[Feasibility of obtaining a highly active mutant of Streptomyces hygroscopicus SU-A5 using induced mutagenesis]

Mutagenic and lethal effects of gamma-radiation, N-methyl-N'-nitro-N-nitrosoguanidine (MNNG) and 4-nitroquanidine-1-oxide were investigated on spore suspensions of Streptomyces hygroscopicus SU-A5. It was shown that all the agents induced high percentage of plus mutants. The most stable and active ones were induced by gamma-radiation. The frequency of the plus mutants and the variation coefficient were used as the criteria of the mutagen efficiency. The successive exposure to gamma-radiation, MNNG and gamma-radiation resulted in the formation of a mutant with the activity 3 times higher than that of the parent strain.