| Institution: | 1. Department of NMR based Structural Biology, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany
These authors contributed equally to this work.;2. Centre de RMN à Très Hauts Champs, Institut des Sciences Analytiques, UMR 5280/CNRS, ENS Lyon, UCB Lyon 1, Université de Lyon, Villeurbanne, France;3. Institute of Biochemical Engineering, Technical University of Munich, Boltzmannstraße 15, D-85748 Garching, Germany;4. Institute of Bioprocess Engineering, Friedrich-Alexander-Universität Erlangen-Nürnberg, Paul-Gordan-Straße 3, 91052 Erlangen, Germany;5. Department of NMR based Structural Biology, Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany |
| Abstract: | Determination of the environment surrounding a protein is often key to understanding its function and can also be used to infer the structural properties of the protein. By using proton-detected solid-state NMR, we show that reduced spin diffusion within the protein under conditions of fast magic-angle spinning, high magnetic field, and sample deuteration allows the efficient measurement of site-specific exposure to mobile water and lipids. We demonstrate this site specificity on two membrane proteins, the human voltage dependent anion channel, and the alkane transporter AlkL from Pseudomonas putida. Transfer from lipids is observed selectively in the membrane spanning region, and an average lipid-protein transfer rate of 6 s−1 was determined for residues protected from exchange. Transfer within the protein, as tracked in the 15N-1H 2D plane, was estimated from initial rates and found to be in a similar range of about 8 to 15 s−1 for several resolved residues, explaining the site specificity. |
