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Updated: May 16, 2025
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Phage Phenomics: Physiological Approaches to Characterize Novel Viral Proteins
Published on: June 11, 2015
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Adaptive genomic plasticity in large-genome, broad-host-range vibrio phages
Charles Bernard1, Yannick Labreuche2,3,4, Carine Diarra5
1Institut Pasteur, Université de Paris, Centre nationale de la recherche scientifique (CNRS), Unité mixte de recherche (UMR) 3525, Microbial Evolutionary Genomics, 28 rue du Dr Roux, 75015 Paris, France.
The ISME Journal
|April 4, 2025
Summary
Broad-host-range Schizotequatroviruses adapt through genetic recombination, enabling receptor switching. Despite their adaptability, these phages are rare in marine environments due to ecological factors.
Area of Science:
- Microbiology
- Virology
- Marine Ecology
Background:
- The host range of bacteriophages is crucial for understanding phage ecology and applications.
- Broad-host-range phages are significant in marine ecosystems, but the mechanisms driving their generalism are poorly understood.
Purpose of the Study:
- To analyze the genetic and evolutionary mechanisms of broad-host-range Schizotequatroviruses.
- To investigate the ecological factors influencing their prevalence in marine environments.
Main Methods:
- Genomic analysis of Schizotequatroviruses and their Vibrio crassostreae hosts.
- Identification of recombination hotspots and genes involved in host adaptation.
- In vitro burst size assays and environmental prevalence assessment.
Main Results:
- Schizotequatroviruses possess large genomes with conserved organization and recombination hotspots.
- Recombination events in receptor-binding proteins and antidefense systems facilitate adaptation.
- Some lineages exhibit receptor-switching capabilities (OmpK and LamB).
- Despite broad host range, Schizotequatroviruses are rare, not due to burst size, but potentially ecological constraints or fitness trade-offs.
Conclusions:
- Genetic recombination and receptor-switching are key to Schizotequatrovirus generalism.
- Ecological factors, not intrinsic phage properties, likely explain their environmental rarity.
- Findings inform phage applications in aquaculture and beyond.
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