Protoheme IX farnesyltransferase (also called heme O synthase, heme A:farnesyltransferase, cytochrome c oxidase subunit X [Cox10]) converts heme B (protoheme IX) to heme O by substitution of the vinyl group on carbon 2 of the heme B porphyrin ring with a hydroxyethyl farnesyl side group. It is localized at the mitochondrial inner membrane. Eukaryotic Cox10 is important for the maturation of the heme A prosthetic group of cytochrome c oxidase (COX), the terminal component of the mitochondrial respiratory chain, that catalyzes the electron transfer from reduced cytochrome c to oxygen. Prenyltransferases (PTs) catalyze the regioselective transfer of prenyl moieties onto a wide variety of substrates and play an important role in many biosynthetic pathways.
Feature 1: putative active site [active site], 3 residue positions
Conserved feature residue pattern:[eD] D D
Evidence:
Comment:based on homology modeling using structures of trans prenyltransferases that are helical enzymes containing two D-rich motifs in the active site