title: Transition metal complexes of terminally protected peptides containing histidyl residues.
abstract: Histidine-containing peptide fragments of prion protein are efficient ligands to bind various transition metal ions and they have high selectivity in metal binding. The metal ion affinity follows the order: Pd(II)>>Cu(II)>>Ni(II)Zn(II)>Cd(II) approximately Co(II)>Mn(II). The high selectivity of metal binding is connected to the involvement of both imidazole and amide nitrogen atoms in metal binding for Pd(II), Cu(II) and Ni(II), while only the monodentate N(im)-coordination is possible with the other metal ions. The stoichiometry and binding mode of palladium(II) complexes show great variety depending on the metal ion to ligand ratio, pH and especially the presence of coordinating donor atoms in the side chains of peptide fragments. It is also clear from our data that the peptide fragments containing histidine outside the octarepeat (His96, His111 and His187) are more efficient ligands than the monomer peptide fragments of the octarepeat domain.
authors.affiliation: Department of Inorganic and Analytical Chemistry, University of Debrecen, P.O. Box 21, H-4010 Debrecen, Hungary.
authors.forename: Viktória
authors.initials: V
authors.lastname: Jószai
authors.forename: Zoltán
authors.initials: Z
authors.lastname: Nagy
authors.forename: Katalin
authors.initials: K
authors.lastname: Osz
authors.forename: Daniele
authors.initials: D
authors.lastname: Sanna
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Di Natale
authors.forename: Diego
authors.initials: D
authors.lastname: La Mendola
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Pappalardo
authors.forename: Enrico
authors.initials: E
authors.lastname: Rizzarelli
authors.forename: Imre
authors.initials: I
authors.lastname: Sóvágó
mesh_terms: D000818:Animals; D002645:Chickens; D006639:Histidine / Q000737:chemistry*; D006801:Humans; D009942:Organometallic Compounds / Q000737:chemistry* / Q000378:metabolism; D010455:Peptides / Q000737:chemistry* / Q000378:metabolism; D011328:Prions / Q000737:chemistry / Q000378:metabolism; D028561:Transition Elements / Q000737:chemistry* / Q000378:metabolism
chemical_list: D009942:Organometallic Compounds; D010455:Peptides; D011328:Prions; D028561:Transition Elements; D006639:Histidine