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Author Spotlight: Efficiently Eliminating Bacteriophages from Infected Salmonella Cultures Using Lipopolysaccharides
Published on: June 28, 2024
809
A prophage competition element protects Salmonella from lysis
Molly R Sargen1, Sophie Helaine1
1Department of Microbiology, Harvard Medical School, 77 Avenue Louis Pasteur, Boston, MA 02115, USA.
Cell Host & Microbe
|November 8, 2024
Summary
Bacteria with multiple prophages face a lethal threat from reactivation. A newly discovered element, RemAIN, blocks this process, influencing bacterial persistence and host immune response during infection.
Area of Science:
- Microbiology
- Molecular Biology
- Immunology
Background:
- Most bacteria are polylysogens, harboring multiple integrated prophages.
- Prophages offer benefits but can reactivate upon DNA damage, leading to bacterial lysis.
- Prophage activation is likely during infection due to host immune-induced DNA damage.
Purpose of the Study:
- To investigate prophage induction consequences in Salmonella.
- To identify mechanisms of prophage competition during bacterial infection.
Main Methods:
- Studied prophage induction in Salmonella.
- Identified and characterized a novel prophage element named RemAIN.
- Assessed the impact of RemAIN on co-resident prophages and bacterial persistence.
Main Results:
- Discovered the Gifsy-1 prophage encodes RemAIN, a ribonuclease effector module with ATPase, inhibitor, and nuclease activity.
- RemAIN inhibits lytic cycles and viral particle release of co-resident prophages.
- RemAIN activation in intramacrophage Salmonella persisters influences bacterial persistence and macrophage response.
Conclusions:
- Prophage-prophage competition is a key factor in bacterial persistence.
- RemAIN represents a novel mechanism of viral interference within bacterial populations.
- This discovery reveals a complex host-pathogen-prophage interaction influencing infection dynamics and immune response.
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