Complete sequences of a novel blaNDM-1-harbouring plasmid from Providencia rettgeri and an FII-type plasmid from Klebsiella pneumoniae identified in Canada

Results: Both clinical isolates were resistant to allb-lactams, carbapenems, aminoglycosides, ciprofloxacin and trimethoprim/sulfamethoxazole, and susceptible to tigecycline. Plasmid pPrY2001 (113295 bp) was isolated from PR. It did not show significant homology to any known plasmid backbone and contained a truncated repA and novel repB. Two blaNDM-1-harbouring plasmids from Acinetobacter lwoffii (JQ001791 and JQ060896) shared 100% similarity to a 15 kb region that contained blaNDM-1. pPrY2001 also contained a type II toxin/antitoxin system. pKp11-42 (146695 bp) was isolated from KP. It contained multiple repA genes. The plasmid backbone had the highest homology to the IncFIIk plasmid type (51% coverage, 100% nucleotide identity). The blaNDM-1 region was unique in that it was flanked upstream by IS3000 and downstream by a novel transposon designated Tn6229 .p Kp11-42 also contained a number of mutagenesis and plasmid stability proteins. Conclusions: pPrY2001 differed from all known plasmids due to its novel backbone and repB .p Kp11-42 was similar to IncFIIk plasmids and contained a number of genes that aid in plasmid persistence.