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A Non-Coding Small RNA MicC Contributes to Virulence in Outer Membrane Proteins in Salmonella Enteritidis
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Effect of ompR gene mutation in expression of ompC and ompF of Salmonella typhi

Mahaboobbasha Malickbasha1, Ramaiah Arunachalam, Balakrishnan Senthilkumar

  • 1Centre for Biotechnology, Muthayammal College of Arts and Science, Rasipuram, TN, India.

Interdisciplinary Sciences, Computational Life Sciences
|July 20, 2010
PubMed

Insights

Two asymptomatic Salmonella typhi carriers were identified. The ompR-envZ system regulates Vi polysaccharide synthesis, with osmolarity as a potential environmental signal influencing outer membrane protein expression in Salmonella typhi.

Area of Science:

  • Microbiology
  • Molecular Biology
  • Genetics

Background:

  • Typhoid fever, caused by Salmonella Typhi, poses a significant public health challenge.
  • Asymptomatic carriers are crucial reservoirs for Salmonella Typhi transmission.
  • Understanding the regulatory mechanisms of virulence factors is essential for controlling typhoid.

Purpose of the Study:

  • To screen food handlers for asymptomatic Salmonella Typhi carriers.
  • To investigate the role of the ompR-envZ two-component regulatory system in Salmonella Typhi.
  • To determine the influence of osmolarity on outer membrane protein expression and Vi polysaccharide synthesis.

Main Methods:

  • Stool sample collection and microbiological analysis for Salmonella Typhi isolation.
  • Phylogenetic analysis and ompR gene sequencing.
  • Induction of mutations in Salmonella Typhi using varying sodium chloride concentrations.
  • Isolation and comparative analysis of outer membrane proteins using SDS-PAGE.

Main Results:

  • Two out of 50 food handlers were identified as asymptomatic carriers of Salmonella Typhi.
  • The ompR gene sequences of the isolates were determined and phylogenetic analysis was performed.
  • Variations in outer membrane protein expression were observed between wild-type and osmotically mutated Salmonella Typhi strains.
  • The ompR-envZ system was implicated in the regulation of Vi polysaccharide synthesis.

Conclusions:

  • The ompR-envZ two-component regulatory system plays a critical role in regulating Vi polysaccharide synthesis in Salmonella Typhi.
  • Osmolarity is identified as a potential environmental signal influencing this regulatory system.
  • Outer membrane protein expression in Salmonella Typhi is modulated by environmental osmolarity.

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