The Cell Wall Composition and Distribution of Free Mycolic Acids in Named Strains of Coryneform Bacteria and in Isolates from Various Natural Sources

The major cell wall amino acids and sugars in 177 strains of coryneform bacteria were determined using a ‘rapid’method. Representatives were examined for free mycolic acids and the oxygen requirements of all strains were determined. Included were named strains, most of which were labelled Arthrobacter, Brevibacterium, Cellulomonas, Corynebacterium or Microbacterium , and a similar number of unnamed isolates from various natural sources. Strains which contained meso ‐diaminopimelic acid (DAP) were divided into four groups according to their oxygen requirements, the wall sugars and the occurrence and nature of free mycolic acids. Group 1 strains were mainly facultatively anaerobic and contained arabinose and mycolic acids of the Corynebacterium type. They were considered to be members of Corynebacterium sensu stricto and included Cor. diphtheriae and related animal parasites, Microbact. flavum , and Cor. glutamicum and similar species. Group 2 strains were aerobic, contained arabinose and mycolic acids of the ‘rhodochrous’type and were considered members of the ‘ rhodochrous ’complex. Group 3 strains were aerobic, contained ribose and no mycolic acids. Most were Br. linens strains from cheese but a few, possibly related strains, were from other habitats. Group 4 strains were aerobic and contained neither a pentose sugar nor mycolic acids and were of unknown taxonomic status. Most remaining strains contained lysine or ornithine in the wall and smaller numbers contained L‐DAP or diaminobutyric acid; none contained mycolic acids. The chemotaxonomic data are discussed in relation to recent numerical taxonomic studies of coryneform bacteria.