SOLVATION EFFECTS UPON THE THERMODYNAMIC SUBSTRATE ACTIVITY - CORRELATION WITH THE KINETICS OF ENZYME CATALYZED-REACTIONS .2. MORE COMPLEX INTERACTIONS OF ALPHA-CHYMOTRYPSIN WITH DIOXANE AND ACETONE WHICH ARE ALSO COMPETITIVE INHIBITORS

It is shown that the effects of the addition of various amounts of dioxane and acetone (solvent modifiers) upon the alpha-chymotrypsin-catalyzed hydrolysis of methylhippurate can be explained in terms of three factors. (A) The effects of the above modifiers on the chemical potential of the substrate. (B) The solvent modifiers dioxane and acetone also act as classical competitive inhibitors. The means of sorting out these contributions is presented. (C) The alterations of the chemical potentials or for free energies of the enzyme, enzyme-substrate complex, and/or other intermediates by the added modifiers appear to cancel out with the substrate used here.