What is the Role of Protonation in Enzyme Catalysis?
In enzyme catalysis, protonation and deprotonation are essential for the catalytic cycle. Enzymes have active sites with specific residues that can either donate or accept protons, thereby stabilizing transition states and intermediates. For example, in the catalytic triad of serine proteases, the histidine residue acts as a proton shuttle, facilitating the nucleophilic attack on the peptide bond.