[The fatty acid composition of the cellular structures of Yersinia pestis]

Fatty acid composition of lipopolysaccharides (LPS) and cytoplasmic membranes (CPM) of Yersinia pestis [correction of the plaque microbe] has been studied. Concentration of certain acids in the LPS content proved sharply different and thus the strains were separated into groups. High content of 3-oxymiristinic acid was a distinction of vaccine strains. Virulent strains of one of the groups regularly differed from the rest of virulent strains by high content of laurinic acid. Laurinic and two nonidentified acids, which were not found in the virulent cultures, were present in CMP lipids of vaccine strains.