Prof. Pavel Jungwirth
Friday, March 15th at 3:30 pm Seminar Title: “Charge Scaling as a “Free Lunch“ Mean-Field Approach to Electronic Polarization in Aqueous Solutions”
Abstract:
Electrical stimuli are essential for a plethora of biological functions. Unlike in electronics, where electrons form currents, nature rather exploits ions as charge carriers. Lack of a consistent molecular picture of action of ions impairs progress in fundamental understanding of ion-controlled biological processes and in designing smart strategies for fixing ion-related pathological conditions. Molecular simulations represent a powerful tool for modelling such processes, however, they can only be as good as is the underlying interaction model (force field). A major drawback of commonly used force fields is the lack of description of electronic polarization, which results in severe artefacts such as a dramatic over-binding of ions, preventing, e.g., accurate modelling of calcium signaling processes. This now well-recognized deficiency hampers faithful modelling of complex ion-involving biological processes.
In our work, we employ machine learning techniques to build a de novo comprehensive force field for biological systems, that accounts for electronic polarization in a mean field way via charge scaling. This approach will qualitatively improve modelling of ions in biological contexts without additional computational costs. This will allow us to address accurately highly relevant ion-specific processes of increasing complexity from molecular over cellular to organ levels. In this lecture, I will primarily report on our progress so far, focusing in particular on charge scaling models for water and biologically relevant ions.
Faculty Host: Gil Nathanson