The Journal of Physical Chemistry B · 2015 · 50 citations · 23 references
Life SciencesBiochemistryChemistryProtein BiochemistrySpectroscopyStructural BiologyMacromolecular Structure DeterminationProtein CharacterizationProtein DynamicsProtein MotifsProtein StructureSpectroscopy Of BiomoleculesMetal-binding PropertiesMetal-binding ProteinsNanometer-scale ImagingParamagnetic CentersParamagnetic SpeciesProtein Dynamics AnalysisProtein Labeling ChemistryProtein Secondary Structure Analysis
Double electron electron resonance (DEER) is an attractive technique that is utilized for gaining insight into protein structure and dynamics via nanometer-scale distance measurements. The most commonly used paramagnetic tag in these measurements is a nitroxide spin label, R1. Here, we present the application of two types of high-affinity Cu(2+) chelating tags, based on the EDTA and cyclen metal-binding motifs as alternative X-band DEER probes, using the B1 immunoglobulin-binding domain of protein G (GB1) as a model system. Both types of tags have been incorporated into a variety of protein secondary structure environments and exhibit high spectral sensitivity. In particular, the cyclen-based tag displays distance distributions with comparable distribution widths and most probable distances within 1-3 Å when compared to homologous R1 distributions. The results display the viability of the cyclen tag as an alternative to the R1 side chain for X-band DEER distance measurements in proteins.
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A Novel, Highly Stable Fold of the Immunoglobulin Binding Domain of Streptococcal Protein G
Angela M. Gronenborn, David Filpula, Nina Z. Essig et al. · Science · 1991 · 826 citations