Occurrence of toxin genes among different agr groups of Staphylococcus pseudintermedius isolates from dogs with skin lesions

Staphylococcus pseudintermedius contains several virulence factors including various toxins. The accessory gene regulator (agr) system in S. pseudintermedius is responsible for controlling and coordinating the production of virulence factors and regulating many factors of colonisation and pathogenicity. The purpose of this study was to determine the frequency of toxin-producing genes as well as the variety of agr in S. pseudintermedius isolated from skin lesions of dogs. Swab samples of sick dogs were obtained and tested for detecting the mentioned bacterium using both phenotypic and molecular assays. Then, the frequency of virulence genes and agr types were determined by multiplex PCR method. S. pseudintermedius was recovered in 37 of the 50 tested samples. Among the studied genes the most common toxin producing determinants were siet (89.18%), lukF (75.67%), and lukS (59.45%). However, the seC gene was only detected in 18.91% of studied isolates. Additionally, the isolates with agr type I (59.45%) were significantly more common than other agr types in diseased dogs, followed by agrIV (24.32%), and agrIII (16.21%). Morover, isolates belonging to the agrI group had greater toxin production ability. In conclusion, the frequent occurrence of toxin producing genes in S. pseudintermedius obtained from dogs with skin lesions, indicates that these toxins may play a significant role in the pathogenesis of infection among domestic animals.