proteolízise

Proteolysis is the breakdown of proteins into smaller polypeptides or amino acids. This process is a fundamental aspect of biochemistry and is carried out by a class of enzymes called proteases, also known as peptidases. Proteases catalyze the hydrolysis of peptide bonds, the bonds that link amino acids together in a protein chain.

Proteolysis occurs in virtually all living organisms and plays a crucial role in a wide range of biological processes. In digestion, proteases in the stomach and small intestine break down dietary proteins into amino acids, which are then absorbed by the body. Within cells, proteolysis is essential for protein turnover, the regulated degradation of proteins that allows for the removal of damaged or unneeded proteins and the recycling of their amino acids. This process is vital for cellular homeostasis and adaptation.

The selective degradation of specific proteins by proteolysis is tightly regulated and often mediated by the ubiquitin-proteasome system in eukaryotic cells. This system tags target proteins with ubiquitin molecules, marking them for destruction by the proteasome, a large protein complex that functions as a cellular garbage disposal. Beyond these general roles, proteolysis is also involved in more specialized functions such as blood clotting, immune system activation, cell signaling, and programmed cell death (apoptosis). Dysregulation of proteolysis has been implicated in various diseases, including cancer, neurodegenerative disorders, and inflammatory conditions.