Purification of exfoliative toxin produced by Staphylococcus hyicus and its antigenicity

We previously reported the isolation of an exfoliative toxin from culture filtrates of Staphylococcus hyicus (shET) and reproduction of exfoliation in piglets injected with partially purified shET. In this study, we purified shET and compared the biological and physicochemical properties of shET and Staphylococcus aureus exfoliative toxin (sETA and sETB). shET was purified by ammonium sulfate precipitation, DEAE-cellulofine A-500 column chromatography, Sephadex G-75 gel filtration, and polyacrylamide gel electrophoresis (7.5% polyacrylamide). Purified shET (p-shET) did not cause exfoliation of the epidermis in suckling mice but did cause exfoliation in 1-day-old chickens, whereas sETA and sETB produced by S. aureus caused exfoliation in suckling mice but not in 1-day-old chickens. The molecular mass of p-shET was determined as 27 kDa by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. p-shET did not show any cross-reactivity with sETA and sETB in Western immunoblotting analysis or the immunodiffusion test.