<i>Salmonella</i> lipopolysaccharide‐containing supported lipid bilayers as platforms to study bacteriophage interactions

Lipopolysaccharides (LPS) are a key component in the defensive barrier of the outer membrane (OM) of Gram-negative bacteria; they are a major drug target and bacteriophage access point. Biomimetic platforms presenting LPS are therefore important to study OM biophysics of pathogens and initial bacteriophage infection steps. Herein, we present robust protocols for the preparation of LPS-containing supported lipid bilayers (SLBs) incorporating either Salmonella LPS or OM vesicles (OMVs). We characterized SLBs using quartz crystal microbalance with dissipation (QCM-D) and fluorescence microscopy. We probed their interactions with O-antigen specific Salmonella phages and their tailspike receptor binding proteins. Altogether, this work provides a roadmap to create versatile LPS-based platforms that facilitate studies of interactions between phages and Gram-negative bacterial membranes.