Related ArticlesThe origin of differences in the physical properties of the equilibrium forms of cytochrome b5 revealed through high-resolution NMR structures and backbone dynamic analyses.
On the basis of a comparison of high-resolution solution structures calculated for both equilibrium forms of rat ferrocytochrome b5, differences in reduction potential and thermodyanmic stability have been characterized in terms of significant structural and dynamic differences between the two forms. The dominant difference between A and B conformations has long been known to be due to a 180 degrees rotation of the heme in the binding pocket about an axis defined by the alpha- and gamma-meso carbons, however, the B form has not been structurally characterized until now. The most significant differences observed between the two forms were the presence of a hydrogen bond between the 7-propionate and the S64 amide in the A form but not the B form and surprisingly a displacement of the heme out of the binding pocket by 0.9 A in the B form relative to the A form. The magnitude of other factors which could contribute to the known difference in reduction potentials in the bovine protein [Walker, F. A., Emrick, D., Rivera, J. E., Hanquet, B. J., and Buttlaire, D. H. (1988) J. Am. Chem. Soc. 110, 6234-6240], such as differences in the orientation of the axial imidazoles and differences in hydrogen bond strength to the imidazoles, have been evaluated. The dominant effector of the reduction potential would appear to be the lack of the hydrogen bond to the S64 amide in the B form which frees up the propionate to charge stabilize the iron in the oxidized state and thus lower the reduction potential of the B form. The structure we report for the A form, based on heteronuclear NMR restraints, involving a total of 1288 restraints strongly resembles both the X-ray crystal structure of the bovine protein and a recently reported structure for the A form of the rat protein based on homonuclear data alone [Banci, L., Bertini, I., Ferroni, F., and Rosato, A. (1997) Eur. J. Biochem. 249, 270-279]. The rmsd for the backbone atoms of the A form is 0.54 A (0.92 A for all non-hydrogens). The rmsd for the backbone of the B form is 0.51 A (0. 90 A for all non-hydrogen atoms). An analysis of backbone dynamics based on a model-free analysis of 15N relaxation data, which incorporated axially symmetric diffusion tensor modeling of the cytochrome, indicates that the protein is more rigid in the reduced state relative to the oxidized state, based on a comparison with order parameters reported for the bovine protein in the oxidized state [Kelly, G. P., Muskett, F. W., and Whitford, D. (1997) Eur. J. Biochem. 245, 349-354].
[Question from NMRWiki Q&A forum] exporting part of data to excel, origin
exporting part of data to excel, origin
Hi,i'm new in TopSpin and i am blocked by a simple (i thinks) problem.I have a 1D specrtrum and i would like to export it to excel or origin but my spectrum have a small S/N so there is to much point --> i want this spectrum with less point but without smoothing (if it's possible).In other word, how can i do to tell TopSpin "get the spectrum but only every 10 points (or X points)" ?
Thank you in advance for those who will have the kindness to answer.
Check if somebody has answered this question on NMRWiki QA forum
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06-29-2011 04:51 PM
[NMR paper] NMR analysis of the transient complex between membrane photosystem I and soluble cyto
NMR analysis of the transient complex between membrane photosystem I and soluble cytochrome c6.
Related Articles NMR analysis of the transient complex between membrane photosystem I and soluble cytochrome c6.
J Biol Chem. 2005 Mar 4;280(9):7925-31
Authors: Díaz-Moreno I, Díaz-Quintana A, Molina-Heredia FP, Nieto PM, Hansson O, De la Rosa MA, Karlsson BG
A structural analysis of the surface areas of cytochrome c(6), responsible for the transient interaction with photosystem I, was performed by NMR transverse relaxation-optimized spectroscopy....
nmrlearner
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11-24-2010 10:03 PM
[NMR paper] An NMR study of the origin of dioxygen-induced spin-lattice relaxation enhancement an
An NMR study of the origin of dioxygen-induced spin-lattice relaxation enhancement and chemical shift perturbation.
Related Articles An NMR study of the origin of dioxygen-induced spin-lattice relaxation enhancement and chemical shift perturbation.
J Magn Reson. 2004 Dec;171(2):225-32
Authors: Prosser RS, Luchette PA
Due to its depth-dependent solubility, oxygen exerts paramagnetic effects which become progressively greater toward the hydrophobic interior of micelles, and lipid bilayer membranes. This paramagnetic gradient, which is manifested...
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11-24-2010 10:03 PM
Ligands Turning Around in the Midst of Protein Conformers:the Origin of Ligand-Protei
Ligands Turning Around in the Midst of Protein Conformers:the Origin of Ligand-Protein Mating. A NMR View.
Related Articles Ligands Turning Around in the Midst of Protein Conformers:the Origin of Ligand-Protein Mating. A NMR View.
Curr Top Med Chem. 2010 Nov 12;
Authors: Pertinhez TA, Spisni A
Protein-ligand binding is a puzzling process. Many theories have been devised since the pioneering key-and-lock hypothesis based on the idea that both the protein and the ligand have a rigid single conformation. Indeed, molecular motion is the essence of the...
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10-15-2010 02:01 AM
[NMR paper] X-ray and NMR structure of Bet v 1, the origin of birch pollen allergy.
X-ray and NMR structure of Bet v 1, the origin of birch pollen allergy.
Related Articles X-ray and NMR structure of Bet v 1, the origin of birch pollen allergy.
Nat Struct Biol. 1996 Dec;3(12):1040-5
Authors: Gajhede M, Osmark P, Poulsen FM, Ipsen H, Larsen JN, Joost van Neerven RJ, Schou C, Løwenstein H, Spangfort MD
The three-dimensional structure of the major birch pollen allergen, the 17,500 M(r) acidic protein Bet v 1 (from the birch, Betula verrucosa), is presented as determined both in the crystalline state by X-ray diffraction and in...
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08-22-2010 02:20 PM
[NMR paper] An 1H NMR determination of the three-dimensional structures of mirror-image forms of
An 1H NMR determination of the three-dimensional structures of mirror-image forms of a Leu-5 variant of the trypsin inhibitor from Ecballium elaterium (EETI-II).
http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--www3.interscience.wiley.com-aboutus-images-wiley_interscience_pubmed_logo_FREE_120x27.gif http://www.ncbi.nlm.nih.gov/corehtml/query/egifs/http:--www.pubmedcentral.nih.gov-corehtml-pmc-pmcgifs-pubmed-pmc.gif Related Articles An 1H NMR determination of the three-dimensional structures of mirror-image forms of a Leu-5 variant of the trypsin inhibitor from Ecballium...
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08-22-2010 03:33 AM
[NMR paper] Solid-state 13C and 15N NMR study of the low pH forms of bacteriorhodopsin.
Solid-state 13C and 15N NMR study of the low pH forms of bacteriorhodopsin.
Related Articles Solid-state 13C and 15N NMR study of the low pH forms of bacteriorhodopsin.
Biochemistry. 1990 Jul 24;29(29):6873-83
Authors: de Groot HJ, Smith SO, Courtin J, van den Berg E, Winkel C, Lugtenburg J, Griffin RG, Herzfeld J
The visible absorption of bacteriorhodopsin (bR) is highly sensitive to pH, the maximum shifting from 568 nm (pH 7) to approximately 600 nm (pH 2) and back to 565 nm (pH 0) as the pH is decreased further with HCl. Blue membrane...
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08-21-2010 11:04 PM
How to import NMR data to Origin software
Hi!
I have a little problem, I can't import NMR data (Bruker Avans 600MHz) to Origin 8.0 or 6.0 version. I am affraid that Bruker changed file format, I was able to do this with files from old Bruker 300MHz. Anybody know how to resolve it? Thanks for help!!
Fr