Faculty Collaboration Database

Spin hamiltonian parameters for Cu(II)-prion peptide complexes from L-band electron paramagnetic resonance spectroscopy. J Am Chem Soc 2011 Feb 16;133(6):1814-23

Date

01/27/2011

Pubmed ID

21265507

Pubmed Central ID

PMC3150385

DOI

10.1021/ja106550u

Scopus ID

2-s2.0-79951544551 (requires institutional sign-in at Scopus site)   12 Citations

Abstract

Cu(II) is an essential element for life but is also associated with numerous and serious medical conditions, particularly neurodegeneration. Structural modeling of crystallization-resistant biological Cu(II) species relies on detailed spectroscopic analysis. Electron paramagnetic resonance (EPR) can, in principle, provide spin hamiltonian parameters that contain information on the geometry and ligand atom complement of Cu(II). Unfortunately, EPR spectra of Cu(II) recorded at the traditional X-band frequency are complicated by (i) strains in the region of the spectrum corresponding to the g(∥) orientation and (ii) potentially very many overlapping transitions in the g(⊥) region. The rapid progress of density functional theory computation as a means to correlate EPR and structure, and the increasing need to study Cu(II) associated with biomolecules in more biologically and biomedically relevant environments such as cells and tissue, have spurred the development of a technique for the extraction of a more complete set of spin hamiltonian parameters that is relatively straightforward and widely applicable. EPR at L-band (1-2 GHz) provides much enhanced spectral resolution and straightforward analysis via computer simulation methods. Herein, the anisotropic spin hamiltonian parameters and the nitrogen coordination numbers for two hitherto incompletely characterized Cu(II)-bound species of a prion peptide complex are determined by analysis of their L-band EPR spectra.

Author List

Kowalski JM, Bennett B

Author

Brian Bennett D.Phil. Professor and Chair in the Physics department at Marquette University

MESH terms used to index this publication - Major topics in bold

Anisotropy
Copper
Electron Spin Resonance Spectroscopy
Organometallic Compounds
Peptide Fragments
Prions
Quantum Theory