Theory of mechanochemical phenomena in molecular and biomolecular systems

University Of Texas At Austin, Austin TX

Investigators

Abstract

Dmitrii Makarov of the University of Texas at Austin is supported by an award from the Chemical Theory, Models and Computational Methods program in the Chemistry Division to study the interplay between chemical and mechanical forces in biological and artificial molecules. Makarov and coworkers develop theoretical and computational tools for predicting whether (and how) pulling or squeezing molecules accelerates or suppresses chemical processes. Biological molecular machines use the energy of chemical reactions to perform a myriad of mechanical tasks, through which they, for example, transport cargo across cells, make human hearts beat, defend cells against diseases, and make new molecules. Conversely, chemists have recently learned how to induce unusual chemical transformations by pulling or pushing on molecules, opening up the possibility of designing smart materials that change their properties when subjected to mechanical forces. Toward understanding and utilizing these phenomena, Makarov and his research group also develop techniques allowing experimenters to monitor molecular motion by measuring the tiny mechanical forces they create. Graduate and undergraduate students are involved in this research project. The research supported by this grant includes two major components. First, methods are being developed for the efficient computation of the rates of mechanochemical transformations. The specific challenges are to predict how reaction mechanisms change in response to mechanical perturbations and to search for novel mechanosensitive molecules ("mechanophores") that allow, for example, breaking strong chemical bonds with weak forces, mechanically-induced strengthening of bonds, and mechanically-activated release of small molecules. Second, the Makarov group is developing theoretical tools for the analysis of single-molecule force spectroscopy measurements, with a focus on theoretical characterization of experimentally-observed transition-path ensembles in biomolecular folding.