title: Enterobacter cloacae Complex Isolates HarboringblaNMC-AorblaIMI-Type Class A Carbapenemase Genes on Novel Chromosomal Integrative Elements and Plasmids.
abstract: Carbapenem-resistantEnterobacter cloacaecomplex isolates submitted to a reference laboratory from 2010 to 2015 were screened by PCR for seven common carbapenemase gene groups, namely, KPC, NDM, OXA-48, VIM, IMP, GES, and NMC-A/IMI. Nineteen of the submitted isolates (1.7%) were found to harbor Ambler class AblaNMC-AorblaIMI-type carbapenemases. All 19 isolates were resistant to at least one carbapenem but susceptible to aminoglycosides, trimethoprim-sulfamethoxazole, tigecycline, and ciprofloxacin. Most isolates (17/19) gave positive results with the Carba-NP test for phenotypic carbapenemase detection. Isolates were genetically diverse by pulsed-field gel electrophoresis macrorestriction analysis, multilocus sequence typing, andhsp60gene analysis. The genes were found in variousEnterobacter cloacaecomplex species; however,blaNMC-Awas highly associated withEnterobacter ludwigiiWhole-genome sequencing and bioinformatics analysis revealed that all NMC-A (n= 10), IMI-1 (n= 5), and IMI-9 (n= 2) producers harbored the carbapenemase gene on EludIMEX-1-like integrative mobile elements (EcloIMEXs) located in the identical chromosomal locus. Two novel genes,blaIMI-5andblaIMI-6, were harbored on different IncFII-type plasmids.Enterobacter cloacaecomplex isolates harboringblaNMC-A/IMI-type carbapenemases are relatively rare in Canada. Though mostly found integrated into the chromosome, some variants are located on plasmids that may enhance their mobility potential.
authors.affiliation: National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada.
authors.forename: David A
authors.initials: DA
authors.lastname: Boyd
authors.affiliation: National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada.
authors.forename: Laura F
authors.initials: LF
authors.lastname: Mataseje
authors.affiliation: Queen Elizabeth II Health Sciences Centre, Dalhousie University, Halifax, Nova Scotia, Canada.
authors.forename: Ross
authors.initials: R
authors.lastname: Davidson
authors.affiliation: Division of Microbiology, Pathology and Laboratory Medicine, London Health Sciences Centre, London, Ontario, Canada.
authors.forename: Johannes A
authors.initials: JA
authors.lastname: Delport
authors.affiliation: Provincial Laboratory of Alberta, Alberta Health Services, Edmonton, Alberta, Canada.
authors.forename: Jeff
authors.initials: J
authors.lastname: Fuller
authors.affiliation: British Columbia Public Health Microbiology and Reference Laboratory, Provincial Health Services Authority Laboratories, Vancouver, British Columbia, Canada.
authors.forename: Linda
authors.initials: L
authors.lastname: Hoang
authors.affiliation: Laboratoire de Santé Publique du Québec, Sainte-Anne-de-Bellevue, Quebec, Canada.
authors.forename: Brigitte
authors.initials: B
authors.lastname: Lefebvre
authors.affiliation: Saskatchewan Disease Control Laboratory, Regina, Saskatchewan, Canada.
authors.forename: Paul N
authors.initials: PN
authors.lastname: Levett
authors.affiliation: Pathology and Laboratory Medicine, Vancouver General Hospital, Vancouver, British Columbia, Canada.
authors.forename: Diane L
authors.initials: DL
authors.lastname: Roscoe
authors.affiliation: Department of Microbiology, Mount Sinai Hospital, Toronto, Ontario, Canada.
authors.forename: Barbara M
authors.initials: BM
authors.lastname: Willey
authors.affiliation: National Microbiology Laboratory, Public Health Agency of Canada, Winnipeg, Manitoba, Canada michael.mulvey@phac-aspc.gc.ca.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Mulvey
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000235:genetics*; D015373:Bacterial Typing Techniques; D002170:Canada; D015780:Carbapenems / Q000494:pharmacology*; D018834:Chaperonin 60 / Q000235:genetics; D004251:DNA Transposable Elements / Q000235:genetics*; D016972:Enterobacter cloacae / Q000187:drug effects / Q000235:genetics* / Q000302:isolation & purification; D005260:Female; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D058885:Multilocus Sequence Typing; D010802:Phylogeny; D010957:Plasmids / Q000235:genetics*; D000073336:Whole Genome Sequencing; D001618:beta-Lactamases / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D015780:Carbapenems; D018834:Chaperonin 60; D004251:DNA Transposable Elements; C088657:NmcA protein, Enterobacter cloacae; D001618:beta-Lactamases; C063912:carbapenemase
keywords: carbapenemase