Change of hydrogen bond kinetics of protein hydration water upon percolation transition

Nakagawa, Hiroshi   ; Kataoka, Mikio

Water network pattern and dynamics are determined by hydrogen bonding. The physical properties of the hydration water is different from that of bulk water. The hydration affects the protein biological function. Here, we show the importance of hydration for protein dynamics and the percolation of hydration water by inelastic neutron scattering and molecular dynamics simulation. The dynamical transition of protein is highly correlated with the percolation transition of the hydration water, and then the percolation induces the protein dynamical transition. The dynamical coupling between protein and hydration water is essential for protein dynamics and its biological function.