ABSTRACT:
Staphylococcus enterotoxins (SEs) are the main etiological agents of staphylococcal food poisoning. They were classified by serological criteria into 5 major groups and recently many more groups were identified. Staphylococcus enterotoxins (SEs) are pyrogenic toxins of the super-antigen family. Therefore to ensure food safety, it is important to detect and quantify the toxin genes to confirm the presence of enterotoxigenic S. aureus in any food samples. In this study, we have developed a multiplex PCR method to profile major toxin genes such as seB, seD, seE, seI and seM of Staphylococcus aureus using reference strains as well as some food isolates. The sensitivity of the single target and mixture of toxin gene targets were tested from five-fold serially diluted respective genomic DNA samples. The single PCR and multiplex PCR assays can successfully amplify the genomic DNA when used template as low as 4.5 pg/µl and 900 pg/µl respectively. Further these primers were validated on other species including target-negative reference strains as well as other gram positive/ negative reference strains. Among tested food isolates, 66% of them found to be positive for seB and 53% of the food isolates found to have seB and seE genes together. This method is highly suitable for convenient toxin gene profiling and to detect the presence of enterotoxigenic S. aureus.