NMR has matured into a technique routinely employed for studying proteins in near physiological conditions. However, applications to larger proteins are impeded by the complexity of the various correlation maps necessary to assign NMR signals. This article reviews the data analysis techniques traditionally employed for resonance assignment and describes alternative protocols necessary for overcoming challenges in large protein spectra. In particular, simultaneous analysis of multiple spectra may help overcome ambiguities or may reveal correlations in an indirect manner. Similarly, visualization of orthogonal planes in a multidimensional spectrum can provide alternative assignment procedures. We describe examples of such strategies for assignment of backbone, methyl, and nOe resonances. We describe experimental aspects of data acquisition for the related experiments and provide guidelines for preliminary studies. Focus is placed on large folded monomeric proteins and examples are provided for 37, 48, 53, and 81 kDa proteins.

中文翻译：

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较大且具有挑战性的蛋白质中 NMR 信号分配的实际问题

核磁共振已经成熟成为一种常规用于在接近生理条件下研究蛋白质的技术。然而，分配 NMR 信号所需的各种相关图的复杂性阻碍了对较大蛋白质的应用。本文回顾了传统上用于共振分配的数据分析技术，并描述了克服大蛋白质光谱挑战所需的替代方案。特别是，多个光谱的同时分析可能​​有助于克服歧义或可以以间接方式揭示相关性。类似地，多维谱中正交平面的可视化可以提供替代的分配过程。我们描述了这种分配主链、甲基和 nOe 共振的策略的例子。我们描述了相关实验的数据采集的实验方面，并为初步研究提供了指导。重点关注大折叠单体蛋白质，并提供 37、48、53 和 81 kDa 蛋白质的示例。