title: Prevalence and characterization of hybrid blaCTX-M among Escherichia coli isolates from livestock and other animals.
abstract: This study investigated 248 extended-spectrum β-lactamase-producing Escherichia coli isolates from 2012 to 2013 for hybrid blaCTX-M genes. blaCTX-M genes were detected in 228 isolates of which 14 isolates were hybrid blaCTX-M positive (6 blaCTX-M-123, 6 blaCTX-M-64, and 2 blaCTX-M-132). The 14 hybrid blaCTX-M-carrying isolates (8 from chickens, 2 each from pigs and cattle, 1 each from dog and rodent) were genetically diverse. All but 2 hybrid blaCTX-M were carried on IncI1 (5 blaCTX-M-123) and IncI2 (6 blaCTX-M-64 and one blaCTX-M-132) plasmids. Our IncI1 and IncI2 plasmids had pHNAH4-1-like and pHN1122-1-like restriction fragment length polymorphism patterns, respectively. Genetic relatedness of the plasmids to pHNAH4-1 and pHN1122-1 were confirmed by complete sequencing of 3 plasmids, pCTXM123_C0996, pCTXM64_C0967, and pCTXM132_P0421. Plasmids closely related to pHNAH4-1 and pHN1122-1 and carrying different blaCTX-M alleles have been reported from multiple geographic areas in China previously. The findings highlighted the wide dissemination of hybrid blaCTX-M variants in different parts of China.
authors: Carol Yu Centre for Infection and Department of Microbiology, Queen Mary Hospital, University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China. Electronic address: plho@hkucc.hku.hk.
authors: Pak-Leung
authors: PL
authors: Ho
authors: Carol Yu Centre for Infection and Department of Microbiology, Queen Mary Hospital, University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China.
authors: Melissa Chun-Jiao
authors: MC
authors: Liu
authors: Carol Yu Centre for Infection and Department of Microbiology, Queen Mary Hospital, University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China.
authors: Wai-U
authors: WU
authors: Lo
authors: Carol Yu Centre for Infection and Department of Microbiology, Queen Mary Hospital, University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China.
authors: Eileen Ling-Yi
authors: EL
authors: Lai
authors: Department of Biomedical Sciences, College of Science and Engineering, City University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China.
authors: Terrence Chi-Kong
authors: TC
authors: Lau
authors: Department of Biomedical Sciences, College of Science and Engineering, City University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China.
authors: Oi-Kwan
authors: OK
authors: Law
authors: Carol Yu Centre for Infection and Department of Microbiology, Queen Mary Hospital, University of Hong Kong, Hong Kong Special Administrative Region, People's Republic of China.
authors: Kin-Hung
authors: KH
authors: Chow
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000818:Animals; D000829:Animals, Domestic / Q000382:microbiology*; D002681:China / Q000453:epidemiology; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics* / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000382:microbiology / Q000662:veterinary*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010957:Plasmids / Q000032:analysis / Q000145:classification; D015995:Prevalence; D011995:Recombination, Genetic; D015183:Restriction Mapping; D012377:Rodentia / Q000382:microbiology*; D017422:Sequence Analysis, DNA; D014552:Urinary Tract Infections / Q000453:epidemiology / Q000382:microbiology*; D055815:Young Adult; D001618:beta-Lactamases / Q000235:genetics*
chemical_list: D001618:beta-Lactamases
keywords: Antimicrobial resistance; Cefotaxime resistance; Enterobacteriaceae; Extended-spectrum β-lactamases; Molecular epidemiology; Plasmids