Distance tuneable integral membrane protein containing floating bilayers via in situ directed self-assembly

Area of Science:

• Biophysics
• Membrane Biochemistry
• Structural Biology

Background:

• Model membranes are crucial for studying membrane biochemistry but often lack biological accuracy due to reduced complexity.
• Floating supported bilayers offer enhanced accuracy by creating planar lipid membranes not adhered to a surface.

Purpose of the Study:

• To incorporate the integral membrane protein complex, the multidomain β-barrel assembly machinery (Bam), into *in situ* self-assembled floating supported bilayers.
• To demonstrate the fabrication, complexity, and tuneability of this novel membrane assay system.

Main Methods:

• Utilized a two-step self-assembly process for fabricating the floating supported bilayers.
• Employed neutron reflectometry and quartz crystal microbalance measurements for characterization.
• Investigated membrane-to-surface distance tuneability by altering bulk solution salt concentration.

Main Results:

• Successfully incorporated the multidomain β-barrel assembly machinery (Bam) into the floating supported bilayers.
• Demonstrated the system's fabrication via a two-step self-assembly process.
• Showcased tuneable membrane-to-surface distances by adjusting salt concentration.

Conclusions:

• Developed an easily fabricated, biologically accurate, and tuneable membrane assay system.
• The system is suitable for studying integral membrane proteins within their native lipid environment.
• This advancement offers improved accuracy for molecular-level biophysical studies.