人转化生长因子β1在大肠杆菌RR1中的表达及产物纯化

Expression and purification of human transforming growth factor β1 in E.coli RR1

目的 :构建能高效表达人转化生长因子 β1的基因工程菌 ,优化产物分离纯化的条件 .方法 :用PCR方法扩增人转化生长因子 β1的cDNA ,将该cDNA片段插入经改造的pBV 2 2 0表达载体pBL 2的表达框架中 ,构建了表达菌株RR1/pBL 2 -TGF - β1.4 2℃温控诱导表达 .采用谷胱甘肽法 ,对重组蛋白进行复性 .通过阳离子交换、变性分子筛层析纯化重组蛋白 .用MTT法测定重组蛋白的活性 .结果 :所构建的表达菌株 ,其TGF - β1的表达量约为 15 %.重组蛋白的复性率达到30 %.经纯化获得了银染一条带的重组蛋白 .测活表明重组蛋白具有较强的生物活性 .结论 :人转化生长因子β1在大肠杆菌RR1中实现了高效表达 ,获得了具有生物活性的重组TGF - β1.

Aim: High level expression system of human transforming growth factor β1 was constructed. Methods: TGF-β1 cDNA produced by PCR was cloned into the expression vector pBL2. The expression was induced at 42℃. The expressed TGF-β1 was renatured by gluathion method and purified by ionic exchange and molecular sieve chromatography from the inclusion body of bacteria lysate. Results: The expression level of the recombinant TGF-β1 in Escherichia coli RR1 was about 15%. The purified TGF-β1 has potential biological activity. Conclusion: Biologically active TGF-β1 was produced in high yield in Escherichia coli RR1.