Abstract Structural knowledge about proteins is mainly derived from values of observables, measurable in NMR spectroscopic or X-ray diffraction experiments, i.e. absorbed or scattered intensities, through theoretically derived relationships between structural quantities such as atom positions or torsional angles on the one hand and observable quantities such as squared structure factor amplitudes, NOE intensities or 3 J-coupling constants on the other. The standardly used relation connecting 3 J-couplings to torsional angles is the Karplus relation, which is used in protein structure refinement as well as in the evaluation of simulated properties of proteins. The accuracy of the simple and generalised Karplus relations is investigated using side-chain structural and 3 J αβ-coupling data for three different proteins, Plastocyanin, Lysozyme, and FKBP, for which such data are available. The results show that the widely used Karplus relations are only a rough estimate for the relation between 3 J αβ-couplings and the corresponding Ï?1-angle in proteins.
Content Type Journal Article
Category Article
Pages 1-24
DOI 10.1007/s10858-012-9634-5
Authors
Denise Steiner, Laboratory of Physical Chemistry, ETH, Swiss Federal Institute of Technology, 8093 Zurich, Switzerland
Jane R. Allison, Laboratory of Physical Chemistry, ETH, Swiss Federal Institute of Technology, 8093 Zurich, Switzerland
Andreas P. Eichenberger, Laboratory of Physical Chemistry, ETH, Swiss Federal Institute of Technology, 8093 Zurich, Switzerland
Wilfred F. van Gunsteren, Laboratory of Physical Chemistry, ETH, Swiss Federal Institute of Technology, 8093 Zurich, Switzerland
4D APSY-HBCB(CG)CDHD experiment for automated assignment of aromatic amino acid side chains in proteins
4D APSY-HBCB(CG)CDHD experiment for automated assignment of aromatic amino acid side chains in proteins
Abstract A four-dimensional (4D) APSY (automated projection spectroscopy)-HBCB(CG)CDHD experiment is presented. This 4D experiment correlates aromatic with aliphatic carbon and proton resonances from the same amino acid side chain of proteins in aqueous solution. It thus allows unambiguous sequence-specific assignment of aromatic amino acid ring signals based on backbone assignments. Compared to conventional 2D approaches, the inclusion of evolution periods on 1Hβ and 13Cδ...
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09-30-2011 08:01 PM
Improved accuracy in measuring one-bond and two-bond 15N,13Cα coupling constants in proteins by double-inphase/antiphase (DIPAP) spectroscopy
Improved accuracy in measuring one-bond and two-bond 15N,13Cα coupling constants in proteins by double-inphase/antiphase (DIPAP) spectroscopy
Abstract An extension to HN(CO-α/β-N,Cα-J)-TROSY (Permi and Annila in J Biomol NMR 16:221â??227, 2000) is proposed that permits the simultaneous determination of the four coupling constants 1 J Nâ?²(i)Cα(i), 2 J HN(i)Cα(i), 2 J Cα(iâ??1)Nâ?²(i), and 3 J Cα(iâ??1)HN(i) in 15N,13C-labeled proteins. Contrasting the original scheme, in which two separate subspectra exhibit the 2 J CαNâ?² coupling as inphase and antiphase splitting (IPAP), we...
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06-10-2011 01:41 AM
[NMR paper] Side-chains in native and random coil protein conformations. Analysis of NMR coupling
Side-chains in native and random coil protein conformations. Analysis of NMR coupling constants and chi1 torsion angle preferences.
Related Articles Side-chains in native and random coil protein conformations. Analysis of NMR coupling constants and chi1 torsion angle preferences.
J Mol Biol. 1998 Jul 31;280(5):867-77
Authors: West NJ, Smith LJ
The behaviour of amino acid side-chains in proteins in solution has been characterised by analysing NMR 3JHalphaH beta coupling constants and crystallographic chi1 torsion angles. Side-chains both in the...
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11-17-2010 11:15 PM
Conformational dependence of 13C shielding and coupling constants for methionine
Abstract Methionine residues fulfill a broad range of roles in protein function related to conformational plasticity, ligand binding, and sensing/mediating the effects of oxidative stress. A high degree of internal mobility, intrinsic detection sensitivity of the methyl group, and low copy number have made methionine labeling a popular approach for NMR investigation of selectively labeled protein macromolecules. However, selective labeling approaches are subject to more limited information content. In order to optimize the information available from such studies, we have performed DFT...
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08-25-2010 03:51 PM
[NMR paper] The impact of direct refinement against three-bond HN-C alpha H coupling constants on
The impact of direct refinement against three-bond HN-C alpha H coupling constants on protein structure determination by NMR.
Related Articles The impact of direct refinement against three-bond HN-C alpha H coupling constants on protein structure determination by NMR.
J Magn Reson B. 1994 May;104(1):99-103
Authors: Garrett DS, Kuszewski J, Hancock TJ, Lodi PJ, Vuister GW, Gronenborn AM, Clore GM
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08-22-2010 03:33 AM
[NMR paper] The impact of direct refinement against three-bond HN-C alpha H coupling constants on
The impact of direct refinement against three-bond HN-C alpha H coupling constants on protein structure determination by NMR.
Related Articles The impact of direct refinement against three-bond HN-C alpha H coupling constants on protein structure determination by NMR.
J Magn Reson B. 1994 May;104(1):99-103
Authors: Garrett DS, Kuszewski J, Hancock TJ, Lodi PJ, Vuister GW, Gronenborn AM, Clore GM
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[U. of Ottawa NMR Facility Blog] E.COSY and the Relative Signs of Coupling Constants
E.COSY and the Relative Signs of Coupling Constants
Spin-spin coupling constants can have values greater than or less than zero. The absolute sign of the coupling constants cannot be discerned from the simple examination of a 1H NMR spectrum. The E.COSY1 (Exclusive COrrelation SpectroscopY) technique is one method which can be used to determine the relative signs of coupling constants. E.COSY is a phase sensitive COSY variant which produces off-diagonal signals showing only the active coupling (i.e. the coupling directly responsible for the cross-peak) as 2x2 antiphase square tetrads...
On the calculation of 3Jαβ-coupling constants for side chains in proteins
Linear Mode
