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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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An easily modifiable conjugative plasmid for studying horizontal gene transfer.
Qinqin Wang1, Asmus Kalckar Olesen1, Lorrie Maccario1
1Section of Microbiology, Department of Biology, University of Copenhagen, 2100 Copenhagen, Denmark.
Plasmid
|September 13, 2022
Summary
Researchers developed a new conjugative plasmid model for studying bacterial horizontal gene transfer. This tool efficiently inserts genes, aiding research into antibiotic resistance spread.
Area of Science:
- Microbiology and Molecular Biology
- Bacterial Genetics and Evolution
Background:
- Horizontal gene transfer (HGT) is a key driver of bacterial evolution and the spread of antibiotic resistance.
- Conjugative plasmids are major mediators of HGT, but suitable genetic models for studying this process are lacking.
- Efficient methods for genetically modifying plasmids are needed to investigate HGT mechanisms.
Purpose of the Study:
- To develop a versatile conjugative plasmid model for efficient gene insertion.
- To facilitate the study of horizontal gene transfer and antibiotic resistance gene dissemination.
Main Methods:
- Engineered the broad-host-range IncP-1 plasmid pKJK5 by introducing a non-disruptive attTn7 site.
- Constructed modified versions: one with a reduced transfer rate and a non-conjugative variant.
- Utilized the Tn7 transposition system for efficient, single-step insertion of gene cassettes.
Main Results:
- Successfully created pKJK5-attTn7, enabling convenient insertion of genes of interest.
- Demonstrated efficacy by inserting superfolder green fluorescent protein (sfGFP) and seven different beta-lactamase genes.
- The attTn7 site allows for the introduction of larger genetic fragments with high success rates.
Conclusions:
- The developed pKJK5-attTn7 plasmid system provides an efficient and convenient tool for genetic manipulation.
- This model will significantly advance research into bacterial HGT and the spread of antimicrobial resistance.
- The system's flexibility supports the study of various gene insertions, including reporter and resistance genes.
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