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3-alpha-Hydroxysteroid Dehydrogenase (B-Specific) MeSH Descriptor Data 2025


MeSH Heading
3-alpha-Hydroxysteroid Dehydrogenase (B-Specific)
Tree Number(s)
D08.811.682.047.436.350.100
D08.811.682.047.820.186
Unique ID
D045002
RDF Unique Identifier
http://id.nlm.nih.gov/mesh/D045002
Scope Note
A 3-hydroxysteroid dehydrogenase which catalyzes the reversible reduction of the active androgen, DIHYDROTESTOSTERONE to 5 ALPHA-ANDROSTANE-3 ALPHA,17 BETA-DIOL. It also has activity towards other 3-alpha-hydroxysteroids and on 9-, 11- and 15- hydroxyprostaglandins. The enzyme is B-specific in reference to the orientation of reduced NAD or NADPH.
Entry Term(s)
3 alpha-Hydroxysteroid Dehydrogenase
3 alpha-Hydroxysteroid Dehydrogenase (B-Specific)
3 alpha-Hydroxysteroid Oxidoreductase
3alpha-Hydroxysteroid Dehydrogenase (B-specific)
5 alpha-3 alpha-Hydroxysteroid Dehydrogenase
5 alpha-Dihydroprogesterone 3 alpha-Hydroxysteroid Oxidoreductase
5-DP-3 alpha-HSO
NADPH-5 alpha-Dihydroprogesterone 3 alpha-Hydroxysteroid Oxidoreductase
Registry Numbers
EC 1.1.1.50
EC 1.1.1.50
Related Numbers
9028-56-2
EC 1.1.1.50
Previous Indexing
3-Hydroxysteroid Dehydrogenases (1979-2003)
Public MeSH Note
2004; 3-ALPHA-HYDROXYSTEROID DEHYDROGENASE (B-SPECIFIC) was indexed under 3-HYDROXYSTEROID DEHYDROGENASES 1979-2003; 5 ALPHA-DIHYDROPROGESTERONE 3 ALPHA-HYDROSTEROID OXIDOREDUCTASE was indexed under 3-HYDROXYSTEROID DEHYDROGENASES 1981-2003
History Note
2004; use 3-ALPHA-HYDROXYSTEROID DEHYDROGENASE (B-SPECIFIC) (NM) 1979-2003
Date Established
2004/01/01
Date of Entry
2003/07/09
Revision Date
2013/07/08
3-alpha-Hydroxysteroid Dehydrogenase (B-Specific) Preferred
5 alpha-Dihydroprogesterone 3 alpha-Hydroxysteroid Oxidoreductase Narrower
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