Design of light- and chemically responsive protein assemblies through host-guest interactions.

Area of Science:

• Supramolecular Chemistry
• Protein Engineering
• Materials Science

Background:

• Host-guest interactions are crucial for developing dynamic materials and molecular machines due to their responsiveness and specificity.
• Protein assemblies offer potential for creating novel functional materials.

Purpose of the Study:

• To leverage host-guest chemistry for designing dynamic protein assemblies.
• To utilize a C4 symmetric protein, RhuA, as a building block for these assemblies.

Main Methods:

• Chemically modifying the C98RhuA protein with host (beta-cyclodextrin, βCD) and guest (azobenzene) functionalities.
• Observing the specific pairing of modified RhuA variants to form 1D and 2D assemblies.
• Investigating the control of assembly/disassembly using light (UV, visible) and small molecules.

Main Results:

• Successfully formed highly ordered 1D and 2D protein assemblies through specific host-guest pairing.
• Demonstrated light- and small-molecule-mediated control over assembly and disassembly dynamics.
• Discovered that the protein nanotubes assemble without a nucleation barrier, a rare characteristic for helical systems.

Conclusions:

• This study presents a novel strategy for creating complex, dynamic protein assemblies using host-guest chemistry.
• The findings highlight the potential of simple chemical modifications for achieving sophisticated structural and dynamic outcomes in protein engineering.