Issue 32, 2012

Binding motifs of silver in prion octarepeat model peptides: a joint ion mobility, IR and UV spectroscopies, and theoretical approach

Abstract

Transition metal-ion complexation is essential to the function and structural stability of many proteins. We studied silver complexation with the octarepeat motif ProHisGlyGlyGlyTrpGlyGln of the prion protein, which shows competitive sites for metal chelation including amide, indole and imidazole groups. This octapeptide is known as a favourable transition metal binding site in prion protein. We used ion mobility spectrometry (IMS), infrared multiple photon dissociation (IRMPD) spectroscopy and density functional theory calculations (DFT) to identify the binding motifs of a silver cation on HisGlyGlyGlyTrp peptide as well as on peptide subsequences. Ultra-violet photodissociation (UVPD) and collision induced dissociation mass spectrometry together with the time-dependent density functional method was then exploited to study the influence of binding sites on optical properties and on the ground and excited states reactivity of the peptide. We show that the metal cation is bound to the π-system of the indole group and a nitrogen atom of the imidazole group and that charge transfers from the indole group to the silver cation occur in excited electronic states.

Graphical abstract: Binding motifs of silver in prion octarepeat model peptides: a joint ion mobility, IR and UV spectroscopies, and theoretical approach

Supplementary files

Article information

Article type
Paper
Submitted
23 Mar 2012
Accepted
31 May 2012
First published
01 Jun 2012

Phys. Chem. Chem. Phys., 2012,14, 11433-11440

Binding motifs of silver in prion octarepeat model peptides: a joint ion mobility, IR and UV spectroscopies, and theoretical approach

B. Bellina, I. Compagnon, L. MacAleese, F. Chirot, J. Lemoine, P. Maître, M. Broyer, R. Antoine, A. Kulesza, R. Mitrić, V. Bonačić-Koutecký and P. Dugourd, Phys. Chem. Chem. Phys., 2012, 14, 11433 DOI: 10.1039/C2CP40924K

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements