Cytochrome P450 39A1 (CYP39A1)

CYP39A1 is a member of the cytochrome P450 superfamily of enzymes. The cytochrome P450 proteins are monooxygenases which catalyze many reactions involved in drug metabolism and synthesis of cholesterol, steroids and other lipids. This endoplasmic reticulum protein is involved in the conversion of cholesterol to bile acids. Its substrates include the oxysterols 24-hydroxycholesterol, 25-hydroxycholesterol and 27-hydroxycholesterol.By EST database searching and RT-PCR, they isolated human CYP39A1 which encodes a deduced 469-amino acid protein that shares 75% sequence identity with its mouse counterpart. The protein has features of a microsomal cytochrome P450 enzyme, including a hydrophobic N terminus and an invariant cysteine residue located toward the C terminus.