【摘要】 结合“神舟四号”无人飞船的试验条件和具体搭载要求 ,对转谷氨酰胺酶生产菌株Streptomycessp .WZFF .L -M 1(酶活 1.74U/mL)的孢子和菌丝体以 1 甲基 3硝基 1 亚硝基胍 (NTG)分别进行多种地面模拟比较性的诱变育种试验 ,发现诱变处理后菌落的形态变异等特征与产酶能力相关 ,经初筛和复筛的菌种驯化选育 ,获得具优异性能的突变菌株 ,酶活得到了明显提高更多还原

【Abstract】 According to the conditions designed for tests in the "Shenzhou 4"spacecraft and reqirements of loading, tried a serial experiments for ground simulated test before loading strain of Streptomyces sp. WZFF.L M1 producing microbial transglutaminase (MTG) at the activity of 1.74 U/mL. The spores and mycelia of the strain prepared under the optimal conditions were treated several times by N methyl N’ nitro N nitrosogunidine (NTG) at normal conditions or at a high speed. The results showed that some mutants were different from the original strain in morphology, color and edge of colony, and that these mutation phenomena were related to the MTG productivity and thereafter used for strain selection first. Then, test of flocculation precipitation of proteins through MTG cross linking as the primary screening and examination test of MTG production as the secondary screening were successively used to select potent strains. Some high yield strains were obtained by fermentation screening of many regenerative mutants. The MTG activities of these new mutants were higher than 2.55 U/ml, which had been increased about 40% than that of the initial strain.更多还原