Thiamine pyrophosphate (TPP family), PFOR porB-like subfamily, TPP-binding module; composed of proteins similar to the beta subunit (porB) of the Helicobacter pylori four-subunit pyruvate ferredoxin oxidoreductase (PFOR), which are also found in archaea and some hyperthermophilic bacteria. PFOR catalyzes the oxidative decarboxylation of pyruvate to form acetyl-CoA, a crucial step in many metabolic pathways. Archaea, anaerobic bacteria and eukaryotes that lack mitochondria (and therefore pyruvate dehydrogenase) use PFOR to oxidatively decarboxylate pyruvate, with ferredoxin or flavodoxin as the electron acceptor. The 36-kDa porB subunit contains the binding sites for the cofactors, TPP and a divalent metal cation, which are required for activity.
Jiyao W et al.(2023). "The conserved domain database in 2023.",