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.
出处
《食品工业科技》
CAS
CSCD
北大核心
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)
