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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
Interplay between two RND systems mediating antimicrobial resistance in Brucella suis
Fernando A Martin1, Diana M Posadas, Mariela C Carrica
1Fundación Instituto Leloir, IIBBA CONICET and FCEyN, Universidad de Buenos Aires, Patricias Argentinas 435, (C1405BWE) Buenos Aires, Argentina.
Journal of Bacteriology
|February 10, 2009
Summary
Brucella suis possesses two RND efflux pumps, BepDE and BepFG, that confer multidrug resistance and contribute to bacterial virulence. Deletion mutants revealed their roles in drug efflux and intracellular survival.
Area of Science:
- Microbiology
- Molecular Biology
- Biochemistry
Background:
- RND-type efflux pumps are crucial for multidrug resistance in bacteria.
- These pumps are also implicated in the virulence mechanisms of pathogenic bacteria.
- Brucella suis utilizes efflux pumps for drug resistance and potentially virulence.
Purpose of the Study:
- To characterize two novel RND efflux pump components (BepDE and BepFG) in Brucella suis.
- To investigate the roles of these pumps in drug resistance and virulence.
- To elucidate the regulatory mechanisms governing these efflux systems.
Main Methods:
- Minimum Inhibitory Concentration (MIC) assays were performed on B. suis mutants.
- Gene expression analysis using promoter activity assays.
- Assessment of bacterial behavior in model cell systems and intracellular environments.
Main Results:
- Deletion of bepE increased sensitivity to deoxycholate, ethidium bromide, and crystal violet.
- Overexpression of bepDE enhanced resistance to multiple drugs.
- Both bepDE and bepFG promoters were induced intracellularly, suggesting a role in virulence.
Conclusions:
- Brucella suis harbors at least two functional RND efflux pumps, BepDE and BepFG.
- These pumps contribute significantly to multidrug resistance.
- The efflux systems are likely involved in the intracellular survival and virulence of Brucella suis.
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