Engineering Bacillus subtilis for the formation of a durable living biocomposite material

• Published in: Nature communications Vol. 12; no. 1; p. 7133
• Main Authors: Kang, Sun-Young, Pokhrel, Anaya, Bratsch, Sara, Benson, Joey J., Seo, Seung-Oh, Quin, Maureen B., Aksan, Alptekin, Schmidt-Dannert, Claudia
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 08-12-2021; Nature Publishing Group; Nature Portfolio
• Subjects: 631/326/2522; 631/61/54/1754; 631/61/54/991; 82/80; Bacillus subtilis; Bacillus subtilis - genetics; Bacillus subtilis - metabolism; Bacteria; Biochemistry; Biocompatible Materials - chemistry; Biomedical materials; Biomineralization; Cell adhesion; Composite materials; Composite Resins; Crosslinking; Engineering; Engineers; Extracellular matrix; Fabrication; Flagella; Flagella - genetics; Genetic algorithms; Genetic Engineering - methods; Humanities and Social Sciences; Mechanical properties; Mineralization; multidisciplinary; Peptides; Polymerization; Polypeptides; Proteins; Regeneration; Scaffolds; Science; Science (multidisciplinary); Self-assembly; Silica; Silicon Dioxide; Spores; Spores, Bacterial - genetics; Synthetic biology
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-021-27467-2

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.
Despite the advances in engineered living materials (ELMs), the diversity of ELMs especially those that are capable of autonomous self-fabrication and regeneration, is low. Here, the authors engineer a resilient ELM biocomposite using
Bacillus subtilis
and secreted EutM proteins as selfassembling scaffold building blocks.