Thermodynamic properties of peptide solutions. Part 11. Partial molar isentropic pressure coefficients in aqueous solutions of some tripeptides that model protein side-chains.
The partial molar isentropic pressure coefficients at infinite dilution K infinity s,2 (K infinity s,2 = -(delta V infinity 2/delta p)s, where V infinity 2 is the partial molar volume at infinite dilution) have been determined for nine tripeptides in aqueous solution at 25 degrees C. The tripeptides are all of sequence glycyl-X-glycine, where X is an amino acid. These K infinity s,2 results, in conjunction with those of glycylglycylglycine, were used to estimate the amino acid side-chain contributions to K infinity s,2 of peptides. These side-chain contributions are critically compared with previous estimates based on K infinity s,2 data for the amino acids. The variation in the side-chain contributions derived using the peptide K infinity s,2 results has been rationalized in terms of likely peptide-solvent interactions.
Hedwig
G R
GR
Department of Chemistry and Biochemistry, Massey University, Palmerston North, New Zealand.
Høiland
H
H
D000595:Amino Acid Sequence; D007700:Kinetics; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000737:chemistry*; D012996:Solutions; D013816:Thermodynamics
D009842:Oligopeptides; D012996:Solutions