Spatiotemporal Resolution of Conformational Changes in Biomolecules by Combining Pulsed Electron-Electron Double Resonance Spectroscopy with Microsecond Freeze-Hyperquenching

The function of proteins is linked to their conformations that can be resolved with several high-resolution methods. However, only a few methods can provide the temporal order of intermediates and conformational changes, with each having its limitations. Here, we combine pulsed electron-electron double resonance spectroscopy with a microsecond freeze-hyperquenching setup to achieve spatiotemporal resolution in the angstrom range and lower microsecond time scale. We show that the conformational change of the C-alpha-helix in the cyclic nucleotide-binding domain of the Mesorhizobium loci potassium channel occurs within about 150 mu s and can be resolved with angstrom precision. Thus, this approach holds great promise for obtaining 4D landscapes of conformational changes in biomolecules.

Automated summary

The study combines pulsed electron-electron double resonance spectroscopy with a microsecond freeze-hyperquenching setup to achieve spatial and temporal resolution in the angstrom range and lower microsecond time scale. The conformational change of the C-alpha helix in the cyclic nucleotide-binding domain of the Mesorhizobium loci potassium channel occurs within about 150 microseconds and can be resolved with angstrom precision, showing great promise for obtaining 4D landscapes of conformational changes in biomolecules.