腈水合酶固定化方法和催化特性的研究

Study on the Immobilization and Catalytic Behavior of a Hydration Enzyme

以一种能够产生腈水合酶诺卡氏菌为研究对象，针对原来的海藻酸盐包埋法存在的固定化细胞强度较小、通透性较差等问题，改进了对酶的固定化方法，并对固定化腈水合酶的催化特性：最适反应温度、pH值、底物丙烯腈浓度、和表面活性剂性质和丙烯酰胺累积浓度对酶活性的影响等五个方面进行了研究。其中固定化腈水合酶最适反应温度在15～25℃；pH7．0左右；底物丙烯腈浓度为3％-4％；Triton X-100对酶活性基本无影响，而Tween 80和Tween 60对酶活力有抑制作用；固定化腈水合酶在丙烯酰胺累积浓度为15％-20％之间时，酶活性较好。

A kind of nocardia asteroides which can produce the acrylonitrile hydration enzyme was studied. The method of immobilization of the enzyme was improved and the suitable catalytic reaction conditions were found. The optimum reaction conditions are ： temperature, 15 - 25℃ ; pH value, 7.0 ; concentration of acrylonitrile, 3 % - 4 %, Triton X-100 does not affect the activity of the hydration enzyme, but Tween 80 and Tween 60 inhibit the activity of the hydration enzyme. The activity of the hydration enzyme is higher when the concentration of acrylamide is 15 % - 20 %.