title: Experimental measurement of binding energy, selectivity, and allostery using fluctuation theorems.
abstract: Thermodynamic bulk measurements of binding reactions rely on the validity of the law of mass action and the assumption of a dilute solution. Yet, important biological systems such as allosteric ligand-receptor binding, macromolecular crowding, or misfolded molecules may not follow these assumptions and may require a particular reaction model. Here we introduce a fluctuation theorem for ligand binding and an experimental approach using single-molecule force spectroscopy to determine binding energies, selectivity, and allostery of nucleic acids and peptides in a model-independent fashion. A similar approach could be used for proteins. This work extends the use of fluctuation theorems beyond unimolecular folding reactions, bridging the thermodynamics of small systems and the basic laws of chemical equilibrium.
authors.affiliation: Small Biosystems Lab, Departament de Física de la Matèria Condensada, Facultat de Física, Universitat de Barcelona, Barcelona, Spain.|Centro de Investigación Biomédica en Red (CIBER) de Bioingeniería, Biomateriales y Nanomedicina, Instituto de Salud Carlos III, Madrid, Spain.
authors.forename: Joan
authors.initials: J
authors.lastname: Camunas-Soler
authors.affiliation: Small Biosystems Lab, Departament de Física de la Matèria Condensada, Facultat de Física, Universitat de Barcelona, Barcelona, Spain.|Centro de Investigación Biomédica en Red (CIBER) de Bioingeniería, Biomateriales y Nanomedicina, Instituto de Salud Carlos III, Madrid, Spain.
authors.forename: Anna
authors.initials: A
authors.lastname: Alemany
authors.affiliation: Small Biosystems Lab, Departament de Física de la Matèria Condensada, Facultat de Física, Universitat de Barcelona, Barcelona, Spain. fritort@gmail.com.|Centro de Investigación Biomédica en Red (CIBER) de Bioingeniería, Biomateriales y Nanomedicina, Instituto de Salud Carlos III, Madrid, Spain.
authors.forename: Felix
authors.initials: F
authors.lastname: Ritort
mesh_terms: D000494:Allosteric Regulation; D001665:Binding Sites; D004268:DNA-Binding Proteins / Q000737:chemistry*; D015246:Deoxyribonuclease EcoRI / Q000737:chemistry; D004448:Echinomycin / Q000737:chemistry; D008024:Ligands; D011485:Protein Binding; D000072760:Single Molecule Imaging; D013816:Thermodynamics
chemical_list: D004268:DNA-Binding Proteins; D008024:Ligands; D004448:Echinomycin; D015246:Deoxyribonuclease EcoRI