Dipartimento di Chimica, Univ. di Napoli Federico II, Complesso Univ. Monte S. Angelo, Via Cintia, 80126 Napoli, Italy
Dipartimento di Scienze Chimiche, Università di Padova, Via Marzolo 1, 35131 Padova, Italy
Istituto Biostrutture E Bioimmagini, CNR, Via mezzocannone 16, 80134 Napoli, Italy
References: Not available.
Understanding Electron Transfer across Negatively-Charged Aib Oligopeptides
The physicochemical effects modulating the conformational behavior and the rate of intramolecular dissociative electron transfer in phthalimide-Aib n-peroxide peptides (n = 0-3) have been studied by an integrated density functional/continuum solvent model. We found that three different orientations of the phthalimide ring are possible, labeled φhel, φC7, and φpII. In the condensed phase, they are very close in energy when the system is neutral and short. When the peptide chain length increases and the system is negatively charged, Ohei becomes instead the most stable conformer. Our calculations confirm that the 3 10-helix is the most stable secondary structure for the peptide bridge. However, upon charge injection in the phthalimide end of the phthalimide-Aib3-peroxide, the peptide bridge can adopt an α-helix conformation as well. The study of the dependence of the frontier orbitals on the length and on the conformation of the peptide bridge (in agreement with experimental indications) suggests that for n = 3 the process could be influenced by a 310 → α-helix conformational transition of the peptide chain.
Understanding Electron Transfer across Negatively-Charged Aib Oligopeptides
Kállay C, Dávid A, Timári S, Nagy EM, Sanna D, Garribba E, Micera G, De Bona P, Pappalardo G, Rizzarelli E, Sóvágó I * Copper(II) complexes of rat amylin fragments(517 views) Dalton T (ISSN: 1477-9234, 1477-9226, 1477-9234electronic), 2011 Oct 14; 40(38): 9711-9721. Impact Factor:3.838 ViewExport to BibTeXExport to EndNote