101
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Bekö SL, Thoms SD, Schmidt MU. 4,4'-{Diazenediylbis[(1,4-phenylene)bis(carbonyloxy)]}bis(2,2,6,6-tetramethylpiperidinyloxidanyl): the first crystal structure determination from powder data of a nitroxide radical. Acta Crystallogr C 2013; 69:1513-5. [PMID: 24311502 DOI: 10.1107/s0108270113029211] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2013] [Accepted: 10/23/2013] [Indexed: 11/10/2022] Open
Abstract
The title compound, C32H42N4O6, is a novel nitroxide radical used for pulsed electron-electron double resonance (PELDOR) spectroscopy. Its crystal structure was determined from laboratory X-ray powder diffraction data. The attractive forces between the molecules in the crystal structure are mainly of dispersive nature. A special interaction of the nitroxide radicals was not observed.
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Affiliation(s)
- Sándor L Bekö
- Institute of Inorganic and Analytical Chemistry, Goethe University, Max-von-Laue-Strasse 7, D-60438 Frankfurt am Main, Germany
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102
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Kattnig DR, Reichenwallner J, Hinderberger D. Modeling Excluded Volume Effects for the Faithful Description of the Background Signal in Double Electron–Electron Resonance. J Phys Chem B 2013; 117:16542-57. [DOI: 10.1021/jp408338q] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | - Jörg Reichenwallner
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
- Institute
of Chemistry, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz
4, 06120 Halle (Saale), Germany
| | - Dariush Hinderberger
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
- Institute
of Chemistry, Martin-Luther-Universität Halle-Wittenberg, Von-Danckelmann-Platz
4, 06120 Halle (Saale), Germany
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103
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Branigan E, Pliotas C, Hagelueken G, Naismith JH. Quantification of free cysteines in membrane and soluble proteins using a fluorescent dye and thermal unfolding. Nat Protoc 2013; 8:2090-7. [PMID: 24091556 PMCID: PMC3836627 DOI: 10.1038/nprot.2013.128] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Cysteine is an extremely useful site for selective attachment of labels to proteins for many applications, including the study of protein structure in solution by electron paramagnetic resonance (EPR), fluorescence spectroscopy and medical imaging. The demand for quantitative data for these applications means that it is important to determine the extent of the cysteine labeling. The efficiency of labeling is sensitive to the 3D context of cysteine within the protein. Where the label or modification is not directly measurable by optical or magnetic spectroscopy, for example, in cysteine modification to dehydroalanine, assessing labeling efficiency is difficult. We describe a simple assay for determining the efficiency of modification of cysteine residues, which is based on an approach previously used to determine membrane protein stability. The assay involves a reaction between the thermally unfolded protein and a thiol-specific coumarin fluorophore that is only fluorescent upon conjugation with thiols. Monitoring fluorescence during thermal denaturation of the protein in the presence of the dye identifies the temperature at which the maximum fluorescence occurs; this temperature differs among proteins. Comparison of the fluorescence intensity at the identified temperature between modified, unmodified (positive control) and cysteine-less protein (negative control) allows for the quantification of free cysteine. We have quantified both site-directed spin labeling and dehydroalanine formation. The method relies on a commonly available fluorescence 96-well plate reader, which rapidly screens numerous samples within 1.5 h and uses <100 μg of material. The approach is robust for both soluble and detergent-solubilized membrane proteins.
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Affiliation(s)
- Emma Branigan
- Biomedical Sciences Research Complex, University of St. Andrews, St. Andrews, UK
| | - Christos Pliotas
- Biomedical Sciences Research Complex, University of St. Andrews, St. Andrews, UK
| | - Gregor Hagelueken
- Biomedical Sciences Research Complex, University of St. Andrews, St. Andrews, UK
| | - James H Naismith
- Biomedical Sciences Research Complex, University of St. Andrews, St. Andrews, UK
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104
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Tsvetkov YD. Nitroxyls and PELDOR: Nitroxyl radicals in pulsed electron-electron double resonance spectroscopy. J STRUCT CHEM+ 2013. [DOI: 10.1134/s0022476613070044] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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105
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Milov AD, Tsvetkov YD, De Zotti M, Prinzivalli C, Biondi B, Formaggio F, Toniolo C, Gobbo M. Aggregation modes of the spin mono-labeled tylopeptin B and heptaibin peptaibiotics in frozen solutions of weak polarity as studied by PELDOR spectroscopy. J STRUCT CHEM+ 2013. [DOI: 10.1134/s0022476613070056] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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106
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Giannoulis A, Ward R, Branigan E, Naismith JH, Bode BE. PELDOR in rotationally symmetric homo-oligomers. Mol Phys 2013; 111:2845-2854. [PMID: 24954956 PMCID: PMC4056887 DOI: 10.1080/00268976.2013.798697] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2013] [Revised: 04/12/2013] [Indexed: 12/24/2022]
Abstract
Nanometre distance measurements by pulsed electron-electron double resonance (PELDOR) spectroscopy have become an increasingly important tool in structural biology. The theoretical underpinning of the experiment is well defined for systems containing two nitroxide spin-labels (spin pairs); however, recently experiments have been reported on homo-oligomeric membrane proteins consisting of up to eight spin-labelled monomers. We have explored the theory behind these systems by examining model systems based on multiple spins arranged in rotationally symmetric polygons. The results demonstrate that with a rising number of spins within the test molecule, increasingly strong distortions appear in distance distributions obtained from an analysis based on the simple spin pair approach. These distortions are significant over a range of system sizes and remain so even when random errors are introduced into the symmetry of the model. We present an alternative approach to the extraction of distances on such systems based on a minimisation that properly treats multi-spin correlations. We demonstrate the utility of this approach on a spin-labelled mutant of the heptameric Mechanosensitive Channel of Small Conductance of E. coli.
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Affiliation(s)
- Angeliki Giannoulis
- EaStCHEM School of Chemistry, University of St Andrews, North Haugh, St Andrews, Fife, KY16 9ST, Scotland, UK
- Biomedical Sciences Research Complex, University of St Andrews, North Haugh, St Andrews, Fife, KY16 9ST, Scotland, UK
- Centre of Magnetic Resonance, University of St Andrews, North Haugh, St Andrews, Fife, KY16 9ST, Scotland, UK
| | - Richard Ward
- Biomedical Sciences Research Complex, University of St Andrews, North Haugh, St Andrews, Fife, KY16 9ST, Scotland, UK
- Centre of Magnetic Resonance, University of St Andrews, North Haugh, St Andrews, Fife, KY16 9ST, Scotland, UK
| | - Emma Branigan
- Biomedical Sciences Research Complex, University of St Andrews, North Haugh, St Andrews, Fife, KY16 9ST, Scotland, UK
| | - James H. Naismith
- Biomedical Sciences Research Complex, University of St Andrews, North Haugh, St Andrews, Fife, KY16 9ST, Scotland, UK
| | - Bela E. Bode
- EaStCHEM School of Chemistry, University of St Andrews, North Haugh, St Andrews, Fife, KY16 9ST, Scotland, UK
- Biomedical Sciences Research Complex, University of St Andrews, North Haugh, St Andrews, Fife, KY16 9ST, Scotland, UK
- Centre of Magnetic Resonance, University of St Andrews, North Haugh, St Andrews, Fife, KY16 9ST, Scotland, UK
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107
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Myers WK, Xu X, Li C, Lagerstedt JO, Budamagunta MS, Voss JC, Britt RD, Ames JB. Double electron-electron resonance probes Ca²⁺-induced conformational changes and dimerization of recoverin. Biochemistry 2013; 52:5800-8. [PMID: 23906368 DOI: 10.1021/bi400538w] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Recoverin, a member of the neuronal calcium sensor (NCS) branch of the calmodulin superfamily, is expressed in retinal photoreceptor cells and serves as a calcium sensor in vision. Ca²⁺-induced conformational changes in recoverin cause extrusion of its covalently attached myristate (termed Ca²⁺-myristoyl switch) that promotes translocation of recoverin to disk membranes during phototransduction in retinal rod cells. Here we report double electron-electron resonance (DEER) experiments on recoverin that probe Ca²⁺-induced changes in distance as measured by the dipolar coupling between spin-labels strategically positioned at engineered cysteine residues on the protein surface. The DEER distance between nitroxide spin-labels attached at C39 and N120C is 2.5 ± 0.1 nm for Ca²⁺-free recoverin and 3.7 ± 0.1 nm for Ca²⁺-bound recoverin. An additional DEER distance (5-6 nm) observed for Ca²⁺-bound recoverin may represent an intermolecular distance between C39 and N120. ¹⁵N NMR relaxation analysis and CW-EPR experiments both confirm that Ca²⁺-bound recoverin forms a dimer at protein concentrations above 100 μM, whereas Ca²⁺-free recoverin is monomeric. We propose that Ca²⁺-induced dimerization of recoverin at the disk membrane surface may play a role in regulating Ca²⁺-dependent phosphorylation of dimeric rhodopsin. The DEER approach will be useful for elucidating dimeric structures of NCS proteins in general for which Ca²⁺-induced dimerization is functionally important but not well understood.
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Affiliation(s)
- William K Myers
- Department of Chemistry, University of California, Davis, California 95616, United States
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108
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Dzuba SA, Raap J. Spin-Echo Electron Paramagnetic Resonance (EPR) Spectroscopy of a Pore-Forming (Lipo)Peptaibol in Model and Bacterial Membranes. Chem Biodivers 2013; 10:864-75. [DOI: 10.1002/cbdv.201200387] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2012] [Indexed: 11/08/2022]
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109
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Kattnig DR, Hinderberger D. Analytical distance distributions in systems of spherical symmetry with applications to double electron-electron resonance. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2013; 230:50-63. [PMID: 23454574 DOI: 10.1016/j.jmr.2013.01.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Revised: 01/24/2013] [Accepted: 01/25/2013] [Indexed: 05/24/2023]
Abstract
Based on a simple geometrical approach, we derive analytical expression of the probability density functions (pdfs) of distance of probe molecules distributed homogeneously in spherical aggregates with shell structure. These distance distributions can be utilized in the investigation of double electron-electron resonance (DEER) data of disordered nanometer-sized spin clusters. Structural insights and geometrical parameters of the aggregates can be extracted by modeling the DEER time traces based on the analytical pdfs. This approach is efficient and avoids difficulties of the model-free solution of the inverse problem that are related to multi-spin effects, limited excitation bandwidth, bias introduced by the regularization scheme, or ambiguity resulting from broad distance distributions. The derived pdfs can serve as building blocks, from which the distance distributions in arbitrary spherically symmetric objects can be assembled. The scenario of the pumped species being chemically distinct from the observed species is covered as well as that of a single type of probe molecules. We demonstrate the merits of analytical distance distributions by studying the distribution of three different spin probes in SDS micelles. By simultaneously analyzing DEER data corresponding to different spin probe concentrations, the distribution of the spin probes over the micelle can be determined. Employing Bayesian inference it is found that for all probes studied, a spherical shell model is most appropriate among the studied models and by orders of magnitude more likely than a homogeneous distribution in a ball. This statement also applies to probes that are deemed nonpolar. We envisage that the spin probe distributions in disordered soft and hard matter systems can now be quantified using DEER spectroscopy with greater precision and reduced ambiguity.
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Affiliation(s)
- Daniel R Kattnig
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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110
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Reichenwallner J, Hinderberger D. Using bound fatty acids to disclose the functional structure of serum albumin. Biochim Biophys Acta Gen Subj 2013; 1830:5382-93. [PMID: 23643928 DOI: 10.1016/j.bbagen.2013.04.031] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Revised: 04/23/2013] [Accepted: 04/24/2013] [Indexed: 11/16/2022]
Abstract
BACKGROUND Serum albumin is a major transport protein in mammals and is known to have at least seven binding sites for long-chain fatty acids (FAs). SCOPE OF REVIEW We have devised a new electron paramagnetic resonance (EPR) spectroscopic approach to gain information on the functional structure of serum albumin in solution in a "coarse-grained" manner from the ligands' point of view. Our approach is based on using spin labeled (paramagnetic) stearic acids self-assembled with albumin and subsequent nanoscale distance measurements between the FAs using double electron-electron resonance spectroscopy (DEER). Simple continuous wave (CW) EPR spectroscopy, which allows for quantification of bound ligands, complements our studies. MAJOR CONCLUSIONS Based on DEER nanoscale distance measurements, the functional solution structure of human serum albumin (HSA) has remarkably been found to have a much more symmetric distribution of entry points to the FA binding sites than expected from the crystal structure, indicating increased surface flexibility and plasticity for HSA in solution. In contrast, for bovine serum albumin (BSA), the entry point topology is in good agreement with that expected from the crystal structure of HSA. Changes in the solution structures between albumins can hence be revealed and extended to more albumins to detect functional differences at the nanoscale. Going beyond fundamental structural studies, our research platform is also excellently suited for general studies of protein-solvent interactions, temperature effects and ligand binding. GENERAL SIGNIFICANCE We discuss how our research platform helps illuminate protein dynamics and function and can be used to characterize albumin-based hybrid materials. This article is part of a Special Issue entitled Serum Albumin.
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Affiliation(s)
- Jörg Reichenwallner
- Max Planck Institute for Polymer Research, Ackermannweg 10, D-55128 Mainz, Germany; Institute for Pharmacy and Biochemistry, Johannes Gutenberg-Universität Mainz, Johann-Joachim-Becher-Weg 30, D-55128 Mainz, Germany
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111
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Spindler PE, Glaser SJ, Skinner TE, Prisner TF. Broadband Inversion PELDOR Spectroscopy with Partially Adiabatic Shaped Pulses. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201207777] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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112
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Spindler PE, Glaser SJ, Skinner TE, Prisner TF. Broadband inversion PELDOR spectroscopy with partially adiabatic shaped pulses. Angew Chem Int Ed Engl 2013; 52:3425-9. [PMID: 23424088 DOI: 10.1002/anie.201207777] [Citation(s) in RCA: 96] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2012] [Indexed: 12/14/2022]
Affiliation(s)
- Philipp E Spindler
- Institut für physikalische und theoretische Chemie und Biomolekulares Magnetresonanz Zentrum, Universität Frankfurt, Max-von-Laue-Strasse 7, 60438 Frankfurt am Main, Germany
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113
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von Hagens T, Polyhach Y, Sajid M, Godt A, Jeschke G. Suppression of ghost distances in multiple-spin double electron–electron resonance. Phys Chem Chem Phys 2013; 15:5854-66. [DOI: 10.1039/c3cp44462g] [Citation(s) in RCA: 70] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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114
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Zhang W, Tyl M, Ward R, Sobott F, Maman J, Murthy AS, Watson AA, Fedorov O, Bowman A, Owen-Hughes T, EL-Mkami H, Murzina NV, Norman D, Laue ED. Structural plasticity of histones H3-H4 facilitates their allosteric exchange between RbAp48 and ASF1. Nat Struct Mol Biol 2013; 20:29-35. [PMID: 23178455 PMCID: PMC3538076 DOI: 10.1038/nsmb.2446] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2012] [Accepted: 10/05/2012] [Indexed: 12/22/2022]
Abstract
The mechanisms by which histones are disassembled and reassembled into nucleosomes and chromatin structure during DNA replication, repair and transcription are poorly understood. A better understanding of the processes involved is, however, crucial if we are to understand whether and how histone variants and post-translationally modified histones are inherited in an epigenetic manner. To this end we have studied the interaction of the histone H3-H4 complex with the human retinoblastoma-associated protein RbAp48 and their exchange with a second histone chaperone, anti-silencing function protein 1 (ASF1). Exchange of histones H3-H4 between these two histone chaperones has a central role in the assembly of new nucleosomes, and we show here that the H3-H4 complex has an unexpected structural plasticity, which is important for this exchange.
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Affiliation(s)
- Wei Zhang
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, CB2 1GA, United Kingdom
| | - Marek Tyl
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, CB2 1GA, United Kingdom
| | - Richard Ward
- Nucleic Acids Research Group, School of Life Sciences, MSI/WTB Complex, Dow St., Dundee, DD1 5EH, United Kingdom
| | - Frank Sobott
- Department of Chemistry, Centre for Proteomics, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp, Belgium
| | - Joseph Maman
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, CB2 1GA, United Kingdom
| | - Andal S. Murthy
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, CB2 1GA, United Kingdom
| | - Aleksandra A. Watson
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, CB2 1GA, United Kingdom
| | - Oleg Fedorov
- The Structural Genomics Consortium, University of Oxford, Old Road Campus Research Building, Roosevelt Drive, Oxford, OX3 7DQ, United Kingdom
| | - Andrew Bowman
- Wellcome Trust Centre for Gene Regulation and Expression, College of Life Sciences, University of Dundee, Dundee, DD1 5EH, United Kingdom
| | - Tom Owen-Hughes
- Wellcome Trust Centre for Gene Regulation and Expression, College of Life Sciences, University of Dundee, Dundee, DD1 5EH, United Kingdom
| | - Hassane EL-Mkami
- Millimetre wave and EPR Group, School of Physics and Astronomy , University of St Andrews, North Haugh, St Andrews, KY16 9SS, United Kingdom
| | - Natalia V. Murzina
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, CB2 1GA, United Kingdom
| | - David Norman
- Nucleic Acids Research Group, School of Life Sciences, MSI/WTB Complex, Dow St., Dundee, DD1 5EH, United Kingdom
| | - Ernest D. Laue
- Department of Biochemistry, University of Cambridge, 80 Tennis Court Road, Cambridge, CB2 1GA, United Kingdom
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115
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Borbat PP, Freed JH. Pulse Dipolar Electron Spin Resonance: Distance Measurements. STRUCTURAL INFORMATION FROM SPIN-LABELS AND INTRINSIC PARAMAGNETIC CENTRES IN THE BIOSCIENCES 2013. [DOI: 10.1007/430_2012_82] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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116
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Bhatnagar J, Sircar R, Borbat PP, Freed JH, Crane BR. Self-association of the histidine kinase CheA as studied by pulsed dipolar ESR spectroscopy. Biophys J 2012; 102:2192-201. [PMID: 22824284 DOI: 10.1016/j.bpj.2012.03.038] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2011] [Revised: 02/29/2012] [Accepted: 03/12/2012] [Indexed: 11/26/2022] Open
Abstract
Biologically important protein complexes often involve molecular interactions that are low affinity or transient. We apply pulsed dipolar electron spin resonance spectroscopy and site-directed spin labeling in what to our knowledge is a new approach to study aggregation and to identify regions on protein surfaces that participate in weak, but specific molecular interactions. As a test case, we have probed the self-association of the chemotaxis kinase CheA, which forms signaling clusters with chemoreceptors and the coupling protein CheW at the poles of bacterial cells. By measuring the intermolecular dipolar interactions sensed by spin-labels distributed over the protein surface, we show that the soluble CheA kinase aggregates to a small extent through interactions mediated by its regulatory (P5) domain. Direct dipolar distance measurements confirm that a hydrophobic surface at the periphery of P5 subdomain 2 associates CheA dimers in solution. This result is further supported by differential disulfide cross-linking from engineered cysteine reporter sites. We suggest that the periphery of P5 is an interaction site on CheA for other similar hydrophobic surfaces and plays an important role in structuring the signaling particle.
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Affiliation(s)
- Jaya Bhatnagar
- Advanced Center for ESR Studies (ACERT), Cornell University, Ithaca, NY, USA
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117
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Reginsson GW, Kunjir NC, Sigurdsson ST, Schiemann O. Trityl radicals: spin labels for nanometer-distance measurements. Chemistry 2012; 18:13580-4. [PMID: 22996284 DOI: 10.1002/chem.201203014] [Citation(s) in RCA: 99] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2012] [Indexed: 12/11/2022]
Abstract
Spin labelling with trityls: to gather information about the structure and dynamics of trityl radicals, spin-labelled polymers were measured with pulsed electron-electron double resonance (PELDOR) and double-quantum coherence (DQC). This study demonstrates that trityl radicals have great potential as spin labels that eliminate some limitations of nitroxide spin labels.
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Affiliation(s)
- Gunnar W Reginsson
- Biomedical Sciences Research Complex, Centre of Magnetic Resonance, St. Andrews, UK
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118
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Conformational state of the MscS mechanosensitive channel in solution revealed by pulsed electron-electron double resonance (PELDOR) spectroscopy. Proc Natl Acad Sci U S A 2012; 109:E2675-82. [PMID: 23012406 DOI: 10.1073/pnas.1202286109] [Citation(s) in RCA: 78] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
The heptameric mechanosensitive channel of small conductance (MscS) provides a critical function in Escherichia coli where it opens in response to increased bilayer tension. Three approaches have defined different closed and open structures of the channel, resulting in mutually incompatible models of gating. We have attached spin labels to cysteine mutants on key secondary structural elements specifically chosen to discriminate between the competing models. The resulting pulsed electron-electron double resonance (PELDOR) spectra matched predicted distance distributions for the open crystal structure of MscS. The fit for the predictions by structural models of MscS derived by other techniques was not convincing. The assignment of MscS as open in detergent by PELDOR was unexpected but is supported by two crystal structures of spin-labeled MscS. PELDOR is therefore shown to be a powerful experimental tool to interrogate the conformation of transmembrane regions of integral membrane proteins.
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119
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Nakazawa S, Nishida S, Ise T, Yoshino T, Mori N, Rahimi RD, Sato K, Morita Y, Toyota K, Shiomi D, Kitagawa M, Hara H, Carl P, Höfer P, Takui T. A Synthetic Two-Spin Quantum Bit:g-Engineered Exchange-Coupled Biradical Designed for Controlled-NOT Gate Operations. Angew Chem Int Ed Engl 2012. [DOI: 10.1002/ange.201204489] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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120
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Reginsson GW, Shelke SA, Rouillon C, White MF, Sigurdsson ST, Schiemann O. Protein-induced changes in DNA structure and dynamics observed with noncovalent site-directed spin labeling and PELDOR. Nucleic Acids Res 2012; 41:e11. [PMID: 22941643 PMCID: PMC3592447 DOI: 10.1093/nar/gks817] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
Site-directed spin labeling and pulsed electron-electron double resonance (PELDOR or DEER) have previously been applied successfully to study the structure and dynamics of nucleic acids. Spin labeling nucleic acids at specific sites requires the covalent attachment of spin labels, which involves rather complicated and laborious chemical synthesis. Here, we use a noncovalent label strategy that bypasses the covalent labeling chemistry and show that the binding specificity and efficiency are large enough to enable PELDOR or DEER measurements in DNA duplexes and a DNA duplex bound to the Lac repressor protein. In addition, the rigidity of the label not only allows resolution of the structure and dynamics of oligonucleotides but also the determination of label orientation and protein-induced conformational changes. The results prove that this labeling strategy in combination with PELDOR has a great potential for studying both structure and dynamics of oligonucleotides and their complexes with various ligands.
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Affiliation(s)
- Gunnar W Reginsson
- Biomedical Sciences Research Complex, Centre of Magnetic Resonance, University of St Andrews, St Andrews KY16 9ST, UK
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121
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Nakazawa S, Nishida S, Ise T, Yoshino T, Mori N, Rahimi RD, Sato K, Morita Y, Toyota K, Shiomi D, Kitagawa M, Hara H, Carl P, Höfer P, Takui T. A Synthetic Two-Spin Quantum Bit:g-Engineered Exchange-Coupled Biradical Designed for Controlled-NOT Gate Operations. Angew Chem Int Ed Engl 2012; 51:9860-4. [DOI: 10.1002/anie.201204489] [Citation(s) in RCA: 100] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2012] [Revised: 08/06/2012] [Indexed: 12/20/2022]
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122
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Cunningham TF, McGoff MS, Sengupta I, Jaroniec CP, Horne WS, Saxena S. High-resolution structure of a protein spin-label in a solvent-exposed β-sheet and comparison with DEER spectroscopy. Biochemistry 2012; 51:6350-9. [PMID: 22809334 DOI: 10.1021/bi300328w] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
X-ray crystallography has been a useful tool in the development of site-directed spin labeling by resolving rotamers of the nitroxide spin-label side chain in a variety of α-helical environments. In this work, the crystal structure of a doubly spin-labeled N8C/K28C mutant of the B1 immunoglobulin-binding domain of protein G (GB1) was solved. The double mutant formed a domain-swapped dimer under crystallization conditions. Two rotameric states of the spin-label were resolved at the solvent-exposed α-helical site, at residue 28; these are in good agreement with rotamers previously reported for helical structures. The second site, at residue 8 on an interior β-strand, shows the presence of three distinct solvent-exposed side-chain rotamers. One of these rotamers is rarely observed within crystal structures of R1 sites and suggests that the H(α) and S(δ) hydrogen bond that is common to α-helical sites is absent at this interior β-strand residue. Variable temperature continuous wave (CW) experiments of the β-strand site showed two distinct components that were correlated to the rotameric states observed in crystallography. Interestingly, the CW data at room temperature could be fit without the use of an order parameter, which is consistent with the lack of the H(α) and S(δ) interaction. Additionally, double electron electron resonance (DEER) spectroscopy was performed on the GB1 double mutant in its monomeric form and yielded a most probable interspin distance of 25 ± 1 Å. In order to evaluate the accuracy of the measured DEER distance, the rotamers observed in the crystal structure of the domain-swapped GB1 dimer were modeled into a high-resolution structure of the wild type monomeric GB1. The distances generated in the resulting GB1 structural models match the most probable DEER distance within ~2 Å. The results are interesting as they indicate by direct experimental measurement that the rotameric states of R1 found in this crystal provide a very close match to the most probable distance measured by DEER.
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Affiliation(s)
- Timothy F Cunningham
- Department of Chemistry, University of Pittsburgh, 219 Parkman Avenue, Pittsburgh, PA 15260, USA
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123
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End-to-End Distance Determination in a Cucurbit[6]uril-Based Rotaxane by PELDOR Spectroscopy. Chemphyschem 2012; 13:2659-61. [DOI: 10.1002/cphc.201200103] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2012] [Revised: 04/27/2012] [Indexed: 11/07/2022]
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124
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Abstract
Distance distributions between paramagnetic centers in the range of 1.8 to 6 nm in membrane proteins and up to 10 nm in deuterated soluble proteins can be measured by the DEER technique. The number of paramagnetic centers and their relative orientation can be characterized. DEER does not require crystallization and is not limited with respect to the size of the protein or protein complex. Diamagnetic proteins are accessible by site-directed spin labeling. To characterize structure or structural changes, experimental protocols were optimized and techniques for artifact suppression were introduced. Data analysis programs were developed, and it was realized that interpretation of the distance distributions must take into account the conformational distribution of spin labels. First methods have appeared for deriving structural models from a small number of distance constraints. The present scope and limitations of the technique are illustrated.
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Affiliation(s)
- Gunnar Jeschke
- Laboratory of Physical Chemistry, Eidgenössische Technische Hochschule Zürich, Switzerland.
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125
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Akdogan Y, Hinderberger D. Solvent-Induced Protein Refolding at Low Temperatures. J Phys Chem B 2011; 115:15422-9. [DOI: 10.1021/jp209646f] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yasar Akdogan
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Dariush Hinderberger
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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126
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Spiess HW. Addendum to the paper "Dead-time free measurement of dipole-dipole interactions between electron spins" by M. Pannier, S. Veit, A. Godt, G. Jeschke, and H.W. Spiess [J. Magn. Reson. 142 (2000) 331-340]. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2011; 213:326-328. [PMID: 21890390 DOI: 10.1016/j.jmr.2011.08.014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The development of four-pulse DEER as described, which has been published in the Journal of Magnetic Resonance more than 10 years ago. The corresponding paper is an example where a slight advance, such as adding a refocusing pulse, which in retrospect looks so simple, can have a remarkable impact on an entire field of science. In our case it offered a simple way to exact measurements of distances between defined species in the nanometer range. The current applications are mainly in determining structures of proteins and nucleic acids.
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127
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Flaender M, Sicoli G, Aci-Seche S, Reignier T, Maurel V, Saint-Pierre C, Boulard Y, Gambarelli S, Gasparutto D. A triple spin-labeling strategy coupled with DEER analysis to detect DNA modifications and enzymatic repair. Chembiochem 2011; 12:2560-3. [PMID: 21984076 DOI: 10.1002/cbic.201100550] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2011] [Indexed: 12/20/2022]
Abstract
In a spin: Spin-labeled oligonucleotides produced by click chemistry can be studied by EPR, by using a DEER sequence. This was used to test a complex triple-labeling strategy with damaged DNA. Extensive and accurate analysis of DNA structure and enzymatic repair processes were performed after digestion by EndoIV. Modified DNA structures and DNA-protein interactions can now be readily studied.
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Affiliation(s)
- Mélanie Flaender
- Institut Nanoscience et Cryogénie, Laboratoire de Chimie Inorganique et Biologique, UMR-E n°3 CEA-UJF, CEA-Grenoble, 17 Avenue des Martyrs, 38054 Grenoble Cedex 9, France
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128
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129
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Mesopores provide an amorphous state suitable for studying biomolecular structures at cryogenic temperatures. Proc Natl Acad Sci U S A 2011; 108:14145-50. [PMID: 21844377 DOI: 10.1073/pnas.1102395108] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In nano-confinements, aqueous solutions can be found to remain in a liquid state at subfreezing temperatures. The finding provides a means of entering into previously inaccessible temperature regions for studying the dynamics and structure of bulk liquid. Here we show that studying biomolecular structures in nano-confinements improves the accuracy of cryostructures and provides better insight into the relationship between hydration water and biomolecules. Synthetic prion protein peptides are studied in two experimental conditions: (i) in confined nanochannels within mesoporous materials, and (ii) in vitrified bulk solvents, with a temperature range of 50-275 K, using cw/pulse ESR techniques. A large inhomogeneous lineshape broadening is only observed for the spectra from the vitrified bulk solvent below 70 K, suggesting a possible peptide clustering in the solution. The spin-counting and distance measurements by DEER-ESR provide further evidence that peptides are dispersed homogeneously in mesopores but heterogeneously in vitrified solvents wherein the biomolecular structure is disturbed due to heterogeneity in the bulk solvent structure. Our study demonstrates that the nanospace within mesoporous materials provides an amorphous environment that is better than vitrified bulk solvent for studying biostructures at cryogenic temperatures.
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130
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Bode BE, Dastvan R, Prisner TF. Pulsed electron-electron double resonance (PELDOR) distance measurements in detergent micelles. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2011; 211:11-17. [PMID: 21474348 DOI: 10.1016/j.jmr.2011.03.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/21/2010] [Revised: 03/09/2011] [Accepted: 03/14/2011] [Indexed: 05/30/2023]
Abstract
Pulsed electron-electron double resonance (PELDOR) spectroscopy is a powerful tool for measuring nanometer distances in spin-labeled systems. A common approach is doubly covalent spin-labeling of a macromolecule and measurement of the inter-spin distance, or to use singly-labeled components of a system that forms aggregates or oligomers. This situation has been described as a spin-cluster. The PELDOR signal, however, does not only contain the desired dipolar coupling between the spin-labels of the molecule or cluster under study. In samples of finite concentration the dipolar coupling between the spin-labels of the randomly distributed molecules or spin-clusters also contributes significantly. In homogeneous frozen solutions or lipid vesicle membranes this second contribution can be considered to be an exponential or stretched exponential decay, respectively. In this study, we show that this assumption is not valid in detergent micelles. Spin-labeled fatty acids that are randomly partitioned into different detergent micelles give rise to PELDOR time traces which clearly deviate from stretched exponential decays. The obtained signals can be modeled quantitatively based on the size of the micelles, their aggregation number, the spin-label concentration and the degree of spin-labeling. As a main conclusion a PELDOR signal deviating from a stretched exponential decay does not necessarily prove the observation of specific distance information on the molecule or cluster. These results are important for the interpretation of PELDOR experiments on membrane proteins or lipophilic peptides solubilized in detergent micelles or small vesicles, which often do not show pronounced dipolar oscillations in their time traces.
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Affiliation(s)
- Bela E Bode
- Institute of Physical and Theoretical Chemistry and Center for Biomolecular Magnetic Resonance, Goethe University, Max-von-Laue-Strasse 7, 60438 Frankfurt am Main, Germany
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131
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Junk MJN, Spiess HW, Hinderberger D. DEER in biological multispin-systems: a case study on the fatty acid binding to human serum albumin. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2011; 210:210-217. [PMID: 21450500 DOI: 10.1016/j.jmr.2011.03.003] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2010] [Revised: 12/14/2010] [Accepted: 03/02/2011] [Indexed: 05/30/2023]
Abstract
In this study, self-assembled systems of human serum albumin (HSA) and spin-labeled fatty acids are characterized by double electron-electron resonance (DEER). HSA, being the most important transport protein of the human blood, is capable to host up to seven paramagnetic fatty acid derivatives. DEER measurements of these self-assembled multispin clusters are strongly affected by correlations of more than two spins, the evaluation of the latter constituting the central topic of this paper. While the DEER modulation depth can be used to obtain qualitative information of the number of coupled spins, the quantitative analysis is hampered by the occurrence of cluster mixtures with different numbers of coupled spins and contributions from unbound spin-labeled material. Applying flip angle dependent DEER measurements, unwanted multispin correlations were found to lead not only to a broadening of the distance peaks but also to cause small distances to be overestimated and large distances to be suppressed. It is thus favorable to use spin-diluted systems with an average of two paramagnetic molecules per spin cluster when a quantitative analysis of the distance distribution is sought.
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Affiliation(s)
- Matthias J N Junk
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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132
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Song Y, Meade TJ, Astashkin A, Klein E, Enemark J, Raitsimring A. Pulsed dipolar spectroscopy distance measurements in biomacromolecules labeled with Gd(III) markers. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2011; 210:59-68. [PMID: 21388847 PMCID: PMC3081411 DOI: 10.1016/j.jmr.2011.02.010] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Revised: 02/03/2011] [Accepted: 02/08/2011] [Indexed: 05/11/2023]
Abstract
This work demonstrates the feasibility of using Gd(III) tags for long-range Double Electron Electron Resonance (DEER) distance measurements in biomacromolecules. Double-stranded 14- base pair Gd(III)-DNA conjugates were synthesized and investigated at K(a) band. For the longest Gd(III) tag the average distance and average deviation between Gd(III) ions determined from the DEER time domains was about 59±12Å. This result demonstrates that DEER measurements with Gd(III) tags can be routinely carried out for distances of at least 60Å, and analysis indicates that distance measurements up to 100Å are possible. Compared with commonly used nitroxide labels, Gd(III)-based labels will be most beneficial for the detection of distance variations in large biomacromolecules, with an emphasis on large scale changes in shape or distance. Tracking the folding/unfolding and domain interactions of proteins and the conformational changes in DNA are examples of such applications.
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Affiliation(s)
- Y. Song
- Departments of Chemistry; Molecular Biosciences; Neurobiology & Physiology; and Radiology, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA
| | - T. J. Meade
- Departments of Chemistry; Molecular Biosciences; Neurobiology & Physiology; and Radiology, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA
| | - A.V. Astashkin
- Department of Chemistry and Biochemistry, University of Arizona, 1306 E. University Blvd., Tucson, Arizona 85721-0041, USA
| | - E.L. Klein
- Department of Chemistry and Biochemistry, University of Arizona, 1306 E. University Blvd., Tucson, Arizona 85721-0041, USA
| | - J.H. Enemark
- Department of Chemistry and Biochemistry, University of Arizona, 1306 E. University Blvd., Tucson, Arizona 85721-0041, USA
| | - A. Raitsimring
- Department of Chemistry and Biochemistry, University of Arizona, 1306 E. University Blvd., Tucson, Arizona 85721-0041, USA
- Corresponding Author: Arnold Raitsimring, Department of Chemistry and Biochemistry, University of Arizona, 1306 E. University Blvd., Tucson, Arizona 85721-0041, USA.
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133
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Pulsed electron-electron double resonance: beyond nanometre distance measurements on biomacromolecules. Biochem J 2011; 434:353-63. [PMID: 21348855 DOI: 10.1042/bj20101871] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
PELDOR (or DEER; pulsed electron-electron double resonance) is an EPR (electron paramagnetic resonance) method that measures via the dipolar electron-electron coupling distances in the nanometre range, currently 1.5-8 nm, with high precision and reliability. Depending on the quality of the data, the error can be as small as 0.1 nm. Beyond mere mean distances, PELDOR yields distance distributions, which provide access to conformational distributions and dynamics. It can also be used to count the number of monomers in a complex and allows determination of the orientations of spin centres with respect to each other. If, in addition to the dipolar through-space coupling, a through-bond exchange coupling mechanism contributes to the overall coupling both mechanisms can be separated and quantified. Over the last 10 years PELDOR has emerged as a powerful new biophysical method without size restriction to the biomolecule to be studied, and has been applied to a large variety of nucleic acids as well as proteins and protein complexes in solution or within membranes. Small nitroxide spin labels, paramagnetic metal ions, amino acid radicals or intrinsic clusters and cofactor radicals have been used as spin centres.
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134
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Krstić I, Hänsel R, Romainczyk O, Engels JW, Dötsch V, Prisner TF. Long-Range Distance Measurements on Nucleic Acids in Cells by Pulsed EPR Spectroscopy. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201100886] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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135
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Krstić I, Hänsel R, Romainczyk O, Engels JW, Dötsch V, Prisner TF. Long-range distance measurements on nucleic acids in cells by pulsed EPR spectroscopy. Angew Chem Int Ed Engl 2011; 50:5070-4. [PMID: 21506223 DOI: 10.1002/anie.201100886] [Citation(s) in RCA: 139] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2011] [Indexed: 12/18/2022]
Affiliation(s)
- Ivan Krstić
- Institute of Physical and Theoretical Chemistry and Center for Biomolecular Magnetic Resonance (BMRZ), Goethe University Frankfurt, Max-von-Laue-Str. 7, 60438 Frankfurt am Main, Germany
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136
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Akdogan Y, Junk MJN, Hinderberger D. Effect of Ionic Liquids on the Solution Structure of Human Serum Albumin. Biomacromolecules 2011; 12:1072-9. [DOI: 10.1021/bm1014156] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yasar Akdogan
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Matthias J. N. Junk
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Dariush Hinderberger
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
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137
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Studying biomolecular complexes with pulsed electron–electron double resonance spectroscopy. Biochem Soc Trans 2011; 39:128-39. [DOI: 10.1042/bst0390128] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The function of biomolecules is intrinsically linked to their structure and the complexes they form during function. Techniques for the determination of structures and dynamics of these nanometre assemblies are therefore important for an understanding on the molecular level. PELDOR (pulsed electron–electron double resonance) is a pulsed EPR method that can be used to reliably and precisely measure distances in the range 1.5–8 nm, to unravel orientations and to determine the number of monomers in complexes. In conjunction with site-directed spin labelling, it can be applied to biomolecules of all sizes in aqueous solutions or membranes. PELDOR is therefore complementary to the methods of X-ray crystallography, NMR and FRET (fluorescence resonance energy transfer) and is becoming a powerful method for structural determination of biomolecules. In the present review, the methods of PELDOR are discussed and examples where PELDOR has been used to obtain structural information on biomolecules are summarized.
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138
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Jeschke G. Interpretation of Dipolar EPR Data in Terms of Protein Structure. STRUCTURAL INFORMATION FROM SPIN-LABELS AND INTRINSIC PARAMAGNETIC CENTRES IN THE BIOSCIENCES 2011. [DOI: 10.1007/430_2011_61] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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139
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Abstract
Intrinsically disordered proteins (IDPs) form a unique protein category characterized by the absence of a well-defined structure and by remarkable conformational flexibility. Electron Paramagnetic Resonance (EPR) spectroscopy combined with site-directed spin labeling (SDSL) is amongst the most suitable methods to unravel their structure and dynamics. This review summarizes the tremendous methodological developments in the area of SDSL EPR and its applications in protein research. Recent results on the intrinsically disordered Parkinson's disease protein α-synuclein illustrate that the method has gained increasing attention in IDP research. SDSL EPR has now reached a level where broad application in this rapidly advancing field is feasible.
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Affiliation(s)
- Malte Drescher
- Department of Chemistry, University of Konstanz, Konstanz, Germany.
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140
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Krstić I, Endeward B, Margraf D, Marko A, Prisner TF. Structure and dynamics of nucleic acids. Top Curr Chem (Cham) 2011; 321:159-98. [PMID: 22160388 DOI: 10.1007/128_2011_300] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
In this chapter we describe the application of CW and pulsed EPR methods for the investigation of structural and dynamical properties of RNA and DNA molecules and their interaction with small molecules and proteins. Special emphasis will be given to recent applications of dipolar spectroscopy on nucleic acids.
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Affiliation(s)
- Ivan Krstić
- Goethe University Frankfurt, Frankfurt am Main, Germany
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141
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Gordon-Grossman M, Kaminker I, Gofman Y, Shai Y, Goldfarb D. W-Band pulse EPR distance measurements in peptides using Gd3+–dipicolinic acid derivatives as spin labels. Phys Chem Chem Phys 2011; 13:10771-80. [DOI: 10.1039/c1cp00011j] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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142
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Margraf D, Bode BE, Marko A, Schiemann O, Prisner TF. Conformational flexibility of nitroxide biradicals determined by X-band PELDOR experiments. Mol Phys 2010. [DOI: 10.1080/00268970701724982] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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143
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Dastvan R, Bode BE, Karuppiah MPR, Marko A, Lyubenova S, Schwalbe H, Prisner TF. Optimization of Transversal Relaxation of Nitroxides for Pulsed Electron−Electron Double Resonance Spectroscopy in Phospholipid Membranes. J Phys Chem B 2010; 114:13507-16. [DOI: 10.1021/jp1060039] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Reza Dastvan
- Institute of Physical and Theoretical Chemistry, Institute of Organic Chemistry and Chemical Biology, and Center for Biomolecular Magnetic Resonance, Goethe University, Max-von-Laue-Strasse 7, 60438 Frankfurt am Main, Germany
| | - Bela E. Bode
- Institute of Physical and Theoretical Chemistry, Institute of Organic Chemistry and Chemical Biology, and Center for Biomolecular Magnetic Resonance, Goethe University, Max-von-Laue-Strasse 7, 60438 Frankfurt am Main, Germany
| | - Muruga Poopathi Raja Karuppiah
- Institute of Physical and Theoretical Chemistry, Institute of Organic Chemistry and Chemical Biology, and Center for Biomolecular Magnetic Resonance, Goethe University, Max-von-Laue-Strasse 7, 60438 Frankfurt am Main, Germany
| | - Andriy Marko
- Institute of Physical and Theoretical Chemistry, Institute of Organic Chemistry and Chemical Biology, and Center for Biomolecular Magnetic Resonance, Goethe University, Max-von-Laue-Strasse 7, 60438 Frankfurt am Main, Germany
| | - Sevdalina Lyubenova
- Institute of Physical and Theoretical Chemistry, Institute of Organic Chemistry and Chemical Biology, and Center for Biomolecular Magnetic Resonance, Goethe University, Max-von-Laue-Strasse 7, 60438 Frankfurt am Main, Germany
| | - Harald Schwalbe
- Institute of Physical and Theoretical Chemistry, Institute of Organic Chemistry and Chemical Biology, and Center for Biomolecular Magnetic Resonance, Goethe University, Max-von-Laue-Strasse 7, 60438 Frankfurt am Main, Germany
| | - Thomas F. Prisner
- Institute of Physical and Theoretical Chemistry, Institute of Organic Chemistry and Chemical Biology, and Center for Biomolecular Magnetic Resonance, Goethe University, Max-von-Laue-Strasse 7, 60438 Frankfurt am Main, Germany
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144
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Potapov A, Song Y, Meade TJ, Goldfarb D, Astashkin A, Raitsimring A. Distance measurements in model bis-Gd(III) complexes with flexible "bridge". Emulation of biological molecules having flexible structure with Gd(III) labels attached. JOURNAL OF MAGNETIC RESONANCE (SAN DIEGO, CALIF. : 1997) 2010; 205:38-49. [PMID: 20418132 PMCID: PMC2885582 DOI: 10.1016/j.jmr.2010.03.019] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2009] [Revised: 03/30/2010] [Accepted: 03/30/2010] [Indexed: 05/18/2023]
Abstract
In this work, we continue to explore Gd(III) as a possible spin label for high-field Double Electron-Electron Resonance (DEER) based distance measurements in biological molecules with flexible geometry. For this purpose, a bis-Gd(III) complex with a flexible "bridge" was used as a model. The distances in the model were expected to be distributed in the range of 5-26 A, allowing us to probe the shortest limits of accessible distances which were found to be as small as 13 A. The upper distance limit for these labels was also evaluated and was found to be about 60 A. Various pulse duration setups can result in apparent differences in the distribution function derived from DEER kinetics due to short distance limit variations. The advantages, such as the ability to perform measurements at cryogenic temperatures and high repetition rates simultaneously, the use of very short pumping and observation pulses without mutual interference, the lack of orientational selectivity, as well as the shortcomings, such as the limited mw operational frequency range and intrinsically smaller amplitude of oscillation related to dipolar interaction as compared with nitroxide spin labels are discussed. Most probably the use of nitroxide and Gd-based labels for distance measurements will be complementary depending on the particulars of the problem and the availability of instrumentation.
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Affiliation(s)
- A. Potapov
- Department of Chemical Physics, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - Y. Song
- Department of Chemical Physics, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - T. J. Meade
- Department of Chemistry; Department of Biochemistry, Cell Biology, and Molecular Biology; Neurobiology & Physiology; Department of Radiology, Northwestern University, 2145 Sheridan Road, Evanston, IL 60208, USA
| | - D. Goldfarb
- Department of Chemical Physics, Weizmann Institute of Science, Rehovot, 76100, Israel
| | - A.V. Astashkin
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721-0041, USA
| | - A. Raitsimring
- Department of Chemistry, University of Arizona, Tucson, Arizona 85721-0041, USA
- Corresponding author: Dr. A. Raitsimring, University of Arizona, Department of Chemistry, 1306 E. University Blvd, Tucson, AZ 85721. ; tel (520)621-9968; fax (520)621-8407
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145
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Yang Z, Kise D, Saxena S. An Approach towards the Measurement of Nanometer Range Distances Based on Cu2+ Ions and ESR. J Phys Chem B 2010; 114:6165-74. [DOI: 10.1021/jp911637s] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Zhongyu Yang
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260
| | - Drew Kise
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260
| | - Sunil Saxena
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260
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146
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Sajid M, Jeschke G, Wiebcke M, Godt A. Conformationally Unambiguous Spin Labeling for Distance Measurements. Chemistry 2009; 15:12960-2. [DOI: 10.1002/chem.200902162] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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147
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Abstract
The understanding of structure-dynamics-function relationships in oligonucleotides or oligonucleotide/protein complexes calls for biophysical methods that can resolve the structure and dynamics of such systems on the critical nanometer length scale. A modern electron paramagnetic resonance (EPR) method called pulsed electron-electron double resonance (PELDOR or DEER) has been shown to reliably and precisely provide distances and distance distributions in the range of 1.5-8nm. In addition, recent experiments proved that a PELDOR experiment also contains information on the orientation of labels, enables easy separation of coupling mechanisms and allows for counting the number of monomers in complexes. This chapter briefly summarizes the theory, describes how to perform and analyze such experiments and discusses the limitations.
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148
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Lovett JE, Hoffmann M, Cnossen A, Shutter ATJ, Hogben HJ, Kay CWM, Timmel CR, Anderson HL. Probing Flexibility in Porphyrin-Based Molecular Wires Using Double Electron Electron Resonance. J Am Chem Soc 2009; 131:13852-9. [DOI: 10.1021/ja905796z] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Janet E. Lovett
- Centre for Advanced Electron Spin Resonance, Inorganic Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom, Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, United Kingdom, Deptartment of Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford, OX1 3TA, United Kingdom, Synchrotron Radiation Source, Daresbury Laboratory, Warrington WA4 4AD, United Kingdom, Department of Chemistry,
| | - Markus Hoffmann
- Centre for Advanced Electron Spin Resonance, Inorganic Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom, Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, United Kingdom, Deptartment of Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford, OX1 3TA, United Kingdom, Synchrotron Radiation Source, Daresbury Laboratory, Warrington WA4 4AD, United Kingdom, Department of Chemistry,
| | - Arjen Cnossen
- Centre for Advanced Electron Spin Resonance, Inorganic Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom, Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, United Kingdom, Deptartment of Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford, OX1 3TA, United Kingdom, Synchrotron Radiation Source, Daresbury Laboratory, Warrington WA4 4AD, United Kingdom, Department of Chemistry,
| | - Alexander T. J. Shutter
- Centre for Advanced Electron Spin Resonance, Inorganic Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom, Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, United Kingdom, Deptartment of Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford, OX1 3TA, United Kingdom, Synchrotron Radiation Source, Daresbury Laboratory, Warrington WA4 4AD, United Kingdom, Department of Chemistry,
| | - Hannah J. Hogben
- Centre for Advanced Electron Spin Resonance, Inorganic Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom, Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, United Kingdom, Deptartment of Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford, OX1 3TA, United Kingdom, Synchrotron Radiation Source, Daresbury Laboratory, Warrington WA4 4AD, United Kingdom, Department of Chemistry,
| | - Christopher W. M. Kay
- Centre for Advanced Electron Spin Resonance, Inorganic Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom, Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, United Kingdom, Deptartment of Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford, OX1 3TA, United Kingdom, Synchrotron Radiation Source, Daresbury Laboratory, Warrington WA4 4AD, United Kingdom, Department of Chemistry,
| | - Christiane R. Timmel
- Centre for Advanced Electron Spin Resonance, Inorganic Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom, Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, United Kingdom, Deptartment of Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford, OX1 3TA, United Kingdom, Synchrotron Radiation Source, Daresbury Laboratory, Warrington WA4 4AD, United Kingdom, Department of Chemistry,
| | - Harry L. Anderson
- Centre for Advanced Electron Spin Resonance, Inorganic Chemistry Laboratory, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom, Sir William Dunn School of Pathology, University of Oxford, South Parks Road, Oxford OX1 3RE, United Kingdom, Deptartment of Chemistry, Chemistry Research Laboratory, University of Oxford, Mansfield Road, Oxford, OX1 3TA, United Kingdom, Synchrotron Radiation Source, Daresbury Laboratory, Warrington WA4 4AD, United Kingdom, Department of Chemistry,
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149
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Abstract
AbstractIn order to fulfill their function, membrane transport proteins have to cycle through a number of conformational and/or energetic states. Thus, understanding the role of conformational dynamics seems to be the key for elucidation of the functional mechanism of these proteins. However, membrane proteins in general are often difficult to express heterologously and in sufficient amounts for structural studies. It is especially challenging to trap a stable energy minimum, e.g., for crystallographic analysis. Furthermore, crystallization is often only possible by subjecting the protein to conditions that do not resemble its native environment and crystals can only be snapshots of selected conformational states. Nuclear magnetic resonance (NMR) and electron paramagnetic resonance (EPR) spectroscopy are complementary methods that offer unique possibilities for studying membrane proteins in their natural membrane environment and for investigating functional conformational changes, lipid interactions, substrate-lipid and substrate-protein interactions, oligomerization states and overall dynamics of membrane transporters. Here, we review recent progress in the field including studies from primary and secondary active transporters.
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150
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Ghimire H, McCarrick RM, Budil DE, Lorigan GA. Significantly improved sensitivity of Q-band PELDOR/DEER experiments relative to X-band is observed in measuring the intercoil distance of a leucine zipper motif peptide (GCN4-LZ). Biochemistry 2009; 48:5782-4. [PMID: 19476379 DOI: 10.1021/bi900781u] [Citation(s) in RCA: 62] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Pulsed electron double resonance (PELDOR)/double electron-electron resonance (DEER) spectroscopy is a very powerful structural biology tool in which the dipolar coupling between two unpaired electron spins (site-directed nitroxide spin-labels) is measured. These measurements are typically conducted at X-band (9.4 GHz) microwave excitation using the four-pulse DEER sequence and can often require up to 12 h of signal averaging for biological samples (depending on the spin-label concentration). In this work, we present for the first time a substantial increase in DEER sensitivity obtained by collecting DEER spectra at Q-band (34 GHz), when compared to X-band. The huge boost in sensitivity (factor of 13) demonstrated at Q-band represents a 169-fold decrease in data collection time, reveals a greatly improved frequency spectrum and higher-quality distance data, and significantly increases sample throughput. Thus, the availability of Q-band DEER spectroscopy should have a major impact on structural biology studies using site-directed spin labeling EPR techniques.
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