紫外-亚硝基胍复合诱变筛选高产淀粉酶菌株  

Screening of high amylase-producing strains by mutagenesis with ultraviolet ray and nitrosoguanidine

作　　者：李旭媛[1] 王刚[1] 费卓群[1] 陈光[1] 

机构地区：[1]吉林农业大学生命科学学院,长春130118

出　　处：《中国生物制品学杂志》2012年第11期1543-1546,1549,共5页Chinese Journal of Biologicals

基　　金：吉林省科技发展计划项目(20100226)

摘　　要：目的经紫外-亚硝基胍(NTG)复合诱变选育高产淀粉酶菌株。方法以蜡状芽孢杆菌SWWL06(Bacillus cereusSWWL06)为出发菌株,分别经紫外、亚硝基胍(NTG)诱变原始菌株,获得最佳诱变条件;经紫外-NTG复合诱变,所得突变菌株以透明圈与菌落直径比值大小进行初筛,再经摇瓶培养进行复筛,得高产淀粉酶突变株;连续传代,检测其遗传稳定性。结果确定紫外波长254 nm,照射时间120 s,垂直照射距离20 cm为最佳紫外诱变条件;NTG浓度为0.5 mg/ml,诱变时间40 min为最佳NTG诱变条件;紫外-NTG复合诱变筛选出9株突变株,其中UV-NTG-3酶活力为3.515 U/ml,增幅最高,较原始菌株SWWL06提高3.59倍;将UV-NTG-3连续传代10次,酶活性仍可达到第一代的97%。结论已成功选育出1株高产淀粉酶菌株UV-NTG-3。Objective To screen high amylase-producing strains by ultraviolet ray（UV） and nitrosoguanidine（NTG）.Methods Bacillus cereus SWWL06 as an original strain was induced with UV and NTG respectively,of which the condition was optimized.The strains obtained by mutagenesis with UV-NTG were preliminarily screened according to the ratio of diameter of clear zone to that of colony,and further screened by culture in shake-flask.The obtained high amylase-producting mutants were subcultured continuously and determined for genetic stability.Results The optimal wavelength,time and vertical distance for mutagenesis by UV were 254 nm,120 s and 20 cm respectively.However,the optimal concentration and time for mutagenesis by NTG were 0.5 mg / ml and 40 min respectively.Nine mutants were screened by mutagenesis with UV-NTG.The amylase activity of mutant UV-NTG-3 was 3.515 U / ml,which increased by 3.59 folds as compared with that of original strain SWWL06.However,the amylase activity of mutant UV-NTG-3 after subculture for 10 passages was still 97% of that of the mutant of passage 1.Conclusion A high amylase-producing strain UV-NTG-3 was successfully screened.

关 键 词：蜡状芽孢杆菌 淀粉酶 紫外诱变 亚硝基胍诱变 

分 类 号：TS201.3[轻工技术与工程—食品科学] TS23[轻工技术与工程—食品科学与工程]