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Microscopy-based Assays for High-throughput Screening of Host Factors Involved in Brucella Infection of Hela Cells
Published on: August 5, 2016
Extensive cell envelope modulation is associated with virulence in Brucella abortus.
Julie Lamontagne1, Heather Butler, Esteban Chaves-Olarte
1Caprion Pharmaceuticals, 7150 Alexander-Fleming, Montreal, Quebec, Canada H4S 2C8.
Journal of Proteome Research
|March 9, 2007
Summary
The BvrR/BvrS system significantly impacts Brucella abortus cell envelope proteins, affecting virulence. Changes in outer membrane and periplasmic proteins in mutants suggest a link between cell envelope function, metabolism, and bacterial virulence.
Area of Science:
- Microbiology
- Proteomics
- Bacterial Pathogenesis
Background:
- Brucella virulence is associated with cell envelope components.
- The BvrR/BvrS system is crucial for Brucella virulence.
Purpose of the Study:
- To quantify the impact of the BvrR/BvrS system on cell envelope proteins in Brucella abortus.
- To investigate the relationship between cell envelope protein expression and bacterial virulence.
Main Methods:
- Label-free mass spectrometry-based proteomic analysis.
- Comparative analysis of outer membrane fragments from wild type and mutant Brucella abortus strains.
- Analysis of spontaneously released outer membrane fragments.
Main Results:
- Identified 167 differentially expressed proteins, with 25 in the outer membrane.
- Observed reciprocal changes in outer membrane proteins (decreased Omp3 family, increased lipoproteins) in avirulent mutants.
- Found increased periplasmic proteins in mutants, suggesting a potential nutritional stress response.
Conclusions:
- The BvrR/BvrS system regulates a wide range of cell envelope proteins, influencing Brucella virulence.
- Brucella virulence likely depends on integrated regulatory networks of cell envelope and metabolism.
- The findings may apply to other alpha-Proteobacteria with BvrR/BvrS orthologous systems.
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