peptide bond

Bond that joins two amino acids together within a protein. The carboxyl (COOH) group on one amino acid reacts with the amino (NH2) group on another amino acid to form a peptide bond (CONH) with the elimination of water.

In a cell, nearly all peptide bonds are produced by the ribosome, which transfers the growing polypeptide chain to the aminoacyl-tRNA, using the peptidyl transferase activity. Only a small number of small peptides are produced by other enzymes.

Peptide bonds are broken by hydrolytic enzymes called peptidases and proteases.