Complex Class 1 Integron in a Clinical Strain From Vietnam Carrying Both and .

The co-production of MCR and carbapenemase in has been previously reported. Here, we describe a clinical strain of from Vietnam carrying both and . Whole-genome sequencing showed that the genome of this strain consists of a 4,975,832-bp chromosome and four plasmids. The and genes are located on IncI2 and IncA/C2-type plasmids, respectively. Genetic analysis revealed the presence of a multidrug-resistant region with the structure of a novel complex class 1 integron including a class 1 integron region bearing two 5' conserved segments and one 3' conserved segment and two complete structures of IS. The complex integron contains aminoglycoside resistance genes , , , , and , quinolone resistance gene , extended-spectrum β-lactamase gene , and a Tn-like transposon bearing . In addition, the ---- gene cassette array belonging to the -type integron was also identified, but the region found downstream of the gene cassette array is the IS--IS element instead of the gene. The results further support that isolates co-harboring and are widely being distributed. The structural characteristics of the complex integron reveal that IS elements play an important role in the mobilization of and the development of multidrug-resistant regions.