CYP51 (Yeast)

Sterol 14alpha-demethylase that plays a critical role in the third module of ergosterol biosynthesis pathway, being ergosterol the major sterol component in fungal membranes that participates in a variety of functions (PubMed:369554, PubMed:105731). The third module or late pathway involves the ergosterol synthesis itself through consecutive reactions that mainly occur in the endoplasmic reticulum (ER) membrane (PubMed:32679672). Starting from lanosterol (lanosta-8,24-dien-3beta-ol), it catalyzes the three-step oxidative removal of the 14alpha-methyl group (C-32) of the sterol in the form of formate, and converts the sterol to 4,4-dimethyl-5alpha-cholesta-8,14,24-trien-3beta-ol, which is critical for ergosterol biosynthesis (PubMed:369554, PubMed:105731, PubMed:3543000). Can demethylate susbtrates not intrinsic to yeast, such as eburicol (24-methylene-24,25-dihydrolanosterol) at a similar rate to lanosterol, and at a lower rate the 24,25-dihydrolanosterol (DHL) to 4,4-dimethyl-8,14-cholestadien-3beta-ol (PubMed:3543000, PubMed:1872829).