Publications by authors named "Gilvan F da Silva"

Cryptococcosis is a fungal infection for which treatment relies on old antifungal agents usually leading to drawbacks such as high toxicity and mainly low efficiency since drug resistance of microorganisms is strongly widespread. The discovery of new antifungal agents is urgent and investigations about underexplored Natural Product (NP) can yield the necessary outcomes to guide the discovery of new prototypes to anti-cryptococcal molecules development. In this scenario, an integrated strategy involving metabolomic data analysis, biological assessement and genome mining of P.

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Toxic metal pollution in the Amazon is a serious problem that reduces the quality of water, soil, air, and consequently alters communities of fauna, flora, and microbiota, harming human health and well-being. Our aim was to determine the impact of toxic metals on the structure of the bacterial community associated with Diplopoda in the Amazon rainforest. Animals were kept in microcosms contaminated with cadmium (50 mg.

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microbeMASST, a taxonomically informed mass spectrometry (MS) search tool, tackles limited microbial metabolite annotation in untargeted metabolomics experiments. Leveraging a curated database of >60,000 microbial monocultures, users can search known and unknown MS/MS spectra and link them to their respective microbial producers via MS/MS fragmentation patterns. Identification of microbe-derived metabolites and relative producers without a priori knowledge will vastly enhance the understanding of microorganisms' role in ecology and human health.

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Pigments of fungal origin have aroused increasing interest in the food dye and cosmetic industries since the global demand for natural dyes has grown. Endophytic microorganisms are a source of bioactive compounds, and Amazonian plant species can harbor fungi with a wide range of biotechnological applications. Popularly known in Brazil as crajiru, is a medicinal plant that produces a red pigment.

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The growing interest in health and well-being has spurred the evolution of functional foods, which provide enhanced health benefits beyond basic nutrition. Guaraná seeds () have been widely studied and used as a functional food due to their richness in caffeine, phenolic compounds, amino acids, and other nutrients. This has established guaraná as a significant food supplement, with Brazil being the largest producer of the world.

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MicrobeMASST, a taxonomically-informed mass spectrometry (MS) search tool, tackles limited microbial metabolite annotation in untargeted metabolomics experiments. Leveraging a curated database of >60,000 microbial monocultures, users can search known and unknown MS/MS spectra and link them to their respective microbial producers via MS/MS fragmentation patterns. Identification of microbial-derived metabolites and relative producers, without knowledge, will vastly enhance the understanding of microorganisms' role in ecology and human health.

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The peach palm (Bactris gasipaes Kunth) is a palm of great importance to the population of the Brazilian Amazon region. Its fruits are an important food source for the local population (Alves and Flores, 1982). Between 2018 and 2021, peach palm fruits with black rot symptoms were collected in the state of Pará, in the municipalities of Juruti (02 09' 08'' S 56 05' 32W) and Santarém (2 26' 22''S 54 41' 55''W), Brazil.

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The genus Trichoderma comprises more than 500 valid species and is commonly used in agriculture for the control of plant diseases. In the present study, a Trichoderma species isolated from Scleronema micranthum (Malvaceae) has been extensively characterized and the morphological and phylogenetic data support the proposition of a new fungal species herein named Trichoderma agriamazonicum. This species inhibited the mycelial growth of all the nine phytopathogens tested both by mycoparasitism and by the production of VOCs, with a highlight for the inhibition of Corynespora cassiicola and Colletotrichum spp.

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Trichoderma is recognized as a prolific producer of nonribosomal peptides (NRPs) known as peptaibols, which have remarkable biological properties, such as antimicrobial and anticancer activities, as well as the ability to promote systemic resistance in plants against pathogens. In this study, the sequencing of 11-, 14- and 15-res peptaibols produced by a marine strain of isolated from the ascidian was performed via liquid chromatography coupled to high-resolution tandem mass spectrometry (LC-MS/MS). Identification, based on multilocus phylogeny, revealed that our isolate belongs to the species , which has never been reported in marine environments.

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Fungi of the genus Penicillium section Sclerotiora have as their main characteristic the presence of orange-pigmented mycelium, which is associated with sclerotiorin, a chlorinated secondary metabolite of the azaphilone subclass of polyketides. Sclerotiorin presents anti-diabetes, antioxidant, anti-inflammatory, anti-Alzheimer, antiviral, and antimicrobial activities, which has always attracted the attention of researchers worldwide. During our ongoing search for azaphilone-producing Amazonian fungi, the strain of Penicillium MMSRG-058 was isolated as an endophyte from the roots of Duguetia stelechantha and showed great capacity for producing sclerotiorin-like metabolites.

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Pelidnota luridipes Blanchard (1850) is a tropical beetle of the family Scarabaeidae, whose larvae live on wood without parental care. Microbiota of mid- and hindgut of larvae was evaluated by culture-dependent and independent methods, and the results show a diverse microbiota, with most species of bacteria and fungi shared between midgut and hindgut. We isolated 272 bacterial and 29 yeast isolates, identified in 57 and 7 species, respectively, while using metabarcoding, we accessed 1,481 and 267 OTUs of bacteria and fungi, respectively.

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The global increase in diseases transmitted by the vector , new and re-emerging, underscores the need for alternative and more effective methods of controlling mosquitoes. Our aim was to identify fungal strains from the Amazon rain forest that produce metabolites with larvicidal activity against . Thirty-six fungal strains belonging to 23 different genera of fungi, isolated from water samples collected in the state of Amazonas, Brazil were cultivated.

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The growing spread of dengue, chikungunya and Zika viruses demand the development of new and environmentally safe control methods for their vector, the mosquito Aedes aegypti. This study aims to find novel larvicidal agents from mutualistic (endophytic and rhizospheric) or edaphic bacteria that have no action against non-target organisms. Eleven out of the 254 bacterial strains tested were able to kill Ae.

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Scientific communication is facilitated by a data-driven, scientifically sound taxonomy that considers the end-user's needs and established successful practice. In 2013, the community voiced near unanimous support for a concept of that represented a clade comprising all agriculturally and clinically important species, including the species complex (FSSC). Subsequently, this concept was challenged in 2015 by one research group who proposed dividing the genus into seven genera, including the FSSC described as members of the genus , with subsequent justification in 2018 based on claims that the 2013 concept of is polyphyletic.

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This study examined how soil mercury contamination affected the structure and functionality of rhizobacteria communities from Aeschynomene fluminensis and Polygonum acuminatum and how rhizobacteria mediate metal bioremediation. The strains were isolated using culture-dependent methods, identified through 16S rDNA gene sequencing, and characterized with respect to their functional traits related to plant growth promotion and resistance to metals and antibiotics. The bioremediation capacity of the rhizobacteria was determined in greenhouse using corn plants.

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Endophytes improve the host performance in areas of high plant endemicity. Paullinia cupana is an Amazonia plant species of economic and social importance due to the high caffeine concentration in its seeds. An interesting strategy to identify endophytic microorganisms with potential biotechnological application is to understand the factors that influence the endophytic community to rationalize the host management programs.

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Endophytic bacteria occupy the same niche of phytopathogens and may produce metabolites that induce the host plant systemic resistance and growth. Host and environmental variables often determine the endophytic community's structure and composition. In this study, we addressed whether the plant genotype, organ, and geographic location influence the structure, composition, and functionality of endophytic bacterial communities in Paullinia cupana.

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Genetic manipulation of fungi requires quick, low-cost, efficient, high-throughput and molecular tools. In this paper, we report 22 entry constructs as new molecular tools based on the Gateway technology facilitating rapid construction of binary vectors that can be used for functional analysis of genes in fungi. The entry vectors for single, double or triple gene-deletion mutants were developed using hygromycin, geneticin and nourseothricin resistance genes as selection markers.

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Pseudocercospora fijiensis is the etiological agent of black Sigatoka, which is currently considered as one of the most destructive banana diseases in all locations where it occurs. It is estimated that a large portion of the P. fijiensis genome consists of transposable elements, which allows researchers to use transposon-based molecular markers in the analysis of genetic variability in populations of this pathogen.

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Background: Mycosphaerella fijiensis is a ascomycete that causes Black Sigatoka in bananas. Recently, the M. fijiensis genome was sequenced.

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