All About Pepsin

3. Proteases

Pepsin is a type of protease that uses an aspartate carboxylic acid, such as an amino acid. Aspartic proteases, for instance, activate a water molecule and use it to sever peptide bonds, a process called hydrolysis. There are seven groups of proteases, and pepsin works alongside the serine proteases chymotrypsin and trypsin to perform digestion. Of these three proteases, pepsin is the first to activate and respond. It performs the initial breakdown in the stomach while chymotrypsin and trypsin activate in the duodenum and the small intestine, respectively.

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