Pili-related Genes in Mycobacteriumtuberculosis

Introduction and Objective: Mycobacterium tuberculosis is responsible for nearly 3 million human deaths worldwide every year. Many bacterial pathogens use pili as adherence factors to colonize the host. Purified M. tuberculosis pili (MTP) are composed of low-molecular-weight protein subunits encoded by the predicted M. tuberculosis H37Rv ORF, designated Rv3312A .which is known as Flp with a molecular weight of 150 bp. It is comprised of 6-kDa protein subunits encoded by the M. tuberculosis H37Rv predicted open reading frame, designated Rv3656c.The aim of this study on M. tuberculosis pili, is to highlight their structure and biological significance to M. tuberculosis pathogenesis, and discuss their potential as targets for therapeutic intervention and diagnostic test development. Understanding the mechanisms and bacterial factors responsible for the ability of M. tuberculosis to cause disease in humans is critical for the development of improved treatment strategies. Materials and Methods: PCR and sequencing were used to investigate two related pili, Mtp and Flp genes in clinical isolates of M. tuberculosis H37RV, MDR, TDR and XDR. The primers were designed and PCR program was set for whole genes amplification. Subsequently, the amplicons were digested with three restriction enzymes, namely TaqII, Acil and HaeII for a 150bp region of flp genes, Mspji, Fnu4hi and XmaIfor a361bp region of mtpgenes . Results: Electrophoresis revealed two specific bonds of 361 bp for Mtp and 150 bp for Flp genes and confirmed primer and PCR conditions designing. The purified PCR fragments were digested with the mentioned enzymes and compared with MDR,TDR and XDR isolates. Conclusion: Two genes of pili in all clinical isolates of M. tuberculosis were conserved and two morphological types of pili were detected. We proposed that by targeting pili proteins can prevent the phatogenesis of Mycobacterium, especially in its resistant forms.