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Updated: Aug 14, 2026
09:23
Understanding the Impact of Temperate Bacteriophages on Their Lysogens Through Transcriptomics
Published on: January 5, 2024
Widespread genetic exchange among terrestrial bacteriophages
Olin K Silander1, Daniel M Weinreich, Kevin M Wright
1Department of Biological Sciences, University of California at San Diego, 9500 Gilman Drive, La Jolla, CA 92093, USA.
Summary
Genetic exchange in bacteriophages is surprisingly high. Wild populations of Cystoviridae phages show extensive genetic reassortment between segments, suggesting a highly sexual population despite significant genomic divergence.
Area of Science:
- Virology
- Microbial Ecology
- Population Genetics
Background:
- Bacteriophages are the most abundant biological entities globally.
- The genetic structure of bacteriophage populations remains largely uncharacterized.
- Cystoviridae phages possess a unique dsRNA genome segmented into three parts.
Purpose of the Study:
- To investigate the genetic structure and population dynamics of wild bacteriophage populations.
- To analyze recombination and reassortment rates in Cystoviridae phages.
- To assess the genetic exchange mechanisms in these abundant viral entities.
Main Methods:
- Biogeographical analysis of 25 novel Cystoviridae bacteriophages.
- Linkage disequilibrium (LD) analysis within and between genome segments.
- Comparison of genetic exchange patterns with mutation rates and nucleotide divergence.
Main Results:
- No significant evidence of intrasegment recombination was found in wild populations.
- Extensive linkage disequilibrium between segments indicates frequent genetic reassortment.
- Absence of LD suggests a highly sexual population, even with high nucleotide divergence (>50%) between segments.
Conclusions:
- Wild bacteriophage populations exhibit a high rate of genetic exchange, challenging previous assumptions.
- Frequent reassortment between highly divergent segments points to a population behaving as if completely sexual.
- The findings have implications for understanding viral evolution and applying the biological species concept to viruses.
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