Primary structure of a human mitochondrial protein homologous to the bacterial and plant chaperonins and to the 65-kilodalton mycobacterial antigen

Mol Cell Biol. 1989 May;9(5):2279-83. doi: 10.1128/mcb.9.5.2279-2283.1989.


The complete cDNA for a human mitochondrial protein designated P1, which was previously identified as a microtubule-related protein, has been cloned and sequenced. The deduced amino acid sequence of P1 shows strong homology (40 to 50% identical residues and an additional 20% conservative replacements) to the 65-kilodalton major antigen of mycobacteria, to the GroEL protein of Escherichia coli, and to the ribulose 1,5-bisphosphate carboxylase-oxygenase (rubisco) subunit binding protein of plant chloroplasts. Similar to the case with the latter two proteins, which have been shown to act as chaperonins in the posttranslational assembly of oligomeric protein structures, it is suggested that P1 may play a similar role in mammalian cells. The observed high degree of homology between human P1 and mycobacterial antigen also suggests the possible involvement of this protein in certain autoimmune diseases.

Publication types

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

MeSH terms

  • Amino Acid Sequence
  • Antigens, Bacterial / genetics
  • Bacteria / genetics
  • Bacterial Proteins / genetics*
  • Base Sequence
  • Chaperonin 60
  • Chaperonins
  • DNA / genetics
  • Heat-Shock Proteins / genetics*
  • Humans
  • Microtubule-Associated Proteins / genetics*
  • Mitochondrial Proteins
  • Molecular Sequence Data
  • Mycobacterium / genetics
  • Plant Proteins / genetics*
  • Plants / genetics*


  • Antigens, Bacterial
  • Bacterial Proteins
  • Chaperonin 60
  • HSPD1 protein, human
  • Heat-Shock Proteins
  • Microtubule-Associated Proteins
  • Mitochondrial Proteins
  • Plant Proteins
  • DNA
  • Chaperonins