CELLULAR FATTY-ACID COMPOSITION, SOLUBLE-PROTEIN PROFILE, AND ANTIMICROBIAL RESISTANCE PATTERN OF EUBACTERIUM-LENTUM

Phenotypic heterogeneity among isolates of Eubacterium lentum has been recognized for many years, To better delineate their taxonomic relate dness, 29 clinical isolates of E. lentum were examined for soluble-pro tein content, cellular fatty acid profile, and antimicrobial resistanc e pattern in order to ascertain whether differences in these character istics could be correlated with differences in biochemical activities. Among 29 isolates we could identify 6 that were different from all th e others. These strains were coccobacilli with translucent colonies; t hey were catalase and H2S negative, not fluorescent under UV light, an d susceptible to beta-lactam drugs; growth was not stimulated by argin ine; and fatty acid analysis revealed the presence of straight-chain f atty acids. The remainder of the strains, including the type species, were pleomorphic bacilli with speckled colonies and were catalase and H2S positive; all but two were fluorescent under UV light; they were r esistant to beta-lactam antibiotics; growth was greatly stimulated by arginine; and they demonstrated saturated branched-chain fatty acids. Our data suggest that E. lentum can be further differentiated into dif ferent types.