Séminaire Théorie

Mardi 25 Avril 2017 à 11h00.

The Unexpected Role of Ligand Number in Specific Ion Binding

''The binding of specific ions to proteins and synthetic materials plays a fundamental role in nerve cell signaling, water desalination, and battery function. Two distinct hypotheses have emerged to explain the preferential solvation of specific metal ions. One emphasizes the role of ligand chemistry, while another invokes hydration and Hofmeister sequences as key factors in determining specific ion-binding trends. We have developed a new approach to computing ion solvation free energies using quantum chemical tools, and used it to investigate the merits of each hypothesis. New insight arises from the finding that ion-binding sequences can be manipulated and even reversed by changing the number of ligands in a binding site. Our results help clarify the discrepancy in ion association between molecular ligands in aqueous solutions, and their chemical analogues in ion-channel binding sites.''