Prokaryotic expression and biological functions of Mycobacterium tuberculosis Rv1884c and Rv0867c genes

Abstract

Objective To construct fusion gene and prokaryofie expression plasmid encoding the Rv1884c and Rv0867c genes in Mycobacterium tuberculosis (M.tb).The fusion protein wsg expressed efficienfly in E.coli cells.Methods The Rv1884c and Rv0867c genes were amplified by polymerase chain reactions (PCR) with specific primers from genomic DNA of M.tb H37Rv strain,and cloned into pGEX-4Tland pUC19 vectors.Rv1884c and Rv0867c were subcloned into the expression vector pGEX-4T-1 and pPRO-EXHT followed by DNA sequencing.The plasmids were transformed into E.coli DH5α and induced to produce GST-fused Rv1884c and His-fused Rv0867c fusion protein.The protein molecular weight and expression format was analyzed by SDS-PAGE.Results The recombinant expressive vectors pGEX-4T-1Rv1884c and pPRO-EXHT-Rv0867c were constructed.The DH5α strains of E.coli with recombinant plasmid showed high level of Rv1884c and Rv0867c gene expressions after IPTG induction.The SDS-PAGE showed that the plasmids expressed Rv1884c and Rv0867c fusion proteins with molecule weight of 45 000 and 80 000.The recombinant protein accounted for 18.3%and 23.7%of total bacteria protein.The expressed proteins could be purified via GSTrao FF and Ni2+-NTA system kits in denatured condition.Conclusions Mycobacterium tuberculosis Rv1884e and Rv0867c genes have been cloned and expressed Successfully in E.coli DH5α.The results lay a basis for further study of fast culfivation in Mycobacterium tuberculosis and investigation of their activities and functions. Key words: Myeobacterium tuberculosis; Bacterial proteins; Recombinant fusion proteins; Cytokines; Gene expression