title: Biochemistry of the enkephalins and enkephalin-containing peptides.
abstract: The enkephalins are present in many tissues not only as the free pentapeptides, but also as internal sequences in larger polypeptides of varying size. Fourteen enkephalin-containing peptides (EC peptides) from beef adrenal medulla were isolated and sequenced, and the presence of a protein that contained several [Met]enkephalin sequences and one of [Leu]enkephalin was demonstrated. Because the latter was assumed to represent the gene product, it was named proenkephalin. Sequence data from the EC peptides made possible the synthesis of a polynucleotide probe with essentially no degeneracy and permitted the cloning of a partial proenkephalin cDNA. The complete structure of proenkephalin was deduced from both peptide and cDNA sequencing data. Proenkephalin is now known to be one of three enkephalin-containing gene products, each of which gives rise to many physiologically active peptides.
mesh_terms: D000313:Adrenal Medulla / Q000378:metabolism; D000595:Amino Acid Sequence; D000818:Animals; D002417:Cattle; D055598:Chemical Phenomena; D002621:Chemistry; D004745:Enkephalins / Q000235:genetics / Q000302:isolation & purification*; D010455:Peptides / Q000302:isolation & purification*; D010908:Pituitary Hormones, Anterior / Q000302:isolation & purification; D011333:Pro-Opiomelanocortin; D014176:Protein Biosynthesis; D011498:Protein Precursors / Q000302:isolation & purification
chemical_list: D004745:Enkephalins; D010455:Peptides; D010908:Pituitary Hormones, Anterior; D011498:Protein Precursors; C029992:proenkephalin; D011333:Pro-Opiomelanocortin