Intramolecular and Water Mediated Tautomerism of Solvated Glycine
Pengchao Zhang, Axel Tosello Gardini, Xuefei Xu, Michele Parrinello
Abstract
Understanding tautomerism and characterizing solvent effects on the dynamic processes pose significant challenges. Using enhanced-sampling molecular dynamics based on state-of-the-art deep learning potentials, we investigated the tautomeric equilibria of glycine in water. We observed that the tautomerism between neutral and zwitterionic glycine can occur through both intramolecular and intermolecular proton transfers. The latter proceeds involving a contact anionic-glycine-hydronium ion pair or separate cationic-glycine-hydroxide ion pair. These pathways with comparable barriers contribute almost equally to the reaction flux.
Topics & Concepts
TautomerIntramolecular forceChemistryGlycineIntermolecular forceHydroxideCationic polymerizationHydroniumProtonHydrogen bondSolventIonPhotochemistryComputational chemistryMoleculeStereochemistryInorganic chemistryOrganic chemistryAmino acidBiochemistryPhysicsQuantum mechanicsCrystallography and molecular interactionsProtein Structure and DynamicsSpectroscopy and Quantum Chemical Studies