Microbiological Agencies in the Degradation of Steroids

Abstract

From an examination of 230 soil samples, cholesterol-breakdown in soils has been shown to result from the activities of spp. of Proadinomyces, and in particular of P. erythropolis. Other bacteria, moulds and actinomycetes are inactive in this respect. Two new spp. of Proactinomyces, P. aquosus and P. restrictus, are descr. A survey of the distr. of Proactinomyces spp. in soils indicated their relative abundance in fertile areas; under conditions of waterlogging, extreme acidity, and lack of aeration, they were present only infrequently. In the presence of CaCO3 to prevent acid accumulation, the average decompn. of cholesterol in mineral-salt soln. by Proactinomyces spp. during 2 months'' incubation at 25[degree] was approx. 30%.