Report of a Strain of Staphylococcus caprae with the Genes for Enterotoxin A and Enterotoxin-Like Toxin Type P

Staphylococcal enterotoxins have long been recognized as being responsible for staphylococcal food poisoning. Recently, attention has centered on their role as superantigens in exacerbating sepsis (4, 9, 12). Of the known enterotoxins, staphylococcal enterotoxin A (SEA) is one of the most commonly identified in clinical isolates (5, 9, 10). The human pathogen Staphylococcus aureus is the species most frequently associated with SEA production, although other species of Staphylococcus occasionally carry the SEA gene (3). One strain of S. caprae has been shown immunologically to produce SEA (20); however, this was not confirmed with genetic analysis. This is the first report of a S. caprae strain simultaneously carrying both the SEA gene and the staphylococcal enterotoxin-like toxin type P (SElP) gene. SElP was recently described in a study reporting the whole-genome sequencing of S. aureus strain N315 (11). The toxin produces an emetic response in Suncus murinus (the house musk shrew), but the emetic activity of SElP has not yet been tested on a primate model (13).