分子信标探针技术检测沙门菌invA基因

目的 研究沙门菌的分子信标基因检测方法。方法 在PCR反应体系中加入分子信标探针,探针的5’端标记6-fluorescine(6-FAM),3’端标记4-(dimethylaminophenylazo)benzoic acid (DABCYL),对沙门菌invA基因PCR产物进行荧光检测。结果 肠炎沙门菌、甲型副伤寒沙门菌、乙型副伤寒沙门菌、伤寒沙门菌“H”、伤寒沙门菌和肠侵袭型大肠杆菌的荧光值分别为161.6、104.5、85.9、83.1、94.8、46.1,Ax值(样本荧光值-空白对照荧光值)分别为121.3、64.2、45.6、42.8、54.5、5.8,沙门菌的Ax值均大于21,结果阳性,与琼脂糖电泳分析结果一致。结论 分子信标探针技术可以准确、快速、简便进行沙门菌invA基因检测。

Detection of the Salmonella invasion gene invA using molecular beacon probe

Objective To detect Salmonella invasion gene invA. Methods The invA gene of Salmonella was amplified with PCR reaction system containing the molecular beacon probe labeled with 6-carboxy fluorescein (6-FAM) at its 5' end and with (4-dimethylaminophenylazo)benzoic acid (DABCYL) at its 3' end, and the fluorescence signal was read at the end of PCR. Results The fluorescence values of S.enteritidis, S. paratyphi A, S. paratyphi B, S.typhi antigen H, S.typhi, and enteroinvasive E.coli were 161.6, 104.5, 85.9, 83.1, 94.8 and 46.1 respectively. The results of PCR of Salmonella was consistent with that of agarose gel electrophoresis. Conclusion PCR with fluorogenic molecular beacon probe is rapid, specific, sensitive, and convenient for detecting Salmonella with invA gene.