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The complete nucleotide sequences of three multidrug resistance (MDR) IncA/C-like plasmids from Enterobacteriaceae isolates carrying the VIM-type carbapenemase-encoding integrons In4863 (bla(VIM-19)-aacA7-dfrA1-Delta aadA1-smr2) or In4873 (bla(VIM-1)-aacA7-dfrA1-Delta aadA1-smr2) were determined, which are the first In416-like elements identified in Greece. Plasmids pKP-Gr642 and pKP-Gr8143 were from Klebsiella pneumoniae ST383 isolates, whereas plasmid pEcl-Gr4873 was from an Enterobacter cloacae ST88 isolate. Sequencing showed that pKP-Gr642 (162 787 bp) and pKP-Gr8143 (154 395 bp) consisted of the type 1 IncA/C-2 conserved backbone, the blaCMY-2-like gene-containing region, and the ARI-B (with the sul2 gene) and ARI-A (with a class 1 integron) resistance islands, like the plasmid pUMNK88-161 from the USA. The third plasmid, pEcl-Gr4873 (153 958 bp), exhibited extensive similarity with the type 2 IncA/C-2 plasmid pR55 from France. pEcl-Gr4873 carried only one resistance island of a hybrid transposon structure inserted in a different location to ARI-A in type 1 A/C-2 plasmids. In all three plasmids, the In416-like integrons In4863 or In4873 were identified within non-identical class II transposon structures. All three In416-like-carrying regions presented significant similarities with the MDR region of the IncA/C-2 plasmid pCC416 from Italy, carrying the prototype In416 integron (bla(VIM-4)-aacA7-dfrA1-Delta aadA1-smr2). These findings provided the basis for speculations regarding the evolution of IncA/C-2 plasmids with In416-like integrons, and confirmed the rapid evolution of some IncA/C-2 plasmid lineages. Considering the broad host range of IncA/C-2 molecules, it seems that pKP-Gr642, pKP-Gr8143 and pEcl-Gr4873 plasmids might support the diffusion of In416-like integrons among Enterobacteriaceae. (C) 2015 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved. |
