title: Volume of Hsp90 Protein-Ligand Binding Determined by Fluorescent Pressure Shift Assay, Densitometry, and NMR.
abstract: Human heat shock protein 90 (Hsp90) is a key player in the homeostasis of the proteome and plays a role in numerous diseases, such as cancer. For the design of Hsp90 ATPase activity inhibitors, it is important to understand the relationship between an inhibitor structure and its inhibition potential. The volume of inhibitor binding is one of the most important such parameters that are rarely being studied. Here, the volumes of binding of several ligands to recombinant Hsp90 were obtained by three independent experimental techniques: fluorescent pressure shift assay, vibrating tube densitometry, and high-pressure NMR. Within the error range, all techniques provided similar volumetric parameters for the investigated protein-ligand systems. Protein-ligand binding volumes were negative, suggesting that the protein-ligand complex, together with its hydration shell, occupies less volume than the separate constituents with their hydration shells. Binding volumes of tightly binding, subnanomolar ligands were significantly more negative than those of weakly binding, millimolar ligands. The volumes of binding could be useful for designing inhibitors with desired recognition properties and further development as drugs.
authors: Department of Biothermodynamics and Drug Design, Institute of Biotechnology, Vilnius University , Saulėtekio al. 7, LT-10257 Vilnius, Lithuania.
authors: Zigmantas
authors: Z
authors: Toleikis
authors: A.M. Butlerov Institute of Chemistry, Kazan Federal University , Kremlevskaya Street 18, Kazan 420008, Russia.
authors: Vladimir A
authors: VA
authors: Sirotkin
authors: Department of Biothermodynamics and Drug Design, Institute of Biotechnology, Vilnius University , Saulėtekio al. 7, LT-10257 Vilnius, Lithuania.
authors: Gediminas
authors: G
authors: Skvarnavičius
authors: Department of Biothermodynamics and Drug Design, Institute of Biotechnology, Vilnius University , Saulėtekio al. 7, LT-10257 Vilnius, Lithuania.
authors: Joana
authors: J
authors: Smirnovienė
authors: Centre de Biochimie Structurale, INSERM U1054, CNRS UMR 5048, Universités de Montpellier , 34000 Montpellier, France.
authors: Christian
authors: C
authors: Roumestand
authors: Department of Biothermodynamics and Drug Design, Institute of Biotechnology, Vilnius University , Saulėtekio al. 7, LT-10257 Vilnius, Lithuania.
authors: Daumantas
authors: D
authors: Matulis
authors: Department of Biothermodynamics and Drug Design, Institute of Biotechnology, Vilnius University , Saulėtekio al. 7, LT-10257 Vilnius, Lithuania.
authors: Vytautas
authors: V
authors: Petrauskas
mesh_terms: D000251:Adenosine Triphosphatases / Q000037:antagonists & inhibitors / Q000737:chemistry; D001665:Binding Sites / Q000187:drug effects; D003720:Densitometry; D004791:Enzyme Inhibitors / Q000737:chemistry* / Q000494:pharmacology; D005453:Fluorescence; D018841:HSP90 Heat-Shock Proteins / Q000037:antagonists & inhibitors / Q000737:chemistry*; D006801:Humans; D008024:Ligands; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D011312:Pressure
chemical_list: D004791:Enzyme Inhibitors; D018841:HSP90 Heat-Shock Proteins; D008024:Ligands; D000251:Adenosine Triphosphatases