Peptides - compounds consisting of two (dipeptides), three (tripeptides) and more (polypeptides) residues of amino acids linked by peptide bonds .
Peptides are formed during incomplete acid (in the body - enzymatic) hydrolysis (see) proteins, as well as synthetically. Many biologically active substances, including certain hormones (see) and antibiotics (see)are peptides. Cm. Amino acids, Proteins.

The peptide, organic compound composed of amino acid residues related peptide (-NH-WITH-) connection. Peptides can consist of two, three, four and more of amino acid residues, and they are called, respectively, di-, tri-, Tetra -, and polypeptides. The molecule of Peterhof is an open chain amino and carboxyl groups at the ends. Meet P. closed loop - cyclopeptide; in this case they do not have free alpha-amino and alpha-carboxylic groups. on can be synthesized from amino acids or are formed in enzymatic cleavage of proteins. Among the natural p., there are some who possess biological activity; these include certain hormones (secretin, glucagon, adrenocorticotropic hormone, oxytocin, vasopressin), vitamins (Pantothenic acid, folic acid), antibiotics (gramicidines, tyrocidine). Most of peptide antibiotics is cyclopeptide, which include amino acids, usually not found in proteins.