Research: Rapid detection of Salmonella enterica serovar Typhimurium DT104 strains by the polymerase chain reaction
Infection with Salmonella enterica is a major public health concern in developed countries, and multidrug-resistant strains have become increasingly prevalent. S. enterica serovar Typhimurium DT104 (DT104) strains are prevalent in livestock in Japan and include numerous strains of multidrug-resistant S. enterica. Epidemiological analysis of these strains is critical for both agriculture and public health; however, diagnostic tests for these strains have yielded inconsistent results.
Researchers developed a rapid, simple, and inexpensive polymerase chain reaction test to detect multi-drug resistant DT104 strains. Researchers designed primers specific to the prophage ST104 sequence encoded by DT104 strains and assessed the specificity of these primers by assaying a panel of 50 S. enterica isolates. Amplification products of the expected size were generated from the genomes of each of the DT104 strains; however, the ST104 primers failed to amplify products from non-DT104 strains of S. enterica serovar Typhimurium or other S. enterica serovars. Furthermore, a probe generated using the ST104 primers detected a restriction fragment encoding the ST104 region of DT104 by Southern hybridization.
The ST104 primers exhibit specificity to DT104 strains and are suitable for epidemiological applications. PCR analysis with ST104 primers is an inexpensive, rapid, and simple technique for detecting DT104 strains in epidemiological applications. While gene sequences similar to ST104 may exist in non-DT104 strains of S. enterica Typhimurium, our PCR method may facilitate future studies endeavoring to screen for specific phage types.
© 2015 Yukawa et al.