First report of mobile tigecycline resistance gene tet(X4)-harbouring multidrug-resistant Escherichia coli from wastewater in Norway

Abstract

The mobile tigecycline resistance gene tet(X4), conferring resistance to all tetracyclines, is largely reported from China, however the global spread of such a novel resistance mechanism is a concern for preserving the efficacy of these last-resort antibiotics. The aim of our study was to determine the genetic basis of resistance in a tigecycline-resistant Escherichia coli strain (2-326) isolated from sewage in Bergen, Norway, using whole-genome sequencing (WGS).