Sterol 14-demethylase

In enzymology, a sterol 14-demethylase is an enzyme that catalyzes the chemical reaction


 * obtusifoliol + 3 O2 + 3 NADPH + 3 H+ $$\rightleftharpoons$$ 4alpha-methyl-5alpha-ergosta-8,14,24(28)-trien-3beta-ol + formate + 3 NADP+ + 4 H2O

The 4 substrates of this enzyme are obtusifoliol, O2, NADPH, and H+, whereas its 4 products are 4alpha-methyl-5alpha-ergosta-8,14,24(28)-trien-3beta-ol, formate, 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 sterol,NADPH:oxygen oxidoreductase (14-methyl cleaving). Other names in common use include obtusufoliol 14-demethylase, lanosterol 14-demethylase, lanosterol 14alpha-demethylase, and sterol 14alpha-demethylase. This enzyme participates in biosynthesis of steroids.

Structural studies
As of late 2007, 6 structures have been solved for this class of enzymes, with PDB accession codes, , , , , and.