杭州地区单核细胞增生李斯特菌食品分离株分子型别研究

Molecular characteristics of Listeria monocytogenes foodborne isolates in Hangzhou,China

目的研究杭州地区单核细胞增生李斯特菌(Listeria monocytogenes)食品分离株的分子分型情况,了解当地流行株的型别特征。方法用脉冲场凝胶电泳(PFGE)和多位点序列分型(MLST)的方法对单核细胞增生李斯特菌进行分子分型。PFGE结果进行聚类分析,并绘制MLST数据的最小生成树。结果 6个血清型组成的133株杭州食品分离株共获得19个MLST型别,并发现1个新的ST型ST767。ST9和ST121是数量最多的型别。用AscI和ApaI酶切分别获得33和45个PFGE带型。结论杭州地区单核细胞增生李斯特菌食品分离株分子型别分布广泛,大部分菌株是可引起人李斯特菌病的Lineage I和Lineage II菌株。食品中单核细胞增生李斯特菌的污染比较严重,应加强监测与管理以防食源性疾病的发生。

We determined molecular characteristics of Listeria monocytogenes foodborne isolates in Hangzhou and investigated the characterization of local strains. Multi-locus sequence typing（MLST） and pulsed-field gel eleetrophoresis（PFGE） were applied to identify molecular types of Listeria monocytogenes isolates. Results showed that a total of 133 strains of 6 serotypes were divided into 19 MLST types including a new type ST767. ST9 and ST121 were the major ST types. There were 33 and 45 PFGE patterns characterized by AscI and ApaI. The molecular types of Listeria monocytogenes strains were widely distributed in Hangzhou. It is indicated that the major clusters were Lineage I and Lineage II which will cause listeriosis. The contamination of Listeria monocytogenes in food is serious in Hangzhou and the surveillance and management should he strengthened to prevent the food borne diseases.