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

Abstract

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.

Characterization of The Electrical and Optical Properties of Ultrabithorax Fusion Fibers for Biosensing

“…The fluorescence emission spectra of Ubx, EGFP‐Ubx, mCherry‐Ubx, and myoglobin‐Ubx solutions were measured using the 343 nm excitation wavelength ( Figure ). These measurements complement the measurements previously performed by the Bondos group [ 49 ] and provide a reference for subsequent measurements of the optical spectra of Ubx materials. All Ubx fusion solutions have an emission peak at 387 nm and the emission intensity decays with increasing wavelength.…”

Characterisation and Functionalisation of Ultrabithorax Materials for Biosensing

“…The fluorescence emission spectra of Ubx, EGFP-Ubx, mCherry-Ubx, and myoglobin-Ubx solutions were measured using 343 nm excitation wavelength, as shown in figure 3.3.1. These measurements complement the measurements previously per- formed by the Bondos group [26] and provide a baseline for the subsequent measurements of the optical spectra of Ubx materials. Ubx fusion solutions all displayed an emission peak at 387 nm with the emission intensity sharply decaying with the increase in wavelength.…”

Immobilization and enhancement of a heterodimeric fluorescence biosensor in fibrous protein biomaterials

“…EGFP is very stable and is known to retain activity in Ubx monomers and fibers (Z. Huang, Salim, et al, 2011;Nayak, et al, 2011). Additionally, the excitation and emission spectra of fibers composed of s8:LOO8-Ubx matched those of fibers composed of EGFP-Ubx (Figure 3, solid lines).…”