Purine nucleoside triphosphates in Streptomyces hydrogenans. Influence of steroids on the relative nucleotide level.

Various steroids in the culture medium of Streptomyces hydrogenans cause a rapid decrease of the relative GTP content of the cells. The relative ATP level is significantly diminished in the presence of progesterone and testosterone acetate. The initial decrease of the relative GTP content is proportional to the growth inhibitory effect of the steroids tested. There is no relationship between steroid-dependent induction of the synthesis of 20 beta- and 17 beta-hydroxysteroid dehydrogenase and the ability of the steroids to decrease the relative GTP content of the cells.