Objective To prepare the polyclonal antibody against heat shock protein ClpE of Streptococcus pneumoniae(S. pn),and determine its subcellular location in S. pn. Methods Full length ClpE gene of S. pn D39 was amplified by PCR and cloned into prokaryotic expression vector pET28a. The constructed recombinant plasmid pET28a::ClpE was transformed to E. coli BL21(DE3)and induced by IPTG. The expressed product was purified by affinity chromatography, with which BALB / c mice were immunized. The prepared polyclonal...