罗非鱼水产品中的喹诺酮类药物耐药菌和耐药基因检测分析  

Detection and analysis of quinolone resistance and resistance-associated genes in bacteria isolated from tilapias sold in the supermarkets

作　　者：郭学中 张瑞泉[1] 姜兰[1] 谭爱萍[1] 邓玉婷 李金祥 赵飞[1] 刘付翠 何山 GUO Xuezhong;ZHANG Ruiquan;JIANG Lan;TAN Aiping;DENG Yuting;LI Jinxiang;ZHAO Fei;LIUFU Cui;HE Shan(Key Laboratory of Fishery Drug Development,Ministry of Agriculture and Rural Affairs;Key Laboratory of Aquatic Animal Immune Technology of Guangdong Province;Pearl River Fisheries Research Institute,Chinese Academy of Fishery Sciences,Guangzhou 510380,China;College of Fishery and Life Science,Shanghai Ocean University,Shanghai 201306,China;Key Laboratory of Aquatic Disease&Waterfowl Breeding of Guangzhou,Zhongkai University of Agriculture and Engineering,Guangzhou 510225,China)

机构地区：[1]中国水产科学研究院珠江水产研究所,农业农村部渔用药物创制重点实验室,广东省水产动物免疫技术重点实验室,广东广州510380 [2]上海海洋大学水产与生命学院,上海201306 [3]仲恺农业工程学院广州市水产病害与水禽养殖重点实验室,广东广州510225

出　　处：《中国水产科学》2018年第5期1032-1039,共8页Journal of Fishery Sciences of China

基　　金：广东省自然科学基金项目(2015A030313701);现代农业产业技术体系专项资金项目(CARS-46)

摘　　要：本研究旨在了解水产品中携带的细菌对喹诺酮类药物的耐药状况及耐药基因类型,评估水产品中细菌耐药性风险。从广州市14家超市随机购买100条鲜活的罗非鱼,高通量测序分析结果显示,罗非鱼携带的优势菌群为大肠埃希菌(Escherichia hydrophila)和气单胞菌(Aeromonas)。采用大肠埃希菌和气单胞菌筛选培养方法,分别从鳃、肌肉和肠内容物筛选分离出182株大肠埃希菌和280株气单胞菌;运用琼脂二倍稀释法测定了恩诺沙星和环丙沙星对分离菌株的最小抑菌浓度;通过PCR法扩增质粒介导的喹诺酮类耐药(PMQR)基因(qnrA、qnr B、qnrC、qnrD、qnrS、aac(6￠)-Ib-cr、qepA、oqxAB)并进行测序和比对分析。结果显示,分离的气单胞菌对恩诺沙星和环丙沙星的耐药率分别为2.50%和2.14%;分离的大肠埃希菌对恩诺沙星和环丙沙星的耐药率分别为25.82%和18.13%。肌肉中分离的气单胞菌和大肠埃希菌对恩诺沙星和/或环丙沙星的耐药率均低于鳃和肠道的;各组织分离的大肠埃希菌对氟喹诺酮类药物的耐药率均远高于气单胞菌。分离菌株中,携带PMQR基因的大肠埃希菌占59.89%,且检出的耐药基因种类较多,包括qnrB、qnrD、qnrS、aac(6?)-Ib-cr和oqx AB;而携带PMQR基因的气单胞菌仅占6.79%,只检出耐药基因aac(6￠)-Ib-cr和qnrS。结论认为,罗非鱼食用部分肌肉携带的耐药菌较少,食品相对安全;肠道和鳃组织携带的耐药菌以大肠埃希菌为主,而且大部分菌株携带有不同类型的PMQR基因,存在一定的耐药传播隐患。The aim of this study was to investigate and analyze quinolone resistance and plasmid-mediated quinolone resistance(PMQR)genes in Aeromonas and Escherichia coli isolated from the commercial aquatic products sold in Guangzhou’s supermarkets,and to assess the quality and safety of these aquatic products.One hundred live tilapias were collected from 14 supermarkets in Guangzhou.The results of high-throughput sequencing analysis indicated that Escherichia coli and Aeromonas were the dominant bacteria.According to bacterial screening culture methods,280 Aeromonas and 182 E.coli strains were isolated from the gills,muscles,and intestinal contents,respectively.All the isolates were evaluated for resistance to enrofloxacin(ENR)and ciprofloxacin(CIP)by agar dilution method.All of the 280 Aeromonas and 182 E.coli strains were also screened for the qnr,qepA,aac(6?)-Ib-cr,and oqxAB genes using PCR.The results showed that 7(2.50%)Aeromonas and 47(25.82%)E.coli isolates were resistant to ENR,while 6(2.14%)Aeromonas and 33(18.13%)E.coli isolates were resistant to CIP.The resistance rates of ENR and/or CIP in Aeromonas and E.coli isolates obtained from the muscles were much lower than those in the microorganisms isolated from the gills and intestinal contents.All the E.coli isolates obtained from different issues were much more resistant to fluoroquinolones than the Aeromonas isolates.Of these 182 E.coli isolates,59.89%isolates harbored PMQR genes,and 5 types of PMQR genes were detected,including qnrB,qnrD,qnrS,aac(6?)-Ib-cr,and oqxAB.Of the 280 Aeromonas isolates,6.79%harbored PMQR genes,and only aac(6?)-Ib-cr and qnrS were detected.Only a few resistant bacteria were screened in the muscles,which form the edible part of the tilapia;so,the food products were considered relatively safe.However,resistant E.coli was predominantly isolated from the intestinal contents and gills,and most of the E.coli isolates carried various types of PMQR genes,suggesting a potential risk of drug-resistant E.coli transmission from these tissues.Th

关 键 词：水产品 气单胞菌 大肠埃希菌 喹诺酮类耐药 PMQR 

分 类 号：S948[农业科学—水产养殖]