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06:15
Evaluating Virulence and Pathogenesis of Aeromonas Infection in a Caenorhabditis elegans Model
Published on: December 20, 2018
Iron acquisition and virulence in the motile aeromonads: siderophore-dependent and -independent systems
B R Byers1, G Massad, S Barghouthi
1Department of Microbiology, University of Mississippi Medical Center, Jackson 39216-4505.
Experientia
|May 15, 1991
Abstract:
During an infection, a microbial pathogen must acquire all of its iron from the host. Aeromonas isolated producing the siderophore amonabactin obtain iron either from host Fe-transferrin (siderophore dependent) or from host heme-containing molecules (siderophore independent). Isolates producing the siderophore enterobactin do not utilize Fe-transferrin in serum and probably rely exclusively on host heme iron.
Insights
Aeromonas bacteria use different strategies to obtain iron from hosts during infection. Some use siderophore-dependent methods like Fe-transferrin, while others rely on heme iron.
Area of Science:
- Microbiology
- Infectious Diseases
- Bacterial Pathogenesis
Background:
- Microbial pathogens require host iron for survival and proliferation during infection.
- Iron acquisition is a critical factor in bacterial pathogenesis.
- Aeromonas species are known opportunistic pathogens that must adapt to host iron sources.
Purpose of the Study:
- To investigate the iron acquisition mechanisms employed by different Aeromonas isolates.
- To differentiate between siderophore-dependent and siderophore-independent iron uptake strategies in Aeromonas.
- To understand the utilization of host iron sources, specifically Fe-transferrin and heme, by Aeromonas.
Main Methods:
- Isolation and characterization of Aeromonas strains.
- Analysis of siderophore production (amonabactin and enterobactin).
- Assays to determine iron utilization from Fe-transferrin and heme-containing molecules.
Main Results:
- Aeromonas isolates producing amonabactin can utilize iron from Fe-transferrin (siderophore-dependent) and heme-containing molecules (siderophore-independent).
- Aeromonas isolates producing enterobactin do not utilize Fe-transferrin and appear to rely exclusively on heme iron.
- This demonstrates distinct iron acquisition strategies within Aeromonas species.
Conclusions:
- Aeromonas species exhibit diverse iron acquisition mechanisms, adapting to available host iron sources.
- The type of siderophore produced influences the pathogen's ability to utilize specific host iron compounds.
- Understanding these mechanisms is crucial for developing strategies to combat Aeromonas infections.
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