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Detection of Horizontal Gene Transfer Mediated by Natural Conjugative Plasmids in E. coli
06:56

Detection of Horizontal Gene Transfer Mediated by Natural Conjugative Plasmids in E. coli

Published on: March 24, 2023

A second large plasmid encodes conjugative transfer and antimicrobial resistance in O119:H2 and some typical O111

Adaobi I Nwaneshiudu1, Tania Mucci, Derek J Pickard

  • 1Department of Biology, Haverford College, 370 Lancaster Avenue, Haverford, PA 19041, USA.

Journal of Bacteriology
|June 19, 2007
PubMed

Insights

A new conjugative transfer system was found on a large multidrug resistance plasmid in enteropathogenic Escherichia coli (EPEC). This overlooked plasmid provides a selective advantage, especially in the antibiotic era.

Area of Science:

  • Microbiology
  • Bacterial genetics
  • Plasmid biology

Background:

  • Enteropathogenic Escherichia coli (EPEC) is a significant cause of diarrheal disease.
  • EPEC pathogenesis is often associated with the EPEC adherence factor (EAF) plasmid.
  • The genetic elements contributing to EPEC virulence and adaptability are not fully understood.

Purpose of the Study:

  • To identify and characterize novel genetic systems in EPEC strains.
  • To investigate the role of plasmids in EPEC antibiotic resistance and transfer.
  • To differentiate between various plasmids present in EPEC strains.

Main Methods:

  • Subtractive hybridization was employed to identify novel DNA sequences.
  • Conjugative transfer experiments were performed to assess plasmid mobility.
  • Gel electrophoresis was used to analyze plasmid profiles of EPEC strains.

Main Results:

  • A novel conjugative transfer system was identified on a large multidrug resistance plasmid in EPEC strain MB80.
  • This plasmid is distinct from the well-characterized EAF plasmid.
  • Similar plasmids were found in other EPEC strains, suggesting a broader role.

Conclusions:

  • A previously overlooked large multidrug resistance plasmid contributes to EPEC.
  • This plasmid confers a selective advantage, particularly in the context of antibiotic use.
  • The comigration of this plasmid with virulence plasmids on gels has led to its underestimation.

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