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Jasper Sandbox 10
From Proteopedia
The Mechanism of Trypsin
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| 2age, resolution 1.15Å () | |||||||||
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| Ligands: | |||||||||
| Non-Standard Residues: | |||||||||
| Activity: | Trypsin, with EC number 3.4.21.4 | ||||||||
| Related: | 2agg, 2agi, 2ah4
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||||
Tryspin is a serine protease, whose function in the body is to hydrolyze peptide bonds of the foodstuffs we eat. Tryspin targets positively charged residues, much like chymotrypsin targets bulky hydrophobic residues and elastase targets small neutral residues. It has three important sites: histidine-57, aspartate-102, and serine-195. The mechanism for the reaction begins with a nucleophilic attack by SER-195. A tetrahedral intermediate forms, which is then decomposed into the acyl-enzyme intermediate. Water then replaces the RNH2 group, eventually binding to the C-terminus and regenerates the enzyme.
