Zhong Xiaoyan, Jiao Haomang, Fan Liang, Wu Xiangfu, Zhou Yuancong
Institute of Biochemistry, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, 320 Yue-Yang Road, Shanghai 200031, China.
Protein Pept Lett. 2002 Oct;9(5):427-34. doi: 10.2174/0929866023408580.
To identify the anticoagulant region of the phospholipase A(2) (PLA(2)) from the Agkistrodon halys Pallas (class II), four mutants E53G, W70M, T56K, and D67K were produced according to the prediction from the crystal structure and the sequence comparison of the strong, weak and non-anticoagulant PLA2s. A test of blood clotting revealed that E53G and W70M had lost their effects on the blood clotting, while T56K and D67K had enhanced activity. The four residues are located on the same face in the tertiary structure of this enzyme. The result supported the prediction that there exists an anticoagulant region that is composed of some residues that are close to each other in tertiary structure to form a functional face.
为了从蝮蛇（II类）中鉴定磷脂酶A2（PLA2）的抗凝血区域，根据晶体结构预测以及强、弱和非抗凝血PLA2的序列比较，构建了四个突变体E53G、W70M、T56K和D67K。凝血测试表明，E53G和W70M对凝血失去了作用，而T56K和D67K的活性增强。这四个残基位于该酶三级结构的同一面上。该结果支持了这样的预测，即存在一个抗凝血区域，该区域由三级结构中彼此靠近以形成功能面的一些残基组成。
