聚合酶链反应扩增大肠杆菌志贺样毒素基因

Amplification and Detection of Shiga-like Toxin Genes in Shiga-like Toxin producing Esherichia coli by PCR

两对寡核苷酸引物通过聚合酶链反应扩增大肠杆菌志贺样毒素Ｉ（ＳＬＴ Ｉ）和志贺样毒素Ⅱ（ＳＬＴⅡ）基因，在单一反应中，两对引物分别扩增出１３０ｂｐ（ＳＬＴⅠ）和３４６ｂｐ（ＳＬＴ Ⅱ）的ＤＮＡ 片段，扩增片段经地高辛标记寡核苷酸探针Ｓｏｕｔｈｅｒｎ 印迹杂交分析，证实为ＳＬＴ Ⅰ和ＳＬＴ Ⅱ基因产物。同一扩增反应中应用ＳＬＴⅠ和ＳＬＴⅡ复合引物进行扩增，不同基因型志贺样毒素大肠杆菌从样品中鉴定出。８６９份牛、猪腹泻粪样ＤＮＡ 样品通过ＰＣＲ进行了测定，其中，３％ 检出志贺样毒素大肠杆菌，与牛出血性腹泻、猪水肿病有关。

Two differdnt sets of oligonucleotide primers synthesized were used to amplify the Shiga like toxin(SLT)genes in Shiga like toxin producing Esherichia coli (SLTEC) by PCR.130bp (SLT Ⅰ) and 346bp (SLT Ⅱ) segments were obtained with SLT Ⅰ and SLT Ⅱ primers in DNA extracted directly fron SLTEC strains and stool samples by the reaction.Southern blot analysis showed the PCR fragments were the SLT gene products.Two types of SLTEC strains corresponding to SLT Ⅰ and SLT Ⅱ genotypes were distinguished by PCR with multiple prinmers in samples.