Kajihara J, Shibata K, Kato K
Development Laboratory, JCR Pharmaceuticals Co., Ltd., Kobe, Japan.
Biosci Biotechnol Biochem. 1997 Jan;61(1):197-8. doi: 10.1271/bbb.61.197.
Human urokinase (UK) was easily degraded during the incubation at 37 degrees C in a time-dependent manner. The degradation was also observed in the presence of trypsin inhibitors, suggesting that UK was not degraded by exogeneous trypsin-like serine protease but by autolysis. In this cases, the A-chain of UK was selectively degraded. Polyethylene glycol-polypropylene glycol conjugated urokinase (PEG-PPG-UK) was not degraded after prolonged incubation at 37 degrees C. These results demonstrated that PEG-PPG modification completely blocked the degradation of UK by autolysis.
人尿激酶（UK）在37℃孵育期间容易随时间依赖性降解。在存在胰蛋白酶抑制剂的情况下也观察到这种降解，这表明UK不是被外源性类胰蛋白酶丝氨酸蛋白酶降解，而是通过自溶降解。在这种情况下，UK的A链被选择性降解。聚乙二醇-聚丙二醇缀合尿激酶（PEG-PPG-UK）在37℃长时间孵育后未降解。这些结果表明，PEG-PPG修饰完全阻断了UK的自溶降解。
