New complex class 1 integron carrying an ISCR1 element in Escherichia coli clinical isolates harbouring the b/a(CMY-11) gene

1 Myongji University
Journal of Medical Microbiology (Impact Factor: 2.27). 10/2009; 59(Pt 1):132-4. DOI: 10.1099/jmm.0.012559-0
Source: PubMed

ABSTRACT Plasmid profiles, Southern blot hybridization, and conjugation assays revealed that the blaCMY-11 gene, responsible for beta-lactam resistance, was located on a noble complex class 1 integron within a conjugative plasmid. A sul1-type class 1 integron, harboring dfrA12, orfF, and aadA2a gene cassettes, was identified upstream of an ISCR1 element and ended with a truncated 3' conserved segment. The nucleotide sequence analyses of blaCMY-1, blaCMY-8, blaCMY-9, and blaCMY-11 genes indicate that there might be past transposition events by the ISCR1 element upstream of blaCMY-11. For the first time, a unique gene (yqgF-yqgE-gshB-orf97-orf105) array was detected between blaCMY-11 and a duplicate of the 3' conserved segment.

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