EPR Distance Measurements as a Tool to Characterize Protein‐DNA Interactions

Abstract Over recent decades, electron paramagnetic resonance (EPR) spectroscopy has become an essential tool for exploring complex biological systems. Herein, we discuss the potential of pulsed EPR spectroscopy to shed light on the mechanisms of protein‐DNA interactions. To this end, we first provide an overview of pulsed EPR methodology (and specifically, double electron electron resonance; DEER), with a focus on the various spin‐labeling methods used today both for protein labeling and for DNA labeling. Next, after briefly discussing recent applications of DEER in protein‐DNA studies, we introduce a detailed case study, an example of how EPR spectroscopy has been used to resolve the transcription mechanism of the CueR copper regulator.