Giraud Nicolas, Blackledge Martin, Böckmann Anja, Emsley Lyndon
Laboratoire de Chimie (UMR 5182 CNRS/ENS Lyon), Ecole Normale Supérieure de Lyon, Lyon, France.
J Magn Reson. 2007 Jan;184(1):51-61. doi: 10.1016/j.jmr.2006.09.015. Epub 2006 Oct 9.
The effect of nitrogen-15 proton-driven spin diffusion on quantitative (15)N T(1) measurements in solid proteins is investigated, and the impact on the measurement of dynamic parameters is assessed. A simple model of exchange between neighboring nitrogens is used to reproduce the evolution of (15)N spin systems whose longitudinal relaxation rates and exchange rates are compatible with experimental measurements. We show that the induced error in the measured T(1) and its effect on the determination of dynamics parameters is likely to be less than the current experimental error. The use of deuterated protein samples is shown to have a small but sometimes visible effect, and may also considerably slow down or even suppress the exchange of magnetization due to spin diffusion.
研究了氮-15质子驱动的自旋扩散对固体蛋白质中定量（15）N T（1）测量的影响，并评估了其对动力学参数测量的影响。使用相邻氮之间交换的简单模型来再现（15）N自旋系统的演化，其纵向弛豫率和交换率与实验测量值相符。我们表明，测量的T（1）中引入的误差及其对动力学参数测定的影响可能小于当前的实验误差。结果表明，使用氘代蛋白质样品有微小但有时可见的影响，并且还可能显著减慢甚至抑制由于自旋扩散引起的磁化交换。
