Studies on the Solubility of Pneumococcus in Saponin

Abstract

The author has shown previously that cholesterol sensitizes pneumococci to lysis by saponin. Additional evidence is brought to show that a saponin-sterol union causes the lysis. Affinity for sterols is a characteristic of the group of saponins. Cholesterol sensitizes the pneumococcus to various members of the saponin group. Ergosterol also is capable of effecting sensitization. Ultraviolet irradiation of ergosterol causes loss in sensitizing activity in parallel with loss in affinity for saponin.