Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 3.158
Filtrar
1.
Appl Microbiol Biotechnol ; 105(18): 6707-6718, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34476516

RESUMO

Pneumocandin B0, the precursor of the antifungal drug caspofungin, is a lipohexapeptide produced by the fungus Glarea lozoyensis. Oxidative stress and the resulting production of reactive oxygen species (ROS) are known to be involved in the regulation of pneumocandin B0 biosynthesis. In this study, the Glyap1 gene of Glarea lozoyensis, a homologue of the yeast redox regulator YAP1, was knocked out. The intracellular ROS levels of the resulting ΔGlyap1 strain were higher than in the wild-type strain, which was caused by the downregulated expression of superoxide dismutase (SOD) and catalase (CAT). Compared with the wild-type strain, ΔGlyap1 exhibited an oxidative phenotype throughout its life cycle, which resulted in significantly higher pneumocandin B0 production per unit biomass. In addition, ΔGlyap1 showed growth inhibition and decreased pneumocandin B0 production in the presence of CCl4, which leads to strong oxidative stress. To overcome the strain's sensitivity, a three-stage antioxidant addition strategy was developed. This approach significantly improved the growth of ΔGlyap1 while maintaining a high pneumocandin B0 production per unit biomass, which reached 38.78 mg/g DCW. Notably, this result represents a 50% increase over the wild-type strain. These findings provide new insights into the regulatory mechanisms that control pneumocandin B0 production under oxidative stress, which may be applied to improve the production of other secondary metabolites. KEY POINTS: • Glyap1 is involved in expression of redox and pneumocandin B0 synthesis-related genes. • Addition of a three-stage antioxidant alleviated the sensitivity of ΔGlyap1 strain. • The yield of pneumocandin B0 per unit biomass of ΔGlyap1 strain was 38.78 mg/g DCW.


Assuntos
Ascomicetos , Equinocandinas , Ascomicetos/genética , Ascomicetos/metabolismo , Equinocandinas/metabolismo , Oxirredução , Estresse Oxidativo , Espécies Reativas de Oxigênio
2.
Appl Microbiol Biotechnol ; 105(18): 6793-6803, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34477943

RESUMO

Some microbial-associated molecular patterns (MAMPs), like glucan oligosaccharides, can be recognized by pattern recognition receptors (PRRs) of plant to elicit further immunity response. In this study, a novel glycoside hydrolase family 55 ß-1,3-glucanase (AcGluA) from Archangium sp. strain AC19 was cloned and expressed in Escherichia coli. Among the reported ß-1, 3-glucanases from the glycoside hydrolase 55 family, the purified AcGluA exhibited the highest activity on laminarin at pH 6.0 and 60 °C with 112.3 U/mg. Activity of AcGluA was stable in the range of pH 4.0-9.0 and at temperatures below 60 °C. The Km and Vmax of AcGluA for laminarin were 3.5 mg/ml and 263.5 µmol/(ml·min). AcGluA hydrolyzed laminarin into a series of oligosaccharides, suggesting it was an endo-ß-1,3-glucanase. The high dose of oligosaccharides (1600 mg/l) had conspicuous biocontrol efficacy on the defense of rice seedlings to Magnaporthe oryzae, which provided a new idea for the development of green biopesticide.Key points• The AcGluA was determined bacteria-derived ß-1,3-glucanases in the GH55 family.• The AcGluA showed the highest activity towards laminarin among reported GH55 family.• The hydrolysates of laminarin showed conspicuous biocontrol efficacy to M. oryzae.


Assuntos
Ascomicetos , Glicosídeo Hidrolases , Ascomicetos/metabolismo , Clonagem Molecular , Escherichia coli/genética , Escherichia coli/metabolismo , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Hidrólise , Especificidade por Substrato
3.
Molecules ; 26(15)2021 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-34361574

RESUMO

The plant endophyte Chalara sp. is able to biotransform the epigenetic modifier vorinostat to form unique, aniline-containing polyketides named chalanilines. Here, we sought to expand the chemical diversity of chalaniline A-type molecules by changing the aniline moiety in the precursor vorinostat. In total, twenty-three different vorinostat analogs were prepared via two-step synthesis, and nineteen were incorporated by the fungus into polyketides. The highest yielding substrates were selected for large-scale precursor-directed biosynthesis and five novel compounds, including two fluorinated chalanilines, were isolated, purified, and structurally characterized. Structure elucidation relied on 1D and 2D NMR techniques and was supported by low- and high-resolution mass spectrometry. All compounds were tested for their bioactivity but were not active in antimicrobial or cell viability assays. Aminofulvene-containing natural products are rare, and this high-yielding, precursor-directed process allows for the diversification of this class of compounds.


Assuntos
Compostos de Anilina , Ascomicetos , Endófitos , Hidrocarbonetos Fluorados , Compostos de Anilina/química , Compostos de Anilina/metabolismo , Ascomicetos/química , Ascomicetos/metabolismo , Endófitos/química , Endófitos/metabolismo , Hidrocarbonetos Fluorados/química , Hidrocarbonetos Fluorados/metabolismo
4.
Commun Biol ; 4(1): 871, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-34267314

RESUMO

Fungal biotechnology is set to play a keystone role in the emerging bioeconomy, notably to address pollution issues arising from human activities. Because they preserve biological diversity, Biological Resource Centres are considered as critical infrastructures to support the development of biotechnological solutions. Here, we report the first large-scale phenotyping of more than 1,000 fungal strains with evaluation of their growth and degradation potential towards five industrial, human-designed and recalcitrant compounds, including two synthetic dyes, two lignocellulose-derived compounds and a synthetic plastic polymer. We draw a functional map over the phylogenetic diversity of Basidiomycota and Ascomycota, to guide the selection of fungal taxa to be tested for dedicated biotechnological applications. We evidence a functional diversity at all taxonomic ranks, including between strains of a same species. Beyond demonstrating the tremendous potential of filamentous fungi, our results pave the avenue for further functional exploration to solve the ever-growing issue of ecosystems pollution.


Assuntos
Biotecnologia/métodos , Corantes/metabolismo , Fungos/metabolismo , Microbiologia Industrial/métodos , Lignina/metabolismo , Plásticos/metabolismo , Ascomicetos/classificação , Ascomicetos/genética , Ascomicetos/metabolismo , Basidiomycota/classificação , Basidiomycota/genética , Basidiomycota/metabolismo , Fungos/classificação , Fungos/genética , Variação Genética , Geografia , Humanos , Fenótipo , Filogenia , Especificidade da Espécie
5.
Molecules ; 26(12)2021 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-34205516

RESUMO

Neurodegenerative disorders, including Tauopathies that involve tau protein, base their pathological mechanism on forming proteinaceous aggregates, which has a deleterious effect on cells triggering an inflammatory response. Moreover, tau inhibitors can exert their mechanism of action through noncovalent and covalent interactions. Thus, Michael's addition appears as a feasible type of interaction involving an α, ß unsaturated carbonyl moiety to avoid pathological confirmation and further cytotoxicity. Moreover, we isolated three compounds from Antarctic lichens Cladonia cariosa and Himantormia lugubris: protolichesterinic acid (1), fumarprotocetraric acid (2), and lichesterinic acid (3). The maleimide cysteine labeling assay showed that compounds 1, 2, and 3 inhibit at 50 µM, but compounds 2 and 3 are statistically significant. Based on its inhibition capacity, we decided to test compound 2 further. Thus, our results suggest that compound 2 remodel soluble oligomers and diminish ß sheet content, as demonstrated through ThT experiments. Hence, we added externally treated oligomers with compound 2 to demonstrate that they are harmless in cell culture. First, the morphology of cells in the presence of aggregates does not suffer evident changes compared to the control. Additionally, the externally added aggregates do not provoke a substantial LDH release compared to the control, indicating that treated oligomers do not provoke membrane damage in cell culture compared with aggregates alone. Thus, in the present work, we demonstrated that Michael's acceptors found in lichens could serve as a scaffold to explore different mechanisms of action to turn tau aggregates into harmless species.


Assuntos
Fumaratos/farmacologia , Agregados Proteicos/efeitos dos fármacos , Proteínas tau/antagonistas & inibidores , Proteínas tau/metabolismo , 4-Butirolactona/análogos & derivados , 4-Butirolactona/farmacologia , Regiões Antárticas , Ascomicetos/metabolismo , Linhagem Celular Tumoral , Humanos , Líquens/metabolismo , Doenças Neurodegenerativas/tratamento farmacológico , Doenças Neurodegenerativas/metabolismo , Parmeliaceae/metabolismo , Tauopatias/tratamento farmacológico , Tauopatias/metabolismo
6.
Int J Mol Sci ; 22(13)2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-34281204

RESUMO

Verticillium dahliae is a soil-borne plant pathogenic fungus that causes Verticillium wilt on hundreds of dicotyledonous plant species. V. dahliae is considered an asexually (clonal) reproducing fungus, although both mating type idiomorphs (MAT1-1 and MAT1-2) are present, and is heterothallic. Most of the available information on V. dahliae strains, including their biology, pathology, and genomics comes from studies on isolates with the MAT1-2 idiomorph, and thus little information is available on the MAT1-1 V. dahliae strains in the literature. We therefore evaluated the growth responses of MAT1-1 and MAT1-2 V. dahliae strains to various stimuli. Growth rates and melanin production in response to increased temperature, alkaline pH, light, and H2O2 stress were higher in the MAT1-2 strains than in the MAT1-1 strains. In addition, the MAT1-2 strains showed an enhanced ability to degrade complex polysaccharides, especially starch, pectin, and cellulose. Furthermore, several MAT1-2 strains from both potato and sunflower showed increased virulence on their original hosts, relative to their MAT1-1 counterparts. Thus, compared to MAT1-1 strains, MAT1-2 strains derive their potentially greater fitness from an increased capacity to adapt to their environment and exhibit higher virulence. These competitive advantages might explain the current abundance of MAT1-2 strains relative to MAT1-1 strains in the agricultural and sylvicultural ecosystems, and this study provides the baseline information on the two mating idiomorphs to study sexual reproduction in V. dahliae under natural and laboratory conditions.


Assuntos
Ascomicetos/fisiologia , Ascomicetos/genética , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/metabolismo , Proteínas Fúngicas/metabolismo , Genes Fúngicos Tipo Acasalamento , Genômica , Doenças das Plantas/microbiologia , Reprodução Assexuada , Virulência
7.
Enzyme Microb Technol ; 149: 109854, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34311891

RESUMO

Xylanases are categorized into different family groups, two of which are glycoside hydrolases 10 (GH10) and 11 (GH11) families. These well-characterized xylanases demonstrate different modes of action in hydrolysis of xylans. Imitating certain types of microorganisms to produce bifunctional enzymes such as engineered xylanases has gained considerable attention among researchers. In this study, a recombinant chimeric enzyme (X11-10) was designed by fusing two thermostable xylanases through a peptide linker. The recombinant parental enzymes, xylanase 10 from fungus Bispora sp. MEY-1 (X10) and xylanase 11 from bacterium Thermobacillus xylanilyticus (X11), and their chimera were successfully expressed in Pichia pastoris (P. pastoris), purified, and characterized. Being active over a wide pH range, X11-10 chimera showed higher thermal stability, possessed a lower Km, and a higher catalytic efficiency (kcat/Km) in comparison to the parental enzymes. Also, molecular dynamics simulation (MDS) of X11-10 revealed that its active site residues were free to interact with substrate. This novel chimeric xylanase may have potential applications in different industrial processes since it can substitute two separate enzymes and therefore minimize the production costs.


Assuntos
Ascomicetos , Xilanos , Ascomicetos/metabolismo , Bacillales , Quimera/metabolismo , Endo-1,4-beta-Xilanases/genética , Endo-1,4-beta-Xilanases/metabolismo , Estabilidade Enzimática , Glicosídeo Hidrolases , Proteínas Recombinantes de Fusão/genética , Saccharomycetales , Especificidade por Substrato
8.
Int J Mol Sci ; 22(14)2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34298948

RESUMO

Verticillium wilt, caused by Verticillium dahliae, is a devastating disease for many important crops, including cotton. Kiwellins (KWLs), a group of cysteine-rich proteins synthesized in many plants, have been shown to be involved in response to various phytopathogens. To evaluate genes for their function in resistance to Verticillium wilt, we investigated KWL homologs in cotton. Thirty-five KWL genes (GhKWLs) were identified from the genome of upland cotton (Gossypium hirsutum). Among them, GhKWL1 was shown to be localized in nucleus and cytosol, and its gene expression is induced by the infection of V. dahliae. We revealed that GhKWL1 was a positive regulator of GhERF105. Silencing of GhKWL1 resulted in a decrease, whereas overexpression led to an increase in resistance of transgenic plants to Verticillium wilt. Interestingly, through binding to GhKWL1, the pathogenic effector protein VdISC1 produced by V. dahliae could impair the defense response mediated by GhKWL1. Therefore, our study suggests there is a GhKWL1-mediated defense response in cotton, which can be hijacked by V. dahliae through the interaction of VdISC1 with GhKWL1.


Assuntos
Ascomicetos , Proteínas Fúngicas , Regulação Fúngica da Expressão Gênica , Gossypium , Doenças das Plantas , Fatores de Transcrição , Regulação para Cima , Fatores de Virulência , Ascomicetos/genética , Ascomicetos/metabolismo , Ascomicetos/patogenicidade , Proteínas Fúngicas/biossíntese , Proteínas Fúngicas/genética , Gossypium/genética , Gossypium/metabolismo , Gossypium/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Fatores de Transcrição/biossíntese , Fatores de Transcrição/genética , Fatores de Virulência/biossíntese , Fatores de Virulência/genética
9.
Molecules ; 26(11)2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34072211

RESUMO

Fungi have become an invaluable source of bioactive natural products, with more than 5 million species of fungi spanning the globe. Fractionation of crude extract of Neodidymelliopsis sp., led to the isolation of a novel polyketide, (2Z)-cillifuranone (1) and five previously reported natural products, (2E)-cillifuranone (2), taiwapyrone (3), xylariolide D (4), pachybasin (5), and N-(5-hydroxypentyl)acetamide (6). It was discovered that (2Z)-cillifuranone (1) was particularly sensitive to ambient temperature and light resulting in isomerisation to (2E)-cillifuranone (2). Structure elucidation of all the natural products were conducted by NMR spectroscopic techniques. The antimicrobial activity of 2, 3, and 5 were evaluated against a variety of bacterial and fungal pathogens. A sodium [1-13C] acetate labelling study was conducted on Neodidymelliopsis sp. and confirmed that pachybasin is biosynthesised through the acetate polyketide pathway.


Assuntos
Ascomicetos/metabolismo , Produtos Biológicos/química , Policetídeos/isolamento & purificação , Acetamidas/química , Antraquinonas/química , Antibacterianos/química , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Bactérias/metabolismo , Isótopos de Carbono/química , Fermentação , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Policetídeos/química , Sódio/química , Acetato de Sódio , Espectrometria de Massas por Ionização por Electrospray
10.
Chem Biodivers ; 18(8): e2100314, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34101351

RESUMO

One new dioxolanone derivative, guignardianone G (1) and twelve known compounds (2-13) were isolated from the 95 % ethanol extract of the plant endophytic fungus Phyllosticta capitalensis cultured in rice medium. Among these known compounds, isoaltenuene (3), brassicasterol (7), 5,6-epoxyergosterol (8), citreoanthrasteroid A (9), demethylincisterol A (10), and chaxine C (11) were reported from Phyllosticta sp. for the first time. The structure of 1 was elucidated by 1D- and 2D-NMR experiments and HR-ESI-MS data analysis, and its absolute configuration was established through the comprehensive use of the methods of modified Mosher methods, calculations of ECD spectra and optical rotation values. The neuroprotective activity of compounds (1-9, 11-13) were evaluated on PC12 cells damage induced by glutamate, and compounds 9 and 12 showed potential neuroprotective activities with half effective concentration (EC50 ) of 24.2 and 33.9 µM, respectively.


Assuntos
Ascomicetos/química , Hamamelidaceae/microbiologia , Fármacos Neuroprotetores/química , Animais , Ascomicetos/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Dicroísmo Circular , Dioxolanos/química , Dioxolanos/isolamento & purificação , Dioxolanos/farmacologia , Endófitos , Ácido Glutâmico/farmacologia , Espectroscopia de Ressonância Magnética , Conformação Molecular , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Fármacos Neuroprotetores/isolamento & purificação , Fármacos Neuroprotetores/farmacologia , Células PC12 , Ratos
11.
PLoS Pathog ; 17(6): e1009657, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34133468

RESUMO

GTP-binding protein (G-protein) and regulator of G-protein signaling (RGS) mediated signal transduction are critical in the growth and virulence of the rice blast pathogen Magnaporthe oryzae. We have previously reported that there are eight RGS and RGS-like proteins named MoRgs1 to MoRgs8 playing distinct and shared regulatory functions in M. oryzae and that MoRgs1 has a more prominent role compared to others in the fungus. To further explore the unique regulatory mechanism of MoRgs1, we screened a M. oryzae cDNA library for genes encoding MoRgs1-interacting proteins and identified MoCkb2, one of the two regulatory subunits of the casein kinase (CK) 2 MoCk2. We found that MoCkb2 and the sole catalytic subunit MoCka1 are required for the phosphorylation of MoRgs1 at the plasma membrane (PM) and late endosome (LE). We further found that an endoplasmic reticulum (ER) membrane protein complex (EMC) subunit, MoEmc2, modulates the phosphorylation of MoRgs1 by MoCk2. Interestingly, this phosphorylation is also essential for the GTPase-activating protein (GAP) function of MoRgs1. The balance among MoRgs1, MoCk2, and MoEmc2 ensures normal operation of the G-protein MoMagA-cAMP signaling required for appressorium formation and pathogenicity of the fungus. This has been the first report that an EMC subunit is directly linked to G-protein signaling through modulation of an RGS-casein kinase interaction.


Assuntos
Ascomicetos/metabolismo , Ascomicetos/patogenicidade , Proteínas Fúngicas/metabolismo , Interações Hospedeiro-Parasita/fisiologia , Virulência/fisiologia , Caseína Quinases/metabolismo , Fosforilação , Transdução de Sinais/fisiologia
12.
Fungal Biol ; 125(7): 532-540, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34140149

RESUMO

The N-end rule pathway is a regulated protein degradation system. Arthrobotrys oligospora, a typical nematode-trapping fungus, switches its life strategies from saprophytism to carnivorism when capturing free-living nematodes by means of adhesive networks. In this study, a putative E3-ligase AoUBR1 involved in N-end rule pathway was characterized in A. oligospora during vegetative growth and trap formation. Expression of AoUBR1 coding gene was down-regulated during trap formation. Compared with wild type, the AoUBR1 knock-out mutants decreased the vegetative growth, formed less traps, and turned to be sensitive to cold stress, while, AoUBR1 overexpression mutants lost the capacity to produce conidia and also formed less traps. A number of genes differentially expressed by knock-out and overexpression of AoUBR1, which lead to the transcriptional responses associated with plasma membrane, transportation, oxidation, and proteolysis. AoUBR1 knock-out also resulted in the down-regulation of numerous secreted proteins associated with carnivorism and nutrient utilization from nematodes. In addition, AoUBR1 homologs were conserved in nematode-trapping fungi based on the genome searching. Therefore, the results suggested AoUBR1 in A. oligospora and its homologs in other trapping fungi are involved in the lifestyle switch between saprophytism and carnivorism.


Assuntos
Ascomicetos , Ubiquitina-Proteína Ligases , Animais , Ascomicetos/enzimologia , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/metabolismo , Regulação Fúngica da Expressão Gênica , Técnicas de Inativação de Genes , Nematoides/microbiologia , Esporos Fúngicos/genética , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
13.
Fungal Biol ; 125(7): 576-584, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34140153

RESUMO

We inoculated Tuber aestivum and Tuber sinoaestivum on Carya illinoinensis to explore the effects of inoculation on host plant growth, enzyme activities, the physicochemical properties of rhizosphere soil, the denitrifying bacterial community in the rhizosphere, and the distribution of mating type genes in the rhizosphere. We found that the Tuber spp. inoculation increased the height of the host plant and that the stem circumference of the host was greater two months after inoculation. Six months after inoculation, the peroxidase activity of the seedlings inoculated with T. sinoaestivum was higher than that of the control. At four and six months after inoculation, the superoxidase dismutase activities of the seedlings inoculated with T. aestivum were higher than those of the seedlings inoculated with T. sinoaestivum. Six months after inoculation, nitrate nitrogen content was lowest in the control and highest in the T. sinoaestivum treatment. Among the nirS-type denitrifying bacteria community, the relative abundances of Proteobacteria were high. T. aestivum and T. sinoaestivum inoculation did not affect the diversity of denitrifying bacteria. The mating type genes MAT1-1-1 and MAT1-2-1 were detected in the rhizosphere of C. illinoinensis inoculated with T. sinoaestivum and T. aestivum, and MAT1-1-1 dominated over MAT1-2-1.


Assuntos
Ascomicetos , Carya , Interações entre Hospedeiro e Microrganismos , Ascomicetos/metabolismo , Carya/enzimologia , Carya/microbiologia , Rizosfera , Plântula/enzimologia , Plântula/microbiologia , Solo/química , Microbiologia do Solo , Superóxido Dismutase/metabolismo
14.
PLoS Genet ; 17(5): e1009137, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33999937

RESUMO

Polarized hyphal growth of filamentous pathogenic fungi is an essential event for host penetration and colonization. The long-range early endosomal trafficking during hyphal growth is crucial for nutrient uptake, sensing of host-specific cues, and regulation of effector production. Bin1/Amphiphysin/Rvs167 (BAR) domain-containing proteins mediate fundamental cellular processes, including membrane remodeling and endocytosis. Here, we identified a F-BAR domain protein (ArF-BAR) in the necrotrophic fungus Ascochyta rabiei and demonstrate its involvement in endosome-dependent fungal virulence on the host plant Cicer arietinum. We show that ArF-BAR regulates endocytosis at the hyphal tip, localizes to the early endosomes, and is involved in actin dynamics. Functional studies involving gene knockout and complementation experiments reveal that ArF-BAR is necessary for virulence. The loss-of-function of ArF-BAR gene results in delayed formation of apical septum in fungal cells near growing hyphal tip that is crucial for host penetration, and impaired secretion of a candidate effector having secretory signal peptide for translocation across the endoplasmic reticulum membrane. The mRNA transcripts of ArF-BAR were induced in response to oxidative stress and infection. We also show that ArF-BAR is able to tubulate synthetic liposomes, suggesting the functional role of F-BAR domain in membrane tubule formation in vivo. Further, our studies identified a stress-induced transcription factor, ArCRZ1 (Calcineurin-responsive zinc finger 1), as key transcriptional regulator of ArF-BAR expression. We propose a model in which ArCRZ1 functions upstream of ArF-BAR to regulate A. rabiei virulence through a mechanism that involves endocytosis, effector secretion, and actin cytoskeleton regulation.


Assuntos
Actinas/metabolismo , Ascomicetos/citologia , Ascomicetos/patogenicidade , Cicer/microbiologia , Endocitose , Proteínas Fúngicas/metabolismo , Ascomicetos/genética , Ascomicetos/metabolismo , Núcleo Celular/metabolismo , Citoesqueleto/metabolismo , Endocitose/genética , Endossomos/metabolismo , Proteínas Fúngicas/genética , Regulação Fúngica da Expressão Gênica , Lipossomos/metabolismo , Mutação , Estresse Oxidativo , Doenças das Plantas/microbiologia , Regiões Promotoras Genéticas/genética , Virulência/genética
15.
Food Chem ; 360: 130120, 2021 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-34034050

RESUMO

Methyl salicylate (MeSA) is a plant metabolite that induces plant defence resistance and an odorous volatile compound presenting green nuances. This volatile compound was shown to be present in wine samples, sometimes at concentrations above its olfactory detection threshold. MeSA is localized in grapes, particularly in the skins and stems, and is extracted during red wine vinification. It was detected at the highest concentrations in wines of several grape varieties, made from grapes affected by cryptogamic diseases, namely downy mildew caused by Plasmopara viticola, and black rot caused by Guignardia bidwellii. It has also been detected in wines from vines affected by Esca, a Grapevine Trunk Disease. MeSA can also be considered to be a chemical marker in grapes and wine indicative of the level of development of several vine cryptogamic diseases.


Assuntos
Salicilatos/análise , Vitis/química , Vinho/análise , Ascomicetos/crescimento & desenvolvimento , Ascomicetos/metabolismo , Cromatografia Líquida de Alta Pressão , Frutas/química , Frutas/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Doenças das Plantas/microbiologia , Salicilatos/isolamento & purificação , Extração em Fase Sólida , Paladar/fisiologia , Vitis/metabolismo
16.
Molecules ; 26(9)2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33946466

RESUMO

The species Pseudogymnoascus is known as a psychrophilic pathogenic fungus which is ubiquitously distributed in Antarctica. While the studies of its secondary metabolites are infrequent. Systematic research of the metabolites of the Antarctic fungus Pseudogymnoascus sp. HSX2#-11 led to the isolation of one new pyridine derivative, 4-(2-methoxycarbonyl-ethyl)-pyridine-2-carboxylic acid methyl ester (1), together with one pyrimidine, thymine (2), and eight diketopiperazines, cyclo-(dehydroAla-l-Val) (3), cyclo-(dehydroAla-l-Ile) (4), cyclo-(dehydroAla-l-Leu) (5), cyclo-(dehydroAla-l-Phe) (6), cyclo-(l-Val-l-Phe) (7), cyclo-(l-Leu-l-Phe) (8), cyclo-(l-Trp-l-Ile) (9) and cyclo-(l-Trp-l-Phe) (10). The structures of these compounds were established by extensive spectroscopic investigation, as well as by detailed comparison with literature data. This is the first report to discover pyridine, pyrimidine and diketopiperazines from the genus of Pseudogymnoascus.


Assuntos
Ascomicetos/química , Compostos de Nitrogênio/análise , Regiões Antárticas , Ascomicetos/metabolismo , Produtos Biológicos/química , Estrutura Molecular , Compostos de Nitrogênio/química , Metabolismo Secundário
17.
Int J Biol Macromol ; 183: 145-157, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-33878360

RESUMO

Two novel glucans named MIPB50-W and MIPB50-S-1 were obtained from edible Morchella importuna with molecular weights (Mw) of 939.2 kDa and 444.5 kDa, respectively. MIPB50-W has a backbone of α-(1 → 4)-d-glucan, which was substituted at O-6 position by α-d-Glcp-(1→. Moreover, MIPB50-S-1 has a backbone of α-(1 → 4)-d-glucan, which was substituted at O-6 position by α-d-Glcp-(1 → 6)-α-d-Glcp-(1→. This is the first report about glucan found in Morchella mushrooms. Furthermore, MIPB50-W and MIPB50-S-1 strengthened the phagocytosis function and the promoted secretion of interleukins (IL)-6/tumor necrosis factor-alpha (TNF-α) and nitric oxide (NO), which induced the activation of Toll-like receptor 2 (TLR2), TLR4 as well as mitogen activated protein kinase (MAPK) and nuclear factor-κB (NF-κB) pathways. Interestingly, MIPB50-S-1 performed the better immunomodulatory activity than that of MIPB50-W in almost all tests. Therefore, MIPB50-W and MIPB50-S-1 are potential immune-enhancing components of functional foods.


Assuntos
Ascomicetos/metabolismo , Carpóforos/metabolismo , Glucanos/farmacologia , Fatores Imunológicos/farmacologia , Macrófagos/efeitos dos fármacos , Animais , Glucanos/química , Glucanos/isolamento & purificação , Fatores Imunológicos/química , Fatores Imunológicos/isolamento & purificação , Interleucina-6/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Estrutura Molecular , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Fagocitose/efeitos dos fármacos , Células RAW 264.7 , Transdução de Sinais , Relação Estrutura-Atividade , Receptor 2 Toll-Like/metabolismo , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
18.
Genes (Basel) ; 12(4)2021 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-33919788

RESUMO

Brown rot is the most economically important fungal disease of stone fruits and is primarily caused by Monilinia laxa and Monlinia fructicola. Both species co-occur in European orchards although M. fructicola is considered to cause the most severe yield losses in stone fruit. This study aimed to generate a high-quality genome of M. fructicola and to exploit it to identify genes that may contribute to pathogen virulence. PacBio sequencing technology was used to assemble the genome of M. fructicola. Manual structural curation of gene models, supported by RNA-Seq, and functional annotation of the proteome yielded 10,086 trustworthy gene models. The genome was examined for the presence of genes that encode secreted proteins and more specifically effector proteins. A set of 134 putative effectors was defined. Several effector genes were cloned into Agrobacterium tumefaciens for transient expression in Nicotiana benthamiana plants, and some of them triggered necrotic lesions. Studying effectors and their biological properties will help to better understand the interaction between M. fructicola and its stone fruit host plants.


Assuntos
Ascomicetos/patogenicidade , Proteínas Fúngicas/genética , Perfilação da Expressão Gênica/métodos , Análise de Sequência de DNA/métodos , Ascomicetos/genética , Ascomicetos/metabolismo , Curadoria de Dados , Europa (Continente) , Regulação Fúngica da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Anotação de Sequência Molecular , Metabolismo Secundário , Análise de Sequência de RNA , Virulência
19.
Plant Cell ; 33(4): 1319-1340, 2021 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-33793825

RESUMO

In plants, chitin-triggered immunity is one of the first lines of defense against fungi, but phytopathogenic fungi have developed different strategies to prevent the recognition of chitin. Obligate biotrophs such as powdery mildew fungi suppress the activation of host responses; however, little is known about how these fungi subvert the immunity elicited by chitin. During epiphytic growth, the cucurbit powdery mildew fungus Podosphaera xanthii expresses a family of candidate effector genes comprising nine members with an unknown function. In this work, we examine the role of these candidates in the infection of melon (Cucumis melo L.) plants, using gene expression analysis, RNAi silencing assays, protein modeling and protein-ligand predictions, enzymatic assays, and protein localization studies. Our results show that these proteins are chitinases that are released at pathogen penetration sites to break down immunogenic chitin oligomers, thus preventing the activation of chitin-triggered immunity. In addition, these effectors, designated effectors with chitinase activity (EWCAs), are widely distributed in pathogenic fungi. Our findings reveal a mechanism by which fungi suppress plant immunity and reinforce the idea that preventing the perception of chitin by the host is mandatory for survival and development of fungi in plant environments.


Assuntos
Ascomicetos/patogenicidade , Quitina/metabolismo , Quitinases/metabolismo , Cucumis melo/microbiologia , Imunidade Vegetal/fisiologia , Ascomicetos/citologia , Ascomicetos/genética , Ascomicetos/metabolismo , Parede Celular/metabolismo , Quitina/imunologia , Quitinases/química , Quitinases/genética , Cucumis melo/metabolismo , Proteínas Fúngicas/genética , Proteínas Fúngicas/metabolismo , Regulação Fúngica da Expressão Gênica , Inativação Gênica , Interações Hospedeiro-Patógeno/fisiologia , Família Multigênica , Filogenia , Doenças das Plantas/microbiologia
20.
Int J Mol Sci ; 22(5)2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33807984

RESUMO

Black root rot (BRR) is an economically important disease of cotton and other crops, especially in cooler regions with short growing seasons. Symptoms include black discoloration of the roots, reduced number of lateral roots and stunted or slow plant growth. The cultivated tetraploid Gossypium species are susceptible to BRR. Resistance to BRR was identified in G. arboreum accession BM13H and is associated with reduced and restricted hyphal growth and less sporulation. Transcriptome analysis indicates that BM13H responds to infection at early time points 2- and 3-days post-inoculation, but by day 5, few differentially expressed genes are observed between infected and uninfected roots. Inheritance of BM13H resistance to BRR was evaluated in an F6 recombinant inbred population and shows a single semi-dominant locus conferring resistance that was fine mapped to a region on chromosome 1, containing ten genes including five putative resistance-like genes.


Assuntos
Ascomicetos/metabolismo , Mapeamento Cromossômico , Resistência à Doença/genética , Gossypium , Doenças das Plantas , Raízes de Plantas , Regulação da Expressão Gênica de Plantas , Gossypium/genética , Gossypium/metabolismo , Gossypium/microbiologia , Doenças das Plantas/genética , Doenças das Plantas/microbiologia , Raízes de Plantas/genética , Raízes de Plantas/metabolismo , Raízes de Plantas/microbiologia , Tetraploidia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...