Bartucci Rosa, Aloi Erika
Department of Chemistry and Chemical Technologies, University of Calabria, Rende (CS), Italy.
Molecular Biophysics Laboratory, Department of Physics, University of Calabria, Rende (CS), Italy.
Front Mol Biosci. 2022 Jun 29;9:923794. doi: 10.3389/fmolb.2022.923794. eCollection 2022.
Methods of electron spin echo of pulse electron paramagnetic resonance (EPR) spectroscopy are increasingly employed to investigate biophysical properties of nitroxide-labeled biosystems at cryogenic temperatures. Two-pulse echo-detected ED-spectra have proven to be valuable tools to describe the librational dynamics in the low-temperature phases of both lipids and proteins in membranes. The motional parameter, , given by the product of the mean-square angular amplitude, , and the rotational correlation time, , of the motion, is readily determined from the nitroxide ED-spectra as well as from the -relaxation rate curves. An independent evaluation of is obtained from the motionally averaged N-hyperfine splitting separation in the continuous wave cw-EPR spectra. Finally, the rotational correlation time can be estimated by combining ED- and cw-EPR data. In this mini-review, results on the librational dynamics in model and natural membranes are illustrated.
脉冲电子顺磁共振（EPR）光谱的电子自旋回波方法越来越多地用于研究低温下氮氧化物标记生物系统的生物物理性质。两脉冲回波检测的ED光谱已被证明是描述膜中脂质和蛋白质低温相中的振动动力学的有价值工具。运动参数 由运动的均方角振幅 与旋转相关时间 的乘积给出，可从氮氧化物ED光谱以及 弛豫速率曲线轻松确定。从连续波cw-EPR光谱中的运动平均N-超精细分裂分离可获得 的独立评估。最后，通过结合ED和cw-EPR数据可以估计旋转相关时间 。在本微型综述中，展示了模型膜和天然膜中振动动力学的结果。
