Thermodynamics Of The Interaction Of Amino Acids And Polyols

Amino acids,which have been used extensively as the most important biological model compounds, are not only the basic building blocks of proteins, but also the important active materials in living things. Sugars and polyols help in stabilizing the native conformation of globular proteins. There has been significant interest in the investigation on the interaction in aqueous solutions between amino acids and organic molecules present in living organisms or possessing functional group identical. The principle reasons for studying such systems are to obtain the information that contributes to the growing body of knowledge about solute solvation and solute-solute interactions in aqueous media, and a better understanding of their role played in the conformational stability and unfolding behavior of proteins.This paper mainly consists of the following five parts.The first part summarizes the general states of studies on the thermodynamic properties of systems containing protein model molecules.In the second part, enthalpies of mixing of aqueous amino acids solutions (glycine, L-alanine, L-serine, L-valine, L-proline, L-threonine) with aqueous polyols solutions (mannitol, inositol) have been determined at 298.15K by 2277 flow microcalorimetric system. These results along with enthalpies of dilution of these aqueous solutions have been used to obtain the enthalpic interaction coefficients (h_xy, h_xxy, h_xyy) in terms of the McMillan-Mayer theory. The pairwise interactions between amino acids and polyols have been discussed by solute-solute interaction theory.In the third part, the enthalpic pairwise interactions between six kinds of amino acids and saccharides (xylose, galactose) have been determined at 310.15K.In the forth part, the heterotactic enthalpic pairwise interaction coefficients between amino acids and butanediol isomers (1,3-butanediol, 1,4-butanediol and 2,3-butanediol) at 298.15K and 310.15K are discussed. The change of temperature made remarkable effects on the values of h_xy. The interaction...