aspartic-type peptidase activity

Definition

Target type: molecularfunction

Catalysis of the hydrolysis of peptide bonds in a polypeptide chain by a mechanism in which a water molecule bound by the side chains of aspartic residues at the active center acts as a nucleophile. [GOC:mah, https://www.ebi.ac.uk/merops/about/glossary.shtml#CATTYPE]

Aspartic-type peptidase activity refers to the catalytic mechanism employed by a class of enzymes known as aspartic peptidases. These enzymes cleave peptide bonds within proteins, playing a crucial role in protein degradation and processing. Their catalytic mechanism relies on two aspartic acid residues located within the active site of the enzyme. These residues, often termed Asp1 and Asp2, act in concert to facilitate the hydrolysis of the peptide bond. The mechanism involves the following steps: 1) The substrate peptide binds to the active site of the enzyme, positioning the scissile bond (the peptide bond to be cleaved) between the two aspartic acid residues. 2) Asp1 acts as a general base, abstracting a proton from a water molecule. 3) The activated water molecule then attacks the carbonyl carbon of the scissile bond, forming a tetrahedral intermediate. 4) Asp2, acting as a general acid, donates a proton to the leaving group, the amino group of the peptide bond. 5) The tetrahedral intermediate collapses, breaking the peptide bond and releasing the two peptide fragments. The two aspartic acid residues within the active site work in tandem to facilitate the hydrolysis reaction. Asp1 activates the water molecule for nucleophilic attack, while Asp2 stabilizes the transition state and facilitates the departure of the leaving group. This concerted action of the two aspartic acid residues is essential for the catalytic activity of aspartic peptidases.'
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Proteins (1)

Compounds (20)