title: Inter- and intra-molecular distances determined by EPR spectroscopy and site-directed spin labeling reveal protein-protein and protein-oligonucleotide interaction.
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.
authors.affiliation: Fachbereich Physik, Universität Osnabrück, D-49069 Osnabrück, Germany. hsteinho@uos.de
authors.forename: Heinz-Jürgen
authors.initials: HJ
authors.lastname: Steinhoff
mesh_terms: D000818:Animals; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods*; D006801:Humans; D009841:Oligonucleotides / Q000737:chemistry / Q000378:metabolism*; D011485:Protein Binding / Q000502:physiology; D025941:Protein Interaction Mapping / Q000379:methods*; D013113:Spin Labels
chemical_list: D009841:Oligonucleotides; D013113:Spin Labels