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Author Spotlight: Investigating Bacteriophage-Induced Immune Responses in Gnotobiotic Mice
Published on: January 26, 2024
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Structural modeling reveals phage proteins that manipulate bacterial immune signaling
Nitzan Tal1, Romi Hadary1, Renee B Chang2,3
1Department of Molecular Genetics, Weizmann Institute of Science, Rehovot, Israel.
Science (New York, N.Y.)
|March 5, 2026
Summary
Viruses block bacterial immunity by targeting nucleotide signals. Researchers discovered new viral proteins (Sequestin, Lockin, Acb5) that disrupt bacterial defense systems like Thoeris and cyclic oligonucleotide-based antiphage signaling (CBASS).
Area of Science:
- Microbiology
- Virology
- Molecular Biology
Background:
- Bacterial immune systems utilize intracellular nucleotide signaling.
- Viruses counteract these defenses by interfering with nucleotide signals.
Purpose of the Study:
- To identify and characterize viral proteins that manipulate bacterial immune signaling.
- To understand the mechanisms by which viruses evade bacterial defenses.
Main Methods:
- Computational pipeline developed to predict phage proteins targeting bacterial immunity.
- Experimental validation of predicted proteins using biochemical and structural analyses.
- Assays to determine binding and catalytic activities of identified protein families.
Main Results:
- Discovered three novel protein families: Sequestin, Lockin, and Acb5.
- These proteins inhibit the Thoeris system and cyclic oligonucleotide-based antiphage signaling (CBASS).
- Sequestin and Lockin act as nucleotide binders, while Acb5 is a nuclease.
Conclusions:
- Viral antidefense proteins share conserved structural and biophysical traits.
- A diverse array of viral strategies exists to subvert nucleotide-based bacterial immunity.
- Thousands of homologs in phage genomes indicate widespread viral manipulation of host defenses.
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