We found a match
Your institution may have access to this item. Find your institution then sign in to continue.
- Title
Paramagnetic doping of a 7TM membrane protein in lipid bilayers by Gd³⁺-complexes for solid-state NMR spectroscopy.
- Authors
Ullrich, Sandra J; Hölper, Soraya; Glaubitz, Clemens
- Abstract
A considerable limitation of NMR spectroscopy is its inherent low sensitivity. Approximately 90 % of the measuring time is used by the spin system to return to its Boltzmann equilibrium after excitation, which is determined by (1)H-T1 in cross-polarized solid-state NMR experiments. It has been shown that sample doping by paramagnetic relaxation agents such as Cu(2+)-EDTA accelerates this process considerably resulting in enhanced sensitivity. Here, we extend this concept to Gd(3+)-complexes. Their effect on (1)H-T1 has been assessed on the membrane protein proteorhodopsin, a 7TM light-driven proton pump. A comparison between Gd(3+)-DOTA, Gd(3+)-TTAHA, covalently attached Cu(2+)-EDTA-tags and Cu(2+)-EDTA reveals a 3.2-, 2.6-, 2.4- and 2-fold improved signal-to-noise ratio per unit time due to longitudinal paramagnetic relaxation enhancement. Furthermore, Gd(3+)-DOTA shows a remarkably high relaxivity, which is 77-times higher than that of Cu(2+)-EDTA. Therefore, an order of magnitude lower dopant concentration can be used. In addition, no line-broadening effects or peak shifts have been observed on proteorhodopsin in the presence of Gd(3+)-DOTA. These favourable properties make it very useful for solid-state NMR experiments on membrane proteins.
- Publication
Journal of biomolecular NMR, 2014, Vol 58, Issue 1, p27
- ISSN
1573-5001
- Publication type
Journal Article
- DOI
10.1007/s10858-013-9800-4