Characterizing the Mycobacterium tuberculosis Rv2707 protein and determining its sequences which specifically bind to two human cell lines

Abstract

The Rv2707 gene encoding a putative alanine-and leucine-rich protein was found to be present in all Mycobacterium tuberculosis complex strains (by PCR) and its transcription was shown by RT-PCR in all but M. bovis and M. microti. Antibodies raised against Rv2707 peptides specifically recognized the native protein by Western blot and were able to locate this protein on the M. tuberculosis membrane by immunoelectron microscopy. A549 and U937 cells lines were used in binding assays involving synthetic peptides covering the whole Rv2707 protein. ) presented high specific binding to both A549 and U937 cells. Cross-linking assays revealed that peptide 16084 specifically bound to a 40-kDa and a 50-kDa U937 cell membrane protein. High activity binding peptides (HABPs) 16083 and 16084 were able to inhibit M. tuberculosis invasion of A549 cells. Our results suggest that these sequences could be part of the binding sites used by the bacillus for interacting with target cells, and thus represent good candidates to be tested in a future subunit-based, multiepitope, antituberculosis vaccine.

Peptides derived from Mycobacterium tuberculosis Rv2301 protein are involved in invasion to human epithelial cells and macrophages

“…interaction and complement previous studies reported by our group (Chapeton-Montes et al 2008b;Plaza et al 2007;Vera-Bravo et al 2005). The same highly sensitive and robust methodology has been used to identify and characterize amino acid sequences mediating binding interactions with target cells, and that have the ability to inhibit mycobacterial invasion.…”

Mycobacterium tuberculosis Rv0679c protein sequences involved in host-cell infection: Potential TB vaccine candidate antigen

“…Rv0679c HABPs were assessed for their ability to inhibit mycobacterial invasion using a flow-cytometry-based assay developed by Bermúdez and Goodman [ 39 ] and later modified by us [ 26 ]. In brief, A549 and U937 cells (1 × 10 6 ) seeded overnight on 6-well plates were incubated for 1 h with different peptide concentrations.…”

“…Specifically in the case of M. tuberculosis , our group has characterized and determined the binding profiles of three mycobacterial membrane proteins [ 23 - 25 ]. More recently, the biological relevance of HABPs derived from some other mycobacterial proteins has been demonstrated using a flow-cytometry-based assay to assess the capacity of HABPs to mycobacterial inhibit invasion of target cells [ 26 - 28 ].…”

The Mycobacterium tuberculosis membrane protein Rv0180c: Evaluation of peptide sequences implicated in mycobacterial invasion of two human cell lines

“…Surface proteins act both as interface and barriers between the bacteria and the host cell, thus they have become subjects of intense research [15]. Bearing this in mind, our group has determined the presence, transcription and expression of five M. tuberculosis membrane proteins: Rv2004c, Rv2536, Rv1510c, Rv2560, Rv2707, Rv1980c and Rv0679c [12,18,26,29,53,58,70]. In addition, the binding profiles of each of these proteins to A549 and U937 cell lines has been determined by means of binding assays with non-overlapping synthetic peptides spanning the entire length of each protein.…”