Designed and biologically active protein lattices

Versatile methods to organize proteins in space are required to enable complex biomaterials, engineered biomolecular scaffolds, cell-free biology, and hybrid nanoscale systems. Here, we demonstrate how the tailored encapsulation of proteins in DNA-based voxels can be combined with programmable assembly that directs these voxels into biologically functional protein arrays with prescribed and ordered two-dimensional (2D) and three-dimensional (3D) organizations. We apply the presented concept to ferritin, an iron storage protein, and its iron-free analog, apoferritin, in order to form single-layers, double-layers, as well as several types of 3D protein lattices. Our study demonstrates that internal voxel design and inter-voxel encoding can be effectively employed to create protein lattices with designed organization, as confirmed by in situ X-ray scattering and cryo-electron microscopy 3D imaging. The assembled protein arrays maintain structural stability and biological activity in environments relevant for protein functionality. The framework design of the arrays then allows small molecules to access the ferritins and their iron cores and convert them into apoferritin arrays through the release of iron ions. The presented study introduces a platform approach for creating bio-active protein-containing ordered nanomaterials with desired 2D and 3D organizations. Organising proteins in 2D and 3D is needed to develop complex bimolecular materials for a range of applications. Here, the authors report the encapsulation of ferritin and apoferritin in DNA-based voxels with programmed assembly to generate both 2D and 3D protein lattices and demonstrate the retention of protein function.

Automated summary

The study demonstrates the creation of bio-active protein-containing ordered nanomaterials with desired 2D and 3D organizations through the encapsulation of proteins in DNA-based voxels and programmable assembly. This platform approach allows for the retention of protein function in the assembled protein arrays.