Spectroscopy and Analytical Techniques

Ultrabithorax (Ubx) is a Drosophila melanogaster transcription factor protein the Bondos group discovered has the ability to form ordered materials in vitro. Ubx monomers are produced in E.coli and, following purification, are suspended in a buffer solution and where they do not aggregate in the volume of the solution when refrigerated. When allowed to rest at room temperature, the monomer self assembles at the air/water interface through nucleation, fibril formation and, eventually, film integration. The the self assembled film can then be pulled into a fibre with diameters in the range of 2–50 μm or lifted off as a film with microscale thickness. These materials are highly elastic and maintain physical properties through cycles of drying and re-hydrating. Novel functions can be directly incorporated into Ubx-based materials via gene fusion to produce chimeric polypeptides capable of both self-assembly and the desired chemical reactivity. Unlike most protein-based materials, the gentle conditions under which Ubx self-assembles enable incorporation of active heterologous proteins. This talk will review recent work on the continued development of this unique materials system including mechanical properties enabled by dityrosine bonding between monomers, dynamics of surface film assembly, and advances in Ubxbased

materials production.