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arXiv · 1703.10346

Experimental measurement of binding energy, selectivity and allostery using fluctuation theorems

Joan Camunas-Soler·Anna Alemany·Felix Ritort
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Abstract

Thermodynamic bulk measurements of binding reactions critically 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 this fundamental law and 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, proteins and peptides in a model-independent fashion. 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.

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Joan Camunas-Soler, Anna Alemany, Felix Ritort. 2017-03-30. Experimental measurement of binding energy, selectivity and allostery using fluctuation theorems. https://doi.org/10.1126/science.aah4077

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