title: The stereospecificity of 3 alpha- and 12 alpha-bile salt hydroxysteroid dehydrogenase systems from four microbial sources.
abstract: 5 beta-Cholanoates, having a hydroxyl group in the 3 alpha and 3 beta and/or 12 alpha and 12 beta configurations, were tested as substrates for two preparation of 3 alpha-hydroxysteroid dehydrogenase (HSDH) and two preparations of 12 alpha-HSDH. When the 3-OH group was in the alpha configuration, both 3 alpha-HSDH preparations reacted, but when it was in the beta configuration, neither 3 alpha-HSDH preparations reacted. This also held true for the 12 alpha-HSDH preparations.
mesh_terms: D015096:3-Hydroxysteroid Dehydrogenases / Q000378:metabolism*; D045002:3-alpha-Hydroxysteroid Dehydrogenase (B-Specific); D001647:Bile Acids and Salts / Q000378:metabolism*; D003013:Clostridium / Q000201:enzymology*; D005051:Eubacterium / Q000201:enzymology*; D006913:Hydroxysteroid Dehydrogenases / Q000378:metabolism*; D011549:Pseudomonas / Q000201:enzymology*; D013237:Stereoisomerism; D013379:Substrate Specificity
chemical_list: D001647:Bile Acids and Salts; D015096:3-Hydroxysteroid Dehydrogenases; D006913:Hydroxysteroid Dehydrogenases; C019189:12 alpha-hydroxysteroid dehydrogenase; D045002:3-alpha-Hydroxysteroid Dehydrogenase (B-Specific)