Serine protease trypsin-1 (Trypsin-1)

Serine protease trypsin-1 is a digestive enzyme predominantly synthesized in the pancreas and secreted into the small intestine, where it plays a critical role in hydrolyzing peptide bonds following lysine or arginine residues in dietary proteins[5][6]. Trypsin-1 is produced as an inactive zymogen (trypsinogen) and is activated by enteropeptidase-mediated cleavage in the duodenum[2]. The enzyme's catalytic activity relies on a conserved catalytic triad of serine, histidine, and aspartate, enabling a highly efficient nucleophilic hydrolysis mechanism[3][5]. Trypsin's substrate specificity is determined by a negatively charged aspartate in the S1 pocket, favoring cleavages after basic residues[1][6]. Beyond digestion, aberrant trypsin activity is linked with pancreatitis due to unwanted activation of trypsinogen within the pancreas. Recombinant and pharmaceutical inhibitors of trypsin have clinical or experimental uses in pancreatitis and blood clotting disorders. Trypsin-1 is also a model system in enzymology and has been extensively characterized structurally and mechanistically[7].

Other names

TrypsinTrypsin-1Cationic trypsinPRSS1 (gene/protein identifier)Pancreatic trypsin-1

Irreversible inhibition of the active serine residue (e.g., by drugs like aprotinin, DFP). Competitive binding to the active site and S1 pocket (e.g., benzamidine). Zymogen inhibition/stabilization (e.g., by specific protein inhibitors). Allosteric regulation by endogenous inhibitors.