title: Intermolecular disulfide bonds link specific high-molecular-weight glutenin subunits in wheat endosperm.
abstract: A detergent wash extracted soluble proteins from wheat flour, leaving a residue enriched with insoluble glutenin aggregates. Digestion of this residue with endoproteinase Lys-C, which showed a limited specificity for glutenin subunits, produced several peptides with apparent molecular weights close to those of intact high-molecular-weight glutenin subunits. N-terminal sequencing indicated that the isolated peptides were composed of high-molecular-weight glutenin subunit fragments joined by an intermolecular disulfide bond. In two of these peptides, only two components were found, one from an x-type subunit and the other from a y-type subunit. The isolated peptides all contained at least one x-type C-terminal region and one y-type N-terminal region, suggesting a specific orientation to the intermolecular disulfide linkage.
authors.affiliation: Western Regional Research Center, U.S. Department of Agriculture, Albany, CA 94710.
authors.forename: H P
authors.initials: HP
authors.lastname: Tao
authors.forename: A E
authors.initials: AE
authors.lastname: Adalsteins
authors.forename: D D
authors.initials: DD
authors.lastname: Kasarda
mesh_terms: D000595:Amino Acid Sequence; D004220:Disulfides / Q000737:chemistry; D005983:Glutens / Q000031:analogs & derivatives* / Q000737:chemistry; D008666:Metalloendopeptidases / Q000494:pharmacology; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010446:Peptide Fragments / Q000737:chemistry; D014908:Triticum / Q000737:chemistry
chemical_list: D004220:Disulfides; D010446:Peptide Fragments; D005983:Glutens; D008666:Metalloendopeptidases; C039830:peptidyl-Lys metalloendopeptidase; C037302:glutenin