Synthesis and patterning of tunable multiscale materials with engineered cells

Abstract

Many natural biological systems - such as biofilms, shells and skeletal tissues - are able to assemble multifunctional and environmentally responsive multiscale assemblies of living and non-living components. Here, by using inducible genetic circuits and cellular communication circuits to regulate Escherichia coli curli amyloid production, we show that E. coli cells can organize self-assembling amyloid fibrils across multiple length scales, producing amyloid-based materials that are either externally controllable or undergo autonomous patterning. We also interfaced curli fibrils with inorganic materials, such as gold nanoparticles (AuNPs) and quantum dots (QDs), and used these capabilities to create an environmentally responsive biofilm-based electrical switch, produce gold nanowires and nanorods, co-localize AuNPs with CdTe/CdS QDs to modulate QD fluorescence lifetimes, and nucleate the formation of fluorescent ZnS QDs. This work lays a foundation for synthesizing, patterning, and controlling functional composite materials with engineered cells.

Programmable biofilm-based materials from engineered curli nanofibres

“…Other work has paved the way for the patterning and control of curli composition 14 . By combining such biofilm control strategies with the ability to widely programme the functional properties of the ECM as we present here with BIND platform, we envision a merging of synthetic biology and materials science approaches.…”

“…Last, we demonstrate that the peptide domains maintain their function after secretion and assembly and confer artificial functions to the biofilm as a whole. Very recently, Chen et al 14 have demonstrated a parallel curli-based system similar to our BIND concept, and show controlled multiscale patterning of single amyloid fibres and the use of engineered curli for the organization of gold nanoparticles and quantum dots for nanoelectronics applications. Herein, we expand on the functions that can be engineered into curli nanofibres by demonstrating three broad functions that we artificially introduce into the E. coli biofilm ECM: inorganic nanoparticle templating, specific abiotic substrate adhesion and the site-specific covalent immobilization of an arbitrary functionalized recombinant protein.…”

Engineering control of bacterial cellulose production using a genetic toolkit and a new cellulose-producing strain

“…Although it is still unclear why Acetobacteraceae produce bacterial cellulose in nature (7), it has been shown to confer the host with a high resistance to UV light and a competitive advantage in colonization over other microorganisms (10). In materials science, genetic engineering has been used to create several novel biomaterials, such as strong underwater protein-based adhesives (11), self-assembling, functionalized amyloid-based biofilms (12), biodegradable bacterial cellulose-based tissue engineering scaffolds (13), and many others. Bacterial cellulose has long been a focus of research because, unlike plant-based cellulose, it is pure of other chemical species (lignin and pectin) and is synthesized as a continuous highly interconnected lattice (14).…”

Spatially orthogonal chemical functionalization of a hierarchical pore network for catalytic cascade reactions

“…2 two-photon excitation of hydrogels over planar substrates 11 , or through biogenic routes 12 . Such approaches respectively incorporate only a single chemically distinct function, require optically transparent and photoresponsive materials, or impart a poor degree of ordering and limited thermochemical stability.…”