Cloning and Expression of Mycobacterium Tuberculosis ESAT-۶ in Prokaryotic System

The identification of a large number of antigens with potential for development of new tuberculosis vaccine has been accomplished in recent years. This study was designed for cloning and expression of ESAT-۶ as a potent antigen of Mycobacterium tuberculosis. Selected gene (Rv۳۸۷۵) was amplified by PCR and product was ligated into expressing plasmid vector pQE۳۰ and recombinant pQE۳۰-ES plasmid was constructed. This hybrid vector was transformed in E. coli M۱۵ and expressed in optimal condition. The expressed protein was analyzed on SDS-PAGE and confirmed by western blotting using specific antisera to ESAT-۶. We successfully cloned and expressed ESAT-۶ (His)۶ from M. tuberculosis H۳۷Rv genome. As well as usage for serodiagnosis, this recombinant protein offers the potential development of other vaccine formats such as DNA or subunit vaccines against tuberculosis.