利用Zeta电位仪对带电蛋白质表面的Zeta电位进行测量,在不同浓度梯度的还原型谷胱甘肽、牛血清蛋白和两种蛋白的混合溶液中分别加入α-淀粉酶,测定目标酶系的活性、米氏常数、活化能等参数.结果表明,分别加入浓度为0.6 mmol/L还原型谷胱甘肽、牛血清蛋白和两种蛋白的混合溶液的酶活力分别提高7.9%、8.7%、11.1%,米氏常数从129.7g/L分别降低至116.0、104.2、85.1g/L,最大反应速率从32 g/(L?min)分别降至30.50、28.10、23.79 g/(L?min),活化能从13.91 kJ/mol分别降至10.00、9.91、9.88 kJ/mol.这种改变与蛋白质的浓度呈正相关,线性关系良好.说明不同带电蛋白质的加入使α-淀粉酶的活性增大,酶与底物的亲和力增加,反应速率加快,效率更高.%Zeta potential was measured to study the effect of charged proteins on α-amylase and its enzymatic reaction.α-amylase solution was added into reduced glutathione (GSH) , bovine serum albumin (BSA) and the mixture of two proteins with different concentrations. The activities , kinetic parameters and activation energies were determined.The results showed that the activities were increased by 7.9% ,8.7% and 11.1% respectively at the concentration of 0.6 mmol/L.The kinetic parameters of Km decreased from 129.7 g/L to 116.0 ,104.2 ,85.1 g/L ,while Vm decreased from 32 g/(L · min) to 30.5 , 28.1 ,23.7 g/(L · min) ,respectively.The activation energies decreased from 13.91 kJ/mol to 10.00 ,9.91 and 9.88 kJ/mol.The change inα-amylase is positively correlated with the protein concentration and has a good linear relationship.T he results indicated that the activity of α-amylase and the affinity of enzyme and substrate increased ,the reaction rate was accelerated and the efficiency was improved.
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