Long chain fatty acids of peptococci and peptostreptococci

The long-chain fatty acids extracted from the whole cells of 12 clinically significant species of peptococci and peptostreptococci were characterized by gas liquid chromatography. The resulting methylated fatty acid profiles (and some unidentified compounds) of 82 strains allowed the 12 species to be separated into four groups. Fifteen strains of Peptostreptococcus anaerobius were placed in group 1 because they had a unique, prominent compound that occurred in the area where a C₈ to C₁0 fatty acid would be expected. Group 11, consisting of Peptostreptococcus intermedius, Peptostreptococcus micros, Peptostreptococcus parvulus, Peptococcus morbillorum, and Peptococcus constellatus, produced C₁4, C(16:1), C(18:1), and C₁₈ fatty acids. Peptococcus prevotii, Peptococcus variabilus, Peptococcus magnus, Peptococcus asaccharolyticus, and Peptostreptococcus productus were placed in group 111 because they contained three to six additional, unidentified compounds that strikingly differentiated them from group 11. Peptococcus saccharolyticus was the single species assigned to group 1V because it yielded C₁₄, C₁₆, C(18:1), and C₂₀ fatty acids and a prominent unidentified peak that occurred between C₁₄ and C₁₆ fatty acids. This study indicated that cellular long-chain fatty acids may be an important tool in clarifying the taxonomy of the peptococci and peptostreptococci.