Living Reference Work Entry

Modern Magnetic Resonance

pp 1-13

Date: Latest Version

Solid-State NMR for Studying Peptide Structures and Peptide-Lipid Interactions in Membranes

  • Erik StrandbergAffiliated withInstitute of Biological Interfaces (IBG-2), Karlsruhe Institute of Technology (KIT) Email author 
  • , Anne S. UlrichAffiliated withInstitute of Biological Interfaces (IBG-2), Karlsruhe Institute of Technology (KIT)Institute of Organic Chemistry, KIT

Abstract

Peptide-lipid interactions can be conveniently studied using solid-state NMR (SSNMR), as various approaches have been developed to resolve the structures of membrane-bound peptides under quasi-native conditions. By labeling peptides with NMR-active nuclei, it is possible to characterize their conformation, orientation, and dynamics within a lipid bilayer and to obtain information about their self-assembly and aggregation behavior. This review is focused on peptides that are labeled with 2H or 15N and describe results primarily from two important classes of helical peptides: (i) hydrophobic transmembrane model peptides and (ii) amphipathic antimicrobial peptides. It can be concluded from these SSNMR studies that both types of peptides exhibit specific effects under conditions of hydrophobic mismatch, i.e., when the (hydrophobic) length of the peptide differs from the hydrophobic thickness of the bilayer. In particular, when the peptide is too long, it compensates this mismatch by tilting in the membrane, thereby providing an effective (hydrophobic) length to match the membrane thickness. It was also observed that peptides can more easily insert into membranes when the bilayer is composed of lipids with a large positive spontaneous curvature, such as lysolipids.

Keywords

Solid-state NMR 2H- and 15N-labeled peptides Alpha-helical membrane-bound peptides Transmembrane model peptides Amphipathic antimicrobial peptides Peptide orientation and dynamics Hydrophobic mismatch Lipid spontaneous curvature Geometric analysis of labeled alanine (GALA) method