Role of water in enzyme kinetics

In many cases, water turns into a proton and a hydroxyl anion and the A-B bond shown above breaks to make A and B . Therefore, a pair of electrons needs to be moved around, and electrostatics of the medium must play an important role. We discuss specific examples helow. 

Our second example is provided by proteases, which are another type of hydrolases that catalyze the hydrolysis of peptide bonds in proteins. A general reaction scheme for proteases is shown in Reaction 7.1. 

Interestingly, there are many such examples of proteases that exist in nature, such as, trypsin, chymotrypsin, elastase, thrombin, subtilisin, plasmin, pepsin, chymosin, cathepsin D, renin, and HIV-1 protease, etc. To illustrate the direct participation of water in the digestive mechanism we show another example of proteolysis 

An essential chemical for life processes water in biological functions 

In addition to its direct participation in the bond-cleavage process, the localized water molecule present in the catalytic active site can cause significant stabilization of the transition state formed in the middle course of a reaction. 

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