Related Experiment Video
Updated: Aug 4, 2026

Testing the Role of Multicopy Plasmids in the Evolution of Antibiotic Resistance
Published on: May 2, 2018
Long-term carriage and evolution of VREfmLong-term carriage and evolution of vancomycin-resistant Enterococcus
Maja Johanne Søndergaard Knudsen1, Jose Alfredo Samaniego Castruita1, Sarah Mollerup1
1Department of Clinical Microbiology, Copenhagen University Hospital-Amager and Hvidovre, Hvidovre, Denmark.
Objectives:
To determine if vancomycin-resistant Enterococcus faecium (VREfm) carriers carry the same VREfm clone after a minimum follow-up of 365 days. For those carrying the same clone, we investigated the genomic evolution per year per genome.
Methods:
We used WGS results to assign VREfm clones to each isolate and determine clone shifts. Finally, we calculated distance in core-genome MLST alleles, and the number of SNPs between consecutive VREfm isolates from patients carrying the same VREfm clone.
Results:
In total, 44.2% of patients carried the same VREfm clone, and the genomic evolution was 1.8 alleles and 2.6 SNPs per genome per year.
Conclusions:
In our population of long-term carriers, we calculated a molecular clock of 2.6 SNPs.
More Related Videos
Related Concept Videos
Development of Antibiotic Resistance
Modern Molecular Taxonomy
Evolution of New Traits in Microbes
Evolution of Microbial Genome
Mechanism of Antibiotic Resistance in MRSA
Clinical Significance of Antibiotic Resistance

