Genetic analysis of superoxide dismutase, the 23 kilodalton antigen of Mycobacterium tuberculosis

Mol Microbiol. 1991 Feb;5(2):381-91. doi: 10.1111/j.1365-2958.1991.tb02120.x.


The gene encoding a 23 kilodalton protein antigen has been cloned from Mycobacterium tuberculosis by screening of a recombinant DNA library with monoclonal antibodies. The product of the gene has been identified as the superoxide dismutase (SOD) of M. tuberculosis on the basis of sequence comparison and by expression of the recombinant protein in a functionally active form. The derived amino acid sequence of M. tuberculosis SOD reveals a close similarity to manganese-containing SODs from other organisms, in spite of the fact that previous studies using the purified enzyme have identified iron as the preferred metal ion ligand. SOD is present in the extracellular fluid of logarithmic-phase cultures of M. tuberculosis, but the structural gene is not preceded by a signal peptide sequence. Insertion of the M. tuberculosis SOD gene into a novel shuttle vector demonstrated the mycobacteria but is ineffective in Escherichia coli.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Antigens, Bacterial / genetics*
  • Base Sequence
  • Blotting, Western
  • Cloning, Molecular
  • DNA, Bacterial
  • Electrophoresis, Polyacrylamide Gel
  • Genetic Vectors
  • Immunoassay
  • Molecular Sequence Data
  • Mycobacterium tuberculosis / enzymology
  • Mycobacterium tuberculosis / genetics*
  • Mycobacterium tuberculosis / immunology
  • Recombinant Proteins / genetics
  • Recombinant Proteins / immunology
  • Recombinant Proteins / metabolism
  • Restriction Mapping
  • Sequence Homology, Nucleic Acid
  • Superoxide Dismutase / genetics*
  • Superoxide Dismutase / immunology
  • Superoxide Dismutase / metabolism


  • Antigens, Bacterial
  • DNA, Bacterial
  • Recombinant Proteins
  • Superoxide Dismutase

Associated data

  • GENBANK/X52861