Site-directed spin labeling EPR spectroscopy in protein research

• Published in: Biological chemistry Vol. 394; no. 10; pp. 1281 - 1300
• Main Author: Klare, Johann P.
• Format: Journal Article
• Language: English
• Published: Germany De Gruyter 01.10.2013
• Subjects: conformational dynamics; electron paramagnetic resonance (EPR) spectroscopy; Electron Spin Resonance Spectroscopy; Membrane Proteins - chemistry; protein function; protein structure; Protein Structure, Secondary; protein-nucleic acid interaction; protein-protein interaction; Proteins - chemistry; site-directed spin labeling (SDSL); Spin Labels
• ISSN: 1431-6730; 1437-4315
• DOI: 10.1515/hsz-2013-0155

Site-directed spin labeling (SDSL) in combination with electron paramagnetic resonance (EPR) spectroscopy has emerged as an efficient tool to elucidate the structure and the conformational dynamics of proteins under conditions close to the native state. This review article summarizes the basics as well as the recent progress in SDSL and EPR methods, especially for investigations on protein structure, protein function, and interaction of proteins with other proteins or nucleic acids. Labeling techniques as well as EPR methods are introduced and exemplified with applications to systems that have been studied in the author’s laboratory in the past 15 years, headmost the sensory rhodopsin-transducer complex mediating the photophobic response of the halophilic archaeum . Further examples underline the application of SDSL EPR spectroscopy to answer specific questions about the system under investigation, such as the nature and influence of interactions of proteins with other proteins or nucleic acids. Finally, it is discussed how SDSL EPR can be combined with other biophysical techniques to combine the strengths of the different methodologies.