热纤梭菌内切β-1,4-葡聚糖酶的克隆与表达

Cloning and Expression of the Thermostable Endoglucanase Gene of Clostridium thermocellum

将来源于热纤梭菌(Clostridium thermocellum)ATCC 27405的编码内切β-1,4-葡聚糖酶的结构基因(celD)与热激表达载体pHsh连接,得到重组表达载体pHsh-celD,并将重组表达载体pHsh-celD转入到大肠杆菌Escherichia coli BL21-CodonPlus(DE3)-RIL中。结果表明,该重组酶的分子质量为66 ku,与预期大小相符。基于表达载体pHsh的重组表达系统具有诱导表达简便、诱导方式廉价的优点,且重组酶热稳定性非常好,对该酶的大规模发酵应用具有重要意义。

The structure gene from Clostridium thermocellum ATCC 27405 encoding endoglucanase gene was amplified and ligated into pHsh,resulting in pHsh-celD.Cellulase was obtained after expression pHsh-celD in Escherichia.coli BL21CodonPlus （DE3）-RIL.The results showed that the molecular mass of the expressed recombinant CelD was about 66 kD,which was exactly the predicted size.The expression vector system of the heat shock plasmid pHsh had advantages of high expression level and cheap induction.The superior stability of the recombinant enzyme will be valuable for large-scale fermentation of this enzyme.