山东省食品中单核细胞增生李斯特菌脉冲场凝胶电泳分型

Molecular typing of Listeria monocytogenes isolated from foods in Shandong Province by pulsed-field Gel electrophoresis

目的了解山东省2007～2009年不同食品来源的单核细胞增生李斯特茵（LM）各菌株之间的遗传相关性和流行病学意义，建立分子分型数据库。方法采用PulseNet标准方法对分离到的100株单核细胞增生李斯特菌进行脉冲场凝胶电泳（PFGE），不同菌株产生的电泳图谱经BioNumerics软件进行比对，分析菌株问的相关性。结果单核细胞增生李斯特菌DNA用AscI酶切后，经PFGE得到10—15个条带，可将100株茵分为31个PFGE型别，其中以4型为主。结论山东省食品中的LM来源于不同的克隆株，但部分LM有不同程度的相关性；PFGE是分析LM同源性的有效方法，对LM的流行趋势、分布特点和分子流行病学研究具有重要的意义。

Objective To investigate the genetic correlation and epidemiological significance of different genotypes of Listeria monocytogenes （LM） isolated from foods in Shandong Province during 2007-2009. Methods 100 strains were genotyped by pulsed-field gel electrophoresis （ PFGE）, and the images were processed by cluster analysis using computer BioNumerics software. Results Digestion of DNA with Asc I yielded 10 to 15 bands. The 100 Shandong Listeria monocytogenes were sub-typed into 31 PFGE types, of which type 4 was the majority. Conclusions In Shandong Province, LM strains were from different clones, but a number of LM strains were closely related. PFGE is a useful method in analyzing homology of LM, and it is of great significance in molecular epidemiological studies of LM.