Biomimetic Vesicles with Designer Phospholipids Can Sense Environmental Redox Cues

• Published in: JACS Au 2024-05, Vol.4 (5), p.1841-1853
• Main Authors: Erguven, Huseyin, Wang, Liming, Gutierrez, Bryan, Beaven, Andrew H., Sodt, Alexander J., Izgu, Enver Cagri
• Format: Article
• Language: English
• ISSN: 2691-3704; 2691-3704
• DOI: 10.1021/jacsau.4c00041

Cell-like materials that sense environmental cues can serve as next-generation biosensors and help advance the understanding of intercellular communication. Currently, bottom-up engineering of protocell models from molecular building blocks remains a grand challenge chemists face. Herein, we describe giant unilamellar vesicles (GUVs) with biomimetic lipid membranes capable of sensing environmental redox cues. The GUVs employ activity-based sensing through designer phospholipids that are fluorescently activated in response to specific reductive (hydrogen sulfide) or oxidative (hydrogen peroxide) conditions. These synthetic phospholipids are derived from 1,2-dipalmitoyl-rac-glycero-3-phosphocholine and they possess a headgroup with heterocyclic aromatic motifs. Despite their structural deviation from the phosphocholine headgroup, the designer phospholipids (0.5–1.0 mol %) mixed with natural lipids can vesiculate, and the resulting GUVs (7–20 μm in diameter) remain intact over the course of redox sensing. All-atom molecular dynamics simulations gave insight into how these lipids are positioned within the hydrophobic core of the membrane bilayer and at the membrane–water interface. This work provides a purely chemical method to investigate potential redox signaling and opens up new design opportunities for soft materials that mimic protocells.