Proteolysis
| Parent |
| Metabolism of proteins |
| Subordinate |
| Intracellular proteolysis Extracellular proteolysis Regulation of proteolysis |
| Gene Ontology |
|---|
| QuickGO |
As proteolysis (from the Greek lysis , "Resolution") refers to the enzymatic hydrolysis of proteins by peptidases , so the breakdown of proteins. From Autoproteolysis is when a peptidase degrades itself. Proteolysis can be inhibited by protease inhibitors . A protein hydrolyzate is a product of proteolysis.
properties
Proteolysis can be classified according to its localization:
- Intracellular proteolysis
- Breakdown of the cell's own proteins in the proteasome
- Breakdown of phagocytosed proteins in the lysosome
- Extracellular proteolysis
- Degradation of proteins of the extracellular matrix by secreted or membrane-bound proteases at the cellular level
- Breakdown of proteins ingested through food in the gastrointestinal tract via proteases synthesized in the stomach , duodenum or pancreas (for example pepsin , carboxypeptidases , aminopeptidases , trypsin , chymotrypsin , elastase , collagenase ).
In addition, the peptidases can also be subdivided according to their degradation mechanism. Exopeptidases break down proteins from the N- or C-terminus of the amino acid sequence , while endopeptidases break down a protein at a specific recognition sequence . Endopeptidases are further subdivided according to their active site .
Proteolysis has a decisive influence on the biological half-life of proteins. The peptides released during proteolysis can be reused for protein biosynthesis or used to generate energy in the course of biochemical degradation after being broken down into individual amino acids .
The organism also uses proteolysis to release peptides and proteins from preproteins such as B. to activate zymogens such as ADH and Neurophysin or for post-translational modification .
literature
- Friedrich Lottspeich , Haralabos Zorbas: Bioanalytics . Spektrum Akademischer Verlag, Heidelberg 1998, ISBN 978-3827400413 .
- Hubert Rehm , Thomas Letzel: The Experimenter: Protein Biochemistry / Proteomics . 6th edition, Spektrum Akademischer Verlag, Heidelberg 2009, ISBN 978-3827423122 .
- Donald Voet, Judith G. Voet: Biochemistry . 3. Edition. John Wiley & Sons Inc., London 2004, ISBN 0-471-39223-5 .