In contrast to the current paradigm of using microbial mono‐cultures in most biotechnological applications, increasing efforts are being directed towards engineering mixed‐species consortia to perform functions that are difficult to programme into individual strains. In this work, we developed a synthetic microbial consortium composed of two genetically engineered microbes, a cyanobacterium (
The field of engineered living materials lies at the intersection of materials science and synthetic biology with the aim of developing materials that can sense and respond to the environment. In this study, we use 3D printing to fabricate a cyanobacterial biocomposite material capable of producing multiple functional outputs in response to an external chemical stimulus and demonstrate the advantages of utilizing additive manufacturing techniques in controlling the shape of the fabricated photosynthetic material. As an initial proof-of-concept, a synthetic riboswitch is used to regulate the expression of a yellow fluorescent protein reporter in
- NSF-PAR ID:
- 10439349
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 14
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Summary Synechococcus elongatus PCC 7942) and a heterotrophic bacterium (Pseudomonas putida EM173). These microbial species specialize in the co‐culture: cyanobacteria fix CO2through photosynthetic metabolism and secrete sufficient carbohydrates to support the growth and active metabolism ofP. putida , which has been engineered to consume sucrose and to degrade the environmental pollutant 2,4‐dinitrotoluene (2,4‐DNT). By encapsulatingS. elongatus within a barium–alginate hydrogel, cyanobacterial cells were protected from the toxic effects of 2,4‐DNT, enhancing the performance of the co‐culture. The synthetic consortium was able to convert 2,4‐DNT with light and CO2as key inputs, and its catalytic performance was stable over time. Furthermore, cycling this synthetic consortium through low nitrogen medium promoted the sucrose‐dependent accumulation of polyhydroxyalkanoate, an added‐value biopolymer, in the engineeredP. putida strain. Altogether, the synthetic consortium displayed the capacity to remediate the industrial pollutant 2,4‐DNT while simultaneously synthesizing biopolymers using light and CO2as the primary inputs. -
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