title: The structure of synenkephalin (pro-enkephalin 1-73) is dictated by three disulfide bridges.
abstract: Mass spectrometry of fragments produced by limited proteolytic digestion of pro-enkephalin was used to locate the disulfide bridges in synenkephalin (pro-enkephalin 1-73), a domain which contains sorting information for targeting the pro-neuropeptide to the granules of the regulated secretory pathway in neuroendocrine cells. Mass spectrometric analysis was optimized by using chemicals that gave low interference with the ionization and desorption processes, and computer software which simplified the identification of all possible disulfide-linked peptide fragments. Three disulfide bridges between Cys2-Cys24, Cys6-Cys28, and Cys9-Cys41 were identified. Protein conformational prediction of synenkephalin1-42 shows beta-turns which facilitate the formation of these disulfide bonds.
authors.affiliation: Laboratory of Bioorganic Chemistry, NIDDK, National Institutes of Health, Bethesda, Maryland 20892, USA.
authors.forename: P
authors.initials: P
authors.lastname: Lecchi
authors.forename: Y P
authors.initials: YP
authors.lastname: Loh
authors.forename: C R
authors.initials: CR
authors.lastname: Snell
authors.forename: L K
authors.initials: LK
authors.lastname: Pannell
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D016466:CHO Cells; D006224:Cricetinae; D003545:Cysteine / Q000737:chemistry; D004220:Disulfides / Q000737:chemistry; D004745:Enkephalins / Q000737:chemistry* / Q000235:genetics; D008969:Molecular Sequence Data; D015394:Molecular Structure; D010446:Peptide Fragments / Q000737:chemistry / Q000235:genetics; D011487:Protein Conformation; D011498:Protein Precursors / Q000737:chemistry* / Q000235:genetics; D017433:Protein Structure, Secondary; D051381:Rats; D011994:Recombinant Proteins / Q000737:chemistry / Q000235:genetics; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D014357:Trypsin
chemical_list: D004220:Disulfides; D004745:Enkephalins; D010446:Peptide Fragments; D011498:Protein Precursors; D011994:Recombinant Proteins; C036693:synenkephalin; D014357:Trypsin; D003545:Cysteine