Genotypical characteristics, agr typing and toxin detection
The molecular features of the strains in study are reported in table 2.
S.aureus ATCC12598 was associated with agr type III, while ST239-III was associated with agr type I and ST228-I was associated with agr type I. δ-hemolysis production was observed in all strains with the exception of ST228-I.
Genes responsible for adhesion, such as fnb A, ica A,clf A/B, cna and sdr E (the lastbeing responsible for platelet aggregation), were present in all strains. Clone ST228-I showed a pattern of toxin genes similar to ATCC12598 (luk -PV, seg, sei, sem ), also carrying enterotoxin A and O genes. All strains showed the presence of hld , and hlg, and ST239-III carried, in addition, the hl b gene.