Probing membrane protein orientation and structure using fast magic-angle-spinning solid-state NMR

Abstract

One and two-dimensional solid-state NMR experiments are discussed that permit probing local structure and overall molecular conformation of membrane-embedded polypeptides under Magic Angle Spinning. The functional dependence of a series of anisotropic recoupling schemes is analyzed using theoretical and numerical methods. These studies lead to the construction of a set of polarization dephasing or transfer units that probe local backbone conformation and overall molecular orientation within the same NMR experiment. Experimental results are shown for a randomly oriented peptide and for two model membrane-peptides reconstituted into lipid bilayers and oriented on polymer films according to a method proposed by Bechinger et al.

On the Role of NMR Spectroscopy for Characterization of Antimicrobial Peptides

“…Meeting this need, solid-state NMR techniques are well suited for studying membrane-embedded peptides and proteins. The two major approaches are: (a) static or oriented solid-state NMR (170, 178–182), wherein nuclear anisotropic interactions are obtained from aligning samples with respect to the direction of the static magnetic field, and (b) magic angle spinning (MAS) NMR, whereby samples are spun at the magic angle ( θ ~ 54.7°) to remove the effects of chemical shift anisotropy and dipolar couplings (70, 173, 183–185). With fast spinning at the magic angle, resonances can reach line widths similar to those observed in solution NMR spectra.…”

Orientation and dynamics of transmembrane peptides: the power of simple models

“…Moreover, suitable labels can easily be incorporated during peptide synthesis, allowing the use of a wide range of biophysical techniques. For these reasons, synthetic peptides are becoming increasingly useful in the development and improvement of biophysical techniques to characterize membrane proteins/peptides (Andronesi et al 2004; Lemaitre et al 2004) and as models to understand the basic principles of peptide/protein-lipid interactions (Killian and Nyholm 2006; Shahidullah and London 2008; Yano et al 2002; Liu et al 2002; Mall et al 2000). In particular the WALP (depicted in Fig.…”

“…WALP peptides have been used for improving MD simulations, and for testing various new methods including NMR approaches (Vogel et al 2003; Lemaitre et al 2004; Andronesi et al 2004), EPR approaches (Nielsen et al 2005), and computational techniques (Im and Brooks 2005; Bond et al 2007; Ulmschneider et al 2009). …”

Investigation of Ligand‐Receptor Systems by High‐Resolution Solid‐State NMR: Recent Progress and Perspectives

“…These results demonstrate that, in addition to experimental approaches that utilize block or pattern labeled polypeptides under static or MAS conditions (see also for a recent review, reference [29]), 3D structures can be rapidly obtained using a single, uniformly labeled sample. Proton-mediated polarization transfer also offers new means to probe protein-protein interactions in high spectral resolution [30] and may, as recently demonstrated in the context of ( 13 C, 13 C) correlation spectroscopy [31], be applied to the structural study of macroscopically aligned samples under MAS conditions [32].…”