期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1986
卷号：83
期号：3
页码：649-653
DOI：10.1073/pnas.83.3.649
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：We present a combined quantum/molecular mechanical study of the trypsin-catalyzed hydrolysis of a specific tripeptide substrate, including the entire enzyme in the calculation, as well as 200 H2O molecules. The results illustrate how the enzyme and nearby H2O molecules stabilize the ionic intermediates in peptide hydrolysis, such that the reaction is calculated to have a barrier that is significantly smaller than the calculated and experimental base-catalyzed barrier of formamide hydrolysis in aqueous solution. This enables us to understand how serine proteases increase the rates for reactions that take place in their active sites, compared to the corresponding rates for analogous solution reactions.
