[Application of microbial enzymes in studies of steroid metabolism (author's transl)].

In vitro models are necessary for studying the biotransformation of new steroid drugs and to determine the structure of the metabolites and their biological activity. For that reason microorganisms and their enzymes were used to investigate the anabolic steroid Oral-Turinabol (4-chloro-17alpha-methyl-17beta-hydroxy-1,4-androstadiene-3-one). Clostridium paraputrificum transformed Oral-Turinabol into the hydrogenation products 4beta-chloro-17alpha-methyl-17beta-hydroxy-5beta-1-androstene-3-one (I) and 4beta-chloro-17alpha-methyl-5beta-1-androstene-3alpha,17beta-biol (II); Rhodotorula glutinis to 4alpha-chloro-17alpha-methyl-5alpha-1-androstene-3beta,17beta-hydroxy-5alpha-1-androstene-3-one (III) and 4alpha-chloro-17alpha-methyl-5alpha-1-androstene-3beta,17beta-diol (IV). The hydroxylation products 6beta-hydroxy- (V), 7beta-hydroxy- (VI), 15alpha- (VII) and 15beta-hydroxy-Oral-Turinabol (VIII) resulted from Absidia glauca and Aspergillus flavus. The metabolites II-V were isolated until now from mammals.