摘要
根据产vero毒素大肠杆菌(VTEC)产生的vero毒素1(VT1)和vero毒素2(VT2)的基因序列,合成了2对寡核苷酸引物,建立了聚合酶链式反应(PCR)扩增方法。共对4株产vero毒素大肠杆菌和其他7个属的41株肠道致病菌中的VT基因进行了检测,结果仅从用传统组织培养方法确定为VT阳性的产vero毒素大肠杆菌和痢疾1型志贺氏菌提取的DNA中观察到了PCR扩增产物,而从其他肠道致病菌提取的模板DNA中未扩增出任何DNA片段。用这2对引物可以清楚地区分产VT1、VT2或VT1/VT2的大肠杆菌。PCR扩增方法的检测敏感性为320pg全细菌DNA,用vt1引物可以检测出低达32pg的全细菌DNA。
Two sets of synthetic oligonucleotide primers derived from sequences of the verotoxin 1 (VT1) and verotoxin 2 (VT2) genes were used in a polymerase chain reaction (PCR) amplification procedure to detect these genes in some enteric pathogens. A total of 4 verotoxin producing Escherichia coli strains and 41 other recognized pathogens were studied. PCR amplification products identifying the VT1 and VT2 gene sequences were observed only in DNA extracted from strains found to be VT positive by traditional tissue culture assays. The primers were able to distinguish clearly the VT1 and/or VT2 producing strains of Escherichia coli. Template DNA extracted from other enteric pathogens was found to be negative with the excepion of 1 strain of Shigella dysenteriae type 1 in which a good amplification with the VT1 primer was observed. The sensitivity of the PCR procedure for detection of both VT1 and VT2 genes was determined to be 320 pg of total cell DNA. Furthermore, the VT1 gene was easily detected when only 32 pg of DNA was used as a template in the PCR procedure.
出处
《中国兽医学报》
CAS
CSCD
北大核心
1998年第4期342-345,共4页
Chinese Journal of Veterinary Science
基金
国家自然科学基金