Study on mutagenesis and breeding of GA4+7 producing strain
The GA4+7-producing strain was used to prepare mycelium suspension and protoplast suspension,and the iterative mutagenesis was carried out by ultraviolet irradiation and lithium chloride mutagenesis.The mutagenesis-treated bacterial solution was coated on a plate,and the single colonies on the plate were screened by shaking bottle culture.Finally,strain GX34-4 was obtained.Compared to the starting strain GA4+7,the titer of GX34-4 in the shake flask was increased by about 25％,and the titer in the 50 L fermenter was increased by about 40％.The appearance and titer of the starting strain were unstable.The genetic stability of mutant GX34-4 was good,and the yield of mutant GX34-4 was not significantly reduced after five successive generations.which was also stable in a 50 L fermenter.
NETL
NSTL
万方数据
