Lysozyme catalytic side chain groups

In addition to the side chains that bind the substrate to the active site, there are also side chains at the active site that are responsible for catalyzing the reaction. These side chains can be acids, bases, or nucleophiles —the same kinds of species that catalyze nonbiological reactions (Section 5.11). For example, lysozyme has two catalytic groups at its active site, an acid catalyst and a nucleophilic catalyst (Figure 5.9). How these groups catalyze cleavage of the cell wall will be explained in Section 23.10, after you know more about the kind of reaction that is involved. 

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