Chymotrypsin (CTR)

Chymotrypsin is a digestive enzyme that can perform proteolysis. Chymotrypsin preferentially cleaves peptide amide bonds where the carboxyl side of the amide bond is a tyrosine, tryptophan, or phenylalanine. These amino acids contain an aromatic ring in their sidechain that fits into a """hydrophobic pocket""" of the enzyme.The hydrophobic and shape complementarity between the peptide substrate P1 sidechain and the enzyme S1 binding cavity accounts for the substrate specificity of this enzyme.Chymotrypsin also hydrolyzes other amide bonds in peptides at slower rates, particularly those containing leucine at the P1 position. Chymotrypsin is synthesized in the pancreas by protein biosynthesis as a precursor called chymotrypsinogen that is enzymatically inactive.