Characterization of the gene encoding the MPB51, one of the major secreted protein antigens of Mycobacterium bovis BCG, and identification of the secreted protein closely related to the fibronectin binding 85 complex

Scand J Immunol. 1995 May;41(5):433-42. doi: 10.1111/j.1365-3083.1995.tb03589.x.


The secreted protein MPB51 is one of the major proteins in the culture filtrate of Mycobacterium bovis BCG (BCG) and is a protein immunologically cross-reacting with the fibronectin binding 85 complex secreted by this bacterium. The gene encoding MPB51 (mpb51) was cloned, sequenced, and expressed in Escherichia coli. The mpb51 gene was mapped downstream of the gene for 85A component with 179 bp spaces. The mpb51 gene encoded 299 amino acids, including 33 amino acids for the signal peptide, followed by 266 amino acids for the mature protein with a molecular mass of 27807.37 Da. This is the first complete sequence of MPB51. MPB51 showed 37-43% homology to the components of 85 complex. Two-dimensional electrophoresis of culture fluids of BCG and Western blotting indicated the existence of the other novel protein(s) which strongly cross-reacted with the alpha antigen (85B) and MPB51.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Amino Acid Sequence
  • Antigens, Bacterial / chemistry*
  • Antigens, Bacterial / genetics*
  • Antigens, Bacterial / immunology
  • Bacterial Proteins*
  • Base Sequence
  • Cloning, Molecular
  • Cross Reactions
  • Escherichia coli / genetics
  • Genes, Bacterial*
  • Molecular Sequence Data
  • Mycobacterium bovis / genetics
  • Mycobacterium bovis / immunology*
  • Recombinant Proteins / biosynthesis
  • Sequence Homology, Amino Acid


  • Antigens, Bacterial
  • Bacterial Proteins
  • MPT51 protein, Mycobacterium
  • Recombinant Proteins
  • antigen 85, Mycobacterium bovis

Associated data

  • GENBANK/D26486