Structural studies of globular proteins by nmr can be enhanced by the use of isotope enrichment. We have been working with proteins enriched with 15N, and with both 15N and 13C. Due to the isotope enrichment we could assign several large proteins with up to 186 residues and could address structural questions. Furthermore, we can accurately measure heteronuclear and homonuclear vicinal coupling constants. This involves in part multidimensional multiple resonance experiments. This is important for characterization of minor conformational changes caused by mutations. We have also made use of isotope enrichment to study the internal mobility of proteins. We also have developed novel methods for measuring accurately 15N relaxation parameters, in particular transverse relaxation rates. This has led us toward a method for directly mapping spectral density functions of the rotational motions of N-H bond vectors in proteins. The protein systems that are discussed include the unlabeled proteins kistrin and cytochrome c551, and the labeled proteins eglin c, a flavodoxin, and human dihydrofolate reductase.
Three-dimensional triple-resonance NMR Spectroscopy of isotopically enriched proteins
Three-dimensional triple-resonance NMR Spectroscopy of isotopically enriched proteins
Publication year: 2011
Source: Journal of Magnetic Resonance, Volume 213, Issue 2, December 2011, Pages 423-441</br>
Lewis E.*Kay, Mitsuhiko*Ikura, Rolf*Tschudin, Ad*Bax</br>
Four new and complementary three-dimensional triple-resonance experiments are described for obtaining complete backboneH,C, andN resonance assignments of proteins uniformly enriched withC andN. The new methods all rely onH detection and use multiple magnetization transfers through well-resolved one-bondJcouplings. Therefore, the...
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12-11-2011 07:57 AM
NMR studies of protein structure and dynamics
NMR studies of protein structure and dynamics
Publication year: 2011
Source: Journal of Magnetic Resonance, Volume 213, Issue 2, December 2011, Pages 477-491</br>
Lewis E.*Kay</br>
Recent advances in solution NMR spectroscopy have significantly extended the spectrum of problems that can now be addressed with this technology. In particular, studies of proteins with molecular weights on the order of 100*kDa are now possible at a level of detail that was previously reserved for much smaller systems. An example of the sort of information that is now accessible is provided in a study of...
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Isotope labeling strategies for NMR studies of RNA
Isotope labeling strategies for NMR studies of RNA
Abstract The known biological functions of RNA have expanded in recent years and now include gene regulation, maintenance of sub-cellular structure, and catalysis, in addition to propagation of genetic information. As for proteins, RNA function is tightly correlated with structure. Unlike proteins, structural information for larger, biologically functional RNAs is relatively limited. NMR signal degeneracy, relaxation problems, and a paucity of long-range 1Hâ??1H dipolar contacts have limited the utility of traditional NMR approaches....
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01-09-2011 12:46 PM
Recent advances in segmental isotope labeling of proteins: NMR applications to large proteins and glycoproteins
Recent advances in segmental isotope labeling of proteins: NMR applications to large proteins and glycoproteins
Abstract In the last 15 years substantial advances have been made to place isotope labels in native and glycosylated proteins for NMR studies and structure determination. Key developments include segmental isotope labeling using Native Chemical Ligation, Expressed Protein Ligation and Protein Trans-Splicing. These advances are pushing the size limit of NMR spectroscopy further making larger proteins accessible for this technique. It is just emerging that segmental isotope...
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Dynamics and interactions of glycoconjugates probed by stable-isotope-assisted NMR spectroscopy.
Dynamics and interactions of glycoconjugates probed by stable-isotope-assisted NMR spectroscopy.
Dynamics and interactions of glycoconjugates probed by stable-isotope-assisted NMR spectroscopy.
Methods Enzymol. 2010;478:305-22
Authors: Yamaguchi Y, Kato K
Unique advantages offered by nuclear magnetic resonance (NMR) spectroscopy provide high-resolution information not only on structures but also on dynamics and interactions of glycoconjugates in solution. These benefits are further enhanced by applying stable-isotope-labeling techniques, which we...
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12-31-2010 07:03 PM
[NMR paper] NMR studies of protein structure and dynamics.
NMR studies of protein structure and dynamics.
Related Articles NMR studies of protein structure and dynamics.
J Magn Reson. 2005 Apr;173(2):193-207
Authors: Kay LE
Recent advances in solution NMR spectroscopy have significantly extended the spectrum of problems that can now be addressed with this technology. In particular, studies of proteins with molecular weights on the order of 100 kDa are now possible at a level of detail that was previously reserved for much smaller systems. An example of the sort of information that is now accessible is...
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11-25-2010 08:21 PM
[NMR paper] Some NMR experiments and a structure determination employing a [15N,2H] enriched prot
Some NMR experiments and a structure determination employing a enriched protein.
Related Articles Some NMR experiments and a structure determination employing a enriched protein.
J Biomol NMR. 1998 Aug;12(2):259-76
Authors: Mal TK, Matthews SJ, Kovacs H, Campbell ID, Boyd J
We present the results of studies of an aqueous sample of a highly enriched protein, the SH3 domain from Fyn. Measurements of 1H relaxation and interactions between H2O solvent and exchangeable protons are given, as well as a method for increasing the effective...
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11-17-2010 11:15 PM
[NMR paper] Uniform 13C isotope labeling of proteins with sodium acetate for NMR studies: applica
Uniform 13C isotope labeling of proteins with sodium acetate for NMR studies: application to human carbonic anhydrase II.
Related Articles Uniform 13C isotope labeling of proteins with sodium acetate for NMR studies: application to human carbonic anhydrase II.
Biochemistry. 1991 May 7;30(18):4491-4
Authors: Venters RA, Calderone TL, Spicer LD, Fierke CA
Uniform double labeling of proteins for NMR studies can be prohibitively expensive, even with an efficient expression and purification scheme, due largely to the high cost of glucose. We...