Designing Two-Dimensional Protein Arrays through Fusion of Multimers and Interface Mutations

We have combined fusion of oligomers with cyclic symmetry and alanine substitutions to eliminate clashes and produce proteins that self-assemble into 2-D arrays upon addition of calcium ions. Using TEM, AFM, small-angle X-ray scattering, and fluorescence microscopy, we show that the designed lattices which are 5 nm high with p3 space group symmetry and 7.25 nm periodicity self-assemble into structures that can exceed 100 μm in characteristic length. The versatile strategy, experimental approach, and hexagonal arrays described herein should prove valuable for the engineering of functional nanostructured materials in 2-D.