Related Experiment Video
Updated: Jun 21, 2026

Isolation and Identification of Waterborne Antibiotic-Resistant Bacteria and Molecular Characterization of their Antibiotic Resistance Genes
Published on: March 3, 2023
Molecular epidemiology of vancomycin-resistant enterococci in Singapore
Tse H Koh1, Beng S Low, Nicholas Leo
1Department of Pathology, Singapore General Hospital, Singapore. koh.tse.hsien@sgh.com.sg
Aims:
To characterise the mechanism of glycopeptide resistance, genetic relatedness, and pathogenicity factors in isolates of vancomycin-resistant enterococci (VRE) in Singapore.
Methods:
A total of 292 Enterococcus faecium and 17 Enterococcus faecalis were isolated from humans, and five E. faecium, two Enterococcus durans, two Enterococcus flavescens, one Enterococcus casseliflavus, and one Enterococcus gallinarum from chickens. The mechanism of glycopeptide resistance and pathogenicity factors were studied by PCR and the genetic relatedness determined by pulsed-field gel electrophoresis (PFGE), multi-locus variable number tandem repeat analysis (MLVA), and Tn1546 analysis.
Results:
There were five outbreak clones among the vancomycin-resistant E. faecium with one clone predominant. Four of the clones were vanB positive, and only one clone carried vanA. All outbreak clones were esp gene positive. Sporadic human isolates and chicken isolates were vanA positive and did not contain any pathogenicity genes. The situation was reversed in vancomycin-resistant E. faecalis where almost all isolates were vanA positive.
Conclusions:
Most VRE in Singapore is hospital associated with a small number of clones of esp-positive vanB E. faecium responsible for the majority of isolates.
Related Concept Videos
Clinical Significance of Antibiotic Resistance
Mechanism of Antibiotic Resistance in MRSA
Development of Antibiotic Resistance
Bacterial Gastroenteritis
Antimicrobial Effectiveness
