非O1非O139群霍乱弧菌多重PCR和SYBR Green实时PCR检测方法的建立

摘要

目的 建立检测非O1非O139群霍乱弧菌的多重PCR和SYBR Grcen实时PCR方法.方法 分别以霍乱弧菌的外膜蛋白基因(ompW)、O1和O139群O抗原编码基因(rfb)设计引物,建立多重PCR和SYBR Green实时PCR方法,评价两种方法检测非O1非O139群霍乱弧菌的特异性、重复性和一致性及最低检测菌量.结果 建立了检测非O1非O139群霍乱弧菌的多重PCR和SYBR Green实时PCR方法,根据特异性条带(多重PCR)和特异性熔解温度(SYBR Green实时PCR),两种方法均能特异性检测非O1非O139群霍乱弧菌,并能鉴别其他弧菌(5种)和肠道杆菌(3种);两种方法的最低检测菌量分别为7×104 c fu/ml(多重PCR)和7×102 cfu/ml (SYBRGreen实时PCR),差异有统计学意义(P＜0.05);对实时PCR的重复性检测,批内变异系数(CV)为0.22％ ～ 0.92％,批间CV为0.27％～1.41％;经370株非O1非O139群霍乱弧菌的检测,两种方法的一致性均为100％.结论 建立的两种方法其特异性、敏感性及重复性均好,可适用于不同条件下非O1非O139群霍乱弧菌的检测和鉴定.%Objective To develop methodology of both multiple PCR and real-time SYBR green PCR for the detection of Vibrio cholerae (V.cholerae) serogroups non-O1 and non-O139.Methods The outer membrane protein gene (ompW) specific for V.cholerae,as well as O antigen rfb genes specific for both O1 and O139,were used for the design of the PCR primers.Both multiple PCR and real-time SYBR green PCR systems were used to detect both O1 and O139.Specific rfb genes and ompW were developed to evaluate their specificity,limit of detection,reproducibility and consistency.Results We established multiple PCR and real-time SYBR green PCR methods.According to the specific electrophoretic bands (multiple PCR) and the specific melt curve temperature (real-time SYBR green PCR),both methods could specifically detect the non-O1,non-O139 V.cholerae,and to differentiate them from O1,O139 V.cholerae,other five Vibrios and 3 intestinal bacteria.The detection limits were 7 × 104 cfu/ml (multiple PCR) and 7 × 102 cfu/ml (real-time SYBR green PCR),with statistically significant difference seen (P＜0.05).For the reproducibility of real-time SYBR green PCR,the external coefficient variation ranging from 0.22％ to 0.92％ while the internal coefficient variation ranging from 0.27％ to 1.41％.370 strains of non-O1,non-O139 V.cholerae,were detected,with both consistency rates as 100％.Conclusion Both multiple PCR and real-time SYBR green PCR could detect non-O1,non-O139 V.cholerae,rapidly,specifically,and reproducibly,that could all be used for the detection and identification of non-O 1,non-O 139 under different conditions.