Further evidence for the phylogenetic coherence of actinomycetes with Group B-peptidoglycan and evidence for the phylogenetic intermixing of the generaMicrobacteriumandAureobacteriumas determined by 16S rDNA analysis

A 16S rDNA study was performed on at least two species, including the type strain of the type species, of each genus described to possess peptidoglycan of Group B. Analyses confirm that these actinomycetes form a phylogenetically coherent cluster within the arthrobacteria subline of descent. While members of the genera Agromyces, Clavibacter, Curtobacterium and Rathayibacter appear to be phylogenetically coherent, members of Microbacterium and Aureobacterium do not cluster according to their taxonomic affiliation but form one large cluster in which species of both genera are intermixed. Species with no taxonomic standing, i.e. “Corynebacterium aquaticum”, and “Brevibacterium helvolum” form three separate sublines of descent and can be considered nuclei of future novel genera.