Identification of two related pentapeptides from the brain with potent opiate agonist activity

• DOI: 10.1038/258577a0
• Publication Date: 2005-08-03T17:43:54Z
• Authors: J. Hughes; T. W. Smith; H. W. Kosterlitz; Linda A. Fothergill; B. A. Morgan; H. R. Morris
• Keywords: Opiate; Edman degradation

Enkephalin, a natural ligand for opiate receptors is composed of the pentapepides H-Tyr-Gly-Gly-Phe-Met-OH and H-Tyr-Gly-Gly-Phe-Leu-OH. The evidence is based on the determination of the amino acid sequence of natural enkephalin by the dansyl-Edman procedure and by mass spectrometry followed by synthesis and comparison of the natural and synthetic peptides.