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1.
Int J Mol Sci ; 25(12)2024 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-38928379

RESUMO

Stylo (Stylosanthes spp.) is an important pasture legume with strong aluminum (Al) resistance. However, the molecular mechanisms underlying its Al tolerance remain fragmentary. Due to the incomplete genome sequence information of stylo, we first conducted full-length transcriptome sequencing for stylo root tips treated with and without Al and identified three Snakin/GASA genes, namely, SgSnakin1, SgSnakin2, and SgSnakin3. Through quantitative RT-PCR, we found that only SgSnakin1 was significantly upregulated by Al treatments in stylo root tips. Histochemical localization assays further verified the Al-enhanced expression of SgSnakin1 in stylo root tips. Subcellular localization in both tobacco and onion epidermis cells showed that SgSnakin1 localized to the cell wall. Overexpression of SgSnakin1 conferred Al tolerance in transgenic Arabidopsis, as reflected by higher relative root growth and cell vitality, as well as lower Al concentration in the roots of transgenic plants. Additionally, overexpression of SgSnakin1 increased the activities of SOD and POD and decreased the levels of O2·- and H2O2 in transgenic Arabidopsis in response to Al stress. These findings indicate that SgSnakin1 may function in Al resistance by enhancing the scavenging of reactive oxygen species through the regulation of antioxidant enzyme activities.


Assuntos
Alumínio , Arabidopsis , Regulação da Expressão Gênica de Plantas , Proteínas de Plantas , Plantas Geneticamente Modificadas , Espécies Reativas de Oxigênio , Alumínio/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Arabidopsis/metabolismo , Arabidopsis/genética , Arabidopsis/efeitos dos fármacos , Fabaceae/metabolismo , Fabaceae/genética , Fabaceae/efeitos dos fármacos , Raízes de Plantas/metabolismo , Raízes de Plantas/efeitos dos fármacos , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/genética , Peróxido de Hidrogênio/metabolismo , Nicotiana/genética , Nicotiana/metabolismo , Nicotiana/efeitos dos fármacos
2.
J Pharm Pharmacol ; 76(7): 897-907, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38727186

RESUMO

OBJECTIVES: Bile acids (BAs), as signaling molecules to regulate metabolism, have received considerable attention. Genipin is an iridoid compound extracted from Fructus Gradeniae, which has been shown to relieve adiposity and metabolic syndrome. Here, we investigated the mechanism of genipin counteracting obesity and its relationship with BAs signals in diet-induced obese (DIO) rats. METHODS: The DIO rats were received intraperitoneal injections of genipin for 10 days. The body weight, visceral fat, lipid metabolism in the liver, thermogenic genes expressions in brown fat, BAs metabolism and signals, and key enzymes for BAs synthesis were determined. KEY FINDINGS: Genipin inhibited fat synthesis and promoted lipolysis in the liver, and upregulated thermogenic gene expressions in brown adipose tissue of DIO rats. Genipin increased bile flow rate and upregulated the expressions of aquaporin 8 and the transporters of BAs in liver. Furthermore, genipin changed BAs composition by promoting alternative pathways and inhibiting classical pathways for BAs synthesis and upregulated the expressions of bile acid receptors synchronously. CONCLUSIONS: These results suggest that genipin ameliorate obesity through BAs-mediated signaling pathways.


Assuntos
Ácidos e Sais Biliares , Iridoides , Fígado , Obesidade , Ratos Sprague-Dawley , Animais , Obesidade/tratamento farmacológico , Obesidade/metabolismo , Iridoides/farmacologia , Ácidos e Sais Biliares/metabolismo , Masculino , Ratos , Fígado/metabolismo , Fígado/efeitos dos fármacos , Metabolismo dos Lipídeos/efeitos dos fármacos , Dieta Hiperlipídica/efeitos adversos , Bile/metabolismo , Transdução de Sinais/efeitos dos fármacos , Lipólise/efeitos dos fármacos , Gordura Intra-Abdominal/efeitos dos fármacos , Gordura Intra-Abdominal/metabolismo
3.
Int J Biol Macromol ; 270(Pt 1): 132295, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38735615

RESUMO

Ovomucin-Complex extracted from egg white is expected to have a barrier function similar to gastric mucin. In this study, the dynamic changes in structure, rheological properties and binding ability of Ovomucin-Complex during in vitro simulated gastric digestion were investigated. The results from HPLC and CLSM showed that extremely acidic pH (pH = 2.0) promoted Ovomucin-Complex to form aggregation. Acid-induced aggregation may hinder its binding to pepsin, thus rendering Ovomucin-Complex resistant to pepsin. Consequently, most of the polymer structure and weak gel properties of Ovomucin-Complex retained after simulated gastric digestion as verified by HPLC, CLSM and rheological measurement, although there was a small breakdown of the glycosidic bond as confirmed by the increased content of reducing sugar. The significantly reduced hydrophobic interactions of Ovomucin-Complex were observed under extremely acidic conditions and simulated gastric digestion compared with the native. Noticeably, the undigested Ovomucin-Complex after simulated gastric digestion showed a higher affinity (KD = 5.0 ± 3.2 nm) for urease - the key surface antigen of Helicobacter pylori. The interaction mechanism between Ovomucin-Complex and urease during gastric digestion deserves further studies. This finding provides a new insight to develop an artificial physical mucus barrier to reduce Helicobacter pylori infection.


Assuntos
Digestão , Ovomucina , Urease , Urease/metabolismo , Urease/química , Ovomucina/química , Ovomucina/metabolismo , Concentração de Íons de Hidrogênio , Ligação Proteica , Pepsina A/metabolismo , Pepsina A/química , Polimerização , Helicobacter pylori , Reologia , Humanos
4.
Cognition ; 249: 105808, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38776622

RESUMO

This study aimed to determine the unit for switching representational states in visual working memory (VWM). Two opposing hypotheses were investigated: (a) the unit of switching being a feature (feature-based hypothesis), and (b) the unit of switching being an object (object-based hypothesis). Participants (N = 180) were instructed to hold two features from either one or two objects in their VWM. The memory-driven attentional capture effect, suggesting that actively held information in VWM can cause attention to be drawn towards matched distractors, was employed to assess representational states of the first and second probed colors (indicated by a retro-cue). The results showed that only the feature indicated to be probed first could elicit memory related capture for the condition of separate objects. Importantly, features from an integrated object could guide attention regardless of the probe order. These findings were observed across three experiments involving features of different dimensions, same dimensions, or perceptual objects defined by Gestalt principles. They provide convergent evidence supporting the object-based hypothesis by indicating that features within a single object cannot exist in different states.


Assuntos
Atenção , Memória de Curto Prazo , Percepção Visual , Humanos , Memória de Curto Prazo/fisiologia , Masculino , Atenção/fisiologia , Feminino , Adulto Jovem , Adulto , Percepção Visual/fisiologia , Tempo de Reação/fisiologia , Estimulação Luminosa , Adolescente , Percepção de Cores/fisiologia
5.
Artigo em Inglês | MEDLINE | ID: mdl-38551426

RESUMO

Context: Mortality from severe sepsis has been declining in recent years but remains a challenge worldwide because it remains the most frequent cause of death in ICUs. High-quality nursing care during a patient's CBP can play an important role in promoting a patient's physical condition. Objective: The study intended to explore the effects of nursing based on a humanistic care concept on continuous blood purification (CBP) treatment for patients with severe sepsis in an intensive care unit (ICU). Design: The research team performed a prospective randomized controlled study. Setting: The study took place at Minhang Hospital at Fudan University in Shanghai, China. Participants: Participants were 80 patients with severe sepsis who had been admitted to the ICU of the hospital and who were receiving CBP between April 2021 and December 2022. Intervention: The research team randomly divided participants into two groups according to their admission sequence, with 40 participants in each group: (1) an intervention group, the humanistic care group, who received CBP under humanistic care, and (2) a control group who received CBP under routine nursing. Outcome Measures: At baseline and postintervention, the research team: (1) measured participants' negative emotions using the Self-rating Anxiety Scale (SAS) and the Self-rating Depression scale (SDS), (2) assessed participants' hope levels using the Herth Hope Index (HHI), and (3) evaluated participants' health statuses using the Acute Physiology and Chronic Health Evaluation (APACHE-II). The team also measured the complication rate and determined participants' treatment compliance. Results: Postintervention compared to the control group, the humanistic care group's: (1) SAS and SDS scores were significantly lower, with P < .001 and P < .001, respectively; (2) HHI score was significantly higher, with P < .001; (3) APACHE-II scores and complication rate were significantly lower, with P < .001 and < .001, respectively; and (4) treatment compliance was significantly higher, with P = .0186. Conclusions: Nursing based on a humanistic care concept in ICUs can effectively alleviate the negative mood of patients with severe sepsis receiving CBP, enhance their hope levels and the treatment effect, improve their health statuses and treatment compliance, and reduce the occurrence of complications.

6.
BMC Cardiovasc Disord ; 24(1): 9, 2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38166759

RESUMO

BACKGROUND: The difference in the long-term outcomes of myocardial infarction in patients with non-obstructed coronary arteries (MINOCA) and patients with myocardial infarction with obstructed coronary artery disease (MI-CAD) is not clear. The current study aimed to pool adjusted data to compare long-term outcomes of MINOCA vs MI-CAD. METHODS: Electronic literature search of PubMed, Embase, CENTRAL, and Google Scholar databases was done for publications up to 18th June 2023. Only studies reporting multivariable-adjusted data with > 1 year of follow-up were included. RESULTS: Sixteen studies met the inclusion criteria. Our meta-analysis revealed no statistically significant difference in the risk of all-cause mortality between MINOCA and MI-CAD patients (HR: 0.90 95% CI 0.68, 1.19 I2 = 94% p = 0.48). Analysis of the limited data showed a reduced combined risk of all-cause mortality and MI (HR: 0.54 95% CI 0.39, 0.76 I2 = 72% p = 0.003) and major adverse cardiac events (MACE) (HR: 0.66 95% CI 0.51, 0.84 I2 = 51% p = 0.0009) in patients with MINOCA vs MI-CAD, and no difference in the risk of cardiovascular mortality (HR: 0.81 95% CI 0.54, 1.22 I2 = 0% p = 0.31) and readmission between the two groups (HR: 0.85 95% CI 0.61, 1.19 I2 = 90% p = 0.35). CONCLUSION: A pooled analysis of adjusted outcomes from the available studies indicated that MINOCA and MI-CAD patients have similar long-term all-cause mortality risk. Our conclusions on the risk of cardiovascular mortality, MACE and readmission rates need to be taken with caution due to a lack of adequate studies. Further research is needed to strengthen the evidence on this important subject.


Assuntos
Doença da Artéria Coronariana , Infarto do Miocárdio , Humanos , Doença da Artéria Coronariana/diagnóstico por imagem , Doença da Artéria Coronariana/complicações , MINOCA , Angiografia Coronária/efeitos adversos , Vasos Coronários , Fatores de Risco , Prognóstico
7.
Heliyon ; 10(1): e23336, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38205320

RESUMO

Aims: Excessive alcohol consumption can lead to alcoholic liver diseases (ALDs). Tetrastigma hemsleyanum Diels et Gilg is a rare Chinese medicinal herb. Tetrastigma hemsleyanum Diels et Gilg has been validated to be highly effective for treating hepatitis. Kaempferol and nicotiflorin are two highly representative flavonoids, which have exhibit therapeutic effects on liver disease. Therefore, the protective mechanism of kaempferol and nicotiflorin on alcohol-induced liver injury were investigated. Main methods: Forty mice were used in this study. After treatment of Kaempferol and nicotiflorin, serum and liver were collected and used for determination of biochemical indicators, H&E staining, and molecular detection. The interaction of miRNAs from serum extracellular vehicles (EVs) with mRNAs and 16S rRNA sequencing of gut microbiota were also investigated. Key findings: The results showed that kaempferol and nicotiflorins significantly ameliorated alcohol-induced liver damage and observably regulated gut microbiota. Specifically, the levels of malondialdehyde (MDA) and CYP2E1 in the liver significantly reduced, and the activity of superoxide dismutase (SOD) and glutathione (GSH) in the liver evidently increased. They also significantly relieved liver oxidative stress and lipid accumulation by suppressing miR-138-5p expression, inversely enhancing deacetylase silencing information regulator 2 related enzyme-1 (SIRT1) levels and then decreasing farnesoid X receptor (FXR) acetylation, which then modulated Nrf2 and SREBP-1c signaling pathways to regulate oxidative stress and lipid metabolism induced by alcohol. Significance: Kaempferol and nicotiflorin reduced alcohol-induced liver damage by enhancing alcohol metabolism and reducing oxidative stress and lipid metabolism. The intestinal microorganism disorder was also ameliorated after oral kaempferol and nicotiflorin.

8.
BMC Plant Biol ; 24(1): 68, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38262956

RESUMO

BACKGROUND: Papaya (Carica papaya) is an economically important fruit cultivated in the tropical and subtropical regions of China. However, the rapid softening rate after postharvest leads to a short shelf-life and considerable economic losses. Accordingly, understanding the mechanisms underlying fruit postharvest softening will be a reasonable way to maintain fruit quality and extend its shelf-life. RESULTS: Mitogen-activated protein kinases (MAPKs) are conserved and play essential roles in response to biotic and abiotic stresses. However, the MAPK family remain poorly studied in papaya. Here, a total of nine putative CpMAPK members were identified within papaya genome, and a comprehensive genome-wide characterization of the CpMAPKs was performed, including evolutionary relationships, conserved domains, gene structures, chromosomal locations, cis-regulatory elements and expression profiles in response to phytohormone and antioxidant organic compound treatments during fruit postharvest ripening. Our findings showed that nearly all CpMAPKs harbored the conserved P-loop, C-loop and activation loop domains. Phylogenetic analysis showed that CpMAPK members could be categorized into four groups (A-D), with the members within the same groups displaying high similarity in protein domains and intron-exon organizations. Moreover, a number of cis-acting elements related to hormone signaling, circadian rhythm, or low-temperature stresses were identified in the promoters of CpMAPKs. Notably, gene expression profiles demonstrated that CpMAPKs exhibited various responses to 2-chloroethylphosphonic acid (ethephon), 1-methylcyclopropene (1-MCP) and the combined ascorbic acid (AsA) and chitosan (CTS) treatments during papaya postharvest ripening. Among them, both CpMAPK9 and CpMAPK20 displayed significant induction in papaya flesh by ethephon treatment, and were pronounced inhibition after AsA and CTS treatments at 16 d compared to those of natural ripening control, suggesting that they potentially involve in fruit postharvest ripening through ethylene signaling pathway or modulating cell wall metabolism. CONCLUSION: This study will provide some valuable insights into future functional characterization of CpMAPKs, and hold great potential for further understanding the molecular mechanisms underlying papaya fruit postharvest ripening.


Assuntos
Carica , Quitosana , Ciclopropanos , Compostos Organofosforados , Frutas , Filogenia , Ácido Ascórbico
9.
Biol Chem ; 405(4): 267-281, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38081222

RESUMO

Celastrol (Cel) shows potent antitumor activity in various experimental models. This study examined the relationship between Cel's antivascular and antitumor effects and sphingolipids. CCK-8 assay, transwell assay, Matrigel, PCR-array/RT-PCR/western blotting/immunohistochemistry assay, ELISA and HE staining were used to detect cell proliferation, migration and invasion, adhesion and angiogenesis, mRNA and protein expression, S1P production and tumor morphology. The results showed that Cel could inhibit proliferation, migration or invasion, adhesion and angiogenesis of human umbilical vein endothelial cells (HUVECs) and MDA-MB-231 cells by downregulating the expression of degenerative spermatocyte homolog 1 (DEGS1). Transfection experiments showed that downregulation of DEGS1 inhibited the above processes and sphingosine-1-phosphate (S1P) production of HUVECs and MDA-MB-231 cells, while upregulation of DEGS1 had the opposite effects. Coculture experiments showed that HUVECs could promote proliferation, migration and invasion of MDA-MB-231 cells through S1P/sphingosine-1-phosphate receptor (S1PR) signaling pathway, while Cel inhibited these processes in MDA-MB-231 cells induced by HUVECs. Animal experiments showed that Cel could inhibit tumor growth in nude mice. Western blotting, immunohistochemistry and ELISA assay showed that Cel downregulated the expression of DEGS1, CD146, S1PR1-3 and S1P production. These data confirm that DEGS1/S1P signaling pathway may be related to the antivascular and antitumor effects of cel.


Assuntos
Fenômenos Biológicos , Triterpenos Pentacíclicos , Receptores de Lisoesfingolipídeo , Esfingosina/análogos & derivados , Camundongos , Animais , Humanos , Receptores de Lisoesfingolipídeo/genética , Receptores de Lisoesfingolipídeo/metabolismo , Células MDA-MB-231 , Angiogênese , Camundongos Nus , Transdução de Sinais , Células Endoteliais da Veia Umbilical Humana/metabolismo , Esfingosina/farmacologia , Esfingosina/metabolismo , Lisofosfolipídeos/farmacologia , Lisofosfolipídeos/metabolismo
10.
Plant Cell Environ ; 47(1): 259-277, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37691629

RESUMO

Phosphorus (P) is an essential nutrient, but easily fixed in soils. Therefore, most of soil P exists in the form of inaccessible organic phosphorus (Po), particularly phytate-P. Root-associated purple acid phosphatases (PAPs) are considered to play a crucial role in phosphate (Pi) scavenging in soils. However, evidence for regulating root-associated PAPs in utilization of extracellular phytate-P remain largely unknown in plants at both transcriptional and posttranslational levels. In this study, a Pi-starvation responsive GmPAP15a was identified in soybean (Glycine max). Overexpressing GmPAP15a led to significant increases in root-associated phytase activities, as well as total P content when phytate-P was supplied as the sole P resource in soybean hairy roots. Meanwhile, mass spectrometry (MS) analysis showed GmPAP15a was glycosylated at Asn144 and Asn502 , and its glycan structures of N-linked oligosaccharide chains exhibited microheterogeneity. Moreover, two homologues of AtPHR1, GmPHR9 and GmPHR32 were found to activate GmPAP15a transcription through luciferase activity analysis. Taken together, it is strongly suggested that GmPAP15a plays a vital role in phytate-P utilization in soybean, which might be regulated at both transcriptional and glycosylation modification levels. Our results highlight the GmPHR9/GmPHR32-GmPAP15a signalling pathway might present, and control phytate-P utilization in soybean.


Assuntos
Glycine max , Ácido Fítico , Glycine max/metabolismo , Glicosilação , Ácido Fítico/metabolismo , Proteínas de Plantas/metabolismo , Raízes de Plantas/metabolismo , Fósforo/metabolismo , Solo
11.
Cell Rep ; 42(11): 113406, 2023 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-37952153

RESUMO

Niacin, an age-old lipid-lowering drug, acts through the hydroxycarboxylic acid receptor 2 (HCAR2), a G-protein-coupled receptor (GPCR). Yet, its use is hindered by side effects like skin flushing. To address this, specific HCAR2 agonists, like MK-6892 and GSK256073, with fewer adverse effects have been created. However, the activation mechanism of HCAR2 by niacin and these new agonists is not well understood. Here, we present three cryoelectron microscopy structures of Gi-coupled HCAR2 bound to niacin, MK-6892, and GSK256073. Our findings show that different ligands induce varying binding pockets in HCAR2, influenced by aromatic amino acid clusters (W91ECL1, H1614.59, W1885.38, H1895.39, and F1935.43) from receptors ECL1, TM4, and TM5. Additionally, conserved residues R1113.36 and Y2847.43, unique to the HCA receptor family, likely initiate activation signal propagation in HCAR2. This study provides insights into ligand recognition, receptor activation, and G protein coupling mediated by HCAR2, laying the groundwork for developing HCAR2-targeted drugs.


Assuntos
Ácidos Cicloexanocarboxílicos , Niacina , Humanos , Niacina/farmacologia , Microscopia Crioeletrônica , Receptores Acoplados a Proteínas G/metabolismo , Ligantes , Lipídeos
12.
Nature ; 620(7974): 676-681, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37532940

RESUMO

Phosphorylation of G-protein-coupled receptors (GPCRs) by GPCR kinases (GRKs) desensitizes G-protein signalling and promotes arrestin signalling, which is also modulated by biased ligands1-6. The molecular assembly of GRKs on GPCRs and the basis of GRK-mediated biased signalling remain largely unknown owing to the weak GPCR-GRK interactions. Here we report the complex structure of neurotensin receptor 1 (NTSR1) bound to GRK2, Gαq and the arrestin-biased ligand SBI-5537. The density map reveals the arrangement of the intact GRK2 with the receptor, with the N-terminal helix of GRK2 docking into the open cytoplasmic pocket formed by the outward movement of the receptor transmembrane helix 6, analogous to the binding of the G protein to the receptor. SBI-553 binds at the interface between GRK2 and NTSR1 to enhance GRK2 binding. The binding mode of SBI-553 is compatible with arrestin binding but clashes with the binding of Gαq protein, thus providing a mechanism for its arrestin-biased signalling capability. In sum, our structure provides a rational model for understanding the details of GPCR-GRK interactions and GRK2-mediated biased signalling.


Assuntos
Quinase 2 de Receptor Acoplado a Proteína G , Receptores Acoplados a Proteínas G , Transdução de Sinais , Arrestinas/metabolismo , Fosforilação , Receptores Acoplados a Proteínas G/metabolismo , Quinase 2 de Receptor Acoplado a Proteína G/biossíntese , Quinase 2 de Receptor Acoplado a Proteína G/química , Quinase 2 de Receptor Acoplado a Proteína G/metabolismo , Subunidades alfa Gq-G11 de Proteínas de Ligação ao GTP/metabolismo , Ligantes , Ligação Proteica , Receptores de Neurotensina/metabolismo
14.
Parasit Vectors ; 16(1): 88, 2023 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-36879311

RESUMO

BACKGROUND: Most haematophagous organisms constantly suck the host's haemoglobin, which produces toxic free haem. This toxic haem aggregation into the nontoxic crystallisation complex known as haemozoin represents one of the most important detoxification pathways in living organisms, but very little is known about the features of haemozoin in parasitic nematodes. Here, we identified and characterised the haemozoin of an economically significant blood-sucking nematode, Haemonchus contortus. METHODS: Using electron microscopy, spectrophotometry analyses and biochemical approaches, haemozoin crystallisation was identified and characterised in parasitic fourth-stage larvae (L4s) and/or adult worms as well as L4s of in vitro culture. RESULTS: The haemozoin was formed in intestinal lipid droplets of the parasitic L4s and adult worms. The characterisation of the haemozoin showed regularly spherical structures and had a 400-nm absorption peak. Furthermore, the haemozoin in in vitro cultured L4s was associated with the culture time and concentration of red blood cells added into the medium, and its formation could be inhibited by chloroquine-derived drugs. CONCLUSIONS: This work provides detailed insight into the haemozoin formation of H. contortus and should have important implications for developing novel therapeutic targets against this parasite or related haematophagous organisms.


Assuntos
Haemonchus , Hemeproteínas , Animais , Cloroquina , Heme
15.
Bioresour Technol ; 377: 128931, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36940883

RESUMO

Bacterial immobilization is a common method in anaerobic fermentation, since of the maintenance of high bacterial activity, insurance of high density microbial during continuous fermentation, and quick adaptability to the environment. While, the bio-hydrogen production capacity of immobilized photosynthetic bacteria (I-PSB) is seriously affected by the low light transfer efficiency. Hence, in this study, photo-catalytic nano-particles (PNPs) was added into the photo-fermentative bio-hydrogen production (PFHP) system, and its enhancement effects of bio-hydrogen production performance were investigated. Results showed that the maximum cumulative hydrogen yield (CHY) of I-PSB with 100 mg/L nano-SnO2 (154.33 ± 7.33 mL) addition was 18.54% and 33.06% higher than those of I-PSB without nano-SnO2 addition and control group (free cells), and the lag time was the shortest indicating a shorter cell arrest time, more cells and faster response. Maximum energy recovery efficiency and light conversion efficiency were also found to be increased by 18.5% and 12.4%, respectively.


Assuntos
Bactérias , Hidrogênio , Fermentação , Concentração de Íons de Hidrogênio
16.
Bioresour Technol ; 375: 128814, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36868428

RESUMO

In this study, corncob was taken as substrate, the co-production process of biohydrogen and biofertilizer by photo-fermentation was investigated and its carbon footprint analysis was conducted to evaluate the carbon transfer pathway. Biohydrogen was produced by photo-fermentation, and the hydrogen producing residues were immobilized by sodium alginate. Cumulative hydrogen yield (CHY) and nitrogen release ability (NRA) was taken as references, and the effect of substrate particle size on the co-production process was evaluated. Results showed that due to the porous adsorption properties, corncob size of 120 mesh was the optimal one. Under that condition, the highest CHY and NRA were 71.16 mL/g TS and 68.76%, respectively. The carbon footprint analysis indicted that 7.9% carbon element was released as carbon dioxide, 78.3% carbon element was immobilized in the biofertilizer, and 13.8% carbon element was lost. This work is significant of the biomass utilization and clean energy production.


Assuntos
Pegada de Carbono , Zea mays , Fermentação , Zea mays/metabolismo , Hidrogênio/metabolismo
17.
Nat Commun ; 14(1): 1268, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36882417

RESUMO

Endothelin system comprises three endogenous 21-amino-acid peptide ligands endothelin-1, -2, and -3 (ET-1/2/3), and two G protein-coupled receptor (GPCR) subtypes-endothelin receptor A (ETAR) and B (ETBR). Since ET-1, the first endothelin, was identified in 1988 as one of the most potent endothelial cell-derived vasoconstrictor peptides with long-lasting actions, the endothelin system has attracted extensive attention due to its critical role in vasoregulation and close relevance in cardiovascular-related diseases. Here we present three cryo-electron microscopy structures of ETAR and ETBR bound to ET-1 and ETBR bound to the selective peptide IRL1620. These structures reveal a highly conserved recognition mode of ET-1 and characterize the ligand selectivity by ETRs. They also present several conformation features of the active ETRs, thus revealing a specific activation mechanism. Together, these findings deepen our understanding of endothelin system regulation and offer an opportunity to design selective drugs targeting specific ETR subtypes.


Assuntos
Doenças Cardiovasculares , Endotelina-1 , Humanos , Microscopia Crioeletrônica , Receptor de Endotelina A , Aminoácidos , Peptídeos
18.
Front Plant Sci ; 14: 1094157, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36844096

RESUMO

Phosphorus (P) is one of the essential macronutrients for plant growth and development, and it is an integral part of the major organic components, including nucleic acids, proteins and phospholipids. Although total P is abundant in most soils, a large amount of P is not easily absorbed by plants. Inorganic phosphate (Pi) is the plant-available P, which is generally immobile and of low availability in soils. Hence, Pi starvation is a major constraint limiting plant growth and productivity. Enhancing plant P efficiency can be achieved by improving P acquisition efficiency (PAE) through modification of morpho-physiological and biochemical alteration in root traits that enable greater acquisition of external Pi from soils. Major advances have been made to dissect the mechanisms underlying plant adaptation to P deficiency, especially for legumes, which are considered important dietary sources for humans and livestock. This review aims to describe how legume root growth responds to Pi starvation, such as changes in the growth of primary root, lateral roots, root hairs and cluster roots. In particular, it summarizes the various strategies of legumes to confront P deficiency by regulating root traits that contribute towards improving PAE. Within these complex responses, a large number of Pi starvation-induced (PSI) genes and regulators involved in the developmental and biochemical alteration of root traits are highlighted. The involvement of key functional genes and regulators in remodeling root traits provides new opportunities for developing legume varieties with maximum PAE needed for regenerative agriculture.

19.
Bioresour Technol ; 374: 128761, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36813048

RESUMO

Ascorbic acid was introduced to enhance the performance of zero-valent iron (Fe(0)) in hydrogen production by photo fermentation of bean dregs and corn stover. The highest hydrogen production of 664.0 ± 5.3 mL and hydrogen production rate of 34.6 ± 0.1 mL/h was achieved at 150 mg/L ascorbic acid, which was 10.1% and 11.5% higher than that of 400 mg/L Fe(0) alone. The supplement of ascorbic acid to Fe(0) system accelerated the formation of Fe(Ⅱ) in solution due to its reducing and chelating ability. Hydrogen production of Fe(0) and ascorbic acid-Fe(0) (AA-Fe(0)) systems at different initial pH (5, 6, 7, 8 and 9) was studied. Result showed that hydrogen produced from AA-Fe(0) system was improved by 2.7-27.5% compared with Fe(0) system. The maximum hydrogen production of 767.5 ± 2.8 mL was achieved with initial pH 9 in the AA-Fe(0) system. This study provided a strategy for enhancing biohydrogen production.


Assuntos
Hidrogênio , Zea mays , Fermentação , Ferro , Concentração de Íons de Hidrogênio
20.
Plant Physiol Biochem ; 194: 731-741, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36577197

RESUMO

Phosphorus (P) is one of the principal macronutrients for plant growth and productivity. Although the phosphate (Pi) transporter (PT) of the PHT1 family has been functionally characterized as participating in Pi uptake and transport in plants, information about PT genes in stylo (Stylosanthes guianensis), an important tropical forage legume that exhibits good adaptability to low-P acid soils, is limited. In this study, stylo root growth was found to be stimulated under P deficiency. The responses of PT genes to nutrient deficiencies and their roles in Pi uptake were further investigated in stylo. Four novel PT genes were identified in stylo and designated SgPT2 to SgPT5. Like SgPT1, which had been previously identified, all five SgPT proteins harboured the major facilitator superfamily (MFS) domain. Variations in tissue-specific expression were observed among the SgPT genes, which displayed diverse responses to deficiencies in nitrogen (N), P and potassium (K) in stylo roots. Four of the five SgPTs exhibited high levels of transcriptional responsiveness to P deficiency in roots. Furthermore, SgPT1, a Pi-starvation-induced gene closely related to legume PT homologues that participate in Pi transport, was selected for functional analysis. SgPT1 was localized to the plasma membrane. Analysis of transgenic Arabidopsis showed that overexpression of SgPT1 led to increased Pi accumulation and promoted root growth in Arabidopsis plants. Taken together, the results of this study suggest the involvement of SgPTs in the stylo response to nutrient deprivation. SgPT1 might mediate Pi uptake in stylo, which is beneficial for root growth during P deficiency.


Assuntos
Arabidopsis , Fabaceae , Fosfatos/metabolismo , Proteínas de Transporte de Fosfato/genética , Proteínas de Transporte de Fosfato/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Alanina Transaminase/genética , Alanina Transaminase/metabolismo , Fabaceae/genética , Fabaceae/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas
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