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Bacterial behaviors associated with the quorum-sensing peptide pheromone ('alarmone') in streptococci

Delphine Dufour1, Céline M Lévesque

  • 1Dental Research Institute, Faculty of Dentistry, University of Toronto, 124 Edward St, Room 454B, Toronto, ON, M5G 1G6, Canada.

Future Microbiology
|May 7, 2013
PubMed

Insights

Oral streptococci use a stress-induced peptide pheromone as an alarmone. This allows them to coordinate gene expression and synchronize cellular activities for survival in the human body.

Area of Science:

  • Microbiology
  • Bacterial Pathogenesis
  • Molecular Biology

Background:

  • Streptococci are common human commensals, but can cause various infections.
  • These bacteria possess sophisticated stress response mechanisms for survival.
  • Oral streptococci colonize the mouth and upper respiratory tract, facing environmental challenges.

Purpose of the Study:

  • To investigate the role of quorum-sensing peptides in streptococcal stress responses.
  • To understand how oral streptococci coordinate gene expression for persistence.
  • To elucidate the function of stress-inducible 'alarmones' in bacterial survival.

Main Methods:

  • Analysis of quorum-sensing signaling pathways in oral streptococci.
  • Gene expression profiling under various stress conditions.
  • Identification and characterization of stress-inducible peptide pheromones.

Main Results:

  • Oral streptococci utilize a specific quorum-sensing peptide pheromone as a stress-inducible alarmone.
  • This alarmone synchronizes gene expression within a population of cells.
  • Coordinated cellular activities enhance streptococcal persistence and survival against stressors.

Conclusions:

  • Quorum-sensing peptides are crucial for streptococcal stress adaptation.
  • Alarmone-mediated synchronization facilitates survival in the human host.
  • Understanding these mechanisms offers insights into bacterial pathogenesis and host-microbe interactions.

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