PARTIAL MOLAR VOLUMES OF THE AMINO-ACID SIDE-CHAINS OF PROTEINS IN AQUEOUS-SOLUTION - SOME COMMENTS ON THEIR ESTIMATION USING PARTIAL MOLAR VOLUMES OF AMINO-ACIDS AND SMALL PEPTIDES

The partial molar volumes of some amino acid side-chains were determined in two recent studies [Makhatadze, G. I., et al. (1990) Biopolymers 30, 1001, and Reading, J. F. & Hedwig, G. R. (1990) J. Chem. Soc. Faraday Trans. 86, 3117] using partial molar volume data, V-(2)0, in aqueous solution at 25-degrees-C for some peptides of sequence Gly-X-Gly, where X is an amino acid. These side-chain partial molar volumes are critically compared with those obtained using V-2(0) data for amino acids. It is concluded that side-chain partial molar volumes calculated using V-2(0) data for the tripeptides are better estimates of side-chain partial molar volumes in proteins than are those determined using V-2(0) data for amino acids.