Characterization of a transferable plasmid-borne mcr-1 in a colistin resistant Shigella flexneri isolate.

Since its initial discovery in an isolate from China, has also been detected in and , and is rarely reported in other Enterobacteriaceae. Here, we report the isolation and identification of a strain harboring from stool samples in a pig farm in China from 2009. The minimum inhibitory concentration (MIC) to colistin of the isolate is 4 μg/mL. Conjugation assays showed the donor strain has functional and transferable colistin resistance. Sequencing revealed that was present on a putative composite transposon flanked by inverted repeats of IS There are four species of , is the most frequently isolated species in Low and Middle Income Countries (LMICs). In this study, we report a functional, transferable, plasmid mediated in We have shown is located on a novel composite transposon which is flanked by inverted repeats of IS The host strain is multi-drug resistant and this multidrug resistance is also transferable. The finding of functional in ; a human associated Enterobacteriaceae is a cause for concern as infections due to are the main infections in most Low and Middle Income Countries. [Abstract copyright: Copyright © 2018 Liang et al.]