Simorre J P, Brutscher B, Caffrey M S, Marion D
Institut de Biologie Structurale, CNRS-CEA, Grenoble, France.
J Biomol NMR. 1994 May;4(3):325-33. doi: 10.1007/BF00179343.
Two-dimensional versions of HNCA and HNCO experiments are described, which provide essentially the same information as the 3D sequence. A multiple-quantum coherence involving either 15N and 13C alpha or 15N and 13CO is created. One of the two frequencies is given by the middle point between the two cross peaks (zero- and double-quantum) and the other by their separation. Quadrature detection can be performed on either nucleus, modifying only the appearance of the 2D spectrum, but not the information content. These experiments, named MQ-HNCA and MQ-HNCO, are illustrated on a (15N, 13C) doubly labelled cytochrome c2 from Rhodobacter capsulatus (116 amino acids).
描述了HNCA和HNCO实验的二维版本，它们提供与三维序列基本相同的信息。创建了一个涉及15N和13Cα或15N和13CO的多量子相干。两个频率中的一个由两个交叉峰（零量子和双量子）之间的中点给出，另一个由它们的间距给出。可以对任一原子核进行正交检测，这只会改变二维谱的外观，而不会改变信息内容。这些实验被命名为MQ-HNCA和MQ-HNCO，并在来自荚膜红细菌的（15N，13C）双标记细胞色素c2（116个氨基酸）上进行了展示。
