Studies On The Mutant Breeding Of L-Arginine-Produing Strain

The Experiment in this paper was to study the mutant breeding of L-arginine- producing strain .NTG mutagenesis selective breeding: The strain 414 produces acid 0.12mg/ml, the structure synonym SG resistant density is 0.4mg/ml,for embarks the strain, after NTG chemistry mutagenesis, use the SG of 0.6 -1.0mg/ml density to take density screening as initially sieves.Then duplicate sieves obtains produces the acid distinct enhancement and the stable strain 610 ,produces acid 0.24mg/ml, the structure synonym SG resistant density is 0.8mg/ml.NTG, N~+ pour into the mutafacient selective breeding:the NTG mutagenesis to the strain 610, use the SG 1.0 -1.4mg/ml density to take resistance screening as initially sieves.Then duplicate sieves has not obtained produces the acid distinct enhancement the strain; The mutagenesis of N~+ pouring into the strain 610, use the SG of 1.0-1.2mg/ml, the L-HA of 5.0-15mg/ ml combination density to take the screening density as nitially sieves .The duplicate sieves obtains one to produce the acid distinct enhancement and the stable strain 1603 .produces acid 0.32mg/ml, the structure synonym SG resistant density is 1.0mg/ml, L-HA is 15.0mg/ml.Ultraviolet ray, NTG mutagenesis selective breeding: The ultraviolet ray mutagenesis to the strain 1603,use the SG of 1.0-1.4mg/ml, the L-HA of 15.0mg/ml,the M-cys of 10.0-15.0mg/ml combination density to take resistance screening as initially sieves.Then duplicate sieves has not obtained produces the acid distinct enhancement the strain; The NTG mutagenesis to the strainl603, use the SG of 1.0-1.4mg/ml, the L-HA of 15.0mg/ml,the M-cys of 10.0-15.0mg/ml combination density to take resistance screening as initially sieves.Then duplicate sieves obtains one to produce the acid distinct enhancement and stable strain G8 ,produces...