Tetrapeptide

A tetrapeptide is a peptide, classified as an oligopeptide, since it only consists of four amino acids joined by peptide bonds. Many tetrapeptides are pharmacologically active, often showing affinity and specificity for a variety of receptors in protein-protein signaling. Present in nature are both linear and cyclic tetrapeptides, tetrapeptides may be cyclized by a fourth peptide bond or other covalent bonds.

Examples of tetrapeptides are:

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