Polyhydroxyalkanoates (PHAs) are a diverse family of sustainable bioplastics synthesized by various bacteria, but their high production cost and unstable material properties make them challenging to ...use in commercial applications. Current industrial biotechnology (CIB) employs conventional microbial chassis, leading to high production costs. However, next-generation industrial biotechnology (NGIB) approaches, based on fast-growing and contamination-resistant extremophilic Halomonas spp., allow stable continuous processing and thus economical production of PHAs with stable properties. Halomonas spp. designed and constructed using synthetic biology not only produce low-cost intracellular PHAs but also secrete extracellular soluble products for improved process economics. Next-generation industrial biotechnology is expected to reduce the bioproduction cost and process complexity, leading to successful commercial production of PHAs.
The high production cost, poor thermal and mechanical properties, and unstable quality of polyhydroxyalkanoates (PHAs) are the grand challenges to be addressed before industrialization.Next-generation industrial biotechnology (NGIB) based on extremophiles is emerging to meet most of these challenges.Fast-growing and contamination-resistant Halomonas spp. allow open, unsterile, and continuous fermentations to produce PHAs with low-cost and stable properties.Halomonas spp. constructed by synthetic biology generate large sizes for PHA accumulation and gravity separation or coproduction of extracellular soluble products.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Abstract
Background
The duration of humoral and T and B cell response after the infection of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) remains unclear.
Methods
We performed a ...cross-sectional study to assess the virus-specific antibody and memory T and B cell responses in coronavirus disease 2019 (COVID-19) patients up to 343 days after infection. Neutralizing antibodies and antibodies against the receptor-binding domain, spike, and nucleoprotein of SARS-CoV-2 were measured. Virus-specific memory T and B cell responses were analyzed.
Results
We enrolled 59 patients with COVID-19, including 38 moderate, 16 mild, and 5 asymptomatic patients; 31 (52.5%) were men and 28 (47.5%) were women. The median age was 41 years (interquartile range, 30–55). The median day from symptom onset to enrollment was 317 days (range 257 to 343 days). We found that approximately 90% of patients still have detectable immunoglobulin (Ig)G antibodies against spike and nucleocapsid proteins and neutralizing antibodies against pseudovirus, whereas ~60% of patients had detectable IgG antibodies against receptor-binding domain and surrogate virus-neutralizing antibodies. The SARS-CoV-2-specific IgG+ memory B cell and interferon-γ-secreting T cell responses were detectable in more than 70% of patients.
Conclusions
Severe acute respiratory syndrome coronavirus 2-specific immune memory response persists in most patients approximately 1 year after infection, which provides a promising sign for prevention from reinfection and vaccination strategy.
SARS-CoV-2-specific antibody and memory T and B cell responses were detectable in most patients approximately 1 year after infection, indicating that durable immunity against secondary COVID-19 disease is possible in most individuals.
Polyhydroxyalkanoates (PHAs) are a diverse family of biopolyesters synthesized by many natural or engineered bacteria. Synthetic biology and DNA-editing approaches have been adopted to engineer cells ...for more efficient PHA production. Recent advances in synthetic biology applied to improve PHA biosynthesis include ribosome-binding site (RBS) optimization, promoter engineering, chromosomal integration, cell morphology engineering, cell growth behavior reprograming, and downstream processing. More importantly, the genome-editing tool clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein 9 (Cas9) has been applied to optimize the PHA synthetic pathway, regulate PHA synthesis-related metabolic flux, and control cell shapes in model organisms, such as Escherichia coli, and non-model organisms, such as Halomonas. These synthetic biology methods and genome-editing tools contribute to controllable PHA molecular weights and compositions, enhanced PHA accumulation, and easy downstream processing.
The bioplastic PHA, which features biodegradability, biocompatibility, and thermoprocessibility, is moving toward low-cost microbial production to replace nondegradable petrochemical plastics.Wild-type or weakly engineered bacteria are insufficient to meet demands for improved PHA structures and low production cost.Synthetic biology and genome-editing approaches can promote PHA synthesis, enlarge cells for more PHA storage, control shape changes, accelerate growth, aid the co-production of multiple products, direct flux toward final products, and make product recovery more convenient.Optimized promoters and RBSs increase the expression of PHA synthesis genes.CRISPR interference and CRISPR/Cas9 are useful for downregulating the expression of multiple genes simultaneously, allowing more flux to be directed to PHA synthesis in an optimized strain.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The outstanding efficiency of Fe‐based metallic glass powders in degrading organic water contaminants is reported. While the glassy alloy contains 24% chemically inactive metalloid elements, the ...powders are capable to completely decompose the C32H20N6Na4O14S4 azo dye in aqueous solution in short time, about 200 times faster than the conventional Fe powders. The metastable thermodynamic nature and the particle surface topography are the major factors controlling the chemical performance of the metallic glass. Our findings may open a new opportunity for functional applications of metallic glasses.
Fe‐based metallic glass powders show outstanding efficiency in degrading organic contaminants due to their far‐from‐equilibrium thermodynamic nature. The –N=N– bond of the dye can be completely decomposed in a short time. Higher degradation efficiency can be achieved by tailoring the particle morphology. The findings are expected to open new areas for the applications of metallic glasses.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Adipocyte differentiation of bone marrow mesenchymal stem/stromal cells (BMSCs) instead of osteoblast formation contributes to age- and menopause-related marrow adiposity and osteoporosis. Vascular ...calcification often occurs with osteoporosis, a contradictory association called "calcification paradox". Here we show that extracellular vesicles derived from aged bone matrix (AB-EVs) during bone resorption favor BMSC adipogenesis rather than osteogenesis and augment calcification of vascular smooth muscle cells. Intravenous or intramedullary injection of AB-EVs promotes bone-fat imbalance and exacerbates Vitamin D3 (VD3)-induced vascular calcification in young or old mice. Alendronate (ALE), a bone resorption inhibitor, down-regulates AB-EVs release and attenuates aging- and ovariectomy-induced bone-fat imbalance. In the VD3-treated aged mice, ALE suppresses the ovariectomy-induced aggravation of vascular calcification. MiR-483-5p and miR-2861 are enriched in AB-EVs and essential for the AB-EVs-induced bone-fat imbalance and exacerbation of vascular calcification. Our study uncovers the role of AB-EVs as a messenger for calcification paradox by transferring miR-483-5p and miR-2861.
The oxygen reduction reaction (ORR) is one of the most important reactions in life processes and energy conversion systems. To alleviate global warming and the energy crisis, the development of ...high‐performance electrocatalysts for the ORR for application in energy conversion and storage devices such as metal–air batteries and fuel cells is highly desirable. Inspired by the biological oxygen activation/reduction process associated with heme‐ and multicopper‐containing metalloenzymes, iron and copper‐based transition‐metal complexes have been extensively explored as ORR electrocatalysts. Herein, an outline into recent progress on non‐precious‐metal electrocatalysts for the ORR is provided; these electrocatalysts do not require pyrolysis treatment, which is regarded as desirable from the viewpoint of bioinspired molecular catalyst design, focusing on iron/cobalt macrocycles (porphyrins, phthalocyanines, and corroles) and copper complexes in which the ORR activity is tuned by ligand variation/substitution, the method of catalyst immobilization, and the underlying supporting materials. Current challenges and exciting imminent developments in bioinspired ORR electrocatalysts are summarized and proposed.
An outline of recent progress on non‐precious‐metal electrocatalysts for the oxygen reduction reaction (ORR) is presented from the viewpoint of bioinspired molecular catalyst design, with a focus on iron/cobalt macrocycles and copper complexes in which the ORR activity is tuned by ligand modification, the method of catalyst immobilization, and the underlying supporting materials (see scheme).
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
ABSTRACT
The cosmological-constant (Λ) cold dark matter (CDM) model is challenged by the Hubble tension, a remarkable difference of Hubble constant H0 between measurements from local probes and the ...prediction from Planck cosmic microwave background observations under ΛCDM model. So one urgently needs new distance indicators to test the Hubble tension. Fast radio bursts (FRBs) are millisecond-duration pulses occurring at cosmological distances, which are attractive cosmological probes. Here, we report a measurement of ${H_0} = 68.81^{+4.99}_{-4.33} {\rm \ km \ s^{-1} \ Mpc^{-1}}$ using eighteen localized FRBs, with an uncertainty of 8 per cent at 68.3 per cent confidence. Using a simulation of 100 localized FRBs, we find that error of H0 can be reduced to 2.6 per cent at 1σ uncertainty. Thanks to the high event rate of FRBs and localization capability of radio telescopes (i.e. Australian Square Kilometre Array Pathfinder and Very Large Array), future observations of a reasonably sized sample will provide a new way of measuring H0 with a high precision to test the Hubble tension.
The good co‐existence of midgap state and valence band degeneracy is realized in Bi‐alloyed GeTe through the In‐Cd codoping to play different but complementary roles in the valence band structure ...modification. In doping induces midgap state and results in a considerably improved Seebeck coefficient near room temperature, while Cd doping significantly increases the Seebeck coefficient in the mid‐high temperature region by promoting the valence band convergence. The synergistic effects obviously increase the density of state effective mass from 1.39 to 2.65 m0, and the corresponding carrier mobility still reaches 34.3 cm2 V−1 s−1 at room temperature. Moreover, the Bi‐In‐Cd co‐alloying introduces various phonon scattering centers including nanoprecipitates and strain field fluctuations and suppresses the lattice thermal conductivity to a rather low value of 0.56 W m−1 K−1 at 600 K. As a result, the Ge0.89Bi0.06In0.01Cd0.04Te sample obtains excellent thermoelectric properties of zTmax ≈2.12 at 650 K and zTavg ≈1.43 between 300 and 773 K. This study illustrates that the thermoelectric performance of GeTe can be optimized in a wide temperature range through the synergy of midgap state and valence band convergence.
It is revealed that the good coexistence of midgap state and band convergence in GeTe improves the thermoelectric performance over a very broad temperature range. Since the high md∗$m_d^ * $ is obtained and the κl is reduced, the thermoelectric performance of GeTe is significantly improved, leading to a high zTmax of 2.12 at 650 K and a greatly improved zTavg of 1.43 between 300 and 773 K.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Fine particulate matter (PM2.5) is the primary air pollutant that is able to induce airway injury. Compelling evidence has shown the involvement of IL‐17A in lung injury, while its contribution to ...PM2.5‐induced lung injury remains largely unknown. Here, we probed into the possible role of IL‐17A in mouse models of PM2.5‐induced lung injury. Mice were instilled with PM2.5 to construct a lung injury model. Flow cytometry was carried out to isolate γδT and Th17 cells. ELISA was adopted to detect the expression of inflammatory factors in the supernatant of lavage fluid. Primary bronchial epithelial cells (mBECs) were extracted, and the expression of TGF signalling pathway‐, autophagy‐ and PI3K/Akt/mTOR signalling pathway‐related proteins in mBECs was detected by immunofluorescence assay and Western blot analysis. The mitochondrial function was also evaluated. PM2.5 aggravated the inflammatory response through enhancing the secretion of IL‐17A by γδT/Th17 cells. Meanwhile, PM2.5 activated the TGF signalling pathway and induced EMT progression in bronchial epithelial cells, thereby contributing to pulmonary fibrosis. Besides, PM2.5 suppressed autophagy of bronchial epithelial cells by up‐regulating IL‐17A, which in turn activated the PI3K/Akt/mTOR signalling pathway. Furthermore, IL‐17A impaired the energy metabolism of airway epithelial cells in the PM2.5‐induced models. This study suggested that PM2.5 could inhibit autophagy of bronchial epithelial cells and promote pulmonary inflammation and fibrosis by inducing the secretion of IL‐17A in γδT and Th17 cells and regulating the PI3K/Akt/mTOR signalling pathway.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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