A simple purification method for enterotoxin F produced by Staphylococcus aureus and some properties of the toxin

Staphyloccoccus aureus enterotoxin F (SEF), which is associated with S. aureus strains isolated from toxic-shock-syndrome patients, was purified by successive chromatography on CM sephadex C-25 and gelfiltration on sephadex G-75. When tested by disc-polyacrylamide gel-electrophoresis the toxin migrated as a homogeneous protein. In SDS-polyacrylamide gel-electrophoresis three protein bands were observed. The main component had a mol wt of 23 000 and the two minor components had a mol wt less than 13 000. By iso-electric focussing a main protein band with an iso-electric point of 7.2 was obtained. The LD50 for rabbits (3-3.5 kg) by subcutaneous and intravenous application of SEF was 6 micrograms and 180 micrograms, respectively. Antibodies to SEF prepared in a sheep did not react with other staphylococcal enterotoxins (A to E).