3alpha-hydroxysteroid dehydrogenase (B-specific)

In enzymology, a 3alpha-hydroxysteroid dehydrogenase (B-specific) (EC 1.1.1.50) is an enzyme that catalyzes the chemical reaction

androsterone + NAD(P)⁺ ${\displaystyle \rightleftharpoons }$ 5alpha-androstane-3,17-dione + NAD(P)H + H⁺

The 3 substrates of this enzyme are androsterone, NAD⁺, and NADP⁺, whereas its 4 products are 5alpha-androstane-3,17-dione, NADH, 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, more specifically it is part of the group of hydroxysteroid dehydrogenases. The systematic name of this enzyme class is 3alpha-hydroxysteroid:NAD(P)⁺ oxidoreductase (B-specific). Other names in common use include hydroxyprostaglandin dehydrogenase, 3alpha-hydroxysteroid oxidoreductase, and sterognost 3alpha. This enzyme participates in 3 metabolic pathways: bile acid biosynthesis, c21-steroid hormone metabolism, and androgen and estrogen metabolism.

Structural studies

As of late 2007, 7 structures have been solved for this class of enzymes, with PDB accession codes 1AFS, 1FJH, 1FK8, 1LWI, 1RAL, 2DKN, and 2FVL.

References

• Jarabak J, Talalay P (1960). "Stereospecificity of hydrogen transfer by pyridine nucleotide-linked hydroxysteroid dehydrogenases". J. Biol. Chem. 235: 2147–51. PMID 14406805.
• Kochakian CD, Carroll BR, UHRI B (1957). "Comparisons of the oxidation of C19-hydroxysteroids by guinea pig liver homogenates". J. Biol. Chem. 224 (2): 811–8. PMID 13405910.
• Marcus PI; Talalay P (1956). "Induction and purification of alpha- and beta-hydroxysteroid dehydrogenases". J. Biol. Chem. 218 (2): 661–674. PMID 13295221.
• Penning TM, Sharp RB (1987). "Prostaglandin dehydrogenase activity of purified rat liver 3 alpha-hydroxysteroid dehydrogenase". Biochem. Biophys. Res. Commun. 148 (2): 646–52. doi:10.1016/0006-291X(87)90925-9. PMID 3479982.

This page was last edited on 4 January 2024, at 13:07