cloning and expression of mycobacterium tuberculosis esat-6 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-6 as a potent antigen of mycobacterium tuberculosis. selected gene (rv3875) was amplified by pcr and product was ligated into expressing plasmid vector pqe30 and recombinant pqe30-es plasmid was constructed. this hybrid vector was transformed in e. coli m15 and expressed in optimal condition. the expressed protein was analyzed on sds-page and confirmed by western blotting using specific antisera to esat-6. we successfully cloned and expressed esat-6 (his)6 from m. tuberculosis h37rv 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.