Binding of steroids by microorganisms.

Hartman, Ronald E. (American Cyanamid Co., Pearl River, N.Y.) and Chester E. Holmlund. Binding of steroids by microorganisms. J. Bacteriol. 84:1254-1259. 1962.-Certain microorganisms, particularly higher fungi, are able to bind steroids. The steroids can be recovered by solvent extraction only after lyophilization of the cultures. There appears to be a relationship between steroid structure and avidity for the microbial-binding component from Penicillium canescens. Sterols which possess a long side chain and a 3beta-hydroxy-5-ene group are particularly susceptible to microbial binding. The sterol-binding component of P. canescens is released by rupture of the cells. After liberation from the intact cells, it appears to be highly unstable in the presence of other cellular constituents.