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Updated: Dec 21, 2025
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Author Spotlight: Advancements in Understanding and Combatting Shigella Infections
Published on: February 9, 2024
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Ecology, Structure, and Evolution of Shigella Phages
Sundharraman Subramanian1, Kristin N Parent1, Sarah M Doore1,2
1Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan 48824, USA.
Annual Review of Virology
|May 12, 2020
Summary
Shigella phages, viruses that infect Shigella bacteria, are abundant and possess unique genomic and structural traits. Research highlights their distinct evolutionary paths and infection mechanisms compared to other bacteriophages.
Area of Science:
- Microbiology
- Virology
- Genomics
Background:
- Bacteriophages (phages) are viruses that infect bacteria.
- While numerous phages exist for various bacterial species, few were previously known to exclusively infect the Gram-negative *Shigella* genus.
- Recent studies reveal a surprising abundance of *Shigella* phages in the environment.
Purpose of the Study:
- To review the history and recent advancements in the isolation and characterization of *Shigella* phages.
- To discuss the distinct genomic and structural properties of these phages.
- To explore potential selective pressures influencing the co-evolution of *Shigella* phages and their hosts.
Main Methods:
- Literature review of historical and recent studies on *Shigella* phages.
- Analysis of genomic and structural data for key *Shigella* phage model systems (Sf6, Sf14, HRP29).
- Discussion of experimental evolution studies revealing unique phage infection mechanisms.
Main Results:
- *Shigella* phages are environmentally abundant and exhibit unique genomic and structural features.
- Distinct evolutionary trajectories and ecological roles are suggested for *Shigella* phages compared to other well-characterized phage systems.
- A novel mechanism for accelerated infection cycles has been identified in at least one *Shigella* phage model system.
Conclusions:
- *Shigella* phages represent a distinct group of bacteriophages with unique biological properties.
- Their differences may reflect the specific ecology and defense mechanisms of *Shigella* hosts.
- Further research into *Shigella* phage biology can provide insights into phage-host co-evolutionary dynamics.
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