title: Characterization of bovine liver cytosolic 3 alpha-hydroxysteroid dehydrogenase and its aldo-keto reductase activity.
abstract: 1. 3 alpha-Hydroxysteroid dehydrogenase was purified to homogeneity from bovine cytosolic fraction, which was monomeric and its molecular weight was estimated to be about 35 kDa. 2. The enzyme had ability to catalyze NADP(H)-dependent oxidoreduction of position 3 alpha-hydroxy and keto group of steroids and also could catalyze the reduction of some ketones and quinones. 3. In addition, benzenedihydrodiol was one of the substrates of dehydrogenase activity with NADP+. 4. Indomethacin, synthetic steroids and SH-reagents were potent inhibitors for this enzyme. 5. Inactivation of the enzyme by GSSG-treatment was restored to its original activity by the addition of DTT. 6. The presence of coenzyme, 0.33 mM NADP+, completely protected from the DTNB-inactivation. 7. Bovine liver cytosolic enzyme immunologically crossreacted with rat liver 3 alpha-hydroxysteroid dehydrogenase.
authors.affiliation: Laboratory of Biochemistry, Faculty of Pharmaceutical Sciences, Osaka University, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Nanjo
authors.forename: T
authors.initials: T
authors.lastname: Terada
authors.forename: T
authors.initials: T
authors.lastname: Umemura
authors.forename: T
authors.initials: T
authors.lastname: Nishinaka
authors.forename: T
authors.initials: T
authors.lastname: Mizoguchi
authors.forename: T
authors.initials: T
authors.lastname: Nishihara
mesh_terms: D015096:3-Hydroxysteroid Dehydrogenases / Q000037:antagonists & inhibitors / Q000276:immunology / Q000378:metabolism*; D000429:Alcohol Oxidoreductases / Q000378:metabolism*; D000449:Aldehyde Reductase; D000074408:Aldo-Keto Reductases; D000818:Animals; D015153:Blotting, Western; D002417:Cattle; D003429:Cross Reactions; D003600:Cytosol / Q000201:enzymology*; D004220:Disulfides / Q000494:pharmacology; D004591:Electrophoresis, Polyacrylamide Gel; D008099:Liver / Q000201:enzymology*; D051381:Rats; D013379:Substrate Specificity; D013439:Sulfhydryl Reagents / Q000494:pharmacology
chemical_list: D004220:Disulfides; D013439:Sulfhydryl Reagents; D015096:3-Hydroxysteroid Dehydrogenases; D000429:Alcohol Oxidoreductases; D000074408:Aldo-Keto Reductases; D000449:Aldehyde Reductase