Binding of steroids by a partially purified periplasmic protein from Pseudomonas testosteroni.

Abstract

The androgen-binding periplasmic protein of Pseudomonas testosteroni was released by lysozyme-EDTA treatment of induced bacteria and partially purified by ammonium sulfate fractionation. The androgen-binding protein appeared in the 50–80% saturated fraction whereas steroid transforming enzymes and the estradiol-binding protein appeared in the 0-50% saturated fraction. The partial purification, however. did not alter the substrate specificity of the androgen-binding protein. Kinetics of binding at this stage of purification indicated a simple equilibrium binding process with independent binding sites.