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Detection of Horizontal Gene Transfer Mediated by Natural Conjugative Plasmids in E. coli
Published on: March 24, 2023
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Bacteria from natural populations transfer plasmids mostly towards their kin
Tatiana Dimitriu1, Lauren Marchant1, Angus Buckling1
1Department of Biosciences, University of Exeter , Penryn Campus, Cornwall TR10 9FE , UK.
Proceedings. Biological Sciences
|June 27, 2019
Summary
Bacterial plasmid transfer is biased towards genetically similar strains, particularly clone-mates. This suggests that defense mechanisms in recipient bacteria limit plasmid spread, favoring kin interactions and potential coevolution.
Area of Science:
- Microbial Ecology
- Bacterial Genetics
- Evolutionary Biology
Background:
- Plasmids are crucial for microbial ecology and evolution.
- Understanding plasmid transfer rates and their determinants is limited.
- Interactions between donor hosts and recipients require further study.
Purpose of the Study:
- Investigate the role of genetic similarity in plasmid transfer among naturally occurring Escherichia coli isolates.
- Quantify variability in plasmid donation and reception.
- Identify factors influencing plasmid transfer bias.
Main Methods:
- Utilized naturally co-occurring Escherichia coli isolates.
- Assessed donation and reception of two plasmids (R1 and RP4).
- Analyzed transfer rates in relation to genetic similarity and recipient defense systems.
Main Results:
- Observed extensive variability (over five orders of magnitude) in plasmid transfer rates.
- Demonstrated strong bias towards clone-mates for plasmid transfer.
- Found no correlation between genetic distance and transfer when isolates were not clone-mates.
- Identified functional restriction-modification systems in recipients as a key factor limiting transfer.
Conclusions:
- Genetic similarity, particularly within clone-mates, significantly influences plasmid transfer in Escherichia coli.
- Recipient defense systems, like restriction-modification systems, create a bias towards kin.
- This kin-biased transfer can promote coevolutionary dynamics, potentially leading to mutualism between plasmids and hosts.
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