Using neutron reflectivity from monolayer models of bacterial cell membranes to understand the interaction with an antimicrobial peptide

Antimicrobial peptides are being investigated as an alternative to antibiotics, as bacteria seem less able to acquire resistance to them. We have been investigating the way in which these peptides interact with models for the membranes that enclose bacteria. Bacteria have two membranes and the outer one is decorated by long chain sugar molecules, which extend away from the bacteria. We have learnt how to anchor these molecules at the air/water interface and have used the reflection of neutrons from this interface to study the layer structure. In this experiment we will study how much antimicrobial peptide interacts with this first layer of defence at the periphery of the bacteria and how it changes the layer structure. We will also measure the initial interaction of the peptide with a model for the inner bacterial membrane. This will help us understand how the peptides kill bacteria.