Detection of Salmonella enterica serovar Montevideo in food products using specific PCR primers developed by comparative genomics

Abstract

In the present study, primer-probe sets for the detection of Salmonella enterica and S. enterica serovar Montevideo were developed based on comparative genomics. Genomic information of 706 strains of S. enterica, including 23 strains of serovar Montevideo, was retrieved from National Center for Biotechnology Information (NCBI) RefSeq and analyzed by the panX program. The phylogenetic tree of core genes indicated that 20 strains of Montevideo were clearly separated from the other S. enterica strains. After validation with the NCBI database, genes for the detection of S. enterica and S. Montevideo were selected and designated and primer-probe sets were developed targeting the genes. The developed primer-probe sets displayed high sensitivity and selectivity when 110 strains, including 86 S. enterica and 24 non-S. enterica species, were tested. Moreover, the detection sensitivity was not affected by the presence of interference materials such as Luria-Bertani medium, buffered peptone water, tryptic soy broth, phosphate-buffered saline, sheep blood, tomato, and chicken. Applicability in food samples were identified with tomato, raw chicken meat, red pepper, and black pepper. PCR analysis based on the suggested primer-probes sets showed higher detection efficacy compared to the conventional selective media in red and black pepper samples.