CLOTH‐BASED HYBRIDIZATION ARRAY SYSTEM FOR DETECTION OF TOXIN GENES ASSOCIATED WITH MAJOR FOODBORNE PATHOGENIC BACTERIA

Abstract

ABSTRACT A simple cloth‐based hybridization array system (CHAS) was developed for the identification of toxin genes associated with major foodborne pathogenic bacteria, including toxigenic Escherichia coli, Vibrio cholerae and Salmonella spp. Bacterial isolates were subjected to a multiplex polymerase chain reaction incorporating digoxigenin (DIG)–deoxyuridine triphosphate and primers targeting a variety of toxin genes (verotoxin, Salmonella enterotoxin, cholera toxin and heat‐labile/stable enterotoxin), followed by hybridization of the amplicons with an array of probes immobilized on polyester cloth and subsequent immunoenzymatic assay of the bound DIG label. This system provided sensitive and specific detection of the different target toxin gene markers in a variety of bacterial isolates, exhibiting the expected patterns of reactivity with a panel of bacteria having defined toxigenicity profiles. The CHAS is a cost‐effective tool facilitating the determination of the potential toxigenic profile of bacteria in the food microbiology laboratory, thus contributing valuable information to the risk‐assessment process in the microbiological analysis of foods.