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Porphyromonas gingivalis as a Model Organism for Assessing Interaction of Anaerobic Bacteria with Host Cells
Published on: December 17, 2015
Periodontal pathogens interfere with quorum-sensing-dependent virulence properties in Streptococcus mutans
1Department of Periodontics and Endodontics, University at Buffalo, State University of New York, Buffalo, NY 14214, USA. bwang@buffalo.edu
Journal of Periodontal Research
|November 27, 2010
Summary
Periodontal pathogens like Porphyromonas gingivalis and Treponema denticola disrupt Streptococcus mutans quorum sensing. This antagonism may reduce S. mutans virulence and environmental resistance, impacting oral microbial communities.
Area of Science:
- Oral microbiology
- Bacterial communication
- Periodontal disease pathogenesis
Background:
- The dominance of periodontal pathogens at disease sites remains unclear.
- One hypothesis suggests late colonizers may interfere with early colonizer quorum sensing, increasing susceptibility to environmental factors.
Purpose of the Study:
- To investigate if periodontal pathogens antagonize the quorum-sensing systems of early colonizers, specifically Streptococcus mutans.
- To evaluate the impact of Porphyromonas gingivalis and Treponema denticola on S. mutans quorum-sensing-dependent properties.
Main Methods:
- Utilized Streptococcus mutans strains (NG8, LT11, BM71) for transformation and bacteriocin production assays.
- Conducted mixed-broth assays with periodontal pathogens Porphyromonas gingivalis and Treponema denticola to assess effects on S. mutans competence-stimulating peptide-dependent properties.
Main Results:
- P. gingivalis and T. denticola (live or membrane vesicles) inhibited S. mutans transformation and bacteriocin production.
- Inhibition was dependent on viable bacteria; boiling abolished this effect.
- Periodontal pathogens inactivated S. mutans exogenous competence-stimulating peptide.
Conclusions:
- Periodontal pathogens antagonize Streptococcus mutans quorum-sensing mechanisms.
- This antagonism may decrease S. mutans virulence and its resistance to environmental antibacterial factors.
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