Speaker
Description
Gram-negative bacteria are surrounded by a protective outer membrane with phospholipids in its inner leaflet and lipopolysaccharides (LPS) in its outer leaflet. The outer membrane is also populated with many β-barrel outer-membrane proteins (OMPs), some of which have been shown to cluster into supramolecular assemblies. Using atomic force microscopy on living bacteria, we have shown that the outer membrane of E. coli is phase-separated into LPS-enriched and OMP-enriched domains, and that additional phases appear when the LPS-phospholipid asymmetry of the outer membrane is perturbed. I will discuss how we have discovered and characterised these phases, and conclude with an outlook how studies of nanoscale in-plane membrane heterogeneity may be complemented by neutron reflectometry for studying out-of-plane order in the membrane.
