Numerical classification of some Rhodococci, Corynebacteria and related organisms

Abstract

Nineteen strains of Corynebacterium sensu stricto, 23 received as Corynebacterium equi or Rhodococcus equi, marker cultures of Arthrobacter, Brevibacterium, Bacterionema matruchotii, Cellulomonas flavigena, Kurthia zopfii, Listeria denitrificans, Microbacterium lacticum, Rhodococcus 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 five aggregate clusters corresponding to Corynebacterium sensu stricto, Mycobacterium, Nocardia, Rhodococcus and the 'aurantiaca' taxon. Most of the Corynebacterium (Rhodococcus) equi strains formed a good taxospecies which included the type strain of Corynebacterium hoagii. The numerical data, and the results of earlier chemical and genetical studies, also provide sufficient evidence for the transfer of Bacterionema matruchotii to Corynebacterium sensu stricto as Corynebacterium matruchotii comb.nov. and for the recognition of Rhodococcus globerulus sp.nov. for some strains previously classified as Rhodococcus rubropertinctus (Hefferan) Goodfellow & Alderson. The classification of the remaining marker strains correlates well with other major developments in coryneform taxonomy.