A Silenced vanA Gene Cluster on a Transferable Plasmid Caused an Outbreak of Vancomycin-Variable Enterococci.

ABSTRACT: We report an outbreak of vancomycin-variable vanA(+) enterococci (VVE) able to escape phenotypic detection by current guidelines and demonstrate the molecular mechanisms for in vivo switching into vancomycin resistance and horizontal spread of the vanA cluster. Forty-eight vanA(+) Enterococcus faecium isolates and one Enterococcus faecalis isolate were analyzed for clonality with pulsed-field gel electrophoresis (PFGE), and their vanA gene cluster compositions were assessed by PCR and whole-genome sequencing of six isolates. The susceptible VVE strains were cultivated in brain heart infusion broth containing vancomycin at 8 μg/ml for in vitro development of resistant VVE. The transcription profiles of susceptible VVE and their resistant revertants were assessed using quantitative reverse t

SUBMITTER: Sivertsen A 

PROVIDER: S-EPMC4914660 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature