Question

Pepsin is a protein digesting enzyme . Then why it does not digest other enzymes instomach as enzymes are made up of proteins??

Answer 1

Enzymes are specific in their action i.e they act on particular substrate with specific structure only and accelerate either its breakdown or making. Different enzymes breakdown different substrates and proteins. The active site of enzyme binds to the substrate at binding site and results in the breaking of its bonds and formation of product. The pepsin specifically acts on the proteins present in the food and breaks them into peptides. Thus, it cannot act on other enzymes as they lack binding site for binding of this enzyme.