Functional Word in a Protein

III. Syntax and Energetics

Abstract

Trypsin catalysis that was analyzed by the DEV model is discussed from the standpoint of energetics. In trypsin, the nucleophilic activity of 177-S is enhanced by interaction with 40-H and 84-D, and the steric strain that will be caused by many kinds of structural fluctuation is gradually accumulated and stored as the internal energy of trypsin. A small amount of energy exerts the each fluctuation, which arises in a mild physical condition. We call this process a unit process. Such unit process consequently leads to the accumulation of free energy as well as to the activation of enzymatic reaction. The sophisticated nature of bio-catalysis is also discussed.