title: Al(III)-binding ability of an octapeptide and its phosphorylated derivative.
abstract: A synthetic octapeptide, H-GlyGluGlyGluGlySerGlyGly-OH, and its phosphorylated Ser derivative were synthetized and their solution speciation and binding modes in their complexes with Al(III) were measured. One goal of the work was find a lead compound for the design of a selective peptide-based Al(III) chelator. pH-potentiometry was used to characterize the stoichiometry and the stability of the species formed in the interactions of the metal ion and the peptides, while multinuclear NMR was applied to characterize the binding sites of the metal ion in the complexes. CD spectroscopy revealed a difference in the conformational behaviour of the phosphorylated peptide as compared with its non-phosphorylated parent derivative. The Al(III) is presumed to enhance aggregation through the -PO3H(-)-Al(3+)-PO3(2-)-Al(3+)- intermolecular bindings between the peptide chains. The results of molecular dynamics calculations supported the experimentally obtained secondary structures and the binding position of Al(III).
authors.affiliation: MTA-SZTE Bioinorganic Chemistry Research Group, University of Szeged, PO Box 440, Szeged H-6701, Hungary.
authors.forename: Dominik
authors.initials: D
authors.lastname: Hollender
authors.forename: Andrea
authors.initials: A
authors.lastname: Károly-Lakatos
authors.forename: Péter
authors.initials: P
authors.lastname: Forgó
authors.forename: Tamás
authors.initials: T
authors.lastname: Körtvélyesi
authors.forename: György
authors.initials: G
authors.lastname: Dombi
authors.forename: Zsuzsa
authors.initials: Z
authors.lastname: Majer
authors.forename: Miklós
authors.initials: M
authors.lastname: Hollósi
authors.forename: Tamás
authors.initials: T
authors.lastname: Kiss
authors.forename: Akira
authors.initials: A
authors.lastname: Odani
mesh_terms: D000535:Aluminum / Q000737:chemistry* / Q000378:metabolism; D002614:Chelating Agents / Q000737:chemistry / Q000378:metabolism; D002942:Circular Dichroism; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D008968:Molecular Conformation; D009842:Oligopeptides / Q000737:chemistry* / Q000378:metabolism; D010766:Phosphorylation; D011199:Potentiometry; D011485:Protein Binding; D011522:Protons; D012694:Serine / Q000737:chemistry
chemical_list: D002614:Chelating Agents; D009842:Oligopeptides; D011522:Protons; D012694:Serine; D000535:Aluminum