Self-Assembling 2D Arrays with de Novo Protein Building Blocks

Area of Science:

• Protein engineering and structural biology
• Biomolecular self-assembly and nanotechnology

Background:

• Modular self-assembly of DNA into 2D arrays is well-established.
• Achieving similar modularity and specificity with proteins for 2D array formation has been challenging.
• The lack of protein-specific binding mechanisms analogous to DNA base pairing limits programmable protein assembly.

Purpose of the Study:

• To develop a general method for designing 2D protein arrays using de novo designed building blocks.
• To overcome the limitations of protein specificity in programmable self-assembly.
• To create protein building blocks capable of forming ordered 2D lattices.

Main Methods:

• Designed pseudosymmetric protein building blocks from a homodimeric helical bundle.
• Utilized Rosetta software for surface redesign to promote self-assembly into a C12 layer symmetry group.
• Verified assembly and lattice geometry using negative stain electron microscopy and atomic force microscopy.

Main Results:

• Two out of ten designed protein arrays successfully assembled to micrometer scale.
• Observed designed lattice geometry in assembled protein arrays.
• Achieved assembly sizes up to 100 nm, demonstrating controlled protein self-assembly.

Conclusions:

• Demonstrated a viable strategy for designing 2D protein arrays using pseudosymmetric building blocks.
• This approach represents a significant advancement toward programmable protein self-assembly.
• Pseudosymmetric patterning of orthogonal binding interfaces offers a pathway for precise control over protein assembly.