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Updated: Aug 8, 2026

The Importance of Correct Protein Concentration for Kinetics and Affinity Determination in Structure-function Analysis
Published on: March 17, 2010
Probing structure-function relationships of serine hydrolases and proteases with carbamate and thiocarbamate
1Department of Chemistry, National Chung-Hsing University, Taichung, 402, Taiwan. gilin@dragon.nchu.edu.tw
Abstract:
Benzene-1,3-di-N-n-octylcarbamate (1), benzene-1-hydroxyl-3-N-n-octylcarbamate (2), benzene-1,3-di-N-n-ocztylthiocarbamate (3), and benzene-1-hydroxyl-3-N-n-octylthiocarbamate (4) are synthesized from 1,3-benzene-diol and are characterized as the pseudo-substrate inhibitors of acetylcholinesterase, butyrylcholinesterase, cholesterol esterase, lipase, trypsin, and chymotrypsin. For these six enzyme inhibitions by 1-4, the pKi values are linearly correlated with their log ki values - Brønsted plots. Therefore, 1-4 inhibit these enzymes through a common mechanism. Moreover, both pKi and log ki values for the inhibitions by 1,3, and 4 are linearly correlated with both pKi and log ki values for the inhibitions by 2, respectively. Thus, the pKi values for the inhibitions by 2 are defined as the nucleophilicity constants of these enzymes (nenzyme). The log k2 values for the inhibitions by 1-4 are also linearly correlated with the nenzyme values. Therefore, the nucleophilicity for serine hydrolases and proteases toward 1-4 also applies the Swain-Scott correlations.
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