华南四省食品中空肠弯曲菌分离株的毒力相关基因分析和ERIC-PCR分型

Virulence-associated gene detection and ERIC-PCR typing of Campylobacter jejuni strains isolated from foods in four Southern Chinese provinces

摘要:

摘要:【目的】了解空肠弯曲菌(Campylobacter jejuni)在华南四省食品中的污染状况及其遗传多样性，为食源性病原菌的风险监测和控制提供基础数据。【方法】采用传统国标和MPN组合的方法对华南四省市售生鲜禽畜肉及其制品、生食蔬菜、熟食、水产品、速冻食品、奶制品、食用菌7 大类食品进行C.jejuni污染调查，对分离到的C. jejuni 菌株进行12种毒力相关基因检测分析和ERIC-PCR分型。【结果】2011－2012年共检测样品558份，检出阳性样品14份，检出率2.51%，其中肉与肉制品的检出率达13.2%，污染量达8.77 MPN/g，获得C. jejuni14株。毒力相关基因分析显示9种毒力相关基因的携带率超过50%，而pldA 和wlaN的携带率均为14.3%，virB11的携带率为0。ERIC-PCR分析结果显示15株C. jejuni可分为3簇共10种基因型，其中簇A中有4株的指纹图谱基本相同。【结论】华南四省中的生鲜禽肉类样品，存在不同程度的空肠弯曲菌污染，尤其是福州的鸭肉样品，其MPN值大于110 MPN/g，应加强生禽肉类的食品安全防控。

关键词:关键词:空肠弯曲菌，ERIC-PCR分型，毒力相关基因

Abstract:

Abstract:［Objective］To know food contamination and genetic diversity of Campylobacter jejuni in four provinces of South China，and to provide data for C. jejuni-associated foodborne disease prevention and control.［Methods］According to the national standard and the most probable number(MPN) method，we detected the contamination of C. jejuni from 558 food samples including vegetables，meat product，cooked food，seafood，frozen food，dairy product and edible fungi during 2011 and 2012．The isolates were used to detect 12 virulence-associated genes with PCR methods and construct ERICPCR fingerprints.［Results］Fourteen positive samples were determined from 558 samples，and all positive samples come from meat product samples．The average value of MPN of positive samples was 8.77 MPN/g．Virulence-associated gene analysis reveals that more than 50% of the C.jejuni isolates had at least 9 virulence genes．Interestingly，virB11 gene was not found and the genes of pldA and wlaN were 14.30% in all isolates．Total of 15 C．jejuni isolates could be divided into 10 genotypes belonging to 3 clusters by ERIC-PCR fingerprints.［Conclusion］Meat product was the main source of C. jejuni food contamination in four provinces of South China．More control measures must be taken to avoid C．jejuni contamination.

Key words:Keywords: Campylobacter jejuni，ERIC-PCR typing，virulence-associated genes