Purification and some physicochemical properties of toxic-shock toxin

A procedure for the purification of a protein marker for the staphylococci isolated from toxic-shock syndrome patients has been developed. The purification procedure involves the removal of the toxic protein from culture supernatant fluids of toxic-shock syndrome associated Staphylococcus aureus strains FRI-1169 and FRI-1183 by batch absorption with CG-50 resin, ion-exchange chromatography on CM-Sepharose CL-6B, and gel permeation chromatography on Sephacryl S-200. The purified toxin is a simple protein with a molecular weight of 24 000 +/- 500 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The isoelectric point of the major band is 7.0 as determined by isoelectric focusing in polyacrylamide gels. The TS-toxin's reactivity with its specific antibody is not affected by tryptic digestion at pH 8.0 but is slowly reduced by treatment with pepsin at pH 4.5. The TS-toxin consists of 188 amino acid residues. Serine was shown to be the NH2-terminal amino acid residue by end-group analysis. Initial studies indicated the protein was emetic; thus tentatively it was called staphylococcal enterotoxin F. In this paper it is called TS-toxin because the emetic action in monkeys has not been confirmed.