title: The dimeric and tetrameric octarepeat fragments of prion protein behave differently to its monomeric unit.
abstract: Potentiometric and spectroscopic data have shown that octarepeat dimer and tetramer are much more effective ligands for Cu(II) ions than simple octapeptide. Thus, the whole N-terminal segment of prion protein due to cooperative effects, could be more effective in binding of Cu(II) than simple peptides containing a His residue. The gain of the Cu(II) binding by longer octarepeat peptides derives from the involvement of up to four imidazoles in the coordination of the first Cu(II) ion. This type of binding increases the order of the peptide structure, which allows successive metal ions for easier coordination.
authors.affiliation: Department of Chemistry, University of Siena, via Aldo Moro, I-53100 Siena, Italy. valensin@unisi.it
authors.forename: Daniela
authors.initials: D
authors.lastname: Valensin
authors.forename: Marek
authors.initials: M
authors.lastname: Luczkowski
authors.forename: Francesca Maria
authors.initials: FM
authors.lastname: Mancini
authors.forename: Anna
authors.initials: A
authors.lastname: Legowska
authors.forename: Elena
authors.initials: E
authors.lastname: Gaggelli
authors.forename: Gianni
authors.initials: G
authors.lastname: Valensin
authors.forename: Krzysztof
authors.initials: K
authors.lastname: Rolka
authors.forename: Henryk
authors.initials: H
authors.lastname: Kozlowski
mesh_terms: D001665:Binding Sites; D002413:Cations, Divalent; D003300:Copper / Q000737:chemistry*; D004578:Electron Spin Resonance Spectroscopy; D008024:Ligands; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular; D010446:Peptide Fragments / Q000737:chemistry*; D011328:Prions / Q000737:chemistry*; D011487:Protein Conformation; D020449:Repetitive Sequences, Amino Acid
chemical_list: D002413:Cations, Divalent; D008024:Ligands; D010446:Peptide Fragments; D011328:Prions; D003300:Copper