PoreDesigner for tuning solute selectivity in a robust and highly permeable outer membrane pore.

Area of Science:

• Biomimetic Materials Science
• Membrane Separation Technology
• Computational Protein Design

Background:

• Angstrom-size pores in synthetic membranes offer energy-efficient separations but are challenging to engineer.
• Biological membrane proteins, like aquaporins, provide selective transport but have limitations in synthetic applications.
• Current synthetic membranes often lack tunable selectivity and high permeability.

Purpose of the Study:

• To develop a computational design workflow, PoreDesigner, for creating synthetic angstrom-size pores.
• To redesign Outer Membrane Protein F as a scaffold for tunable, highly selective pores.
• To achieve separation capabilities for small molecules and salts with high water permeability.

Main Methods:

• Utilized a beta-barrel Outer Membrane Protein F scaffold for pore redesign.
• Employed the PoreDesigner workflow to specify pore size (3-10 Å), profile, and chemistry.
• Designed three distinct pore variants targeting specific molecular weight cutoffs (>360 Da, >180 Da, >58 Da).

Main Results:

• Successfully designed three specific pore structures with exclusion limits for sucrose, glucose, and salt.
• Demonstrated the ability to engineer pore size and chemistry for precise molecular targeting.
• Achieved predicted water permeabilities exceeding aquaporins by over an order of magnitude.

Conclusions:

• PoreDesigner provides a versatile platform for creating high-performance synthetic separation membranes.
• Redesigned protein pores show potential for advanced water treatment and bioseparation applications.
• Engineered pores offer superior permeability and tunable selectivity compared to natural and existing synthetic channels.