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1.
Front Microbiol ; 14: 1215024, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38075888

RESUMO

Camellia oleifera Abel, a woody oil plant, that is endemic to China. Tea oil, also referred to as "oriental olive oil," is a superior quality plant-based cooking oil. The production of tea oil accounts for 8% of the total edible vegetable oil production in the country. Since 2022, the annual output value of C. oleifera industry has exceeded 100 billion yuan, making it one of the major economic contributors to China's rural revitalization development strategy. In recent years, demand and production have grown in parallel. However, this has led to an increase in the incidence levels of pest and diseases. Pests and diseases significantly reduce the quality and yield of C. oleifera. C. oleifera diseases are mainly caused by pathogenic fungi. C. oleifera anthracnose, soft rot, leaf spot, coal stain, leaf gall disease, and root rot are the most important fungal diseases affecting the C. oleifera industry. However, the same disease may be caused by different pathogenic fungi. C. oleifera can be found in half of China and is found in several climatic zones. The geographical distribution of woody plant diseases is consistent with the distribution of the tree species and the ecology of the range, which also results in a highly complex distribution of fungal diseases of C. oleifera. The management of fungal diseases in C. oleifera is extremely challenging due to the variety of pathogenic fungal species, multiple routes of transmission, the lack of resistant plants, and the environmental safety of chemical measures. The optimal strategy for addressing fungal diseases in C. oleifera is to develop and apply an integrated disease management plan. This review provides a brief overview of the pathogenic species, pathogenesis, pathogenesis, geographical distribution, current management strategies, and potentially new methods of C. oleifera fungal diseases, to provide direction for the development of comprehensive management measures for C. oleifera fungal diseases in the future.

2.
Front Microbiol ; 14: 1252039, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37876778

RESUMO

Phytopathogens pose a devastating threat to the productivity and yield of crops by causing destructive plant diseases in natural and agricultural environments. Hemibiotrophic pathogens have a variable-length biotrophic phase before turning to necrosis and are among the most invasive plant pathogens. Plant resistance to hemibiotrophic pathogens relies mainly on the activation of innate immune responses. These responses are typically initiated after the plant plasma membrane and various plant immune receptors detect immunogenic signals associated with pathogen infection. Hemibiotrophic pathogens evade pathogen-triggered immunity by masking themselves in an arms race while also enhancing or manipulating other receptors to promote virulence. However, our understanding of plant immune defenses against hemibiotrophic pathogens is highly limited due to the intricate infection mechanisms. In this review, we summarize the strategies that different hemibiotrophic pathogens interact with host immune receptors to activate plant immunity. We also discuss the significant role of the plasma membrane in plant immune responses, as well as the current obstacles and potential future research directions in this field. This will enable a more comprehensive understanding of the pathogenicity of hemibiotrophic pathogens and how distinct plant immune receptors oppose them, delivering valuable data for the prevention and management of plant diseases.

3.
Nat Protoc ; 18(9): 2642-2670, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37626246

RESUMO

A lack of generic and effective genetic manipulation methods for Pseudomonas has restricted fundamental research and utilization of this genus for biotechnology applications. Phage-encoded homologous recombination (PEHR) is an efficient tool for bacterial genome engineering. This PEHR system is based on a lambda Red-like operon (BAS) from Pseudomonas aeruginosa phage Ab31 and a Rac bacteriophage RecET-like operon (Rec-TEPsy) from P. syringae pv. syringae B728a and also contains exogenous elements, including the RecBCD inhibitor (Redγ or Pluγ) or single-stranded DNA-binding protein (SSB), that were added to enhance the PEHR recombineering efficiency. To solve the problem of false positives in Pseudomonas editing with the PEHR system, the processive enzyme Cas3 with a minimal Type I-C Cascade-based system was combined with PEHR. This protocol describes the utilization of a Pseudomonas-specific PEHR-Cas3 system that was designed to universally and proficiently modify the genomes of Pseudomonas species. The pipeline uses standardized cassettes combined with the concerted use of SacB counterselection and Cre site-specific recombinase for markerless or seamless genome modification, in association with vectors that possess the selectively replicating template R6K to minimize recombineering background. Compared with the traditional allelic exchange editing method, the PEHR-Cas3 system does not need to construct suicide plasmids carrying long homologous arms, thus simplifying the experimental procedure and shortening the traceless editing period. Compared with general editing systems based on phage recombinases, the PEHR-Cas3 system can effectively improve the screening efficiency of mutants using the cutting ability of Cas3 protein. The entire procedure requires ~12 days.


Assuntos
Bacteriófagos , Proteínas Associadas a CRISPR , Humanos , Alelos , Recombinação Homóloga , Pseudomonas
4.
Sensors (Basel) ; 23(12)2023 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-37420845

RESUMO

In recent years, artificial intelligence (AI) technology has promoted the development of electroencephalogram (EEG) emotion recognition. However, existing methods often overlook the computational cost of EEG emotion recognition, and there is still room for improvement in the accuracy of EEG emotion recognition. In this study, we propose a novel EEG emotion recognition algorithm called FCAN-XGBoost, which is a fusion of two algorithms, FCAN and XGBoost. The FCAN module is a feature attention network (FANet) that we have proposed for the first time, which processes the differential entropy (DE) and power spectral density (PSD) features extracted from the four frequency bands of the EEG signal and performs feature fusion and deep feature extraction. Finally, the deep features are fed into the eXtreme Gradient Boosting (XGBoost) algorithm to classify the four emotions. We evaluated the proposed method on the DEAP and DREAMER datasets and achieved a four-category emotion recognition accuracy of 95.26% and 94.05%, respectively. Additionally, our proposed method reduces the computational cost of EEG emotion recognition by at least 75.45% for computation time and 67.51% for memory occupation. The performance of FCAN-XGBoost outperforms the state-of-the-art four-category model and reduces computational costs without losing classification performance compared with other models.


Assuntos
Inteligência Artificial , Emoções , Reconhecimento Psicológico , Algoritmos , Eletroencefalografia/métodos
5.
Microbiol Spectr ; 10(5): e0139622, 2022 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-36190425

RESUMO

Gut microbes can affect host adaptation to various environment conditions. Escherichia coli is a common gut species, including pathogenic strains and nonpathogenic strains. This study was conducted to investigate the effects of different E. coli strains in the gut on the health of pigs. In this study, the complete genomes of two E. coli strains isolated from pigs were sequenced. The whole genomes of Y18J and the enterotoxigenic E. coli strain W25K were compared to determine their roles in pig adaptation to disease. Y18J was isolated from feces of healthy piglets and showed strong antimicrobial activity against W25K in vitro. Gene knockout experiments and complementation analysis followed by modeling the microbe-microbe interactions demonstrated that the antagonistic mechanism of Y18J against W25K relied on the bacteriocins colicin B and colicin M. Compared to W25K, Y18J is devoid of exotoxin-coding genes and has more secondary-metabolite-biosynthetic gene clusters. W25K carries more genes involved in genome replication, in accordance with a shorter cell cycle observed during a growth experiment. The analysis of gut metagenomes in different pig breeds showed that colicins B and M were enriched in Laiwu pigs, a Chinese local breed, but were scarce in boars and Duroc pigs. IMPORTANCE This study revealed the heterogeneity of E. coli strains from pigs, including two strains studied by both in silico and wet experiments in detail and 14 strains studied by bioinformatics analysis. E. coli Y18J may improve the adaptability of pigs toward disease resistance through the production of colicins B and M. Our findings could shed light on the pathogenic and harmless roles of E. coli in modern animal husbandry, leading to a better understanding of intestinal-microbe-pathogen interactions in the course of evolution.


Assuntos
Anti-Infecciosos , Bacteriocinas , Colicinas , Escherichia coli Enterotoxigênica , Infecções por Escherichia coli , Animais , Suínos , Masculino , Colicinas/genética , Colicinas/metabolismo , Escherichia coli Enterotoxigênica/genética , Escherichia coli Enterotoxigênica/metabolismo , Infecções por Escherichia coli/veterinária , Diarreia/veterinária , Bacteriocinas/genética , Exotoxinas
6.
Front Microbiol ; 12: 753195, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34880838

RESUMO

Trace minerals are extremely important for balanced nutrition, growth, and development in animals and humans. Phytic acid chelation promotes the use of probiotics in nutrition. The phytic acid-degrading strain Lactococcus lactis psm16 was obtained from swine milk by enrichment culture and direct plate methods. In this study, we evaluated the effect of the strain psm16 on mineral element content in a mouse model. Mice were divided into four groups: basal diet, 1% phytic acid, 1% phytic acid + psm16, 1% phytic acid + 500 U/kg commercial phytase. Concentrations of acetic acid, propionic acid, butyric acid, and total short-chain fatty acids were significantly increased in the strain psm16 group compared to the phytic acid group. The concentrations of copper (p = 0.021) and zinc (p = 0.017) in liver, calcium (p = 0.000), manganese (p = 0.000), and zinc (p = 0.000) in plasma and manganese (p = 0.010) and zinc (p = 0.022) in kidney were significantly increased in psm16 group, while copper (p = 0.007) and magnesium (p = 0.001) were significantly reduced. In conclusion, the addition of phytic acid-degrading bacteria psm16 into a diet including phytic acid can affect the content of trace elements in the liver, kidney, and plasma of mice, counteracting the harmful effects of phytic acid.

7.
Biotechnol J ; 16(8): e2000575, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33484238

RESUMO

Microbial natural products among other functions they play a vital role in the disease prevention in humans, animals and plants. Pseudomonas parafulva CRS01-1 is a broad-spectrum antagonistic bacterium present in plants. However, no natural products have been isolated from this strain till date. Corresponding biosynthetic gene clusters to natural products is an effective method for bioprospecting, for which, genome manipulation tools are essential. We previously developed Pseudomonas-specific phage-derived homologous recombination systems for genetic engineering in four Pseudomonas species. Herein, we report the application of these recombineering systems in Pseudomonas parafulva CRS01-1, along with structural elucidation and bioactivity evaluation of natural products. The Pseudomonas recombineering toolbox established before in different four species is efficient for genome mining and bioactive metabolite discovery from more distant species.


Assuntos
Produtos Biológicos , Vias Biossintéticas , Vias Biossintéticas/genética , Engenharia Genética , Humanos , Família Multigênica , Pseudomonas/genética
8.
Front Microbiol ; 12: 761189, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35265047

RESUMO

Weaning of piglets could increase the risk of infecting with Gram-negative pathogens, which can further bring about a wide array of virulence factors including the endotoxin lipopolysaccharide (LPS). It is in common practice that the use of antibiotics has been restricted in animal husbandry. Alkaline phosphatase (AKP) plays an important role in the detoxification and anti-inflammatory effects of LPS. This study investigated the protective effects of AKP on intestinal epithelial cells during inflammation. Site-directed mutagenesis was performed to modulate the AKP activity. The enzyme activity tests showed that the activity of the DelSigD153G-D330N mutants in B. subtilis was nearly 1,600 times higher than that of the wild-type AKP. In this study, an in vitro LPS-induced inflammation model using IPEC-J2 cells was established. The mRNA expression of interleukin-(IL-) 6, IL-8, and tumor necrosis factor-α (TNF-α) were extremely significantly downregulated, and that of ASC amino acid transporter 2 (ASCT-2), zonula occludens protein-1 (ZO-1), and occludin-3 (CLDN-3) were significantly upregulated by the DelSigD153G-D330N mutant compared with LPS treatment. This concludes the anti-inflammatory role of AKP on epithelial membrane, and we are hopeful that this research could achieve a sustainable development for the pig industry.

9.
Front Microbiol ; 12: 762467, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34975787

RESUMO

Lactic acid bacteria (LAB) are vital probiotics in the food processing industry, which are widely spread in food additives and products, such as meat, milk, and vegetables. Pediococcus pentosaceus (P. pentosaceus), as a kind of LAB, has numerous probiotic effects, mainly including antioxidant, cholesterol-lowering, and immune effects. Recently, the applications in the probiotic- fermentation products have attracted progressively more attentions. However, it is necessary to screen P. pentosaceus with abundant functions from diverse sources due to the limitation about the source and species of P. pentosaceus. This review summarized the screening methods of P. pentosaceus and the exploration methods of probiotic functions in combination with the case study. The screening methods included primary screening and rescreening including gastric acidity resistance, bile resistance, adhesion, antibacterial effects, etc. The application and development prospects of P. pentosaceus were described in detail, and the shortcomings in the practical application of P. pentosaceus were evaluated to make better application of P. pentosaceus in the future.

10.
J Nanosci Nanotechnol ; 18(6): 4397-4402, 2018 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29442794

RESUMO

In this work, we demonstrate the feasibility of preparing Au/TiO2 nanorods via a dc magnetron sputtering at room temperature and heat-treatment at 500 °C in air for 2 h. The heat treatment leads to the migration of Au atoms into TiO2 nanofilm to form Au/TiO2 nanorods with Au nanoparticles embedded in the TiO2 nanorods of anatase phase. The Au nanoparticles in the TiO2 nanorods suppress the charge recombination. These Au/TiO2 nanorods showed high absorption and intensive response to the visible light and had improved photocatalytic properties in comparison with pure TiO2 nanoparticles formed by using similar method.

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