Functionalization and Patterning of Protein‐Based Materials Using Active Ultrabithorax Chimeras

A key advantage of protein‐based materials is the potential to directly incorporate novel functions via gene fusion to produce a single chimeric polypeptide capable of both self‐assembly and the desired activity. However, facile production of functionalized protein materials is frequently hampered by the need to trigger materials assembly using conditions that will not irreversibly damage the functional protein. In contrast, the recombinant Drosophila melanogaster transcription factor Ultrabithorax (Ubx) rapidly self‐assembles under mild, aqueous conditions to form highly extensible materials with a variety of morphologies. Here, it is demonstrated that materials composed of Ubx chimeras with Enhanced Green Fluorescent Protein (EGFP), mCherry, luciferase, or myoglobin display the functions of the appended proteins, indicating that these activities are neither impaired by the assembly process nor by confinement within the materials. Finally, methods are established that combine EGFP‐Ubx and mCherry‐Ubx monomers to self‐assemble materials patterned on the microscale to macroscale. The self‐adhesive properties of Ubx materials also permit manual construction and patterning of more complex forms. The ability to easily functionalize and pattern protein‐based materials greatly expands their potential utility in a wide variety of applications.