Sheehan H, O'Kennedy R, Kilty C
School of Biological Sciences, Dublin City University, Glasnevin, Ireland.
Biochim Biophys Acta. 1990 Nov 15;1041(2):141-5. doi: 10.1016/0167-4838(90)90057-m.
Dimeric bovine heart creatine kinase (EC 2.7.3.2, ATP: creatine N-phosphotransferase) has been cross-linked with the bifunctional reagent dimethyl suberimidate at several concentrations to yield modified enzyme with enhanced stability towards heat denaturation. The degree of thermal stability is dependent on the degree of cross-linking with optimal stabilization occurring when approx. half of all the available amino groups are covalently attached to dimethyl suberimidate. Accelerated storage studies were performed and the results used to predict the storage time of the native and modified enzyme at lower temperatures. The cross-linked derivative was predicted to have a longer shelf-life at 4 degrees C than the native enzyme. Modification caused a reduction in the specific activity of the enzyme. The pH profile was altered following cross-linking, but the Michaelis constants were not changed. The modified enzyme exhibited a marked resistance to the action of some denaturing agents.
二聚体牛心肌酸激酶（EC 2.7.3.2，ATP：肌酸N-磷酸转移酶）已与双功能试剂亚辛二酸二甲酯在几种浓度下进行交联，以产生对热变性具有更高稳定性的修饰酶。热稳定性的程度取决于交联程度，当大约一半的可用氨基共价连接到亚辛二酸二甲酯时会出现最佳稳定性。进行了加速储存研究，并将结果用于预测天然酶和修饰酶在较低温度下的储存时间。预计交联衍生物在4℃下的保质期比天然酶更长。修饰导致酶的比活性降低。交联后pH曲线发生了变化，但米氏常数没有改变。修饰酶对某些变性剂的作用表现出明显的抗性。
