F33:A−:B− and F2:A−:B− Plasmids Mediate Dissemination of rmtB-bla CTX-M-9 Group Genes and rmtB-qepA in Enterobacteriaceae Isolates from Pets in China

Abstract

This study investigated the prevalence of 16S rRNA methylase genes in 267 Enterobacteriaceae isolates collected from pets. The rmtB gene was detected in 69 isolates, most of which were clonally unrelated. The coexistence of the rmtB gene with the bla _CTX-M-9 group genes and/or qepA within the same IncFII replicons was commonly detected. The two dominant types of IncF plasmids, F2:A−:B−, carrying rmtB-qepA , and F33:A−:B−, carrying the rmtB-bla _CTX-M-9 group genes (and especially bla _CTX-M-65 ), shared restriction patterns within each incompatibility group.