Toronto, Ontario. The remaining str

Toronto, Ontario. The remaining strains were from the culture collection
of the Health Canada, Bureau of Microbial Hazards, Ottawa, Ontario. The
presence of STEC virulence genes stx1, stx2, eae, and EHEC hlyA was
determined by the PCR protocol of Paton and Paton (2003). The cultures
were stored as frozen glycerol stocks. For experimental use, the cultures
were streaked onto brain heart infusion (BHI) agar (Difco, BD, Sparks,
MD) and incubated at 37 °C for 24 h.