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Published on: June 28, 2024
Phenotypic and genotypic variations within a single bacteriophage species
Pieter-Jan Ceyssens1, Thea Glonti, Ndrew M Kropinski
1Laboratory of Gene Technology (LoGT), Katholieke Universiteit Leuven, Kasteelpark Arenberg 21 bus 2462, B-3001 Leuven, Belgium.
Virology Journal
|March 25, 2011
Summary
Minor genomic changes in Pseudomonas aeruginosa bacteriophages (ϕKMV) lead to significant variations in infection cycles and host range. These differences are crucial for understanding phage therapy applications.
Area of Science:
- Microbiology
- Genetics
- Virology
Background:
- Horizontal gene transfer is key in bacteriophage evolution, but vertical evolution also shapes lytic phage genomes.
- Investigated the impact of minor genomic deletions and insertions on phage properties.
Purpose of the Study:
- To analyze the phenotypic and serological variations among different isolates of Pseudomonas aeruginosa bacteriophage ϕKMV.
- To understand how small genomic alterations influence phage behavior and host interactions.
Main Methods:
- Sequencing of ten ϕKMV bacteriophage isolates.
- Comparative analysis of genomic sequences (42-43 kb) and terminal repeats.
- Phenotypic characterization including latent period, lysis efficiency, and host range determination.
- Serological testing against specific antisera.
Main Results:
- Nearly identical genomes (83-97% similarity) showed significant variation in latent periods (21-28 min) and lysis efficiency (5-58% of 107 clinical strains).
- Phages with identical tail structures exhibited diverse host spectra.
- Point mutations in tail and spike proteins enabled evasion of specific antiserum neutralization.
Conclusions:
- Despite high genomic similarity, ϕKMV phages display substantial phenotypic diversity.
- Variations in host spectrum and immune evasion suggest potential for phage therapy applications.
- Genomic microevolution significantly impacts bacteriophage efficacy and host interaction.
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