms assigned in this category.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.