17 research outputs found
Post-synthetic Spin-Labeling of RNA through Click Chemistry for PELDOR Measurements
Siteâdirected spin labeling of RNA based on click chemistry is used in combination with pulsed electronâelectron double resonance (PELDOR) to benchmark a nitroxide spin label, called here dĆČ . We compare this approach with another established method that employs the rigid spin label Ăm for RNA labeling. By using CD spectroscopy, thermal denaturation measurements, CWâEPR as well as PELDOR we analyzed and compared the influence of dĆČ and Ăm on a selfâcomplementary RNA duplex. Our results demonstrate that the conformational diversity of dĆČ is significantly reduced near the freezing temperature of a phosphate buffer, resulting in strongly orientationâselective PELDOR time traces of the dĆČ âlabeled RNA duplex