[Cholesterol synthesis by several strains of Escherichia]

The results of the study of lipids in the media used for growing different Escherichia strains are presented. Donor plasma with carbon-labeled sodium acetate was used as culture medium. Those strains which induced an increase in cholesterol content in the medium after 48-hour incubation were considered cholesterin-synthetizing. During the growth of these strains the radioactive marker became incorporated into the lipids accumulated in the medium: phospholipids, cholesterol, fatty acids. The degree of this incorporation depended on the dose of labeled sodium acetate and the amount of the inoculated culture. Cholesterol-synthetizing activity of Escherichia is characteristic of only freshly isolated strains.