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Long-range distance determinations in biomacromolecules by EPR spectroscopy

Published online by Cambridge University Press:  13 June 2007

Olav Schiemann  and
Thomas F. Prisner
Olav Schiemann*
Affiliation:
Institute of Physical and Theoretical Chemistry, Center for Biomolecular Magnetic Resonance, J. W. Goethe-University Frankfurt, 60438 Frankfurt am Main, Germany
Thomas F. Prisner*
Affiliation:
Institute of Physical and Theoretical Chemistry, Center for Biomolecular Magnetic Resonance, J. W. Goethe-University Frankfurt, 60438 Frankfurt am Main, Germany
*
*Correspondence may be addressed to either author at: Institute of Physical and Theoretical Chemistry, Center for Biomolecular Magnetic Resonance, J. W. Goethe-University, Max-von-Laue-Str. 7, 60438 Frankfurt am Main, Germany. Tel.: +49 (0) 69 798 29 786; Fax: +49 (0) 69 798 29 404. E-mail: O. Schiemann (o.schiemann@epr.uni-frankfurt.de); T. F. Prisner (prisner@chemie.uni-frankfurt.de)
*Correspondence may be addressed to either author at: Institute of Physical and Theoretical Chemistry, Center for Biomolecular Magnetic Resonance, J. W. Goethe-University, Max-von-Laue-Str. 7, 60438 Frankfurt am Main, Germany. Tel.: +49 (0) 69 798 29 786; Fax: +49 (0) 69 798 29 404. E-mail: O. Schiemann (o.schiemann@epr.uni-frankfurt.de); T. F. Prisner (prisner@chemie.uni-frankfurt.de)
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Abstract

Electron paramagnetic resonance (EPR) spectroscopy provides a variety of tools to study structures and structural changes of large biomolecules or complexes thereof. In order to unravel secondary structure elements, domain arrangements or complex formation, continuous wave and pulsed EPR methods capable of measuring the magnetic dipole coupling between two unpaired electrons can be used to obtain long-range distance constraints on the nanometer scale. Such methods yield reliably and precisely distances of up to 80 Å, can be applied to biomolecules in aqueous buffer solutions or membranes, and are not size limited. They can be applied either at cryogenic or physiological temperatures and down to amounts of a few nanomoles. Spin centers may be metal ions, metal clusters, cofactor radicals, amino acid radicals, or spin labels. In this review, we discuss the advantages and limitations of the different EPR spectroscopic methods, briefly describe their theoretical background, and summarize important biological applications. The main focus of this article will be on pulsed EPR methods like pulsed electron–electron double resonance (PELDOR) and their applications to spin-labeled biosystems.

Type
Review Article
Information
Quarterly Reviews of Biophysics , Volume 40 , Issue 1 , February 2007 , pp. 1 - 53
Copyright
Copyright © Cambridge University Press 2007

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