Human Cytochrome P450 11B1, Mitochondrial, CYP11B1 ELI

A cytochrome P450 monooxygenase involved in the biosynthesis of adrenal corticoids (PubMed: 18215163).

Catalyzes the hydroxylation of carbon hydrogen bond at 11-beta position of 11-deoxycortisol and 11-deoxycorticosterone/21-hydroxyprogesterone yielding cortisol or corticosterone, respectively (PubMed: 18215163).

Mechanistically, uses molecular oxygen inserting one oxygen atom into a substrate and reducing the second into a water molecule.

Two electrons are provided by NADPH via a two-protein mitochondrial transfer system comprising flavoprotein FDXR (adrenodoxin/ferredoxin reductase) and nonheme iron-sulfur protein FDX1 or FDX2 (adrenodoxin/ferredoxin) (PubMed: 18215163).