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Updated: Oct 4, 2025

Conjugative Mating Assays for Sequence-specific Analysis of Transfer Proteins Involved in Bacterial Conjugation
10:41

Conjugative Mating Assays for Sequence-specific Analysis of Transfer Proteins Involved in Bacterial Conjugation

Published on: January 4, 2017

14.0K

Recombination events that occur in a poxtA-carrying Enterococcus faecium during the conjugation process

Chunyan Xu1, Nannan Wang1, Dexi Li1

  • 1College of Veterinary Medicine, Henan Agricultural University, Zhengzhou, 450046, P. R. China.

The Journal of Antimicrobial Chemotherapy
|February 9, 2022
PubMed
Abstract

Insights

This study reveals plasmid integration into bacterial chromosomes and the formation of novel mosaic plasmids during conjugation in Enterococcus faecium. These events facilitate the spread of antibiotic resistance genes and drive plasmid evolution.

Area of Science:

  • Microbiology
  • Genetics
  • Molecular Biology

Background:

  • Enterococcus faecium is a significant opportunistic pathogen.
  • Antibiotic resistance in enterococci poses a major public health threat.
  • Understanding plasmid transfer and evolution is crucial for combating resistance.

Purpose of the Study:

  • To investigate the transferability of poxtA-carrying plasmids in Enterococcus faecium.
  • To elucidate the recombination mechanisms during plasmid conjugation.
  • To explore the implications for antibiotic resistance gene dissemination.

Main Methods:

  • Conjugation experiments to assess plasmid transferability.
  • Broth microdilution for Minimum Inhibitory Concentration (MIC) determination.
  • S1-Pulsed Field Gel Electrophoresis (S1-PFGE) and Whole Genome Sequencing (WGS) to analyze recombination.

Main Results:

  • Plasmid pFac90-154 integrated into the recipient E. faecalis JH2-2 chromosome via homologous recombination.
  • IS1216-mediated recombination led to plasmid segment alterations in transconjugants.
  • Plasmid fusion events resulted in the formation of larger mosaic plasmids.

Conclusions:

  • First report of pFac90-154 integration into E. faecalis chromosome via homologous recombination.
  • Genetic rearrangements generated five new plasmid types, forming mosaic plasmids.
  • Conjugation plays a dual role in disseminating resistance genes and driving plasmid evolution.

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