水蛭素12肽与低分子量尿激酶融合基因的构建和表达

Construction and expression of the fused gene of hirudin 54-65 and low molecular singlechain urokinasetype plasminogen activator

目的：旨在获得既能抗栓又能溶栓的双功能蛋白，并在大肠杆菌中表达。方法：化学合成水蛭素１２肽基因编码序列。通过ＤＮＡ重组技术将水蛭素１２肽基因片段连接到低分子量尿激酶ｃＤＮＡ片段５′端，构建成融合基因。结果：构建了水蛭素１２肽与低分子量尿激酶的融合基因，在大肠杆菌中获得表达。重组融合蛋白具有溶栓与抗栓双功能。结论：运用ＤＮＡ重组技术可将两种不同功能的蛋白合理地融合在一起，使其具有溶纤活性和抗凝活性。

Objectives: To obtain an E.coli strain that can express a bifunctional protein with both fibrinolytic and anticoagulant activities. Methods: To synthesize chemically the encoding sequence of the COOHterminal 12 aa of hirudin. Construct a chimeric gene by fusing the hirudin 12 aa gene segment with the 5′ end of the cDNA of low molecular singlechain urokinasetype plasminogen activator. Results: A fused gene of the 12 aa of the COOHterminal of hirudin and the low molecular singlechain urokinasetype plasminogen activator was constructed and expressed in E.coli. The fused protein had both fibrinolytic and anticoagulant activities. Conclusion: By DNA recombination technique, two proteins with different functions can be properly fused to get both fibrinolytic and anticoagulant activities.