Additivity of the partial molar heat capacities of the amino acid side-chains of small peptides: Implications for unfolded proteins

Partial Molar Isentropic Compressions of Some Tetra- and Pentapeptides in Aqueous Solution: Implications for Group Additivity Schemes for Unfolded Proteins

“…This result suggests that, with regard to the property K • S,2 , the pentapeptide side-chain hydration differs from that in the tripeptide glyleugly. Such hydration differences must be subtle because they are certainly not significant enough to be manifested in either the partial molar volumes or heat capacities for these peptides [33,34]. In contrast, the results for the peptide glyglyserglygly suggest that the hydration of the seryl side-chain is almost identical to that in the tripeptide glysergly.…”

“…Because of the limited amount of this peptide available for the current study, two solutions were prepared using vacuum dried solid material that had been recovered from the other solutions used in this work. The sample of glyglyleuglygly used was material that had been recovered from previous studies [33,34] and then recrystallized from (water + methanol). The reproducibility of solution densities was used as a criterion of purity of the solid.…”

Densities of aqueous solutions containing model compounds of amino acids and ionic salts at T=298.15K

“…The interactions between solvent and the various constituent groups of a protein, such as the amino acid side-chains and the peptide backbone group, play a central role in the structure, the conformation and the function of proteins in aqueous solution [6][7][8][9][10]. Much thermodynamic evidence was conventionally interpreted by Hedwig and co-workers [11][12][13] as indicating the group additivity properties of the partial molar heat capacities and volumes of aqueous solutions of some peptides, which are model side-chain of proteins.…”

Property-Dependent Analysis of Aligned Proteins From Two or More Populations

“…The statistical tests will be performed for each of these properties, and the properties are assumed to be additive in the protein structure. For some properties (like molecular mass) this is self-evident, for others (like water-accessible surface area), it may only be an approximation for mean values, and for some (like heat capacities) it may be decided by experiments [11]. We applied three univariate statistical tests in the analysis.…”