tailieunhanh - Báo cáo Y học: Characterization of heparin binding by a peptide from amyloid P component using capillary electrophoresis, surface plasmon resonance and isothermal titration calorimetry

Division of Medicinal and Natural Products Chemistry, Department of Chemistry and Department of Chemical Engineering, University of Iowa, USA; 2Department of Autoimmunology, Statens Serum Institut, Copenhagen, Denmark Synthetic peptides based on amino-acid residues 27–38 of human serum amyloid P component represent a novel type of heparin binders as they do not contain clusters of basic amino acids or other known features associated with protein or peptide heparin binding. | Eur. J. Biochem. 269 2860-2867 2002 FEBS 2002 doi Characterization of heparin binding by a peptide from amyloid P component using capillary electrophoresis surface plasmon resonance and isothermal titration calorimetry Maria J. Hernaiz1 Laurie A. LeBrun1 Yi Wu1 Jette W. Sen2 Robert J. Linhardt1 and Niels H. H. Heegaard2 1 Division of Medicinal and Natural Products Chemistry Department of Chemistry and Department of Chemical Engineering University of Iowa USA department of Autoimmunology Statens Serum Institut Copenhagen Denmark Synthetic peptides based on amino-acid residues 27-38 of human serum amyloid P component represent a novel type of heparin binders as they do not contain clusters of basic amino acids or other known features associated with protein or peptide heparin binding. Here we characterize the hinding using capillary electrophoresis CE surface plasmon resonance SPR and isothermal titration calorimetry ITC . By CE. heparin-binding activity was readily apparent for both a regular peptide and a slightly N-terminally modified form while a sequence-scrambled peptide had no measurable binding. Dissociaiion conttants id the 1-15 M range were estimated but only a minor part of the binding isotherm was covered by the experiments. SPR measurements using immobiliied peptides verified heparin binding the range of the binding constants and the reduced binding of the sequence-scrambled peptide. SSrucSuratly denned heparin oligosaccharides were used to establish that while the tetrasaccharide is too small to exhibit strong binding little difference in binding strength is observed between hexa- and tetradeca-saccharides. Thare xxperimnnts also confirmed the almost complete lack of activity of the sequence-scrambled amino-acid sequencedependent binding and the importance of a disulfide bond in the peptide were verified by ITC but the experimental conditions had to be modified because of peptide precipitation and ITC yielded