Encyclopedia of Biophysics

2013 Edition
| Editors: Gordon C. K. Roberts

Spin-Labeling EPR of Proteins: Dynamics and Water Accessibility of Spin-Label Side Chains

  • Enrica BordignonEmail author
Reference work entry
DOI: https://doi.org/10.1007/978-3-642-16712-6_584



By introducing a side chain carrying a paramagnetic center (spin label,  chemistry of spin labeling) at a desired site in a protein, one can obtain via EPR information on the dynamics of the side chain, its water accessibility, and the polarity of its microenvironment. Scanning those properties along the polypeptide chain can reveal details of the secondary and tertiary structure of the protein under investigation.


The subject of this entry is the application of site-directed spin labeling (SDSL) electron paramagnetic resonance (EPR) to characterize dynamics and water accessibility of specific sites in proteins. Some practical advantages of the use of EPR to study dynamics and water profiles in proteins should be emphasized. First of all the nitroxide label is relatively small and highly flexible, which enables its introduction at specific sites in proteins with minor perturbation of the protein structure. Second, SDSL EPR...

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Copyright information

© European Biophysical Societies' Association (EBSA) 2013

Authors and Affiliations

  1. 1.Laboratory of Physical ChemistryETHZurichSwitzerland