Although it is well known that water is essential for biological function, it has been a challenge to determine how water behaves near biomacromolecular interfaces, and what role water plays in influencing the dynamic...Although it is well known that water is essential for biological function, it has been a challenge to determine how water behaves near biomacromolecular interfaces, and what role water plays in influencing the dynamics of the biochemical machinery. By adopting a vibrational labeling strategy coupled with ultrafast two-dimensional infrared （2D-IR） spectroscopy, it has recently become possible to study hydration dynamics, site specifically at the surface of proteins and model membranes. We review our recent progress in measuring hydration dynamics in contexts ranging from small-molecule solutes to biomacromolecules in dilute, viscous, and crowded environments.展开更多
The dynamic or glass transition in biomolecules is important to their functioning. Also essential is the transition between the protein native state and the unfolding process. To better understand these transitions, w...The dynamic or glass transition in biomolecules is important to their functioning. Also essential is the transition between the protein native state and the unfolding process. To better understand these transitions, we use Fourier transform infrared spectroscopy to study the vibrational bending and stretching modes of hydrated lysozymes across a wide temperature range. We find that these transitions are triggered by the strong hydrogen bond coupling between the protein and hydration water. More precisely, we demonstrate that in both cases the water properties dominate the evolution of the system. We find that two characteristic temperatures are relevant： in the supercooled regime of confined water, the fragile-to-strong dynamic transition occurs at TL, and in the stable liquid phase, T＊ 315 ± 5 K characterizes the behavior of both isothermal compressibility KT（T, P） and the coefficient of thermal expansion ap（T, P）.展开更多
基金supported by the National Science Foundation (No.CHE-0748501)the National Institutes of Health (No.RR012255)the Camille & Henry Dreyfus Foundation
文摘Although it is well known that water is essential for biological function, it has been a challenge to determine how water behaves near biomacromolecular interfaces, and what role water plays in influencing the dynamics of the biochemical machinery. By adopting a vibrational labeling strategy coupled with ultrafast two-dimensional infrared （2D-IR） spectroscopy, it has recently become possible to study hydration dynamics, site specifically at the surface of proteins and model membranes. We review our recent progress in measuring hydration dynamics in contexts ranging from small-molecule solutes to biomacromolecules in dilute, viscous, and crowded environments.
文摘The dynamic or glass transition in biomolecules is important to their functioning. Also essential is the transition between the protein native state and the unfolding process. To better understand these transitions, we use Fourier transform infrared spectroscopy to study the vibrational bending and stretching modes of hydrated lysozymes across a wide temperature range. We find that these transitions are triggered by the strong hydrogen bond coupling between the protein and hydration water. More precisely, we demonstrate that in both cases the water properties dominate the evolution of the system. We find that two characteristic temperatures are relevant： in the supercooled regime of confined water, the fragile-to-strong dynamic transition occurs at TL, and in the stable liquid phase, T＊ 315 ± 5 K characterizes the behavior of both isothermal compressibility KT（T, P） and the coefficient of thermal expansion ap（T, P）.
