Dr. Charlotte Bouquiaux - Namur, Belgique

Le 13 novembre 2023

Le lundi 13 novembre à 11h00 dans l'amphi L003, le Dr. Charlotte Bouquiaux du laboratoire LTC de l’Université de Namur, Belgique, donnera une conférence intitulée :

Multi-Scale Theoretical Investigation of the Linear and Nonlinear Optical Responses of Di-8-ANEPPS Embedded in Complex Environments: on the Way to Explore the Complexity of Cell Membranes.

Abstract:

The aim of this work is to assess the effects of the environment on the nonlinear optical (NLO) responses of the di-8-ANEPPS chromophore embedded in lipid bilayers by using newly-optimized theoretical chemistry methods. Due to the enormous complexity of cell membranes, the strategy is to decompose the chemical diversity found in a plasma membrane (PM) into several one-component lipid bilayers, allowing to disentangle the effects of each lipid species. Starting from a pure DPPC bilayer, collections of systems varying either in the nature of the polar head or in the fatty acids were considered, showing that changes in the hydrophobic head modulate the NLO responses more than the variations in the hydrocarbon core. Mixed systems were then introduced by adding cholesterol molecules at different concentrations in DPPC bilayers, highlighting the condensing effect of cholesterol, inducing an increase in NLO responses. Finally, the system complexity was taken to a new level with the study of a multi-million atom PM. It showcases what is now possible to do in terms of computational resources and emphasizes the appeal of data mining tools in such complex investigations.