Occurrence of Enterobacteriaceae with Serological Cross Reactivity towards Salmonella spp., Shigella spp. and Vibrio cholerae in Food

Aims: This study was conducted to determine the occurrence of serologically cross-reactive enterobacteriaceae in food samples.
Place and Duration of Study: This study was conducted in Industrial Microbiology Laboratory, IFST, BCSIR, Dhaka, Bangladesh during January-November, 2013.
Methodology: 14 Enterobacteriaceae was isolated from food samples and identified. Serological reaction was determined by slide agglutination method.
Results: Among 14 isolates, 6 were identified to be Cronobacter spp., 3 to be Shigella spp., 2 to be Enterobacter spp., 2 to be Escherichia coli and 1 as Klebsiella spp. Three of the isolates belonging to Cronobacter showed extremely strong cross-reactivity with Salmonella spp., Shigella spp. and Vibrio cholerae. Other isolates gave relatively weak but significant cross-reactions. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of cell surface protein also showed similar bands in the isolates as type strains of Salmonella, Shigella and Vibrio cholerae.
Conclusion: The results indicate that Salmonella spp., Shigella spp. and Vibrio cholerae surface antigens are shared by Enterobacteriaceae present in food.