caa a22 4500 463191501 CHVBK 20180406164910.0 cr unu---uuuuu 170326e20070901xx s 000 0 eng 10.1007/s10973-007-8464-2 doi (NATIONALLICENCE)springer-10.1007/s10973-007-8464-2 Kustov A. United Physico-Chemical Center of Solutions of Institute of Solution Chemistry and Ivanovo State University of Chemistry and Technology, Russian Academy of Sciences, 1 Academicheskaya str., 153045, Ivanovo, Russia aut The aromatic amino acid behaviour in aqueous amide solutions [Elektronische Daten] The temperature dependence of the L -phenylalanine-urea interaction [A. Kustov] The enthalpies of solution of L-phenylalanine in the mixtures of water with the protein denaturant urea have been measured in the temperature range of 288.15-318.15 K. Using the results of the present research and literature data of free energies, the standard thermodynamic functions of the solute transfer from water to aqueous urea solutions have been estimated in a wide temperature range. The enthalpic, heat capacity, entropic and free energy parameters of the solute-urea pair and triplet interactions have been computed. The amino acid — amide pair interaction was found to be attractive in the temperature range studied due to the favourable enthalpic term. The triplet interaction being slightly repulsive reveals the enthalpic origin also. The examination of the Savage and Wood additivity-of-groups approach does indicate the inapplicability of this scheme to enthalpies and entropies of interaction. It has been found for the first time that the heat capacity of interaction changes its sign at 303 K, i.e. the temperature dependence of enthalpic and entropic parameters passes through the pronounced extrema near the temperature of the minimum of the heat capacity of pure water. Springer Science+Business Media LLC, 2007 amino acids nationallicence denaturant aqueous solutions nationallicence enthalpy of solution nationallicence L-phenylalanine-urea interaction nationallicence Journal of Thermal Analysis and Calorimetry Springer US; http://www.springer-ny.com 89/3(2007-09-01), 841-846 1388-6150 89:3<841 2007 89 10973 https://doi.org/10.1007/s10973-007-8464-2 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s10973-007-8464-2 text/html Onlinezugriff via DOI NATIONALLICENCE 100 1- Kustov A. United Physico-Chemical Center of Solutions of Institute of Solution Chemistry and Ivanovo State University of Chemistry and Technology, Russian Academy of Sciences, 1 Academicheskaya str., 153045, Ivanovo, Russia aut NATIONALLICENCE 773 0- Journal of Thermal Analysis and Calorimetry Springer US; http://www.springer-ny.com 89/3(2007-09-01), 841-846 1388-6150 89:3<841 2007 89 10973 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer