Emerging Roles of Air Gases in Lipid Bilayers.

Area of Science:

• Biophysics
• Materials Science
• Biochemistry

Background:

• Membrane protein function is sensitive to the physical properties of lipid bilayers.
• Dissolved gases in lipid bilayers are often overlooked but can influence their behavior.

Purpose of the Study:

• To investigate the effects of dissolved nitrogen and oxygen on the mechanical properties and stability of lipid bilayers.
• To understand how dissolved gases influence lipid bilayer phase separation and rigidity.

Main Methods:

• Differential confocal microscopy
• Atomic force microscopy
• Molecular dynamics simulations

Main Results:

• Lipid bilayers in degassed solutions are softer and less stable than those in ambient solutions.
• High nitrogen concentrations increase bending moduli and stability, impeding phase separation.
• Molecular dynamics simulations reveal higher nitrogen affinity contributes to increased lipid bilayer rigidity.

Conclusions:

• Dissolved air gases, particularly nitrogen, significantly alter lipid bilayer mechanical properties and stability.
• These findings have broad implications for understanding cell membrane behavior and the origin of life.