title: 3 beta, 17 beta-hydroxysteroid dehydrogenase of Pseudomonas testosteroni. Kinetic evidence for the bifunctional activity at a common catalytic site.
abstract: 3 beta, 17 beta-Hydroxysteroid dehydrogenase (3 beta 17 beta HSDH) is an NAD-dependent dehydrogenase which has a double specificity for the 3- and 17-positions on the steroid skeleton. When dehydroepiandrosterone (DHEA) is used as steroid substrate, and the assay coupled with ketosteroid-isomerase, the two reactions occur alternately and each reaction on the 3-position produces a chromophoric molecule. These two reactions can follow one another without dissociation of the coenzyme from the enzyme binding site. This is confirmed by competition experiments with another dehydrogenase.
authors.forename: P
authors.initials: P
authors.lastname: Minard
authors.forename: M D
authors.initials: MD
authors.lastname: Legoy
authors.forename: D
authors.initials: D
authors.lastname: Thomas
mesh_terms: D015067:17-Hydroxysteroid Dehydrogenases / Q000378:metabolism*; D000426:Alcohol Dehydrogenase; D000429:Alcohol Oxidoreductases / Q000378:metabolism; D000735:Androstenedione / Q000378:metabolism; D001667:Binding, Competitive; D002384:Catalysis; D003687:Dehydroepiandrosterone / Q000378:metabolism; D007700:Kinetics; D009243:NAD / Q000378:metabolism / Q000494:pharmacology; D011549:Pseudomonas / Q000201:enzymology*; D013251:Steroid Isomerases / Q000378:metabolism
chemical_list: D009243:NAD; D000735:Androstenedione; D003687:Dehydroepiandrosterone; D015067:17-Hydroxysteroid Dehydrogenases; D000429:Alcohol Oxidoreductases; D000426:Alcohol Dehydrogenase; C044256:3 (or 17)-beta-hydroxysteroid dehydrogenase; D013251:Steroid Isomerases; C022660:steroid delta-isomerase