AUTHOR=Zurfluh Katrin , Jakobi Gianna , Stephan Roger , Hächler Herbert , Nüesch-Inderbinen Magdalena 

TITLE=Replicon typing of plasmids carrying blaCTX-M-1 in Enterobacteriaceae of animal, environmental and human origin

JOURNAL=Frontiers in Microbiology

VOLUME=Volume 5 - 2014

YEAR=2014

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2014.00555

DOI=10.3389/fmicb.2014.00555

ISSN=1664-302X

ABSTRACT=Objectives: The aim of this work was to determine the plasmid replicon profiles of a collection of blaCTX-M-1-positive enterobacterial strains. The isolates originated from chicken in the production pyramid, healthy food-producing animals at slaughter (chicken, calves and pigs), chicken retail meat, environmental isolates originating from water bodies, and isolates from humans. A selection of IncI and IncN plasmids were characterized by multilocus sequence typing in order to determine their epidemiological relatedness. 
Methods: Transconjugants of 74 blaCTX-M-1-positive isolates were analysed by PCR-based replicon typing and by PCR-based plasmid multilocus sequence typing.
Results: The incompatibility groups detected among the blaCTX-M-1-harboring plasmids included IncI1, IncN, IncHI1B, IncF, IncFIIS, IncFIB and IncB/O, with plasmid lineage IncI1/ST3 predominating in isolates from chicken and from humans. Lineage IncN/ST1 was detected mainly in isolates from pigs. For the first time, blaCTX-M-1 genes encoded on IncHI1 plasmids were detected in isolates from cattle and from water bodies.
Conclusions: This study identifies plasmid lineages that are contributing to the dissemination of blaCTX-M-1 genes in the food chain, the environment, and humans.