Cloning and Expression of the Ag85B Protein from Mycobacterium Tuberculosis

Objective To clone and express Ag85B,and to evaluate the feasibility of the recombinant protein as a diagnosis antigen. Methods The piece of genes coding Ag85B was obtained by PCR method.Recombinant plasmid was constructed, then, transformed into E.coli BL21 strain, and induced by IPTG.The expression product was analyzed with Western-blot method. Results The recombinant protein expressed in host bacteria was effective .By means of western-blot assay it was showed that immunological response was good. Conclusion The recombinant Ag85B has the better immunoreactivity, and it′s feasible to be a diagnostic antigen or a new vaccine.