title: Saturation Recovery EPR and Nitroxide Spin Labeling for Exploring Structure and Dynamics in Proteins.
abstract: Experimental techniques capable of determining the structure and dynamics of proteins are continuously being developed in order to understand protein function. Among existing methods, site-directed spin labeling in combination with saturation recovery (SR) electron paramagnetic resonance spectroscopy contributes uniquely to the determination of secondary and tertiary protein structure under physiological conditions, independent of molecular weight and complexity. In addition, SR of spin labeled proteins was recently demonstrated to be sensitive to conformational exchange events with characteristic lifetimes on the order of μs, a time domain that presents a significant challenge to other spectroscopic techniques. In this chapter, we present the theoretical background necessary to understand the capabilities of SR as applied to spin labeled proteins, the instrumental requirements, and practical experimental considerations necessary to obtain interpretable data, and the use of SR to obtain information on protein: (1) secondary structure via solvent accessibility measurements, (2) tertiary structure using interspin distance measurements, and (3) conformational exchange.
authors.affiliation: Jules Stein Eye Institute and Department of Chemistry and Biochemistry, University of California, Los Angeles, California, USA.
authors.forename: Zhongyu
authors.initials: Z
authors.lastname: Yang
authors.affiliation: Jules Stein Eye Institute and Department of Chemistry and Biochemistry, University of California, Los Angeles, California, USA.
authors.forename: Michael
authors.initials: M
authors.lastname: Bridges
authors.affiliation: Jules Stein Eye Institute and Department of Chemistry and Biochemistry, University of California, Los Angeles, California, USA.
authors.forename: Michael T
authors.initials: MT
authors.lastname: Lerch
authors.affiliation: Jules Stein Eye Institute and Department of Chemistry and Biochemistry, University of California, Los Angeles, California, USA.
authors.forename: Christian
authors.initials: C
authors.lastname: Altenbach
authors.affiliation: Jules Stein Eye Institute and Department of Chemistry and Biochemistry, University of California, Los Angeles, California, USA. Electronic address: hubbellw@jsei.ucla.edu.
authors.forename: Wayne L
authors.initials: WL
authors.lastname: Hubbell
mesh_terms: D000465:Algorithms; D000818:Animals; D004578:Electron Spin Resonance Spectroscopy / Q000295:instrumentation / Q000379:methods*; D006801:Humans; D008958:Models, Molecular; D011487:Protein Conformation; D011506:Proteins / Q000737:chemistry*; D013113:Spin Labels
chemical_list: D011506:Proteins; D013113:Spin Labels
keywords: Conformational exchange; EPR; Protein structure; Saturation recovery; Spin labeling