A mutant of a scotochromogenic Mycobacterium detected by colony morphology and lipid studies.

Fregnan, G. B. (University of Wisconsin, Madison), D. W. Smith, and H. M. Randall. A mutant of a scotochromogenic Mycobacterium detected by colony morphology and lipid studies. J. Bacteriol. 83:828-836. 1962.-A variant of a scotochromogenic strain of Mycobacterium is described. This mutant was recognized by studies of colony morphology and lipid content. Mycoside D was shown to be present in the smooth-Sy variety but absent in the rough-Ry variety. The rough-Ry variety appeared spontaneously from smooth-Sy, or by induction after prolonged incubation in a synthetic liquid medium or exposure to ultraviolet irradiation. This mutation is not reversible.