cytochrome P450 family 1, subfamily D, polypeptide 1
The cytochrome P450 1D1 (CYP1D1) gene is pseudogenized in humans because of five nonsense mutations in the putative coding region. However, in other organisms including cynomolgus monkey, CYP1D1 is a functional drug-metabolizing enzyme that is highly expressed in the liver. CYP1D1 belongs to the large cytochrome P450 (P450, CYP) superfamily of heme-containing proteins that catalyze a variety of oxidative reactions of a large number of structurally different endogenous and exogenous compounds in organisms from all major domains of life. CYPs bind their diverse ligands in a buried, hydrophobic active site, which is accessed through a substrate access channel formed by two flexible helices and their connecting loop.