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Abstract
Spin labelling enables the study of biomolecules using electron paramagnetic resonance (EPR) spectroscopy. Here, we describe the synthesis of a cysteine-reactive spin label based on a spirocyclic pyrrolidinyl nitroxide containing an iodoacetamide moiety. The spin label was shown to be highly persistent under reducing conditions while maintaining excellent EPR relaxation parameters up to a temperature of 180 K. After successful double spin labelling of a calmodulin variant, interspin distances were measured by the electron paramagnetic resonance (EPR) spectroscopy experiment double electron-electron resonance (DEER) at 120 K.
Supplementary materials
Title
Supplementary Information
Description
Experimental details and procedures, compound characterisation, crystallography details, preparation of spin labelled protein, NMR and EPR data.
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Supplementary weblinks
Title
Replication Data for: Sigmatropic rearrangement enables access to a highly stable spirocyclic nitroxide for protein spin labelling
Description
Raw data, including NMR and EPR spectra, kinetics studies, relaxation data, crystallography data.
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