Analysis of virulence factors in Salmonella speces

根据已报道的沙门氏菌神经毒素基因(STN-101和STN-111)序列设计特异性寡核苷酸引物，应用聚合酶链式反应(PCR)方法检测临床和食品样品中分离到的各种沙门氏菌。以包括肠道细菌在内的不同菌株作为对照。所有沙门氏菌(567株，58个血清型)均显示预期的PCR结果为阳性。另一方面，其他细菌属(30个不同种的224个菌株)没有产生这些特异引物的PCR产物，该体系的检测限分别为每1g粪便和肉末样品中1个细菌细胞，分别采用胰酶酱油肉汤和沙门氏菌增菌肉汤富集。结论：该聚合酶链式反应体系对公共卫生领域的实际应用具有一定的参考价值。

The specific oligonucleotide primers for Salmonella enerotoxin gene (stn 101 and stn 111) were designed according to the reported sequences for polymerase chain reaction (PCR) method to examine various strains of Salmonella isolated from clinical specimens and food samples. As the control, different bacterial strains including enteric bacteria were used. All of the Salmonella strains (567 strains with 58 serovar) showed positive results for the expected PCR. On the other hand, the other bacterial genera (224 strains of 30 different species) did not yield and PCR product for these specific primers.The detection limit of the PCR system was one bacterial cell per one gram of fecal and minced-meat samples using enrichment procedure by Trypticase soy broth or Salmonella enrichment broth, respectively. We concluded that this PCR system is useful for the practical application in the field of the public health.