title: Thermodynamic signatures in macromolecular interactions involving conformational flexibility.
abstract: The energetics of macromolecular interactions are complex, particularly where protein flexibility is involved. Exploiting serendipitous differences in the plasticity of a series of closely related trypsin variants, we analyzed the enthalpic and entropic contributions accompanying interaction with L45K-eglin C. Binding of the four variants show significant differences in released heat, although the affinities vary little, in accordance with the principle of enthalpy-entropy compensation. Binding of the most disordered variant is almost entirely enthalpically driven, with practically no entropy change. As structures of the complexes reveal negligible differences in protein-inhibitor contacts, we conclude that solvent effects contribute significantly to binding affinities.
authors.forename: Anja
authors.initials: A
authors.lastname: Menzel
authors.forename: Piotr
authors.initials: P
authors.lastname: Neumann
authors.forename: Christian
authors.initials: C
authors.lastname: Schwieger
authors.forename: Milton T
authors.initials: MT
authors.lastname: Stubbs
mesh_terms: D018360:Crystallography, X-Ray; D006860:Hydrogen Bonding; D046911:Macromolecular Substances / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D018583:Pliability; D013816:Thermodynamics
chemical_list: D046911:Macromolecular Substances