The Roles of Molecular Chaperones in the Bacterial Cell

  • Peter A. Lund
Conference paper
Part of the NATO ASI Series book series (volume 103)


In this chapter, I shall look at the major bacterial molecular chaperones, and summarise the evidence for what we know about their cellular role. Molecular chaperones have risen from obscurity to near superstar status in the last few years, as we have learned that many fundamental aspects of protein function in all cells require the help of other proteins in order to take place. These include the correct folding of proteins as they are translated, their delivery to and passage across membranes, and the repair of proteins which have become inactive because of exposure of the cells to stresses such as an increase in temperature. “Molecular chaperone” is the generic name given to a protein that assists in these processes. The review will be from the point of what is known about what these proteins do in the cell, although I will also describe what is currently understood about the mechanisms by which some of the chaperones work, and how their diverse functions can sometimes be understood in terms of a single mechanism. Finally, I will try to summarise some of the areas where I think key questions about the cellular role of molecular chaperones remain unanswered.


Molecular Chaperone Trigger Factor Hydrophobic Side Chain Cellular Role GroEL Protein 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Allen SP, Polazzi JO, Gierse JK, Easton AM (1992) Two novel heat shock proteins produced in response to heterologous protein expression in Escherichia coli. J Bacteriol 174, 6938–6947PubMedGoogle Scholar
  2. Bardwell JCA, Craig EA (1988) Ancient heat-shock gene is dispensable. J Bacteriol 170, 2977–2983.PubMedGoogle Scholar
  3. Braig K. Otkinowski Z, Hegde R, Boisvert DC, Joachimiak A, Horwich AL, Sigler PB (1994) The crystal structure of the bacterial chaperonin GroEL at 2.8-angstrom. Nature 371, 578–586.PubMedCrossRefGoogle Scholar
  4. Buchberger A, Schroder H, Hesterkamp T, Schonfeld HJ, Bukau B (1996) Substrate shuttling between the DnaK and GroEL systems indicates a chaperone network promoting protein folding. J Mol Biol 261, 328–333PubMedCrossRefGoogle Scholar
  5. Bukau B, Walker GC (1989) A-dnaK52 mutants of Escherichia coli have defects in chromosome segregation and plasmid maintenance at normal growth temperatures. J Bacteriol 171, 6030–6038PubMedGoogle Scholar
  6. Ellis RI (1994) Molecular chaperones–opening and closing the Anfinsen cage. Current Biol 4, 633–635CrossRefGoogle Scholar
  7. Ensgraber M, Loos M (1992) A 66kDa heat shock protein of Salmonella typhimurium is responsible for binding of the bacterium to intestinal mucus. Infect Immun 60, 3072–3078PubMedGoogle Scholar
  8. Fischer HM, Babst M, Kaspar T, Acuna G, Arigoni F, Hennecke H. (1993) One member of a groESL-like chaperonin multigene family in Bradyrhizobium japonicum is coregulated with symbiotic nitrogen fixation genes. EMBO Jou 12, 2901–2912Google Scholar
  9. Franetic O, Kumamoto C (1996) Escherichia coli SecB stimulates export without maintaining export competence of ribose-binding protein signal sequence mutants. J Bacteriol 178, 5954–5959Google Scholar
  10. Gaitanaris GA, Vysokanov A, Hung SC, Gottesman ME, Gragerov A (1994) Successive action of Escherichia coli chaperones in vivo Mol Micro 14, 861–869CrossRefGoogle Scholar
  11. Georgellis D, Sohlberg B, Hartl FU. Von Gabain A (1995) Identification of GroEL as a constituent of an mRNA protection complex in Escherichia coli. Mol Micro 16, 1259–1268CrossRefGoogle Scholar
  12. Goloubinoff P, Gatenby AA, Lorimer G (1989) GroE heat shock proteins promote assembly of foreign ribulose bisphosphate oligomers in Escherichia coli. Nature 337, 44–17PubMedCrossRefGoogle Scholar
  13. Gragerov A, Nudler E. Komissarova N, Gaitanaris GA, Nikiforov V (1992) Co-operation of GroEL/GroES and DnaK/DnaJ heat shock proteins in preventing protein misfolding in Escherichia coli. Proc Natl Acad Sci USA 89, 10341–10344PubMedCrossRefGoogle Scholar
  14. Guthrie B, Widmer W (1990) Trigger factor depletion or over-production causes defective cell division but does not block protein export. J Bacteriol 172, 5555–5562PubMedGoogle Scholar
  15. Hartl FU (1996) Molecular chaperones in cellular protein folding. Nature 381, 571–580PubMedCrossRefGoogle Scholar
  16. Hesterkamp T, Hauser S. Lutcke H. Bukau B (1996) Escherichia coli trigger factor is a prolyl isomerase that associates with nascent polypeptide chains. Proc Natl Acad Sci USA 93, 4437–4441CrossRefGoogle Scholar
  17. Honvich AL, Low KB. Fenton WA. Hirshfield IN. Furtak K (1993) Folding in vivo of bacterial cytoplasmic proteins: role of GroEL. Cell 74, 909–917CrossRefGoogle Scholar
  18. Ivic A. Olden D, Wallington EJ, Lund PA (1997) The groEL deletion of Escherichia coli is complemented by a Rhizobium leguntinosarum groEL homologue at 37oC but not at 43oC. Gene, in press.Google Scholar
  19. Jakob U. Gaestel M. Engel K. Buchner J. (1994) Small heat shock proteins are molecular chaperones. J Biol Chem 268. 1517–1520Google Scholar
  20. Kandror O, Sherman M, Moerschell R Goldberg (1997) Trigger factor associates FFith GroEL in vivo and promotes its binding to certain poly-peptides. J Biol Chem 272, 1730–1734PubMedCrossRefGoogle Scholar
  21. Kanemori M, Mori H. Yura T. (1994) Effects of reduced levels of GroE chaperones on protein metabolism: enhanced synthesis of heat-shock proteins during steady state growth. J bacteriol 176, 4235–4242.PubMedGoogle Scholar
  22. Kumamoto CA and Beckwith J (1985) Evidence for specificity at an early step in protein export in Escherichia coli. J Bacteriol 163. 267–274PubMedGoogle Scholar
  23. Kusukawa N, Yura T (1988) Heat shock protein GroE of Escherichia coli: key protective roles against thermal stress. Genes Dev 2, 874–882PubMedCrossRefGoogle Scholar
  24. Kusukawa N, Yura T, Ueguchi C, Akiyama Y. Ito K (1989) Effects of mutations in the heat shock genes groES and groEL on protein export of Escherichia coli. EMBO Jou 8, 3517–3521Google Scholar
  25. Lecker S, Lill R Ziegelhoffer T, Georgopoulos C, Bassford PJ, Kumamoto CA, Wickner W (1989) Three pure chaperone proteins of Escherichia coli-secB, trigger factor, and GroEL–form soluble complexes with precursor proteins in vitro. EMBO Jou 8, 2703–2709Google Scholar
  26. Lorimer GH. (1996) A quantitative assessment of the role of chaperonin proteins in protein folding in vivo. FASEB Jou 10, 5–9Google Scholar
  27. Martin J, Horwich AL, Hartl F-U. (1992) Prevention of protein denaturation under heat stress by the chaperonin Hsp60. Science 258. 995–998PubMedCrossRefGoogle Scholar
  28. Phillips GJ, Silhavy TJ (1990) heat-shock proteins DnaK and GroEL facilitate protein export of LacZhybrid proteins in Escherichia coli. Nature 344, 882–884PubMedCrossRefGoogle Scholar
  29. Randall LL, Hardy SJS (1995) High selectivity with low specificity: how SecB has solved the paradox of chaperone binding. Trends Biochem Sci 20, 65–69PubMedCrossRefGoogle Scholar
  30. Schroder H, Langer T. Hartl F-U, Bukau B (1993) DnaK, DnaJ and GrpE form a cellular chaperone machinery capable of repairing heat-induced protein damage. EMBO Jou 12, 4137–4144Google Scholar
  31. Skowyra D, McKenny K, Wickner SH (1995) Function of molecular chaperones in bacteriophage and plasmid DNA replication. Seminars Virol 6, 43–51CrossRefGoogle Scholar
  32. Straus D. Walter W, Gross CA (1990) DnaK DnaJ and GrpE heat-shock proteins negatively regulate heat-shock gene expression by controlling the synthesis and stability of sigma-32. Genes Devel 4, 2202–2209PubMedCrossRefGoogle Scholar
  33. Thomas JG, Baneyx F (1996) protein folding in the cytoplasm of Escherichia coli: requirements for the DnaK-DnaJ-GrpE and GroEL-GroES molecular chaperone machines. Mol Micro 21, 1185–1196CrossRefGoogle Scholar
  34. Ueguchi C, Kakeda M, Yamada H, Mizuno T (1994) An analogue of the DnaJ molecular chaperone in Escherichia coli. Proc Nati Acad Sci USA 6, 1165–1172.Google Scholar
  35. Van Dyk TK, Gatenby AA, laRossa RA (1989) Demonstration by genetic suppression of interaction of GroE products with many proteins. Nature 342, 451–453.PubMedCrossRefGoogle Scholar
  36. Wawrzynow A, Wojtkowiak D, Marszalek J, Banecki B, Jonsen M, Graves B, Goergopoulos C, Zylicz M (1995) The C1pX heat shock protein of Escherichia coli, the ATP-dependent substrate specificity component of the CIpP-CIpX complex, is a novel molecular chaperone EMBO Jou 14, 1867–1877Google Scholar
  37. Wickner S. Gottesman S, Skowyra D, Hoskins J. McKenny K, Maurizi MR (1994) A molecular chaperone. CIpA, functions like DnaK and DnaJ. Proc Natl Acad Sci USA 91, 12218–12222PubMedCrossRefGoogle Scholar
  38. Wild J, Altman E. Yura T and Gross CA (1992) DnaK and DnaJ heat-shock proteins participate in protein export in Escherichia coli. Genes Devel 6, 1165–1172PubMedCrossRefGoogle Scholar
  39. Wild J. Rossmeissl P. Walter WA and Gross CA (1996) Involvement of the DnaK-DnaJ-GrpE chaperone team in protein secretion in Escherichia coli. J Bacteriol 178. 3608–3613PubMedGoogle Scholar
  40. Zeiistra-Ryalls J, Fayet O. Georgopoulos C (1991) The universally conserved GroE (Hsp60) chaperonins. Annu Rev Microbiol 45. 301–325CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 1998

Authors and Affiliations

  • Peter A. Lund
    • 1
  1. 1.School of Biological SciencesUniversity of BirminghamBirminghamUK

Personalised recommendations