1887

Abstract

Natural competence for genetic transformation in is controlled by the ComCDE signal-transduction pathway. Together, ComD, a membrane histidine kinase, and ComE, its cognate response regulator, constitute a typical two-component regulatory system involved in sensing the -encoded competence-stimulating peptide (CSP). The operon is strongly upregulated when CSP reaches a critical threshold, probably to coordinate competence induction throughout the population. During a study of the early regulation of the operon, a mutation which resulted in increased -galactosidase production from a  : :  fusion was isolated. This mutation, which was characterized as a G→T change in the transcription terminator of the tRNA located immediately upstream of , is suggested to destabilize the terminator and to allow transcriptional readthrough of . Here, it is shown that, quite unexpectedly, the mutation confers reduced transformability. A series of experiments undertaken with the aim of understanding this surprising phenotype is described. Evidence is presented that increased basal-level expression of impedes both spontaneous and CSP-induced competence in . There is a discussion of how an increased concentration of ComD and/or ComE could affect competence development.

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2006-02-01
2020-04-01
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References

  1. Alloing G, Granadel C, Morrison D. A, Claverys J. P. 1996; Competence pheromone, oligopeptide permease and induction of competence in Streptococcus pneumoniae . Mol Microbiol21:471–478[CrossRef]
    [Google Scholar]
  2. Alloing G, Martin B, Granadel C, Claverys J. P. 1998; Development of competence in Streptococcus pneumoniae : pheromone auto-induction and control of quorum-sensing by the oligopeptide permease. Mol Microbiol29:75–84[CrossRef]
    [Google Scholar]
  3. Bergé M, Moscoso M, Prudhomme M, Martin B., Claverys J. P. 2002; Uptake of transforming DNA in Gram-positive bacteria: a view from Streptococcus pneumoniae . Mol Microbiol45:411–421[CrossRef]
    [Google Scholar]
  4. Chastanet A, Prudhomme M, Claverys J. P, Msadek T. 2001; Regulation of Streptococcus pneumoniae clp genes and their role in competence development and stress survival. J Bacteriol183:7295–7307[CrossRef]
    [Google Scholar]
  5. Chen J. D, Morrison D. A. 1987; Modulation of competence for genetic transformation in Streptococcus pneumoniae . J Gen Microbiol133:1959–1967
    [Google Scholar]
  6. Claverys J. P, Håvarstein L. S. 2002; Extra-cellular peptide control of competence for genetic transformation in Streptococcus pneumoniae . Front Biosci7:1798–1814[CrossRef]
    [Google Scholar]
  7. Dagkessamanskaia A, Moscoso M, Overweg K, Reuter M, Martin B, Wells J, Claverys J. P, Hénard V, Guiral S. 2004; Interconnection of competence, stress and CiaR regulons in Streptococcus pneumoniae : competence triggers stationary phase autolysis of ciaR mutant cells. Mol Microbiol51:1071–1086[CrossRef]
    [Google Scholar]
  8. Guiral S. 2004; Libération de pneumolysine lors de la compétence pour la transformation génétique de la bactérie Streptococcus pneumoniae: implication d'une bactériocine à deux peptides PhD dissertation Université Paul Sabatier;
    [Google Scholar]
  9. Guiral S, Mitchell T. J, Martin B, Claverys J. P. 2005; Competence-programmed predation of noncompetent cells in the human pathogen Streptococcus pneumoniae : genetic requirements. Proc Natl Acad Sci U S A102:8710–8715[CrossRef]
    [Google Scholar]
  10. Guiral S, Dagkessamanskaia A, Moscoso M, Claverys J. P. 2006a; Competence in Streptococcus pneumoniae : what is it for?. In The Molecular Biology of Streptococci Edited by Hakenbeck R., Chhatwal G. S.. Norwich, UK: Horizon Scientific Press;
    [Google Scholar]
  11. Guiral S, Granadel C, Prudhomme M, Martin B, Claverys J. P, Hénard V, Laaberki M.-H. 2006b; Construction and evaluation of a chromosomal expression platform (CEP) for ectopic, maltose-driven gene expression in Streptococcus pneumoniae . Microbiology152:343–349[CrossRef]
    [Google Scholar]
  12. Håvarstein L. S, Coomaraswamy G., Morrison D. A. 1995; An unmodified heptadecapeptide pheromone induces competence for genetic transformation in Streptococcus pneumoniae . Proc Natl Acad Sci U S A92:11140–11144[CrossRef]
    [Google Scholar]
  13. Hui F. M, Morrison D. A. 1991; Genetic transformation in Streptococcus pneumoniae : nucleotide sequence analysis shows comA , a gene required for competence induction, to be a member of the bacterial ATP-dependent transport protein family. J Bacteriol173:372–381
    [Google Scholar]
  14. Hui F. M, Zhou L, Morrison D. A. 1995; Competence for genetic transformation in Streptococcus pneumoniae : organization of a regulatory locus with homology to two lactococcin A secretion genes. Gene153:25–31[CrossRef]
    [Google Scholar]
  15. Lee M. S, Morrison D. A. 1999; Identification of a new regulator in Streptococcus pneumoniae linking quorum sensing to competence for genetic transformation. J Bacteriol181:5004–5016
    [Google Scholar]
  16. Luo P, Li H, Morrison D. A. 2004; Identification of ComW as a new component in the regulation of genetic transformation in Streptococcus pneumoniae . Mol Microbiol54:172–183[CrossRef]
    [Google Scholar]
  17. Martin B, Prats H, Claverys J. P. 1985; Cloning of the hexA mismatch repair of Streptococcus pneumoniae and identification of the product. Gene34:293–303[CrossRef]
    [Google Scholar]
  18. Martin B, García P, Castanié M. P, Claverys J. P. 1995; The recA gene of Streptococcus pneumoniae is part of a competence-induced operon and controls lysogenic induction. Mol Microbiol15:367–379[CrossRef]
    [Google Scholar]
  19. Martin B, Prudhomme M, Alloing G, Granadel C, Claverys J. P. 2000; Cross-regulation of competence pheromone production and export in the early control of transformation in Streptococcus pneumoniae . Mol Microbiol38:867–878[CrossRef]
    [Google Scholar]
  20. Mortier-Barrière I, de Saizieu A, Claverys J. P, Martin B. 1998; Competence-specific induction of recA is required for full recombination proficiency during transformation in Streptococcus pneumoniae . Mol Microbiol27:159–170[CrossRef]
    [Google Scholar]
  21. Pestova E. V, Håvarstein L. S, Morrison D. A. 1996; Regulation of competence for genetic transformation in Streptococcus pneumoniae by an auto-induced peptide pheromone and a two-component regulatory system. Mol Microbiol21:853–864[CrossRef]
    [Google Scholar]
  22. Peterson S, Sung C. K, Cline R.13 other authors 2004; Identification of competence pheromone responsive genes in Streptococcus pneumoniae . Mol Microbiol51:1051–1070[CrossRef]
    [Google Scholar]
  23. Prudhomme M, Claverys J. P. 2006; There will be a light: the use of luc transcriptional fusions in living pneumococcal cells. In The Molecular Biology of Streptococci Edited by Hakenbeck R., Chhatwal G. S.. Norwich, UK: Horizon Scientific Press;
    [Google Scholar]
  24. Sambrook J, Fritsch E. F, Maniatis T. 1989; Molecular Cloning: a Laboratory Manual, 2nd edn.. Cold Spring Harbor, NY: Cold Spring Harbor Laboratory;
    [Google Scholar]
  25. Sung C. K, Morrison D. A. 2005; Two distinct functions of ComW in stabilization and activation of the alternative sigma factor ComX in Streptococcus pneumoniae . J Bacteriol187:3052–3061[CrossRef]
    [Google Scholar]
  26. Sung C. K, Li H, Claverys J. P, Morrison D. A. 2001; An rpsL cassette, janus, for gene replacement through negative selection in Streptococcus pneumoniae . Appl Environ Microbiol67:5190–5196[CrossRef]
    [Google Scholar]
  27. Surette M. G, Levit M, Liu Y, Lukat G, Ninfa E. G, Ninfa A, Stock J. B. 1996; Dimerization is required for the activity of the protein histidine kinase CheA that mediates signal transduction in bacterial chemotaxis. J Biol Chem271:939–945[CrossRef]
    [Google Scholar]
  28. Ween O, Gaustad P, Håvarstein L. S. 1999; Identification of DNA binding sites for ComE, a key regulator of natural competence in Streptococcus pneumoniae . Mol Microbiol33:817–827[CrossRef]
    [Google Scholar]
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