Vesicle fusion with bilayer lipid membrane controlled by electrostatic interaction

Area of Science:

• Biophysics
• Materials Science
• Membrane Biology

Background:

• Proteoliposome fusion is key for integrating membrane proteins into artificial lipid bilayers.
• Controlling vesicle fusion is essential for precise functionalization of supported bilayer lipid membranes (s-BLMs).

Purpose of the Study:

• To develop a method for controlled vesicle fusion with s-BLMs using electrostatic interactions.
• To investigate the influence of lipid charge and concentration on vesicle fusion dynamics.

Main Methods:

• Utilized anionic large unilamellar vesicles (LUVs) and cationic s-BLMs to establish electrostatic attraction.
• Controlled fusion by adjusting the concentration of cationic lipids in the s-BLMs.
• Assessed fusion efficiency and s-BLM fluidity post-fusion.

Main Results:

• Anionic LUVs selectively fused with cationic s-BLMs, avoiding non-specific adsorption to SiO2 substrates.
• Vesicle fusion was precisely controlled by modulating cationic lipid concentration, leading to saturation.
• Post-fusion s-BLMs maintained high fluidity, indicating complete fusion with minimal intermediate states.

Conclusions:

• Electrostatic interactions provide a robust mechanism for controlling the position and quantity of vesicle fusion onto s-BLMs.
• This approach enables targeted incorporation of vesicle contents into artificial membranes.
• The method offers a pathway for creating functionalized artificial lipid membranes with high precision.