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Steroid 12-alpha-Hydroxylase MeSH Descriptor Data 2026


MeSH Heading
Steroid 12-alpha-Hydroxylase
Tree Number(s)
D08.244.453.900.500
D08.244.453.915.730
D08.811.682.690.708.170.900.500
D08.811.682.690.708.170.915.730
D12.776.422.220.453.900.500
D12.776.422.220.453.915.730
Unique ID
D013253
RDF Unique Identifier
http://id.nlm.nih.gov/mesh/D013253
Scope Note
A liver microsomal cytochrome P450 enzyme that catalyzes the 12-alpha-hydroxylation of a broad spectrum of sterols in the presence of molecular oxygen and NADPH-FERRIHEMOPROTEIN REDUCTASE. This enzyme, encoded by CYP8B1gene, converts 7-alpha-hydroxy-4-cholesten-3-one to 7-alpha-12-alpha-dihydroxy-4-cholesten-3-one and is required in the synthesis of BILE ACIDS from cholesterol.
Entry Term(s)
12-alpha-Hydroxylase
12alpha-Hydroxylase
CYP8B1
Cytochrome P450 8B1
Cytochrome P450 CYP8B1
Steroid 12-Hydroxylase
Steroid 12-Monooxygenase
Steroid-12-Hydroxylase
Steroid-12-Monooxygenase
Sterol 12 alpha-Hydroxylase
Sterol 12-alpha-Hydroxylase
Registry Numbers
EC 1.14.18.8
CAS Type 1 Name
Steroid, hydrogen-donor:oxygen oxidoreductase (12-alpha-hydroxylating)
Previous Indexing
Steroid Hydroxylases (1973-1977)
Public MeSH Note
2003; see STEROID 12-MONOOXYGENASE 1997-2002, see STEROID 12-HYDROXYLASE 1991-1996, see STEROID HYDROXYLASES 1978-1990; for STEROID 12-MONOOXYGENASE see STEROID 12-HYDROXYLASE 1978-1996
History Note
2003 (1978)
Date Introduced
1991/01/01
Last Updated
2016/06/28
Steroid 12-alpha-Hydroxylase Preferred
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