Kay L E, Clore G M, Bax A, Gronenborn A M
Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892.
Science. 1990 Jul 27;249(4967):411-4. doi: 10.1126/science.2377896.
A method is presented that dramatically improves the resolution of protein nuclear magnetic resonance (NMR) spectra by increasing their dimensionality to four. The power of this technique is demonstrated by the application of four-dimensional carbon-13--nitrogen-15 (13C-15N)--edited nuclear Overhauser effect (NOE) spectroscopy to interleukin-1 beta, a protein of 153 residues. The NOEs between NH and aliphatic protons are first spread out into a third dimension by the 15N chemical shift of the amide 15N atom and subsequently into a fourth dimension by the 13C chemical shift of the directly bonded 13C atoms. By this means ambiguities in the assignment of NOEs between NH and aliphatic protons that are still present in the three-dimensional 15N-edited NOE spectrum due to extensive chemical shift overlap and degeneracy of aliphatic resonances are completely removed. Consequently, many more approximate interproton distance restraints can be obtained from the NOE data than was heretofore possible, thereby expanding the horizons of three-dimensional structure determination by NMR to larger proteins.
本文提出了一种方法，通过将蛋白质核磁共振（NMR）谱的维度增加到四维，显著提高其分辨率。将四维碳-13-氮-15（13C-15N）编辑的核Overhauser效应（NOE）光谱应用于含有153个残基的白细胞介素-1β，证明了该技术的强大功能。NH与脂肪族质子之间的NOE首先通过酰胺15N原子的15N化学位移扩展到第三维，随后通过直接相连的13C原子的13C化学位移扩展到第四维。通过这种方式，由于脂肪族共振的广泛化学位移重叠和简并性，在三维15N编辑的NOE谱中仍然存在的NH与脂肪族质子之间NOE归属的模糊性被完全消除。因此，与以往相比，可以从NOE数据中获得更多近似的质子间距离约束，从而将通过NMR确定三维结构的范围扩展到更大的蛋白质。
