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Updated: Aug 20, 2026

Site Directed Spin Labeling and EPR Spectroscopic Studies of Pentameric Ligand-Gated Ion Channels
Published on: July 4, 2016
Inter- and intra-molecular distances determined by EPR spectroscopy and site-directed spin labeling reveal
1Fachbereich Physik, Universität Osnabrück, D-49069 Osnabrück, Germany. hsteinho@uos.de
Abstract:
Recent developments including pulse and multi-frequency techniques make the combination of site-directed spin labeling and electron paramagnetic resonance (EPR) spectroscopy an attractive approach for the study of protein-protein or protein-oligonucleotide interaction. Analysis of the spin label side chain mobility, its solvent accessibility, the polarity of the spin label micro-environment and distances between spin label side chains allow the modeling of protein domains or protein-protein interaction sites and their conformational changes with a spatial resolution at the level of the backbone fold. Structural changes can be detected with millisecond time resolution. Inter- and intra-molecular distances are accessible in the range from approximately 0.5 to 8 nm by the combination of continuous wave and pulse EPR methods. Recent applications include the study of transmembrane substrate transport, membrane channel gating, gene regulation and signal transfer.
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