Characteristics of zero-quantum correlation spectroscopy in MAS NMR experiments.
J Magn Reson. 2010 Dec;207(2):197-205
Authors: Köneke SG, van Beek JD, Ernst M, Meier BH
Zero-quantum coherence generation and reconversion in magic-angle spinning solid-state NMR is analyzed. Two methods are discussed based on implementations using symmetry-based pulse sequences that utilize either isotropic J couplings or dipolar couplings. In either case, the decoupling of abundant proton spins plays a crucial role for the efficiency of the zero-quantum generation. We present optimized sequences for measuring zero-quantum single-quantum correlation spectra in solids, achieving an efficiency of 50% in ubiquitin. The advantages and disadvantages of zero-quantum single-quantum over single-quantum single-quantum correlation spectroscopy are explored, and similarities and differences with double-quantum single-quantum correlation spectroscopy are discussed. Finally, possible application of zero-quantum single-quantum experiments to polypeptides, where it can lead to better spectral resolution is investigated using ubiquitin, where we find high efficiency and high selectivity, but also increased line widths in the MQ dimension.
Sugar-to-base correlation in nucleic acids with a 5D APSY-HCNCH or two 3D APSY-HCN experiments
Sugar-to-base correlation in nucleic acids with a 5D APSY-HCNCH or two 3D APSY-HCN experiments
Abstract A five-dimensional (5D) APSY (automated projection spectroscopy) HCNCH experiment is presented, which allows unambiguous correlation of sugar to base nuclei in nucleic acids. The pulse sequence uses multiple quantum (MQ) evolution which enables long constant-time evolution periods in all dimensions, an improvement that can also benefit non-APSY applications. Applied with an RNA with 23 nucleotides the 5D APSY-HCNCH experiment produced a complete and highly precise 5D chemical shift...
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12-07-2011 10:22 PM
Three-dimensional deuterium-carbon correlation experiments for high-resolution solid-state MAS NMR spectroscopy of large proteins
Three-dimensional deuterium-carbon correlation experiments for high-resolution solid-state MAS NMR spectroscopy of large proteins
Abstract Well-resolved 2Hâ??13C correlation spectra, reminiscent of 1Hâ??13C correlations, are obtained for perdeuterated ubiquitin and for perdeuterated outer-membrane protein G (OmpG) from E. coli by exploiting the favorable lifetime of 2H double-quantum (DQ) states. Sufficient signal-to-noise was achieved due to the short deuterium T 1, allowing for high repetition rates and enabling 3D experiments with a 2Hâ??13C transfer step in a reasonable time....
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11-01-2011 01:52 AM
Origin and removal of mixed-phase artifacts in gradient sensitivity enhanced heteronuclear single quantum correlation spectra
Origin and removal of mixed-phase artifacts in gradient sensitivity enhanced heteronuclear single quantum correlation spectra
Abstract Here we describe phasing anomalies observed in gradient sensitivity enhanced 15N-1H HSQC spectra, and analyze their origin. It is shown that, as a result of 15N off-resonance effects, dispersive contributions to the 1H signal become detectable, and lead to 15N-offset dependent phase errors. Strategies that effectively suppress these artifacts are presented.
Content Type Journal Article
Category Article
Pages 199-207
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09-30-2011 08:01 PM
Multiplet-filtered and gradient-selected zero-quantum TROSY experiments for 13C1H3 methyl groups in proteins
Multiplet-filtered and gradient-selected zero-quantum TROSY experiments for 13C1H3 methyl groups in proteins
Abstract Multiplet-filtered and gradient-selected heteronuclear zero-quantum coherence (gsHZQC) TROSY experiments are described for measuring 1Hâ??13C correlations for 13CH3 methyl groups in proteins. These experiments provide improved suppression of undesirable, broad outer components of the heteronuclear zero-quantum multiplet in medium-sized proteins, or in flexible sites of larger proteins, compared to previously described HZQC sequences (Tugarinov et al. in J Am Chem Soc...
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09-17-2011 10:20 AM
[NMR paper] Structural studies of biomaterials using double-quantum solid-state NMR spectroscopy.
Structural studies of biomaterials using double-quantum solid-state NMR spectroscopy.
Related Articles Structural studies of biomaterials using double-quantum solid-state NMR spectroscopy.
Annu Rev Phys Chem. 2003;54:531-71
Authors: Drobny GP, Long JR, Karlsson T, Shaw W, Popham J, Oyler N, Bower P, Stringer J, Gregory D, Mehta M, Stayton PS
Proteins directly control the nucleation and growth of biominerals, but the details of molecular recognition at the protein-biomineral interface remain poorly understood. The elucidation of recognition...
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11-24-2010 08:49 PM
[NMR paper] Three-dimensional electrophoretic NMR correlation spectroscopy.
Three-dimensional electrophoretic NMR correlation spectroscopy.
Related Articles Three-dimensional electrophoretic NMR correlation spectroscopy.
J Magn Reson. 2000 Dec;147(2):361-5
Authors: He Q, Lin W, Liu Y, Li E
A novel method of three-dimensional electrophoretic NMR correlation spectroscopy (3D EP-COSY) has been proposed, developed, and implemented. It has a demonstrated potential of facilitating simultaneous structural assignments of multiple proteins in mixtures. The principle is to add a pulsed DC electric field that introduces a new...
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11-19-2010 08:29 PM
Four-dimensional heteronuclear correlation experiments for chemical shift assignment of solid proteins
Four-dimensional heteronuclear correlation experiments for chemical shift assignment of solid proteins
W. Trent Franks, Kathryn D. Kloepper, Benjamin J. Wylie and Chad M. Rienstra
Journal of Biomolecular NMR; 2007; 39(2); pp 107 - 131
Abstract:
Chemical shift assignment is the first step in all established protocols for structure determination of uniformly labeled proteins by NMR. The explosive growth in recent years of magic-angle spinning (MAS) solid-state NMR (SSNMR) applications is largely attributable to improved methods for backbone and side-chain chemical shift correlation...
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08-05-2008 01:33 PM
Double quantum filtering homonuclear MAS NMR correlation spectra: a tool for membrane protein studies
Double quantum filtering homonuclear MAS NMR correlation spectra: a tool for membrane protein studies
Jakob J. Lopez, Christoph Kaiser, Sarika Shastri and Clemens Glaubitz
Journal of Biomolecular NMR; 2008; 41(2) pp 97 - 104
Abstract:
13C homonuclear correlation spectra based on proton driven spin diffusion (PDSD) are becoming increasingly important for obtaining distance constraints from multiply labeled biomolecules by MAS NMR. One particular challenging situation arises when such constraints are to be obtained from spectra with a large natural abundance signal background which...