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Updated: Feb 19, 2026
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Author Spotlight: Advancements in Understanding and Combatting Shigella Infections
Published on: February 9, 2024
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Genetic Exchanges Shape the Evolutionary Diversification Among Shigella phages.
Joyeeta Chatterjee1, Pratanu Kayet1, Manisha Ghosh1
1Division of Bioinformatics, ICMR-National Institute for Research in Bacterial Infections, 700010, Kolkata, India.
Journal of Molecular Evolution
|February 17, 2026
Summary
Shigella bacteriophages carry genes for virulence and antibiotic resistance. Horizontal gene transfer (HGT) drives bacterial evolution, and understanding phage genomics is key to combating infectious diseases.
Area of Science:
- Microbiology and Genomics
- Bacterial Evolution and Genetics
Background:
- Shigella bacteria cause infectious diarrhea (shigellosis).
- Bacteriophages, viruses that infect bacteria, play a crucial role in bacterial evolution by transferring genes.
- Mobile genetic elements (MGEs) and horizontal gene transfer (HGT) are significant drivers of bacterial virulence and antibiotic resistance.
Purpose of the Study:
- To conduct a comprehensive genomic analysis of Shigella bacteriophages.
- To investigate the role of HGT in shaping phage genomes and bacterial fitness.
- To understand evolutionary constraints and host-range expansion in Shigella phages.
Main Methods:
- Identification and application of the weighted gene repertoire relatedness (wGRR) metric.
- Association of genetic exchanges with infecting host species and phage lifestyles.
- Analysis of the impact of HGT on gene GC content and amino acid usage.
Main Results:
- HGT influences gene GC content and amino acid usage in Shigella phages.
- Host-range expansion was observed in Shigella phages.
- Shigella phages with dissimilar lifestyles show limited propensity for genetic transfer.
Conclusions:
- Genomic analysis provides insights into MGEs and HGTs in Shigella phages.
- HGT significantly impacts phage evolution, bacterial infectivity, and host range.
- Understanding these mechanisms can enhance phage therapy applications against antibiotic-resistant bacteria.
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