Fatty acid characterization of rapidly growing pathogenic aerobic actinomycetes as a means of identification.

The fatty acid compositions of 39 type strains and 529 clinical or reference strains of pathogenic aerobic actinomycetes were analyzed after standardized culture by using the Microbial Identification System (MIS). Library entries for each type strain were created by using the MIS Library Generation Software, and the fatty acid profiles of clinical and reference strains were compared to these library entries. The bacteria separated into two large groups based upon major amounts of branched-chain or of saturated or monounsaturated straight-chain fatty acids. Identification of isolates was possible by using only the type strains for comparison, but fatty acid heterogeneity occurred within most species.