Cloning and fusion expression of HBV PreS gene and its purification using affinity chromatography

AIM To search the novel protein interacted with HBV PreS so as to further study its function and mechanism. METHODS Firstly we cloned the gene of PreS. After sequencing cloned it into the expressing vector pRSET C, itwas transfected into the host strain E.coli JM109 (DE3). After 3 hours induction with IPTG, the strain controlled by T7 promoter expressed the fused PreS protein with a hexahistidine tail in its N terminal. We purified the target protein under denaturing condition. RESULTS SDS PAGE analysis showed that the fusion protein mainly existed in inclusion bodies. We isolated the inclusion bodies from the culture, then purified the fusion protein under denaturing condition using metal chelate affinity chromatography. The purity of HBV PreS was up to 90%. CONCLUSION Construction of the recombinant expressing plasmid lays a basis for further study of the PreS protein.