RsbV of Listeria monocytogenes contributes to regulation of environmental stress and virulence

Arch Microbiol. 2013 Feb;195(2):113-20. doi: 10.1007/s00203-012-0855-5. Epub 2012 Nov 29.

Abstract

SigmaB factor is an important regulatory factor for stress response in Gram-positive bacteria such as Listeria monocytogenes (L. monocytogenes), Staphylococcus aureus and Bacillus subtilis. However, the activity of SigmaB factor is regulated by RsbV factor. Currently, the functional studies of RsbV factor are mostly focused on non-pathogenic B. subtilis, but the roles of RsbV factor in pathogenic L. monocytogenes during the regulation of environmental stress and virulence are still unclear. In the study, a ∆RsbV mutant of L. monocytogenes was constructed to explore the regulatory role of RsbV in environmental stress and virulence. The environmental stress experiments indicated that the growth and survival capability of ∆RsbV mutant obviously decreased in stress of low temperature, osmotic pressure, alcohol and acid, compared with EGD strain. The macrophage infection experiment indicated that ∆RsbV mutant had weaker survival capability than EGD strain, and the expression of PrfA, actA, PlcA and LLO was down-regulated in infected cells. Animal inoculation experiments indicated that RsbV deletion significantly reduced the pathogenicity of L. monocytogenes. Our data demonstrate that, in addition to regulating tolerance under environmental stress conditions, RsbV also contributes to regulation of L. monocytogenes virulence.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Acids / pharmacology
  • Animals
  • Bacterial Proteins / genetics
  • Bacterial Proteins / metabolism*
  • Cell Line
  • Cold Temperature
  • Environment
  • Genes, Bacterial
  • Listeria monocytogenes / genetics
  • Listeria monocytogenes / growth & development
  • Listeria monocytogenes / pathogenicity*
  • Macrophages / microbiology
  • Mice
  • Mice, Inbred BALB C
  • Mutation
  • Octoxynol / pharmacology
  • Osmotic Pressure
  • Oxidative Stress
  • Sodium Chloride / pharmacology
  • Stress, Physiological*
  • Transcription, Genetic
  • Virulence

Substances

  • Acids
  • Bacterial Proteins
  • RsbV protein, Bacteria
  • Sodium Chloride
  • Octoxynol