Lipopolysaccharide nanoparticles: A biomimetic platform to study bacterial surface

Lipopolysaccharides (LPSs) are essential components of the outer membranes of gram-negative bacteria, playing a crucial role in antimicrobial resistance, virulence, and the host's immune response. Self-assembled particles displaying LPSs are essential for biophysical studies addressing the behavior of bacterial surfaces under specific biomimetic conditions. Styrene-maleic acid copolymers were employed to form LPS nanoparticles, either from extracted LPS or directly from purified outer membranes. These nanoparticles, derived from pathogenic O157:H7 or laboratory Escherichia coli strains, are well-defined in size and yield high-resolution nuclear magnetic resonance spectra. They have been successfully used to investigate molecular recognition by a human C-type lectin receptor of the immune system and interaction with polymyxin antibiotics using various biophysical methods. This study highlights the significance of LPS nanoparticles as bacterial surface mimetics and opens promising avenues for further research into LPS structure and interactions. The ability to generate well-defined LPS nanoparticles offers a powerful tool for studying the molecular mechanisms underlying bacterial pathogenesis and immune response.