脉冲偶极耦合EPR技术在生物大分子结构变化与互作研究中的应用

doi:10.11938/cjmr20253191

摘要/Abstract

摘要：

脉冲偶极耦合电子顺磁共振（PD-EPR）技术是一种研究蛋白质等生物大分子结构变化与相互作用的重要生物物理技术．该技术通过测量定点引入到目标分子上的自旋探针之间未成对电子的偶极相互作用，直接获取纳米尺度下电子自旋之间的距离分布信息，并通过比较不同实验条件下自旋对间的距离分布，解析生物大分子的结构变化、互作与动态行为．本文系统综述了三种主要的PD-EPR技术包括双电子-电子共振（DEER）、双量子相干（DQC）和弛豫诱导偶极调制增强（RIDME）的基本原理、技术特点及相关应用，总结了PD-EPR研究中常用的自旋探针类型及蛋白质标记策略，重点介绍了近年来该技术在生物大分子及其复合物研究中的最新进展．

关键词: 脉冲偶极耦合EPR, 蛋白质动态结构, 自旋标记, 生物大分子, 双电子-电子共振

Abstract:

Pulsed dipolar electron paramagnetic resonance (PD-EPR) is a powerful biophysical technique for probing the dynamic structures and interactions of biomacromolecules such as proteins. By measuring dipolar interactions between unpaired electrons, PD-EPR directly yields nanometer-scale distance distributions between electron spins, from which conformational transitions can be inferred by comparison under different experimental conditions. This review summarizes three major PD-EPR techniques, including double electron-electron resonance, double quantum coherence, and relaxation-induced dipolar modulation enhancement, together with commonly used spin labels and protein spin-labeling strategies, highlighting recent advances in the study of biomacromolecules and complexes.

Key words: pulsed dipolar EPR, protein dynamic structures, spin labeling, biomacromolecules, DEER

中图分类号:

O482.53

谢雅欣, 杨茵, 苏循成. 脉冲偶极耦合EPR技术在生物大分子结构变化与互作研究中的应用[J]. 波谱学杂志, 2026, 43(3): 350-366.

XIE Yaxin, YANG Yin, SU Xuncheng. Applications of Pulsed Dipolar EPR Spectroscopy in Characterizing Interactions and Structural Changes of Biomacromolecules[J]. Chinese Journal of Magnetic Resonance, 2026, 43(3): 350-366.

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r/nm	t_max/μs
2	0.15
3	0.52
4	1.23
5	2.39
6	4.14
7	6.57
8	9.81

技术方法	微波频率要求	样品要求	主要优势	主要局限	适用自旋探针类型
DEER	双频微波	避免浓度过高导致背景增强	方法成熟，应用最广；软件支持完善	仪器要求高；要求自旋谱线具有足够频率分离	氮氧自由基、Mn²⁺、Gd³⁺等
DQC	单频微波	要求自旋具有较长相干时间	理论灵敏度高；适合低浓度样品；可用于谱线重叠体系	实验脉冲序列复杂；对样品相干时间敏感	氮氧自由基、三苯甲基自由基为主
RIDME	单频微波	T₁不宜过短	对宽谱、快速弛豫的体系具有显著优势	易受核调制干扰	顺磁性金属离子、三苯甲基自由基