Morshauser R C, Zuiderweg E R
Department of Biological Chemistry, Department of Chemistry, University of Michigan, 930 North University Avenue, Ann Arbor, Michigan 48109, USA.
J Magn Reson. 1999 Aug;139(2):232-9. doi: 10.1006/jmre.1999.1802.
Practical optimization of the 4D [(1)H, (13)C, (13)C, (1)H] HMQC-NOESY-HSQC experiment in terms of distribution of resolution over the indirect dimensions is analyzed in detail. Recommendations for an optimal experiment are based on computer simulations assessing the effective resolution of the experiment, defined as the percentage of all possible NOE cross peaks that can be assigned unambiguously on the basis of the spectral data alone. Using actual (13)C-(1)H spectra of an 18-kDa chaperone protein, the analysis shows that experiments with the best effective resolution are also among the most sensitive ones. When combined with an efficient aliasing scheme that reduces indirect spectral space 124-fold, a 4D experiment that yields unambiguous assignments for 41% of all possible NOE cross peaks can be recorded in 28 h. A high-resolution experiment, which can be recorded in 8 days, yields 61% unambiguous assignments and can be analyzed more easily using standard NMR display software. The predictions are verified with experimental 4D spectra from which 1850 NOEs (914 long-range) were extracted for the 18-kDa chaperone protein.
详细分析了4D [(1)H, (13)C, (13)C, (1)H] HMQC-NOESY-HSQC实验在间接维度上分辨率分布的实际优化情况。关于最佳实验的建议基于计算机模拟，该模拟评估了实验的有效分辨率，有效分辨率定义为仅根据光谱数据就能明确归属的所有可能的NOE交叉峰的百分比。使用一种18 kDa伴侣蛋白的实际(13)C-(1)H光谱，分析表明具有最佳有效分辨率的实验也是最灵敏的实验之一。当与一种能将间接光谱空间减少124倍的有效混叠方案相结合时，一个能对所有可能的NOE交叉峰的41%进行明确归属的4D实验可在28小时内记录完成。一个可在8天内记录完成的高分辨率实验能产生61%的明确归属，并且使用标准NMR显示软件更容易进行分析。这些预测通过实验4D光谱得到了验证，从该光谱中提取了针对18 kDa伴侣蛋白的1850个NOE（914个长程）。
