Construction and expression of fusion expression vector of Escherichia coli LTB and Helicobacter pylori HSPA

Objective To construct a fusion expression vector of Escherichia coli heat labile enterotoxin B subunit. Methods Gene encoding LtB without signal peptide and stop codon was added to the linker TAPI by PCR. It was cloned into PinPoint TM Xa Ⅲ with Pst Ⅰ and BamH Ⅰ sites. The recombinant plasmid was transfected in E.coli JM109. The expression of LTB was analysed by SDS PAGE and Western blot. Results The fusion expression plasmid was successfully constructed. The subunit A of heat shock protein of Helicobacter pylori was fused with LTB and expressed, and display both the ability of binding GM 1 and the immunogenicity with polyclonal antibodies against H. Pylori . Conclusion The vector founds a basis for the study of intramolecular adjuvant.