Chymotrypsinogen

Chymotrypsinogen is the inactive zymogen precursor of chymotrypsin, a major serine protease synthesized and secreted by the exocrine pancreas [1, 7]. Upon reaching the duodenum, it is activated by trypsin-mediated proteolytic cleavage, which induces a conformational change to form the active enzyme's catalytic site [2, 11]. Chymotrypsin plays a vital role in the digestive system by catalyzing the hydrolysis of peptide bonds, specifically targeting the carboxyl side of large hydrophobic amino acids such as phenylalanine, tyrosine, and tryptophan [1, 4]. Beyond its primary digestive function, specific isoforms like chymotrypsinogen C (CTRC) are critical for regulating the activation and degradation of other pancreatic zymogens, and mutations in these genes are strongly linked to chronic pancreatitis [8, 16]. Therapeutically, chymotrypsin is administered as part of pancreatic enzyme replacement therapy for conditions like cystic fibrosis and chronic pancreatitis, and it has been investigated for its anti-inflammatory and potential anti-tumor properties [3, 12]. However, its clinical use is associated with safety concerns such as hypersensitivity reactions and, historically, increased intraocular pressure when used in ophthalmic surgery [3, 20].

Other names

ChymotrypsinZymogen of chymotrypsinChymotrypsinogen AChymotrypsinogen BChymotrypsinogen CCaldecrinPancreatic chymotrypsinogen

Acts as a serine protease that utilizes a catalytic triad consisting of Ser195, His57, and Asp102 to facilitate the nucleophilic attack and hydrolysis of peptide bonds at the C-terminal of aromatic or large hydrophobic amino acids [1, 7].