This family includes a region of the large protein pyruvate-flavodoxin oxidoreductase and the whole pyruvate ferredoxin oxidoreductase gamma subunit protein. It is not known whether the gamma subunit has a catalytic or regulatory role. Pyruvate oxidoreductase (POR) catalyses the final step in the fermentation of carbohydrates in anaerobic microorganisms [1]. This involves the oxidative decarboxylation of pyruvate with the participation of thiamine followed by the transfer of an acetyl moiety to coenzyme A for the synthesis of acetyl-CoA [1]. The family also includes pyruvate flavodoxin oxidoreductase as encoded by the nifJ gene in cyanobacterium which is required for growth on molecular nitrogen when iron is limited [2].

1: Molecular and phylogenetic characterization of pyruvate and 2-ketoisovalerate ferredoxin oxidoreductases from Pyrococcus furiosus and pyruvate ferredoxin oxidoreductase from Thermotoga maritima. Kletzin A, Adams MW; J Bacteriol 1996;178:248-257. PMID:8550425

2: Growth of the cyanobacterium Anabaena on molecular nitrogen: NifJ is required when iron is limited. Bauer CC, Scappino L, Haselkorn R; Proc Natl Acad Sci U S A 1993;90:8812-8816. PMID:8415612