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With an eye toward expanding chemistries used for covalent ligand discovery, we elaborated an umpolung strategy that exploits the 'polarity reversal' of sulfur when cysteine is oxidized to sulfenic acid, a widespread post-translational modification, for selective bioconjugation with C-nucleophiles. Here we present a global map of a human sulfenome that is susceptible to covalent modification by members of a nucleophilic fragment library. More than 500 liganded sulfenic acids were identified on proteins across diverse functional classes, and, of these, more than 80% were not targeted by electrophilic fragment analogs. We further show that members of our nucleophilic fragment library can impair functional protein-protein interactions involved in nuclear oncoprotein transport and DNA damage repair. Our findings reveal a vast expanse of ligandable sulfenic acids in the human proteome and highlight the utility of nucleophilic small molecules in the fragment-based covalent ligand discovery pipeline, presaging further opportunities using non-traditional chemistries for targeting proteins.
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Cisteína , Ácidos Sulfênicos , Humanos , Cisteína/metabolismo , Ligantes , Proteoma/metabolismo , Processamento de Proteína Pós-TraducionalRESUMO
Cuprous oxide (Cu2O) nanoparticles (NPs) was anchored on wood by simple spraying method, then both soft and hard wood has been endowed efficient function photocatalytic degradation toward organic dyes and formaldehyde gas synergistically. The best recycle ability of wood based photocatalyst toward organic pollutants was achieved, which was characterized by photocatalytic degradation efficiency of methylene blue (MB) more than 95% after 100 cycles, and formaldehyde gas over 85% after 60 cycles. Cu2O NPs@wood performed much lower forbidden bandwidth (Eg), which accelerated to generate much more radical of e- and finally promoted the capacity of photocatalytic degradation. The proposed Cu2O NPs@wood catalysts has potential to be applied both in the field of wastewater and air pollution remediation.
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Nanopartículas , Madeira , Águas Residuárias , Corantes , FormaldeídoRESUMO
Red and blue light are the most important light spectra for driving photosynthesis to produce adequate crop yield. It is also believed that green light may contribute to adaptations to growth. However, the effects of green light, which can trigger specific and necessary responses of plant growth, have been underestimated in the past. In this study, lettuce (Lactuca sativa L.) was exposed to different continuous light (CL) conditions for 48 h by a combination of red and blue light-emitting diodes (LEDs) supplemented with or without green LEDs, in an environmental-controlled growth chamber. Green light supplementation enhanced photosynthetic capacity by increasing net photosynthetic rates, maximal photochemical efficiency, electron transport for carbon fixation (JPSII ) and chlorophyll content in plants under the CL treatment. Green light decreased malondialdehyde and H2 O2 accumulation by increasing the activities of superoxide dismutase (EC 1.15.1.1) and ascorbate peroxidase (EC 1.11.1.11) after 24 h of CL. Supplemental green light significantly increased the expression of photosynthetic genes LHCb and PsbA from 6 to 12 h, and these gene expressions were maintained at higher levels than those under other light conditions between 12 and 24 h. However, a notable downregulation of both LHCb and PsbA was observed during 24 to 48 h. These results indicate that the effects of green light on lettuce plant growth, via enhancing activity of particular components of antioxidative enzyme system and promoting of LHCb and PsbA expression to maintain higher photosynthetic capacity, alleviated a number of the negative effects caused by CL.
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Luz , Clorofila/metabolismo , Lactuca/metabolismo , Lactuca/efeitos da radiação , Fotossíntese/efeitos dos fármacos , Desenvolvimento Vegetal/efeitos da radiaçãoRESUMO
BACKGROUND: garlic reproduces mainly through clove planting, as sexual reproduction via seeds is uncommon. Growers encounter challenges with pathogens due to the larger size and vegetative nature of seed cloves, as well as the storage conditions conducive to fungal growth. Some Phyto-pathogenic fungi, previously unrecognized as garlic infections, can remain latent within bulb tissues long after harvest. Although outwardly healthy, these infected bulbs may develop rot under specific conditions. AIM OF REVIEW: planting diseased seed cloves can contaminate field soil, with some fungal and bacterial infections persisting for extended periods. The substantial size of seed cloves makes complete eradication of deeply ingrained infections difficult, despite the use of systemic fungicides during the preplanting and postharvest phases. Additionally, viruses, resistant to fungicides, persist in vegetative material. They are prevalent in much of the garlic used for planting, and their host vectors are difficult to eliminate. To address these challenges, tissue-culture techniques are increasingly employed to produce disease-free planting stock. Key scientific concepts of the review: garlic faces a concealed spectrum of diseases that pose a global challenge, encompassing fungal threats like Fusarium's vascular wilt and Alternaria's moldy rot, bacterial blights, and the elusive garlic yellow stripe virus. The struggle to eliminate deeply ingrained infections is exacerbated by the substantial size of seed cloves. Moreover, viruses persist in garlic seeds, spreading through carrier vectors, and remain unaffected by fungicides. This review emphasizes eco-friendly strategies to address these challenges, focusing on preventive measures, biocontrol agents, and plant extracts. Tissue-culture techniques emerge as a promising solution for generating disease-free garlic planting material. The review advocates for ongoing research to ensure sustainable garlic cultivation, recognizing the imperative of safeguarding this culinary staple from an array of fungal and viral threats.
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Anthocyanins, natural pigments known for their vibrant hues and beneficial properties, undergo intricate genetic control. However, red vegetables grown in plant factories frequently exhibit reduced anthocyanin synthesis compared to those in open fields due to factors like inadequate light, temperature, humidity, and nutrient availability. Comprehending these factors is essential for optimizing plant factory environments to enhance anthocyanin synthesis. This review insights the impact of physiological and genetic factors on the production of anthocyanins in red lettuce grown under controlled conditions. Further, we aim to gain a better understanding of the mechanisms involved in both synthesis and degradation of anthocyanins. Moreover, this review summarizes the identified regulators of anthocyanin synthesis in lettuce, addressing the gap in knowledge on controlling anthocyanin production in plant factories, with potential implications for various crops beyond red lettuce.
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Over 50 billion cells undergo apoptosis each day in an adult human to maintain immune homeostasis. Hydrogen sulfide (H2S) is also required to safeguard the function of immune response. However, it is unknown whether apoptosis regulates H2S production. Here, we show that apoptosis-deficient MRL/lpr (B6.MRL-Faslpr/J) and Bim-/- (B6.129S1-Bcl2l11tm1.1Ast/J) mice exhibit significantly reduced H2S levels along with aberrant differentiation of Th17 cells, which can be rescued by the additional H2S. Moreover, apoptotic cells and vesicles (apoVs) express key H2S-generating enzymes and generate a significant amount of H2S, indicating that apoptotic metabolism is an important source of H2S. Mechanistically, H2S sulfhydrates selenoprotein F (Sep15) to promote signal transducer and activator of transcription 1 (STAT1) phosphorylation and suppress STAT3 phosphorylation, leading to the inhibition of Th17 cell differentiation. Taken together, this study reveals a previously unknown role of apoptosis in maintaining H2S homeostasis and the unique role of H2S in regulating Th17 cell differentiation via sulfhydration of Sep15C38.
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Sulfeto de Hidrogênio , Adulto , Camundongos , Humanos , Animais , Sulfeto de Hidrogênio/farmacologia , Sulfeto de Hidrogênio/metabolismo , Células Th17 , Camundongos Endogâmicos MRL lpr , Diferenciação Celular , ApoptoseRESUMO
Hydrophobic carbon nanotubes are hardly to disperse in water and prone to agglomerate when poured with Copper Tailing-Based Cementitious Material (CTCM). Multi-walled carbon nanotubes (MWCNTs) + Arabic Gum (GA) dispersions were prepared by a novel method of synergistic optimization of concentration, controlling low-frequency ultrasonic time and setting the ambient temperature with non-toxic anionic surfactant GA as surfactant. The results of UV-Vis spectroscopy showed that the high stability MWCNTs + GA dispersion with low aggregation area (< 1.2%) and low aggregation beam size (< 219 nm) have been prepared by using 1.7 mmol/l GA. The effects of highly stable MWCNTs dispersion on the mechanical properties, microstructure and durability of CTCM were studied. The 28 days compressive strength increased by 21.5%, and the flexural strength increased by 20.5%, almost reaching the mechanical level of the control group. The results of SEM, XRD and EDS showed that GA significantly enhanced the dispersion of MWCNT in aqueous solution at a suitable concentration (mass ratio of GA:CNTs = 1:1). The microstructure of the prepared CTCM by high stability MWCNTs dispersion was optimized obviously, and the mechanical properties and durability were improved significantly. This method solves the dual problem of MWCNTs not being fully dispersed in aqueous solution and being easily re-agglomerated in cementitious materials, as well as finding a breakthrough for the low cost and industrialization of tailings cement-based composite cementitious materials.
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Adult rats chronic unpredictable stress model of depression (CUS) was adopted to elucidate the antidepressant pharmacological activity and related neurogenesis protective effect of the total flavonoids extract (licorice flavonoids, LF) from the Glycyrrhiza uralensis Fisch. cultivated locally in Ningxia. The rats were exposed to 9 kinds of unpredictable sequence of stressors and were given flavonoids (300 mg x kg(-1), 100 mg x kg(-1) and 30 mg x kg(-1)) for 28 days. The antidepressant effect was elucidated by open field test, forced swimming test and tail suspension test. The level of serum corticosterone was detected by radioimmunoassay. 5'-Bromo-2'-deoxyuridine (BrdU) labeling experiments was employed to study the neurogenesis protective activities. The flavonoids can increase the sum of line crosses and number of rears, and decrease the number of fecal boli produced in the open field test of the CUS rats. Also the flavonoids can decrease the immobility time in forced swim test as well as in the tail suspension test. In addition, the flavonoids (300 mg x kg(-1)) can decrease the serum corticosterone level of the CUS rats, and increase the number of the new born BrdU positive progenitor cells at the subgranular zone (SGZ) of dentate gyrus (DG) region in hippocampus. The results demonstrated that the total flavonoids extract from the cultivated Glycyrrhiza uralensis Fisch. could produce the anti-depressive effect on chronic unpredictable stress of depression model rats and its mechanism may be associated with its neurogenesis protective effect.
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Antidepressivos/farmacologia , Flavonoides/farmacologia , Glycyrrhiza uralensis/química , Neurogênese/efeitos dos fármacos , Estresse Psicológico , Animais , Antidepressivos/isolamento & purificação , Comportamento Animal/efeitos dos fármacos , Bromodesoxiuridina/metabolismo , Corticosterona/metabolismo , Depressão/metabolismo , Depressão/fisiopatologia , Flavonoides/isolamento & purificação , Elevação dos Membros Posteriores , Hipocampo/citologia , Hipocampo/metabolismo , Masculino , Plantas Medicinais/química , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Estresse Psicológico/metabolismo , Estresse Psicológico/fisiopatologia , NataçãoRESUMO
Raising young plants is important for modern greenhouse production. Upon transfer from the raising to the production environment, young plants should maximize light use efficiency while minimizing deleterious effects associated with exposure to high light (HL) intensity. The light spectrum may be used to establish desired traits, but how plants acclimated to a given spectrum respond to HL intensity exposure is less well explored. Cucumber (Cucumis sativus) seedlings were grown in a greenhouse in low-intensity sunlight (control; â¼2.7 mol photons m-2 day-1) and were treated with white, red, blue, or green supplemental light (4.3 mol photons m-2 day-1) for 10 days. Photosynthetic capacity was highest in leaves treated with blue light, followed by white, red, and green, and was positively correlated with leaf thickness, nitrogen, and chlorophyll concentration. Acclimation to different spectra did not affect the rate of photosynthetic induction, but leaves grown under blue light showed faster induction and relaxation of non-photochemical quenching (NPQ) under alternating HL and LL intensity. Blue-light-acclimated leaves showed reduced photoinhibition after HL intensity exposure, as indicated by a high maximum quantum yield of photosystem II photochemistry (F v /F m ). Although plants grown under different supplemental light spectra for 10 days had similar shoot biomass, blue-light-grown plants (B-grown plants) showed a more compact morphology with smaller leaf areas and shorter stems. However, after subsequent, week-long exposure to full sunlight (10.7 mol photons m-2 day-1), B-grown plants showed similar leaf area and 15% higher shoot biomass, compared to plants that had been acclimated to other spectra. The faster growth rate in blue-light-acclimated plants compared to other plants was mainly due to a higher photosynthetic capacity and highly regulated NPQ performance under intermittent high solar light. Acclimation to blue supplemental light can improve light use efficiency and diminish photoinhibition under high solar light exposure, which can benefit plant growth.
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Green light, as part of the photosynthetically active radiation, has been proven to have high photosynthetic efficiency once absorbed by plant leaves and can regulate plant physiological activities. However, few studies have investigated the appropriate and efficient way of using the green light for plant production. Thus, the objective of this study was to investigate a moderate amount of green light, partially replacing red and blue light, for plant growth and development. In this experiment, four treatments were set up by adjusting the relative amount of green light as 0 (RB), 30 (G30), 60 (G60), and 90 (G90) µmol m-2 s-1, respectively, with a total photosynthetic photon flux density of 200 µmol m-2 s-1 and a fixed red-to-blue ratio of 4:1. Lettuce (Lactuca sativa cv. 'Tiberius') plant growth and morphology, stomatal characteristics, light absorptance and transmittance, photosynthetic characteristics, and nutritional quality were investigated. The results showed that: (1) shoot dry weight increased by 16.3 and 24.5% and leaf area increased by 11.9 and 16.2% under G30 and G60, respectively, compared with those under RB. Plant stem length increased linearly with increasing green-to-blue light ratio; (2) light transmittance of lettuce leaf under treatments employing green light was higher than that under RB, especially in the green region; (3) stomatal density increased, whereas stomatal aperture area decreased with the increase in the relative amount of green light; and (4) carbohydrate accumulation increased under G60 and G90. Soluble sugar contents under G60 and G90 increased by 39.4 and 19.4%, respectively. Nitrate contents under G30, G60, and G90 decreased by 26.2, 40.3, and 43.4%, respectively. The above results indicated that 15-30% green light replacing red and blue light effectively increased the yield and nutritional quality of lettuce plants.
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Excessive accumulation of nitrates in vegetables is a common issue that poses a potential threat to human health. The absorption, translocation, and assimilation of nitrates in vegetables are tightly regulated by the interaction of internal cues (expression of related genes and enzyme activities) and external environmental factors. In addition to global food security, food nutritional quality is recognized as being of strategic importance by most governments and other agencies. Therefore, the identification and development of sustainable, innovative, and inexpensive approaches for increasing vegetable production and concomitantly reducing nitrate concentration are extremely important. Under controlled environmental conditions, optimal fertilizer/nutrient element management and environmental regulation play vital roles in producing vegetables with low nitrate content. In this review, we present some of the recent findings concerning the effects of environmental factors (e.g., light, temperature, and CO2) and fertilizer/nutrient solution management strategies on nitrate reduction in vegetables grown under controlled environments and discuss the possible molecular mechanisms. We also highlight several perspectives for future research to optimize the yield and nutrition quality of leafy vegetables grown in controlled environments.