北京大学学报(自然科学版)

含RGD序列水蛭素嵌合抗栓剂的构建与表达

周雪,黄仪秀,朱圣庚   

  1. 北京大学生命科学学院,北京,100871
  • 收稿日期:2000-05-15 出版日期:2001-07-20 发布日期:2001-07-20

Construction and Expression of Chimeric Antithrombotics with Hirudin and RGD Sequence

ZHOU Xue,HUANG Yixiu,ZHU Shenggeng   

  1. College of Life Sciences, Peking University, Beijing, 100871
  • Received:2000-05-15 Online:2001-07-20 Published:2001-07-20

摘要: 通过对水蛭素及一些含有精氨酸-甘氨酸-天冬氨酸(RGD)序列的多肽类血小板聚集抑制剂结构与功能的分析,设计并构建了两个在水蛭素C端融合RGD序列的嵌合分子。嵌合体基因分别重组到表达载体pET-21a(+)中并转化大肠杆菌BL21(DE3)。经限制酶消化和DNA序列分析,证明两种重组质粒与设计完全一致。由于RGD-水蛭素嵌合基因上游连接了金黄色葡萄球菌蛋白A(SPA)的信号肽序列,在IPTG诱导下两种嵌合分子都获得了分泌表达,表达产物主要集中在细胞周质空间。通过离子交换层析和凝胶过滤层分别对两种嵌合体蛋白进行纯化,纯化产物在Tricine-SDS-PAGE中都显示为单一条带。活性分析结果表明两种嵌合体蛋白在保留水蛭素抗凝血酶活力的同时,还呈现抗血小板聚集活性。

关键词: 水蛭素, RGD序列, 嵌合抗栓剂

Abstract: Based on the structure and function analysis of hirudin, a potent thrombin inhibitor, and some platelet aggregation inhibitors, which contain the recognition sequence Arg-Gly-Asp(RGD)as their functional motif, two chimeric antithrombotic molecules were designed by introducing RGD sequence to hirudin C terminus. These chimera genes were constructed by PCR and inserted into the expression vector pET-21a(+), the constructs were confirmed by restriction enzyme digestion and DNA sequence analysis. These recombinant plasmids were transformed into E.coli strain BL21(DE3), and gene expression was induced by IPTG. The target proteins were directed into the periplasmic space by the staphylococcal protein A(SPA)signal sequence preceding the RGD-hirudin gene. Using ion exchange chromatography and gel filtration chromatography, the chimera proteins were purified, and both of them showed a single band in Tricine-SDS-PAGE.The results of activity analysis suggested that these two chimera proteins not only have antithrombin activities, but gain platelet aggregation inhibitory activities as well.

Key words: hirudin, RGD sequence, chimeric antithrombotic

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