牛羊肉中肠出血性大肠杆菌O_(157):H_7的检测

目的]为青海省部分地区市售的羊肉、牛肉进行了大肠杆菌O157:H7的检测。方法]样品先用mEC肉汤增菌,然后在选择性培养基TC-SMAC培养,再根据GenBank上已发表的大肠杆菌O157:H7rfbE、fliC和eacA抗原基因的保守序列设计3对引物,进行多重PCR鉴定,将可疑菌接种于MUG-LST,进行微量生化试验鉴定。结果]在各1株牛、羊肉分离菌中多重PCR同时扩增出了大小为678、560和368 bp的3条特异性条带,分离菌的生化反应特性符合大肠杆菌的特征。结论]在羊、牛肉各1份样品中检出了E.coli O157:H7。

Detection of Escherchia coli O157:H7 from Beef and Mutton

Objective] To detect the Escherchia coli O157∶H7 from beef and mutton in Qinghai.Method] The collected samples were cultured in mEC+ n broth,at 41 ℃ for 24 hours,the enriched cultures were cultivated on TC-SMAC plates at 37 ℃ for another 24 hours and 3 pairs of primers were designed based on the rfbE,fliC and eacA genes of E.coli O157∶H7 in GenBank and multiplex PCR were established specific to rfbE,fliC and eacA gene.The suspicious bacterial were cultivated on MUG-LST and preliminarily identified by micro-biochemical reactions.Result] Fragments of 678 bp(rfbE),560 bp(fliC) and 368 bp(eacA) could be amplified from beef and mutton isolated bacteria respectively and its micro-biochemical reactions characteristics was the same with E.coli O157∶H7.Conclusion] E.coli O157∶H7 was detected from beef and mutton samples respectively.