title: Mechanisms of resistance to cephalosporin and emergence of O25b-ST131 clone harboring CTX-M-27 β-lactamase in extraintestinal pathogenic Escherichia coli from dogs and cats in Japan.
abstract: Thirty-three cefazolin-resistant extraintestinal pathogenic Escherichia coli strains from companion animals were screened for bla(CMY-1) , bla(CMY-2) , bla(SHV) , bla(TEM) , and bla(CTX-M)  genes. Extended-spectrum β-lactamase-producing strains were further characterized by O serotyping and multilocus sequence typing. It was found that 20 and 17 isolates harbored TEM-1 and CMY-2 β-lactamases, respectively, and 13 isolates harbored both β-lactamases. One isolate harbored DHA-1 β-lactamase. Eleven isolates were found to possess CTX-M β-lactamases (CTX-M-27 [n= 6], CTX-M-14 [n= 3], CTX-M-15 [n= 1], and CTX-M-55 [n= 1]). Of 11 CTX-M-positive strains, four strains were O25b-ST131 clones harboring CTX-M-27, and the remaining seven strains belonged to O6-ST127, ONT-ST354, O159-ST539, O1-ST648, O8-ST1642, O25b-ST2042, and ONT-ST2178.
authors.affiliation: Laboratory of Veterinary Microbiology, Nippon Veterinary and Life Science University, Musashino, Tokyo, Japan. k-harada@muses.tottori-u.ac.jp
authors.forename: Kazuki
authors.initials: K
authors.lastname: Harada
authors.forename: Yuka
authors.initials: Y
authors.lastname: Nakai
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Kataoka
mesh_terms: D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D002371:Cat Diseases / Q000382:microbiology*; D002415:Cats; D002511:Cephalosporins / Q000494:pharmacology*; D004283:Dog Diseases / Q000382:microbiology*; D004285:Dogs; D024881:Drug Resistance, Bacterial; D004926:Escherichia coli / Q000145:classification / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*; D004927:Escherichia coli Infections / Q000382:microbiology / Q000662:veterinary*; D029968:Escherichia coli Proteins / Q000235:genetics*; D007564:Japan; D008969:Molecular Sequence Data; D010802:Phylogeny; D001618:beta-Lactamases / Q000235:genetics*
chemical_list: D000900:Anti-Bacterial Agents; D002511:Cephalosporins; D029968:Escherichia coli Proteins; D001618:beta-Lactamases