Description
mericon Pathogen Detection Assays are a suite of kits for the target-specific detection of bacterial pathogen DNA in food, animal feed, and pharmaceutical products. All of the assays use the same real-time PCR-based protocol. They are part of the comprehensive QIAGEN food safety testing portfolio, which also features dedicated sample preparation kits and assays for ingredient authentication. mericon assays perform optimally on the Rotor-Gene Q, but have also been validated for block thermal cyclers.
mericon Campylobacter spp Kit The mericon Campylobacter spp Kit is for the specific detection of several Campylobacter subspecies in enrichment cultures of food and animal feed samples. The assay can detect as few as 10 copies of Campylobacter DNA in a reaction and it exhibits high specificity for pathogens this genus. In an experiment using 2500 copies of the tested DNA, no cross-reactivity was observed with other pathogens (see the table "Results of mericon Campylobacter spp Kit cross-reactivity study"). Results of mericon Campylobacter spp Kit cross-reactivity study Pathogen Result Pathogen Result Campylobacter jejuni + Campylobacter coli + Campylobacter lari + Campylobacter upsaliensis + Salmonella abony – Staphylococcus aureus – Clostridium perfringens – Escherichia coli – Legionella erythra – Yersinia enterocolitica – Legionella pneumophila – Listeria monocytogenes – Bacillus cereus – Cronobacter sakazakii – Shigella flexneri – mericon Cronobacter spp Kit The mericon Cronobacter spp Kit is for the specific detection of Chronobacter subspecies in enrichment cultures of food and animal feed samples. Due to a recent change in taxonomy and according to regulation of the EU Commission (365/2010) the name Cronobacter spp replaces Enterobacter sakazakii. The assay can detect as few as 10 copies of Cronobacter DNA in a reaction and it exhibits high specificity. In an experiment using 2500 copies of the tested DNA, no cross-reactivity was observed with other pathogens (see the table "Results of mericon Cronobacter spp Kit cross-reactivity study"). Results of mericon Cronobacter spp Kit cross-reactivity study Pathogen Result Pathogen Result Cronobacter sakazakii + Cronobacter dubliensis + Cronobacter turingensis + Cronobacter malonatus + Cronobacter muytjensii + Legionella pneumophila – Campylobacter jejuni – Listeria monocytogenes – Campylobacter coli – Salmonella abony – Campylobacter lari – Shigella flexneri – Campylobacter upsaliensis – Yersinia enterocolitica – Staphylococcus aureus – Clostridium perfringens – Bacillus cereus – Escherichia coli – Legionella erythra – VTEC stx1/2 – mericon Quant Legionella spp Kit The mericon Quant Legionella spp Kit is for the specific detection and quantification of several Legionella species in water after concentration (e.g., by filtration). The assay can detect as few as 10 copies of Legionella DNA in a reaction and it exhibits high specificity for pathogens of that genus. In an experiment using 2500 copies of the tested DNA, no cross-reactivity was observed with other pathogens (see the table "Results of mericon Quant Legionella spp Kit cross-reactivity study"). Results of mericon Quant Legionella spp Kit cross-reactivity study Pathogen Result Pathogen Result Legionella pneumophila + Legionella erythra + Legionella adelaidensis + Legionella feeleii + Legionella impletisoli + Legionella jordanis + Legionella israeliensis + Legionella tucsonensis + Legionella worsleinsis + Legionella beliardensis + Legionella spiritensis + Legionella lansingensis + Legionella brunensis + Legionella drozanskii + Legionella geestiana + Legionella nautarum + Legionella santicruci + Legionella shakespeare + Salmonella abony – Bacillus cereus – Clostridium perfringens – Campylobacter jejuni – Escherichia coli – Yersinia enterocolitica – Staphylococcus aureus – Listeria monocytogenes – Shigella flexneri – Cronobacter sakazakii – mericon Salmonella spp Kit The mericon Salmonella spp Kit is for the specific detection of several Salmonella subspecies in enrichment cultures of food and animal feed samples. The assay can detect as few as 10 copies of Salmonella DNA in a reaction and it exhibits high specificity for pathogens of this genus. In an experiment using 2500 copies of the tested DNA, no cross-reactivity was observed with other pathogens. mericon Vibrio triple Kit The mericon Vibrio triple Kit is for the specific detection of Vibrio vulnificus, Vibrio parahaemolyticus, and Vibrio cholerae in enrichment cultures of food and animal feed samples. The assay can detect as few as 10 copies of Vibrio vulnificus, Vibrio parahaemolyticus, and Vibrio cholerae DNA in a reaction and exhibits high specificity. In an experiment using 2500 copies of the tested DNA, no cross-reactivity was observed with other pathogens (see the table "Results of mericon Vibrio triple Kit cross-reactivity study"). Pathogen Result Pathogen Result Vibrio vulnificus + Staphylococcus aureus – Vibrio parahaemolyticus + Bacillus cereus – Vibrio cholerae + Salmonella abony – Vibrio alginolyticus – Clostridium perfringens – Vibrio furnissii – Shigella flexneri – Legionella pneumophila – Escherichia coli – Campylobacter jejuni – Cronobacter sakazakii – Listeria monocytogenes – Yersinia enterocolitica – mericon E. coli O157 Detection Kits The mericon E. coli Screen Plus Kit is designed for the qualitative detection of the E. coli serotype O157 and E. coli virulence genes intimin (eae) and Shiga toxin-like proteins (stx1 and stx2). The presence of eae and stx1/stx2 suggests that further investigation into the E. coli O-serotype O157, or the non-O157 O-serotypes (O26, O45, O103, O111, O121, and O145) is required in food and animal feed samples after enrichment. The assay can detect as few as 10 copies of E. coli DNA in a reaction and it exhibits high specificity for pathogens of this species. In an experiment using 2500 copies of the tested DNA, no cross-reactivity was observed with other pathogens (see table "Results of mericon E. coli O157 Screen Plus Kit cross-reactivity study "for exclusivity/inclusivity data). The mericon E. coli STEC O-Type Kit exhibits high specificity for E. coli strain O157:H7, O26, O45, O103, O111, O121, and O145. The kit was tested against an extensive inclusivity panel of E. coli O157:H7 and non-O157:H7 serotype strains, and an exclusivity panel of other E. coli and non- E. coli strains. All tested O157:H7 and non-O157:H7 serotype strains (O26, O45, O103, O111, O121, and O145) were successfully detected and no cross-reactivity was observed with other pathogens using 2500 copies of tested DNA.
Detection of pathogens in food testing using real-time PCR is based on the amplification of a specific region of the relevant pathogen genome. The amplified product is detected using target-specific fluorescent probes that bind to it. As the PCR product accumulates, there is an increased fluorescent signal from the bound probes. Monitoring the fluorescence intensities during the PCR run (i.e., in real time) allows the detection of the accumulating PCR product without having to re-open the reaction tubes afterward. mericon PCR Assays include an internal control to control potential inhibition. This aids in the straightforward interpretation of the results (see the table "Summary of possible PCR outcomes"). Summary of possible PCR outcomes Internal control amplified Tested DNA amplified Meaning + + Sample is positive for the target DNA + – Sample is negative for the target DNA – – PCR failed due to inhibition The PCR primer set for each assay is highly specific and targets a unique and conserved region of the tested pathogen genome that has been bioinformatically and experimentally verified.
DNA is extracted from an enrichment culture of a sample of food or animal feed using a dedicated sample preparation kit. The mericon Bacteria Kit is for the isolation of bacterial DNA from Gram-negative bacteria. The mericon Bacteria Plus Kit is for the isolation of bacterial DNA from Gram-positive bacteria. The isolated, pure bacterial DNA is assayed using a streamlined real-time PCR protocol that returns results in 73 minutes on QIAGEN's Rotor-Gene Q. The protocol has also been validated for use on other thermal block cyclers. The results are displayed as easy-to-interpret PCR curves.
