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Cholesterol Side-Chain Cleavage Enzyme MeSH Descriptor Data 2025


MeSH Heading
Cholesterol Side-Chain Cleavage Enzyme
Tree Number(s)
D08.244.453.484.250
D08.244.453.915.212
D08.811.682.690.708.170.425.250
D08.811.682.690.708.170.915.212
D12.776.422.220.453.484.250
D12.776.422.220.453.915.212
Unique ID
D002786
RDF Unique Identifier
http://id.nlm.nih.gov/mesh/D002786
Scope Note
A mitochondrial cytochrome P450 enzyme that catalyzes the side-chain cleavage of C27 cholesterol to C21 pregnenolone in the presence of molecular oxygen and NADPH-FERRIHEMOPROTEIN REDUCTASE. This enzyme, encoded by CYP11A1 gene, catalyzes the breakage between C20 and C22 which is the initial and rate-limiting step in the biosynthesis of various gonadal and adrenal steroid hormones.
Entry Term(s)
20,22-Desmolase
CYP 11A1
CYP11A1
Cholesterol Desmolase
Cholesterol Monooxygenase (Side-Chain-Cleaving)
Cytochrome P-450 CYP11A1
Cytochrome P-450(scc)
Cytochrome P450 11A1
Cytochrome P450scc
Registry Numbers
EC 1.14.15.6
CAS Type 1 Name
Cholesterol,reduced-adrenal-ferredoxin:oxygen oxidoreductase (side-chain-cleaving)
Previous Indexing
Cholesterol (1971-1974)
Multienzyme Complexes (1973-1974)
Oxidoreductases (1971-1974)
Public MeSH Note
2003; see CHOLESTEROL MONOOXYGENASE 1997-2002, see CHOLESTEROL DESMOLASE 1988-1996, see OXIDOREDUCTASES 1975-1987
History Note
2003 (1975)
Date Established
1988/01/01
Date of Entry
1974/11/19
Revision Date
2016/05/27
Cholesterol Side-Chain Cleavage Enzyme Preferred
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