摘要
本文介绍用β-硫酸酯乙砜基苯胺(SESA)活化右旋糖酐T2000以修饰大肠杆菌5852青霉素酰化酶。活化时500mg右旋糖酐需SESA 20mg。制备对氨基苯磺酰乙基葡聚糖(ABSE)-右旋糖酐的反应温度为80℃,与500mg活化右旋糖酐偶联的酰化酶酶量为100u,修饰率达88.3%。用琼脂糖(Sepharose 4B)或交联葡聚糖(Sephadex G150)柱层析分离得高分子量的修饰酶。修饰酶对热和pH的稳定性均优于自由酶,最适温度提高,但最适pH和高浓度青霉素G底物抑制现象没有改变。
E. coli 5852 penicillin acylase is modified by dextran T 2000 activated by β-sulphate ethyl sulfonyl aniline (SESA). The amount of SESA used for activation of 500mg dextran T 2000 is 20mg. The dextran activation temperature is 80℃. The modification efficiency is 88.3%. The modified enzyme can be effectively separated from the native enzyme by means of Sephadex G150 chromatography. The molecular weight, heat-and pH-stability as well as the optimum temperature of the modified enzyme are greatly increased, but the optimum pH and high penicillin concentration inhibition effect are not improved.
关键词
酶
青霉素G
修饰
修饰酰化酶
enzyme
penicillin
modification
dextran
penicillin acylase
modified acylase.
