不同调控元件驱动下菊欧氏杆菌纤维素酶celY基因在大肠杆菌中表达的研究

目的:以菊欧氏杆菌(Erwinia chrysanthemi)基因组DNA为模板,通过PCR方法找到了该菌的β-1,4-内切葡聚糖酶celY基因及其调控元件并克隆至pUC19载体。为提高纤维素酶celY基因在原核细胞中的分泌表达量,比较了由不同启动子和信号肽调控的celY基因在大肠杆菌中的表达水平。方法:分别构建了由脂蛋白启动子、T7启动子、果胶酶信号肽调控的多种表达载体与由纤维素酶celY基因自身的启动子和信号肽调控的表达载体相比较。结果:由脂蛋白启动子、T7启动子、果胶酶信号肽调控的表达载体都不同程度提高了celY基因的分泌表达量。结论:脂蛋白启动子、T7启动子、果胶酶信号肽都不失为构建强分泌表达载体的可选元件。

Comparison of celY Gene from Erwinia chrysanthemi Expression in Escherichia coli Driven by Different Regulatory Elements

Objective: The celY gene encoding endo-1,4-β-D-glucanase from a strain of Erwinia chrysanthemi was amplified by PCR and cloned into plasmid pUC19.To improve the expression and secretion of CelY,different regulatory elements were compared in driving the expression of CelY in Escherichia coli.Methods: A series of celY expression vectors containing different regulatory elements,such as lpp promoter,T7 promoter,pelB signal peptide,which were compared with the regulatory elements of celY,were constructed.Results: The series of celY expression vectors driven by lpp promoter,T7 promoter,pelB signal peptide,in varying degrees,increased the secretion expression level of CelY.Conclusion: The lpp promoter,T7 promoter,pelB signal peptide could be considered as candidates for the construct of a high-effective secretion vector.