Molecular Characterization of Extended-Spectrum β-Lactamase-Producing Multidrug Resistant Escherichia coli From Swine in Northwest China

Abstract

Objectives: The aim of the present study was to explore the prevalence and molecular characterization of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli collected from pig farms in Northwest China.Methods: Between May 2015 and June 2017, a total of 456 E. coli isolates were collected from fecal samples of healthy and diarrheal pigs in Northwest China to screen the ESBL producers. The β-lactamases, plasmid-mediated quinolone resistance (PMQR) genes and virulence genes among ESBL producers were corroborated by PCR and sequencing. Finally, ESBL producers were further grouped according to phylogenetic background and genetic relatedness.Results: Forty-four (9.6%) out of the 456 E. coli isolates were identified as ESBL-producing isolates. All ESBL producers exhibited multidrug resistance (MDR) phenotype, and more than 90% of the ESBL producers were resistant to amoxicillin, amoxicillin-clavulanic acid, oxytetracycline, enrofloxacin and sulfamethoxazole/trimethoprim. All ESBL producers harbored at least one type of β-lactamase, with blaCTX−M, blaTEM, blaSHV, blaOXA−48, and blaKPC−2 being detected in forty, thirty, seven, four, two and one isolates, respectively. Sequencing revealed the most common blaCTX−M subtype was blaCTX−M−14 (n = 24), followed by blaCTX−M−15 (n = 14), blaCTX−M−64 (n = 11), blaCTX−M−9 (n = 10) and blaCTX−M−123 (n = 9). qnrS (n = 23) was the predominant PMQR gene, and all PMQR genes were detected in co-existence with β-lactamase genes. estA (n = 18) and F4 (n = 18) were the most prevalent enterotoxin and fimbrial adhesin, respectively, and 27 different virotypes were found with respect to the association of enterotoxins and fimbrial adhesins. Twenty-four different sequence types (STs) were identified among 44 ESBL producers, and clones ST405, ST10 and ST648 were strongly present in more than one-third (34.1%) of ESBL producers.Conclusion: All ESBL-producing E. coli isolates exhibited MDR phenotype, and showed high prevalence of β-lactamase and PMQR genes. Especially, one isolate harbored ESBL genes blaTEM, blaSHV, blaCTX−M−9, blaCTX−M−14, blaCTX−M−64, and carbapenemase gene blaOXA−48 and blaKPC−2, as well as PMQR genes qnrS, qnrB, qnrD, qepA and aac(6')-Ib-cr.

Prevalence and characteristics of extended-spectrum β-lactamases-producing Escherichia coli from broiler chickens at different day-age

“…All ESBL producers demonstrated multidrug resistance profiles. It is higher than that found in previous similar studies in pigs (9.6%) and surface waters (2.8%) in Shaanxi Province ( Liu, et al., 2018 ), whereas remarkably lower than that in dogs (24.2%) and retail foods (22.3%) in Shaanxi Province ( Xi et al., 2015 , Liu et al., 2016 ). In addition, among the E. coli analyzed in this study, the prevalence of ESBL producers (13.2%) is considerably lower than that previously found in chickens in Henan Province (60.8%) during 2007 to 2008 ( Yuan, et al., 2009 ) and Northeast China (Heilongjiang, Jilin and Liaoning Province, 100%) during 2011 to 2013 ( Tong, et al., 2015 ).…”

Genetic and Virulence Characteristics of a Hybrid Atypical Enteropathogenic and Uropathogenic Escherichia coli (aEPEC/UPEC) Strain

“…E. coli strains of the ST10 have been frequently associated with UTI in several countries, including Brazil (Gonçalves et al, 2016 ; Hertz et al, 2016 ; Campos et al, 2018 ). Other studies have also reported the isolation of E. coli strains of the ST10 from the environment and food, as well as from bloodstream infections and diarrhea, evidencing the versatility of colonization of this ST (Arais et al, 2018 ; Liu et al, 2018 ; Mohsin et al, 2018 ; Yamaji et al, 2018 ).…”

<p>Characterization of Hypervirulent Extended-Spectrum β-Lactamase-Producing <em>Klebsiella pneumoniae</em> Among Urinary Tract Infections: The First Report from Iran</p>

“…Additionally, plasmid-mediated quinolone resistance (PMQR) genes are associated with ESBL production, and the spread of co-expressing PMQRs and ESBL isolates contributes to the growing concerns regarding MDR isolates. 21 Also, hvKp strains are of major importance as they are hypervirulent and highly transmissible. 18 …”