Relationships Among Streptomycetes, Nocardiae, Mycobacteria and Other Actinomycetes

SUMMARYSome physiological reactions of 63 strains of actinomycetes, including 8 designated as Mycobacterium, 29 as Nocardia, 18 as Streptomyces, 4 as Jensenia, 2 as Micromonospora, 1 as Actinoplanes and 1 as Streptosporangium were studied. Based on overall similarity the microbes were arranged into a branching continuum in which the verticillate streptomycetes were together, as were the streptomycetes with spiral spore-chains and those with straight spore-chains. The nocardiae with persistent mycelial stages were intermediate between the streptomycetes and the mycobacteria. Cultures such as Jensenia canicruria, Mycobacterium rhodochrous and Nocardia corallina were placed as a branch originating from typical nocardiae. Susceptibility of 8 nocardiae and 4 mycobacteria to actinophage was also determined. Phage typing results indicate that the N. corallina group is more closely allied to N. asteroides and N. brasiliensis than to M. smegmatis and M. friburgensis.