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The Citrobacter rodentium Mouse Model: Studying Pathogen and Host Contributions to Infectious Colitis
Published on: February 19, 2013
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The CpxRA two-component system is essential for Citrobacter rodentium virulence
Jenny-Lee Thomassin1, Natalia Giannakopoulou1, Lei Zhu1
1Department of Microbiology and Immunology, McGill University, Montreal, Quebec, Canada.
Infection and Immunity
|February 26, 2015
Summary
The CpxRA two-component system is crucial for Citrobacter rodentium virulence in mice. Deleting cpxRA protects mice from lethal infection, highlighting its role in pathogenesis and potential as a therapeutic target.
Area of Science:
- Microbiology
- Pathogenesis
- Molecular Biology
Background:
- Citrobacter rodentium serves as a model for human enteric pathogens like E. coli.
- Pathogenic bacteria utilize two-component signal transduction systems for environmental adaptation during infection.
- The CpxRA system in E. coli responds to envelope stress by regulating gene expression.
Purpose of the Study:
- To investigate the role of the CpxRA two-component system in C. rodentium virulence.
- To determine if cpxRA expression is modulated during C. rodentium infection in vivo.
- To assess the potential of CpxRA as a therapeutic target.
Main Methods:
- Quantitative real-time PCR to measure cpxRA expression in infected mouse colons.
- Generation and characterization of a cpxRA deletion mutant strain of C. rodentium.
- Infection studies in C57BL/6J and C3H/HeJ mice to assess virulence and survival rates.
Main Results:
- cpxRA was expressed in the colon during C. rodentium infection.
- A cpxRA deletion mutant exhibited a colonization defect independent of growth rate or type III secretion.
- Mice infected with the ΔcpxRA strain showed increased survival in a lethal infection model compared to wild-type.
- Higher cpxRA expression was observed during early infection stages.
Conclusions:
- The CpxRA two-component system is essential for C. rodentium virulence in vivo.
- Fine-tuned expression of cpxRA is critical for effective infection.
- CpxRA represents a novel target for developing therapeutics against enteric pathogens.
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