Characterization of a cfr-bearing integrative and conjugative element in Proteus cibarius coharbouring tet(X6) on the chromosome.

The I tet i (X6) gene, I cfr i gene and ICEs are likely to have undergone genetic recombination during transmission, resulting in the formation of CZP50. In this study, we identified a strain CZP50 encoding the I tet i (X6) gene on the chromosome and the I cfr i gene on the ICE I Pci i ChnCZP50. Plasmid- and chromosome-mediated multiresistance gene I cfr i and tigecycline resistance gene I tet i (X6) have been reported in I Proteus i spp. isolated from food-producing animals.[1] Recently, two chromosome-mediated I tet i (X6) genes in I Proteus cibarius i were found in chicken faeces.[2] In addition, integrative and conjugative elements (ICEs) carrying the I cfr i were identified in I Proteus mirabilis i isolated from swine-derived faeces and cloacae and could be transferred into I Escherichia coli i by conjugation, providing for the dissemination of antibiotic resistance genes (ARGs).[3],[4] Despite the high mobility of the I tet i (X6) and I cfr i genes, coexistence of two such genes on one chromosome has not been reported. [Extracted from the article]