Programmable assembly of pressure sensors using pattern-forming bacteria

Abstract

Biological systems can generate microstructured materials that combine organic and inorganic components and possess diverse physical and chemical properties. However, these natural processes in materials fabrication are not readily programmable. Here, we use a synthetic-biology approach to mimic such natural processes to assemble patterned materials.. We demonstrate programmable fabrication of three-dimensional (3D) materials by printing engineered self-patterning bacteria on permeable membranes that serve as a structural scaffold. Application of gold nanoparticles to the colonies creates hybrid organic-inorganic dome structures. The dynamics of the dome structures' response to pressure is determined by their geometry (colony size, dome height and pattern), which is easily modified by varying the properties of the membrane (e.g., pore size and hydrophobicity). We generate resettable pressure sensors that process signals in response to varying pressure intensity and duration.

Controlling spatiotemporal pattern formation in a concentration gradient with a synthetic toggle switch

“…Future work will reveal if the TS properties are conserved when incorporated in more complex (synthetic) gene regulatory networks, for example when combined with the repressilator (Elowitz and Leibler, 2000, Potvin-Trottier et al, 2016, Santos-Moreno and Schaerli, 2019a to yield the AC-DC network (Perez-Carrasco et al, 2018, Verd et al, 2019, Balaskas et al, 2012, Panovska-Griffiths et al, 2013. Moreover, the here established engineering guidelines on how to control patterning with a synthetic TS will be valuable for future synthetic pattern formation, for example in the context of engineered living materials based on bacterial biofilms (Gilbert and Ellis, 2018, Nguyen et al, 2018, Moser et al, 2019, Cao et al, 2017.…”

“…The rise of synthetic biology has successfully allowed to build synthetic systems able to explore core patterning principles (reviewed in (Santos-Moreno and Schaerli, 2019b, Luo et al, 2019, Davies, 2017, Ebrahimkhani and Ebisuya, 2019). In addition, synthetic pattern formation is also an attractive technology for the engineering of living materials (Gilbert and Ellis, 2018, Nguyen et al, 2018, Moser et al, 2019, Cao et al, 2017 and tissues (Davies and Cachat, 2016, Healy and Deans, 2019, Webster et al, 2016.…”

Light‐Controlled, High‐Resolution Patterning of Living Engineered Bacteria Onto Textiles, Ceramics, and Plastic

“…Curli fiber synthesis has been previously placed under the control of genetic sensors and circuits. The control of CsgA by chemical inducers and cell–cell communication signals has been used to change the content of alternative subunits within curli fibers and to promote the self‐assembly of conductive fibers to form a pressure sensing device . Various optogenetic tools have also been used to toggle cell adhesion, disrupt biofilms of medical interest, and to pattern biofilms at high resolution on a 2D surface …”

Synthetic biology—Engineering nature to make materials

“…Lingchong You and his co-workers at Duke University have used it to assemble pressure sensors. 21 They programmed their curli-making bacteria by engineering a gene circuit to self-assemble into a three-dimensional shape on a porous membrane that dictated the structure of the curli biofilm and the inorganic components it templated. They used inkjet printing to create an array of bacterial colonies on the membrane, each of which grew into a hemispherical shape covered by a dome of curli fibrils to which gold nanoparticles could be attached.…”