Purification of Type B Staphylococcal Enterotoxin.

Frea, James I. (University of Wisconsin, Madison), Elizabeth McCoy, and F. M. Strong. Purification of type B staphylococcal enterotoxin. J. Bacteriol. 86:1308-1313. 1963.-A procedure for the production and isolation of type B staphylococcal enterotoxin in yields up to 4 mg per liter of toxic culture is presented. Staphylococcus aureus S6 was grown in shake flask cultures at 37 C for 24 hr in a medium consisting of 2% Hy-Case S.F., 0.3% yeast extract, calcium pantothenate, nicotinic acid, and thiamine. Cells were removed by centrifugation and the supernatant fluid was concentrated by dialysis against polyethylene glycol. Enterotoxin was isolated from the concentrate by ethanol precipitation, gel filtration on a G-100 Sephadex column, and Sephadex-column electrophoresis. The purified toxin was identical to type B reference enterotoxin on both disc electrophoresis and Ouchterlony gel diffusion. It contained no carbohydrates, lipids, or nucleic acids, gave positive tests for protein; and contained 11.6% N. The preparation showed no coagulase, alpha-hemolysin, or deoxyribonuclease activity. Emesis in monkeys resulted when the experimental toxin was injected at the rate of 0.26 mug of N per kg of body weight.