A novel mycobacterial antigen relevant to cellular immunity belongs to a family of secreted lipoproteins

Scand J Immunol. 1997 Nov;46(5):445-51. doi: 10.1046/j.1365-3083.1997.d01-150.x.

Abstract

The gene sequence of a novel 24.1 kDa Mycobacterium tuberculosis protein was identified within the Sanger Centre (UK) M. tuberculosis genome database (cosmid MTCY24G1) by searching with a 126 bp DNA sequence isolated from a genomic M. leprae lambda gt11 library with M. leprae reactive human T cell clones as probes. The 24.1 kDa antigen is common to the vaccine strain Mycobacterium bovis BCG, as well as Mycobacterium leprae. The 699 bp open reading frame encodes a 233 amino acid long precursor protein with a signal peptide sequence for secretion and a consensus motif for lipid conjugation, which suggests that the mature protein is an exported lipoprotein antigen. The molecular mass of the mature protein antigen from M. leprae sonicate was shown to correspond to the deduced size of the M. tuberculosis protein by T cell Western analysis. Homology searches revealed two other similarly sized hypothetical secreted mycobacterial lipoproteins within the M. tuberculosis genome database.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Bacterial Proteins / classification
  • Bacterial Proteins / genetics
  • Bacterial Proteins / immunology*
  • Bacterial Proteins / metabolism
  • Base Sequence
  • CD4-Positive T-Lymphocytes / immunology
  • Clone Cells
  • Consensus Sequence
  • DNA, Bacterial / genetics
  • Epitopes / genetics
  • Epitopes / immunology
  • Gene Library
  • Genes, Bacterial
  • Humans
  • Immunity, Cellular
  • Molecular Sequence Data
  • Molecular Weight
  • Multigene Family*
  • Mycobacterium bovis / genetics
  • Mycobacterium bovis / immunology
  • Mycobacterium leprae / genetics
  • Mycobacterium leprae / immunology
  • Mycobacterium tuberculosis / genetics
  • Mycobacterium tuberculosis / immunology*
  • Open Reading Frames
  • Sequence Alignment
  • Sequence Homology, Nucleic Acid
  • Species Specificity

Substances

  • Bacterial Proteins
  • DNA, Bacterial
  • Epitopes
  • antigen 24.1-kDa, Mycobacterium tuberculosis