Dataset Information

Ultrafast Dynamics of Water-Protein Coupled Motions around the Surface of Eye Crystallin.

ABSTRACT: Water dynamics on the protein surface mediate both protein structure and function. However, many questions remain about the role of the protein hydration layers in protein fluctuations and how the dynamics of these layers relate to specific protein properties. The fish eye lens protein ?M7-crystallin (?M7) is found in vivo at extremely high concentrations nearing the packing limit, corresponding to only a few water layers between adjacent proteins. In this study, we conducted a site-specific probing of hydration water motions and side-chain dynamics at nine selected sites around the surface of ?M7 using a tryptophan scan with femtosecond spectroscopy and NMR nuclear spin relaxation (NSR). We observed correlated fluctuations between hydration water and protein side chains on the time scales of a few picoseconds and hundreds of picoseconds, corresponding to local reorientations and network restructuring, respectively. These motions are heterogeneous over the protein surface and relate to the various steric and chemical properties of the local protein environment. Overall, we found that ?M7 has relatively slower water dynamics within the hydration shell than a similar ?-sheet protein, which may contribute to the high packing limit of this unique protein.

SUBMITTER: Houston P

PROVIDER: S-EPMC7261499 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

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Ultrafast Dynamics of Water-Protein Coupled Motions around the Surface of Eye Crystallin.

Houston Patrick P Macro Nicolas N Kang Minhee M Chen Long L Yang Jin J Wang Lijuan L Wu Zhengrong Z Zhong Dongping D

Journal of the American Chemical Society 20200211 8

Water dynamics on the protein surface mediate both protein structure and function. However, many questions remain about the role of the protein hydration layers in protein fluctuations and how the dynamics of these layers relate to specific protein properties. The fish eye lens protein γM7-crystallin (γM7) is found in vivo at extremely high concentrations nearing the packing limit, corresponding to only a few water layers between adjacent proteins. In this study, we conducted a site-specific pro ...[more]

PMID: 31991083

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Dataset Information

Ultrafast Dynamics of Water-Protein Coupled Motions around the Surface of Eye Crystallin.

Publications

Ultrafast Dynamics of Water-Protein Coupled Motions around the Surface of Eye Crystallin.

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