Characterization and solubilization of testosterone 17 beta-hydroxysteroid dehydrogenase in human hyperplastic...

17 beta-Hydroxysteroid dehydrogenase is a membrane-bound enzyme in human prostate. Solubilization of this enzyme can only be obtained in the presence of detergents. The optimal solubilization mixture contained 50 mM Tris-HCl buffer pH 9.0, 20% glycerol, 0.1 M KCl and 5 mg/ml of the non-ionic detergent N-octyl glucoside. In these conditions, the soluble fraction contained more than 90% of the enzymatic activity. A 2.5-fold increase of specific activity was obtained during solubilization under optimal conditions.