Complete Nucleotide Sequence of a Novel Plasmid Bearing the High-Level Tigecycline Resistance Gene tet(X4)

We reported the complete nucleotide sequence of a tet (X4)-carrying plasmid, pSTB20-1T, from a tigecycline-resistant Escherichia coli isolate in China. Sequence analysis indicated that pSTB20-1T contains a hybrid plasmid backbone and a tet (X4)-containing multidrug resistance region, likely originated through recombination of multiple plasmids. tet (X4) was flanked by two IS CR2 , which may be responsible for tet (X4) mobilization.