VIM-type metallo-β-lactamase (MBL)-encoding genomic islands in Pseudomonas spp. in Poland: predominance of clc-like integrative and conjugative elements (ICEs).

Objectives To characterize VIM-type metallo-β-lactamase (MBL)-encoding genomic islands (GIs) in Pseudomonas aeruginosa and P. putida group isolates from Polish hospitals from 2001–2015/16. Methods Twelve P. aeruginosa and 20 P. putida group isolates producing VIM-like MBLs were selected from a large collection of these based on epidemiological and typing data. The organisms represented all major epidemic genotypes of these species spread in Poland with chromosomally located bla VIM gene-carrying integrons. The previously determined short-read sequences were complemented by long-read sequencing in this study. The comparative structural analysis of the GIs used a variety of bioinformatic tools. Results Thirty different GIs with bla VIM integrons were identified in the 32 isolates, of which 24 GIs from 26 isolates were integrative and conjugative elements (ICEs) of the clc family. These in turn were dominated by 21 variants of the GI2/ICE 6441 subfamily with a total of 19 VIM integrons, each inserted in the same position within the ICE's Tn 21 -like transposon Tn 4380. The three other ICEs formed a novel ICE 6705 subfamily, lacking Tn 4380 and having different VIM integrons located in another site of the elements. The remaining six non-ICE GIs represented miscellaneous structures. The presence of various integrons in the same ICE sublineage, and of the same integron in different GIs, indicated circulation and recombination of the integron-carrying genetic platforms across Pseudomonas species/genotypes. Conclusions Despite the general diversity of the bla VIM-carrying GIs in Pseudomonas spp. in Poland, a clear predominance of broadly spread and rapidly evolving clc -type ICEs was documented, confirming their significant role in antimicrobial resistance epidemiology. [ABSTRACT FROM AUTHOR]