Polymerase chain reaction for salmonella virulence–associated plasmid genes detection: a new tool in salmonella epidemiology

Abstract

SUMMARYThe important role of plasmid genes in assessing virulence for BALB/c mice in salmonella, and the difficulty of using standard techniques to detect them, led us to develop a detection method by gene amplification.One hundred and forty-three strains (71 serovars) of salmonella and 35 strains of other species were tested using specific oligonucleotide primers. The amplification products were identified by a specific oligonucleotide probe. Forty-nine salmonella strains from ten serovars (S. abortus ovis, S. choleraesuis, S. dublin, S. enteritidis, S. gallinarum/pullorum, S. hessarek, S. typhimurium, S. IIIa 48: Z4, Z23, S. IV43:z4, Z23: -, S. V 28: a: -) produced a positive and specific response.Because of various origins of the strains possessing the gene sought and the diversity of the responses, both from one serovar to another and in the same serovar, this search has its place among the epidemiological markers in general use. This method appears well suited to the research and detection of plasmid genes associated with mouse virulence in salmonella.

PCR Detection of Salmonella enterica Serotype Montevideo in and on Raw Tomatoes Using Primers Derived from hilA

“…Various sets of primers for PCR detection of salmonellae have been described previously (14,18,19,24,29,30,31). Gooding and Chaudary (17) recently conducted a comparison study of primers with different test panels of Salmonella and non-Salmonella strains and different PCR conditions and found that there were variations with regard to the specificities of the primers.…”

“…One of the most promising methods for detecting salmonellae is based on the PCR, which combines simplicity with specificity and sensitivity for detecting the pathogens in food. Several PCR assays have been developed by targeting various Salmonella genes, such as invA (29,31), 16S rRNA (19), agfA (14), and viaB (18), and virulence-associated plasmids (24,30). These PCR assays are used mainly for detecting salmonellae in poultry, meat, and milk samples (5,7,13,22).…”

Detection and Identification of Salmonella Typhimurium in Bovine Diarrhoeic Fecal Samples by Immunomagnetic Separation and Multiplex PCR Assay

“…On the other hand, several PCR assays have been developed to detect Salmonella at genus and serotype level on different areas of the genome. Selected regions that have been studied singly or combined for PCR assay include agf A, fim A, hin , H‐li, iag AB , IS 200, iro B, mkf A, omp C, spv R , via B, (Cano et al., 1993; Fluit et al., 1993; Mahon and Lax, 1993; Way et al., 1993; Rexach et al., 1994; Chevrier et al., 1995; Hashimoto et al., 1995; Cohen et al., 1996; Doran et al., 1996; Kwang et al., 1996; Baumler et al., 1997). Some of these methods have limitation.…”

“…Hin and H‐li genes are specific for motile strains not for Salmonella Gallinarum and Salmonella Pullorum (Way et al., 1993) . Amplification of mkf A showed positive results only from 10 Salmonella serovars (Rexach et al., 1994). For specific identification of S. Typhimurium target genes such as florfenicol (flo), invasion ( inv‐ A), integron (int ) and, virulence ( spv C) have been used (Bolton et al., 1999; Khan et al., 2000; Ebner and Mathew, 2001).…”

PCR detection of Salmonella spp. in Fresh Vegetables and Feed

“…Constant variations in dietary habits and agronomic practices, the increase in the consumption of vegetables that are consumed raw along with increased importation of fresh produce supposedly contribute to increase in the number of outbreaks associated with vegetables and animal feed of vegetable origin (Altekruse, Cohen, & Swerdlow, 1997). Salmonella outbreaks have been linked to tomatoes (Centers for Disease Control and Prevention, 1993), seed sprouts (Mahon et al, 1997;O'Mahony et al, 1990), watermelons (Blostein, 1991;Centers for Disease Control and Prevention, 1979;Centers for Disease Control and Prevention, 1979), and animal feeds (Gooding & Choudary, 1999;Rexach, Dilasser, & Fach, 1994). Disposal of treated wastewater for agricultural irrigation simultaneously solves water shortage problems and reduces potential environmental contamination.…”