Characterization of Tn6238with a New Allele ofaac(6′)-Ib-cr

Abstract

ABSTRACTHere, we report that the genetic structure of Tn1331remained conserved in Argentina from 1989 to 2013 (72 of 73 isolates), with the exception being the plasmid-borne Tn1331-like transposon Tn6238containing a newaac(6′)-Ib-crallele recovered from a colistin-resistantKlebsiella pneumoniaeclinical isolate. A bioinformatic analysis ofaac(6′)-Ib-like gene cassettes suggests that this newaac(6′)-Ib-crallele emerged through mutation or homologous recombination in the Tn1331genetic platform. Tn6238is a novel platform for the dissemination of aminoglycoside and fluoroquinolone resistance determinants.