The University of Southampton
University of Southampton Institutional Repository

Correlation of empirical magnetic susceptibility tensors and structure in low-spin haem proteins

Turner, D. L., Brennan, L., Messias, A. C., Teodoro, M. L. and Xavier, A. V. (2000) Correlation of empirical magnetic susceptibility tensors and structure in low-spin haem proteins European Biophysics Journal with Biophysics Letters, 29, (2), pp. 104-112. (doi:10.1007/s002490050255).

Record type: Article

Abstract

Experimental magnetic susceptibility tensors are reported for eight haems c with bis-His coordination. These data, obtained by fitting the dipolar shifts of backbone protons in the tetrahaem cytochromes c(3) from Desulfovibrio vulgaris and D. gigas, are analysed together with published values for other haem proteins. The x and y axes are found to rotate in the opposite sense to the axial ligands and are also counter-rotated with respect to the frontier molecular orbitals of the haem. The magnetic z-axis is close to the normal to the haem plane in each case. The magnitudes of the magnetic anisotropies are used to derive crystal field parameters and the rhombic splitting, V, is correlated with the dihedral angle between the axial ligands. Hence, it is apparent that the axial ligands are the dominant factor in determining the variation in magnetic properties between haems, and it is confirmed that "high g(max)'' EPR signals are a reliable indicator of near-perpendicular ligands. These results are in full agreement with the analysis of non-Curie effects and electronic structure in the His-Met coordinated cytochromes c and C-551. Collectively, they show that the orientations of axial ligands to the haem may be estimated from single-crystal EPR data, from C-13 NMR shifts of the haem substituents, or from NMR dipolar shifts of the polypeptide.

Full text not available from this repository.

More information

Published date: 2000
Keywords: heme electronic-structure, desulfovibrio-vulgaris hildenborough, paramagnetic nmr shifts, horse cytochrome-c, biological macromolecules, metmyoglobin cyanide, ferricytochrome-c, cross-relaxation, resonanceshifts, contact shifts

Identifiers

Local EPrints ID: 19049
URI: http://eprints.soton.ac.uk/id/eprint/19049
PURE UUID: e7f0d53b-ac1f-45d2-8f4c-e51faedbec1c

Catalogue record

Date deposited: 18 Jan 2006
Last modified: 17 Jul 2017 16:34

Export record

Altmetrics

Contributors

Author: D. L. Turner
Author: L. Brennan
Author: A. C. Messias
Author: M. L. Teodoro
Author: A. V. Xavier

University divisions

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×