Expression of gastric cancer related gene GCRG213 in E.coli and purification of recombinant protein / 解放军医学杂志

ABSTRACT

Objective To express gastric cancer related gene GCRG213 by using thioredoxin fusion expression system, and to prepare human GCRG213 fusion protein. Methods GCRG213 cDNA with complete open reading frame was amplified by PCR from plasmid pGEM-T, and then was cloned into thioredoxin fusion expression vector pET102/D-TOPO. The recombinant plasmid was further transformed into E.coli BL21 strain. After induction with IPTG, the thioredoxin/GCRG213 fusion protein was expressed in E.coli. The product was obtained by means of direct purification from a denaturing polyacrylamide gel. Results SDS-PAGE analysis showed the thioredoxin/GCRG213 fusion protein with relative molecule mass of 29.4kDa was highly expressed. The thin layer gel scanning analysis showed that the yield of GCRG213 fusion protein was 28.7% of the total bacterial protein. The product was obtained with a purity of about 100% by means of direct purification from a denaturing polyacrylamide gel. Conclusion The thioredoxin/GCRG213 fusion protein was successfully expressed in E.coli and the product with high purity was obtained, which laid the foundation for the function research and antibody preparation hereafter.