Publisher's Synopsis
Excerpt from Influence of Certain Amino Acids Upon the Enzymic Hydrolysis of Starch: Dissertation Submitted in Partial Fulfillment of the Requirements for the Degree of Doctor of Philosophy in the Faculty of Pure Science, Columbia University
The most evident explanation of this marked temperature effect is that the amino acids preserve the enzyme in solution from the destructive influence of heat. In so far as the result of enzymic hydrolysis is concerned, increase in temperature exerts two opposite influences upon' amylolytic action. It accelerates the velocity of conversion of starch into sugar and at the same time increases the rate of deterioration of the enzyme. The second reaction being retarded by the presence of one of the decomposition products, the first effect, that is, increase in the rate of hydrolysis of the starch, becomes more noticeable. When hydrolysis continued for 60 minutes the amino acids pro duced a greater apparent activation at all temperatures until after coagulation of the enzyme had occurred than was observed for the shorter period digestions. Digestions carried out at 40�c. For periods of time from 20 minutes to 3 hours with and without glycine and tyrosine show the same increase in apparent activation with length of time of action of the amylase. This is what would be expected if the amino acid activates by protecting against deterioration, since the longer the enzyme is subjected to an injurious temperature, the greater the deterioration and consequently the more marked the activating effect in digestion mixtures in which the destruction is partially prevented. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.
