Cholesterol 24-hydroxylase

In enzymology, a cholesterol 24-hydroxylase is an enzyme that catalyzes the chemical reaction


 * cholesterol + NADPH + H+ + O2 $$\rightleftharpoons$$ (24S)-24-hydroxycholesterol + NADP+ + H2O

The 4 substrates of this enzyme are cholesterol, NADPH, H+, and O2, whereas its 3 products are (24S)-24-hydroxycholesterol, NADP+, and H2O.

This enzyme belongs to the family of oxidoreductases, specifically those acting on paired donors, with O2 as oxidant and incorporation or reduction of oxygen. The oxygen incorporated need not be derived from O2 with NADH or NADPH as one donor, and incorporation of one atom o oxygen into the other donor. The systematic name of this enzyme class is cholesterol,NADPH:oxygen oxidoreductase (24-hydroxylating). Other names in common use include cholesterol 24-monooxygenase, CYP46, CYP46A1, cholesterol 24S-hydroxylase, and cytochrome P450 46A1.