Observation of molecular reorientation in ice by proton and deuterium magnetic resonance

Wittebort, Richard J.; Usha, M.G.; Ruben, D. J.; Wemmer, David E.; Pines, Alexander

doi:10.1021/ja00225a013

Cited by 133 publications

(165 citation statements)

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“…15͒ and the Thr -CH 3 rotations and the surrounding WMRs. For comparison, WMRs in bulk ice 20,21 and in tetrahydrofuran ͑THF͒ gas hydrate 15 were also shown in the same table. The energy barrier of the AFP͑i͒ Thr -CH 3 rotation is smaller than that of the AFP͑i +4,8͒ Ala -CH 3 rotation.…”

Section: Fig 2 C-h Internuclear-distance Dependentmentioning

confidence: 99%

Antifreeze protein NMR sensor to detect water molecular reorientation in the surface of ice

Mao

Lin

2009

The Journal of Chemical Physics

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The century-old puzzle of the existence of a quasiliquid layer in the surface of ice was revisited using ice-surface binding type I antifreeze proteins with specific side chain C13 labeled methyl groups. Variable temperature dependent C13 spin lattice relaxation NMR experiments were carried out below 0 °C to probe the water molecular reorientations surrounding the methyl groups. The result shows that water molecular reorientations in ice surface are much more dynamic than those in bulk ice. This study demonstrates that antifreeze proteins can be used as a sensor to detect the dynamics of water in the surface of ice.

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Section: Fig 2 C-h Internuclear-distance Dependentmentioning

confidence: 99%

Antifreeze protein NMR sensor to detect water molecular reorientation in the surface of ice

Mao

Lin

2009

The Journal of Chemical Physics

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“…Another possible type of internal motion is a 180°flip around the C 2 axis of the water molecule. Due to symmetry, however, this motion does not affect A I for 17 O and, besides, is probably orders of magnitude too slow (Fujara et al, 1988;Wittebort et al, 1988;Larsson et al, 1991) to contribute to motional averaging on the time-scale (t R ) on which the time correlation function decays.…”

Section: Internal Watermentioning

confidence: 99%

Protein Hydration Dynamics in Aqueous Solution: A Comparison of Bovine Pancreatic Trypsin Inhibitor and Ubiquitin by Oxygen-17 Spin Relaxation Dispersion

Денисов

Halle

1995

Journal of Molecular Biology

162

177

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Water oxygen-17 spin relaxation was used to study hydration and dynamics Condensed Matter Magnetic Resonance Group, Chemical of the globular proteins bovine pancreatic trypsin inhibitor (BPTI) and ubiquitin in aqueous solution. The frequency dispersion of the longitudinal Center, Lund University P. O. Box 124, S-22100 Lund and transverse relaxation rates was measured over the Larmor frequency Sweden range 2.6 to 49 MHz in the pD range 2 to 11 at 27°C. While the protein-induced relaxation enhancement was similar for the two proteins at high frequencies, it was an order of magnitude smaller for ubiquitin than for BPTI at low frequencies. This difference was ascribed to the abscence, in ubiquitin, of highly ordered internal water molecules, which are known to be present in BPTI and in most other globular proteins. These observations demonstrate that the water relaxation dispersion in protein solutions is essentially due to a few structural water molecules buried within the protein matrix, but exchanging rapidly with the external water. The relaxation data indicate that the internal water molecules of BPTI exchange with bulk water on the time-scale 10 −8 to 10 −6 second thus lowering the recently reported upper bound on the residence time of these internal water molecules by four orders of magnitude, and implying that local unfolding occurs on the submicrosecond time-scale. The water molecules residing at the surface of the two proteins were found to be highly mobile, with an average rotational correlation time of approximately 20 picoseconds. For both proteins, the oxygen-17 relaxation depended only very weakly on pD, showing that ionic residues do not perturb hydration water dynamics more than other surface residues. We believe that the present results resolve the long-standing controversy regarding the mechanism behind the spin relaxation dispersion of water nuclei in protein solutions, thus establishing oxygen-17 relaxation as a powerful tool for studies of structurally and functionally important water molecules in proteins and other biomolecules.

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“…This may be contrasted with 2 H which does move and the orientation of its EFG tensor changes among four tetrahedral orientations. For ice, 2 H NMR lineshapes as a function of temperature show complete narrowing of the first-order lineshape to a pseudoisotropic lineshape, corresponding to an effective C Q of zero [31]. 17 O NMR, however, shows narrowing of the CT to a new anisotropic lineshape which is still present at the melting point, i.e., there is incomplete averaging of the second-order lineshape ( Figure 11a).…”

Section: Central Transition Lineshapesmentioning

confidence: 99%

Quadrupolar NMR to Investigate Dynamics in Solid Materials

O’Dell

Ratcliffe

1996

eMagRes

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Observation of molecular reorientation in ice by proton and deuterium magnetic resonance

Cited by 133 publications

References 0 publications

Antifreeze protein NMR sensor to detect water molecular reorientation in the surface of ice

Antifreeze protein NMR sensor to detect water molecular reorientation in the surface of ice

Protein Hydration Dynamics in Aqueous Solution: A Comparison of Bovine Pancreatic Trypsin Inhibitor and Ubiquitin by Oxygen-17 Spin Relaxation Dispersion

Quadrupolar NMR to Investigate Dynamics in Solid Materials

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