title: Multidimensional NMR spectroscopy for the study of histone H4-Ni(II) interaction.
abstract: The N-terminal 30-amino acid tail of histone H4, a nuclear protein, was studied as a model for the interaction of this protein with Ni(ii) ions. The behaviour of the ends-blocked Ac-SGRGKGGKGLGKGGA(15)K(16)R(17)H(18)R(19)KVLRDNIQGIT-Am fragment towards Ni(ii) was analyzed with multidimensional NMR (1D, 2D TOCSY, NOESY) and UV-Vis spectroscopy. As expected, the coordination involved the imidazolic nitrogen of the His(18) residue and the three deprotonated amidic nitrogens of the His(18), Arg(17) and Lys(16) residues, respectively. A model for the structure of the complex was calculated from the inter-residual NOEs recorded in 2D NOESY spectra. The structure obtained shows that the interaction with the metal is responsible for deep changes in the conformation of the peptide, blocking the side chain of Arg(17) and Lys(16) residues above the coordination plane. These structural modifications may be physiologically relevant to the mechanism of nickel carcinogenesis.
authors.affiliation: Department of Chemistry, University of Sassari, via Vienna 2, 07100 Sassari, Italy. zoroddu@uniss.it
authors.forename: Maria Antonietta
authors.initials: MA
authors.lastname: Zoroddu
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Peana
authors.forename: Serenella
authors.initials: S
authors.lastname: Medici
mesh_terms: D000595:Amino Acid Sequence; D006657:Histones / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008969:Molecular Sequence Data; D009532:Nickel / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet
chemical_list: D006657:Histones; D009532:Nickel