Chemical composition of variants of aerobic actinomycetes.

It has been shown previously that aerobic actinomycetes can be separated into four main groups on the basis of their cell wall composition. Six representatives of aerobic actinomycetes (Nocardia asteroides and Micropolyspora brevicatena, cell wall type IV; N. madurae, Microbispora rosea, cell wall type III; Actinoplanes sp., cell wall type II; Streptomyces griseus, cell wall type I) were subjected to selecting agents which permitted the isolation of stable variants morphologically different from the parent strain. Whole cell analyses of 134 substrains from the six parents revealed no significant change in the isomeric form of diaminopimelic acid or in sugar constituents. Analyses of cell wall preparations from 52 of these did not reveal any change in the diagnostic constituents of their murein or polysaccharides.