title: Molecular characterization of a multidrug-resistant strain of enteroinvasive Escherichia coli O164 isolated in Japan.
abstract: Enteroinvasive Escherichia coli (EIEC) O164 strain RIMD05091045 was isolated from a travelling patient suffering from diarrhoea at the Osaka airport quarantine facility in Japan. The strain showed multidrug resistance against streptomycin, spectinomycin, co-trimoxazole (trimethoprim/sulfamethoxazole) and ampicillin, and reduced susceptibility to ciprofloxacin. Molecular characterization of the multidrug-resistance phenotype revealed the presence of a class 1 integron containing three genes, a dihydrofolate reductase type XII gene, dfrXII, which confers resistance to trimethoprim, an aminoglycoside adenyltransferase gene, aadA2, which confers resistance to streptomycin and spectinomycin, and an ORF of unknown function. Southern blot hybridization and conjugation experiments showed that the class 1 integron was located on a transferable plasmid that was less than 90 kb in size. The resistance of EIEC O164 to ampicillin was found to be due to the presence of TEM-1 beta-lactamase. On the other hand, a single mutation that has not previously been described, P158-to-S, was detected downstream of the quinolone-resistance-determining region of parC of topoisomerase IV and may be responsible for the reduced susceptibility to ciprofloxacin in this strain.
authors.affiliation: Laboratory of Food Microbiology and Hygiene, Graduate School of Biosphere Science, Hiroshima University, Higashi-Hiroshima 739-8528, Japan 2Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan.
authors.forename: Ashraf M
authors.initials: AM
authors.lastname: Ahmed
authors.affiliation: Laboratory of Food Microbiology and Hygiene, Graduate School of Biosphere Science, Hiroshima University, Higashi-Hiroshima 739-8528, Japan 2Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan.
authors.forename: Shin-Ichi
authors.initials: SI
authors.lastname: Miyoshi
authors.affiliation: Laboratory of Food Microbiology and Hygiene, Graduate School of Biosphere Science, Hiroshima University, Higashi-Hiroshima 739-8528, Japan 2Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan.
authors.forename: Sumio
authors.initials: S
authors.lastname: Shinoda
authors.affiliation: Laboratory of Food Microbiology and Hygiene, Graduate School of Biosphere Science, Hiroshima University, Higashi-Hiroshima 739-8528, Japan 2Graduate School of Natural Science and Technology, Okayama University, Okayama 700-8530, Japan.
authors.forename: Tadashi
authors.initials: T
authors.lastname: Shimamoto
mesh_terms: D000668:Ampicillin Resistance / Q000235:genetics; D000890:Anti-Infective Agents / Q000494:pharmacology*; D015139:Blotting, Southern; D027101:DNA Topoisomerase IV / Q000235:genetics; D003967:Diarrhea / Q000382:microbiology*; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics; D004587:Electrophoresis, Agar Gel; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics* / Q000472:pathogenicity; D004927:Escherichia coli Infections / Q000382:microbiology*; D006801:Humans; D032023:Integrons; D007564:Japan; D008826:Microbial Sensitivity Tests; D009713:Nucleotidyltransferases / Q000235:genetics; D016366:Open Reading Frames; D010641:Phenotype; D017354:Point Mutation; D016133:Polymerase Chain Reaction; D013762:Tetrahydrofolate Dehydrogenase / Q000235:genetics; D014195:Travel; D001618:beta-Lactamases / Q000235:genetics
chemical_list: D000890:Anti-Infective Agents; D013762:Tetrahydrofolate Dehydrogenase; D009713:Nucleotidyltransferases; C020565:gentamicin 2''-nucleotidyltransferase; D001618:beta-Lactamases; D027101:DNA Topoisomerase IV