title: Copper(II) binding to Cap43 protein fragments.
abstract: The C-terminal 20 and 30 amino acid sequences of Cap43 protein were chosen as models to study their interactions with Cu(II) ions. The behaviour of the 20 amino acid Ac-TRSRSH6TSEG-TRSRSH16TSEG and 30 amino acid Ac-TRSRSH6TSEG-TRSRSH16TSEG-TRSRSH26TSEG peptides towards Cu(II) ions at different pH values and different ligand-to-metal molar ratios, was examined. Spectroscopic (EPR, UV-Vis) and potentiometric techniques were performed to understand the details of metal binding to the peptides. The study showed that, starting from pH 4.0, each 10 amino acid fragment T1R2S3R4S5H6T7S8E9G10 was able to independently coordinate a single Cu(II) ion. The coordination mode involved the imidazole nitrogen of histidine H6 residue, and three amidic nitrogens from histidine H6, serine S5, and arginine R4 residues, respectively.
authors.affiliation: Department of Chemistry, University of Sassari, Italy. zoroddu@uniss.it
authors.forename: Maria Antonietta
authors.initials: MA
authors.lastname: Zoroddu
authors.forename: Teresa
authors.initials: T
authors.lastname: Kowalik-Jankowska
authors.forename: Serenella
authors.initials: S
authors.lastname: Medici
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Peana
authors.forename: Henryk
authors.initials: H
authors.lastname: Kozlowski
mesh_terms: D002413:Cations, Divalent / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000378:metabolism*; D003300:Copper / Q000378:metabolism*; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D010446:Peptide Fragments / Q000138:chemical synthesis / Q000737:chemistry / Q000378:metabolism*; D000099259:N-myc Downstream-Regulated Gene 1 Protein
chemical_list: D002413:Cations, Divalent; D018797:Cell Cycle Proteins; D003300:Copper; D047908:Intracellular Signaling Peptides and Proteins; D010446:Peptide Fragments; D000099259:N-myc Downstream-Regulated Gene 1 Protein