A highly controllable protein self-assembly system with morphological versatility induced by reengineered host-guest...

Area of Science:

• Biomaterials Science
• Nanotechnology
• Protein Engineering

Background:

• Protein self-assembly into ordered nanostructures is crucial for biomaterials and understanding biological processes.
• Host-guest interactions, particularly with Cucurbit[8]uril (CB[8]) and Phe-Gly-Gly (FGG) tags, are used for artificial protein assembly.
• Existing FGG tags are genetically fused to N-termini, limiting their application in complex nanostructure construction.

Purpose of the Study:

• To overcome spatial limitations of current protein modification techniques for host-guest driven assembly.
• To develop a versatile, site-specific method for introducing binding tags onto protein surfaces.
• To enable the construction of sophisticated and dynamic protein-based nanosystems with diverse morphologies.

Main Methods:

• Design and synthesis of a maleimide-functionalized Phe-Gly-Gly (FGG) tag for site-specific protein modification.
• Utilizing the maleimide group for covalent attachment of the FGG tag to target proteins.
• Employing Cucurbit[8]uril (CB[8]) to mediate the self-assembly of modified proteins.

Main Results:

• Successful development of a versatile tool for site-specific protein modification with the CB[8]-binding FGG tag.
• Demonstration of controlled self-assembly of modified proteins mediated by CB[8].
• Achieved diverse nanostructure morphologies, including nanorings, nanospirals, nanowires, and superwires.

Conclusions:

• A novel strategy for site-specific protein modification using a functionalized FGG tag has been established.
• This approach expands the utility of the CB[8]/FGG system for creating complex protein nanostructures.
• The findings pave the way for designing 'smart' and dynamic self-assembling biomaterials.