广西眼镜王蛇毒碱性磷脂酶A_2(PLA_2)的分离纯化及其性质的研究

广西眼镜王蛇毒用羧甲基纤维素CM-52、磷酸纤维素P-11和Sepharose CL-6B柱层析纯化,得到一个在聚丙烯酰胺凝胶电泳上为单一蛋白带,PLA_2的比活性较原蛇毒提高3.6倍,分子量的为13000,由122个氨基酸组成,_pI为8.9,具有良好的热稳定性。从碱性PLA_2对红细胞影响的电镜观察可见,对人的红细胞膜有明显的作用,而对山羊红细胞作用不明显。PLA_2无论对人还是对山羊、兔和豚鼠红细胞电泳速度都有明显的迟缓作用。

Isolation, Purifition and Properties of the Alkaline Phospholipase A_2 From the Snake Venom of Ophiophagus Hannah Cantor in Guangxi

Three peaks with phospholipase A2 activity were found by CM-52 cellose column chromatography from the snake venom of Ophiophagus hannah cantor in Gu-angxi. Two of them were first eluted by the equilibrium sodium acetate buffer, being the basic phospholipase A2.This enzyme were further purified by P-cellulose, and Sepharose CL-6B chromatography. The purified protein appeared as a single band on polyacrylamide gel electrophoresis. The specific activity of phospholipase A2 is 3.6 times that of the crude snake venom. It's molecular wight is about 13000, and it's isoelectric point about 8.9. Like the other phospliolipase A2 found in snake venom, the basic phospholipase A2 exhibits extreme heat-stability. Electron microscopic observations on human erythrocytes showed evident changes in the appeara-nce of erythrocyte membrane, but no change was found on goat erythrocytes.