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Abstract The field of hybrid engineered living materials seeks to pair living organisms with synthetic materials to generate biocomposite materials with augmented function since living systems can provide highly-programmable and complex behavior. Engineered living materials have typically been fabricated using techniques in benign aqueous environments, limiting their application. In this work, biocomposite fabrication is demonstrated in which spores from polymer-degrading bacteria are incorporated into a thermoplastic polyurethane using high-temperature melt extrusion. Bacteria are engineered using adaptive laboratory evolution to improve their heat tolerance to ensure nearly complete cell survivability during manufacturing at 135 °C. Furthermore, the overall tensile properties of spore-filled thermoplastic polyurethanes are substantially improved, resulting in a significant improvement in toughness. The biocomposites facilitate disintegration in compost in the absence of a microbe-rich environment. Finally, embedded spores demonstrate a rationally programmed function, expressing green fluorescent protein. This research provides a scalable method to fabricate advanced biocomposite materials in industrially-compatible processes.
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Data from: Catalytic materials enabled by a programmable assembly of synthetic polymers and bacterial spores
{"Abstract":["Natural biological materials are formed by self-assembly processes and\n catalyze a myriad of reactions. Here, we report a programmable molecular\n assembly of designed synthetic polymers with engineered Bacillus subtilis\n spores. The bacterial spore-based materials possess modular mechanical and\n functional properties derived from the independent design and assembly of\n synthetic polymers and engineered spores . We discovered that\n phenylboronic acid (PBA) derivatives form tunable and reversible dynamic\n covalent bonds with the spore surface glycan. Spore labeling was performed\n using fluorescent PBA probes and monitored by fluorescence microscopy and\n spectroscopy. Binding affinities of PBA derivatives to spore surface\n glycan was controlled by aryl substituent effects. On the basis of this\n finding, PBA-functionalized statistical copolymers were synthesized and\n assembled with B. subtilis spores to afford macroscopic materials that\n exhibited programmable stiffness, self-healing, prolonged dry storage, and\n recyclability. These material properties could be examined using shear\n rheology, tensile testing, and NMR experiments. Integration of engineered\n spores with surface enzymes yielded reusable biocatalytic materials with\n exceptional operational simplicity and high benchtop stability. The\n reaction progress of the biocatalyses could be monitored with fluorescence\n specroscopy and absorption measurements, while spore leakage could be\n monitored by changes in solution turbidity (OD600). The use of bacterial\n spores as an active partner in dynamic covalent crosslinking sets our\n material apart from previous examples and grants control over\n biocontainment as well as the subsequent fate of the spores through\n stimuli-responsive reversal of the crosslink."],"Methods":["All experimental methods are briefly described in the README.md file, and\n fully detailed in the Supporting Information file for the paper article\n "Catalytic materials enabled by a programmable assembly of synthetic\n polymers and engineered bacterial spores"."]}
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- Award ID(s):
- 2237344
- PAR ID:
- 10463472
- Publisher / Repository:
- Dryad
- Date Published:
- Edition / Version:
- 3
- Subject(s) / Keyword(s):
- FOS: Chemical sciences catalytic materials Organic synthesis polymer sythesis polymer materials Biocatalysis Bacterial spores boronic acid RAFT polymerization
- Format(s):
- Medium: X Size: 341614535 bytes
- Size(s):
- 341614535 bytes
- Sponsoring Org:
- National Science Foundation
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