The group has a longstanding interest in continuum electrostatics, targeted to applications in protein-protein interactions. The interactions of biomolecules are mediated by water, which is a highly polarizable medium. Due to the presence of ions and the charges of biomolecules, their properties are strongly affected by electrostatic forces. For large biomolecular systems, MD simulations are still time-consuming to perform over significant durations, so that often continuum electrostatics models are applied. These generally suffer from two shortcomings : the neglect of polarizability of the solvent medium, and the incapacity to treat electrostatic fluctuations, as the theories used are usually of mean-field type. In this field we have coordinated an ANR-funded project (2012-2016) :
Fluctuations in structured Coulomb fluids
We formed a consortium of four research groups attempting to improve the models and computational methods in the treatment of the above effects. The further consortium members were Dr. Anthony Maggs (ESPCI, Paris), Dr. Henri Orland (Saclay, Paris) and Prof. Ralf Everaers (ENS Lyon).
In our team, two lines of research were pursued in the context of this project. The first concerns the comparison of water solvent structure around proteins as predicted from MD simulations with data obtained from ‘structured’ continuum models. The second concerns fundamental theoretical results on the relation of structural and fluctuation effects in extended continuum models, applied to simple plate-like geometries. This allows us to obtain precise mathematical results, which are important to judge the quality of modeling as a prerequisite for the application of these models to more realistic biological systems.
In June 2015, we organized a workshop at ENS Lyon : http://fscf2015.sciencesconf.org