Construction of human sodium-dependent dicarboxylate transporter 2 fusion protein vector and its expression in E.coli

Objective:To observe and indentify the expression of human sodium-dependent dicarboxylate transporter 2 （hSDCT2） gene in E.coli, and isolate and purify its protein product.Methods: With DNA recombinant technique, the recombinant expressive plasmide pGEX-hSDCT2 was constructed and introduced into E.coli. GST-hSDCT2 fusion protein was expressed at the induction of IPTG. After GST-hSDCT2 fusion protein was purified by GST Sepharose 4B affinity chromatography, purified fusion protein was cleaved by Factor Xa and purified by second affinity chromatography. The results were identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis（SDS-PAGE） and Western blotting assay. Results: Recombinant plasmid pGEX-hSDCT2 was successfully constructed. The results of SDS-PAGE and Western blotting assay showed （1） GST-hSDCT2 fusion protein was expressed in E.coli cell, and was produced at a level of 25% of the total cellular protein. （2） After Factor Xa cleavage and second purification, the hSDCT2 protein was obtained. Conclusions: hSDCT2 couble be expressed in E.coli system stably.