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Purification of a High Molecular Mass Protein in Streptococcus mutans
09:51

Purification of a High Molecular Mass Protein in Streptococcus mutans

Published on: September 14, 2019

Systemic inactivation and phenotypic characterization of two-component systems in expression of Streptococcus mutans

C M Lévesque1, R W Mair, J A Perry

  • 1Dental Research Institute, Faculty of Dentistry, University of Toronto, Toronto, ON, Canada. celine.levesque@dentistry.utoronto.ca

Letters in Applied Microbiology
|September 28, 2007
PubMed
Abstract

Insights

Two-component systems (TCS) regulate Streptococcus mutans virulence. TCS-2, TCS-3, and TCS-9 impact biofilm formation, acid tolerance, and competence, crucial for S. mutans survival and pathogenesis.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Bacterial Pathogenesis

Background:

  • Streptococcus mutans is a primary cause of dental caries.
  • Virulence factors of S. mutans are essential for its survival and pathogenicity.
  • Two-component systems (TCS) are key regulators of bacterial adaptation and virulence.

Purpose of the Study:

  • To investigate the role of individual TCS in regulating S. mutans virulence properties.
  • To elucidate the function of specific TCS in biofilm formation, competence, and stress tolerance.

Main Methods:

  • Gene inactivation of histidine kinase-encoding genes using PCR-based deletion.
  • Assessment of biofilm formation, competence development, and tolerance to acid, osmotic, and oxidative stress.
  • Phenotypic analysis of S. mutans mutants lacking specific TCS.

Main Results:

  • No lethal mutations were observed in S. mutans.
  • TCS-2 (CiaRH) is crucial for biofilm formation and environmental stress tolerance.
  • TCS-3 (ScnRK-like) enhances survival at acidic pH.
  • TCS-9 influences acid tolerance response and competence development.

Conclusions:

  • TCS play significant physiological roles in S. mutans.
  • SncRK-like TCS and TCS-9 are potential novel regulatory systems involved in S. mutans pathogenesis.
  • Multiple TCS collectively regulate S. mutans survival and persistence within the biofilm community.

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