Most mono- and co-culture bioprocess applications rely on large-scale suspension fermentation technologies that are not easily portable, reusable, or suitable for on-demand production. Here, we ...describe a hydrogel system for harnessing the bioactivity of embedded microbes for on-demand small molecule and peptide production in microbial mono-culture and consortia. This platform bypasses the challenges of engineering a multi-organism consortia by utilizing a temperature-responsive, shear-thinning hydrogel to compartmentalize organisms into polymeric hydrogels that control the final consortium composition and dynamics without the need for synthetic control of mutualism. We demonstrate that these hydrogels provide protection from preservation techniques (including lyophilization) and can sustain metabolic function for over 1 year of repeated use. This approach was utilized for the production of four chemical compounds, a peptide antibiotic, and carbohydrate catabolism by using either mono-cultures or co-cultures. The printed microbe-laden hydrogel constructs' efficiency in repeated production phases, both pre- and post-preservation, outperforms liquid culture.
Metabolic engineering allows for the rewiring of basic metabolism to overproduce both native and non-native metabolites. Among these biomolecules, nutraceuticals have received considerable interest ...due to their health-promoting or disease-preventing properties. Likewise, microbial engineering efforts to produce these value-added nutraceuticals overcome traditional limitations of low yield from extractions and complex chemical syntheses. This review covers current strategies of metabolic engineering employed for the production of a few key nutraceuticals with selecting polyunsaturated fatty acids, polyphenolic compounds, carotenoids and non-proteinogenic amino acids as exemplary molecules. We focus on the use of both mono-culture and co-culture strategies to produce these molecules of interest. In each of these cases, metabolic engineering efforts are enabling rapid production of these molecules.
Engineered living materials (ELMs) combine living cells with polymeric matrices to yield unique materials with programmable functions. While the cellular platform and the polymer network determine ...the material properties and applications, there are still gaps in the ability to seamlessly integrate the biotic (cellular) and abiotic (polymer) components into singular materials, then assemble them into devices and machines. Herein, the additive‐manufacturing of ELMs wherein bioproduction of metabolites from the encapsulated cells enhanced the properties of the surrounding matrix is demonstrated. First, aqueous resins are developed comprising bovine serum albumin (BSA) and poly(ethylene glycol diacrylate) (PEGDA) with engineered microbes for vat photopolymerization to create objects with a wide array of 3D form factors. The BSA‐PEGDA matrix afforded hydrogels that are mechanically stiff and tough for use in load‐bearing applications. Second, the continuous in situ production of l‐DOPA, naringenin, and betaxanthins from the engineered cells encapsulated within the BSA‐PEGDA matrix is demonstrated. These microbial metabolites bioaugmented the properties of the BSA‐PEGDA matrix by enhancing the stiffness (l‐DOPA) or resistance to enzymatic degradation (betaxanthin). Finally, the assembly of the 3D printed ELM components into mechanically functional bolts and gears to showcase the potential to create functional ELMs for synthetic living machines is demonstrated.
The additive manufacturing of sustainable engineered living materials (ELM) with arbitrary 3D form factors is further enhanced via bioaugmentation and affords operational machines: engineered cells produce chemical agents in situ to introduce a new function or capability to the material, and also contribute to material properties in manner that is complementary to the existing polymer matrix.
The quality and quantity of mulberry leaves are often affected by various environmental factors. The plant NPR1 and its homologous genes are important for plant systemic acquired resistance. Here, ...the full‐length cDNAs encoding the NPR1 and NPR4 genes (designated MuNPR1 and MuNPR4, respectively) were isolated from Morus multicaulis. Sequence analysis of the amino acids and protein modeling of the MuNPR1 and MuNPR4 proteins showed that MuNPR1 shares some conserved characteristics with its homolog MuNPR4. MuNPR1 was shown to have different expression patterns than MuNPR4 in mulberry plants. Interestingly, MuNPR1 or MuNPR4 transgenic Arabidopsis produced an early flowering phenotype, and the expression of the pathogenesis‐related 1a gene was promoted in MuNPR1 transgenic Arabidopsis. The MuNPR1 transgenic plants showed more resistance to Pseudomonas syringae pv. tomato DC3000 (Pst. DC3000) than did the wild‐type Arabidopsis. Moreover, the ectopic expression of MuNPR1 might lead to enhanced scavenging ability and suppress collase accumulation. In contrast, the MuNPR4 transgenic Arabidopsis were hypersensitive to Pst. DC3000 infection. In addition, transgenic Arabidopsis with the ectopic expression of either MuNPR1 or MuNPR4 showed sensitivity to salt and drought stresses. Our data suggest that both the MuNPR1 and MuNPR4 genes play a role in the coordination between signaling pathways, and the information provided here enables the in‐depth functional analysis of the MuNPR1 and MuNPR4 genes and may promote mulberry resistance breeding in the future.
Currently, all inorganic perovskite quantum dots (QDs) of cesium lead halides (CsPbX
3
, X = Cl, Br, and I) have been mainly fabricated using wet chemical methods. Unfortunately, applications of ...perovskite QDs have been limited due to their poor stability. In the present work, the
in situ
growth of whole-family CsPbX
3
(X = Cl, Br, and I) perovskite QDs in Zn-P-B-Sb based oxide glass
via
a glass crystallization strategy is reported. The as-prepared CsPbX
3
QDs@glass nanocomposites exhibit typical excitonic recombination emissions and superior chemical stability benefited from the protection of the robust inorganic glass matrix. Through modifying the molar ratio of halide sources in glass, multi-color tunable emissions in the entire visible spectral range of 400-750 nm are achieved. As a result, light-emitting diode devices can be constructed by coupling blue-emissive CsPbBrCl
2
, green-emissive CsPbBr
3
and red-emissive CsPbBr
0.5
I
2.5
QDs@glass powders with a commercial ultraviolet chip, yielding bright white light luminescence with excellent optoelectronic performance.
CsPbX
3
(X = Cl, Br, I and their mixture) QDs@glass nanocomposites are fabricated
via
a facile
in situ
glass crystallization strategy, exhibiting full-spectral visible emissions, superior thermal stability and water resistance.
A solar-blind photodetector (PD) based on the cosputtered aluminum-gallium oxide (AGO) material after thermal annealing at 900 °C has been demonstrated using a metal-semiconductor-metal structure. By ...incorporating optimum trace aluminum (Al), the AGO PD shows the peak responsivity (at 230 nm) of 1.38 A/W under a bias voltage of 5 V, which is 53.61 times greater than that of the PD from the gallium oxide (GO) film without incorporating any Al content. The photocurrent, dark current, and detectivity (at 5 V and 230 nm) of AGO PD are also improved to be 46.4, 0.83, and 96.5 times, respectively, greater than those of GO one. Unlike conventional GO samples revealing obvious drop in spectral response from 250 to 200 nm, the AGO PD with an Al/(Al + Ga) ratio of 1.8% exhibits a nearly flat responsivity curve in the deep ultraviolet region. This improvement is significant compared with previous reports for the GO and AGO PDs by other growth methods.
In this study, artificial intelligence and image recognition technologies are combined with environmental sensors and the Internet of Things (IoT) for pest identification. Real-time agricultural ...meteorology and pest identification systems on mobile applications are evaluated based on intelligent pest identification and environmental IoT data. We combined the current mature AIoT technology and deep learning and applied it to smart agriculture. We used deep learning YOLOv3 for image recognition to obtain the location of Tessaratoma papillosa and analyze the environmental information from weather stations through Long Short-Term Memory (LSTM) to predict the occurrence of pests. The experimental results showed that the pest identification accuracy reached 90%. Precise positioning can effectively reduce the amount of pesticides used and reduce pesticide damage to the soil. The current research provides the location of the pest and the extent of the pests to farmers can accurately use pesticide application at a precise time and place and thus reduce the agricultural workforce required for timely pest control, thus achieving the goal of smart agriculture. The proposed system notifies farmers of the presence of different pests before they start multiplying in large numbers. It improves overall agricultural economic value by providing appropriate pest control methods that decrease crop losses and reduce the environmental damage caused by the excessive usage of pesticides.
Resveratrol is a plant secondary metabolite with diverse, potential health-promoting benefits. Due to its nutraceutical merit, bioproduction of resveratrol via microbial engineering has gained ...increasing attention and provides an alternative to unsustainable chemical synthesis and straight extraction from plants. However, many studies on microbial resveratrol production were implemented with the addition of water-insoluble phenylalanine or tyrosine-based precursors to the medium, limiting in the sustainable development of bioproduction.
Here we present a novel coculture platform where two distinct metabolic background species were modularly engineered for the combined total and de novo biosynthesis of resveratrol. In this scenario, the upstream Escherichia coli module is capable of excreting p-coumaric acid into the surrounding culture media through constitutive overexpression of codon-optimized tyrosine ammonia lyase from Trichosporon cutaneum (TAL), feedback-inhibition-resistant 3-deoxy-d-arabinoheptulosonate-7-phosphate synthase (aroG
) and chorismate mutase/prephenate dehydrogenase (tyrA
) in a transcriptional regulator tyrR knockout strain. Next, to enhance the precursor malonyl-CoA supply, an inactivation-resistant version of acetyl-CoA carboxylase (ACC1
) was introduced into the downstream Saccharomyces cerevisiae module constitutively expressing codon-optimized 4-coumarate-CoA ligase from Arabidopsis thaliana (4CL) and resveratrol synthase from Vitis vinifera (STS), and thus further improve the conversion of p-coumaric acid-to-resveratrol. Upon optimization of the initial inoculation ratio of two populations, fermentation temperature, and culture time, this co-culture system yielded 28.5 mg/L resveratrol from glucose in flasks. In further optimization by increasing initial net cells density at a test tube scale, a final resveratrol titer of 36 mg/L was achieved.
This is first study that demonstrates the use of a synthetic E. coli-S. cerevisiae consortium for de novo resveratrol biosynthesis, which highlights its potential for production of other p-coumaric-acid or resveratrol derived biochemicals.
This paper is concerned with the problem of adaptive event-triggered control for networked switched T-S fuzzy systems under false data injection attacks. In order to reduce unnecessary data ...transmission, an adaptive event-triggering mechanism is proposed, which can dynamically change triggering conditions based on system performance needs. In particular, due to the consideration of network safety, the system will be subjected to the impacts from both attack delays and network transmission delays. Then, by a delay system transformation approach, a time-delay closed-loop switched T-S fuzzy system is obtained. Moreover, by utilizing average dwell time technique, stability conditions are developed for the closed-loop system with the adaptive event-triggering mechanism and false data injection attacks. In addition, a co-design of adaptive event-triggering parameters and controller gains is given. Finally, simulation results are provided to verify the effectiveness of the designed method.
Synthetic biology and metabolic engineering seek to re-engineer microbes into "living foundries" for the production of high value chemicals. Through a "design-build-test" cycle paradigm, massive ...libraries of genetically engineered microbes can be constructed and tested for metabolite overproduction and secretion. However, library generation capacity outpaces the rate of high-throughput testing and screening. Well plate assays are flexible but with limited throughput, whereas droplet microfluidic techniques are ultrahigh-throughput but require a custom assay for each target. Here we present RNA-aptamers-in-droplets (RAPID), a method that greatly expands the generality of ultrahigh-throughput microfluidic screening. Using aptamers, we transduce extracellular product titer into fluorescence, allowing ultrahigh-throughput screening of millions of variants. We demonstrate the RAPID approach by enhancing production of tyrosine and secretion of a recombinant protein in Saccharomyces cerevisiae by up to 28- and 3-fold, respectively. Aptamers-in-droplets affords a general approach for evolving microbes to synthesize and secrete value-added chemicals.Screening libraries of genetically engineered microbes for secreted products is limited by the available assay throughput. Here the authors combine aptamer-based fluorescent detection with droplet microfluidics to achieve high throughput screening of yeast strains engineered for enhanced tyrosine or streptavidin production.
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