title: Peptide-Membrane Interactions by Spin-Labeling EPR.
abstract: Site-directed spin labeling (SDSL) in combination with electron paramagnetic resonance (EPR) spectroscopy is a well-established method that has recently grown in popularity as an experimental technique, with multiple applications in protein and peptide science. The growth is driven by development of labeling strategies, as well as by considerable technical advances in the field, that are paralleled by an increased availability of EPR instrumentation. While the method requires an introduction of a paramagnetic probe at a well-defined position in a peptide sequence, it has been shown to be minimally destructive to the peptide structure and energetics of the peptide-membrane interactions. In this chapter, we describe basic approaches for using SDSL EPR spectroscopy to study interactions between small peptides and biological membranes or membrane mimetic systems. We focus on experimental approaches to quantify peptide-membrane binding, topology of bound peptides, and characterize peptide aggregation. Sample preparation protocols including spin-labeling methods and preparation of membrane mimetic systems are also described.
authors.affiliation: Department of Chemistry, North Carolina State University, Raleigh, North Carolina, USA. Electronic address: tismirno@ncsu.edu.
authors.forename: Tatyana I
authors.initials: TI
authors.lastname: Smirnova
authors.affiliation: Department of Chemistry, North Carolina State University, Raleigh, North Carolina, USA.
authors.forename: Alex I
authors.initials: AI
authors.lastname: Smirnov
mesh_terms: D000818:Animals; D001665:Binding Sites; D002462:Cell Membrane / Q000737:chemistry / Q000378:metabolism*; D004578:Electron Spin Resonance Spectroscopy / Q000379:methods*; D006801:Humans; D008051:Lipid Bilayers / Q000737:chemistry / Q000378:metabolism*; D010455:Peptides / Q000737:chemistry / Q000378:metabolism*; D066329:Protein Aggregates; D013113:Spin Labels; D013816:Thermodynamics
chemical_list: D008051:Lipid Bilayers; D010455:Peptides; D066329:Protein Aggregates; D013113:Spin Labels
keywords: Accessibility EPR experiments; Binding isotherms; Membrane mimetics; Peptide aggregation; Peptide binding