Effect of cations on bacterial lipopolysaccharides (LPS) self-assembled structures

Lipopolysaccharides (LPS) is a key structural component of the outer membrane of gram-negative bacteria. LPS can trigger lethal septic shocks when released into a host’s bloodstream (i.e. the endotoxic effect). Cations can complex with LPS and lead to LPS aggregates structure transformation, which affects bacterial membrane integrity and LPS virulence. Here, we propose a small-angle neutron scattering study (SANS) of self-assembled structures formed by different LPS chemotypes in solutions of different cations at near physiological conditions. We will vary the cation valency (comparing monovalent (Na+), divalent (Ca2+) and multivalent cations (La3+)), as well as the LPS architecture, i.e. its carbohydrate head group length (LPS-smooth, LPS-Ra and LPS-Rd). We also propose to investigate the temperature effect on these systems.