Search results for: Alfred G. Redfield

Items from 1 to 11 out of 11 results

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High-resolution NMR field-cycling device for full-range relaxation and structural studies of biopolymers on a shared commercial instrument

Alfred G. Redfield

Journal of Biomolecular NMR > 2012 > 52 > 2 > 159-177

Improvements are described in a shuttling field-cycling device (Redfield in Magn Reson Chem 41:753–768, 2003), designed to allow widespread access to this useful technique by configuring it as a removable module to a commercial 500 MHz NMR instrument. The main improvements described here, leading to greater versatility, high reliability and simple construction, include: shuttling provided by a linear...

article

Enzymology with a Spin-Labeled Phospholipase C: Soluble Substrate Binding by ³¹ P NMR from 0.005 to 11.7 T

Mingming Pu, Jianwen Feng, Alfred G. Redfield, Mary F. Roberts

Biochemistry > 2009 > 48 > 35 > 8282 - 8284

article

Phospholipid Reorientation at the Lipid/Water Interface Measured by High Resolution 31P Field Cycling NMR Spectroscopy

Mary F. Roberts, Alfred G. Redfield, Udayan Mohanty

Biophysical Journal > 2009 > 97 > 1 > 132-141

The magnetic field dependence of the ³¹P spin-lattice relaxation rate, R₁, of phospholipids can be used to differentiate motions for these molecules in a variety of unilamellar vesicles. In particular, internal motion with a 5- to 10-ns correlation time has been attributed to diffusion-in-a-cone of the phosphodiester region, analogous to motion of a cylinder in a liquid hydrocarbon. We use the temperature...

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Phosphatidylcholine “Wobble” in Vesicles Assessed by High-Resolution ¹³ C Field Cycling NMR Spectroscopy

V. N. Sivanandam, Jingfei Cai, Alfred G. Redfield, Mary F. Roberts

Journal of the American Chemical Society > 2009 > 131 > 10 > 3420 - 3421

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Insights into the Structural Specificity of the Cytotoxicity of 3-Deoxyphosphatidylinositols

Yanling K. Wang, Wei Chen, Derek Blair, Mingming Pu, more

Journal of the American Chemical Society > 2008 > 130 > 24 > 7746 - 7755

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Rotation of Lipids in Membranes: Molecular Dynamics Simulation, 31P Spin-Lattice Relaxation, and Rigid-Body Dynamics

Jeffery B. Klauda, Mary F. Roberts, Alfred G. Redfield, Bernard R. Brooks, more

Biophysical Journal > 2008 > 94 > 8 > 3074-3083

Molecular dynamics simulations and ³¹P-NMR spin-lattice (R₁) relaxation rates from 0.022 to 21.1 T of fluid phase dipalmitoylphosphatidylcholine bilayers are compared. Agreement between experiment and direct prediction from simulation indicates that the dominant slow relaxation (correlation) times of the dipolar and chemical shift anisotropy spin-lattice relaxation are ∼10ns and 3ns, respectively...

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High-Resolution ³¹ P Field Cycling NMR as a Probe of Phospholipid Dynamics

Mary F. Roberts, Alfred G. Redfield

Journal of the American Chemical Society > 2004 > 126 > 42 > 13765 - 13777

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High-Resolution Field-Cycling NMR Studies of a DNA Octamer as a Probe of Phosphodiester Dynamics and Comparison with Computer Simulation ^†

Mary F. Roberts, Qizhi Cui, Christopher J. Turner, David A. Case, more

Biochemistry > 2004 > 43 > 12 > 3637 - 3650

article

Field-cycling method with central transition readout for pure quadrupole resonance detection in dilute systems

Dmitri Ivanov, Alfred G. Redfield

Journal of Magnetic Resonance > 2004 > 166 > 1 > 19-27

We present a modification of a field-cycling method which uses the NMR signal of the central transition at high field to indirectly detect zero-field quadrupole transitions. The quadrupole transitions at zero-field are detected as changes in the overall intensity of the central transition signal after the field cycle, and the method is relatively immune to lineshape distortions of the central transition...