中文摘要：

纤维素酶E4是一种噬温的丝状土壤放线菌Thermomonospora fusca分泌的一种特殊纤维素酶，对细菌微结晶纤维素（BMCC）有较高的活性，可与T.fusca中典型的外切酶和内切酶协同作用。初步研究显示，其不同底物水解活性与结合域（CBD）有很大关系，因此对E4的CBD进行删除，构建4组重组质粒，转入酵母GS115表达系统表达，得到对应重组蛋白。结果显示，CBD的删除对其温度、pH稳定性都有影响，且不同底物的降解活力有明显变化，对于纤维素酶降解机理复杂性有初步研究。

英文摘要：

Cellulose E4 is a special cellulase from Thermomonospora fusca, which has relatively high activity on bacterial microcrystalline cellulose （BMCC） and synergizes with both classes of exocellulases and with endocellulases, but the other endocellulases from T. fusca do not synergize with each other. Initial studies showed that different substrate hydrolysis activity had a great relationship with binding domain （CBD）. So we deleted the CBD and constructed four groups of recombinant plasmids, transferred them to the yeast GS115 expression system, to get the corresponding recombinant protein. The results showed that the deletion of the CBD had an effect on the temperature, pH stability, and different substrate degradation vitality. And reveal the complexity of the cellulase degradation mechanism.