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09:23
Understanding the Impact of Temperate Bacteriophages on Their Lysogens Through Transcriptomics
Published on: January 5, 2024
Comparative genomics of Shiga toxin encoding bacteriophages
Darren L Smith1, David J Rooks, Paul C M Fogg
1Microbiology Research Group, Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool, L69 7ZB, UK.
BMC Genomics
|July 18, 2012
Summary
Shiga toxin (Stx) phages, like Ф24B, spread Stx toxin genes. Ф24B’s unique genome, with heterogeneous regions, suggests mosaic evolution driven by recombination, impacting Stx phage variants and shigatoxigenic potential.
Area of Science:
- Microbiology
- Genomics
- Virology
Background:
- Shiga toxin (Stx) bacteriophages are key drivers of Stx gene dissemination.
- Stx phages contribute to severe human diseases, with Stx toxin as a critical virulence factor.
- The Stx-bacteriophage Ф24B exhibits unusual high-frequency multiple infections of bacterial hosts.
Purpose of the Study:
- To determine the genomic content and context of the Stx-bacteriophage Ф24B.
- To compare Ф24B to other lambdoid Stx phages to understand its unique biology.
- To investigate factors controlling Ф24B's unusual infection behavior and its presence in other Stx phages.
Main Methods:
- Genome sequencing and annotation of the Stx2-encoding phage Ф24B.
- Comparative genomics using the Circos tool to compare Ф24B with other Stx phages and the lambda phage.
- Multi-loci comparison system utilizing PCR.
Main Results:
- The Ф24B genome shares general features with other Stx phages from Enterohaemorrhagic Escherichia coli (EHEC).
- Significant regions of genomic heterogeneity were identified in Ф24B, impacting its biology and behavior.
- Comparative analysis revealed Ф24B's unique genomic characteristics compared to archetypal lambdoid phages.
Conclusions:
- Stx phages are mosaic genetic structures.
- Recombination events between host bacteria, phages, and their remnants drive Stx phage evolution.
- These evolutionary processes will continue to shape Stx phage variants and spread shigatoxigenic potential.
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