Development and use of PCR primers for the investigation of C1, C2 and C3 enterotoxin types of Staphylococcus aureus strains isolated from food-borne outbreaks.

Staphylococcus aureus is a major food-borne pathogen in many countries. Enterotoxins produced by S. aureus strains include staphylococcal enterotoxins (SEs) A, B, C, D, E and G, H, I, etc. For SEC, in addition to the three major SEC subtypes, i.e., SEC1, C2 and C3, other molecular variants may exist. Although the detection methods and the distribution of SEA, B, C, D, E types of S. aureus in staphylococcal infections or food-borne outbreaks have been well documented, the differentiation method and the distribution of SEC subtypes in staphylococcal infections are rarely reported. In this study, four polymerase chain reaction (PCR) primers used in pairs (ENTC1/ENTCR, ENTC2/ENTCR and ENTC3/ENTCR) for the specific detection of SEC1, C2 and C3 genes of S. aureus strains were developed. When 39 SEC S. aureus strains isolated from fecal samples of randomly selected diarrheal patients associated with food-borne outbreaks in central Taiwan in 6 years (1995-2000) were analyzed, it was found that the major SEC subtypes for these S. aureus strains were SEC2 and C3.