Takada Y, Takada A
Haemostasis. 1987;17(1-2):1-7. doi: 10.1159/000215552.
When Glu-plasminogen (Glu-plg) was activated by various amounts of streptokinase (SK), Km of the hydrolysis of S-2251 by the mixture of Glu-plg and SK did not change, but Vmax increased with an increase in the amount of SK. Since low concentrations of SK-plg complex do not result in its conversion to the SK-plasmin complex by mutual activation, these results seem to suggest that the SK-plg complex may be a better activator when S-2251 is used as a substrate. When Glu-plg was activated by SK in the presence of fibrin(ogen) or its degradation products (potentiating agents), Km did not change with an increase in the concentration of each potentiating agent, but Vmax increased. The effects of potentiating agents on the kcat values of these activators were in the order of fibrin greater than fibrinogen greater than D greater than E.
当不同量的链激酶（SK）激活谷氨酸纤溶酶原（Glu-plg）时，Glu-plg与SK混合物对S-2251水解的Km不变，但Vmax随SK量的增加而增加。由于低浓度的SK-plg复合物不会通过相互激活转化为SK-纤溶酶复合物，这些结果似乎表明，当使用S-2251作为底物时，SK-plg复合物可能是更好的激活剂。当在纤维蛋白（原）或其降解产物（增强剂）存在的情况下，Glu-plg被SK激活时，随着每种增强剂浓度的增加，Km不变，但Vmax增加。增强剂对这些激活剂kcat值的影响顺序为：纤维蛋白＞纤维蛋白原＞D＞E。
