Abstract
To investigate the capacities of persistence and dissemination of blaNDM-5 within Escherichiacoli and in aquatic environment, we characterized E. coli (sequence type 636) strains B26 and B28isolated one month apart from the same urban river in Montpellier, France. The two isolates carried apTsB26 plasmid, which sized 45,495 Kb, harbored blaNDM-5 gene and belonged to IncX-3 incompatibilitygroup. pTsB26 was conjugative in vitro at high frequency, it was highly stable after 400 generationsand it exerted no fitness cost on its host. blaNDM-5harboring plasmids are widely dispersed in E. coliall around the world, with no lineage specialization. The genomic comparison between B26 and B28stated that the two isolates probably originated from the same clone, suggesting the persistence ofpTsB26 in an E. coli host in aquatic environment.