The Mechanism of Enzyme Action

FOR a long time two viewpoints regarding the mechanism of enzymatic activity have profoundly influenced our conceptions in this field. To Oscar Loew is due the credit for the original suggestion that the enzymes possessing atomic groups with kinetic lability are able, even at a comparatively low temperature, to perform chemical action. This suggestion was later abandoned more and more, and we now generally assume that, as in the case of heterogeneous reactions, the reactants arc adsorbed by the enzyme in order that reaction may ensue. In accordance with this we believe with Bayliss that the reaction velocity is determined by the concentration of adsorption complex, that is, reactant-enzyme, present in the system. The possibility of carrying out such reactions depends doubtlessly on certain conditions of the surface, which are also profoundly influenced by the hydrogen ion concentration.