Carr P A, Fearing D A, Palmer A G
Department of Biochemistry and Molecular Biophysics, Columbia University, New York, New York 10032, USA.
J Magn Reson. 1998 May;132(1):25-33. doi: 10.1006/jmre.1998.1374.
An experimental approach for the measurement of nuclear magnetic spin relaxation rate constants that combines triple-resonance techniques and accordion spectroscopy is described. Pulse sequences are discussed for the measurement of backbone 15N and 13CO R1 relaxation rate constants. The three-dimensional HNCO triple-resonance technique is employed to gain improved spectral resolution over conventional two-dimensional methods by frequency labeling both the 15N and 13CO spins. Accordion spectroscopy is used to reduce the dimensionality of the relaxation experiment. The "negative-time accordion" approach (A. M. Mandel and A. G. Palmer (1994), J. Magn. Reson. A 110, 62-72) is used for extracting rate constants from the t1 interferograms. The experiments are demonstrated using a 13C/15N isotopically enriched sample of the third fibronectin type III domain of human tenascin.
描述了一种结合三重共振技术和手风琴光谱法测量核磁共振自旋弛豫速率常数的实验方法。讨论了用于测量主链15N和13CO R1弛豫速率常数的脉冲序列。采用三维HNCO三重共振技术,通过对15N和13CO自旋进行频率标记,比传统二维方法获得更高的光谱分辨率。手风琴光谱法用于降低弛豫实验的维度。“负时间手风琴”方法(A. M. 曼德尔和A. G. 帕尔默(1994年),《磁共振杂志A》110,62 - 72)用于从t1干涉图中提取速率常数。使用人腱生蛋白第三III型纤连蛋白结构域的13C/15N同位素富集样品进行了实验演示。