Oxidoreductases;
Acting on paired donors, with incorporation or reduction of molecular oxygen;
With reduced iron-sulfur protein as one donor, and incorporation of one atom of oxygen into the other donor
This cytochrome P-450 (heme-thiolate) enzyme, found in several bacterial pathogens, is involved in degradation of the host cholesterol. It catalyses the hydroxylation of the C-26 carbon, followed by oxidation of the alcohol to the carboxylic acid via the aldehyde intermediate, initiating the degradation of the alkyl side-chain of cholesterol. The products are exclusively in the (25R) conformation. The enzyme also accepts cholesterol as a substrate. cf. EC 1.14.15.29, cholest-4-en-3-one 26-monooxygenase [(25S)-3-oxocholest-4-en-26-oate forming]. The enzyme can receive electrons from ferredoxin reductase in vitro, its natural electron donor is not known yet.
History
EC 1.14.15.28 created 2016 as EC 1.14.13.221, transferred 2018 to EC 1.14.15.28
Driscoll MD, McLean KJ, Levy C, Mast N, Pikuleva IA, Lafite P, Rigby SE, Leys D, Munro AW
Title
Structural and biochemical characterization of Mycobacterium tuberculosis CYP142: evidence for multiple cholesterol 27-hydroxylase activities in a human pathogen.