Isolation of a hydroxyproline-secreting pigment-deficient mutant of Nostoc sp. by metronidazole selection

Abstract

A pigment-deficient mutant of Nostoc sp. was induced by N-methyl-N′-nitro-N-nitrosoguanidine and selected in a medium containing metronidazole. It formed chains of heterocysts, grew more slowly than the control, and excreted hydroxyproline into the medium, imparting a pinkish-brown colour to the cultures. © 1985 Oxford University Press.