一种快速筛选海藻糖合成酶突变体体系的建立  

Establishment of a quick screening system for trehalose synthase gene mutants

作　　者：李庆业[1] 韦宇拓[1] 王倩倩[1] 刘一[1] 黄日波[1] 

机构地区：[1]广西大学生命科学与技术学院

出　　处：《工业微生物》2008年第3期22-26,共5页Industrial Microbiology

基　　金：国家"973"计划资助项目(2004CB719606)

摘　　要：利用λRed重组系统对大肠杆菌JM109的6-磷酸海藻糖合成酶基因OtsA和6-磷酸海藻糖酯酶基因otsB进行敲除,获得otsA和otsB基因失活的大肠杆菌突变体,该突变体由于对渗透压变得非常敏感,在含5%NaCl和0.5%麦芽糖的培养基中生长缓慢,然而当导入有活力的外源海藻糖合成酶基因后,由于能在胞内合成海藻糖,增强了细胞抗高渗透压培养基的能力,因而可让otsA和otsB基因缺失后的JM109得以恢复其生长能力。通过比较它们在高渗透压的培养基中的生长速度,可以筛选出含有不同活力的海藻糖合成酶突变体。Two chromosomal genes in Escherichia coli JM109 were disrupted by using λ red recombination system, and Escherichia coli mutation with knock-out of the genes OtsA and OtsB was obtained . Yet the mutation was sensitive to the osmotic pressure, so it grew slowly in culture medium containing 5 % NaCl and 0.5 % maltoser. But after transferring the active gene of trehalose synthase, its ability of synthesizing trehalose was recovered and consequently its growth and livingness were recovered. By comparing the growth speeds of the mutations in culture medium with high osmotic pressure, the gene of trehalose synthase mutations with different levels of activity was screened.

关 键 词：λRed重组系统 海藻糖合成酶基因 基因缺失 

分 类 号：Q789[生物学—分子生物学]