Influence of Hydrophobicity of Amino Acid Side Chains on Volume and Viscosity Properties of Their Aqueous Solutions
The standard partial molar volumes (V2,cp) and coefficients of viscosity (Br|) at 298.15 K for aqueous solutions of amino acids containing hydrophobic and hydrophilic groups have been calculated. Based on the transition state theory of Feakins, the partial molar free energies of activation of the viscous flow of amino acids in water have been obtained. Correlations between the A(X2 values and the hydrophobic contribution (log/3') of amino acid molecules and the «packing density» (Dh) of water molecules in their hydration shells have been established. It was shown that A|X2* and V2,cp values reflect changes in the hydrophobicity of amino acid side chains and their hydrogen bonding ability.