omega peptidase activity

Definition

Target type: molecularfunction

Catalysis of the cleavage of non-standard peptide bonds releasing substituted amino acids such as pyroglutamate or cleave isopeptide bonds, such as many deubiquitinating enzymes. [EC:3.4.19.-, PMID:20157488, PMID:9920379]

Omega peptidase activity refers to the catalytic hydrolysis of peptide bonds at the C-terminal end of a protein or peptide. This activity is characteristic of a specific class of peptidases that cleave peptide chains specifically at the omega (ω) position, which is the last amino acid residue on the C-terminus. Omega peptidases are distinct from other peptidases based on their substrate specificity and catalytic mechanism. They play a crucial role in various cellular processes, including protein degradation, signal transduction, and the regulation of protein function.

Omega peptidases often exhibit a preference for specific amino acid residues at the P1 position, which is the amino acid residue immediately adjacent to the cleavage site. For example, some omega peptidases prefer to cleave after basic residues like arginine or lysine, while others prefer to cleave after hydrophobic residues like leucine or valine. The catalytic mechanism of omega peptidases typically involves the formation of a covalent intermediate between the enzyme and the substrate, followed by hydrolysis of the intermediate to release the cleaved product.

The specific molecular function of omega peptidase activity is dependent on the context in which it occurs. In some cases, omega peptidases may act as proteolytic enzymes, breaking down proteins into smaller peptides. In other cases, they may act as signal peptidases, removing signal sequences from newly synthesized proteins. Omega peptidases can also play a role in regulating the activity of other proteins by cleaving off specific domains or by processing precursor proteins into their active forms.

Overall, omega peptidase activity is an essential process in many cellular functions, and understanding its specific molecular mechanisms is crucial for comprehending a wide range of biological processes.'
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Proteins (1)

Compounds (7)