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Updated: Jul 23, 2026
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TransFLP — A Method to Genetically Modify Vibrio cholerae Based on Natural Transformation and FLP-recombination
Published on: October 8, 2012
Transposon-facilitated recombination in Vibrio cholerae
Molecular & General Genetics : MGG
|February 16, 1979
Summary
Transposon-facilitated recombination (Tfr) donors were created by inserting the ampicillin transposon (Tn1) into Vibrio cholerae. These Tfr donors efficiently transferred chromosomal genes, enabling precise mapping of bacterial genes using Tn1.
Area of Science:
- Microbiology
- Molecular Biology
- Genetics
Background:
- High-frequency gene transfer in Vibrio cholerae is crucial for genetic studies.
- Previous methods for constructing donor strains had limitations in efficiency and precision.
Purpose of the Study:
- To develop a novel method for constructing highly efficient Vibrio cholerae donor strains for genetic analysis.
- To utilize transposon-facilitated recombination (Tfr) for precise mapping of chromosomal genes.
Main Methods:
- Constructing Vibrio cholerae donor strains by integrating the ampicillin transposon (Tn1) into both a conjugative plasmid (P) and the bacterial chromosome.
- Employing a deleted P::Tn1 vector for chromosomal Tn1 transposition, followed by elimination of helper plasmids.
- Utilizing thermosensitive plasmids for efficient plasmid curing and selection of stable donor strains.
- Characterizing Tfr donors by measuring gene transfer frequencies and genetic linkage to determine Tn1 chromosomal insertion sites.
Main Results:
- Successfully constructed Tfr donors capable of high-frequency chromosomal gene transfer.
- Demonstrated that chromosomally inserted Tn1 copies serve as origins for gene transfer.
- Established genetic linkage between the ampicillin resistance gene (amp) and specific chromosomal locations.
- Showed that the direction of Tn1 insertion on the plasmid influences chromosomal transfer.
Conclusions:
- Transposon-facilitated recombination offers a powerful and versatile tool for constructing efficient Vibrio cholerae donor strains.
- This method facilitates high-resolution genetic mapping and characterization of Vibrio cholerae genes.
- Tfr donors significantly advance the genetic manipulation and understanding of Vibrio cholerae.
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