Cui Mingquan, Zhang Peng, Li Jiyun, Sun Chengtao, Song Li, Zhang Chunping, Zhao Qi, Wu Congming
China Institute of Veterinary Drug Control, Beijing, China.
Beijing Advanced Innovation Center for Food Nutrition and Human Health, College of Veterinary Medicine, China Agricultural University, Beijing, China.
Front Microbiol. 2019 Aug 13;10:1865. doi: 10.3389/fmicb.2019.01865. eCollection 2019.
The objectives of this study were to investigate the prevalence and fluoroquinolone resistant isolated from an integrated broiler chicken supply chain and their molecular characterization. In total, 73 isolates were recovered from a broiler chicken supply chain in Shanghai. isolates were tested for susceptibility to 11 antimicrobial agents using the broth dilution method and were characterized using pulsed-field gel electrophoresis (PFGE). Then, the isolates were examined for mutations in quinolone resistance-determining region (QRDR) of , , , and , and were screened for plasmid-mediated quinolone resistance (PMQR) genes. Lastly, we sequenced the plasmids carrying in six isolates from three sources (two isolated per source). Among 73 isolates, 45 isolates were identified as . Indiana, 24 were . Schwarzengrund, 2 were . Enteritidis, and 2 were . Stanleyville. In addition, high rates of resistance were detected for nalidixic acid (41.1%) and ciprofloxacin (37.0%), while resistance to other test agents was diverse (2.0-100%). . Indiana and . Schwarzengrund isolates from different sources exhibited the same PFGE pattern, suggesting that the isolates possessed high potential to spread along the broiler chicken supply chain. and exhibited frequent missense mutations. Moreover, was the most prevalent PMQR gene in the 73 isolates, and it was found about a new hybrid plasmid. This study concludes a high prevalence of fluoroquinolone resistant in chicken supply chain, threatening the treatment of foodborne diseases. In particular, the emergence of a new hybrid plasmid carrying indicates that the recombination of plasmid carrying resistance gene might be a potential risk factor for the prevention and control strategies of drug resistance.
本研究的目的是调查从一体化肉鸡供应链中分离出的氟喹诺酮耐药性及其分子特征。总共从上海的一个肉鸡供应链中分离出73株菌株。采用肉汤稀释法检测这些菌株对11种抗菌药物的敏感性，并用脉冲场凝胶电泳（PFGE）进行特征分析。然后，检测这些菌株在gyrA、gyrB、parC和parE喹诺酮耐药决定区（QRDR）的突变情况，并筛选质粒介导的喹诺酮耐药（PMQR）基因。最后，对来自三个来源（每个来源分离两株）的6株菌株中携带qnr的质粒进行测序。在73株菌株中，45株被鉴定为肠炎沙门氏菌印第安纳亚种，24株为肠炎沙门氏菌施瓦岑格鲁德亚种，2株为肠炎沙门氏菌肠炎亚种，2株为斯坦利维尔沙门氏菌。此外，检测到对萘啶酸（41.1%）和环丙沙星（37.0%）的耐药率较高，而对其他受试药物的耐药情况各不相同（2.0%-100%）。来自不同来源的肠炎沙门氏菌印第安纳亚种和肠炎沙门氏菌施瓦岑格鲁德亚种菌株表现出相同的PFGE图谱，表明这些沙门氏菌菌株具有沿肉鸡供应链传播的高潜力。gyrA和parC表现出频繁的错义突变。此外，qnrS是73株菌株中最普遍的PMQR基因，并且发现了一种新的杂交质粒。本研究得出结论，鸡供应链中氟喹诺酮耐药沙门氏菌的流行率很高，威胁到沙门氏菌食源性疾病的治疗。特别是，携带qnr的新杂交质粒的出现表明，携带耐药基因的质粒重组可能是耐药性防控策略的一个潜在风险因素。
