Reaction: cholesterol + reduced adrenal ferredoxin + O2 = pregnenolone + 4-methylpentanal + oxidized adrenal ferredoxin + H2O
Other name(s): cholesterol desmolase; cytochrome P-450scc; desmolase, steroid 20-22; C27-side chain cleavage enzyme; cholesterol 20-22-desmolase; cholesterol C20-22 desmolase; cholesterol side-chain cleavage enzyme; cholesterol side-chain-cleaving enzyme; enzymes, cholesterol side-chain-cleaving; steroid 20-22 desmolase; steroid 20-22-lyase
Systematic name: cholesterol,reduced-adrenal-ferredoxin:oxygen oxidoreductase (side-chain-cleaving)
Comments: A heme-thiolate protein. The reaction proceeds in three stages, with hydroxylation at C-20 and C-22 preceding scission of the side-chain at C-20.
Links to other databases: BRENDA, EXPASY, KEGG, PDB, CAS registry number: 37292-81-2, 440354-98-3
References:
1. Hanukoglu, I. and Jefcoate, C.R. Mitochondrial cytochrome P-450sec. Mechanism of electron transport by adrenodoxin. J. Biol. Chem. 255 (1980) 3057-3061. [PMID: 6766943]
2. Hanukoglu, I., Spitsberg, V., Bumpus, J.A., Dus, K.M. and Jefcoate, C.R. Adrenal mitochondrial cytochrome P-450scc. Cholesterol and adrenodoxin interactions at equilibrium and during turnover. J. Biol. Chem. 256 (1981) 4321-4328. [PMID: 7217084]