Abstract
Staphylococcal enterotoxin A was isolated in a highly purified form by means of ionexchange resin adsorption, gel filtration, trypsinization, and ultrafiltration. Amberlite CG-50 ion-exchange resin adsorption is a convenient way to concentrate crude toxin from a large volume of culture fluid. Ultrafiltration with Amicon UM-10 is another useful means to concentrate. The molecular sieve is an efficient tool to concentrate the toxin from diluted fluid. When used in an insolubilized form, trypsin was proved to be significantly effective for eliminating α-hemolysin selectively from crude enterotoxin A. The purified sample appeared to be a single entity when examined by immunoelectrophoresis and CM-cellulose column chromatography.
The specific activity of the purified sample was 356 times as high as that of the starting material when determined on protein concentration. The yield of the sample was 40% of the starting material.