STAPHYLOCOCCAL TOXINS: III. PARTIAL PURIFICATION AND SOME PROPERTIES OF δ-LYSIN

Abstract

A method is described by which δ-lysin may be separated from α-lysin and enzymes present in crude preparations. The procedure consists of precipitation of lysin from crude extracts under controlled conditions of ethanol concentration, temperature, and pH, followed by extraction of 5-lysin from the precipitate with 75% ethanol in saline-phosphate buffer, pH 6.8. Evidence is presented which indicates that crude δ-lysin consists of two fractions: one stable to heating at 60 °C and another rapidly inactivated under these conditions. Heat-stable δ-lysin may be freed of contaminating α-lysin by heating crude preparation at 60 °C for 15 minutes. δ-Lysin is retained by ultrafine sintered-glass filters which permit passage of α-lysin.