Molecular markers for the detection of pathogenic and food poisoning potential of methicillin resistant Staphylococcus aureus isolated from wounds of hospitalized patients.

Pathogenic strains of Staphylococcus aureus are mostly resistant to methicillin and they can cause severe infections. The current study was planned to assess the food poisoning potential of pathogenic, methicillin resistant Staphylococcus aureus by molecular detection of enterotoxin A (Eta) gene. A total of 100 septic wound samples from patients admitted in surgical ward (n=50) and burn unit (n=50) of Mayo Hospital Lahore were collected aseptically. These samples were processed primarily for bacterial growth on nutrient agar and purified on mannitol salt agar where twenty (20) samples showed pin-point colonies with yellow discoloration of media. Moreover, isolates were further characterized on the basis of microscopic appearance and biochemical assays where fourteen (14) isolates were declared Staphylococcus. DNA of these isolates were subjected to 16S rRNA gene amplification and sequences of S. aureus were submitted to NCBI GenBank viz., MW344063.1, MW341438.1, MW344064.1, MW344065.1, MW341439.1, MW341440.1, MW345971.1, MW345972.1, MW345973.1, MW716458.1. All the isolates (n=10) demonstrated molecular confirmation of pathogenicity and methicillin resistance by amplification of Coa and mecA gene. Out of these ten isolates, three amplified enterotoxin A (Eta) gene were confirmed. It is concluded that enterotoxin A of S. aureus which causes food poisoning is present in pathogenic, methicillin resistant S. aureus isolated from various wounds infections.