Engineered mosaic protein polymers; a simple route to multifunctional biomaterials.

Area of Science:

• Biomaterials Science
• Synthetic Biology
• Protein Engineering

Background:

• Engineered living materials (ELMs) offer a new avenue for creating functional materials using living organisms.
• Protein-based ELMs, like Caf1, are advantageous due to their tunable properties via molecular biology.
• Caf1 is a bacterial protein exported as a robust, non-covalent polymer, suitable for biomaterial development.

Purpose of the Study:

• To engineer mosaic heteropolymers from engineered Caf1 subunits.
• To demonstrate the utility of these mosaic polymers in stimulating bone formation.
• To explore the complexity of Caf1 mosaic polymers through synthetic biology.

Main Methods:

• Utilizing gel electrophoresis and transmission electron microscopy to characterize mosaic heteropolymers.
• Co-expressing engineered Caf1 subunits in Escherichia coli.
• Employing a synthetic biology approach to create multi-component Caf1 mosaics.

Main Results:

• Bacterial cells successfully assembled engineered Caf1 subunits into true mosaic heteropolymers.
• Demonstrated the stimulation of early bone formation using a two-component mosaic polymer with primary human bone marrow stromal cells.
• Engineered a three-component Caf1 mosaic, indicating complexity is dependent on monomer variety.

Conclusions:

• Engineered Caf1 mosaic polymers provide a straightforward method for producing multifunctional biomaterials.
• These biomaterials hold potential for biomedical applications, including 3D tissue culture and wound healing.
• In situ production of Caf1 by engineered cells could lead to advanced bacterial communities for biotechnology.