Lord 1 has called attention to the probable importance of an increase in the hydrogen ion concentration in the pneumonic lung in inhibiting the growth of the pneumococcus and favoring enzymatic action. In this article we wish to elaborate certain aspects of the relation of the pneumococcus to changes in acidity. The hydrogen ion concentrations were determined by the colorimetric method with sta...

The growth rate responses of Escherichia coli M23 (a nonpathogenic strain) to suboptimal pH and lactic acid concentration were determined. Growth rates were measured turbidimetrically at 20 degrees C in the range of pH 2.71 to 8.45. The total concentration of lactic acid was fixed at specific values, and the pH was varied by the addition of a strong acid (hydrochloric) or base (sodium hydroxide...

1. Quantitative data are given on the effect of changes in hydrogen ion concentration and of salt solutions of high concentration on certain immune precipitates obtained at lower salt concentration. 2. Advantage is taken of the shift in reaction equilibrium brought about by the salt in the case of pneumococcus carbohydrate-anti-carbohydrate precipitates to enable the preparation, in a single st...

A series of diethylmethyl(2-methoxyethyl)ammonium (DEME)-based ionic liquids were prepared using bis(perfluoroalkanesulfonyl)amide (C(n)F(2n+1)SO(2))(2)N anions with different perfluoroalkyl chain lengths (n = 0, 1, 2, 3, and 4), and the influence of the structural variation on their thermal, ion-diffusive (ionic conductivity and viscosity), ion-concentration (molar concentration and ion associ...

1. Evidence is presented that pepsin is a univalent acid with a value for pK of 6.85 (or a base, with pK 7.39). 2. The autodestruction of the pepsin is shown to be dependent in part upon an instantaneous irreversible change occurring in the ionized form of the enzyme (if it be an acid) or in the unionized form (if it be a base). 3. A further progressive autodestruction of pepsin at any given hy...