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Sizun C. Biophysical Reviews' "Meet the Editors Series": a profile of Christina Sizun. Biophys Rev 2023; 15:301-304. [PMID: 37396447 PMCID: PMC10310629 DOI: 10.1007/s12551-023-01071-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/16/2023] [Indexed: 07/04/2023] Open
Abstract
This edition of the continuing "Biophysical Reviews Meet the Editors Series" introduces Dr. Christina Sizun, physical chemist, member of the Biophysical Reviews editorial board and current Treasurer of the International Union for Pure and Applied Biophysics (IUPAB).
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Affiliation(s)
- Christina Sizun
- Institut de Chimie des Substances Naturelles, Centre National de la Recherche Scientifique, Université Paris-Saclay, Gif-sur-Yvette, France
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Caillon L, Lequin O, Khemtémourian L. Evaluation of membrane models and their composition for islet amyloid polypeptide-membrane aggregation. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1828:2091-8. [PMID: 23707907 DOI: 10.1016/j.bbamem.2013.05.014] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2012] [Revised: 04/26/2013] [Accepted: 05/13/2013] [Indexed: 01/01/2023]
Abstract
Human islet amyloid polypeptide (IAPP) forms amyloid fibrils in the pancreatic islets of patients suffering from type 2 diabetes mellitus (T2DM). The formation of IAPP fibrils has been shown to cause membrane damage which most likely is responsible for the death of pancreatic islet β-cells during the pathogenesis of T2DM. Several studies have demonstrated a clear interaction between IAPP and lipid membranes. However the effect of different lipid compositions and of various membrane mimetics (including micelles, bicelles, SUV and LUV) on fibril formation kinetics and fibril morphology has not yet systematically been analysed. Here we report that the interaction of IAPP with various membrane models promoted different processes of fibril formation. Our data reveal that in SDS and DPC micelles, IAPP adopts a stable α-helical structure for several days, suggesting that the micelle models may stabilize monomeric or small oligomeric species of IAPP. In contrast, zwitterionic DMPC/DHPC bicelles and DOPC SUV accelerate the fibril formation compared to zwitterionic DOPC LUV, indicating that the size of the membrane model and its curvature influence the fibrillation process. Negatively charged membranes decrease the lag-time of the fibril formation kinetics while phosphatidylethanolamine and cholesterol have an opposite effect, probably due to the modulation of the physical properties of the membrane and/or due to direct interactions with IAPP within the membrane core. Finally, our results show that the modulation of lipid composition influences not only the growth of fibrils at the membrane surface but also the interactions of β-sheet oligomers with membranes.
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Key Words
- 1,1,1,3,3,3-hexafluoro-2-propanol
- 1,2-dihexanoyl-sn-glycero-3-phosphocholine
- 1,2-dimyristoyl-sn-glycero-3-phosphocholine
- 1,2-dioleoyl-sn-glycero-3-phospho-(1′-rac-glycerol)
- 1,2-dioleoyl-sn-glycero-3-phospho-L-serine
- 1,2-dioleoyl-sn-glycero-3-phosphocholine
- 1,2-dioleoyl-sn-glycero-3-phosphoethanolamine
- 1,2-dipalmitoyl-sn-glycero-3-phosphocholine
- 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine
- Aggregation kinetics
- Amyloid
- CD
- Chol
- DHPC
- DMPC
- DMSO
- DOPC
- DOPE
- DOPG
- DOPS
- DPC
- DPPC
- Fibril morphology
- HFIP
- IAPP
- LUV
- Model membranes (LUV SUV, bicelles, micelles)
- POPC
- Phospholipid
- SDS
- SM
- ThT
- Thioflavin T
- cholesterol
- circular dichroism
- dimethyl sulfoxide
- dodecyl phosphocholine
- human Islet Amyloid Polypeptide
- large unilamellar vesicle
- sodium dodecyl sulphate
- sphingomyelin
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Affiliation(s)
- Lucie Caillon
- UPMC Univ Paris 06, UMR 7203 CNRS-UPMC-ENS, Laboratoire des Biomolécules, 4 place Jussieu, 75005 Paris, France
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Dürr UN, Gildenberg M, Ramamoorthy A. The magic of bicelles lights up membrane protein structure. Chem Rev 2012; 112:6054-74. [PMID: 22920148 PMCID: PMC3497859 DOI: 10.1021/cr300061w] [Citation(s) in RCA: 266] [Impact Index Per Article: 22.2] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2012] [Indexed: 12/12/2022]
Affiliation(s)
| | - Melissa Gildenberg
- Biophysics
and Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109-1055,
United States
| | - Ayyalusamy Ramamoorthy
- Biophysics
and Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109-1055,
United States
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Warschawski DE, Arnold AA, Beaugrand M, Gravel A, Chartrand É, Marcotte I. Choosing membrane mimetics for NMR structural studies of transmembrane proteins. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2011; 1808:1957-74. [DOI: 10.1016/j.bbamem.2011.03.016] [Citation(s) in RCA: 239] [Impact Index Per Article: 18.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2010] [Revised: 03/28/2011] [Accepted: 03/29/2011] [Indexed: 12/11/2022]
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Diller A, Loudet C, Aussenac F, Raffard G, Fournier S, Laguerre M, Grélard A, Opella SJ, Marassi FM, Dufourc EJ. Bicelles: A natural 'molecular goniometer' for structural, dynamical and topological studies of molecules in membranes. Biochimie 2009; 91:744-51. [PMID: 19248817 PMCID: PMC2899883 DOI: 10.1016/j.biochi.2009.02.003] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2008] [Accepted: 02/13/2009] [Indexed: 10/21/2022]
Abstract
Major biological processes occur at the biological membrane. One of the great challenges is to understand the function of chemical or biological molecules inside the membrane; as well of those involved in membrane trafficking. This requires obtaining a complete picture of the in situ structure and dynamics as well as the topology and orientation of these molecules in the membrane lipid bilayer. These led to the creation of several innovative models of biological membranes in order to investigate the structure and dynamics of amphiphilic molecules, as well as integral membrane proteins having single or multiple transmembrane segments. Because the determination of the structure, dynamics and topology of molecules in membranes requires a macroscopic alignment of the system, a new membrane model called 'bicelles' that represents a crossover between lipid vesicles and classical micelles has become very popular due to its property of spontaneous self-orientation in magnetic fields. In addition, crucial factors involved in mimicking natural membranes, such as sample hydration, pH and salinity limits, are easy to control in bicelle systems. Bicelles are composed of mixtures of long chain (14-18 carbons) and short chain phospholipids (6-8 carbons) hydrated up to 98% with buffers and may adopt various morphologies depending on lipid composition, temperature and hydration. We have been developing bicelle systems under the form of nano-discs made of lipids with saturated or biphenyl-containing fatty acyl chains. Depending on the lipid nature, these membranous nano-discs may be macroscopically oriented with their normal perpendicular or parallel to the magnetic field, providing a natural 'molecular goniometer' for structural and topological studies, especially in the field of NMR. Bicelles can also be spun at the magic angle and lead to the 3D structural determination of molecules in membranes.
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Affiliation(s)
- Anna Diller
- CBMN UMR 5248, CNRS, Université Bordeaux, ENITAB, IECB, 2, rue Robert Escarpit, 33607 Pessac, France
| | - Cécile Loudet
- The Burnham Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037, USA
| | | | - Gérard Raffard
- RMSB UMR 5536, CNRS, Université Bordeaux, Bordeaux, France
| | - Sylvie Fournier
- CBMN UMR 5248, CNRS, Université Bordeaux, ENITAB, IECB, 2, rue Robert Escarpit, 33607 Pessac, France
| | - Michel Laguerre
- CBMN UMR 5248, CNRS, Université Bordeaux, ENITAB, IECB, 2, rue Robert Escarpit, 33607 Pessac, France
| | - Axelle Grélard
- CBMN UMR 5248, CNRS, Université Bordeaux, ENITAB, IECB, 2, rue Robert Escarpit, 33607 Pessac, France
| | - Stanley J. Opella
- Department of Chemistry and Biochemistry, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0307, USA
| | | | - Erick J. Dufourc
- CBMN UMR 5248, CNRS, Université Bordeaux, ENITAB, IECB, 2, rue Robert Escarpit, 33607 Pessac, France
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Loudet C, Manet S, Gineste S, Oda R, Achard MF, Dufourc EJ. Biphenyl bicelle disks align perpendicular to magnetic fields on large temperature scales: a study combining synthesis, solid-state NMR, TEM, and SAXS. Biophys J 2007; 92:3949-59. [PMID: 17307824 PMCID: PMC1868983 DOI: 10.1529/biophysj.106.097758] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
A phosphatidylcholine lipid (PC) containing a biphenyl group in one of its acyl chains (1-tetradecanoyl-2-(4-(4-biphenyl)butanoyl)-sn-glycero-3-PC, TBBPC) was successfully synthesized with high yield. Water mixtures of TBBPC with a short-chain C(6) lipid, dicaproyl-PC (DCPC), lead to bicelle systems formation. Freeze-fracture electron microscopy evidenced the presence of flat bilayered disks of 800 A diameter for adequate composition, hydration, and temperature conditions. Because of the presence of the biphenyl group, which confers to the molecule a positive magnetic anisotropy Delta chi, the disks align with their normal, n, parallel to the magnetic field B(0), as directly detected by (31)P, (14)N, (2)H solid-state NMR and also using small-angle x-ray scattering after annealing in the field. Temperature-composition and temperature-hydration diagrams were established. Domains where disks of TBBPC/DCPC align with their normal parallel to the field were compared to chain-saturated lipid bicelles made of DMPC(dimyristoylPC)/DCPC, which orient with their normal perpendicular to B(0). TBBPC/DCPC bicelles exist on a narrow range of long- versus short-chain lipid ratios (3%) but over a large temperature span around room temperature (10-75 degrees C), whereas DMPC/DCPC bicelles exhibit the reverse situation, i.e., large compositional range (22%) and narrow temperature span (25-45 degrees C). The two types of bicelles present orienting properties up to 95% dilution but with the peculiarity that water trapped in biphenyl bicelles exhibits ordering properties twice as large as those observed in the saturated-chains analog, which offers very interesting properties for structural studies on hydrophilic or hydrophobic embedded biomolecules.
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Affiliation(s)
- Cécile Loudet
- UMR 5248 CBMN, CNRS-Université Bordeaux 1-ENITAB, Institut Européen de Chimie et Biologie, Pessac, France
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Renault M, Réat V, Sugawara M, Demange P, Phez É, Teissie J, Piotto M, Milon A. Giant vesicles as an efficient intermediate for 2H NMR analyses of proteoliposomes in water suspension and in oriented lipid bilayers. CR CHIM 2006. [DOI: 10.1016/j.crci.2005.06.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Khemtémourian L, Lavielle S, Bathany K, Schmitter JM, Dufourc EJ. Revisited and large-scale synthesis and purification of the mutated and wild type neu/erbB-2 membrane-spanning segment. J Pept Sci 2006; 12:361-8. [PMID: 16285025 DOI: 10.1002/psc.735] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Solid-phase syntheses of the hydrophobic peptides Neu(TM35) ((1)EQRASPVTFIIATVVGVLLFLILVVVVGILIKRRR(35)) and Neu*(TM35) ((1)EQRASPVTFIIATVEGVLLFLILVVVVGILIKRRR(35)), corresponding to the native and mutated (V15E) transmembrane domain of the neu/erbB-2 tyrosine kinase receptor, respectively, were accomplished using Fmoc chemistry. The use of a new resin and cleavage and purification conditions led to large increases in yields and peptide purity. Two (15)N-labelled versions of both wild type and mutated peptides were also synthesized. Approximately 20-40 mg of peptide was obtained using a small-scale synthesis, whereas ca 100 mg of pure peptide was collected on a medium scale. Peptide purity, as monitored by HPLC and mass spectrometry, ranged from 95 to 98% for the six peptides synthesized. Secondary structure as determined by UV circular dichroism (CD) in trifluoroethanol (TFE) showed ca 74% alpha-helical content for the native peptide and ca 63% for that bearing the mutation. Secondary structure of Neu(TM35) was retained in DMPC (dimyristoylphosphatidylcholine)/DCPC (dicaproylphosphatidylcholine) membrane bicelles, and evidences for dimers/oligomers in the lipid bilayer were found.
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Affiliation(s)
- Lucie Khemtémourian
- UMR 5144 MOBIOS, CNRS-University Bordeaux 1, IECB, 2 rue Robert Escarpit, 33607 Bordeaux-Pessac, France
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Triba MN, Zoonens M, Popot JL, Devaux PF, Warschawski DE. Reconstitution and alignment by a magnetic field of a β-barrel membrane protein in bicelles. EUROPEAN BIOPHYSICS JOURNAL: EBJ 2005; 35:268-75. [PMID: 16187128 DOI: 10.1007/s00249-005-0014-x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2005] [Revised: 08/12/2005] [Accepted: 08/25/2005] [Indexed: 10/25/2022]
Abstract
A protocol is described for the reconstitution of a transmembrane beta-barrel protein domain, tOmpA, into lipid bicelles. tOmpA is the largest protein to be reconstituted in bicelles to date. Its insertion does not prevent bicelles from orienting with their plane either parallel or perpendicular to the magnetic field, depending on the absence or presence of paramagnetic ions. In the latter case, tOmpA is shown to align with the axis of the beta-barrel parallel to the magnetic field, i.e. perpendicular to the plane of the bilayer, an orientation conforming to that in natural membranes and favourable to structural studies by solid-state NMR. Reconstitution into bicelles may offer an interesting approach for structural studies of membrane proteins in a medium resembling a biological membrane, using either NMR or other biophysical techniques. Our data suggest that alignment in the magnetic field of membrane proteins included into bicelles may be facilitated if the protein is folded as a beta-barrel structure.
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Affiliation(s)
- Mohamed N Triba
- Unité Mixte de Recherche No 7099, Institut de Biologie Physico-Chimique, CNRS - Université Paris 7-Denis Diderot, 13 rue Pierre et Marie Curie, 75005 Paris, France
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Aussenac F, Lavigne B, Dufourc EJ. Toward bicelle stability with ether-linked phospholipids: temperature, composition, and hydration diagrams by 2H and 31P solid-state NMR. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2005; 21:7129-35. [PMID: 16042433 DOI: 10.1021/la050243a] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Phosphorus and deuterium wide line NMR was used to determine diagrams of binary mixtures of 1,2-di-O-tetradecyl-sn-glycero-3-phosphocholine (DIOMPC) and 1,2-di-O-hexyl-sn-glycero-3-phosphocholine (DIOHPC) ether-phospholipids. By varying the hydration, h, the temperature, T, and the mole fraction, X, of long-chain ether-phospholipids, we delineated the conditions for which such systems are oriented by the magnetic field, in the presence of 100 mM KCl. The 3D domain is found for X = 62-90%, T = 27-50 degrees C, and h = 70-98%. At 80% hydration, the domain shape (X = 70-90% and T = 27-42 degrees C) is close to that already observed for ester-phospholipids mixtures (Raffard, G.; Steinbruckner, S.; Arnold, A.; Davis, J. H.; Dufourc, E. J. Langmuir 2000, 16, 7655-7662) where disc-shaped bicelles of 300-600 A have been found by electron microscopy (Arnold, A.; Labrot, T.; Oda, R.; Dufourc, E. J. Biophys. J. 2002, 83, 2667-2680). Systems made of ether-linked lipids are much more stable on time and acidic conditions than those made of ester lipids. Assuming that the disc-shaped species are also found with ether lipids, their diameter as determined from integration of phosphorus NMR lines ranges from 240 to 440 A +/- 10%; it is generally independent of hydration and temperature but decreases with decreasing long-chain lipid content, X. The structure and the dynamics of water in the DIOMPC-DIOHPC were characterized by (2)H NMR. Water exchanges between the membrane surface where it is bound and a bulk isotropic pool lead to an average ordered state for temperatures in the bicelle region and above, thus offering a larger thermal span for structural studies of dissolved molecules.
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Affiliation(s)
- Fabien Aussenac
- Bruker Biospin, Laboratoire d'applications, Wissembourg, France, and UMR5144 CNRS-UBx1, Institut Européen de Chimie et Biologie, Pessac, France
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Loudet C, Khemtémourian L, Aussenac F, Gineste S, Achard MF, Dufourc EJ. Bicelle membranes and their use for hydrophobic peptide studies by circular dichroism and solid state NMR. Biochim Biophys Acta Gen Subj 2005; 1724:315-23. [PMID: 15961233 DOI: 10.1016/j.bbagen.2005.04.026] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2005] [Revised: 04/23/2005] [Accepted: 04/26/2005] [Indexed: 10/25/2022]
Abstract
Mixtures of dicaproyl- (DC), dimyristoyl- (DM) and 1-tetradecanoyl-2-biphenylbutanoyl-(TBB) phosphatidylcholine (PC) in water produce bicelle membranes that are oriented by magnetic fields. DMPC/DCPC systems orient such that their membrane plane is parallel to the magnetic field, whereas for TBBPC/DCPC, the plane is perpendicular to the field. Partial temperature-composition-hydration diagrams are established using solid-state 31P-NMR. DMPC/DCPC bicelles exist on a large range of composition but on a narrow temperature domain (25-45 degrees C). At converse, TBBPC/DCPC form bicelles on a narrow compositional range but over a large temperature span (10-70 degrees C). The TBBPC/DCPC bicelles are shown to be a very powerful potential tool to study the orientation of hydrophobic helices in membranes using wide line 15N-NMR. The DMPC/DCPC system that undergoes a micelle-to-bicelle transition on going from 10 degrees C to 40 degrees C may be used with circular dichroism to study the state of association of hydrophobic helices within the membrane. Results suggest that the transmembrane fragment of the neu/erbB-2 receptor is monomeric in micellar medium and dimeric/multimeric in bicelle membranes.
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Affiliation(s)
- Cécile Loudet
- UMR5144 MOBIOS, CNRS-UBx1, Institut Européen de Chimie et Biologie, 33607 Pessac, France
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Harroun TA, Koslowsky M, Nieh MP, de Lannoy CF, Raghunathan VA, Katsaras J. Comprehensive examination of mesophases formed by DMPC and DHPC mixtures. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2005; 21:5356-61. [PMID: 15924461 DOI: 10.1021/la050018t] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
Mixtures of long- and short-chain phospholipids, specifically 14:0 and 6:0 phosphatidylcholines (DMPC and DHPC), have been used successfully in NMR studies as magnetically alignable substrates for membrane-associated proteins. However, recent publications have shown that the phase behavior of these mixtures is much more complex than originally thought. Using polarized light microscopy and small-angle neutron scattering, phase diagrams of DMPC/DHPC mixtures at molar ratios of 2, 3.2, and 5 have been determined. Generally, at temperatures below the main-chain melting transition of DMPC (T(M) = 23 degrees C), an isotropic phase of disk-like micelles is found. At high temperatures (T > 50 degrees C), a lamellar phase consisting of either multilamellar vesicles (MLV) or extended lamellae is formed, which at low lipid concentrations (e.g., MLV) coexists with an excess of water. At intermediate temperatures and lipid concentrations, a chiral nematic phase made up of worm-like micelles was observed.
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Affiliation(s)
- Thad A Harroun
- Steacie Institute for Molecular Sciences, National Research Council, Chalk River, Ontario K0J 1J0, Canada
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De Angelis AA, Nevzorov AA, Park SH, Howell SC, Mrse AA, Opella SJ. High-resolution NMR spectroscopy of membrane proteins in aligned bicelles. J Am Chem Soc 2005; 126:15340-1. [PMID: 15563135 DOI: 10.1021/ja045631y] [Citation(s) in RCA: 93] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
High-resolution solid-state NMR spectra can be obtained from uniformly (15)N-labeled membrane proteins in magnetically aligned bicelles. Fast uniaxial diffusion about the axis of the bilayer normal results in single-line spectra that contain the orientational information necessary for protein structure determination.
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Affiliation(s)
- Anna A De Angelis
- Department of Chemistry and Biochemistry, University of California San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0307, USA
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Bechinger B, Aisenbrey C, Bertani P. The alignment, structure and dynamics of membrane-associated polypeptides by solid-state NMR spectroscopy. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2005; 1666:190-204. [PMID: 15519315 DOI: 10.1016/j.bbamem.2004.08.008] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/30/2004] [Accepted: 08/06/2004] [Indexed: 10/26/2022]
Abstract
Solid-state NMR spectroscopy is being developed at a fast pace for the structural investigation of immobilized and non-crystalline biomolecules. These include proteins and peptides associated with phospholipid bilayers. In contrast to solution NMR spectroscopy, where complete or almost complete averaging leads to isotropic values, the anisotropic character of nuclear interactions is apparent in solid-state NMR spectra. In static samples the orientation dependence of chemical shift, dipolar or quadrupolar interactions, therefore, provides angular constraints when the polypeptides have been reconstituted into oriented membranes. Furthermore, solid-state NMR spectroscopy of aligned samples offers distinct advantages in allowing access to dynamic processes such as topological equilibria or rotational diffusion in membrane environments. Alternatively, magic angle sample spinning (MAS) results in highly resolved NMR spectra, provided that the sample is sufficiently homogenous. MAS spinning solid-state NMR spectra allow to measure distances and dihedral angles with high accuracy. The technique has recently been developed to selectively establish through-space and through-bond correlations between nuclei, similar to the approaches well-established in solution-NMR spectroscopy.
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Affiliation(s)
- Burkhard Bechinger
- Faculté de chimie, Institut le Bel, 4, rue Blaise Pascal, 67000 Strasbourg, France.
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