NR AWWW
AU Marino,T.; Russo,N.; Toscano,M.
TI On the copper(II) ion coordination by prion protein HGGGW pentapeptide model
QU The Journal of Physical Chemistry. B 2007 Jan 25; 111(3): 635-40
PT journal article; research support, non-u.s. gov't
AB The interaction of the octapeptide domain of the prion protein with the transition-metal-ion Cu2+ was studied at the DFT level by using the HGGGW pentapeptide as a model to mimic the PHGGGWGQ octarepeat sequence. Ten complexes, in which the metal ion exhibits different coordinations, were considered. Our results indicate that the lowest-energy structure is characterized by a tetracoordinated metal center and that this tendency of the ion to assume the square planar geometry is strong enough to prevent the addition of a further water molecule in its coordination sphere. The role of tryptophan was found to cause a lowering of the system energy due to the stabilizing effect of the electrostatic interaction between the Trp aromatic indole and histidine imidazole rings.
MH Circular Dichroism; Copper/*chemistry; Crystallography, X-Ray; Humans; Magnetic Resonance Spectroscopy; Models, Chemical; Models, Molecular; Oligopeptides/*chemistry; Oxidation-Reduction; Prions/*chemistry; Spectrometry, Mass, Electrospray Ionization; Tryptophan/chemistry
AD Dipartimento di Chimica and Centro di Calcolo ad Alte Prestazioni per Elaborazioni Parallele e Distribuite-Centro d'Eccellenza MIUR, Universita della Calabria, I-87030 Arcavacata di Rende (CS), Italy.
SP englisch
PO USA