Skip to main content
PMC home page
Journal of Bacteriology logoLink to Journal of Bacteriology
. 1996 Feb;178(4):1088–1093. doi: 10.1128/jb.178.4.1088-1093.1996

hrcA, the first gene of the Bacillus subtilis dnaK operon encodes a negative regulator of class I heat shock genes.

A Schulz 1, W Schumann 1
PMCID: PMC177769  PMID: 8576042

Abstract

Whereas in Escherichia coli only one heat shock regulon is transiently induced by mild heat stress, for Bacillus subtilis three classes of heat shock genes regulated by different mechanisms have been described. Regulation of class I heat shock genes (dnaK and groE operons) involves an inverted repeat (CIRCE element) which most probably serves as an operator for a repressor. Here, we report on the analyses of an hrcA null mutant (delta hrcA), in which hrcA, the first gene of the dnaK operon, was deleted from the B. subtilis chromosome. This strain was perfectly viable at low and high temperatures. Transcriptional analysis of the deletion mutant revealed a high level of constitutive expression of both the dnaK and groE operons even at a low temperature. A further increase in the amount of groE transcript was observed after temperature upshift, suggesting a second induction mechanism for this operon. Overproduction of HrcA protein from a second copy of hrcA derived from a plasmid (phrcA+) in B. subtilis wild-type and delta hrcA strains prevented heat shock induction of the dnaK and groE operons at the level of transcription almost completely and strongly reduced the amounts of mRNA at a low temperature as well. Whereas the wild-type strain needed 4 h to resume growth after temperature upshift, the delta hrcA strain stopped growth only for about 1 h. Overproduction of HrcA protein prior to a heat shock almost completely prevented growth at a high temperature. These data clearly demonstrate that the hrcA product serves as a negative regulator of class I heat shock genes.

Full Text

The Full Text of this article is available as a PDF (329.5 KB).

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Barbosa M. F., Yomano L. P., Ingram L. O. Cloning, sequencing and expression of stress genes from the ethanol-producing bacterium Zymomonas mobilis: the groESL operon. Gene. 1994 Oct 11;148(1):51–57. doi: 10.1016/0378-1119(94)90232-1. [DOI] [PubMed] [Google Scholar]
  2. Behrens S., Narberhaus F., Bahl H. Cloning, nucleotide sequence and structural analysis of the Clostridium acetobutylicum dnaJ gene. FEMS Microbiol Lett. 1993 Nov 15;114(1):53–60. doi: 10.1016/0378-1097(93)90141-n. [DOI] [PubMed] [Google Scholar]
  3. Bukau B. Regulation of the Escherichia coli heat-shock response. Mol Microbiol. 1993 Aug;9(4):671–680. doi: 10.1111/j.1365-2958.1993.tb01727.x. [DOI] [PubMed] [Google Scholar]
  4. Chang B. Y., Chen K. Y., Wen Y. D., Liao C. T. The response of a Bacillus subtilis temperature-sensitive sigA mutant to heat stress. J Bacteriol. 1994 Jun;176(11):3102–3110. doi: 10.1128/jb.176.11.3102-3110.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Deuerling E., Paeslack B., Schumann W. The ftsH gene of Bacillus subtilis is transiently induced after osmotic and temperature upshift. J Bacteriol. 1995 Jul;177(14):4105–4112. doi: 10.1128/jb.177.14.4105-4112.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Eaton T., Shearman C., Gasson M. Cloning and sequence analysis of the dnaK gene region of Lactococcus lactis subsp. lactis. J Gen Microbiol. 1993 Dec;139(12):3253–3264. doi: 10.1099/00221287-139-12-3253. [DOI] [PubMed] [Google Scholar]
  7. Gething M. J., Sambrook J. Protein folding in the cell. Nature. 1992 Jan 2;355(6355):33–45. doi: 10.1038/355033a0. [DOI] [PubMed] [Google Scholar]
  8. Hanahan D. Studies on transformation of Escherichia coli with plasmids. J Mol Biol. 1983 Jun 5;166(4):557–580. doi: 10.1016/s0022-2836(83)80284-8. [DOI] [PubMed] [Google Scholar]
  9. Itaya M., Tanaka T. Gene-directed mutagenesis on the chromosome of Bacillus subtilis 168. Mol Gen Genet. 1990 Sep;223(2):268–272. doi: 10.1007/BF00265063. [DOI] [PubMed] [Google Scholar]
  10. Krüger E., Völker U., Hecker M. Stress induction of clpC in Bacillus subtilis and its involvement in stress tolerance. J Bacteriol. 1994 Jun;176(11):3360–3367. doi: 10.1128/jb.176.11.3360-3367.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Le Grice S. F. Regulated promoter for high-level expression of heterologous genes in Bacillus subtilis. Methods Enzymol. 1990;185:201–214. doi: 10.1016/0076-6879(90)85020-o. [DOI] [PubMed] [Google Scholar]
  12. Margolin W., Howe M. M. Localization and DNA sequence analysis of the C gene of bacteriophage Mu, the positive regulator of Mu late transcription. Nucleic Acids Res. 1986 Jun 25;14(12):4881–4897. doi: 10.1093/nar/14.12.4881. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Merrill D., Hartley T. F., Claman H. N. Electroimmunodiffusion (EID): a simple, rapid method for quantitation of immunoglobulins in dilute biological fluids. J Lab Clin Med. 1967 Jan;69(1):151–159. [PubMed] [Google Scholar]
  14. Ohta T., Saito K., Kuroda M., Honda K., Hirata H., Hayashi H. Molecular cloning of two new heat shock genes related to the hsp70 genes in Staphylococcus aureus. J Bacteriol. 1994 Aug;176(15):4779–4783. doi: 10.1128/jb.176.15.4779-4783.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  15. Riethdorf S., Völker U., Gerth U., Winkler A., Engelmann S., Hecker M. Cloning, nucleotide sequence, and expression of the Bacillus subtilis lon gene. J Bacteriol. 1994 Nov;176(21):6518–6527. doi: 10.1128/jb.176.21.6518-6527.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Sanger F., Nicklen S., Coulson A. R. DNA sequencing with chain-terminating inhibitors. Proc Natl Acad Sci U S A. 1977 Dec;74(12):5463–5467. doi: 10.1073/pnas.74.12.5463. [DOI] [PMC free article] [PubMed] [Google Scholar]
  17. Schmidt A., Schiesswohl M., Völker U., Hecker M., Schumann W. Cloning, sequencing, mapping, and transcriptional analysis of the groESL operon from Bacillus subtilis. J Bacteriol. 1992 Jun;174(12):3993–3999. doi: 10.1128/jb.174.12.3993-3999.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  18. Schmiel D. H., Wyrick P. B. Another putative heat-shock gene and aminoacyl-tRNA synthetase gene are located upstream from the grpE-like and dnaK-like genes in Chlamydia trachomatis. Gene. 1994 Jul 22;145(1):57–63. doi: 10.1016/0378-1119(94)90322-0. [DOI] [PubMed] [Google Scholar]
  19. Schulz A., Tzschaschel B., Schumann W. Isolation and analysis of mutants of the dnaK operon of Bacillus subtilis. Mol Microbiol. 1995 Feb;15(3):421–429. doi: 10.1111/j.1365-2958.1995.tb02256.x. [DOI] [PubMed] [Google Scholar]
  20. Segal G., Ron E. Z. Heat shock transcription of the groESL operon of Agrobacterium tumefaciens may involve a hairpin-loop structure. J Bacteriol. 1993 May;175(10):3083–3088. doi: 10.1128/jb.175.10.3083-3088.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  21. Vanet A., Plumbridge J. A., Alix J. H. Cotranscription of two genes necessary for ribosomal protein L11 methylation (prmA) and pantothenate transport (panF) in Escherichia coli K-12. J Bacteriol. 1993 Nov;175(22):7178–7188. doi: 10.1128/jb.175.22.7178-7188.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Vanet A., Plumbridge J. A., Guérin M. F., Alix J. H. Ribosomal protein methylation in Escherichia coli: the gene prmA, encoding the ribosomal protein L11 methyltransferase, is dispensable. Mol Microbiol. 1994 Dec;14(5):947–958. doi: 10.1111/j.1365-2958.1994.tb01330.x. [DOI] [PubMed] [Google Scholar]
  23. Wetzstein M., Völker U., Dedio J., Löbau S., Zuber U., Schiesswohl M., Herget C., Hecker M., Schumann W. Cloning, sequencing, and molecular analysis of the dnaK locus from Bacillus subtilis. J Bacteriol. 1992 May;174(10):3300–3310. doi: 10.1128/jb.174.10.3300-3310.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Yuan G., Wong S. L. Isolation and characterization of Bacillus subtilis groE regulatory mutants: evidence for orf39 in the dnaK operon as a repressor gene in regulating the expression of both groE and dnaK. J Bacteriol. 1995 Nov;177(22):6462–6468. doi: 10.1128/jb.177.22.6462-6468.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. Yura T., Nagai H., Mori H. Regulation of the heat-shock response in bacteria. Annu Rev Microbiol. 1993;47:321–350. doi: 10.1146/annurev.mi.47.100193.001541. [DOI] [PubMed] [Google Scholar]
  26. Zuber U., Schumann W. CIRCE, a novel heat shock element involved in regulation of heat shock operon dnaK of Bacillus subtilis. J Bacteriol. 1994 Mar;176(5):1359–1363. doi: 10.1128/jb.176.5.1359-1363.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Zuber U., Schumann W. Tn5cos: a transposon for restriction mapping of large plasmids using phage lambda terminase. Gene. 1991 Jul 15;103(1):69–72. doi: 10.1016/0378-1119(91)90392-o. [DOI] [PubMed] [Google Scholar]

Articles from Journal of Bacteriology are provided here courtesy of American Society for Microbiology (ASM)

RESOURCES