Dvinskikh Sergey, Dürr Ulrich, Yamamoto Kazutoshi, Ramamoorthy Ayyalusamy
Biophysics Research Division and Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA.
J Am Chem Soc. 2006 May 17;128(19):6326-7. doi: 10.1021/ja061153a.
Bicelles are increasingly being used as membrane mimicking systems in NMR experiments to investigate the structure of membrane proteins. In this study, we demonstrate the effectiveness of a 2D solid-state NMR approach that can be used to measure the structural constraints, such as heteronuclear dipolar couplings between 1H, 13C, and 31P nuclei, in bicelles without the need for isotopic enrichment. This method does not require a high radio frequency power unlike the presently used rotating-frame separated-local-field (SLF) techniques, such as PISEMA. In addition, multiple dipolar couplings can be measured accurately, and the presence of a strong dipolar coupling does not suppress the weak couplings. High-resolution spectra obtained from magnetically aligned DMPC:DHPC bicelles even in the presence of peptides suggest that this approach will be useful in understanding lipid-protein interactions that play a vital role in shaping up the function of membrane proteins.
双分子层囊泡越来越多地被用作核磁共振实验中的膜模拟系统，以研究膜蛋白的结构。在本研究中，我们展示了一种二维固态核磁共振方法的有效性，该方法可用于测量双分子层囊泡中的结构约束，如1H、13C和31P核之间的异核偶极耦合，而无需同位素富集。与目前使用的旋转框架分离局部场（SLF）技术（如PISEMA）不同，该方法不需要高射频功率。此外，可以准确测量多个偶极耦合，并且强偶极耦合的存在不会抑制弱耦合。即使在存在肽的情况下，从磁取向的DMPC:DHPC双分子层囊泡获得的高分辨率光谱表明，这种方法将有助于理解在塑造膜蛋白功能中起关键作用的脂-蛋白相互作用。
