Related Experiment Video
Updated: Dec 13, 2025
Super-Resolution Imaging of Bacterial Secreted Proteins Using Genetic Code Expansion
Published on: February 10, 2023
Characterization of pTS14, an IncF2:A1:B1 Plasmid Carrying tet(M) in a Salmonella enterica Isolate
Ying-Ying Liu1, Xiao-Kang Liu1, Xiao-Die Cui1
1College of Animal Husbandry and Veterinary Science, Henan Agricultural University, Zhengzhou, China.
Abstract:
The objective of this study was to explore the genetic and biological features of the tet(M)-harboring plasmid pTS14 in Salmonella enterica strain S14 isolated from a chicken fecal sample. Plasmid pTS14 was identified by conjugation, S1-pulsed-field gel electrophoresis (PFGE), Southern hybridization, and plasmid sequencing. The biological characteristics of pTS14 were assessed via stability, growth kinetics, and starvation survival experiments. Strain S14, belonging to ST3007, harbored a 119-kb tet(M)-bearing IncF2:A1:B1 conjugative plasmid pTS14. The plasmid pTS14 contained a novel transposon Tn6709 with the genetic structure IS26-tnpA1-tnpA2-Δorf13-LP-tet(M)-tnpX-ΔtnpR-IS26, and the resistance genes tet(B), tet(D), strAB, sul2, and bla TEM-1b. In addition, pTS14 was found to be highly stable in the recipient strain E. coli J53. The transconjugant TS14 exhibited a higher survival ratio than E. coli J53 under permanent starvation-induced stress. The tet(M)-bearing IncF2 epidemic plasmid lineage may accelerate the dissemination of tet(M) and other genes by coselection, which could constitute a potentially serious threat to clinical treatment regimens.
Insights
A novel 119-kb plasmid, pTS14, carrying the tetracycline resistance gene tet(M) was identified in Salmonella enterica. This highly stable plasmid also harbors additional resistance genes and enhances bacterial survival under stress, posing a clinical threat.
Area of Science:
- Microbiology
- Genetics
- Molecular Biology
Background:
- Antimicrobial resistance is a growing global health concern.
- Plasmids are key vehicles for the dissemination of antibiotic resistance genes.
- Salmonella enterica is an important foodborne pathogen.
Purpose of the Study:
- To characterize the genetic and biological features of the tet(M)-harboring plasmid pTS14 in Salmonella enterica strain S14.
- To assess the stability and survival capabilities conferred by plasmid pTS14.
- To evaluate the potential threat posed by this plasmid lineage.
Main Methods:
- Plasmid identification using conjugation, pulsed-field gel electrophoresis (PFGE), and Southern hybridization.
- Complete plasmid sequencing to determine genetic content.
- Biological assessments including stability, growth kinetics, and starvation survival experiments.
Main Results:
- A 119-kb IncF2:A1:B1 conjugative plasmid, pTS14, carrying tet(M) was identified in Salmonella enterica ST3007.
- Plasmid pTS14 harbors a novel transposon Tn6709 and multiple resistance genes: tet(B), tet(D), strAB, sul2, and blaTEM-1b.
- pTS14 demonstrated high stability in E. coli J53 and enhanced transconjugant survival under starvation stress.
Conclusions:
- The tet(M)-bearing IncF2 epidemic plasmid lineage can facilitate the spread of tet(M) and other resistance genes through coselection.
- Plasmid pTS14 represents a significant threat to clinical treatment regimens due to its stability and resistance gene content.
- Further research is needed to understand the full epidemiological impact of such plasmids.
