Lipids do influence protein function-the hydrophobic matching hypothesis revisited.

Area of Science:

• Membrane Biophysics
• Structural Biology
• Computational Biology

Background:

• Integral membrane proteins and lipid bilayers dynamically interact.
• Previous models focused on protein influence on lipids; recent data show reciprocal effects.
• Key physical concepts include hydrophobic matching and curvature stress.

Purpose of the Study:

• To review current understanding of lipid-protein physical interactions in membranes.
• To re-evaluate hydrophobic matching and curvature stress in light of new data.
• To explore the influence of lipid physical state on integral protein function using aquaporin GlpF as a model.

Main Methods:

• Topical review of experimental and theoretical studies.
• Detailed case study of aquaporin GlpF (a trans-membrane water-channel protein).
• Molecular Dynamics (MD) simulations to analyze lipid-bilayer and protein interactions.

Main Results:

• Lipid bilayers adapt to integral proteins via hydrophobic matching, favoring curved structures.
• The physical state of lipids, including matching and curvature stress, actively modulates protein function.
• Aquaporin GlpF's transport function is shown to be lipid-specifically modulated by these membrane properties.

Conclusions:

• Lipid-protein interactions are a two-way street, with lipids actively shaping protein behavior.
• Hydrophobic matching and curvature stress are critical physical parameters influencing membrane protein function.
• Understanding these interactions is key to deciphering biological membrane processes.