7alpha-hydroxycholest-4-en-3-one 12alpha-hydroxylase

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In enzymology, a 7alpha-hydroxycholest-4-en-3-one 12alpha-hydroxylase (EC 1.14.13.95) is an enzyme that catalyzes the chemical reaction

7alpha-hydroxycholest-4-en-3-one + NADPH + H⁺ + O₂ $\rightleftharpoons$ 7alpha,12alpha-dihydroxycholest-4-en-3-one + NADP⁺ + H₂O

The 4 substrates of this enzyme are 7alpha-hydroxycholest-4-en-3-one, NADPH, H⁺, and O₂, whereas its 3 products are 7alpha,12alpha-dihydroxycholest-4-en-3-one, 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 7alpha-hydroxycholest-4-en-3-one,NADPH:oxygen oxidoreductase (12alpha-hydroxylating). Other names in common use include 7alpha-hydroxy-4-cholesten-3-one 12alpha-monooxygenase, CYP12, sterol 12alpha-hydroxylase (ambiguous), and HCO 12alpha-hydroxylase. This enzyme participates in ppar signaling pathway.

[edit] References

IUBMB entry for 1.14.13.95
BRENDA references for 1.14.13.95 (Recommended.)
PubMed references for 1.14.13.95
PubMed Central references for 1.14.13.95
Google Scholar references for 1.14.13.95
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Okuda KI, Bjorkhem I (1996). "Molecular cloning and expression of rabbit sterol 12alpha-hydroxylase". J. Biol. Chem. 271: 32269–75. doi:10.1074/jbc.271.50.32269. PMID 8943286.
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