Steroid-protein interaction: Substrate specificity of 20.BETA.-hydroxysteroid dehydrogenase.

Properties of an antiserum against Streptomyces hydrogenans 20beta-hydroxysteroid dehydrogenase.

Antiserum against crystallized 20beta-hydroxysteroid dehydrogenase from Streptomyces hydrogenans was used for different immunodiffusion and immunoprecipitation tests to quantify the bacterial enzyme in cell-free supernatants of the microorganism. After immunoprecipitation and gel electrophoresis the molecular weight of the subunits of 20beta-hydroxysteroid dehydrogenase was calculated to be 27 ...

17 -Hydroxysteroid dehydrogenase of rat skin. Substrate specificity and inhibitors.

A 17fl-hydroxysteroid dehydrogenase activity has been demonstrated in the microsomal preparations made from the skin of newborn rats. The enzyme prefers NAD to NADP as the coenzyme and utilizes 17fi-estradiol as well as testosterone as substrates. The apparent K, values estimated for 17/?-estradiol are 4.1 X 10m6 M, for estrone 1.0 X 10d5 M, and for testosterone 4.0 X 10e6 M. The enzyme can be ...

Testicular steroid sulfatase. Substrate specificity and inhibition.

Kinetic studies of the cleavage of dehydroepiandrosterone-sulfate (i) and androstenediol-3-sulfate by a particulate enzyme preparation from a rat testicular microsomal fraction gave K m values of 2.04 x 10-6M for DHA-S and 0.935 x 10-6M for androstenediol-3-sulfate with identical Vma x values° Inhibition studies with equimolar concentrations of substrate and inhibitor demonstrated that 5~-andro...

Expression of Recombinant 3-Beta Hydroxysteroid Dehydrogenase Protein in E. coli

Conversion of mammalian 3alpha-hydroxysteroid dehydrogenase to 20alpha-hydroxysteroid dehydrogenase using loop chimeras: changing specificity from androgens to progestins.

Hydroxysteroid dehydrogenases (HSDs) regulate the occupancy and activation of steroid hormone receptors by converting potent steroid hormones into their cognate inactive metabolites. 3alpha-HSD catalyzes the inactivation of androgens in the prostate by converting 5alpha-dihydrotestosterone to 3alpha-androstanediol, where excess 5alpha-dihydrotestosterone is implicated in prostate disease. By co...