氨基树脂固定胃蛋白酶的方法及性质研究

采用氨基树脂作为载体,戊二醛作为交联剂,对胃蛋白酶的固定化进行了研究,并对固定化条件和固定化胃蛋白酶的部分酶学性质进行了分析。确定固定条件为：戊二醛浓度为5%,载体处理温度为室温（25℃）,处理时间为5h,m（胃蛋白酶）：m（氨基树脂）为1：25,pH为3.0,固定时间为12h。此条件下固定化的胃蛋白酶活力为30U/g,酶的活力回收率为60%。与非固定化相比最适水解温度由50℃升高到60℃,最适pH值由2.0升高到4.0,游离酶米氏常数3.08g/L,固定化酶米氏常数1.2g/L,固定化胃蛋白酶的储存半衰期约为25天。对珠蛋白的操作半衰期为9天。

Study on immobilization method and characters of pepsin by amino resin

The immobilization of pepsin was studied by using amino resin as immobile carrier and glutaraldehyde as crosslinking agent.Immobilization method,immobilization condition and some characterization of immobilized pepsin were also studied.The optimal conditions of immobilization are as following：amino resin was treated with 5%glutaraldehyde for 5h at room temperature（25℃）,then m（pepsin）：m（amino resin）was 1：25,immobilized on the carrier for 12h at pH=3.0.Immobilized pepsin activity was about 30U/g,and activity recovery was about 60%.Optimal reaction temperature of the pepsin raised from 50℃to 60℃,the optimal reaction pH of immobilized pepsin was 4.0 and that of free pepsin was 2.0.The Michaelis constant reduced from 3.08 g/L to 1.2 g/L.The storage half-life was about 25 days.The operating half-life was about 9 days.