This cytochrome P450 monooxygenase plays a critical role in the metabolism of sterols, steroid hormones, retinoids, fatty acids, and xenobiotics. Mechanistically, it utilizes molecular oxygen to insert one oxygen atom into substrates while reducing the other into water, powered by NADPH via cytochrome P450 reductase. It catalyzes hydroxylation of carbon-hydrogen bonds and exhibits high activity for producing hydroxyestrogens from estrone (E1) and 17beta-estradiol (E2), including 2-hydroxy E1/E2 and D-ring hydroxylated E1/E2 at the C-16 position.
In androgen metabolism, it deactivates testosterone by converting it to 2beta- and 6beta-hydroxytestosterones. It also contributes to cholesterol degradation and bile acid biosynthesis by forming hydroxycholesterols, such as 4beta- and 25-hydroxycholesterol. Additionally, it metabolizes polyunsaturated fatty acids (PUFA) via bisallylic hydroxylation and epoxidation of double bonds, preferring the terminal double bond. In the endocannabinoid system, it converts arachidonoylethanolamide (anandamide) into epoxyeicosatrienoic acid ethanolamides (EpETrE-EAs), potentially modulating signaling.
The enzyme plays a vital role in retinoid metabolism, oxidizing all-trans-retinol to all-trans-retinal, a key step in all-trans-retinoic acid biosynthesis, and further metabolizing retinoic acid for hepatic clearance. It is involved in drug metabolism, catalyzing reactions for albendazole, fenbendazole, quinine, and 1,8-cineole. Additionally, it regulates vitamin D catabolism by inactivating calcitriol, contributing to calcium homeostasis.
| Product Name | Recombinant Human Cytochrome P450 3A4/CYP3A4 Protein |
| Accession | P08684 |
| Host Species | Human |
| Gene | CYP3A4 |
| Source | Wheat germ |
