Solid-state (2)h NMR shows equivalence of dehydration and osmotic pressures in lipid membrane deformation.
Biophys J. 2011 Jan 5;100(1):98-107
Authors: Mallikarjunaiah KJ, Leftin A, Kinnun JJ, Justice MJ, Rogozea AL, Petrache HI, Brown MF
Lipid bilayers represent a fascinating class of biomaterials whose properties are altered by changes in pressure or temperature. Functions of cellular membranes can be affected by nonspecific lipid-protein interactions that depend on bilayer material properties. Here we address the changes in lipid bilayer structure induced by external pressure. Solid-state (2)H NMR spectroscopy of phospholipid bilayers under osmotic stress allows structural fluctuations and deformation of membranes to be investigated. We highlight the results from NMR experiments utilizing pressure-based force techniques that control membrane structure and tension. Our (2)H NMR results using both dehydration pressure (low water activity) and osmotic pressure (poly(ethylene glycol) as osmolyte) show that the segmental order parameters (S(CD)) of DMPC approach very large values of ?0.35 in the liquid-crystalline state. The two stresses are thermodynamically equivalent, because the change in chemical potential when transferring water from the interlamellar space to the bulk water phase corresponds to the induced pressure. This theoretical equivalence is experimentally revealed by considering the solid-state (2)H NMR spectrometer as a virtual osmometer. Moreover, we extend this approach to include the correspondence between osmotic pressure and hydrostatic pressure. Our results establish the magnitude of the pressures that lead to significant bilayer deformation including changes in area per lipid and volumetric bilayer thickness. We find that appreciable bilayer structural changes occur with osmotic pressures in the range of 10-100 atm or lower. This research demonstrates the applicability of solid-state (2)H NMR spectroscopy together with bilayer stress techniques for investigating the mechanism of pressure sensitivity of membrane proteins.
Multidimensional oriented solid-state NMR experiments enable the sequential assignment of uniformly 15N labeled integral membrane proteins in magnetically aligned lipid bilayers
Multidimensional oriented solid-state NMR experiments enable the sequential assignment of uniformly 15N labeled integral membrane proteins in magnetically aligned lipid bilayers
Abstract Oriented solid-state NMR is the most direct methodology to obtain the orientation of membrane proteins with respect to the lipid bilayer. The method consists of measuring 1H-15N dipolar couplings (DC) and 15N anisotropic chemical shifts (CSA) for membrane proteins that are uniformly aligned with respect to the membrane bilayer. A significant advantage of this approach is that tilt and azimuthal...
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10-10-2011 06:27 AM
Molecular Dynamics of Proteorhodopsin in Lipid Bilayers by Solid-State NMR.
Molecular Dynamics of Proteorhodopsin in Lipid Bilayers by Solid-State NMR.
Molecular Dynamics of Proteorhodopsin in Lipid Bilayers by Solid-State NMR.
J Am Chem Soc. 2011 Mar 14;
Authors: Yang J, Aslimovska L, Glaubitz C
Environmental factors such as temperature, hydration, and lipid bilayer properties are tightly coupled to the dynamics of membrane proteins. So far, site-resolved data visualizing the protein's response to alterations in these factors are rare, and conclusions had to be drawn from dynamic data averaged over the whole protein...
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03-16-2011 04:15 PM
Molecular Dynamics of Proteorhodopsin in Lipid Bilayers by Solid-State NMR
Molecular Dynamics of Proteorhodopsin in Lipid Bilayers by Solid-State NMR
Jun Yang, Lubica Aslimovska and Clemens Glaubitz
http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/jacsat/0/jacsat.ahead-of-print/ja109766n/aop/images/medium/ja-2010-09766n_0011.gif
Journal of the American Chemical Society
DOI: 10.1021/ja109766n
http://feeds.feedburner.com/~ff/acs/jacsat?d=yIl2AUoC8zA
http://feeds.feedburner.com/~r/acs/jacsat/~4/VmNlca5pCIw
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03-15-2011 05:56 AM
Long-Term-Stable Ether-Lipid vs Conventional Ester-Lipid Bicelles in Oriented Solid-State NMR: Altered Structural Information in Studies of Antimicrobial Peptides.
Long-Term-Stable Ether-Lipid vs Conventional Ester-Lipid Bicelles in Oriented Solid-State NMR: Altered Structural Information in Studies of Antimicrobial Peptides.
Long-Term-Stable Ether-Lipid vs Conventional Ester-Lipid Bicelles in Oriented Solid-State NMR: Altered Structural Information in Studies of Antimicrobial Peptides.
J Phys Chem B. 2011 Feb 10;
Authors: Bertelsen K, Vad B, Nielsen EH, Hansen SK, Skrydstrup T, Otzen DE, Vosegaard T, Nielsen NC
Recently, ether lipids have been introduced as long-term stable alternatives to the more natural,...
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02-12-2011 05:26 PM
[NMR paper] How to prepare membrane proteins for solid-state NMR: A case study on the alpha-helical integral membrane protein diacylglycerol kinase from E. coli.
How to prepare membrane proteins for solid-state NMR: A case study on the alpha-helical integral membrane protein diacylglycerol kinase from E. coli.
Related Articles How to prepare membrane proteins for solid-state NMR: A case study on the alpha-helical integral membrane protein diacylglycerol kinase from E. coli.
Chembiochem. 2005 Sep;6(9):1693-700
Authors: Lorch M, Faham S, Kaiser C, Weber I, Mason AJ, Bowie JU, Glaubitz C
Several studies have demonstrated that it is viable to use microcrystalline preparations of water-soluble proteins as...
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12-01-2010 06:56 PM
[NMR paper] Lipid modifications of a Ras peptide exhibit altered packing and mobility versus host membrane as detected by 2H solid-state NMR.
Lipid modifications of a Ras peptide exhibit altered packing and mobility versus host membrane as detected by 2H solid-state NMR.
Related Articles Lipid modifications of a Ras peptide exhibit altered packing and mobility versus host membrane as detected by 2H solid-state NMR.
J Am Chem Soc. 2005 Sep 7;127(35):12263-72
Authors: Vogel A, Katzka CP, Waldmann H, Arnold K, Brown MF, Huster D
The human N-ras protein binds to cellular membranes by insertion of two covalently bound posttranslational lipid modifications, which is crucial for its...
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12-01-2010 06:56 PM
[NMR paper] Anomalous diffusion in a gel-fluid lipid environment: a combined solid-state NMR and
Anomalous diffusion in a gel-fluid lipid environment: a combined solid-state NMR and obstructed random-walk perspective.
Related Articles Anomalous diffusion in a gel-fluid lipid environment: a combined solid-state NMR and obstructed random-walk perspective.
Biophys J. 2004 Oct;87(4):2456-69
Authors: Arnold A, Paris M, Auger M
Lateral diffusion is an essential process for the functioning of biological membranes. Solid-state nuclear magnetic resonance (NMR) is, a priori, a well-suited technique to study lateral diffusion within a heterogeneous...
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11-24-2010 10:01 PM
[NMR paper] Solid-state NMR studies of the membrane-bound closed state of the colicin E1 channel
Solid-state NMR studies of the membrane-bound closed state of the colicin E1 channel domain in lipid bilayers.
Related Articles Solid-state NMR studies of the membrane-bound closed state of the colicin E1 channel domain in lipid bilayers.
Protein Sci. 1998 Feb;7(2):342-8
Authors: Kim Y, Valentine K, Opella SJ, Schendel SL, Cramer WA
The colicin E1 channel polypeptide was shown to be organized anisotropically in membranes by solid-state NMR analysis of samples of uniformly 15N-labeled protein in oriented planar phospholipid bilayers. The 190...