Related Experiment Video
Updated: Sep 9, 2025
An Allelotyping PCR for Identifying Salmonella enterica serovars Enteritidis, Hadar, Heidelberg, and Typhimurium
Published on: July 22, 2011
Rapid detection of Salmonella Enteritidis and S. Typhimurium serotypes and characterization of flagellar variants
Hans Fröder1, André Bittencourt Lorusso2, Gustavo Sganzerla Martinez3
1Laboratory of Microbiology (Unianálises), University of Vale do Taquari, Lajeado, Rio Grande do Sul, Brazil; Laboratory of Agrifood Research and Innovation (LAPIAgro), Graduate Program in Animal Science, Pontifical Catholic University of Paraná, Curitiba, Paraná, Brazil.
Abstract:
The wide diversity of Salmonella serotypes poses challenges for traditional serotyping methods, which are labor-intensive and unsuitable for high-throughput testing, particularly in food safety contexts. Hence, this study aimed to develop and validate a real-time PCR method for detecting Salmonella spp., identifying the major public health serotypes (S. Enteritidis and S. Typhimurium), and differentiating monophasic S. Typhimurium variants. The method demonstrated high specificity and sensitivity, with 100 % inclusivity and 96.8 % exclusivity. Novel primers targeting fljB-hin allowed effective differentiation of monophasic variants, while dual biomarkers (STM4492 and STM2755) improved S. Typhimurium detection accuracy. Compared to conventional serotyping, the method showed excellent concordance (κ = 1.00, p < 0.01) and reduced turnaround time to under 2 h without requiring post-PCR processing. The inclusion of short amplicons (<200 bp) ensures efficiency and compatibility with fast cycling protocols. This validated, open-access assay offers a reliable and cost-effective molecular alternative for food safety monitoring, especially in settings with limited infrastructure.
