7alpha-hydroxysteroid dehydrogenase

7-alpha-hydroxysteroid dehydrogenase
Identifiers
EC no.	1.1.1.159
CAS no.	39361-64-3
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
Search PMC articles PubMed articles NCBI proteins

In enzymology, a 7alpha-hydroxysteroid dehydrogenase (EC 1.1.1.159) is an enzyme that catalyzes the chemical reaction

3alpha,7alpha,12alpha-trihydroxy-5beta-cholanate + NAD⁺${\displaystyle \rightleftharpoons }$ 3alpha,12alpha-dihydroxy-7-oxo-5beta-cholanate + NADH + H⁺

Thus, the two substrates of this enzyme are 3alpha,7alpha,12alpha-trihydroxy-5beta-cholanate and NAD⁺, whereas its 3 products are 3alpha,12alpha-dihydroxy-7-oxo-5beta-cholanate, NADH, 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 7alpha-hydroxysteroid:NAD⁺ 7-oxidoreductase. Other names in common use include 7alpha-hydroxy steroid dehydrogenase, and 7alpha-HSDH.

Structural studies

As of late 2007, 3 structures have been solved for this class of enzymes, with PDB accession codes 1AHH, 1AHI, and 1FMC.

References

• Haslewood ES, Haslewood GA (July 1976). "The specificity of a 7 alpha-hydroxy steroid dehydrogenase from Escherichia coli". The Biochemical Journal. 157 (1): 207–10. doi:10.1042/bj1570207. PMC   1163832 . PMID   786279.
• MacDonald IA, Roach PD (August 1981). "Bile induction of 7 alpha- and 7 beta-hydroxysteroid dehydrogenases in Clostridium absonum". Biochimica et Biophysica Acta. 665 (2): 262–9. doi:10.1016/0005-2760(81)90011-4. PMID   6945134.
• Macdonald IA, Williams CN, Mahony DE (June 1973). "7Alpha-hydroxysteroid dehydrogenase from Escherichia coli B: preliminary studies". Biochimica et Biophysica Acta (BBA) - Enzymology. 309 (2): 243–53. doi:10.1016/0005-2744(73)90022-3. PMID   4581498.
• Macdonald IA, Williams CN, Mahony DE, Christie WM (March 1975). "NAD- and NADP-dependent 7alpha-hydroxysteroid dehydrogenases from bacteroides fragilis". Biochimica et Biophysica Acta (BBA) - Enzymology. 384 (1): 12–24. doi:10.1016/0005-2744(75)90091-1. PMID   236764.