GFT NMR, a new approach to rapidly obtain precise high-dimensional NMR spectral information
GFT NMR, a new approach to rapidly obtain precise high-dimensional NMR spectral information
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DOI：
10.1021/ja028197d
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发表时间：
2003-02-05
影响因子：
15
通讯作者：
Szyperski, T
中科院分区：
文献类型：
--
作者：
Kim, S;Szyperski, T
广泛使用的高维傅立叶变换（FT）NMR光谱验证有两个主要缺点：（i）N维ft NMR实验的最小测量时间，这受到限制的限制，这可能会超过n-1间接尺寸，到目前为止，达到足够的信噪比所需的测量时间。 （ii）间接尺寸的低分辨率严重限制了间接化学移位测量值的精度。为了放宽这些缺点引起的约束，我们在这里提出了一种采集方案，该方案基于跨越常规NMR实验子空间的间接尺寸的相位敏感关节采样。这允许人们迅速获得高维的NMR光谱信息。由于相位敏感的关节采样产生包含“化学位数多重组”的物质，因此编辑多重组的组件需要替代数据处理。使用所谓的“ G-Matrix”线性合并物质，然后傅里叶转换。化学位移在构成偏移多重的谐振线中进行倍增。这对应于进行统计上独立的多个测量值，因此可以高精度地获得化学位移。为了表明使用了组合的G-Matrix和FT，我们将新方法命名为“ GFT NMR光谱”。 GFT NMR开放了新的途径，以建立高通量蛋白结构的确定，研究具有更高程度的化学位移退化性的系统，并研究动态现象，例如更详细的生物大分子对生物学大分子的缓慢折叠。
Widely used higher-dimensional Fourier transform (FT) NMR spectroscopy suffers from two major drawbacks: (i) The minimal measurement time of an N-dimensional FT NMR experiment, which is constrained by the need to sample N - 1 indirect dimensions, may exceed by far the measurement time required to achieve sufficient signal-to-noise ratios. (ii) The low resolution in the indirect dimensions severely limits the precision of the indirect chemical shift measurements. To relax on constraints arising from these drawbacks, we present here an acquisition scheme which is based on the phase-sensitive joint sampling of the indirect dimensions spanning a subspace of a conventional NMR experiment. This allows one to very rapidly obtain high-dimensional NMR spectral information. Because the phase-sensitive joint sampling yields subspectra containing "chemical shift multiplets", alternative data processing is required for editing the components of the multiplets. The subspectra are linearly combined using a so-called "G-matrix" and subsequently Fourier-transformed. The chemical shifts are multiply encoded in the resonance lines constituting the shift multiplets. This corresponds to performing statistically independent multiple measurements, and the chemical shifts can thus be obtained with high precision. To indicate that a combined G-matrix and FT is employed, we named the new approach "GFT NMR spectroscopy". GFT NMR opens new avenues to establish high-throughput protein structure determination, to investigate systems with a higher degree of chemical shift degeneracy, and to study dynamic phenomena such as slow folding of biological macromolecules in greater detail.