Redox- and metal-directed structural diversification in designed metalloprotein assemblies

Area of Science:

• Protein engineering
• Biophysical chemistry
• Materials science

Background:

• Designing protein building blocks for controlled self-assembly is crucial for creating novel biomaterials.
• Understanding the interplay of different interaction types (hydrophobic, metal-ligand, covalent) is key to predicting and controlling protein assembly.

Purpose of the Study:

• To design and characterize a protein building block with dual gating mechanisms for self-assembly.
• To demonstrate the ability of a single protein construct to form multiple, distinct oligomeric states.
• To explore the use of redox state and metal ion identity as external triggers for protein architecture control.

Main Methods:

• Protein design and synthesis.
• Structural characterization (e.g., X-ray crystallography, NMR spectroscopy).
• Biophysical characterization (e.g., dynamic light scattering, isothermal titration calorimetry).

Main Results:

• A designed protein building block was created with self-assembly controlled by disulfide bond redox state and metal ion identity.
• The protein construct was shown to access five distinct oligomeric states.
• Extensive structural and biophysical data confirmed the responsive nature of the protein architectures.

Conclusions:

• A single protein building block can yield multiple, responsive architectures by harnessing combined interaction types.
• Dual gating mechanisms (redox and metal ions) offer precise control over protein self-assembly.
• This work provides a framework for designing complex, stimulus-responsive protein-based materials.