Virus-Based Biomimetic Collagen Supramolecular Structure and Function

Collagen is a major component of the extracellular matrix and serves as a scaffold for the growth of minerals and cells in our body. As secreted from osteoblast cells, collagen triple helices spontaneously form a supramolecular structure, mostly fibrils and interact with other constituents in connective tissues from nano- to macroscopic length scales. Various materials were reported to mimic the hierarchical structure and function of collagen; however, creating a higher-order supramolecular collagen-like structure is still challenging. Here we develop a bio-mimetic approach to create the hierarchical collagen-like structure and biological function using M13 bacteriophage (phage). Through phage display – a high-throughput screening process, we identified a new phage engineered with a collagen-like peptide that can strongly bind to bone hydroxyapatite crystals, termed as a collagen-like phage. We then exploit the collagen-like phage to develop bone-tissue like hierarchical structures and tissue functions. Using a self-templating assembly process, we show the collagen-like phage can self-assemble supramolecular structures with a smectic periodic band and quasi-hexagonal packed crystalline ordered structure. The resulting self-assembled structures can direct biomineralization and guide directional growth of cells. Our new approach to develop biomimetic materials will be broadly used for other materials to create a hierarchically organized structure and desired function.