An Asporogenous Variant of Streptomyces griseus

Summary: A non-sporulating form of Streptomyces griseus occurred spontaneously in culture. It appears to be a true variant of the species. Ultra-violet irradiation stimulated the variation. The variant was readily isolated on media containing relatively large amounts of organic nitrogen, but capable of propagation upon very simple media. The fact that the variant can be stabilized throws some doubt upon the validity of the present basis for classification of the actinomycetes.