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Dynamics and mechanism of ultrafast water-protein interactions.

ABSTRACT: Protein hydration is essential to its structure, dynamics, and function, but water-protein interactions have not been directly observed in real time at physiological temperature to our awareness. By using a tryptophan scan with femtosecond spectroscopy, we simultaneously measured the hydration water dynamics and protein side-chain motions with temperature dependence. We observed the heterogeneous hydration dynamics around the global protein surface with two types of coupled motions, collective water/side-chain reorientation in a few picoseconds and cooperative water/side-chain restructuring in tens of picoseconds. The ultrafast dynamics in hundreds of femtoseconds is from the outer-layer, bulk-type mobile water molecules in the hydration shell. We also found that the hydration water dynamics are always faster than protein side-chain relaxations but with the same energy barriers, indicating hydration shell fluctuations driving protein side-chain motions on the picosecond time scales and thus elucidating their ultimate relationship.

SUBMITTER: Qin Y

PROVIDER: S-EPMC4968723 | biostudies-literature | 2016 Jul

REPOSITORIES: biostudies-literature

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Dynamics and mechanism of ultrafast water-protein interactions.

Qin Yangzhong Y Wang Lijuan L Zhong Dongping D

Proceedings of the National Academy of Sciences of the United States of America 20160623 30

Protein hydration is essential to its structure, dynamics, and function, but water-protein interactions have not been directly observed in real time at physiological temperature to our awareness. By using a tryptophan scan with femtosecond spectroscopy, we simultaneously measured the hydration water dynamics and protein side-chain motions with temperature dependence. We observed the heterogeneous hydration dynamics around the global protein surface with two types of coupled motions, collective w ...[more]

PMID: 27339138

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Dataset Information

Dynamics and mechanism of ultrafast water-protein interactions.

Publications

Dynamics and mechanism of ultrafast water-protein interactions.

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