Nuclear magnetic resonance (NMR) structure calculations of the ?-helical integral membrane proteins DsbB, GlpG, and halorhodopsin show that distance restraints from paramagnetic relaxation enhancement (PRE) can provide sufficient structural information to determine their structure with an accuracy of about 1.5*Å in the absence of other long-range conformational restraints. Our systematic study with simulated NMR data shows that about one spin label per transmembrane helix is necessary for obtaining enough PRE distance restraints to exclude wrong topologies, such as pseudo mirror images, if only limited other NMR restraints are available. Consequently, an experimentally realistic amount of PRE data enables ?-helical membrane protein structure determinations that would not be feasible with the very limited amount of conventional NOESY data normally available for these systems. These findings are in line with our recent first de novo NMR structure determination of a heptahelical integral membrane protein, proteorhodopsin, that relied extensively on PRE data. Highlights
? NMR structures of ?-helical membrane proteins with ~1.5*Å accuracy from PREs ? Structure calculations are insensitive to error margins for PRE distance limits ? About one spin label per transmembrane helix required to define correct topology ? Sufficient PRE data exclude topological mirror images
[Question from NMRWiki Q&A forum] why we are seeing negative PREs in paramagnetic relaxation enhancement experiment?
why we are seeing negative PREs in paramagnetic relaxation enhancement experiment?
Hi NMR Wiki users,
I'm using two point method(Marius Clore and Junji Iwahara methods) to measure the PREs, but in my experiment I observed so many negative PREs. Is there any chance to use these negative PREs data in structure calculation.How can I get all positive PREs,otherwise I lose half of the data in my calculations.
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12-11-2012 07:30 PM
Paramagnetic relaxation enhancement to improve sensitivity of fast NMR methods: application to intrinsically disordered proteins
Paramagnetic relaxation enhancement to improve sensitivity of fast NMR methods: application to intrinsically disordered proteins
Abstract We report enhanced sensitivity NMR measurements of intrinsically disordered proteins in the presence of paramagnetic relaxation enhancement (PRE) agents such as Ni2+-chelated DO2A. In proton-detected 1H-15N SOFAST-HMQC and carbon-detected (H-flip)13CO-15N experiments, faster longitudinal relaxation enables the usage of even shorter interscan delays. This results in higher NMR signal intensities per units of experimental time, without adverse line...
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10-21-2011 10:04 PM
Solid-State NMR of a Large Membrane Protein by Paramagnetic Relaxation Enhancement.
Solid-State NMR of a Large Membrane Protein by Paramagnetic Relaxation Enhancement.
Solid-State NMR of a Large Membrane Protein by Paramagnetic Relaxation Enhancement.
J Phys Chem Lett. 2011 Jul 21;2(14):1836-1841
Authors: Tang M, Berthold DA, Rienstra CM
Membrane proteins play an important role in many biological functions. Solid-state NMR spectroscopy is uniquely suited for studying structure and dynamics of membrane proteins in a membranous environment. The major challenge to obtain high quality solid-state NMR spectra of membrane proteins is...
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08-16-2011 01:19 PM
[NMR paper] Determination of protein rotational correlation time from NMR relaxation data at vari
Determination of protein rotational correlation time from NMR relaxation data at various solvent viscosities.
Related Articles Determination of protein rotational correlation time from NMR relaxation data at various solvent viscosities.
J Biomol NMR. 2004 Dec;30(4):431-42
Authors: Korchuganov DS, Gagnidze IE, Tkach EN, Schulga AA, Kirpichnikov MP, Arseniev AS
An accurate determination of the overall rotation of a protein plays a crucial role in the investigation of its internal motions by NMR. In the present work, an innovative approach to the...
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11-24-2010 10:03 PM
[Question from NMRWiki Q&A forum] Relaxation editing vr paramagnetic relaxation enhancement experiments - 13C CP-MAS NM
Relaxation editing vr paramagnetic relaxation enhancement experiments - 13C CP-MAS NMR
I am a beginner in NMR spectroscopy and I would like to learn more about relaxation editing experiments vs PRE. A colleague of mine is doing the 13C CP-MAS NMR experim. and he using cellulose II powder, regenerated cellulose and milled reg cellulose. We are interested in C4 resonance of cellulose II, good resolved resonance, to better understand the supramolecular structure of cellulose II. As experiments: long relaxation experiments - PRE with aqueous CuSO4 solution of certain concentration, does the...
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10-15-2010 05:16 PM
Solid-state NMR paramagnetic relaxation enhancement immersion depth studies in phosph
Solid-state NMR paramagnetic relaxation enhancement immersion depth studies in phospholipid bilayers.
http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--linkinghub.elsevier.com-ihub-images-PubMedLink.gif Related Articles Solid-state NMR paramagnetic relaxation enhancement immersion depth studies in phospholipid bilayers.
J Magn Reson. 2010 Aug 24;
Authors: Chu S, Maltsev S, Emwas AH, Lorigan GA
A new approach for determining the membrane immersion depth of a spin-labeled probe has been developed using paramagnetic relaxation enhancement (PRE)...
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09-22-2010 05:27 AM
[Question from NMRWiki Q&A forum] Does anyone know something about paramagnetic relaxation enhancement (PRE)?
Does anyone know something about paramagnetic relaxation enhancement (PRE)?
Does anyone know something about paramagnetic relaxation enhancement (PRE)? i would like to try this method on my cellulose materials. What info can you take out of it? Thank you very much.
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09-08-2010 12:08 AM
[NMR paper] Relaxation data in NMR structure determination: model calculations for the lysozyme-G
Relaxation data in NMR structure determination: model calculations for the lysozyme-Gd3+ complex.
Related Articles Relaxation data in NMR structure determination: model calculations for the lysozyme-Gd3+ complex.
Proteins. 1991;10(2):117-29
Authors: Sutcliffe MJ, Dobson CM
The effect of including paramagnetic relaxation data as additional restraints in the determination of protein tertiary structures from NMR data has been explored by a systematic series of model calculations. The system used for testing the method was the 2.0 A resolution...