苏州市食品中单增李斯特菌污染状况及分子特征分析  

Analysis of contamination status and molecular characteristics of Listeria monocytogenes in food in Suzhou City

作　　者：朱莉勤 王波[1] 张宁[1] 邹文燕[1] 王小龙 ZHU Li-Qin;WANG Bo;ZHANG Ning;ZOU Wen-Yan;WANG Xiao-Long(Suzhou Center for Disease Control and Prevention,Suzhou 215004,China)

机构地区：[1]苏州市疾病预防控制中心,苏州215004

出　　处：《食品安全质量检测学报》2022年第3期972-977,共6页Journal of Food Safety and Quality

基　　金：苏州市科技计划项目(SS202043)。

摘　　要：目的研究2016—2020年苏州市各类食品中单增李斯特菌的污染状况及分子特征。方法将采样食品按WS/T464—2015《食物成分数据表达规范》进行分类,计算各类食品污染率,通过聚合酶链式反应(polymerase chain reaction,PCR)和凝胶电泳对毒力基因(inlA、inlB)和耐药相关基因(virR、dltA、dltB、dltC、dltD、mprF)进行检测,通过脉冲场凝胶电泳进行分子分型。结果683件食品中共检出44件阳性样品,总体检出率6.4%。各类食品中以肉类食品的检出率最高(17.2%),肉类食品中以预制肉制品检出率最高(37.2%)。分离的44株单增李斯特菌毒力基因inlA携带率为100.0%,inlB携带率为97.7%,耐药相关基因virR、dltA、dltB、dltC、dltD、mprF的携带率分别为90.9%、100.0%、90.9%、100.0%、95.5%、97.7%。分离株的PFGE型别可分为11个基因型簇,相似度为53.3%~100.0%,有11组100.0%相似度的带型,其中有3组为同一时间,同一地点采集样品所分离菌株。结论苏州市肉类食品特别是预制肉制品单增李斯特菌污染较为严重,而且污染菌株毒力基因和耐药相关基因总体携带率高。PFGE的11种带型中B和E为优势带型,占比40.9%。零售环节存在样品交叉污染单增李斯特菌的风险。Objective To study the contamination status and molecular characteristics of Listeria monocytogenes in various foods in Suzhou City from 2016 to 2020.Methods The food samples were classified according to WS/T 464—2015 Regulation of food composition data expression,and the contamination rates of all kinds of food were calculated.Virulence genes(inlA,inlB)and drug-resistance related genes(virR,dlt A,dltB,dltC,dltD,mpr F)were detected by polymerase chain reaction(PCR)and gel electrophoresis.Molecular typings were performed by pulsed-field gel electrophoresis.Results A total of 44 positive samples were detected out of 683 food samples,with an overall positive rate of 6.4%.Among all kinds of foods,the detection rate of meat was the highest(17.2%),and among the meat foods,the detection rate of pre-made meat products was the highest(37.2%).The isolated 44 Listeria monocytogenes strains of virulence gene inlA carrying rates were 100.0%,and inlB carrying rates were 97.7%.The carrying rates of drug-resistance related genes virR,dlt A,dltB,dltC,dltD and mpr F were 90.9%,100.0%,90.9%,100.0%,95.5%and 97.7%,respectively.The PFGE types of the isolates could be divided into 11 genotype clusters with a similarity of 53.3%~100.0%.There were 11 groups of 100.0%similar band patterns,of which 3 groups were strains isolated from samples collected at the same time and place.Conclusion The contamination of Listeria monocytogenes in meat products,especially pre-made meat products,is serious in Suzhou City,and the overall carrying rates of virulence genes and drug-resistance genes of the strains are high.Among the 11 kinds of PFGE band types,B and E are the dominant band types,accounting for 40.9%.There is a risk of cross-contamination between samples with Listeria monocytogenes in the retail sector.

关 键 词：单增李斯特菌 毒力基因 耐药相关基因 脉冲场凝胶电泳 

分 类 号：R155.5[医药卫生—营养与食品卫生学]