J. Phys. I France
Volume 2, Numéro 6, June 1992
Page(s) 995 - 1001
DOI: 10.1051/jp1:1992192
J. Phys. I France 2 (1992) 995-1001

Dynamics of hydration water in protein

M.-C. Bellissent-Funel1, J. Teixeira1, K.F. Bradley2 and S. H. Chen2

1  Laboratoire Léon Brillouin (CEA-CNRS), CEN-Saclay, 91191 Gif-sur-Yvette, France
2  Nuclear Engineering Department, M.I.T. Cambridge, MA 02139, U.S.A.

(Received 31 December 1991, accepted in final form 10 February 1992)

Incoherent quasi-elastic neutron scattering studies of in vivo deuterated C-phycocyanin, at different levels of hydration, have been made. We show that the mobility at high temperature, ( $\sim 300$ K) of the water molecules near the protein surface can be described by relatively simple models. At full hydration the high temperature data can be interpreted using a model where each water molecule is diffusing in a confined space of 3 Å in radius. At low hydration, and 298 K, the diffusional behaviour is typical of jump diffusion with a residence time 10 times larger than the one in bulk water at the same temperature.

© Les Editions de Physique 1992