[Transformation of steroids by actinobacteria: a review].

Development of pharmaceutical industry is currently aimed at introducing biotechnological processes on a large-scale and thereby replacing multiple-stage chemical syntheses. Actinobacteria are efficient biocatalysts of many processes involving steroid bioconversion, which hold considerable importance for the synthesis of hormonal drugs. The potential to catalyze the conversion of a broad spectrum of steroid substrates makes it possible to expect efficient utilization of these microorganisms in development of new technologies of manufacturing steroid pharmaceutical substances. The review is a first attempt to systematize data on the potential of actinobacteria to catalyze diverse reactions of steroid transformation (such as hydroxylation, introduction and reduction of double bonds, oxidation of steroid alcohols, reduction of ketones, side chain de-esterification and degradation, etc.), with emphasis on processes of practical biotechnological importance and progress in steroid bioconversion over the last ten years.