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1.
Microbiol Spectr ; 9(2): e0076721, 2021 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-34704793

RESUMO

Salinity is an important abiotic stress affecting plant growth. We have known that plants can recruit beneficial microbes from the surrounding soil. However, the ecological functions of the core microbiome in salt-tolerant plants, together with their driving factors, remain largely unexplored. Here, we employed both amplicon and shotgun metagenomic sequencing to investigate the microbiome and function signatures of bulk soil and rhizocompartment samples from three salt-tolerant plants (legumes Glycine soja and Sesbania cannabina and nonlegume Sorghum bicolor). Strong filtration effects for microbes and functional genes were found in the rhizocompartments following a spatial gradient. The dominant bacteria belonged to Ensifer for legumes and Bacillus for S. bicolor. Although different salt-tolerant plants harbored distinct bacterial communities, they all enriched genes involved in cell motility, Na+ transport, and plant growth-promoting function (e.g., nitrogen fixation and phosphate solubilization) in rhizoplane soils, implying that the microbiome assembly of salt-tolerant plants might depend on the ecological functions of microbes rather than microbial taxa. Moreover, three metagenome-assembled genomes affiliated to Ensifer were obtained, and their genetic basis for salt stress alleviation were predicted. Soil pH, electrical conductivity, and total nitrogen were the most important driving factors for explaining the above microbial and functional gene selection. Correspondingly, the growth of an endophyte, Ensifer meliloti CL09, was enhanced by providing root exudates, suggesting that root exudates might be one of factors in the selection of rhizosphere and endosphere microbiota. Overall, this study reveals the ecological functions of the populations inhabiting the root of salt-tolerant plants. IMPORTANCE Salinity is an important but little-studied abiotic stressor affecting plant growth. Although several previous reports have examined salt-tolerant plant microbial communities, we still lack a comprehensive understanding about the functional characteristics and genomic information of this population. The results of this study revealed the root-enriched and -depleted bacterial groups, and found three salt-tolerant plants harbored different bacterial populations. The prediction of three metagenome-assembled genomes confirmed the critical role of root dominant species in helping plants tolerate salt stress. Further analysis indicated that plants enriched microbiome from soil according to their ecological functions but not microbial taxa. This highlights the importance of microbial function in enhancing plant adaptability to saline soil and implies that we should pay more attention to microbial function and not only to taxonomic information. Ultimately, these results provide insight for future agriculture using the various functions of microorganisms on the saline soil.

2.
Plant Physiol Biochem ; 167: 816-830, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34530326

RESUMO

Apocynum venetum is a traditional Chinese medicinal herb with tolerance to various abiotic stresses, especially, salinity. However, only a few studies have investigated the salt-tolerant mechanism of this non-halophyte under salt stress at phenotypic and physiological levels. To explore the molecular mechanism of salinity tolerance in A. venetum, the global transcriptome profiles of seedling leaves under different salt-stress durations, using 200 mM NaCl, were analyzed. De novo assembly of approximately 715 million high-quality reads and approximately 105.61 Gb sequence data was performed. In total, 2822 differentially expressed genes (DEGs) were identified. DEGs were significantly enriched in flavonoid metabolism-related pathways such as "flavonoid biosynthesis" and "phenylpropanoid biosynthesis". Most of these DEGs were downregulated under salt stress. However, genes encoding the non-selective cation channels and antioxidants were upregulated under salt stress, whereas most cell wall-related DEGs were downregulated. Consequently, the concentration of flavonoids decreased, whereas that of Na+ increased with exposure time. Thus, we hypothesized that the accumulation of Na+ in the leaves, which resulted in reduced flavonoid concentration under salt stress, directly led to a decrease in the salt tolerance of A. venetum. This was verified by overexpressing four flavonoid synthesis pathway genes in Arabidopsis. The transgenic plants showed higher salt tolerance than the wild-type plants due to the accumulation of total flavonoids. These physiological and transcriptome analyses of A. venetum revealed major molecular underpinnings contributing to the responses of A. venetum to salt stress, thereby improving our understanding of the molecular mechanisms underlying salt tolerance in A. venetum and plants in general. The findings serve as a basis for functional studies on and engineering strategies for plant salinity tolerance.


Assuntos
Apocynum , Tolerância ao Sal , Apocynum/genética , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Estresse Salino , Tolerância ao Sal/genética , Transcriptoma
3.
Microb Biotechnol ; 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34570959

RESUMO

Bacterial wilt, caused by the Ralstonia solanacearum, can infect several economically important crops. However, the management strategies available to control this disease are limited. Plant growth-promoting rhizobacteria (PGPR) have been considered promising biocontrol agents. In this study, Bacillus amyloliquefaciens strain Cas02 was isolated from the rhizosphere soil of healthy tobacco plants and evaluated for its effect on plant growth promotion and bacterial wilt suppression. Strain Cas02 exhibited several growth-promoting-related features including siderophore production, cellulase activity, protease activity, ammonia production and catalase activity. Moreover, strain Cas02 showed a significant inhibitory growth effect on R. solanacearum, and its active substances were separated and identified to be macrolactin A and macrolactin W by HPLC-DAD-ESI-MS/MS. Both greenhouse and field experiments demonstrated a good performance of Cas02 in plant growth promotion and bacterial wilt suppression. To explore the underlying genetic mechanisms, complete genome sequencing was performed and the gene clusters responsible for antibacterial metabolites expression were identified. Overall, these findings suggest that the strain Cas02 could be a potential biocontrol agent in bacterial wilt management and a source of antimicrobial compounds for further exploitation.

4.
Plants (Basel) ; 10(8)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34451665

RESUMO

Phytophthora nicotianae is a widely distributed plant pathogen that can cause serious disease and cause significant economic losses to various crops, including tomatoes, tobacco, onions, and strawberries. To understand its pathogenic mechanisms and explore strategies for controlling diseases caused by this pathogen, we sequenced and analyzed the whole genome of Ph. nicotianae JM01. The Ph. nicotianae JM01 genome was assembled using a combination of approaches including shotgun sequencing, single-molecule sequencing, and the Hi-C technique. The assembled Ph. nicotianae JM01 genome is about 95.32 Mb, with contig and scaffold N50 54.23 kb and 113.15 kb, respectively. The average GC content of the whole-genome is about 49.02%, encoding 23,275 genes. In addition, we identified 19.15% of interspersed elements and 0.95% of tandem elements in the whole genome. A genome-wide phylogenetic tree indicated that Phytophthora diverged from Pythium approximately 156.32 Ma. Meanwhile, we found that 252 and 285 gene families showed expansion and contraction in Phytophthora when compared to gene families in Pythium. To determine the pathogenic mechanisms Ph. nicotianae JM01, we analyzed a suite of proteins involved in plant-pathogen interactions. The results revealed that gene duplication contributed to the expansion of Cell Wall Degrading Enzymes (CWDEs) such as glycoside hydrolases, and effectors such as Arg-Xaa-Leu-Arg (RXLR) effectors. In addition, transient expression was performed on Nicotiana benthamiana by infiltrating with Agrobacterium tumefaciens cells containing a cysteine-rich (SCR) protein. The results indicated that SCR can cause symptoms of hypersensitive response. Moreover, we also conducted comparative genome analysis among four Ph. nicotianae genomes. The completion of the Ph. nicotianae JM01 genome can not only help us understand its genomic characteristics, but also help us discover genes involved in infection and then help us understand its pathogenic mechanisms.

5.
Sci Total Environ ; 798: 149167, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34375261

RESUMO

Single biomass feedstock approach may not meet the requirements for developing biochar with desired characteristics for use as soil amendment. In this study, biochars were prepared by co-pyrolysis of nutrients-rich Enteromorpha prolifera and lignocellulose-rich corn straw (CPECs) at different mass ratios (3:7, 1:1, and 7:3). CPECs presented higher water-soluble N/P contents than corn straw biochar, and exhibited larger surface area, low Na content, and slower nutrient release rate than Enteromorpha prolifera biochar. The modification in physicochemical and properties of CPECs enhanced its potential application as a soil amendment. A pot experiment showed that CPECs derived from co-pyrolysis of appropriate ratios of Enteromorpha prolifera and corn straw (1:1, 7:3) significantly increased the biomass of cherry tomato plant by 64.05%, 40.03% and 81.88%, 55.25%, when compared with corn straw biochar and Enteromorpha prolifera biochar, respectively. The positive effects of CPECs were primarily attributed to improved soil properties (e.g., water holding capacity, soil organic matter, pH, soil nutrients content) and increased total N/P uptake by plants. The results of this work provided potentials of developing "designer" biochars to meet the multiple soil requirements by co-pyrolysis.


Assuntos
Solo , Zea mays , Carvão Vegetal , Pirólise
6.
BMC Cancer ; 21(1): 923, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34399705

RESUMO

BACKGROUND: Gastric cancer (GC) is one of the leading causes of cancer-related deaths worldwide. Human epidermal growth factor receptor 2 (HER2) amplification occurs in approximately 13-23% of all GC cases and patients with HER2 overexpression exhibit a poor prognosis. Lapatinib, a dual EGFR/HER2 tyrosine kinase inhibitor, is an effective agent to treat HER2-amplified breast cancer but it failed in gastric cancer (GC) clinical trials. However, the molecular mechanism of lapatinib resistance in HER2-amplified GC is not well studied. METHODS: We employed an unbiased, genome-scale screening with pooled CRISPR library on HER2-amplified GC cell lines to identify genes that are associated with resistance to lapatinib. To validate the candidate genes, we applied in vitro and in vivo pharmacological tests to confirm the function of the target genes. RESULTS: We found that loss of function of CSK or PTEN conferred lapatinib resistance in HER2-amplified GC cell lines NCI-N87 and OE19, respectively. Moreover, PI3K and MAPK signaling was significantly increased in CSK or PTEN null cells. Furthermore, in vitro and in vivo pharmacological study has shown that lapatinib resistance by the loss of function of CSK or PTEN, could be overcome by lapatinib combined with the PI3K inhibitor copanlisib and MEK inhibitor trametinib. CONCLUSIONS: Our study suggests that loss-of-function mutations of CSK and PTEN cause lapatinib resistance by re-activating MAPK and PI3K pathways, and further proved these two pathways are druggable targets. Inhibiting the two pathways synergistically are effective to overcome lapatinib resistance in HER2-amplified GC. This study provides insights for understanding the resistant mechanism of HER2 targeted therapy and novel strategies that may ultimately overcome resistance or limited efficacy of lapatinib treatment for subset of HER2 amplified GC.


Assuntos
Biomarcadores Tumorais/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Receptor ErbB-2/metabolismo , Neoplasias Gástricas/tratamento farmacológico , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Apoptose , Biomarcadores Tumorais/genética , Proliferação de Células , Feminino , Perfilação da Expressão Gênica , Humanos , Lapatinib/administração & dosagem , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Piridonas/administração & dosagem , Pirimidinas/administração & dosagem , Pirimidinonas/administração & dosagem , Quinazolinas/administração & dosagem , Receptor ErbB-2/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Bioresour Technol ; 340: 125668, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34339999

RESUMO

This study evaluated the effects of biocontrol Bacillus and fermenting bacteria addition on the microbial community, metabolic functions and antibiotic resistance genes (ARGs) of new prickly ash seed oil meal (PSOM)-biochar composting. The results showed that the addition of Bacillus subtilis and fermentation bacteria significantly increased the NH4+-N, bacterial abundance and fungal diversity of compost while decreasing the relative abundances (RAs) of carbon metabolism genes in mature compost. NH4+-N was significantly correlated with microbial abundance and diversity, and its increase was closely related to microbial amino acid metabolism. The addition of biocontrol and fermenting bacteria changed the RAs of ARGs, which was caused by changes in the potential hosts Proteobacteria, Bacteroidota and Firmicutes in the compost. Consequently, adding Bacillus and fermenting bacteria into PSOM to make composting was suggested as an effective method to promote nutrient transformation, regulate microbial activity and decrease RAs of tetracycline and vancomycin ARGs.


Assuntos
Bacillus , Compostagem , Microbiota , Antibacterianos/farmacologia , Bacillus/genética , Bacillus subtilis , Carvão Vegetal , Resistência Microbiana a Medicamentos , Fermentação , Genes Bacterianos , Esterco , Óleos Vegetais
8.
Artigo em Inglês | MEDLINE | ID: mdl-34224879

RESUMO

Complex structural variants (CSVs) are genomic alterations that have more than two breakpoints and are considered as the simultaneous occurrence of simple structural variants. However, detecting the compounded mutational signals of CSVs is challenging through a commonly used model-match strategy. As a result, there has been limited progress for CSV discovery compared with simple structural variants. We systematically analyzed the multi-breakpoint connection feature of CSVs, and proposed Mako, utilizing a bottom-up guided model-free strategy, to detect CSVs from paired-end short-read sequencing. Specifically, we implemented a graph-based pattern growth approach, where the graph depicts potential breakpoint connections, and pattern growth enables CSV detection without pre-defined models. Comprehensive evaluations on both simulated and real datasets revealed that Mako outperformed other algorithms. Notably, validation rates of CSV on real data based on experimental and computational validations as well as manual inspections are around 70%, where the medians of experimental and computational breakpoint shift are 13bp and 26bp, respectively. Moreover, the Mako CSV subgraph effectively characterized the breakpoint connections of a CSV event and uncovered a total of 15 CSV types, including two novel types of adjacent segments swap and tandem dispersed duplication. Further analysis of these CSVs also revealed the impact of sequence homology in the formation of CSVs. Mako is publicly available at https://github.com/xjtu-omics/Mako.

9.
J Hazard Mater ; 417: 126047, 2021 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-33992003

RESUMO

A 35-day microcosmic experiment was conducted with lettuce (Lactuca sativa L.) and two metalaxyl (MET) enantiomers (R-MET and S-MET) to understand the roles of biochar in the enantioselective fate of chiral pesticides in soil-plant ecosystems. Wood waste-derived biochar (WBC) amendment effectively decreased the shoot concentrations of R-MET/S-MET and their metabolites R-MET/S-MET acid by 57.7-86.3% and 13.3-32.5%, respectively. The reduced uptake was mainly attributed to the decreased bioavailability of R-MET and S-MET. A lower fraction of R-MET was accumulated by the lettuce in the WBC-amended soils relative to the control, suggesting a decrease in the enantioselective uptake of the chiral pesticide MET in the presence of biochar. Regardless of the WBC amendment, no enantiomerization of MET or MET acid occurred. The application of WBC stimulated soil bacterial diversity, shifted the bacterial community, and enhanced the abundance of pesticide degrading bacteria (e.g., Luteimonas, Methylophilus, and Hydrogenophaga), which were responsible for the enantioselective degradation of MET in the soil. This work expands our understanding of the enantioselective fate of chiral pesticides in the biochar-amended soil ecosystems. These findings can be used to develop biochar-based technologies to remediate soils contaminated with these chiral pesticides to ensure food safety.


Assuntos
Praguicidas , Poluentes do Solo , Alanina/análogos & derivados , Bactérias , Carvão Vegetal , Ecossistema , Alface , Solo , Poluentes do Solo/análise , Estereoisomerismo
10.
Front Plant Sci ; 12: 655673, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33959142

RESUMO

Recent studies have observed differing microbiomes between disease-suppressive and disease-conducive soils. However, it remains unclear whether the microbial keystone taxa in suppressive soil are critical for the suppression of diseases. Bacterial wilt is a common soil-borne disease caused by Ralstonia solanacearum that affects tobacco plants. In this study, two contrasting tobacco fields with bacterial wilt disease incidences of 0% (disease suppressive) and 100% (disease conducive) were observed. Through amplicon sequencing, as expected, a high abundance of Ralstonia was found in the disease-conducive soil, while large amounts of potential beneficial bacteria were found in the disease-suppressive soil. In the fungal community, an abundance of the Fusarium genus, which contains species that cause Fusarium wilt, showed a positive correlation (p < 0.001) with the abundance of Ralstonia. Network analysis revealed that the healthy plants had more complex bacterial networks than the diseased plants. A total of 9 and 13 bacterial keystone taxa were identified from the disease-suppressive soil and healthy root, respectively. Accumulated abundance of these bacterial keystones showed a negative correlation (p < 0.001) with the abundance of Ralstonia. To complement network analysis, culturable strains were isolated, and three species belonging to Pseudomonas showed high 16S rRNA gene similarity (98.4-100%) with keystone taxa. These strains displayed strong inhibition on pathogens and reduced the incidence of bacterial wilt disease in greenhouse condition. This study highlighted the importance of keystone species in the protection of crops against pathogen infection and proposed an approach to obtain beneficial bacteria through identifying keystone species, avoiding large-scale bacterial isolation and cultivation.

11.
Plants (Basel) ; 10(4)2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-33924154

RESUMO

Wild soybean (Glycine soja Sieb.et Zucc; WS) has been used as a traditional food in China for many years and contains significantly higher levels of isoflavones than cultivated soybean (Glycine max; CS), but the secondary metabolites, including flavonoids and the phenolic composition differences between them, remain unclear. The results showed that WS possessed significantly higher total phenolic and flavonoid content and exhibited better antioxidant and α-glucosidase inhibition activities as well as excellent protective effects against H2O2-induced oxidative injury in a human endothelial cell line. Through metabolomic analysis, 642 metabolites were identified, and 238 showed differential expression, with 151 upregulated and 87 downregulated. A total of 79 flavonoid compounds were identified, 42 of which were upregulated in WS. 2'-Hydroxygenistein, garbanzol, protocatechuic aldehyde, ligustilide, and resveratrol were the most discriminated compounds in WS. The metabolic pathway analysis of differential metabolites related to the biosynthesis of flavonoids and phenolic acids were the biosynthesis of phenylpropanoids, flavonoids, isoflavonoids, flavones, and flavonols. This study substantially elucidated differences in the content of flavonoids and biological activities between WS and CS, which is useful information for the effective utilization of these two black soybean species in food processing.

13.
Int J Biol Macromol ; 180: 547-558, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33741372

RESUMO

A fuciodan (Mw = 11.1 kDa) was obtained and purified from Macrocystis pyrifera (MPF). MPF was an acid heteropolysaccharide including fucose, mannose, xylose, galactose, rhamnose, glucuronic acid, and glucose in a molar ratio of 3.1:1.0:0.86:0.63:0.25:0.33:0.11. Sulfate content in MPF was 28.6%, and the molar ratio of fucose to sulfate (Fuc:SO42-) was 1.0:0.58. The structure of MPF was mainly consist of repeating →3)-ß-L-Fucp (2SO3-)-(1→ and →4)-ß-D-Xylp-(1→3)-ß-L-Fucp(2SO3-)-(1→ and with α-L-Fucp-(1→ and →6)-α-D-Galp-(1→ in branches. Moreover, the effects of different MPF concentrations on plant salt tolerance were investigated. The results indicated that MPF could improve the salt tolerance of wheat seedlings. Among the five concentrations (0.05, 0.1, 0.5, 1, and 2 mg/ml), 0.5 and 1 mg/ml MPF were optimal for effective plant salt-resistance activity. These results suggested that MPF extracted from brown seaweed show potential as plant stimulators that may be used to improve salt resistance of plants.


Assuntos
Macrocystis/química , Polissacarídeos/química , Estresse Salino/fisiologia , Tolerância ao Sal/fisiologia , Plântula/fisiologia , Triticum/fisiologia , Antioxidantes/metabolismo , Relação Dose-Resposta a Droga , Fucose/análise , Peróxido de Hidrogênio/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Microscopia Eletrônica de Varredura , Polissacarídeos/isolamento & purificação , Polissacarídeos/farmacologia , Estresse Salino/efeitos dos fármacos , Tolerância ao Sal/efeitos dos fármacos , Plântula/efeitos dos fármacos , Plântula/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier , Sulfatos/análise , Superóxido Dismutase/metabolismo , Triticum/efeitos dos fármacos , Triticum/metabolismo
14.
Plant Physiol Biochem ; 162: 667-676, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33780740

RESUMO

Soil salinity is a major limiting factor for agricultural production, threatening food security worldwide. A thorough understanding of the mechanisms underlying plant responses is required to effectively counter its deleterious effects on crop productivity. Total flavonoid accumulation reportedly improves salinity tolerance in many crops. Therefore, we isolated the full-length cDNA of a flavonol synthetase (FLS) gene from Apocynum venetum (AvFLS). The gene contained a 1008-bp open reading frame encoding a protein composed of 335 amino acid residues. Multiple sequence alignment showed that the AvFLS protein was highly homologous to FLSs from other plants. AvFLS was expressed in leaves, stems, roots, flowers, and germinated seeds. Expression pattern analysis revealed that AvFLS was significantly induced by salinity stress. AvFLS overexpression in tobacco positively affected the development and growth of transgenic plants under salinity stress: root and seedling growth were inhibited to a lesser extent, while seed germination rate increased. Additionally, the overexpression of AvFLS under salinity stress resulted in an increase in total flavonoid content (1.63 mg g-1 in wild-type samples and 4.63 mg g-1 on average in transgenic samples), which accompanied the increase in the activity of antioxidant enzymes and inhibited the production of reactive oxygen species. Further, AvFLS-overexpressing transgenic tobacco plants absorbed more K+ than wild type plants, leading to an increased K+/Na+ ratio, which in turn contributed to the maintenance of Na+/K+ homeostasis. These findings suggest that an AvFLS-induced increase in total flavonoid content enhanced plant salinity tolerance, implying the importance of AvFLS gene responses to salinity stress.


Assuntos
Apocynum , Tolerância ao Sal , Apocynum/metabolismo , Flavonóis , Regulação da Expressão Gênica de Plantas , Ligases , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Salinidade , Estresse Salino , Tolerância ao Sal/genética , Estresse Fisiológico/genética , Tabaco/genética , Tabaco/metabolismo
15.
Sci Total Environ ; 775: 144893, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-33618299

RESUMO

Coastal soil is an important land reserve that may be used to alleviate the shortage of cultivated land; however, this soil is stressed by saline conditions and nutrient deficiency. Biochar offers the potential to reclaim coastal soil, but the response of plant growth to biochar addition in salt-affected soil is species-dependent. In this study, the response of ice plant (Mesembryanthemum crystallinum L.), an economically valuable halophyte that grows in the coastal soil of the Yellow River Delta, to wood chip biochar (WBC) either alone or in combination with chemical fertilizer was investigated using a 90-day pot experiment. The WBC enhanced the growth of ice plants in the coastal soil, but combining it with chemical fertilizer did not increase its effect. The nutritional quality of the plants was improved by the addition of WBC, regardless of whether chemical fertilizer was applied; moreover, WBC amendment enhanced photosynthesis and reduced the oxidative stress of the plants. The ameliorated soil properties (e.g., soil organic matter and water holding capacity) and increased contents of available macronutrients (e.g., P and K) and micronutrients (e.g., Mg, Mn, B and Zn) resulting from soil amendment with WBC may have contributed to the enhanced growth and quality of the ice plants. Additionally, in soil modified with WBC, an increased abundance of beneficial taxa (e.g., Erythrobacter, Sphingomonas and Lysobacter) and a shift in the microbial community may also have helped to improve the growth and quality of the ice plants. The results of our study provide useful information for developing a biochar-based technology to use in combination with valuable halophytes to reclaim degraded coastal soil and enhance food security.


Assuntos
Mesembryanthemum , Solo , Carvão Vegetal , China , Fertilizantes , Rios
16.
Cell Mol Immunol ; 18(3): 735-745, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33514849

RESUMO

Graves' orbitopathy (GO), the most severe manifestation of Graves' hyperthyroidism (GH), is an autoimmune-mediated inflammatory disorder, and treatments often exhibit a low efficacy. CD4+ T cells have been reported to play vital roles in GO progression. To explore the pathogenic CD4+ T cell types that drive GO progression, we applied single-cell RNA sequencing (scRNA-Seq), T cell receptor sequencing (TCR-Seq), flow cytometry, immunofluorescence and mixed lymphocyte reaction (MLR) assays to evaluate CD4+ T cells from GO and GH patients. scRNA-Seq revealed the novel GO-specific cell type CD4+ cytotoxic T lymphocytes (CTLs), which are characterized by chemotactic and inflammatory features. The clonal expansion of this CD4+ CTL population, as demonstrated by TCR-Seq, along with their strong cytotoxic response to autoantigens, localization in orbital sites, and potential relationship with disease relapse provide strong evidence for the pathogenic roles of GZMB and IFN-γ-secreting CD4+ CTLs in GO. Therefore, cytotoxic pathways may become potential therapeutic targets for GO.

17.
Waste Manag ; 120: 576-584, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33129652

RESUMO

With the development of marine biorefinery concept, utilisation of algal waste during industrial processing as well as some "green tide" waste biomass has become an important research topic. In this work, a single-step microwave process was used to hydrolyse Laminaria japonica processing waste (LJW) and Enteromorpha prolifera (EP), producing a growth medium suitable for microbial cultivation. The medium contained a range of mono- and polysaccharides as well as macro- and micronutrients that could be used by the microbes. The cultivation behavior of three plant growth-promoting rhizobacteria (PGPR) strains (Bacillus subtilis strain Tpb55, Bacillus amyloliquefaciens strain Cas02, and Burkholderia pyrrocinia strain Lyc2) in the two media were investigated. LJW hydrolysate from 180 °C and EP hydrolysate from 150 °C performed better cultivation efficiency than those hydrolysates from other microwave conditions. Saccharide analysis showed that microbes metabolized some monosaccharide such as glucose, mannose during cultivation, leaving polysaccharide unused in the medium. Furthermore, hydrolysate-strain cultivation mixtures were applied to pepper growth. The EP hydrolysate-Cas02 broth showed better plant growth-promoting effect compared to other treatments, which might be attributed to the higher indole-3-acetic acid (IAA) production of Cas02 in the EP hydrolysate. This work shed lights on the conversion of algal waste to PGPR biomass as well as the co-application of algal hydrolysates- strains cultivation broth for a better plant growth promotion.


Assuntos
Bacillus subtilis , Biomassa , Burkholderia
18.
J Agric Food Chem ; 68(50): 14781-14789, 2020 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-33274637

RESUMO

With the perpetuation of soil salinization, it is imperative to improve the salt and alkaline tolerance of crops. Sorghum bicolor, a C4 crop, is often grown in semiarid areas due to its high tolerance of various abiotic stresses. Whether to improve the resistance of the sorghum itself or that of other crops, it is necessary to understand the response of sorghum under saline-alkali stress. An integrative analysis of the metabolome and transcriptome of sorghum under normal conditions and treatments of moderate and severe saline-alkali stress was performed. Among the different accumulated metabolites (DAMs) and differentially expressed genes (DEGs), flavonoid-related DAMs and DEGs were clearly changed. The level of flavonoids was increased under saline-alkali stress, and the change in flavonoids was dynamic as to whether total flavonoids or most flavonoid components accumulated more under moderate saline-alkali stress compared to severe stress. Some flavonoid metabolites were significantly correlated with the expression of flavonoid biosynthesis genes. MYB transcription factors may also contribute to the regulation of flavonoids levels. These findings present the dynamic changes and possible molecular mechanisms of flavonoids under different saline-alkali stresses and provide a foundation for future research and crop improvement.


Assuntos
Álcalis/metabolismo , Flavonoides/biossíntese , Proteínas de Plantas/genética , Cloreto de Sódio/metabolismo , Sorghum/fisiologia , Regulação da Expressão Gênica de Plantas , Folhas de Planta/genética , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Sorghum/genética , Estresse Fisiológico , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcriptoma
19.
Plants (Basel) ; 9(12)2020 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-33256075

RESUMO

The composition and allelopathy to Phytophthora nicotianae (the causal agent of tobacco black shank disease) of root exudates from a resistant tobacco (Nicotiana tabacum L.) cultivar Gexin 3, a susceptible cultivar Xiaohuangjin 1025 and their reciprocal grafts were investigated. Grafting with disease-resistant rootstock could improve resistance to black shank; this is closely related to the allelopathy of root exudates. The root exudates from the resistant cultivar inhibited the growth of P. nicotianae, while those from the susceptible cultivar promoted the growth; the grafting varieties had intermediate properties. The root exudate composition differed among cultivars. Gexin 3 was rich in esters and fatty acids, while Xiaohuangjin 1025 contained more hydrocarbons and phenolic acids. The composition of root exudates of grafted cultivars as well as their allelopathy to P. nicotianae were altered, and tended to be close to the composition of cultivar used as rootstock. Eugenol, 4-tert-butylphenol, mono (2-ethylhexyl) phthalate, 4-hydroxybenzoic acid, 2,6-di-tert-butylphenol, dipropyl phthalate, and methyl myristate were identified as the main compounds contributing to inhibitory properties of root exudates. Sorbitol was suggested to play a role in disease induction. Overall, rootstock-scion interaction affected the composition of tobacco root exudates, which may be attributed to the different disease resistance among grafted plants, rootstock and scion.

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