title: Elevated intrinsic reactivity of seryl hydroxyl groups within the linear peptide triads His-Xaa-Ser or Ser-Xaa-His.
abstract: Chemical modification studies of peptide hormones and random peptides have revealed that seryl hydroxyl groups had enhanced reactivity toward acylating reagents when they occurred in the linear triads His-Xaa-Ser or Ser-Xaa-His (Xaa = any amino acid). O-acylation of serine within these triads was achieved by reaction with N-hydroxysuccinimide esters of biotin (NHS-biotin) and succinic anhydride. Seryl residues not occurring in His-Xaa-Ser/Ser-Xaa-His triads showed no reactivity towards NHS-biotin under reaction conditions described. Results of histidine replacement studies and studies of the pH dependence of O-biotinylation indicated that the increased nucleophilicity of the seryl hydroxyl group was due to intramolecular interaction between the seryl and histidyl residues. Our findings provide strong evidence that such triads represent novel consensus motifs in peptides.
authors.affiliation: Department of Anatomy and Neurosciences, University of Texas Medical Branch, Galveston 77555.
authors.forename: B T
authors.initials: BT
authors.lastname: Miller
authors.forename: A
authors.initials: A
authors.lastname: Kurosky
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D000682:Amyloid / Q000737:chemistry; D001710:Biotin / Q000031:analogs & derivatives / Q000737:chemistry; D002116:Calcitonin / Q000737:chemistry; D016384:Consensus Sequence; D004600:Eledoisin / Q000031:analogs & derivatives / Q000737:chemistry; D007987:Gonadotropin-Releasing Hormone / Q000031:analogs & derivatives / Q000737:chemistry; D006728:Hormones / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D058228:Islet Amyloid Polypeptide; D008969:Molecular Sequence Data; D009496:Neurotensin / Q000737:chemistry; D010446:Peptide Fragments / Q000737:chemistry*; D010455:Peptides / Q000737:chemistry*; D017421:Sequence Analysis; D012694:Serine / Q000737:chemistry*; D013386:Succinates / Q000737:chemistry; D019802:Succinic Acid; D013388:Succinimides / Q000737:chemistry
chemical_list: D000596:Amino Acids; D000682:Amyloid; D006728:Hormones; D058228:Islet Amyloid Polypeptide; D010446:Peptide Fragments; D010455:Peptides; D013386:Succinates; D013388:Succinimides; D007987:Gonadotropin-Releasing Hormone; D009496:Neurotensin; D012694:Serine; D004600:Eledoisin; D001710:Biotin; C037553:katacalcin; D002116:Calcitonin; D019802:Succinic Acid; C001426:N-hydroxysuccinimide