Date : 27/01/2010

Laboratory

Laboratoire de Physique Statistique de l'ENS UMR CNRS 8550
24 rue Lhomond 75005 Paris
Director : E. Perez

PhD Supervisor
Wladimir Urbach
email : This e-mail address is being protected from spam bots, you need JavaScript enabled to view it
phone : +33 688580978

Subjects / Tools-Methodologies
1 : interaction of trasmembrane protein/Fluorescence recovery after pattern photobleaching
2 : efflux pump activity/micromanipulation of giant unilamelar vesicles
3 : biomimetic systems/microscopy and Small angle scattering

Web : http://www.lps.ens.fr/spip.php?rubrique34

Available funding from ANR

Summary of lab's interests

In Statistical Physics Laboratory of the ENS, the diversity of research subjects (experimental and theoretical) is cite important. It ranges from fundamental physics to biophysics. Those interested can visit the Web page of LPS: http://www.lps.ens.fr/spip.php?rubrique34

Summary of project

Some bacteria control the intracellular concentration of various substrates (antibiotics, heavy metals) in organizing their expulsion through efflux pumps whose modus operandi are unknown. With these pumps, inserted in their dual - membrane, bacteria can become resistant to antibiotics. Understanding how they work would determine how to block them and thus reduce the resistance. These pumps are made of three parts: one in the outer membrane, the other in the inner membrane, and a third is located between two membranes of the bacteria. The project aims to reconstruct a pump in an artificial double bilayer system, which we have shown to be biologically relevant by demonstrating activity of several transmembrane proteins in this system. The production of all three parts of the pump is now under control:
1) Measurements on individual links between the different parties to understand the stability of the whole.
2) Reconstruction of the pump in vitro. This reconstruction will be done by inserting the parties in membrane vesicles of lipid membranes, and observing the passage of fluorescent molecules from one vesicle to another.