Solvation thermodynamics of nonionic solutes
TL;DR: In this paper, a generalized process of solvation is defined, and it is argued that the thermodynamics of this solvation process is more informative as compared with other processes suggested before, and numerical examples are presented and compared with some recently published related data.
Abstract: A generalized process of solvation is defined. It is argued that the thermodynamics of this solvation process is more informative as compared with other processes suggested before. Numerical examples are presented and compared with some recently published related data.
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TL;DR: It is demonstrated in this work that the surface tension, water‐organic solvent, transfer‐free energies and the thermodynamics of melting of linear alkanes provide fundamental insights into the nonpolar driving forces for protein folding and protein binding reactions.
Abstract: We demonstrate in this work that the surface tension, water-organic solvent, transfer-free energies and the thermodynamics of melting of linear alkanes provide fundamental insights into the nonpolar driving forces for protein folding and protein binding reactions. We first develop a model for the curvature dependence of the hydrophobic effect and find that the macroscopic concept of interfacial free energy is applicable at the molecular level. Application of a well-known relationship involving surface tension and adhesion energies reveals that dispersion forces play little or no net role in hydrophobic interactions; rather, the standard model of disruption of water structure (entropically driven at 25 degrees C) is correct. The hydrophobic interaction is found, in agreement with the classical picture, to provide a major driving force for protein folding. Analysis of the melting behavior of hydrocarbons reveals that close packing of the protein interior makes only a small free energy contribution to folding because the enthalpic gain resulting from increased dispersion interactions (relative to the liquid) is countered by the freezing of side chain motion. The identical effect should occur in association reactions, which may provide an enormous simplification in the evaluation of binding energies. Protein binding reactions, even between nearly planar or concave/convex interfaces, are found to have effective hydrophobicities considerably smaller than the prediction based on macroscopic surface tension. This is due to the formation of a concave collar region that usually accompanies complex formation. This effect may preclude the formation of complexes between convex surfaces.
5,295 citations
TL;DR: A major revival in the use of classical electrostatics as an approach to the study of charged and polar molecules in aqueous solution has been made possible through the development of fast numerical and computational methods to solve the Poisson-Boltzmann equation for solute molecules that have complex shapes and charge distributions.
Abstract: A major revival in the use of classical electrostatics as an approach to the study of charged and polar molecules in aqueous solution has been made possible through the development of fast numerical and computational methods to solve the Poisson-Boltzmann equation for solute molecules that have complex shapes and charge distributions. Graphical visualization of the calculated electrostatic potentials generated by proteins and nucleic acids has revealed insights into the role of electrostatic interactions in a wide range of biological phenomena. Classical electrostatics has also proved to be successful quantitative tool yielding accurate descriptions of electrical potentials, diffusion limited processes, pH-dependent properties of proteins, ionic strength-dependent phenomena, and the solvation free energies of organic molecules.
2,740 citations
2,088 citations
TL;DR: In this paper, the standard molar Gibbs free energies of hydration, ΔhydG°, of 109 (mainly inorganic) ions ranging in their charges from −3 to +4 have been compiled and interpreted in terms of a model used previously for other thermodynamic quantities.
Abstract: The standard molar Gibbs free energies of hydration, ΔhydG°, of 109 (mainly inorganic) ions ranging in their charges from –3 to +4 have been compiled and interpreted in terms of a model used previously for other thermodynamic quantities of hydration. The main contributions to ΔhydG° are the electrostatic effects, resulting in solvent immobilization, electrostriction, and dielectric saturation in a hydration shell of specified thickness, and further such effects on the water that surrounds this shell. Other effects contribute to ΔhydG° to a minor extent only.
1,574 citations
TL;DR: This chapter summarizes the experimental information on protein energetics and investigates the correlation between thermodynamic and structural characteristics of protein, including the water-ASA of various groups in the native and unfolded states, the number of hydrogen bonds, and the extent of van der Waals contacts in thenative state.
Abstract: Publisher Summary This chapter summarizes the experimental information on protein energetics. This field is developing fast and the concept of the energetics of protein structure has changed considerably during the past few years based on new findings. The proteins which are presented in the chapter are selected from a large number of proteins for which the thermodynamics of unfolding are studied in laboratory. The analysis of protein energetics presented in this chapter is based on several assumptions: (1) protein groups contribute additively, and proportionally as their surfaces, to the overall thermodynamic effects of unfolding; (2) the protein interior closely resembles an organic crystal in the way groups are packed and the energetics of the interactions among these groups are similar to those in the organic crystals; and (3) under certain conditions the denatured protein can be regarded as unfolded. The main criteria in choosing these proteins have been the reversibility of the denaturation process modeling unfolding, the completeness of this unfolding, the reliability of thermodynamic data on this process, and the resolution of the three dimensional structure of the given protein. The latter is important to investigate the correlation between thermodynamic and structural characteristics of protein, including the water-ASA of various groups in the native and unfolded states, the number of hydrogen bonds, and the extent of van der Waals contacts in the native state.
998 citations
References
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Book•
01 Aug 1991
TL;DR: In this article, the authors discuss the properties of water molecules and their relationship with common soluble proteins, such as membrane proteins and membrane membrane proteins, as well as the effect of temperature on their properties.
Abstract: The Solubility of Hydrocarbons in Water. Solubility of Amphiphiles in Water and Organic Solvents. The Effect of Temperature: Anomalous Entropy and Heat Capacity. The Structure of Water. Micelles: Introduction. Thermodynamics of Micelle Formation. Micelle Size and Shape. Mixed Micelles. Monolayers. Biological Lipids. Motility and Order. Proteins: Hydrophobic Side Chains and Conformational Change. The Association of Hydrocarbons and Amphiphiles with Common Soluble Proteins. Serum Lipoproteins. Biological Membranes. Membrane Proteins. Author and Subject Indices.
3,358 citations
1,663 citations
TL;DR: A survey of the published values of heat capacity and enthalpy obtained from calorimetric measurements on the crystal, glass, and liquid phases of the first few members of homologous series expressed as polynomial functions of temperature were fit to selected data by a least squares procedure as mentioned in this paper.
Abstract: A survey of the published values of heat capacity and enthalpy obtained from calorimetric measurements on the crystal, glass, and liquid phases of the first few members of homologous series expressed as polynomial functions of temperature were fit to selected data by a least squares procedure. Tables of smoothed values of thermodynamic properties, derived from these functions, are presented for 38 compounds.
1,019 citations