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Imaging InlC Secretion to Investigate Cellular Infection by the Bacterial Pathogen Listeria monocytogenes
14:05

Imaging InlC Secretion to Investigate Cellular Infection by the Bacterial Pathogen Listeria monocytogenes

Published on: September 19, 2013

Sigma B contributes to PrfA-mediated virulence in Listeria monocytogenes

Celine A Nadon1, Barbara M Bowen, Martin Wiedmann

  • 1Department of Food Science, Cornell University, Ithaca, New York 14853, USA.

Infection and Immunity
|June 18, 2002
PubMed

Insights

The alternative sigma factor sigma(B) influences Listeria monocytogenes virulence by regulating the positive regulatory factor A protein (PrfA) transcription. A sigB deletion mutation impacts the bacterium's virulence, highlighting sigma(B)'s role.

Area of Science:

  • Microbiology
  • Bacterial Pathogenesis
  • Molecular Biology

Background:

  • Listeria monocytogenes is an important foodborne pathogen.
  • The positive regulatory factor A protein (PrfA) is a key virulence regulator.
  • PrfA transcription is controlled by multiple promoters.

Purpose of the Study:

  • To investigate the role of the alternative sigma factor sigma(B) in regulating PrfA transcription.
  • To determine the contribution of sigma(B) to L. monocytogenes virulence.

Main Methods:

  • Analysis of prfA promoter activity.
  • Construction and characterization of a sigB deletion mutant in L. monocytogenes.
  • Assessment of the virulence phenotype of the mutant strain.

Main Results:

  • The prfAp(2) promoter was identified as a functional sigma(B)-dependent promoter.
  • A sigB deletion mutation significantly altered the virulence phenotype of L. monocytogenes.

Conclusions:

  • The alternative sigma factor sigma(B) plays a significant role in L. monocytogenes virulence.
  • Sigma(B) contributes to virulence by regulating PrfA expression through the prfAp(2) promoter.

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