Chymotrypsinogen is a zymogen (inactive enzyme precursor) of a serine protease, chymotrypsin, produced and secreted by pancreas. It becomes active only after proteolytic cleavage in digestive tract, ensuring that protease activity is safely regulated and spatially controlled.
Chymotrypsinogen
| CAS No: | 9035-75-0 |
| EINECS No: | 232-899-3 |
| Synonyms: | Zymogen of chymotrypsin, pancreatic chymotrypsinogen A |
Product Summary
Chymotrypsinogen is an essential biological precursor for enzyme chymotrypsin, offering a safe, inactive storage form until enzymatic activity is needed. It serves as a biological model, a controlled tool for proteolysis, and an industry-grade protease precursor. Its well-characterized structure and activation mechanism make it invaluable in enzyme research and biotechnological applications.
Function
Mechanism of Action
- Zymogen activation:
- Chymotrypsinogen is converted into π-chymotrypsin by trypsin, which cleaves a specific peptide bond (between Arg15 and Ile16).
- π-Chymotrypsin then undergoes autocatalytic cleavage to become fully active α-chymotrypsin, composed of three peptide chains held by disulfide bonds.
- Enzyme function:
- Once activated, α-chymotrypsin hydrolyzes peptide bonds next to aromatic amino acids such as phenylalanine, tyrosine, and tryptophan.
- It uses a serine protease mechanism, with a catalytic triad (Ser195-His57-Asp102) facilitating nucleophilic attack on peptide bond.
Applications in Scientific Research
- Structural biology: Chymotrypsinogen is widely used as a model to study zymogen activation, protein folding, and enzyme evolution.
- Crystallography: Its high-quality crystals have been foundational in elucidating enzyme structure and activation mechanisms.
- Enzymology studies: Offers a controlled way to study time-dependent enzyme activation and kinetics.
- Educational demonstration: Common in biochemical teaching labs to demonstrate zymogen activation.
Packaging & Storage
- Available as white lyophilized powder.
- Store in an airtight container at a temperature of 2 to 8°C, protected from light.
References
- Butler JAV. 1941: On the formation of chymotrypsin from chymotrypsinogen, J Am Chem Soc. 63(11):2968–70.
- Dreyer WJ, Neurath H. 1955: The activation of chymotrypsinogen, J Am Chem Soc. 77(3):814–5.
- Hou DX, et al. 1994: Evolutionary conservation of chymotrypsinogen gene: Genomic analysis and protein modeling, J Hum Genet. 39:235–42.
- Hou DX, et al. 1993: Genomic cloning and partial characterization of human chymotrypsinogen gene, Jap J Hum Genet. 38:371–80.
- Barrett JT, Thompson LD, et al. 1965: Immunochemical studies with chymotrypsinogen A, Immunochem. 8(2):136–43.
- Gomis-Rüth SX, et al. 1995: The three-dimensional structure of the native ternary complex of bovine pancreatic procarboxypeptidase A with proproteinase E and chymotrypsinogen C, EMBO J. 14(18):4387–94.
- Lamy F, et al. 1977: Chymotrypsinogen D, a new zymogen from porcine pancreas with proelastolytic activity, Adv Exp Med Biol. 79:165–75.
- Cattani G, et al. 2021: Trypsinogen and chymotrypsinogen: the mysterious hyper-reactivity of selected cysteines is still present after their divergent evolution, FEBS J. 288(20):6003–18.
- Prahl JW, Neurath H. 1966: Pancreatic enzymes of the spiny pacific dogfish. I. Cationic chymotrypsinogen and chymotrypsin, Biochem. 5(6):2131–46.
- Mátrai G, et al. 2004: Simulation of the activation of alpha-chymotrypsin: analysis of the pathway and role of the propeptide, Protein Sci. 13(12):3139–50.
- Freer ST, et al. 1970: Chymotrypsinogen: 2.5-angstrom crystal structure, comparison with alpha-chymotrypsin, and implications for zymogen activation, Biochem. 9(9):1997–2009.
- Beres L, Sturtevant JM. 1971: Calorimetric studies of the activation of chymotrypsinogen A, Biochem. 10(11):2120–6.