Microcalorimetric titrations of calmodulin with Ca" and trifluoperazine (TFP) at various molar ratios have been carried out at 25 "C and at pH 7.0. Ca2+ binding to calmodulin produces heat ( A H ) in the presence of TFP, while heat is absorbed in the absence of TFP. The total heat produced by Ca2+ binding to all four sites is increased at increasing TFP-to-calmodulin ratios, attaining a plateau...

The development of HIV-1 protease inhibitors has been the historic paradigm of rational structure-based drug design, where structural and thermodynamic analyses have assisted in the discovery of novel inhibitors. While the total enthalpy and entropy change upon binding determine the affinity, often the thermodynamics are considered in terms of inhibitor properties only. In the current study, pr...

The isothermal enthalpy changes with time of a dental composite were examined by microcalorimetry to isolate the effects of different filler concentrations and curing times on chemical aging of these composites. Urethane dimethacrylate (UDMA) monomer, zirconia-silica (ZS) powder, and 3-methacryloxypropyltrimethoxysilane (MAPM) were used as organic and inorganic matrices, and a coupling agent, r...

The thermodynamic functions such as enthalpy (H), Gibbs free energy (G) and entropy (S) of Serineand Threonine amino acids were theoretically studied at different condition (solvents andtemperatures) by using Gussian o3, software. First, the structural optimization of isolated Serine andThreonine were done in the gas phase by using the Hartree-Fock (HF) level of theory with 3-21G, 6-31G and 6-3...

Nonstoichiometric metal oxides with variable valence are attractive redox materials for thermochemical and electrochemical fuel processing. To guide the design of advanced redox materials for solar-driven splitting of CO2 and/or H2O to produce CO and/or H2 (syngas), we investigate the equilibrium thermodynamics of the LaxSr1 xMnyAl1 yO3 d perovskite family (0 # x # 1, 0 # y # 1) and La0.6Ca0.4M...

Microcalorimetric titrations of calmodulin with Ca2+ and trifluoperazine (TFP) at various molar ratios have been carried out at 25 degrees C and at pH 7.0. Ca2+ binding to calmodulin produces heat (-delta H) in the presence of TFP, while heat is absorbed in the absence of TFP. The total heat produced by Ca2+ binding to all four sites is increased at increasing TFP-to-calmodulin ratios, attainin...

Linker histones (H1) are the basic proteins in higher eukaryotes that are responsible for the final condensation of chromatin. In contrast to the nucleosome core histone proteins, the role of H1 in compacting DNA is not clearly understood. In this study ITC was used to measure the binding constant, enthalpy change, and binding site size for the interactions of H10, or its C-terminal (H10-C) and...

High-energy phosphate metabolism and energy liberated as heat and work were measured in 3-s tetani of frog sartorius muscle at 0°C. Two contraction periods were studied: (a) a 0.35-s period of shortening near halfmaximum velocity beginning after 2 s of isometric stimulation, and (b) a 0.65-s isometric period immediately following the shortening. There were no significant changes in levels of AT...

Titration calorimetry measurements on the binding of hen lysozyme to the specific monoclonal IgG antibodies D1.3, D11.15, D44.1, F9.13.7, F10.6.6, their papain-cleaved antigen binding fragments (Fab) and their protein-engineered fragments consisting of non-covalently linked heavy variable chain and light variable chain domains (Fv) were performed between 6-50 degrees C in 0.15 M NaCl, 0.01 M so...