The leakage of cations and amino acids from Staphylococcus aureus exposed to moist heat, phenol and dinitrophenol.

Abstract

Summary.The leakage of K+, Na+ and amino acids from Staphylococcus aureus in an aqueous solution was studied at temperatures between 37 and 60°. The rate of efflux of K+ was temperature dependent. Above 50° an initial rapid loss of K+ was followed by a secondary and more prolonged period of efflux. 2.4‐Dinitrophenol enhanced the initial loss of K+, but not of amino acid, at all temperatures studied. Phenol, at a concentration which did not influence leakage at 37°, caused an increase in the K+ and amino acid losses at high temperatures. It also increased inactivation rates of the organism at all temperatures studied, while dinitrophenol was lethal only at lower temperatures. The importance of leakage to thermally‐induced inactivation of Staph. aureus is discussed.