carboxypeptidázy

Carboxypeptidases are a group of enzymes that catalyze the hydrolysis of peptide bonds, releasing a single amino acid residue from the carboxyl terminus of a polypeptide chain. They are essential for protein metabolism and play crucial roles in various physiological processes. These enzymes are classified as proteases or peptidases, specifically exopeptidases, meaning they act on the terminal amino acids of a protein.

Carboxypeptidases are broadly divided into two main classes: carboxypeptidase A and carboxypeptidase B. Carboxypeptidase A preferentially cleaves amino acids with aromatic or bulky aliphatic side chains, such as phenylalanine, tyrosine, tryptophan, and leucine. Carboxypeptidase B, on the other hand, is more specific for basic amino acids like arginine and lysine. This specificity allows them to precisely break down proteins into their constituent amino acids or smaller peptides.

These enzymes are found in various organisms, including humans, where they are involved in digestive processes in the pancreas and in protein turnover within cells. They are also secreted by bacteria and plants for nutrient acquisition. The activity of carboxypeptidases is often regulated by cofactors and inhibitors, ensuring precise control over protein degradation. Understanding their function is vital for comprehending protein homeostasis and for developing therapeutic strategies targeting protein-related diseases.