Cloning and Secretion Expression of Heat-shock Protein 70 Gene of Helicobacter pylori

Heat-shock protein 70 gene (hsp70)was obtained by PCR method from Helicobacter pylori chromosomal DNA. Sequencing analysis exhibited that the hsp70 gene isolated from Hp Y(2) was highly homologous with the gene encoded in Helicobacter pylori 26695 and J99, which had been sequenced for complete genome. The hsp70 gene was recombined in vitro with fusion secretion expression vector pMAL-p2 and was transformed into E.coli cells. The E.coli strains, containing hsp70 recombinant plasmid, expressed a 113 kD fusion protein which accounted for 19.4% of the total bacterial periplasm protein after the induction with IPTG for 5 h at 30 degrees. The expressed fusion protein could react specifically with anti-Helicobacter pylori rabbit IgG, as proved by Western blot method.