ABSTRACT
Objective To express the plasminogen activator(Pla) of Yersinia pestis and one of its gene fragments,and to detect their immunological reactivity.Methods The pla gene and its specific gene fragment pla-c were amplified by PCR using the EV76 strain as a template.PCR products were then ligated with the plasmid pET32a (+).The recombinant plasmids pET32a (+)-pla and pET32a (+)-pla-c were subsequently trausformed into E.coli BL21 (DE3).The expressed products were purified by HIS affinity chromatography,and their immunological reactivity was detected by Western blotting.Results The recombinant Pla(52.8 × 103) was expressed as inclusion bodies,and the recombinant Pla-c protein (24.0 × 103) was expressed in the soluble form.These two recombinant proteins reacted with anti-Yersinia pestis EV76 rabbit sera.Conclusions The recombinant Pla and its specific fragments have displayed immunological reactivity,and can be served as an alternative diagnosis method for Yersinia pestis.