The Influence of Fluidity on Interactions with Models for the Bacterial Membrane
The increase in bacterial antibiotic resistance has led to a surge of interest in the physical properties of bacterial membranes and the way they interact with their environment. Antimicrobial peptides are an alternative to antibiotics and whose mode of action is thought to target bacterial membranes. AMPs typically exhibit an amphipathic alpha helical structure, which is also found in the bacterial membrane targeting sequence of the cell division protein, MinD. Neutron reflectivity from monolayers was used to try to understand the molecular details of the mechanism by which these peptides interact with and restructure membranes. The influence of lipid layer fluidity on these interactions was investigated through controlling the surface pressure. Whilst this action occurs within the cell, the presence of LPS on the exterior of the membrane can also have an influence on the fluidity, and on the uptake of AMPs. The structure of the O-antigen LPS chain under variable pressure, and its influence over the fluidity of the monolayer, was also measured.
This is a weekly series of informal talks given primarily by members of the soft condensed matter and statistical mechanics groups, but is also open to members of other groups and external visitors. The aim of the series is to promote discussion and learning of various topics at a level suitable to the broad background of the group. Everyone is welcome to attend..