Strains used in this study. NG: isolated after mutagenesis with N-methyl-N′-nitro-N-nitrosoguanidine.

Strains used in this study. NG: isolated after mutagenesis with N-methyl-N′-nitro-N-nitrosoguanidine.本研究所用菌株。NG菌株：经N-甲基-N'-硝基-N-亚硝基胍（N-methyl-N′-nitro-N-nitrosoguanidine）诱变处理后分离得到。