沙门菌tcpS基因的血清型分布及其在特定血清型鉴定中的应用

摘要

A tcpS-based PCR method was established to simultaneously screen Salmonella enterica serovars Enteritidis,Pullorum/Gallinarum,and Dublin.The developed PCR method provides laboratorial support as a convenient and rapid approach for epidemiological investigation,and tcpS can be a potential candidate gene for the development of PCR-based Salmonella identification.The serotype distribution of Salmonella tcpS gene was analyzed by bioinformatic approach.The specificity and sensitivity of the PCR method were determined based on 27 different Salmonella serovars and 10 non-Salmonella strains.The PCR method was applied to clinical Salmonella isolates from one pig farm (48 isolates),one chicken farm (22 isolates) and one cattle farm (11 isolates) from Jiangsu Province.In silico analysis showed that tcpS existed only in Salmonella Enteritidis,Pullorum/Gallinarum,and Dublin.The developed PCR method had potent specificity and sensitivity,and could screen the three specific Salmonella serovars accurately.The coincidence rate of the clinical sample detection was up to 100％.The tcpS-based PCR detection method could screen Salmonella Enteritidis,Pullorum/Gallinarum,and Dublin accurately,and could be an assistant method to the traditional serotyping method.Furthermore,the novel tcpS gene can be a potent gene candidate for the development of PCR method for the identification of Salmonella serovars.%目的 建立基于tcpS基因的PCR鉴定方法,同时筛选肠炎沙门菌、鸡白痢/伤寒沙门菌和都柏林沙门菌,为流行病学调查提供方便快速的实验室技术支持,并为PCR鉴定沙门菌方法的发展提供新的基因候选.方法 利用生物信息学的方法分析沙门菌tcpS基因的血清型分布特点,选择27种不同血清型沙门菌以及10株非沙门菌菌株,对所建立PCR体系的特异性和灵敏性进行检测,并将该方法应用于江苏省分离的48株猪场分离株、22株鸡场分离株和11株牛场分离株的检测.结果 生物信息学分析表明tcpS基因仅存在于肠炎沙门菌、鸡白痢/伤寒沙门菌和都柏林沙门菌中,该PCR方法具有高度特异性和灵敏性,可准确快速地从临床样本中筛选这3种血清型沙门菌,且对实际样本检测符合率达100％.结论 基于tcpS的PCR检测方法可准确筛选肠炎沙门菌、鸡白痢/伤寒沙门菌和都柏林沙门菌,能作为传统血清学分型的辅助方法,为沙门菌PCR鉴定方法的发展提供了优良的基因候选.