1887

Abstract

One of the striking characteristics of is the extensive genetic diversity among clinical isolates. This diversity has been attributed to an elevated mutation rate, impaired DNA repair, DNA transfer and frequent recombination events. Plasmids have also been identified in but it remained unknown whether conjugation can contribute to DNA transfer between clinical isolates. To examine whether possesses intrinsic capability for conjugative plasmid transfer, shuttle vectors were introduced into containing an sequence of the conjugative IncP plasmid RP4 but no mobilization () genes. It was shown that these vectors could stably replicate and be mobilized among clinical strains. It was also demonstrated that and relaxase () homologues carried on the chromosome were important for plasmid transfer. Primer extension studies and mutagenesis further confirmed that the relaxase homologue in encodes a functional enzyme capable of acting on the RP4 . Furthermore, the findings of this study indicate that and act independently of the previously described type IV secretion systems, including that encoded by the pathogenicity island and the transformation apparatus, in mediating conjugative plasmid DNA transfer between strains.

Loading

Article metrics loading...

/content/journal/micro/10.1099/mic.0.28250-0
2005-11-01
2024-03-29
Loading full text...

Full text loading...

/deliver/fulltext/micro/151/11/3493.html?itemId=/content/journal/micro/10.1099/mic.0.28250-0&mimeType=html&fmt=ahah

References

  1. Akopyanz N., Bukanov N. O., Westblom T. U., Kresovich S., Berg D. E. 1992; DNA diversity among clinical isolates of Helicobacter pylori detected by PCR-based RAPD fingerprinting. Nucleic Acids Res 20:5137–5142 [CrossRef]
    [Google Scholar]
  2. Alm R. A., Ling L. S., Moir D. T. & 20 other authors; 1999; Genomic-sequence comparison of two unrelated isolates of the human gastric pathogen Helicobacter pylori . Nature 397:176–180 [CrossRef]
    [Google Scholar]
  3. Alm R. A., Trust T. J. 1999; Analysis of the genetic diversity of Helicobacter pylori : the tale of two genomes. J Mol Med 77:834–846 [CrossRef]
    [Google Scholar]
  4. Aras R. A., Small A. J., Ando T., Blaser M. J. 2002; Helicobacter pylori interstrain restriction-modification diversity prevents genome subversion by chromosomal DNA from competing strains. Nucleic Acids Res 30:5391–5397 [CrossRef]
    [Google Scholar]
  5. Backert S., Meißner K., Börner T. 1997; Unique features of a mitochondrial rolling circle-plasmid mp1 from the higher plant Chenopodium album (L.). Nucleic Acids Res 25:582–590 [CrossRef]
    [Google Scholar]
  6. Backert S., von Nickisch-Rosenegk E., Meyer T. F. 1998; Potential role of two Helicobacter pylori relaxases in DNA transfer?. Mol Microbiol 30:673–674 [CrossRef]
    [Google Scholar]
  7. Backert S., Moese S., Selbach S., Brinkmann V., Meyer T. F. 2001; Phosphorylation of tyrosine 972 of the Helicobacter pylori CagA protein is essential for induction of a scattering phenotype in gastric epithelial cells. Mol Microbiol 42:631–644
    [Google Scholar]
  8. Backert S., Churin Y., Meyer T. F. 2002; Helicobacter pylori type IV secretion, host cell signalling and vaccine development. Keio J Med 51: Suppl 26–14 [CrossRef]
    [Google Scholar]
  9. Backert S., Schwarz T., Sommer Ch. 7 other authors 2004; Function of the cag pathogenicity island in Helicobacter pylori isolated from patients with gastritis, peptic ulcer and gastric cancer. Infect Immun 72:1043–1056 [CrossRef]
    [Google Scholar]
  10. Balzer D., Pansegrau W., Lanka E. 1994; Essential motifs of relaxase (TraI) and TraG proteins involved in conjugative transfer of plasmid RP4. J Bacteriol 176:4285–4295
    [Google Scholar]
  11. Brandt S., Kwok T., Hartig R., König W., Backert S. 2005; NF- κ B-activation and potentiation of proinflammatory responses by the Helicobacter pylori CagA protein. Proc Natl Acad Sci U S A 102:9300–9305 [CrossRef]
    [Google Scholar]
  12. Cabezon E., Sastre J. I., de la Cruz F. 1997; Genetic evidence of a coupling role for the TraG protein family in bacterial conjugation. Mol Gen Genet 254:400–406 [CrossRef]
    [Google Scholar]
  13. Cascales E., Christie P. 2003; The versatile bacterial type IV secretion systems. Nature Rev Microbiol 1:137–148 [CrossRef]
    [Google Scholar]
  14. Censini S., Lange C., Xiang Z., Crabtree J. E., Ghiara P., Borodovsky M., Rappuoli R., Covacci A. 1996; cag , a pathogenicity island of Helicobacter pylori , encodes type I-specific and disease-associated virulence factors. Proc Natl Acad Sci U S A 93:14648–14653 [CrossRef]
    [Google Scholar]
  15. Covacci A., Rappuoli R. 2000; Tyrosine-phosphorylated bacterial proteins: Trojan horses for the host cell. J Exp Med 191:587–592 [CrossRef]
    [Google Scholar]
  16. De Ungria M. C., Kolesnikow T., Cox P. T., Lee A. 1999; Molecular characterization and interstrain variability of pHPS1, a plasmid isolated from the Sydney strain (SS1) of Helicobacter pylori . Plasmid 41:97–109 [CrossRef]
    [Google Scholar]
  17. Gieseler S., Koenig B., Koenig W., Backert S. 2005; Strain-specific expression profiles of virulence genes in Helicobacter pylori during infection of gastric epithelial cells and granulocytes. Microbes Infect 7:437–447 [CrossRef]
    [Google Scholar]
  18. Gomis-Ruth F. X., Moncalian G., Perez-Luque R., Gonzalez A., Cabezon E., de la Cruz F., Coll M. 2001; The bacterial conjugation protein TrwB resembles ring helicases and F1-ATPase. Nature 409:637–641 [CrossRef]
    [Google Scholar]
  19. Goodwin A., Kersulyte D., Sisson G., Veldhuyzen van Zanten S. J., Berg D. E., Hoffman P. S. 1998; Metronidazole resistance in Helicobacter pylori is due to null mutations in a gene ( rdxA ) that encodes an oxygen-insensitive NADPH nitroreductase. Mol Microbiol 28:383–393 [CrossRef]
    [Google Scholar]
  20. Heuermann D., Haas R. 1995; Genetic organization of a small cryptic plasmid of Helicobacter pylori . Gene 165:17–24 [CrossRef]
    [Google Scholar]
  21. Heuermann D., Haas R. 1998; A stable shuttle vector system for efficient genetic complementation of Helicobacter pylori strains by transformation and conjugation. Mol Gen Genet 257:519–528 [CrossRef]
    [Google Scholar]
  22. Hofler C., Fischer W., Hofreuter D., Haas R. 2004; Cryptic plasmids in Helicobacter pylori : putative functions in conjugative transfer and microcin production. Int J Med Microbiol 294:141–148 [CrossRef]
    [Google Scholar]
  23. Hofreuter D., Haas R. 2002; Characterization of two cryptic Helicobacter pylori plasmids: a putative source for horizontal gene transfer and gene shuffling. J Bacteriol 184:2755–2766 [CrossRef]
    [Google Scholar]
  24. Hofreuter D., Odenbreit S., Haas R. 2001; Natural transformation competence in Helicobacter pylori is mediated by the basic components of a type IV secretion system. Mol Microbiol 41:379–391 [CrossRef]
    [Google Scholar]
  25. Hormaeche I., Alkorta I., Moro F., Valpuesta J. M., Goni F. M., de La Cruz F. 2002; Purification and properties of TrwB, a hexameric, ATP-binding integral membrane protein essential for R388 plasmid conjugation. J Biol Chem 277:46456–46462 [CrossRef]
    [Google Scholar]
  26. Israel D. A., Salama N., Krishna U., Rieger U. M, Atherton J. C., Falkow S., Peek R. M. Jr 2001; Helicobacter pylori genetic diversity within the gastric niche of a single human host. Proc Natl Acad Sci U S A 98:14625–14630 [CrossRef]
    [Google Scholar]
  27. Kahrs A. F., Odenbreit S., Schmitt W., Heuermann D., Meyer T. F., Haas R. 1995; An improved TnMax mini-transposon system suitable for sequencing, shuttle mutagenesis and gene fusions. Gene 167:53–57 [CrossRef]
    [Google Scholar]
  28. Kersulyte D., Velapatino B., Mukhopadhyay A. K., Cahuayme L., Bussalleu A., Combe J., Gilman R. H., Berg D. E. 2003; Cluster of type IV secretion genes in Helicobacter pylori 's plasticity zone. J Bacteriol 185:3764–3772 [CrossRef]
    [Google Scholar]
  29. Kleanthous H., Clayton C. L., Tabaqchali S. 1991; Characterization of a plasmid from Helicobacter pylori encoding a replication protein common to plasmids in gram-positive bacteria. Mol Microbiol 5:2377–2389 [CrossRef]
    [Google Scholar]
  30. Kuipers E. J., Israel D. A., Kusters J. G., Blaser M. J. 1998; Evidence for a conjugation-like mechanism of DNA transfer in Helicobacter pylori . J Bacteriol 180:2901–2905
    [Google Scholar]
  31. Lin L. F., Posfai J., Roberts R. J., Kong H. 2001; Comparative genomics of the restriction-modification systems in Helicobacter pylori . Proc Natl Acad Sci U S A 98:2740–2745 [CrossRef]
    [Google Scholar]
  32. Liu Y., Haggard-Ljungquist E. 1994; Studies of bacteriophage P2 DNA replication: localization of the cleavage site of the A protein. Nucleic Acids Res 22:5204–5210 [CrossRef]
    [Google Scholar]
  33. Llosa M., Grandoso G., de la Cruz F. 1995; Nicking activity of TrwC directed against the origin of transfer of the IncW plasmid R388. J Mol Biol 246:54–62 [CrossRef]
    [Google Scholar]
  34. Llosa M., Gomis-Ruth F. X., Coll M., de la Cruz F. 2002; Bacterial conjugation: a two-step mechanism for DNA transport. Mol Microbiol 45:1–8 [CrossRef]
    [Google Scholar]
  35. Minnis J. A., Taylor T. E., Knesek J. E., Peterson W. L., McIntire S. A. 1995; Characterization of a 3·5-kbp plasmid from Helicobacter pylori . Plasmid 34:22–36 [CrossRef]
    [Google Scholar]
  36. Montecucco C., Rappuoli R. 2001; Living dangerously: how Helicobacter pylori survives in the human stomach. Nature Rev Mol Cell Biol 2:457–466
    [Google Scholar]
  37. Nobusato A., Uchiyama I., Kobayashi I. 2000; Diversity of restriction-modification gene homologues in Helicobacter pylori . Gene 259:89–98 [CrossRef]
    [Google Scholar]
  38. Odenbreit S., Till M., Haas R. 1996; Optimized BlaM-transposon shuttle mutagenesis of Helicobacter pylori allows the identification of novel genetic loci involved in bacterial virulence. Mol Microbiol 20:361–373 [CrossRef]
    [Google Scholar]
  39. Pansegrau W., Lanka E. 1996; Enzymology of DNA transfer by conjugative mechanisms. Prog Nucleic Acid Res Mol Biol 54:197–251
    [Google Scholar]
  40. Pansegrau W., Ziegelin G., Lanka E. 1990; Covalent association of the traI gene product of plasmid RP4 with the 5′-terminal nucleotide at the relaxation nick site. J Biol Chem 265:10637–10644
    [Google Scholar]
  41. Peek R. M. Jr, Blaser M. J. 2002; Helicobacter pylori and gastrointestinal tract adenocarcinomas. Nat Rev Cancer 2:28–37 [CrossRef]
    [Google Scholar]
  42. Penfold S. S., Lastovica A. J., Elisha B. G. 1988; Demonstration of plasmids in Campylobacter pylori . J Infect Dis 157:850–851 [CrossRef]
    [Google Scholar]
  43. Salama N., Guillemin K., McDaniel T. K., Sherlock G., Tompkins L., Falkow S. 2000; A whole-genome microarray reveals genetic diversity among Helicobacter pylori strains. Proc Natl Acad Sci U S A 97:14668–14673 [CrossRef]
    [Google Scholar]
  44. Schroder G., Lanka E. 2003; TraG-like proteins of type IV secretion systems: functional dissection of the multiple activities of TraG (RP4) and TrwB (R388). J Bacteriol 185:4371–4381 [CrossRef]
    [Google Scholar]
  45. Schroder G., Lanka E. 2005; The mating pair formation system of conjugative plasmids – a versatile secretion machinery for transfer of proteins and DNA. Plasmid 54:1–25 [CrossRef]
    [Google Scholar]
  46. Schroder G., Krause S., Zechner E. L., Traxler B., Yeo H. J., Lurz R., Waksman G., Lanka E. 2002; TraG-like proteins of DNA transfer systems and of the Helicobacter pylori type IV secretion system: inner membrane gate for exported substrates?. J Bacteriol 184:2767–2779 [CrossRef]
    [Google Scholar]
  47. Suerbaum S., Achtman M. 2004; Helicobacter pylori : recombination, population structure and human migrations. Int J Med Microbiol 294:133–139 [CrossRef]
    [Google Scholar]
  48. Tato I., Zunzunegui S., de la Cruz F., Cabezon E. 2005; TrwB, the coupling protein involved in DNA transport during bacterial conjugation, is a DNA-dependent ATPase. Proc Natl Acad Sci U S A 102:8156–8161 [CrossRef]
    [Google Scholar]
  49. Tomb J. F., White O., Kerlavage A. R. 39 other authors 1997; The complete genome sequence of the gastric pathogen Helicobacter pylori . Nature 388:539–547 [CrossRef]
    [Google Scholar]
  50. Walker J. E., Saraste M., Runswick M. J., Gay N. J. 1982; Distantly related sequences in the α - and β -subunits of ATP synthase, myosin, kinases, and other ATP-requiring enzymes and a common nucleotide binding fold. EMBO J 1:945–951
    [Google Scholar]
http://instance.metastore.ingenta.com/content/journal/micro/10.1099/mic.0.28250-0
Loading
/content/journal/micro/10.1099/mic.0.28250-0
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