Picture of Protein Hydration

This section summarizes and coordinates the results of measurements described in Sections II—V. The discussion is based on a picture of the hydration process developed by Careri et al. (1980) and by Rupley et al. (1983). Others have presented similar pictures (Finney and Poole, 1984 Finney et al., 1982). Literature citations are minimal, and it is hoped that the reader will consult previous sections for more complete documentation. Table VII summarizes the chemistry of the protein at various hydration levels and also the principal points of the discussion that follows. 

Heat capacity of adsorbed water between that of ice and liquid  

Folded state stable solution value At low hydration protons redistribute among ionizable groups, to reduce number of charges At 0.05 h normalization of pK At 0.07 A phase transition (2-dimensional condensation) 

25 Plateau in sorption isotherm (60-220) Small differences in partial molar quantities for transfer of water into hydration layer, which, with increasing hydration, decrease to near 0 average values AGi = -0.2, AHj = —1.1 kcal/mol, AVj = 0 for A a 0.15 

Structure of protein at low hydration same as that for full hydration, at 1 A level of comparison 

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