Publications by authors named "Maria A C Horta"

can cause invasive pulmonary aspergillosis (IPA). Fungicidal azoles and fungistatic caspofungin (CAS) are the first- and second-line therapies, respectively, used to treat IPA. Treatment of with CAS or micafungin induces the production of the oxylipin 5,8-diHODE by the fungal oxygenase PpoA.

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Article Synopsis
  • Aspergillus fumigatus causes the infection known as aspergillosis and uses asexual spores to infect hosts, but little is known about how it evades the immune system.
  • In this study, researchers analyzed the conidial surface proteins of A. fumigatus and compared them to two non-pathogenic species, discovering 62 proteins unique to A. fumigatus.
  • Testing null mutants for 42 genes revealed that deleting 33 of these genes affected the fungus's ability to resist immune responses, particularly highlighting a gene that influences the proinflammatory cytokine IL-1β, which is crucial for infection in a mouse model.
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  • The study investigates the role of conidial surface proteins in the pathogenic fungus responsible for aspergillosis and compares it with non-pathogenic species.
  • Researchers identified 62 proteins specifically expressed on the surface of the conidia and deleted genes for 42 of these proteins to assess their impact on infection.
  • Findings indicate that certain proteins, particularly one related to IL-1β production, are crucial for the fungus in evading the immune response during initial host infection.
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  • Aspergillus fumigatus is a fungus that can thrive in the environment and cause disease in humans, highlighting the need to study its genomic variations to understand its pathogenicity and drug resistance.
  • The study analyzed 206 isolates (133 from clinical settings and 73 from the environment) and found that while most genes are conserved across isolates, about 40.6% showed variability, but this variation was not linked to whether the isolate was clinical or environmental.
  • The findings indicate that despite noticeable physical differences between clinical and environmental isolates, genetically, they are quite similar, suggesting that the evolutionary mechanisms of A. fumigatus are more complex than previously thought.
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whose gene expression is tightly controlled by the transcription factors (TFs) XYR1 and CRE1, is a potential candidate for hydrolytic enzyme production. Here, we performed a network analysis of IOC-3844 and CBMAI-0179 to explore how the regulation of these TFs varies between these strains. In addition, we explored the evolutionary relationships of XYR1 and CRE1 protein sequences among spp.

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Aspergillus fumigatus causes a range of human and animal diseases collectively known as aspergillosis. A. fumigatus possesses and expresses a range of genetic determinants of virulence, which facilitate colonisation and disease progression, including the secretion of mycotoxins.

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Fungi are key players in biotechnological applications. Although several studies focusing on fungal diversity and genetics have been performed, many details of fungal biology remain unknown, including how cellulolytic enzymes are modulated within these organisms to allow changes in main plant cell wall compounds, cellulose and hemicellulose, and subsequent biomass conversion. With the advent and consolidation of DNA/RNA sequencing technology, different types of information can be generated at the genomic, structural and functional levels, including the gene expression profiles and regulatory mechanisms of these organisms, during degradation-induced conditions.

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Article Synopsis
  • Aspergillus fumigatus is a major fungal pathogen that causes aspergillosis, which can become severe in immunocompromised individuals.
  • The treatment options for aspergillosis are limited, mainly relying on azole drugs, but resistance to these drugs is increasing, highlighting the need for new antifungal strategies.
  • By screening over 1,100 compounds, researchers found miltefosine as a potential antifungal, with a transcription factor called SmiA identified as crucial for the fungus’s response to the drug, affecting sphingolipid regulation.
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Bioprospecting genes and proteins related to plant biomass degradation is an attractive approach for the identification of target genes for biotechnological purposes, especially those with potential applications in the biorefinery industry that can enhance second-generation ethanol production technology. Trichoderma harzianum is a potential candidate for cellulolytic enzyme prospection and production. Herein, the enzymatic activities, transcriptome, exoproteome, and coexpression networks of the T.

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is an opportunistic fungus, capable of causing Invasive Aspergillosis in immunocompromised patients, recently transplanted or undergoing chemotherapy. In the present work, we continued the investigation on AtfA-D transcription factors (TFs) characterizing possible genetic and physical interactions between them after normal growth and stressing conditions. We constructed double null mutants for all the possible combinations of Δ, and , and look into their susceptibility to different stressing conditions.

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Background: Unveiling fungal genome structure and function reveals the potential biotechnological use of fungi. Trichoderma harzianum is a powerful CAZyme-producing fungus. We studied the genomic regions in T.

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Brown rot fungi, such as (previously ), occur naturally in northern coniferous forest ecosystems and are known to be the most destructive group of decay fungi, degrading wood faster and more effectively than other wood-degrading organisms. It has been shown that brown rot fungi not only rely on enzymatic degradation of lignocellulose, but also use low molecular weight oxidative agents in a non-enzymatic degradation step prior to the enzymatic degradation. is used in standardized decay tests in both Europe and North America.

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Fungal plant cell wall degradation processes are governed by complex regulatory mechanisms, allowing the organisms to adapt their metabolic program with high specificity to the available substrates. While the uptake of representative plant cell wall mono- and disaccharides is known to induce specific transcriptional and translational responses, the processes related to early signal reception and transduction remain largely unknown. A fast and reversible way of signal transmission are post-translational protein modifications, such as phosphorylations, which could initiate rapid adaptations of the fungal metabolism to a new condition.

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Understanding relationships between genes responsible for enzymatic hydrolysis of cellulose and synergistic reactions is fundamental for improving biomass biodegradation technologies. To reveal synergistic reactions, the transcriptome, exoproteome, and enzymatic activities of extracts from Trichoderma harzianum, Trichoderma reesei and Trichoderma atroviride under biodegradation conditions were examined. This work revealed co-regulatory networks across carbohydrate-active enzyme (CAZy) genes and secreted proteins in extracts.

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Background: Trichoderma harzianum is used in biotechnology applications due to its ability to produce powerful enzymes for the conversion of lignocellulosic substrates into soluble sugars. Active enzymes involved in carbohydrate metabolism are defined as carbohydrate-active enzymes (CAZymes), and the most abundant family in the CAZy database is the glycoside hydrolases. The enzymes of this family play a fundamental role in the decomposition of plant biomass.

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The phytopathogen causes economic losses in important agricultural crops. Xylem vessel occlusion caused by biofilm formation is the major mechanism underlying the pathogenicity of distinct strains of . Here, we provide a detailed characterization of the extracellular proteins of .

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The subsp strain 9a5c is a Gram-negative, xylem-limited bacterium that is able to form a biofilm and affects citrus crops in Brazil. Some genes are considered to be involved in biofilm formation, but the specific mechanisms involved in this process remain unknown. This limited understanding of how some bacteria form biofilms is a major barrier to our comprehension of the progression of diseases caused by biofilm-producing bacteria.

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Background: The conversion of biomass-derived sugars via enzymatic hydrolysis for biofuel production is a challenge. Therefore, the search for microorganisms and key enzymes that increase the efficiency of the saccharification of cellulosic substrates remains an important and high-priority area of study. Trichoderma harzianum is an important fungus known for producing high levels of cellulolytic enzymes that can be used for cellulosic ethanol production.

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Xylella fastidiosa strain 9a5c is a gram-negative phytopathogen that is the causal agent of citrus variegated chlorosis (CVC), a disease that is responsible for economic losses in Brazilian agriculture. The most well-known mechanism of pathogenicity for this bacterial pathogen is xylem vessel occlusion, which results from bacterial movement and the formation of biofilms. The molecular mechanisms underlying the virulence caused by biofilm formation are unknown.

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Trichoderma harzianum IOC-3844 secretes high levels of cellulolytic-active enzymes and is therefore a promising strain for use in biotechnological applications in second-generation bioethanol production. However, the T. harzianum biomass degradation mechanism has not been well explored at the genetic level.

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Profiling the transcriptome that underlies biomass degradation by the fungus Trichoderma harzianum allows the identification of gene sequences with potential application in enzymatic hydrolysis processing. In the present study, the transcriptome of T. harzianum IOC-3844 was analyzed using RNA-seq technology.

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The 5'-nucleotidases constitute a ubiquitous family of enzymes that catalyze either the hydrolysis or the transfer of esterified phosphate at the 5' position of nucleoside monophosphates. These enzymes are responsible for the regulation of nucleotide and nucleoside levels in the cell and can interfere with the phosphorylation-dependent activation of nucleoside analogs used in therapies targeting solid tumors and viral infections. In the present study, we report the initial biochemical and functional characterization of a 5'-nucleotidase from Xylella fastidiosa that is related to the human cytosolic 5'-nucleotidase I.

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