聚乙二醇对大肠杆菌L-天冬酰胺酶的化学修饰

Chemical Modification of Escherichia Coli L-Asparaginase with Polyethylene Glycol

用琥珀酸酐及琥珀酰亚胺两步活化的单甲氧基聚乙二醇对大肠杆菌 L-天冬酰胺酶进行化学修饰。修饰反应的酶活回收率保持在 40 %以上 ,修饰酶的抗热 ,抗胰蛋白酶水解能力有所提高 ,抗原性显著下降。

E.coli L asparaginase was modified with SS PEG [methoxypolyethylene glycolyl succinimidyl succinate] which was prepared in two steps.The modified enzyme activity was maintained 44.52% while the antigenicity was greatly reduced.The modified L asparaginase showed greater resistance to trypsin degradation.