Department of Chemistry and Francis Bitter Magnet Laboratory, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States.
Department of Biochemistry and Structural Biology, Lund University , Lund 221 00, Sweden.
J Am Chem Soc. 2017 May 17;139(19):6518-6521. doi: 10.1021/jacs.7b01159. Epub 2017 May 3.
We demonstrate a novel 3D NNC magic angle spinning NMR experiment that generates N-N internuclear contacts in protein systems using an optimized N-N proton assisted recoupling (PAR) mixing period and a C dimension for improved resolution. The optimized PAR condition permits the acquisition of high signal-to-noise 3D data that enables backbone chemical shift assignments using a strategy that is complementary to current schemes. The spectra can also provide distance constraints. The utility of the experiment is demonstrated on an MAβ fibril sample that yields high-quality data that is readily assigned and interpreted. The 3D NNC experiment therefore provides a powerful platform for solid-state protein studies and is broadly applicable to a variety of systems and experimental conditions.
我们展示了一种新颖的 3D NNC 魔角旋转 NMR 实验，该实验使用优化的 N-N 质子辅助重聚（PAR）混合周期和 C 维度生成蛋白质系统中的 N-N 核间接触，以提高分辨率。优化的 PAR 条件允许采集高信噪比的 3D 数据，该数据可使用与当前方案互补的策略进行骨架化学位移分配。该光谱还可以提供距离约束。该实验在 MAβ 原纤维样品上的应用证明了它的实用性，该样品可获得易于分配和解释的高质量数据。因此，3D NNC 实验为固态蛋白质研究提供了一个强大的平台，并且广泛适用于各种系统和实验条件。
