Cloning, expression and characterization of novel helicobacter pylori differentiating antigen - Heat shock protein 20

Abstract

Heat shock protein has been reported as a virulence factor of Helicobacter pylori. A 20kDa heat shock protein (HSP20) of H. pylori identified in this study was found to localize on the cell surface of H. pylori using Western blotting and immuno-gold labeled transmission electron microscopy. An hsp20-isogenic H. pylori SS1 was constructed which displayed equivalent in vitro adherence capability as that of the wild type but failed to colonize in the stomachs of BALB/c mice indicating the involvement of HSP20 in H. pylori colonization. By co-immunoprecipitation, unique interaction was shown between HSP20 and CagA revealing a probable chaperonic role of HSP20 in surface presentation of CagA in H. pylori lending its credence as collaborative a??partnera?? in H. pylori infection. DNA and protein sequences demonstrated the simple and unique 3-amino-acid residues (14tha??16th) of HSP20 showing their potential differentiating capability as epidemiological and gastroduodenal diseases marker of H. pylori.