title: New developments in spin labels for pulsed dipolar EPR.
abstract: Spin labelling is a chemical technique that enables the integration of a molecule containing an unpaired electron into another framework for study. Given the need to understand the structure, dynamics, and conformational changes of biomacromolecules, spin labelling provides a relatively non-intrusive technique and has certain advantages over X-ray crystallography; which requires high quality crystals. The technique relies on the design of binding probes that target a functional group, for example, the thiol group of a cysteine residue within a protein. The unpaired electron is typically supplied through a nitroxide radical and sterically shielded to preserve stability. Pulsed electron paramagnetic resonance (EPR) techniques allow small magnetic couplings to be measured (e.g., <50 MHz) providing information on single label probes or the dipolar coupling between multiple labels. In particular, distances between spin labels pairs can be derived which has led to many protein/enzymes and nucleotides being studied. Here, we summarise recent examples of spin labels used for pulse EPR that serve to illustrate the contribution of chemistry to advancing discoveries in this field.
authors.affiliation: School of Chemistry and the Photon Science Institute, The University of Manchester, Oxford Road, Manchester M13 9PL, UK. alistair.fielding@manchester.ac.uk.
authors.forename: Alistair J
authors.initials: AJ
authors.lastname: Fielding
authors.affiliation: School of Chemistry and the Photon Science Institute, The University of Manchester, Oxford Road, Manchester M13 9PL, UK.
authors.forename: Maria Grazia
authors.initials: MG
authors.lastname: Concilio
authors.affiliation: School of Chemistry and the Photon Science Institute, The University of Manchester, Oxford Road, Manchester M13 9PL, UK.
authors.forename: Graham
authors.initials: G
authors.lastname: Heaven
authors.affiliation: School of Chemistry and the Photon Science Institute, The University of Manchester, Oxford Road, Manchester M13 9PL, UK.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Hollas
mesh_terms: D000818:Animals; D004578:Electron Spin Resonance Spectroscopy; D006801:Humans; D046911:Macromolecular Substances / Q000737:chemistry*; D013113:Spin Labels
chemical_list: D046911:Macromolecular Substances; D013113:Spin Labels