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Abstract Engineered living materials (ELMs) are a fast-growing area of research that combine approaches in synthetic biology and material science. Here, we engineer B. subtilis to become a living component of a silica material composed of self-assembling protein scaffolds for functionalization and cross-linking of cells. B. subtilis is engineered to display SpyTags on polar flagella for cell attachment to SpyCatcher modified secreted scaffolds. We engineer endospore limited B. subtilis cells to become a structural component of the material with spores for long-term storage of genetic programming. Silica biomineralization peptides are screened and scaffolds designed for silica polymerization to fabricate biocomposite materials with enhanced mechanical properties. We show that the resulting ELM can be regenerated from a piece of cell containing silica material and that new functions can be incorporated by co-cultivation of engineered B. subtilis strains. We believe that this work will serve as a framework for the future design of resilient ELMs.
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Robust Self‐Regeneratable Stiff Living Materials Fabricated from Microbial Cells
Living systems have not only the exemplary capability to fabricate materials (e.g., wood, bone) under ambient conditions but they also consist of living cells that imbue them with properties like growth and self-regeneration. Like a seed that can grow into a sturdy living wood, can living cells alone serve as the primary building block to fabricate stiff materials? Here is reported the fabrication of stiff living materials (SLMs) produced entirely from microbial cells, without the incorporation of any structural biopolymers (e.g., cellulose, chitin, collagen) or biominerals (e.g., hydroxyapatite, calcium carbonate) that are known to impart stiffness to biological materials. Remarkably, SLMs are also lightweight, strong, and resistant to organic solvents and can self- regenerate. This living materials technology can serve as a powerful biomanu- facturing platform to design and develop advanced structural and cellular materials in a sustainable manner.
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- Award ID(s):
- 2004875
- PAR ID:
- 10226118
- Date Published:
- Journal Name:
- Advanced Functional Materials
- ISSN:
- 1616-301X
- Page Range / eLocation ID:
- 2010784
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1002/adfm.202010784
