RT Journal Article SR Electronic(1) A1 Le, Vien A1 Nhu, Nguyen Thi Khanh A1 Cerdeno-Tarraga, Ana A1 Campbell, James I. A1 Tuyen, Ha Thanh A1 Nhu, Tran Do Hoang A1 Tam, Pham Thi Thanh A1 Schultsz, Constance A1 Thwaites, Guy A1 Thomson, Nicholas R. A1 Baker, StephenYR 2015 T1 Genetic characterization of three qnrS1-harbouring multidrug-resistance plasmids and qnrS1-containing transposons circulating in Ho Chi Minh City, Vietnam JF Journal of Medical Microbiology, VO 64 IS 8 SP 869 OP 878 DO https://doi.org/10.1099/jmm.0.000100 PB Microbiology Society, SN 1473-5644, AB Plasmid-mediated quinolone resistance (PMQR) refers to a family of closely related genes that confer decreased susceptibility to fluoroquinolones. PMQR genes are generally associated with integrons and/or plasmids that carry additional antimicrobial resistance genes active against a range of antimicrobials. In Ho Chi Minh City (HCMC), Vietnam, we have previously shown a high frequency of PMQR genes within commensal Enterobacteriaceae. However, there are limited available sequence data detailing the genetic context in which the PMQR genes reside, and a lack of understanding of how these genes spread across the Enterobacteriaceae. Here, we aimed to determine the genetic background facilitating the spread and maintenance of qnrS1, the dominant PMQR gene circulating in HCMC. We sequenced three qnrS1-carrying plasmids in their entirety to understand the genetic context of these qnrS1-embedded plasmids and also the association of qnrS1-mediated quinolone resistance with other antimicrobial resistance phenotypes. Annotation of the three qnrS1-containing plasmids revealed a qnrS1-containing transposon with a closely related structure. We screened 112 qnrS1-positive commensal Enterobacteriaceae isolated in the community and in a hospital in HCMC to detect the common transposon structure. We found the same transposon structure to be present in 71.4 % (45/63) of qnrS1-positive hospital isolates and in 36.7 % (18/49) of qnrS1-positive isolates from the community. The resulting sequence analysis of the qnrS1 environment suggested that qnrS1 genes are widely distributed and are mobilized on elements with a common genetic background. Our data add additional insight into mechanisms that facilitate resistance to multiple antimicrobials in Gram-negative bacteria in Vietnam., UL https://www.microbiologyresearch.org/content/journal/jmm/10.1099/jmm.0.000100