[Decomposition of cholesterol by Achromobacter candicans]

The decomposition of cholesterol by the cell suspensions of Achromobacter candicans 42 and by the cell-free extracts of this bacterium was studied. The decomposition of cholesterol in the presence of the wet biomass during four hours of the incubation was 72.5 percent, and with the cells that were preliminarily lyophilized or treated by acetone 49.8 and 23.0 percent, respectively. The activity decreased from 70.0 to 50.0 percent if the biomass was kept at minus 3 degrees C during 70 days. The decomposition of cholesterol by the cell-free preparations (supernatant and protein after precipitation with ammonium sulphate to 0.7 saturation) constituted 40.0 percent of the cholesterol contained in a sample. One of the intermediate products of cholesterol decomposition was delta4-cholesten-3-one.