1887

Abstract

Many Gram-positive and Gram-negative bacteria possess natural competence mechanisms for DNA capture and internalization. In , natural competence is absolutely dependent upon the presence of a seven-gene operon known as the operon (). In species of , this function has been described for a four-gene operon ( in and in ). In this study, a nine- operon (named ) required for natural competence in was identified and characterized. Orf analysis of this operon indicates that the first four Orfs (ComYA–D) share strong homology with ComYA–D of and CglA–D of , the fifth to seventh Orfs (ComYE–G) match conserved hypothetical proteins from various species of with ComYF possessing a predicted ComGF domain, the eighth Orf (ComYH) shows a strong homology to numerous DNA methyltransferases from restriction/modification systems, and the ninth Orf (ComYI) is homologous to acetate kinase (AckA). RT-PCR analysis of the junctions confirmed that all nine s were present in a single transcript, while real-time RT-PCR analysis demonstrated that these s were expressed at a level very similar to that of the first in the operon. Mutations were constructed in all nine putative s. The first seven genes () were found to be essential for natural competence, while and had reduced and normal natural competence ability, respectively. Analyses of –luciferase reporter fusions indicated that expression is growth-phase dependent, with maximal expression at an OD of about 0·2, while mutations in , and reduced the level of expression. In addition, operon expression appears to be correlated with natural competence ability.

Loading

Article metrics loading...

/content/journal/micro/10.1099/mic.0.27554-0
2005-01-01
2019-10-16
Loading full text...

Full text loading...

/deliver/fulltext/micro/151/1/mic1510157.html?itemId=/content/journal/micro/10.1099/mic.0.27554-0&mimeType=html&fmt=ahah

References

  1. Ajdić, D., McShan, W. M., McLaughlin, R. E. & 16 other authors ( 2002; ). Genome sequence of Streptococcus mutans UA159, a cariogenic dental pathogen. Proc Natl Acad Sci U S A 99, 14434–14439.[CrossRef]
    [Google Scholar]
  2. Califano, J. V., Arimoto, T. & Kitten, T. ( 2003; ). The genetic relatedness of Porphyromonas gingivalis clinical and laboratory strains assessed by analysis of insertion sequence (IS) element distribution. J Periodontal Res 38, 411–416.[CrossRef]
    [Google Scholar]
  3. Chen, P., Qi, F., Novak, J. & Caufield, P. W. ( 1999; ). The specific genes for lantibiotic mutacin II biosynthesis in Streptococcus mutans T8 are clustered and can be transferred en bloc. Appl Environ Microbiol 65, 1356–1360.
    [Google Scholar]
  4. Cheng, Q., Campbell, E. A., Naughton, A. M., Johnson, S. & Masure, H. R. ( 1997; ). The com locus controls genetic transformation in Streptococcus pneumoniae. Mol Microbiol 23, 683–692.[CrossRef]
    [Google Scholar]
  5. Chung, Y. S. & Dubnau, D. ( 1998; ). All seven comG open reading frames are required for DNA binding during transformation of competent Bacillus subtilis. J Bacteriol 180, 41–45.
    [Google Scholar]
  6. Chung, Y. S., Breidt, F. & Dubnau, D. ( 1998; ). Cell surface localization and processing of the ComG proteins, required for DNA binding during transformation of Bacillus subtilis. Mol Microbiol 29, 905–913.[CrossRef]
    [Google Scholar]
  7. Claverys, J. P. & Martin, B. ( 2003; ). Bacterial “competence” genes: signatures of active transformation, or only remnants? Trends Microbiol 11, 161–165.[CrossRef]
    [Google Scholar]
  8. Cvitkovitch, D. G. ( 2001; ). Genetic competence and transformation in oral streptococci. Crit Rev Oral Biol Med 12, 217–243.[CrossRef]
    [Google Scholar]
  9. Dubnau, D. ( 1999; ). DNA uptake in bacteria. Annu Rev Microbiol 53, 217–244.[CrossRef]
    [Google Scholar]
  10. Ghigo, J. M. ( 2001; ). Natural conjugative plasmids induce bacterial biofilm development. Nature 412, 442–445.[CrossRef]
    [Google Scholar]
  11. Grundy, F. J., Waters, D. A., Allen, S. H. & Henkin, T. M. ( 1993; ). Regulation of the Bacillus subtilis acetate kinase gene by CcpA. J Bacteriol 175, 7348–7355.
    [Google Scholar]
  12. Hanahan, D. ( 1983; ). Studies on transformation of Escherichia coli with plasmids. J Mol Biol 166, 557–580.[CrossRef]
    [Google Scholar]
  13. Hausner, M. & Wuertz, S. ( 1999; ). High rates of conjugation in bacterial biofilms as determined by quantitative in situ analysis. Appl Environ Microbiol 65, 3710–3713.
    [Google Scholar]
  14. Havarstein, L. S., Gaustad, P., Nes, I. F. & Morrison, D. A. ( 1996; ). Identification of the streptococcal competence-pheromone receptor. Mol Microbiol 21, 863–869.[CrossRef]
    [Google Scholar]
  15. Hendrickx, L., Hausner, M. & Wuertz, S. ( 2003; ). Natural genetic transformation in monoculture Acinetobacter sp. strain BD413 biofilms. Appl Environ Microbiol 69, 1721–1727.[CrossRef]
    [Google Scholar]
  16. Kapatral, V., Anderson, I., Ivanova, N. & 22 other authors ( 2002; ). Genome sequence and analysis of the oral bacterium Fusobacterium nucleatum strain ATCC 25586. J Bacteriol 184, 2005–2018.[CrossRef]
    [Google Scholar]
  17. Lee, M. S. & Morrison, D. A. ( 1999; ). Identification of a new regulator in Streptococcus pneumoniae linking quorum sensing to competence for genetic transformation. J Bacteriol 181, 5004–5016.
    [Google Scholar]
  18. Li, Y. H., Lau, P. C., Lee, J. H., Ellen, R. P. & Cvitkovitch, D. G. ( 2001; ). Natural genetic transformation of Streptococcus mutans growing in biofilms. J Bacteriol 183, 897–908.[CrossRef]
    [Google Scholar]
  19. Li, Y. H., Tang, N., Aspiras, M. B., Lau, P. C., Lee, J. H., Ellen, R. P. & Cvitkovitch, D. G. ( 2002; ). A quorum-sensing signaling system essential for genetic competence in Streptococcus mutans is involved in biofilm formation. J Bacteriol 184, 2699–2708.[CrossRef]
    [Google Scholar]
  20. Licht, T. R., Christensen, B. B., Krogfelt, K. A. & Molin, S. ( 1999; ). Plasmid transfer in the animal intestine and other dynamic bacterial populations: the role of community structure and environment. Microbiology 145, 2615–2622.
    [Google Scholar]
  21. Loimaranta, V., Tenovuo, J., Koivisto, L. & Karp, M. ( 1998; ). Generation of bioluminescent Streptococcus mutans and its usage in rapid analysis of the efficacy of antimicrobial compounds. Antimicrob Agents Chemother 42, 1906–1910.
    [Google Scholar]
  22. Loo, C. Y., Corliss, D. A. & Ganeshkumar, N. ( 2000; ). Streptococcus gordonii biofilm formation: identification of genes that code for biofilm phenotypes. J Bacteriol 182, 1374–1382.[CrossRef]
    [Google Scholar]
  23. Lunsford, R. D. & London, J. ( 1996; ). Natural genetic transformation in Streptococcus gordonii: comX imparts spontaneous competence on strain wicky. J Bacteriol 178, 5831–5835.
    [Google Scholar]
  24. Lunsford, R. D. & Roble, A. G. ( 1997; ). comYA, a gene similar to comGA of Bacillus subtilis, is essential for competence-factor-dependent DNA transformation in Streptococcus gordonii. J Bacteriol 179, 3122–3126.
    [Google Scholar]
  25. Luo, P. & Morrison, D. A. ( 2003; ). Transient association of an alternative sigma factor, ComX, with RNA polymerase during the period of competence for genetic transformation in Streptococcus pneumoniae. J Bacteriol 185, 349–358.[CrossRef]
    [Google Scholar]
  26. Magnuson, R., Solomon, J. & Grossman, A. D. ( 1994; ). Biochemical and genetic characterization of a competence pheromone from B. subtilis. Cell 77, 207–216.[CrossRef]
    [Google Scholar]
  27. Mascher, T., Zahner, D., Merai, M., Balmelle, N., de Saizieu, A. B. & Hakenbeck, R. ( 2003; ). The Streptococcus pneumoniae cia regulon: CiaR target sites and transcription profile analysis. J Bacteriol 185, 60–70.[CrossRef]
    [Google Scholar]
  28. Perry, D. & Kuramitsu, H. K. ( 1981; ). Genetic transformation of Streptococcus mutans. Infect Immun 32, 1295–1297.
    [Google Scholar]
  29. Pestova, E. V. & Morrison, D. A. ( 1998; ). Isolation and characterization of three Streptococcus pneumoniae transformation-specific loci by use of a lacZ reporter insertion vector. J Bacteriol 180, 2701–2710.
    [Google Scholar]
  30. Pestova, E. V., Havarstein, 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 Microbiol 21, 853–862.[CrossRef]
    [Google Scholar]
  31. Podbielski, A., Woischnik, M., Leonard, B. A. & Schmidt, K. H. ( 1999; ). Characterization of nra, a global negative regulator gene in group A streptococci. Mol Microbiol 31, 1051–1064.[CrossRef]
    [Google Scholar]
  32. Qi, F., Chen, P. & Caufield, P. W. ( 1999a; ). Functional analyses of the promoters in the lantibiotic mutacin II biosynthetic locus in Streptococcus mutans. Appl Environ Microbiol 65, 652–658.
    [Google Scholar]
  33. Qi, F., Chen, P. & Caufield, P. W. ( 1999b; ). Purification of mutacin III from group III Streptococcus mutans UA787 and genetic analyses of mutacin III biosynthesis genes. Appl Environ Microbiol 65, 3880–3887.
    [Google Scholar]
  34. Qi, F., Merritt, J., Lux, R. & Shi, W. ( 2004a; ). Inactivation of the ciaH gene in Streptococcus mutans diminishes mutacin production and competence development, alters sucrose-dependent biofilm formation, and reduces stress tolerance. Infect Immun 72, 4895–4899.[CrossRef]
    [Google Scholar]
  35. Quivey, R. G., Kuhnert, W. L. & Hahn, K. ( 2001; ). Genetics of acid adaptation in oral streptococci. Crit Rev Oral Biol Med 12, 301–314.[CrossRef]
    [Google Scholar]
  36. Shah, G. R. & Caufield, P. W. ( 1993; ). Enhanced transformation of Streptococcus mutans by modifications in culture conditions. Anal Biochem 214, 343–346.[CrossRef]
    [Google Scholar]
  37. Stentz, R. & Zagorec, M. ( 1999; ). Ribose utilization in Lactobacillus sakei: analysis of the regulation of the rbs operon and putative involvement of a new transporter. J Mol Microbiol Biotechnol 1, 165–173.
    [Google Scholar]
  38. Surette, M. G., Miller, M. B. & Bassler, B. L. ( 1999; ). Quorum sensing in Escherichia coli, Salmonella typhimurium, and Vibrio harveyi: a new family of genes responsible for autoinducer production. Proc Natl Acad Sci U S A 96, 1639–1644.[CrossRef]
    [Google Scholar]
  39. Tanzer, J. M., Livingston, J. & Thompson, A. M. ( 2001; ). The microbiology of primary dental caries in humans. J Dent Educ 65, 1028–1037.
    [Google Scholar]
  40. Yoshida, A. & Kuramitsu, H. K. ( 2002; ). Multiple Streptococcus mutans genes are involved in biofilm formation. Appl Environ Microbiol 68, 6283–6291.[CrossRef]
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journal/micro/10.1099/mic.0.27554-0
Loading
/content/journal/micro/10.1099/mic.0.27554-0
Loading

Data & Media loading...

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error