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The continuous advancements in studying two-dimensional (2D) materials pave the way for groundbreaking innovations across various industries. In this study, by employing density functional theory calculations, we comprehensively elucidate the electronic structures of MZX (M = Ga and In; Z = Si, Ge, and Sn; X = S, Se, and Te) monolayers for their applications in photocatalytic, thermoelectric, and spintronic fields. Interestingly, GaSiS, GaSiSe, InSiS, and InSiSe monolayers are identified to be efficient photocatalysts for overall water splitting with band gaps close to 2.0 eV, suitable band edge positions, and excellent optical harvest ability. In addition, the InSiTe monolayer exhibits a ZT value of 1.87 at 700 K, making it highly appealing for applications in thermoelectric devices. It is further highlighted that GaSnTe, InSnS, and InSnSe monolayers are predicted to be 2D topological insulators (TIs) with bulk band gaps of 115, 54, and 152 meV, respectively. Current research expands the family of 2D GaGeTe materials and establishes a path toward the practical utilization of MZX monolayers in energy conversion and spintronic devices.
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The above article, published online on 5 December 2022, on Wiley Online Library (https://onlinelibrary.wiley.com/doi/abs/10.1002/htj.22448), has been withdrawn by agreement between the journal Editor in Chief, Hari Bhat, and Wiley Periodicals, LLC. The withdrawal has been agreed due to a technical error at the publisher that caused the article to be mistakenly published online although publication had been canceled because the authors did not approve their proof.
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Polyhydroxyalkanoates (PHA) have found widespread medical applications due to their biocompatibility and biodegradability, while further chemical modification requires functional groups on PHA. Halomonas bluephagenesis, a non-model halophilic bacterium serving as a chassis for the Next Generation Industrial Biotechnology (NGIB), was successfully engineered to express heterologous PHA synthase (PhaC) and enoyl coenzyme-A hydratase (PhaJ) from Aeromonas hydrophila 4AK4, along with a deletion of its native phaC gene to synthesize the short chain-co-medium chain-length PHA copolymers, namely poly(3-hydroxybutyrate-co-3-hydroxyhexanoate), poly(3-hydroxybutyrate-co-3-hydroxyhex-5-enoate) and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate-co-3-hydroxyhex-5-enoate). After optimizations of the expression cassette and ribosomal binding site combined with introduction of endogenous acyl-CoA synthetase (fadD), the resulting recombinant strain H. bluephagenesis TDR4 achieved a remarkably high 3-hydroxyhexenoate (3HHxE) molar ratio of 35% when grown on glucose and 5-hexenoic acid as co-substrates. The total ratio of side chain consisting of 3HHx and 3HHxE monomers in the terpolymer can approach 44 mol%. H. bluephagenesis TDR4 was grown to a cell dry mass (CDM) of 30 g/L containing approximately 20% poly(3-hydroxybutyrate-co-22.75 mol% 3-hydroxy-5-hexenoate) in a 48-h of open and unsterile fermentation with a 5-hexenoic acid conversion efficiency of 91%. The resulted functional PHA containing 12.5 mol% 3-hydroxy-5-hexenoate exhibits more than 1000% elongation at break. The engineered H. bluephagenesis TDR4 can be used as an experimental platform to produce functional PHA.
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Proteínas Bacterianas , Halomonas , Ingeniería Metabólica , Polihidroxialcanoatos , Aeromonas hydrophila/genética , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Halomonas/genética , Halomonas/metabolismo , Polihidroxialcanoatos/biosíntesis , Polihidroxialcanoatos/genéticaRESUMEN
Polyhydroxyalkanoates (PHA) composed of both short-chain-length (SCL) and medium-chain-length (MCL) monomers (SCL-co-MCL PHA) combine the advantages of high strength and elasticity provided by SCL PHA and MCL PHA, respectively. Synthesis of SCL-co-MCL PHA, namely, copolymers of 3-hydroxybutyrate (3HB) and MCL 3-hydroxyalkanoates (3HA) such as 3-hydroxydecanoate (3HD) and longer chain 3HA, has been a challenge for a long time. This study aims to engineer Pseudomonas entomophila for synthesizing P(3HB-co-MCL 3HA) via weakening its ß-oxidation pathway combined with insertion of 3HB synthesis pathway consisting of ß-ketothiolase (phaA) and acetoacetyl-CoA reductase (phaB). 3HB and MCL 3HA polymerization is catalyzed by a low specificity PHA synthase (phaC), namely, mutated PhaC61-3. The link between the fatty acid de novo synthesis and PHA synthesis was further blocked to increase the supply for SCL and MCL monomers in P. entomophila. The so-constructed P. entomophila was successfully used to synthesize novel PHA copolymers of P(3HB-co-3HD), P(3HB-co-3HDD) and P(3HB-co-3H9D) consisting of 3HB and 3-hydroxydecanoate (3HD), 3-hydroxydodecanoate (3HDD) and 3-hydroxy-9-decanent (3H9D), respectively. MCL 3HA compositions of P(3HB-co-3HD) and P(3HB-co-3HDD) can be adjusted from 0 to approximate 100â¯mol%. Results demonstrated that the engineered P. entomophila could be a platform for tailor-made P(3HB-co-MCL 3HA).
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Ácido 3-Hidroxibutírico/metabolismo , Aciltransferasas/genética , Aciltransferasas/metabolismo , Ingeniería Metabólica/métodos , Polihidroxialcanoatos/metabolismo , Polímeros/metabolismo , Pseudomonas/genética , Pseudomonas/metabolismo , Ácidos Grasos/metabolismo , Ácidos Grasos Volátiles/metabolismo , Técnicas de Inactivación de Genes , Peso Molecular , Oxidación-Reducción , Plásmidos/genéticaRESUMEN
Halomonas spp. are able to grow under a high salt concentration at alkali pH, they are able to resist contamination by other microbes. Development of Halomonas spp. as platform production strains for the next-generation industrial biotechnology (NGIB) is intensively studied. Among Halomonas spp., Halomonas bluephagenesis is the best studied one with available engineering tools and methods to reprogram it for production of various polyhydroxyalkanoates, proteins, and chemicals. Due to its contamination resistance, H. bluephagenesis can be grown under open and continuous processes not just in the labs but also in at least 1000 L fermentor scale. It is expected that NGIB based on Halomonas spp. be able to engineer for production of increasing number of products in a competitive manner.
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Halomonas/metabolismo , Microbiología Industrial/métodos , Ingeniería Metabólica/métodos , Biología Sintética/métodos , Proteínas Bacterianas/metabolismo , Vías Biosintéticas , Polihidroxialcanoatos/metabolismoRESUMEN
To engineer non-model organisms, suitable genetic parts must be available. However, biological parts are often host strain sensitive. It is therefore necessary to develop genetic parts that are functional regardless of host strains. Here we report several novel phage-derived expression systems used for transcriptional control in non-model bacteria. Novel T7-like RNA polymerase-promoter pairs were obtained by mining phage genomes, followed by in vivo characterization in non-model strains Halomonas spp TD01 and Pseudomonas entomophila. Three expression systems, namely, MmP1, VP4, and K1F, were developed displaying orthogonality (crosstalk<0.7%), tight regulation (3085-fold induction), and high efficiency (2.5-fold of Ptac) in Halomonas sp. TD01, a chassis strain with a high industrial value. The expression under the corresponding T7-like promoter libraries persisted with striking correlations (R2 >0.94) between Escherichia coli and Halomonas sp. TD01, implying suitability of broad-host range. Three Halomonas TD strains were then constructed based upon these expression systems that enabled interchangeable and controllable gene expression. One of the strains termed Halomonas TD-MmP1 was used to express the cell-elongation cassette (minCD genes) and polyhydroxybutyrate (PHB) biosynthetic pathway, resulting in a 100-fold increase in cell lengths and high levels of PHB production (up to 92% of cell dry weight), respectively. We envision these T7-like expression systems to benefit metabolic engineering in other non-model organisms.
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Bacteriófago T7/genética , Vectores Genéticos/genética , Halomonas/fisiología , Hidroxibutiratos/metabolismo , Ingeniería Metabólica/métodos , Transducción Genética/métodos , Proteínas Bacterianas/genética , Regulación Bacteriana de la Expresión Génica/genética , Halomonas/metabolismo , Redes y Vías Metabólicas/genéticaRESUMEN
The industrial production of low value-added biological products poses significant challenges due to cost pressures. In recent years, it has been argued that synthetic biology approaches will lead to breakthroughs that eliminate price bottlenecks for the production of a wide range of biological products including bioplastics and biofuels. One significant bottleneck lies in the necessity to break the tough cell walls of microbes in order to release intracellular products. We here report the implementation of the first synthetic biology standard part based on the lambda phage SRRz genes and a synthetic ribosome binding site (RBS) that works in Escherichia coli and Halomonas campaniensis, which enables the producer strains to induce lysis after the addition of small amounts (1-5 %) of solvents or to spontaneously lyse during the stresses of downstream processing, and thus has the potential to eliminate the mechanical cell disruption step as both an efficiency bottleneck and a significant capex barrier when implementing downstream bioprocesses.
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Autólisis , Bacteriólisis , Productos Biológicos/aislamiento & purificación , Biotecnología/métodos , Escherichia coli/metabolismo , Halomonas/metabolismo , Bacteriófago lambda/genética , Biotecnología/economía , Costos y Análisis de Costo , Escherichia coli/genética , Genes Virales , Halomonas/genéticaRESUMEN
Although the main genes in rice involved in the biosynthesis of secondary wall components have been characterized, the molecular mechanism underlying coordinated regulation of genes expression is not clear. In this study, we reported a new rice variety, cef1, showed the culm easily fragile (CEF) without other concomitant phenotypes. The CEF1 gene encodes a MYB family transcription factor OsMYB103L, was cloned based on map-based approach. Bioinformatics analyses indicated that CEF1 belongs to the R2R3-MYB subfamily and highly similar to Arabidopsis AtMYB103. Expression pattern analysis indicated that CEF1 is mainly expressed in internodes and panicles. Biochemical assays demonstrated that OsMYB103L is a nuclear protein and shows high transcriptional activation activity at C-terminus. OsMYB103L mediates cellulose biosynthesis and secondary walls formation mainly through directly binding the CESA4, CESA7, CESA9 and BC1 promoters and regulating their expression. OsMYB103L may also function as a master switch to regulate the expression of several downstream TFs, which involved in secondary cell wall biosynthesis. Furthermore, OsMYB103L physically interacts with SLENDER RICE1 (SLR1), a DELLA repressor of GA signaling, and involved in GA-mediated regulation of cellulose synthesis pathway. Our findings revealed that OsMYB103L plays an important role in GA-regulating secondary cell wall synthesis, and the manipulation of this gene provide a new strategy to help the straw decay in soil.
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Pared Celular/metabolismo , Genes de Plantas , Giberelinas/metabolismo , Oryza/genética , Oryza/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Celulosa/biosíntesis , Mapeo Cromosómico , Clonación Molecular , Regulación de la Expresión Génica de las Plantas , Fenotipo , Reguladores del Crecimiento de las Plantas/metabolismo , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estructura Terciaria de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transducción de Señal , Factores de Transcripción/química , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Técnicas del Sistema de Dos HíbridosRESUMEN
In this work, a series of Cu2Se/x wt % porous carbon (PC) (x = 0, 0.2, 0.4, 0.6, 0.8, 1) composite materials were synthesized by ball milling and spark plasma sintering (SPS). The highly ordered porous carbon was synthesized by a hydrothermal method using mesoporous silica (SBA-15) as the template. X-ray diffraction results show that the incorporation of porous carbon induces a phase transition of Cu2Se from the ß phase to the α phase. Meanwhile, the addition of porous carbon reduces the carrier concentration from 2.7 × 1021 to 2.45 × 1020 cm-3 by 1 order of magnitude. The decrease of the carrier concentration leads to the reduction of electrical conductivity and the increase of the Seebeck coefficient, which results in the enhancement of the power factor. On the other hand, the incorporation of porous carbon into Cu2Se increases the porosity of the composites and also introduces more interfaces between the two materials, which is evidenced by positron annihilation lifetime measurements. Both pores and interfaces greatly enhance phonon scattering, leading to extremely low lattice thermal conductivity. In addition, the decrease of electrical conductivity also causes a sufficient reduction in electronic thermal conductivity. Due to the above synergistic effects, the thermoelectric performance of the Cu2Se/PC composite is significantly enhanced with a maximum ZT value of 0.92 at 403 K in the Cu2Se/1 wt % PC composite, which is close to that of the Bi2Te3-based materials. Our work shows that α-Cu2Se has great potential for near-room-temperature thermoelectric materials.
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As a liquid-like material, CuAgSe has high carrier mobility and ultralow lattice thermal conductivity. It undergoes an n-p conduction-type transition during ß- to α-phase transition with increasing temperature. Moreover, optimization of the thermoelectric performance of CuAgSe is rather difficult, owing to the two-carrier conduction in this material. In this work, we reported the free tuning of the conduction type and thermoelectric performance of CuAgSe by manipulating the cation vacancies. Positron annihilation measurements reveal that the increase in CuAg content can effectively suppress the cation vacancies and reduce the hole carrier concentration, resulting in n-type conduction at high temperatures. Doping with Zn at the Cu sublattice in the CuAg-excessive CuAgSe can further decrease the number of vacancies, leading to a significant decrease in hole carrier concentration. Furthermore, the reduction of vacancies leads to weakening of carrier scattering. As a result, carrier mobility is also enhanced, thus improving the thermoelectric performance of n-type CuAgSe. On the other hand, high-performance p-type CuAgSe can be achieved by decreasing the CuAg content to introduce more cation vacancies. Ultimately, both n-type and p-type CuAgSe with superb thermoelectric performance are obtained, with a zTmax of 0.84 in Cu1.01Ag1.02Zn0.01Se (n-type) and 1.05 in (CuAg)0.96Se (p-type) at 600 K and average zT of 0.77 and 0.94 between 470 and 630 K for n-type and p-type, respectively.
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Next-generation sequencing (NGS) is emerging as a new method for the detection of clinically significant copy number variants (CNVs). In this study, we developed and validated rapid CNV-sequencing (rCNV-seq) for clinical application in prenatal diagnosis. Low-pass whole-genome sequencing was performed on PCR libraries prepared from amniocyte genomic DNA. From 10-40 ng of input DNA, PCR-free libraries consistently produced sequencing data with high unique read mapping ratios, low read redundancy, low coefficient of variation for all chromosomes and high genomic coverage. In validation studies, reliable and accurate CNV detection using PCR-free-based rCNV-seq was demonstrated for a range of common trisomies and sex chromosome aneuploidies as well as microdeletion and duplication syndromes. In reproducibility studies, CNV copy number and genomic intervals closely matched those defined by chromosome microarray analysis. Clinical testing of genomic DNA samples from 217 women referred for prenatal diagnosis identified eight samples (3.7%) with known chromosome disorders. We conclude that PCR-free-based rCNV-seq is a sensitive, specific, reproducible and efficient method that can be used in any NGS-based diagnostic laboratory for detection of clinically significant CNVs.
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Recent studies have demonstrated structural and functional alterations in Parkinson's disease (PD) with mild cognitive impairment (MCI). However, the topological patterns of functional brain networks in newly diagnosed PD patients with MCI are unclear so far. In this study, we used functional magnetic resonance imaging (fMRI) and graph theory approaches to explore the functional brain network in 45 PD patients with MCI (PD-MCI), 22 PD patients without MCI (PD-nMCI), and 18 healthy controls (HC). We found that the PD-MCI, PD-nMCI, and HC groups exhibited a small-world architecture in the functional brain network. However, early-stage PD-MCI patients had decreased clustering coefficient, increased characteristic path length, and changed nodal centrality in the default mode network (DMN), control network (CN), somatomotor network (SMN), and visual network (VN), which might contribute to factors for MCI symptoms in PD patients. Our results demonstrated that PD-MCI patients were associated with disrupted topological organization in the functional network, thus providing a topological network insight into the role of information exchange in the underlying development of MCI symptoms in PD patients.
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The status of T cell receptors (TCRs) repertoire is associated with the occurrence and progress of various diseases and can be used in monitoring the immune responses, predicting the prognosis of disease and other medical fields. High-throughput sequencing promotes the studying in TCR repertoire. The chapter focuses on the whole process of TCR profiling, including DNA extraction, library construction, high-throughput sequencing, and how to analyze data.
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Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Receptores de Antígenos de Linfocitos T/genética , Clonación Molecular/métodos , Regiones Determinantes de Complementariedad/genética , Biblioteca de Genes , Humanos , Receptores de Antígenos de Linfocitos T alfa-beta/genética , Linfocitos T/inmunología , Linfocitos T/fisiologíaRESUMEN
RATIONALE: Most gastric cancer patients are diagnosed at mid- to late-stage and lose the chance of radical surgery, medical treatment is especially important to prolong the survival of patients. Apatinib mesylate, which is a small molecule vascular endothelial growth factor receptor 2 tyrosine kinase inhibitor, could be used as antiangiogenesis therapy for gastric cancer. PATIENT CONCERNS: A 67-year-old man sought medical care for upper abdominal discomfort. DIAGNOSIS: The patient was diagnosed as mixed medullary differentiated gastric adenocarcinoma, and immunohistochemistry suggested HER-2 (2+). INTERVENTIONS: The patient received chemotherapy consisting of oxaliplatin combined with S-1 as first-line treatment, and targeted therapy with apatinib mesylate as second-line treatment. OUTCOMES: After 4 months of first-line chemotherapy, the patient received apatinib treatment immediately at a dose of 500âmg/d orally and died of cardiac arrest with 8.5 months of overall survival. During this period of targeted therapy with apatinib mesylate, this male patient suffered mammary gland development besides other common adverse reactions. LESSONS: This case report is the first to report the case of male mammary gland development after oral apatinib.
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Antineoplásicos/efectos adversos , Carcinoma Medular/tratamiento farmacológico , Glándulas Mamarias Humanas/efectos de los fármacos , Piridinas/efectos adversos , Neoplasias Gástricas/tratamiento farmacológico , Anciano , Humanos , MasculinoRESUMEN
For resectable cancer patients, a method that could precisely predict the risk of postoperative recurrence would be crucial for guiding adjuvant treatment. Since T cell receptor (TCR) repertoires had been shown to be closely related to the dynamics of cancers, here we enrolled a cohort of patients to evaluate the potential of TCR repertoires in predicting the prognosis of resectable non-small cell lung cancers. Specifically, TCRß repertoires were analyzed in surgical tumor tissues and matched adjacent non-tumor tissues from 39 patients enrolled with resectable non-small cell lung cancer, through target enrichment and high-throughput sequencing. As a result, there are significant differences between the TCR repertories of tumor samples and those of matched adjacent non-tumor samples as evaluated by criteria like the number of clonotypes. In addition, TCR repertoires were significantly associated with a few clinical features, as well as somatic mutations. Finally, certain TCRß variable-joining (V-J) pairings were featured to build a logistic regression model in predicting postoperative recurrence of resectable non-small cell lung cancers with a testing area under the receiver operating characteristic curve (AUC) of around 0.9. Thus, we hypothesize that TCR repertoires could be potentially used to predict prognosis after curative surgery for non-small cell lung cancer patients.
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OBJECTIVE: High-throughput sequencing based on copy number variation (CNV-seq) is commonly used to detect chromosomal abnormalities including aneuploidy. This study provides evidence for the prevalence of chromosomal abnormalities in target populations. METHODS: A total of 160 samples, including 83 high-risk pregnancies, 37 spontaneous abortions, and 40 suspected genetic disorders, were analyzed by CNV-seq. Relationships between the incidence of these chromosomal abnormalities and risk factors (e.g. advanced maternal age, abnormal pregnancy history, and family history of congenital disease) were further analyzed by subgroup. RESULTS: A total of 37 (44.6%) high-risk pregnancies, 25 (67.6%) spontaneous abortions, and 22 (55%) suspected genetic disorders had chromosomal abnormalities including aneuploidy and CNVs. There was an increased risk association between the prevalence of aneuploidy and pathogenic-relevant CNV in the fetus or abortive tissue and advanced maternal age. Moreover, a family history of congenital disease was also positively correlated with fetal chromosomal abnormalities in high-risk pregnancies. CONCLUSION: A relatively high prevalence of chromosomal abnormalities was detected in high-risk pregnancies, spontaneous abortions, and suspected genetic disorders, indicating the importance of CNV detection in such populations.
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Aborto Espontáneo/genética , Aberraciones Cromosómicas , Variaciones en el Número de Copia de ADN , Enfermedades Genéticas Congénitas/genética , Embarazo de Alto Riesgo/genética , Aborto Espontáneo/epidemiología , Adolescente , Adulto , China/epidemiología , Femenino , Estudios de Seguimiento , Enfermedades Genéticas Congénitas/epidemiología , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Cariotipificación , Embarazo , Prevalencia , Pronóstico , Adulto JovenRESUMEN
Phasins are unusual amphiphilic proteins that bind to microbial polyhydroxyalkanoate (PHA) granules in nature and show great potential for various applications in biotechnology and medicine. Despite their remarkable diversity, only the crystal structure of PhaPAh from Aeromonas hydrophila has been solved to date. Based on the structure of PhaPAh , homology models of PhaPAz from Azotobacter sp. FA-8 and PhaPTD from Halomonas bluephagenesis TD were successfully established, allowing rational mutagenesis to be conducted to enhance the stability and surfactant properties of these proteins. PhaPAz mutants, including PhaPAz Q38L and PhaPAz Q78L, as well as PhaPTD mutants, including PhaPTD Q38M and PhaPTD Q72M, showed better emulsification properties and improved thermostability (6-10°C higher melting temperatures) compared with their wild-type homologues under the same conditions. Importantly, the established PhaP homology-modelling approach, based on the high-resolution structure of PhaPAh , can be generalized to facilitate the study of other PhaP members.
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Aeromonas hydrophila/genética , Proteínas Bacterianas/genética , Lectinas de Plantas/genética , Polihidroxialcanoatos/metabolismo , Aeromonas hydrophila/química , Aeromonas hydrophila/metabolismo , Secuencia de Aminoácidos , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Datos de Secuencia Molecular , Mutagénesis , Lectinas de Plantas/química , Lectinas de Plantas/metabolismo , Estabilidad ProteicaRESUMEN
Poly(3-hydroxybutyrate-co-4-hydroxybutyrate), short as P(3HB-co-4HB), was successfully produced by engineered Halomonas bluephagenesis TD01 grown in glucose and γ-butyrolactone under open non-sterile conditions. Gene orfZ encoding 4HB-CoA transferase of Clostridium kluyveri was integrated into the genome to achieve P(3HB-co-4HB) accumulation comparable to that of strains encoding orfZ on plasmids. Fed-batch cultivations conducted in 1-L and 7-L fermentors, respectively, resulted in over 70g/L cell dry weight (CDW) containing 63% P(3HB-co-12mol% 4HB) after 48h under non-sterile conditions. The processes were further scaled up in a 1000-L pilot fermentor to reach 83g/L CDW containing 61% P(3HB-co-16mol% 4HB) in 48h, with a productivity of 1.04g/L/h, again, under non-sterile conditions. The elastic P(3HB-co-16mol% 4HB) shows an elongation at break of 1022±43%. Results demonstrate that the engineered Halomonas bluephagenesis TD01 is a suitable industrial strain for large scale production under open non-sterile conditions.
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Halomonas , Hidroxibutiratos , Poliésteres , Ácido 3-HidroxibutíricoRESUMEN
Coordination of shoot photosynthetic carbon fixation with root inorganic nitrogen uptake optimizes plant performance in a fluctuating environment [1]. However, the molecular basis of this long-distance shoot-root coordination is little understood. Here we show that Arabidopsis ELONGATED HYPOCOTYL5 (HY5), a bZIP transcription factor that regulates growth in response to light [2, 3], is a shoot-to-root mobile signal that mediates light promotion of root growth and nitrate uptake. Shoot-derived HY5 auto-activates root HY5 and also promotes root nitrate uptake by activating NRT2.1, a gene encoding a high-affinity nitrate transporter [4]. In the shoot, HY5 promotes carbon assimilation and translocation, whereas in the root, HY5 activation of NRT2.1 expression and nitrate uptake is potentiated by increased carbon photoassimilate (sucrose) levels. We further show that HY5 function is fluence-rate modulated and enables homeostatic maintenance of carbon-nitrogen balance in different light environments. Thus, mobile HY5 coordinates light-responsive carbon and nitrogen metabolism, and hence shoot and root growth, in a whole-organismal response to ambient light fluctuations.
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Proteínas de Transporte de Anión/genética , Proteínas de Arabidopsis/genética , Arabidopsis/fisiología , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/genética , Carbono/metabolismo , Regulación de la Expresión Génica de las Plantas , Nitrógeno/metabolismo , Proteínas Nucleares/genética , Proteínas de Transporte de Anión/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico/metabolismo , Proteínas Nucleares/metabolismo , Raíces de Plantas/metabolismo , Brotes de la Planta/metabolismo , Transducción de SeñalRESUMEN
Crop productivity is heavily dependent on the application of nitrogen (N) fertilizers. Increasing N fertilization levels, however, are subject to diminishing returns, quite apart from their deleterious impact on the environment. Improving N use efficiency (NUE) is therefore crucial for development of sustainable agriculture. Plant NUE is a complex trait determined by quantitative trait loci and influenced by environmental changes. The natural supply of soil N varies and is frequently limiting for plant growth and crop yield: unraveling the molecular basis of how plants sense and respond to changes in N availability should enable the development of new strategies to increase NUE. This review discusses the latest advances in our understanding of N signaling and crosstalk with other signaling pathways.