Control of Superselectivity by Crowding in Three-Dimensional Hosts.

Area of Science:

• Biophysics
• Soft Matter Physics
• Systems Biology

Background:

• Membraneless organelles exhibit precise molecular composition.
• Superselective binding is known at surfaces but less understood in 3D cellular environments.
• Understanding binding transitions is key to cellular function and biomaterial design.

Purpose of the Study:

• Investigate sharp binding-unbinding transitions of multivalent molecules with receptors in 3D porous structures.
• Determine the role of molecular crowding in achieving superselectivity within these 3D environments.
• Explore the robustness of superselective binding under varying molecular and interaction parameters.

Main Methods:

• Utilized Monte Carlo simulations.
• Employed an archetypal lattice polymer model.
• Simulated multivalent client molecules interacting with receptors in a 3D porous structure.

Main Results:

• Identified that molecular crowding significantly enhances or introduces superselectivity in 3D.
• Observed that crowding initially imposes an entropic penalty, followed by facilitated simultaneous bond formation.
• Demonstrated robust superselective behavior across variations in client valency, linker length, and binding interactions.

Conclusions:

• Molecular crowding is a critical factor for achieving superselectivity in 3D binding systems.
• The findings provide insights into the mechanisms governing compositional control in membraneless organelles.
• This work has implications for the design of artificial cellular compartments and targeted molecular assembly.