Enterobacter cloacae Complex Sequence Type 171 Isolates Expressing KPC-4 Carbapenemase Recovered from Canine Patients in Ohio

Abstract

Companion animals are likely relevant in the transmission of antimicrobial-resistant bacteria. Enterobacter xiangfangensis sequence type 171 (ST171), a clone that has been implicated in clusters of infections in humans, was isolated from two dogs with clinical disease in Ohio. The canine isolates contained IncHI2 plasmids encoding bla_KPC-4 Whole-genome sequencing was used to put the canine isolates in phylogenetic context with available human ST171 sequences, as well as to characterize their bla_KPC-4 plasmids.

Keywords: antibiotic resistance; carbapenemase; plasmid-mediated resistance; veterinary microbiology.

FIG 1

IncHI2 plasmids (pOSUVMCKPC4-2 [violet] and pOSUVMCKPC4-1 [blue]) isolated from E. xiangfangensis ST171 sourced from dogs. The outer ring denotes the location and orientation of genes. Subplasmidic mobile-element-associated sequences are indicated in orange and resistance genes in red. Plasmid transfer genes are indicated in green. In524 inverted region is indicated in gray, and IS3 sequences are in black.

FIG 2

Schematic structure of Tn4401b containing bla_KPC-4 present on large IncH12 plasmids in E. xiangfangensis ST171 isolates recovered from two canine patients of The Ohio State University Veterinary Medical Center in 2016. Genes and their corresponding transcription orientation are indicated by colored horizontal arrows. Corresponding insertion sequences (IS) that encode transposons are indicated at the top of the figure with a narrow blue line. Black triangles indicate inverted repeat right and left sequences associated with the ISKpn6 and ISKpn7 elements. Flanking parallelograms represent the two inverted repeat sequences associated with Tn4401 structures.

FIG 3

Heatmap of plasmids among bla_KPC-4 bearing E. xiangfangensis ST171, with additional KPC-2- and KPC-3-containing ST171 isolates included as references. Left, core SNP phylogenetic tree generated by RAxML; center, metadata, including host, isolation location, year, Tn4401 isoform, and KPC allele; right, plasmid composition is illustrated by showing the BLASTn matches to each E. xiangfangensis ST171 genome across all of the genes on the pOSUVMCKPC4-2 plasmid.