Polymorphism Existence of Mobile Tigecycline Resistance Gene tet(X4) in Escherichia coli

Characteristics of the novel ColE2-like plasmid p16EC-9K bearing tet(X4) and the tandem structure of multicopy of ISCR2-tet(X4). Arrows indicate genes and their directions. Regions in gray represent two linked areas with high sequence similarity. (A) Linear alignment of the original plasmid reads generated by MinION sequencing and the final polished sequences generated by HiSeq sequencing. A schematic of p16EC-9K is shown between the linear sequences. (B) Structure of the tandem tet(X4)-ISCR2 segment and diagram showing the various copy number arrangements detected in the sequencing reads.