Related ArticlesRefined NMR structure of alpha-sarcin by 15N-1H residual dipolar couplings.
Eur Biophys J. 2005 Nov;34(8):1057-65
Authors: García-Mayoral MF, Pantoja-Uceda D, Santoro J, Martínez del Pozo A, Gavilanes JG, Rico M, Bruix M
(15)N-(1)H residual dipolar couplings (RDC) have been used as additional restraints to refine the solution structure of the ribotoxin alpha-sarcin. The RDC values were obtained by partial alignment of alpha-sarcin in the binary mixture of n-dodecyl hexa(ethylene glycol)/hexanol. A total of 131 RDCs were measured and 106 were introduced in the final steps of the calculation protocol following the main calculation based on nuclear Overhauser enhancements and torsion angle restraints. A homogeneous family of 81 conformers was obtained. The resulting average pairwise root-mean-square deviation corresponding to the superposition of the 20 best structures is 0.69+/-0.12 A for the backbone and 1.29+/-0.14 A for all heavy atoms. The new structural features derived from the refined structure, compared with the non-refined structure of alpha-sarcin, consist of new hydrogen bonds and a better definition of the backbone conformation. In particular, the loop segment spanning Gly 60 to Lys 70 shows a single conformation, corresponding to the most populated family of conformers observed in the unrefined structure. The information derived from the analysis of the refined structure and the comparison with the homologous protein restrictocin could help in establishing further structure-function relationships concerning alpha-sarcin which can be reasonably extrapolated to other members of the ribotoxin family.
Residual dipolar couplings: are multiple independent alignments always possible?
Residual dipolar couplings: are multiple independent alignments always possible?
Abstract RDCs for the 14 kDa protein hen egg-white lysozyme (HEWL) have been measured in eight different alignment media. The elongated shape and strongly positively charged surface of HEWL appear to limit the protein to four main alignment orientations. Furthermore, low levels of alignment and the proteinâ??s interaction with some alignment media increases the experimental error. Together with heterogeneity across the alignment media arising from constraints on temperature, pH and ionic strength for some...
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12-26-2010 04:43 AM
[NMR paper] Sensitivity of NMR residual dipolar couplings to perturbations in folded and denature
Sensitivity of NMR residual dipolar couplings to perturbations in folded and denatured staphylococcal nuclease.
Related Articles Sensitivity of NMR residual dipolar couplings to perturbations in folded and denatured staphylococcal nuclease.
Biochemistry. 2005 May 3;44(17):6392-403
Authors: Sallum CO, Martel DM, Fournier RS, Matousek WM, Alexandrescu AT
The invariance of NMR residual dipolar couplings (RDCs) in denatured forms of staphylococcal nuclease to changes in denaturant concentration or amino acid sequence has previously been attributed...
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11-25-2010 08:21 PM
[NMR paper] Residual dipolar couplings in NMR structure analysis.
Residual dipolar couplings in NMR structure analysis.
Related Articles Residual dipolar couplings in NMR structure analysis.
Annu Rev Biophys Biomol Struct. 2004;33:387-413
Authors: Lipsitz RS, Tjandra N
Residual dipolar couplings (RDCs) have recently emerged as a new tool in nuclear magnetic resonance (NMR) with which to study macromolecular structure and function in a solution environment. RDCs are complementary to the more conventional use of NOEs to provide structural information. While NOEs are local-distance restraints, RDCs provide...
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11-24-2010 09:25 PM
[NMR paper] Residual dipolar couplings: synergy between NMR and structural genomics.
Residual dipolar couplings: synergy between NMR and structural genomics.
Related Articles Residual dipolar couplings: synergy between NMR and structural genomics.
J Biomol NMR. 2002 Jan;22(1):1-8
Authors: Al-Hashimi HM, Patel DJ
Structural genomics is on a quest for the structure and function of a significant fraction of gene products. Current efforts are focusing on structure determination of single-domain proteins, which can readily be targeted by X-ray crystallography, NMR spectroscopy and computational homology modeling. However,...
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11-24-2010 08:49 PM
[NMR paper] Protein structural motif recognition via NMR residual dipolar couplings.
Protein structural motif recognition via NMR residual dipolar couplings.
Related Articles Protein structural motif recognition via NMR residual dipolar couplings.
J Am Chem Soc. 2001 Feb 14;123(6):1222-9
Authors: Andrec M, Du P, Levy RM
NMR residual dipolar couplings have great potential to provide rapid structural information for proteins in the solution state. This information even at low resolution may be used to advantage in proteomics projects that seek to annotate large numbers of gene products for entire genomes. In this paper, we...
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11-19-2010 08:32 PM
Facile measurement of 1Hâ??15N residual dipolar couplings in larger perdeuterated pro
Abstract We present a simple method, ARTSY, for extracting 1JNH couplings and 1Hâ??15N RDCs from an interleaved set of two-dimensional 1Hâ??15N TROSY-HSQC spectra, based on the principle of quantitative J correlation. The primary advantage of the ARTSY method over other methods is the ability to measure couplings without scaling peak positions or altering the narrow line widths characteristic of TROSY spectra. Accuracy of the method is demonstrated for the model system GB3. Application to the catalytic core domain of HIV integrase, a 36 kDa homodimer with unfavorable spectral...
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08-14-2010 04:19 AM
A structure refinement protocol combining NMR residual dipolar couplings and small angle scattering restraints
A structure refinement protocol combining NMR residual dipolar couplings and small angle scattering restraints
F. Gabel, B. Simon, M. Nilges, M. Petoukhov, D. Svergun and M. Sattler
Journal of Biomolecular NMR; 2008; 41(4); pp 199-208
Abstract:
We present the implementation of a target function based on Small Angle Scattering data (Gabel et al. Eur Biophys J 35(4):313–327, 2006) into the Crystallography and NMR Systems (CNS) and demonstrate its utility in NMR structure calculations by simultaneous application of small angle scattering (SAS) and residual dipolar coupling (RDC)...
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09-21-2008 11:30 PM
Theoretical framework for NMR residual dipolar couplings in unfolded proteins
Theoretical framework for NMR residual dipolar couplings in unfolded proteins
O. I. Obolensky, Kai Schlepckow, Harald Schwalbe and A. V. Solov’yov
Journal of Biomolecular NMR; 2007; 39(1) pp 1-16
Abstract:
A theoretical framework for the prediction of nuclear magnetic resonance (NMR) residual dipolar couplings (RDCs) in unfolded proteins under weakly aligning conditions is presented. The unfolded polypeptide chain is modeled as a random flight chain while the alignment medium is represented by a set of regularly arranged obstacles. For the case of bicelles oriented perpendicular to...