Effects of 60Co γ-rays irradiation on saccharopolyspora erythraes M

Spores of Saccharopolyspora erythraea M with different protective agents were treated with different doses of ∼ 60 Co γ-rays irradiation, and their morphological variations were observed and mutants were selected. The results indicated that 20% glycerol (contain 0.1% tween-20) showed a better protective effect to irradiation, and lethal ratio reached 90% when irradiation dose at 400 Gy, therefore 400 Gy was selected as the appropriate dose. 1203 strains were obtained by streptomycin resistance screening, among them, 5 strains changed in their phenotype and 2 strain fermentation products had antibacterial activity. The morphological variation rate was 0.4% and positive mutation rate was 0.167%. (authors)