大肠杆菌错配识别蛋白MutS的表达与活性鉴定

Expression and activity identification of E.coli mismatch binding protein MutS

目的构建表达错配识别蛋白MutS,并进行错配识别活性鉴定。方法在大肠杆菌中表达MutS蛋白,并纯化获得目的蛋白;利用凝胶滞缓实验对错配识别活性进行验证,并计算MutS蛋白降低的错配率。结果纯化的MutS蛋白具有错配识别活性,并能降低DNA双链的错配率。结论表达纯化的MutS蛋白在体外具有特异性识别、结合含有错配碱基DNA双链的生物活性,从而有助于合成生物学的发展。

Objective To construct a vector which can successfully express mismatch recognition proteins called MutS and identify the activity of mismatch recognition.Methods MutS protein was exprssed in Escherichia coli and purified.The biological activity of the protein was identified by gel retardation assay and the mismatch rate reduced by MutS protein calculated.Results The purified MutS protein had mismatch binding activity and could reduce the mismatch rate of double-stranded DNA.Conclusion The purified MutS protein has biological activities of specific identification and combining with double-stranded DNA containing mismatch base in vitro,contributing to the development of synthetic biology.