Numerical Classification of Some Rhodococci, Corynebacteria and Related Organisms

Abstract

Nineteen strains of Corynebacterium s.s., 23 received as C. equi or Rhodococcus equi, marker cultures of Arthrobacter, Brevibacterium, Bacterionema matruchotti, Cellulomonas flavigena, Kurthia zopfii, Listeria denitrificans, Microbacterium lacticum, R. rubropertinctus and 88 representatives of Mycobacterium, Nocardia, Rhodococcus and the ''aurantiaca'' taxon were the subject of numerical phenetic analyses using 92 characters. The data were examined using the simple matching (SSM) and Jaccard (SJ) coefficients and clustering was achieved using the average linkage algorithm. With a single exception, strains containing meso-diaminopimelic acid, arabinose, galactose and mycolic acids were recovered in 5 aggregate clusters corresponding to Corynebacterium s.s., Mycobacterium, Nocardia, Rhodococcus and the ''aurantiaca'' taxon. Most of the C. (Rhodococcus) equi strains formed a good taxospecies which included the type strain of C. hoagii. The numerical data and the results of earlier chemical and genetic studies also provide sufficient evidence for the transfer of B. matruchotii to Corynebacterium s.s. as C. matruchotii comb. nov. and for the recognition of R. globerulus sp. nov. for some strains previously classified as R. rubropertinctus (Hefferan) Goodfellow and Alderson. The classification of the remaining marker strains correlates well with other major developments in coryneform taxonomy.