12alpha-hydroxysteroid dehydrogenase
In enzymology, a 12alpha-hydroxysteroid dehydrogenase (EC 1.1.1.176) is an enzyme that catalyzes the chemical reaction
- 3alpha,7alpha,12alpha-trihydroxy-5beta-cholanate + NADP+ 3alpha,7alpha-dihydroxy-12-oxo-5beta-cholanate + NADPH + H+
12-alpha-hydroxysteroid dehydrogenase | |||||||||
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Identifiers | |||||||||
EC no. | 1.1.1.176 | ||||||||
CAS no. | 61642-40-8 | ||||||||
Databases | |||||||||
IntEnz | IntEnz view | ||||||||
BRENDA | BRENDA entry | ||||||||
ExPASy | NiceZyme view | ||||||||
KEGG | KEGG entry | ||||||||
MetaCyc | metabolic pathway | ||||||||
PRIAM | profile | ||||||||
PDB structures | RCSB PDB PDBe PDBsum | ||||||||
Gene Ontology | AmiGO / QuickGO | ||||||||
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Thus, the two substrates of this enzyme are 3alpha,7alpha,12alpha-trihydroxy-5beta-cholanate and NADP+, whereas its 3 products are 3alpha,7alpha-dihydroxy-12-oxo-5beta-cholanate, NADPH, and H+.
This enzyme belongs to the family of oxidoreductases, specifically those acting on the CH-OH group of donor with NAD+ or NADP+ as acceptor. The systematic name of this enzyme class is 12alpha-hydroxysteroid:NADP+ 12-oxidoreductase. Other names in common use include 12alpha-hydroxy steroid dehydrogenase, 12alpha-hydroxy steroid dehydrogenase, NAD+-dependent 12alpha-hydroxysteroid dehydrogenase, and NADP+-12alpha-hydroxysteroid dehydrogenase. This enzyme is involved in a metabolic pathway that degrades bile acids into cholesterol.
References
- MacDonald IA, Mahony DE, Jellet JF, Meier CE (1977). "NAD-dependent 3alpha- and 12alpha-hydroxysteroid dehydrogenase activities from Eubacterium lentum ATCC no. 25559". Biochim. Biophys. Acta. 489 (3): 466–76. doi:10.1016/0005-2760(77)90167-9. PMID 201289.
- Mahony DE, Meier CE, Macdonald IA, Holdeman LV (1977). "Bile salt degradation by nonfermentative clostridia". Appl. Environ. Microbiol. 34 (4): 419–23. PMC 242673. PMID 921266.