In bacteria, mechanosensitive ion channels such as MscL protect cells against osmotic shock, but, as with all ion channels, they have the potential to act as an Achilles heel, by providing a target for antimicrobial treatments. It is thought that these work as pressure release valves and respond to an increase in membrane tension by opening. We will assemble planar tethered mimics of bacterial membranes using proteoliposomes prepared using cell-free expression of this ion channel. We will then challenge these membranes with an antimicrobial in an attempt to trigger the safety valves to open. The water that fills the pores in the open channels will change the neutron reflectivity of the layer, which we will measure in order to directly observe this triggering. The use of gold and magnetic spacer layers enhances our sensitivity to these small density changes in the lipid membrane.