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Bacterial 'Grounded' Prophages: Hotspots for Genetic Renovation and Innovation.
Bhaskar Chandra Mohan Ramisetty1, Pavithra Anantharaman Sudhakari1
1Laboratory of Molecular Biology and Evolution, School of Chemical and Biotechnology, SASTRA Deemed University, Thanjavur, India.
Frontiers in Genetics
|February 28, 2019
Summary
Temperate bacteriophages, when mutated to
Area of Science:
- Microbial genetics
- Bacteriophage biology
- Evolutionary microbiology
Background:
- Bacterial genomes evolve through mutation and gene acquisition, with selection favoring adaptive variants.
- Temperate bacteriophages influence bacterial populations via lytic and lysogenic cycles, offering immunity but risking lysis.
- Prophage 'grounding' via mutation prevents lysis and confers advantages, driving bacterial evolution.
Purpose of the Study:
- To investigate the evolutionary role of 'grounded' prophages in bacterial genome evolution.
- To explore how grounded prophages act as 'genetic buffer zones' and hotspots for gene transfer.
- To exemplify the significance of grounded prophages in bacterial ecology and evolution using *E. coli*.
Main Methods:
- Analysis of bacterial genome plasticity and adaptation mechanisms.
- Study of temperate bacteriophage lytic and lysogenic cycles.
- Sequence analysis of characterized *E. coli* prophages to identify grounded prophage roles.
Main Results:
- Lysogeny provides a selective advantage, but grounded prophages offer enhanced benefits by preventing lysis.
- Grounded prophages facilitate genetic variations like inversions, deletions, and insertions.
- These prophages act as hotspots for horizontal gene transfer, integrating genes for stress tolerance, antimicrobial resistance, and new metabolic pathways.
Conclusions:
- Grounded prophages significantly accelerate bacterial genome evolution by increasing variation frequency and diversity.
- They serve as crucial sites for the generation of new genetic information (*de novo* genesis).
- Temperate prophages, particularly in their grounded state, are key drivers of bacterial evolution and genetic innovation.
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