Given the task definition and input, reply with output. Given a scientific passage and an answer, generate a question for the given answer.

Passage: Pepsinogen is an inactive form of pepsin; pepsin is the active form of the enzyme. Both enzymes catalyze the hydrolysis of peptide bonds. Chymotrypsin catalyzes the hydrolysis of peptide bonds following aromatic amino acids, while trypsin catalyzes the hydrolysis of peptide bonds following lysine and arginine. Aminopeptidase catalyzes the hydrolysis of amino acids from the N-terminal end of a protein, while carboxypeptidase catalyzes the hydrolysis of amino acids from the Cterminal end of a protein. Answer: aminopeptidase
What catalyzes the hydrolysis of amino acids from the n-terminal end of a protein?