PARICHAT PHUMKHACHORN* AND PONGSAK RATTANACHAIKUNSOPON
Abstract
The detection of Salmonella enterica subsp. enterica serovar Typhi (S. Typhi) and S. enterica subsp. enterica serovar Paratyphi A, B and C (S. Paratyphi A, B and C) by microbiological and serological methods has labor intensive, complicated, and time consuming. To overcome such drawback, this study proposed a PCR based method for the specific detection of S. Typhi, S. Paratyphi A, B and C. The multiplex PCR employed four primer pairs including ivaB-f/ivaB-r, pBPm23-f/pBPm23-r, SSPAI-F2/SSPAI-R2 and STY1599- f/STY1599-r that targeted the viaB region, the SPAB_01124 gene, the intergenic region between SSPA1723a and SSPA1724 and the STY1599 gene, respectively. By using the multiplex PCR, two (203 bp and 599 bp), one (300 bp), one (384 bp) and one (599 bp) amplicons were produced from the genomic DNA of S. Typhi, S. Paratyphi A, B and C, respectively. This method was shown to specifically detect those Salmonella serovars in an artificially contaminated food model. When further differentiation between a sample contaminated with S. Typhi and that co-contaminated with S. Typhi and S. Paratyphi C was required, a duplex PCR was performed by using the primer pairs ivaB-f/ivaB-r and CsPcSC4352-F/CsPcSC4352-R.