Chymotrypsin B (CTRB) (CTRB)

Chymotrypsin B is a major digestive serine protease synthesized in the pancreas as an inactive zymogen, chymotrypsinogen, and subsequently activated by trypsin in the duodenum (UniProt P17538). Its primary biological function is the hydrolysis of dietary proteins, specifically cleaving peptide bonds on the carboxyl side of aromatic amino acids like phenylalanine, tyrosine, and tryptophan (NCBI Gene 1504). In clinical practice, chymotrypsin activity is a key indicator of exocrine pancreatic function, with low levels in feces serving as a biomarker for pancreatic insufficiency (PubMed PMID: 2461112). Pathologically, premature activation of chymotrypsin within the pancreas is associated with the development of acute pancreatitis (StatPearls: Pancreatitis). While recombinant human chymotrypsin is frequently used in laboratory settings to study proteolytic mechanisms and screen for protease inhibitors, the enzyme itself is also administered therapeutically to aid digestion in patients with cystic fibrosis or chronic pancreatitis (PubChem CID 10129898).

Other names

Chymotrypsinogen BCTRB1CTRB2Serine proteaseChymotrypsin-like protease

Serine protease that catalyzes the hydrolysis of peptide bonds with a preference for aromatic or large hydrophobic amino acid residues at the P1 position.