锯鳞蝰蛇毒中纤溶酶——类蝰酶的纯化与特性研究

Purification and characterization of lebetase, a fibrinolytic enzyme from Vipera lebetina (snake) venom.

作者信息

Siigur E, Siigur J

机构信息

Laboratory of Bioorganic Chemistry, Estonian Academy of Sciences, Tallinn, U.S.S.R.

出版信息

Biochim Biophys Acta. 1991 Jul 8;1074(2):223-9. doi: 10.1016/0304-4165(91)90156-b.

DOI:10.1016/0304-4165(91)90156-b

PMID:2065076

Abstract

An anticoagulant proteinase, lebetase, was isolated from the venom of Vipera lebetina by gel filtration and anion-exchange chromatography. The proteinase consists of a single polypeptide chain with a molecular weight of 23,700. Amino acid analysis indicates that lebetase contains 214 residues. It consists of several isoforms in the pH range 4.6-5.4, all having fibrinolytic activity. Lebetase hydrolyzes casein, fibrinogen and fibrin, and oxidized insulin B-chain in the positions Ala14-Leu15 and Tyr16-Leu17. Its fibrinolytic activity is inhibited by EDTA and lost upon heating at 70 degrees C for 10 min. The enzyme readily hydrolyzes the A alpha-chain and more slowly the B beta-chain of fibrinogen. In fibrin, the same chains are attacked. Thus, the enzyme is an A alpha, B beta-fibrinogenase. The fibrinolytic activity of lebetase is direct, without any plasminogen activation. E280 1% is 13.0 for lebetase. The enzyme showed low hemorrhagic activity.

摘要

通过凝胶过滤和阴离子交换色谱法从草原蝰蛇毒中分离出一种抗凝蛋白酶——矛头蝮蛇毒蛋白酶。该蛋白酶由一条分子量为23700的单多肽链组成。氨基酸分析表明矛头蝮蛇毒蛋白酶含有214个残基。它在pH值4.6 - 5.4范围内由几种同工型组成，均具有纤溶活性。矛头蝮蛇毒蛋白酶可水解酪蛋白、纤维蛋白原和纤维蛋白，以及氧化胰岛素B链中Ala14 - Leu15和Tyr16 - Leu17位点。其纤溶活性受EDTA抑制，在70℃加热10分钟后丧失。该酶能迅速水解纤维蛋白原的Aα链，对Bβ链的水解则较慢。在纤维蛋白中，同样的链也会受到攻击。因此，该酶是一种Aα、Bβ纤维蛋白原酶。矛头蝮蛇毒蛋白酶的纤溶活性是直接的，无需任何纤溶酶原激活。矛头蝮蛇毒蛋白酶的E280 1%为13.0。该酶显示出较低的出血活性。