重组β-葡萄糖苷酶基因和内切葡聚糖苷酶基因在大肠杆菌中的共表达  

The co-expression of beta-glucosidase gene and endo-glucanase gene in Escherichia coli

作　　者：唐自钟[1] 刘姗[1,2] 韩学易[1] 陈惠[1] 孙蓉[1] 单志[1] 苟琳[1] 吴琦[1] 

机构地区：[1]四川农业大学生命科学与理学院,四川雅安625014 [2]攀枝花学院生物与化学工程学院,四川攀枝花617000

出　　处：《食品工业科技》2013年第24期189-194,共6页Science and Technology of Food Industry

基　　金：四川省科技厅科技支撑项目(2008Z0150)

摘　　要：β-葡萄糖苷酶和内切葡聚糖苷酶是纤维素酶的重要组分，多基因的共表达在各领域有重大的应用价值，本研究利用pET32a和pET30b两个载体的不同抗性的特性，在大肠杆菌中将β-葡萄糖苷酶基因和内切葡聚糖苷酶基因，实现了不相容性共表达，获得了产两种酶的工程菌，酶活力可达1196．8U／mL。比单一酶组分的酶活力高，酶学性质分析显示共表达酶的最适反应pH为6．0，最适反应温度60℃，在pH5-7范围内能保持较高活性，酶活可达最高酶活的80％以上，在30～60％范围能有较高的温度稳定性，酶活维持在80％以上。这一结果将为工业应用的进一步研究提供理论基础。β-glucosidase enzyme gene and endo-glucanase enzyme is an important component of cellulase. Co-expression is convenient method and has great economic value. A simple and visible assay was described,in which two incompatible plasmids （pET32a and pET30b）,separately carrying the BGL gene and EG gene,were co-transferred into E. coll. After the induction of lmmol/L IPTG,cellulase activity of the expression strain could reach 1196.8U/mL. The recombinant protein had an optimum catalytic activity at pH5.0 and 60℃. The recombinant enzyme was relatively stable in a broad pH range,from 5.0 to 7.0 and retained 80% activity. The enzyme was stable between 30 to 60℃ ,and retained 80% activity. This research could provide the basis for the further investigations of cellulose.

关 键 词：Β-葡萄糖苷酶 内切葡聚糖苷酶 共表达 酶活 酶学性质 

分 类 号：Q814[生物学—生物工程]