蔗糖及麦芽糖对蛋白酶的保护机理研究

Study on the Protection Mechanism of Protease by Maltose and Sucrose

研究了二糖类对J6菌所产蛋白酶的保护作用.结果显示:麦芽糖和蔗糖对蛋白酶活性都有较好的保护作用,蔗糖更佳.但是增加蔗糖的含量并不能提高保护效果,说明实现对酶分子的"包覆"所需要的糖分子个数是有限的.此外,对实验数据按照两步失活动力学模型进行非线性拟合,图形显示拟合效果良好,同时得到酶的失活速率常数和半衰期t,加入麦芽糖和蔗糖之后,蛋白酶的半衰期分别增长了3.5和53倍,为该蛋白酶的工业应用奠定了基础.

The protective effect of the two sugars on the homemade protease was studied. It was showed that the protease activity was well protected by Maltose and Sucrose. Sucrose was better. But,increasing the sucrose content cannot improve the protective effect,due to the lirit of the number of sugar molecules of protein molecules ＂coated＂. In addition,thermal deactivation kinetics of proteasewas analyzed in the absence and in the presence of Maltose and Sucrose. Suitable mechanism was proposed to describe the deactivation process. In the presence of Maltose and Sucrose,the protease half-lives increased 3. 5-and 53-fold,respectively.