Genetic Context of optrA and poxtA in Florfenicol-Resistant Enterococci Isolated from Flowing Surface Water in Switzerland.

Linezolid is an important last-resort antibiotic for the treatment of multidrug-resistant enterococci. The aim of this study was to further characterize the genetic context of optrA and poxtA in 10 florfenicol-resistant enterococci isolated from flowing surface water. In most genomes, optrA and poxtA were embedded in transposition units integrated into plasmids or into the chromosomal radC . For the first time, a chromosomally integrated optrA in an Enterococcus raffinosus isolate is described.