Analysis of virulence factors in Salmonella speces

根据已报道的沙门氏菌内毒素基因序列，设计特异性寡核苷酸引物，用于聚合酶链反应（PCR）检测临床标本和食品中分离的沙门氏菌。作为对照，使用不同的细菌菌株，包括肠道细菌。所有沙门氏菌菌株（567株，58个血清型）均显示预期PCR阳性结果。用胰酪胨大豆肉汤或沙门氏菌增菌肉汤增菌，PCR体系的检出限分别为每克粪便和碎肉样品1个细菌细胞。该PCR体系在公共卫生领域的实际应用具有一定的价值。

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.