This study analyzed the fatty acid and mycolic acid composition of Bacterionema matruchotii and related organisms to clarify their taxonomic classification. Researchers examined five strains of B. matruchotii and compared them with Corynebacterium diphtheriae and C. xerosis using thin-layer chromatography, gas chromatography, and mass spectrometry. B. matruchotii strains contained short-chain mycolic acids (20-36 carbons) similar in structure and molecular weight to true corynebacteria, distinguishing them from nocardiae and mycobacteria which have larger mycolic acids. The long-chain fatty acids of B. matruchotii consisted mainly of straight-chain saturated and unsaturated components, matching the profile found in C. diphtheriae. These lipid compositions, combined with previous data on cell wall type, GC content, and fermentation characteristics, led the authors to recommend reclassifying Bacterionema from the family Actinomycetaceae to the Coryneform Group of Bacteria, reflecting its closer relationship to Corynebacterium species.

Key findings

• Bacterionema matruchotii contains mycolic acids with 20-36 carbons, structurally similar to Corynebacterium species but distinct from nocardiae and mycobacteria
• B. matruchotii fatty acid profiles consist primarily of straight-chain saturated and unsaturated acids, matching C. diphtheriae rather than other actinomycetes
• Mycolic acids were absent in other members of Actinomycetaceae family (Actinomyces, Arachnia, Bifidobacterium, Rothia), confirming Bacterionema's distinctiveness
• Combined lipid data with existing evidence on cell wall type, DNA composition, and fermentation products support taxonomic reclassification of Bacterionema to the Coryneform Group