摘要
借助于ＳＤＳ－聚丙烯酰胺凝胶电泳分析方法，对乳糖诱导的由乳糖启动子控制的大肠杆菌ＲＮＡ聚合酶σ７０因子基因表达过程进行了优化研究．结果表明，含此融合基因的大肠杆菌菌株ＢＬ２１（ＤＥ３）ｐＧＥＭＤ的生长量达到ＯＤ６００ｎｍ＝１．０时，用终浓度为０．０８％的乳糖进行连续５ｈ的诱导，可使大肠杆菌ＲＮＡ聚合酶σ７０因子基因的表达量达到最大，并达到ＩＰＴＧ同样的诱导效果．流加低浓度的乳糖溶液能增加σ７０因子的合成量，但是促进作用不很显著．
The optimization of lactose induced over expression of the cloned Escherichia coli RNA polymerase σ 70 factor gene in Escherichia coli strain BL21(DE3) was reported. It was found that the expression level of σ 70 factor gene inserted on a phagemid pGEMEX, was the highest when the strain BL21(DE3) harboring the phagemid was induced for 5 h with 0.08% of lactose at a growth level of OD 600 nm = 1.0. Feeding lactose solution in a lower concentration at an interval of 30 min. into the bacterial culture at the optimal growth level could slightly promote the synthesis of σ 70 factor.
出处
《武汉大学学报（自然科学版）》
CSCD
1998年第4期513-510,共1页
Journal of Wuhan University(Natural Science Edition)
基金
国家教委留学回国人员基金
关键词
乳糖诱导作用
启动子
基因表达
lac promotor,gene expression,lactose as an inducer
