Membrane incorporated synthetic a-helical polypeptides labelled with Dy(III) chelate complexes and nitroxide radicals were studied by the inversion recovery (IR) technique and Dy(III)-nitroxide distances were obtained. A comparison of obtained distances with the previously reported Gd(III)-nitroxide double electron–electron resonance (DEER) calibration data was performed and revealed reliability of the IR-based technique for the distance determination in membrane-incorporated biomacromolecules. The presented distance determination technique is ‘spectroscopically orthogonal’ to DEER-based distance measurements and can be potentially combined with DEER to study multiply spin-labelled biomacromolecules. The key steps of the data processing, the types of obtained distance information and the areas of possible application of the technique are discussed.
- pulsed dipolar esr
- epr spectroscopy
Lueders, P., Razzaghi, S., Jäger, H., Tschaggelar, R., Hemminga, M. A., Yulikov, M., & Jeschke, G. (2013). Distance determination from dysprosium induced relaxation enhancement: a case study on membrane-inserted WALP23 polypeptides. Molecular Physics, 111(18-19), 2824-2833. https://doi.org/10.1080/00268976.2013.806683