Fatty acid composition of a Propionibacterium acnes vaccine and its relationship to immunostimulatory activity.

The distribution of lipids of Propionibacterium acnes (Corynebacterium parvum) vaccine strain in chloroform-methanol, ethanol and light petroleum extracts was determined. Firmly bound lipids released by hydrolysis were also investigated. The petroleum extract differs from other lipidic fractions in its fatty acid composition. The presence of linolic, tuberculostearic and 10-ketostearic acids and branched fatty alcohols was observed in addition to previously described fatty acids of P. acnes. Changes in fatty acid composition during growth of the vaccine strain were determined and extremes were found at 95 h of cultivation. These extremes coincided with a maximum in the immunostimulatory efficiency as measured by the spleen enlargement test. The biological activity of static and stirred cultures of the vaccine strain was in correlation with their fatty acid composition.