Frontiers in Microbiology (Jan 2020)
Complete Nucleotide Sequence of Plasmids of Two Escherichia coli Strains Carrying blaNDM–5 and blaNDM–5 and blaOXA–181 From the Same Patient
Abstract
Aim of this study was to genetically characterize two carbapenemase-producing Escherichia coli strains obtained from a pediatric patient affected by diarrhea, expressing OXA-181 and/or NDM-5 type enzymes. The above microorganisms were collected in the same Desenzano hospital (Northern Italy) where the blaNDM–5 gene was detected for the first time in Italy 3 years ago. One strain (5P), belonged to sequence type ST405/ST477 (according to Pasture/Oxford schemes) and serotype O102:H6. It was characterized by a 130562 bp multi-replicon plasmid IncFII/IncFIA/IncFIB (pVSI_NDM-5) enclosing two main antibiotic resistance islands: (i) ARI-I, 10030 bp in size, carried genes coding for β-lactam- (blaOXA–1, blaCTX–M–15), fluoroquinolone/aminoglycoside- (aac(6′)-lb-cr) and phenicol- resistance (catB3), (ii) ARI-II, 15326 bp in size, carried genes coding for sulfonamide- (sul1), β-lactam- (blaNDM–5, blaTEM–1B), phenicol- (catB3), trimethoprim- (dfrA17), antiseptic- (qacEΔ1), and aminoglycoside- (aadA5, rmtB) resistance. The other isolate (5M), belonged to sequence type ST2659/ST759 and serotype O50/02:H18, and carried four plasmids: a 153866 bp multi-replicon IncFII/IncFIA/IncFIB (pISV_IncFII_NDM-5), an 89866 bp IncI1 plasmid, a 51480 bp IncX3 plasmid (pISV_IncX3_OXA181), and a 41143 bp IncI plasmid (pISV_IncI_CMY-42). pISV_IncFII_NDM-5 carried two main antibiotic resistance islands: (i) ARI-III, 12220 bp in size, carried genes coding for β-lactam- (blaOXA–1), fluoroquinolone/aminoglycoside- (aac(6′)-lb-cr), tetracycline- (tet(B)) and phenicol- resistance (catB3, catA1), and ii) ARI-IV, 26527 bp in size, carried determinants coding for macrolide- (erm(B), mph(A)), sulfonamide- (sul1), beta-lactam- (blaNDM–5, blaTEM–1B), trimethoprim- (dfrA14, dfrA12), antiseptic- (qacEΔ1), and aminoglycoside- resistance (aadA5). pISV_IncI_CMY-42 harbored the blaCMY–42 gene coding for beta-lactam resistance, pISV_IncX3_OXA181 harbored genes encoding fluoroquinolone- (qnrS1) and beta-lactams- resistance (blaOXA–181). In conclusion, the detection of two different NDM-5 E. coli strains from a pediatric patient with a history of travel to the Far East countries strongly highlight an increasing trend and risk of importation from such areas.
Keywords