IUBMB Enzyme Nomenclature


Accepted name: 3α(or 20β)-hydroxysteroid dehydrogenase

Reaction: androstan-3α,17β-diol + NAD+ = 17β-hydroxyandrostan-3-one + NADH + H+

Other name(s): cortisone reductase; (R)-20-hydroxysteroid dehydrogenase; 20β-hydroxy steroid dehydrogenase; Δ4-3-ketosteroid hydrogenase; 20β-hydroxysteroid dehydrogenase; 3α,20β-hydroxysteroid:NAD+-oxidoreductase; NADH-20β-hydroxysteroid dehydrogenase; 20β-HSD

Systematic name: 3α(or 20β)-hydroxysteroid:NAD+ oxidoreductase

Comments: The 3α-hydroxy group or 20β-hydroxy group of pregnane and androstane steroids can act as donor.

Links to other databases: BRENDA, EXPASY, KEGG, Metacyc, PDB, CAS registry number: 9028-42-6


1. Edwards, C.A.F. and Orr, J.C. Comparison of the 3α-and 20β-hydroxysteroid dehydrogenase activities of the cortisone reductase of Streptomyces hydrogenans. Biochemistry 17 (1978) 4370-4376. [PMID: 718844]

2. Hübener, H.J. and Sahrholz, F.G. 20β-hydroxy-steroid-dehydrogenase. II. Darstellung und Kristallisation. Biochem. Z. 333 (1960) 95-105.

3. Hübener, H.J., Sahrholz, F.G., Schmidt-Thomé, J., Nesemann, G. and Junk, R. 20β-Hydroxy-Steroid-Dehydrogenase, ein neues kristallines Enzym. Biochim. Biophys. Acta 35 (1959) 270-272.

4. Lynn, W.S. and Brown, R.H. The conversion of progesterone to androgens by testes. J. Biol. Chem. 232 (1958) 1015-1030.

5. Strickler, R.C., Covey, D.F. and Tobias, B. Study of 3α, 20 β-hydroxysteroid dehydrogenase with an enzyme-generated affinity alkylator: dual enzyme activity at a single active site. Biochemistry 19 (1980) 4950-4954. [PMID: 6936053]

6. Sweet, F. and Samant, B.S. Bifunctional enzyme activity at the same active site: study of 3α and 20β activity by affinity alkylation of 3α, 20β-hydroxysteroid dehydrogenase with 17-(bromoacetoxy)steroids. Biochemistry 19 (1980) 978-986. [PMID: 6928375]

[EC created 1961, modified 1986]

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