title: Novel arrangement of the blaCTX-M-55 gene in an Escherichia coli isolate coproducing 16S rRNA methylase.
abstract: A multi-drug resistant Escherichia coli C21 was isolated from a chicken in China. It was shown to be positive for the presence of the blaTEM-1, blaCTX-M-55 and rmtB genes by PCR. This strain was examined by phylogenetic grouping, conjugation experiments, plasmid analysis, PCR-based replicon typing and multi-locus sequence typed (MLST). The genetic environment of blaCTX-M-55 was investigated by PCR mapping. The strain belonged to phylogroup A, ST156. The blaCTX-M-55 and rmtB genes were found to be present in separate plasmids that belonged to the IncI1 and IncN families, respectively. These antibiotic-resistant plasmids could be transferred to the recipient strain alone or together. A new arrangement of ISEcp1Δ-IS1294-ΔISEcp1-blaCTX-M-55 -ORF477, in which the ISEcp1 element was disrupted by another IS1294 element, was identified initially. Conjugative transfer and IS elements found in this study could lead to the rapid dissemination of blaCTX-M-55 and rmtB among strains of Enterobacteriaceae, which could pose a threat to animal husbandry and public health.
authors: College of Animal Science and Veterinary Medicine, Henan Agricultural University, Zhengzhou, China.
authors: Yu-Shan
authors: YS
authors: Pan
authors: Jian-Hua
authors: JH
authors: Liu
authors: Han
authors: H
authors: Hu
authors: Jin-Feng
authors: JF
authors: Zhao
authors: Li
authors: L
authors: Yuan
authors: Hua
authors: H
authors: Wu
authors: Ling-Fei
authors: LF
authors: Wang
authors: Gong-Zheng
authors: GZ
authors: Hu
mesh_terms: D000818:Animals; D002645:Chickens; D002681:China; D002874:Chromosome Mapping; D004251:DNA Transposable Elements; D004269:DNA, Bacterial / Q000235:genetics; D024901:Drug Resistance, Multiple, Bacterial; D004926:Escherichia coli / Q000187:drug effects / Q000201:enzymology / Q000235:genetics* / Q000302:isolation & purification; D023061:Gene Order; D008780:Methyltransferases / Q000235:genetics* / Q000378:metabolism; D058889:Molecular Typing; D016133:Polymerase Chain Reaction; D001618:beta-Lactamases / Q000235:genetics* / Q000378:metabolism
chemical_list: D004251:DNA Transposable Elements; D004269:DNA, Bacterial; D008780:Methyltransferases; C035181:rRNA (adenosine-O-2'-)methyltransferase; D001618:beta-Lactamases
keywords: Escherichia coli; ISEcp1 element; Multidrug resistance; blaCTX-M-55; rmtB