Solid-state NMR (SSNMR) is an attractive technique for studying large membrane proteins in membrane-mimetic environments. However, SSNMR experiments often suffer from low efficiency, due to the inherent low sensitivity and the long recycle delays needed to recover the magnetization. Here we demonstrate that the incorporation of a small amount of a Gd3+-chelated lipid, Gd3+-DMPE-DTPA, into proteoliposomes greatly shortens the spinâ??lattice relaxation time (1H-T 1) of lipid-reconstituted membrane proteins and accelerates the data collection. This effect has been evaluated on a 30Â*kDa, seven-transmembrane protein, Leptosphaeria rhodopsin. With the Gd3+-chelated lipid, we can perform 2D SSNMR experiments 3 times faster than by diamagnetic control. By combining this paramagnetic relaxation-assisted data collection with non-uniform sampling, the 3D experimental times are reduced eightfold with respect to traditional 3D experiments on diamagnetic samples. A comparison between the paramagnetic relaxation enhancement (PRE) effects of Cu2+- and Gd3+-chelated lipids indicates the much higher relaxivity of the latter. Hence, a tenfold lower concentration is needed for Gd3+-chelated lipids to achieve comparable PRE effects to Cu2+-chelated lipids. In addition, Gd3+-chelated lipids neither alter the protein structures nor induce significant line-width broadening of the protein signals. This work is expected to be beneficial for structural and dynamic studies of large membrane proteins by SSNMR.
Shortening spin-lattice relaxation using a copper-chelated lipid at low-temperatures - A magic angle spinning solid-state NMR study on a membrane-bound protein
From The DNP-NMR Blog:
Shortening spin-lattice relaxation using a copper-chelated lipid at low-temperatures - A magic angle spinning solid-state NMR study on a membrane-bound protein
This article is not about DNP. However, the authors describe how to use paramagnetic relaxation enhancers to speed up the data acquisition and with this increase the sensitivity. A similar effect happens when a paramagnetic polarization agent is used in a DNP-NMR experiment and often the only reason why it is actually possible to run 1H-DNP-NMR experiments with recycling delays of several seconds...
[NMR paper] Shortening spin-lattice relaxation using a copper-chelated lipid at low-temperatures - A magic angle spinning solid-state NMR study on a membrane-bound protein.
Shortening spin-lattice relaxation using a copper-chelated lipid at low-temperatures - A magic angle spinning solid-state NMR study on a membrane-bound protein.
Related Articles Shortening spin-lattice relaxation using a copper-chelated lipid at low-temperatures - A magic angle spinning solid-state NMR study on a membrane-bound protein.
J Magn Reson. 2013 Nov 1;237C:175-181
Authors: Yamamoto K, Caporini MA, Im S, Waskell L, Ramamoorthy A
Abstract
Inherent low sensitivity of NMR spectroscopy has been a major disadvantage, especially to...
nmrlearner
Journal club
0
11-20-2013 12:52 PM
[NMR paper] Shortening Spin-lattice Relaxation Using a Copper-Chelated lipid at Low-Temperatures – A Magic Angle Spinning Solid-State NMR Study on a Membrane-Bound Protein
Shortening Spin-lattice Relaxation Using a Copper-Chelated lipid at Low-Temperatures – A Magic Angle Spinning Solid-State NMR Study on a Membrane-Bound Protein
Publication date: Available online 1 November 2013
Source:Journal of Magnetic Resonance</br>
Author(s): Kazutoshi Yamamoto , Marc Caporini , Sangchoul Im , Lucy Waskell , Ayyalusamy Ramamoorthy</br>
Inherent low sensitivity of NMR spectroscopy has been a major disadvantage, especially to study biomolecules like membrane proteins. Recent studies have successfully demonstrated the advantages of performing...
nmrlearner
Journal club
0
11-01-2013 03:48 AM
Solid-State NMR Investigations of Peptide-Lipid Interactions of the Transmembrane Domain of A Plant-Derived Protein, Hcf106
Solid-State NMR Investigations of Peptide-Lipid Interactions of the Transmembrane Domain of A Plant-Derived Protein, Hcf106
Publication date: Available online 24 September 2013
Source:Chemistry and Physics of Lipids</br>
Author(s): Lei Zhang , Lishan Liu , Sergey Maltsev , Gary A. Lorigan , Carole Dabney-Smith</br>
The chloroplast twin arginine translocation system transports highly folded precursor proteins across the thylakoid using the protonmotive force as its only energy source. Hcf106 and another thylakoid protein, cpTatC compose the precursor receptor...
nmrlearner
Journal club
0
09-25-2013 11:15 AM
Structure and dynamics of the lipid modifications of a transmembrane ?-helical peptide determined by (2)H solid-state NMR spectroscopy.
Structure and dynamics of the lipid modifications of a transmembrane ?-helical peptide determined by (2)H solid-state NMR spectroscopy.
Structure and dynamics of the lipid modifications of a transmembrane ?-helical peptide determined by (2)H solid-state NMR spectroscopy.
Biochim Biophys Acta. 2010 Dec 28;
Authors: Penk A, Müller M, Scheidt HA, Langosch D, Huster D
The fusion of biological membranes is mediated by integral membrane proteins with ?-helical transmembrane segments. Additionally, those proteins are often modified by the covalent...