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1.
J Mech Behav Biomed Mater ; 125: 104934, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34773913

RESUMO

Armillaria ostoyae (Romagn.) Herink is a highly pathogenic fungus that uses exploratory, cordlike structures called rhizomorphs to seek out new sources of nutrition, posing a parasitic threat to natural stands of trees, orchards, and vineyards. Rhizomorphs are notoriously difficult to destroy, and this resilience is due in large part to a melanized layer that protects the rhizomorph. While this structure has been previously observed, its structural and chemical defenses are yet to be discerned. Research was conducted on both lab-cultured and wild-harvested rhizomorph samples. While both environments produce rhizomorphs, only the wild-harvested rhizomorphs produced the melanized layer, allowing for direct investigation of its structure and properties. Imaging, chemical analysis, mechanical testing, and finite element modeling were used to understand the defense mechanisms provided by the melanized layer. Imaging showed a porous outer layer in both types of rhizomorphs, though the pores were smaller in the harvested melanized layer. This melanized layer contained calcium, which provides chemical defense against both human and natural control methods, but was absent from cultured samples. Nanoindentation resulted in a larger variance of hardness values for cultured rhizomorphs than for wild-harvested. Finite element analysis proved that the smaller pore structure of the melanized porous layer had the best balance between maximum deformation and resulting permanent deformation. These results allow for a better understanding of the defenses of this pathogenic fungus, which may lead to better control methods.


Assuntos
Árvores , Armillaria , Humanos
2.
Ulster Med J ; 90(3): 168-174, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34815596

RESUMO

Antimicrobial resistance (AMR) has now emerged as a major global public health problem. Certain bacterial pathogens, particularly Gram negative organisms associated with patients with cystic fibrosis (CF), have become resistant to several classes of antibiotics resulting in pan-resistance, which creates a clinical treatment dilemma. This study wished to explore the production of antibacterial extracellular metabolites from plant pathogenic fungi. Fungal Culture Extracts (FCEs) were prepared from 10 fungi (Armillaria gallica, Clitocybe nebularis, Fusarium coeruleum, Fusarium oxysporum, Fusarium poae, Hymenoscyphus fraxineus, Nectria fuckeliana, Phytophthora infestans, Phytophthora ramorum, Postia placenta), which were tested for activity against the CF pathogens, Pseudomonas aeruginosa (PA) (n=8), Burkholderia cenocepacia (n=2) and Stenotrophomonas maltophilia (n=2). In addition, FCE were assessed for their ability to alter antibiotic susceptibility in PA (n=8), with six antipseudomonal antibiotics (ceftazidime, ciprofloxacin, colistin, meropenem, piperacillin/tazobactam, tobramycin). None of the FCEs showed inhibitory activity to the 12 bacterial isolates tested, with the exception of the FCE from Postia placenta, which showed inhibition against all 12 bacteria. An antagonistic interaction was observed, where a statistically significant decrease in mean zone sizes was noted with Armillaria gallica (p=0.03) and Phytophthora infestans (p=0.03) FCEs and their interaction with the fluoroquinolone antibiotic, ciprofloxacin. Given the increase in clinical morbidity and mortality associated with chronic lung infections with Pseudomonas aeruginosa, Burkholderia cenocepacia and Stenotrophomonas maltophilia, coupled with the difficulty in treating such chronic infection due to overwhelming antimicrobial resistance, any novel substance showing inhibition of these organisms merits further investigation as a potential future antimicrobial agent, with potential clinical therapeutic application.


Assuntos
Basidiomycota , Burkholderia cenocepacia , Stenotrophomonas maltophilia , Agaricales , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Armillaria , Ascomicetos , Fungos , Fusarium , Humanos , Hypocreales , Polyporales , Pseudomonas aeruginosa
3.
Microb Biotechnol ; 14(5): 2187-2198, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34327850

RESUMO

Seventeen species of fungi belonging to thirteen genera were screened for the ability to carry out the transformation of 7-oxo-DHEA (7-oxo-dehydroepiandrosterone). Some strains expressed new patterns of catalytic activity towards the substrate, namely 16ß-hydroxylation (Laetiporus sulphureus AM498), Baeyer-Villiger oxidation of ketone in D-ring to lactone (Fusicoccum amygdali AM258) and esterification of the 3ß-hydroxy group (Spicaria divaricata AM423). The majority of examined strains were able to reduce the 17-oxo group of the substrate to form 3ß,17ß-dihydroxy-androst-5-en-7-one. The highest activity was reached with Armillaria mellea AM296 and Ascosphaera apis AM496 for which complete conversion of the starting material was achieved, and the resulting 17ß-alcohol was the sole reaction product. Two strains of tested fungi were also capable of stereospecific reduction of the conjugated 7-keto group leading to 7ß-hydroxy-DHEA (Inonotus radiatus AM70) or a mixture of 3ß,7α,17ß-trihydroxy-androst-5-ene and 3ß,7ß,17ß-trihydroxy-androst-5-ene (Piptoporus betulinus AM39). The structures of new metabolites were confirmed by MS and NMR analysis. They were also examined for their cholinesterase inhibitory activity in an enzymatic-based assay in vitro test.


Assuntos
Desidroepiandrosterona , Fungos , Armillaria , Ascomicetos , Onygenales , Polyporales
4.
Environ Sci Pollut Res Int ; 28(37): 51544-51555, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33982259

RESUMO

The aim of this study was to determine the element content of wild edible and inedible mushroom species (Agaricus campestris, Armillaria ostoyae, Boletus reticulatus, Bondarzewia mesenterica, Bovistella utriformis, Cantharellus cibarius, Marasmius oreades, Megacollybia platyphylla, Meripilus giganteus, Neoboletus erythropus, Panellus stipticus, Phaeotremella foliacea, Pleurotus ostreatus, Podoscypha multizonata, Russula aurea, R. chloroides, R. virescens, T. versicolor, Trametes gibbose, and Trichaptum biforme) collected from the Belgrad Forests and the Ilgaz Mountain National Park. Based on the results of elemental analyses, daily metal intake (DMI) and health risk index (HRI) values of edible mushrooms collected from both localities were also calculated. As, Cd, Cr, Se, P, Hg, Cu, Mn, Fe, Zn, Al, Ca, Mg, and K contents of mushrooms were in the ranges of 0.16-3.45, 0.09-2.4, 0.15-2.34, 0.3-8.13, 0.28-11.44, 14.03-37.81, 3.87-108.57, 6.18-149.77, 11.9-776.1, 5.4-317.4, 7.4-355.2, 15.4-3517.3, 266.0-2500.0, and 628.0-24083.0 mg/kg dry weight, respectively. As a result of the DMI and HRI analyses, Cu concentration of B. utriformis (DMI: 46.53 µg/kg body weight/serving, HRI: 1.16) and Cd concentrations of A. campestris (DMI: 0.49 µg/kg body weight/serving, HRI: 1.36), A. ostoyae (DMI: 1.03 µg/kg body weight/serving, HRI: 2.86), B. utriformis (DMI: 0.52 µg/kg body weight/serving, HRI: 1.44), and P. ostreatus (DMI: 0.45 µg/kg body weight/serving, HRI: 1.24) were found to exceed the legal limits determined by authorities. It was concluded that the species collected from the regions in question should be consumed in a controlled manner.


Assuntos
Agaricales , Agaricus , Armillaria , Basidiomycota , Monitoramento Ambiental , Florestas , Marasmius , Parques Recreativos , Polyporales , Trametes
5.
Sci Rep ; 11(1): 7336, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33795735

RESUMO

Species of Armillaria are distributed globally and include some of the most important pathogens of forest and ornamental trees. Some of them form large long-living clones that are considered as one of the largest organisms on earth and are capable of long-range spore-mediated transfer as well as vegetative spread by drought-resistant hyphal cords called rhizomorphs. However, the virus community infecting these species has remained unknown. In this study we used dsRNA screening and high-throughput sequencing to search for possible virus infections in a collection of Armillaria isolates representing three different species: Armillaria mellea from South Africa, A. borealis from Finland and Russia (Siberia) and A. cepistipes from Finland. Our analysis revealed the presence of both negative-sense RNA viruses and positive-sense RNA viruses, while no dsRNA viruses were detected. The viruses included putative new members of virus families Mymonaviridae, Botourmiaviridae and Virgaviridae and members of a recently discovered virus group tentatively named "ambiviruses" with ambisense bicistronic genomic organization. We demonstrated that Armillaria isolates can be cured of viruses by thermal treatment, which enables the examination of virus effects on host growth and phenotype using isogenic virus-infected and virus-free strains.


Assuntos
Armillaria/metabolismo , Armillaria/virologia , Fungos/metabolismo , Doenças das Plantas/microbiologia , Doenças das Plantas/virologia , Raízes de Plantas/microbiologia , Raízes de Plantas/virologia , Vírus de RNA/metabolismo , Biologia Computacional/métodos , Mapeamento de Sequências Contíguas , Finlândia , Genoma , Genoma Viral , Filogenia , Federação Russa , Sibéria , África do Sul , Especificidade da Espécie , Transcriptoma
6.
Biomolecules ; 11(4)2021 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-33920034

RESUMO

The present study aimed to investigate the chemical composition, bioactive compounds, and antioxidant activity of two wild edible mushrooms, the honey fungus (Armillaria mellea) and the parasol mushroom (Macrolepiota procera), collected from Northern Morocco (MA) and Portugal (PT). Those species were chosen due to their edibility, nutraceutical, and medicinal properties. Bioactive compounds (ascorbic acid, tannin, total phenolic, total flavonoid, ß-carotene, and lycopene) and their antioxidant activity were determined by spectrophotometric methods. Herein, the fruiting body of the samples revealed a significantly higher amount of bioactive compounds, and values varied between the Moroccan and the Portuguese ones. Methanolic extracts shown a strong antioxidant capacity: Using DPPH free radical-scavenging activity radicals (IC50 1.06-1.32 mg/mL); inhibition of ß-carotene bleaching radicals (IC50 0.09-0.53 mg/mL); and, reducing power radicals (IC50 0.52-1.11 mg/mL). The mushroom species with the highest antioxidant capacity was A. mellea from MA. Chemical composition was analyzed by GC-MS and LC-MS methodologies. GC-MS analysis showed that the most abundant biomolecules group was sugar compositions in the four samples (62.90%, 48.93%, 59.00%, and 53.71%) and the main components were galactitol 16.74%, petroselinic acid 19.83%, d-galactose 38.43%, and glycerol 24.43% in A. mellea (MA), A. mellea (PT), M. procera (MA), and M. procera (PT), respectively. LC-MS analysis of individual phenolic compounds revealed that vanillic acid (198.40 ± 2.82 µg/g dry weight (dw) and cinnamic acid (155.20 ± 0.97 µg/g dw) were the main compounds detected in A. mellea, while protocatechuic acid (92.52 ± 0.45 and 125.50 ± 0.89 µg/g dw) was predominated in M. procera for MA and PT samples, respectively. In general, the results of this comparative study demonstrate that the geographic and climatic conditions of the collection site can influence biomolecule compounds and antioxidant properties of wild mushrooms. This study contributes to the elaboration of nutritional, nutraceutical, and pharmaceutical databases of the worldwide consumed mushrooms.


Assuntos
Agaricales/química , Antioxidantes/química , Armillaria/química , Produtos Biológicos/química , Ácido Ascórbico/análise , Flavonoides/análise , Hidroxibenzoatos/análise , Licopeno/análise , Taninos/análise , beta Caroteno/análise
7.
Environ Sci Pollut Res Int ; 28(27): 36193-36204, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33687630

RESUMO

Wild edible mushrooms are very popular for both their flavors and nutritional values. However, some mushroom species can be harmful to human health as they accumulate some elements in excessive amounts. The aim of this study was to determine the concentrations of Al, Ca, Cd, Cr, Cu, Fe, K, Mg, Mn, P, Se, and Zn of some wild edible (Agaricus arvensis, A. bitorquis, A. sylvaticus, Amanita vaginata, Armillaria mellea, Clavariadelphus pistillaris, Clitocybe nebularis, Clitopilus prunulus, Hygrophorus marzuolus, H. russula, Lactarius volemus, Lycoperdon molle, and Macrolepiota mastoidea) and non-edible mushroom species (A. citrina, Auricularia mesenterica, Chanterellus melanoxeros, Chondrostereum purpureum, Clathrus ruber, L. controversus, L. helvus, and L. zonarius) collected from Belgrad forest (Istanbul, Turkey). Daily intakes of element (DIE) and health risk index (HRI) values of the edible mushroom species were also calculated. The concentrations of the elements in question were determined to be in the ranges of 9.7-556.8, 2.5-2226.7, 0.06-2.52, 0.03-13.17, 3.74-100.19, 13.3-507.4, 2635.0-28614.0, 493.0-2412.0, 6.97-3150.73, 0.29-13.26, 0.38-3.67, and 9.1-293.8 mg/kg, respectively. The Cd concentration of H. russula (DIE: 1.08, HRI: 1.08), Cr concentration of C. nebularis (DIE: 5.64, HRI: 1.88), and the Cu concentration of M. mastoidea (DIE: 42.94, HRI: 1.07) were above the reference values. The results showed that the long-term consumption of H. russula, C. nebularis, and M. mastoidea collected from Belgrad forest can have a negative impact on human health. Therefore, it was concluded that the element concentrations of edible wild mushrooms in this region should be examined periodically.


Assuntos
Agaricales , Agaricus , Amanita , Armillaria , Basidiomycota , Monitoramento Ambiental , Florestas , Humanos , Medição de Risco , Turquia
8.
Appl Environ Microbiol ; 87(12): e0027521, 2021 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-33741625

RESUMO

Tyrosinase is a bifunctional enzyme mediating the o-hydroxylation and two-electron oxidation of monophenols to o-quinones. The monophenolase activity of tyrosinase is much desired for the industrial synthesis of catechols. However, the generally low ratio of monophenolase/diphenolase activity of tyrosinase limited its utilization in the industry. In this study, a novel tyrosinase from Armillaria ostoyae strain C18/9 (AoTyr) was characterized, and the results showed that the enzyme has an optimal temperature of 25°C and an optimal pH of 6. The enzyme has comparable monophenolase and diphenolase activities and exhibits substrate inhibition in both of the activities. In silico analysis and mutagenesis experiments showed that residues 262 and 266 play important roles in modulating the substrate inhibition and enzymatic activities of AoTyr, and the replacement of D262 with asparagine significantly increased the monophenolase/diphenolase catalytic efficiencies (kcat/Km ratios) (1.63-fold) of the enzyme. The results from this study indicated that this novel tyrosinase could be a potential candidate for the industrial biosynthesis of catechols. IMPORTANCE Tyrosinase is able to oxidize various phenolic compounds, and its ability to convert monophenols into diphenols has caught great attention in the research field and industrial applications. However, the utilization of tyrosinase for the industrial synthesis of catechols has been limited due to the fact that the monophenolase activity of most of the known tyrosinases is much lower than the diphenolase activity. In the present study, a novel tyrosinase with comparable monophenolase and diphenolase activities was characterized. The enzyme exhibits substrate inhibition in both monophenolase and diphenolase activities. In silico analysis followed by mutagenesis experiments confirmed the important roles of residues 262 and 266 in the substrate inhibition and activity modulation of the enzyme, and the D262N variant showed an enhanced monophenolase/diphenolase catalytic efficiency ratio compared to the wild-type enzyme.


Assuntos
Armillaria/enzimologia , Proteínas Fúngicas , Monofenol Mono-Oxigenase , Sequência de Aminoácidos , Catálise , Clonagem Molecular , Simulação por Computador , Detergentes/química , Inibidores Enzimáticos/química , Escherichia coli/genética , Proteínas Fúngicas/antagonistas & inibidores , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Concentração de Íons de Hidrogênio , Metais/química , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/química , Monofenol Mono-Oxigenase/genética , Oxirredutases/química , Solventes/química , Especificidade por Substrato , Temperatura
9.
J Ethnopharmacol ; 265: 113395, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32956757

RESUMO

ETHNOPHARMACOLOGY RELEVANCE: Armillaria mellea (Vahl) P. Kumm. (AM) is an edible mushroom that has been reported as treatment for several neurological disorders, such as dizziness and epilepsy in Asia. Importantly, AM shares a symbiotic relationship with Gastrodia elata Blume (GE), a medicinal herb with antidepressant-like properties. Researchers believe that AM may possess pharmacological properties similar to GE due to their symbiosis, however, few studies have investigated the pharmacological effect of AM. AIM OF THE STUDY: The aim of this study was to explore the potential of AM as an antidepressant in forced-swimming test (FST) and unpredictable chronic mild stress (UCMS) rodent models and investigate its possible underlying mechanism. MATERIALS AND METHODS: Rats were orally administrated with 250, 500, and 1000 mg/kg body weight (bw) water extract of AM (WAM) for 28 and 35 consecutive days prior to the FST and UCMS protocols, respectively. The cerebral serotonin (5-HT) and the metabolites in the frontal cortex of rats were measured. The brain was dissected and the blood was collected to investigate the levels of inflammatory-related signaling pathway. RESULTS: All doses of WAM reduced the immobility time in the FST without disturbing autonomic locomotion. All doses of WAM prevented stress-induced abnormal behaviors in the UCMS model, including decreased sucrose preference and hypoactivity. 500 and 1000 mg/kg bw WAM attenuated the stress-induced increases in IL-1ß and TNF-α in the serum and cerebrum. 1000 mg/kg bw WAM alleviated brain inflammation by reducing the protein expression of ionized calcium binding adaptor molecule 1. CONCLUSION: WAM exhibited acute and chronic antidepressant-like effects, and may result from the anti-inflammatory actions. Therefore, the development of AM as a dietary therapy or adjuvant for depression treatment should be considered.


Assuntos
Anti-Inflamatórios/farmacologia , Antidepressivos/farmacologia , Armillaria/química , Depressão/tratamento farmacológico , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/isolamento & purificação , Antidepressivos/administração & dosagem , Antidepressivos/isolamento & purificação , Comportamento Animal/efeitos dos fármacos , Depressão/fisiopatologia , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Inflamação/tratamento farmacológico , Inflamação/patologia , Masculino , Ratos , Ratos Sprague-Dawley , Serotonina/metabolismo , Estresse Psicológico/tratamento farmacológico , Estresse Psicológico/fisiopatologia , Natação , Água
10.
Plant Cell Environ ; 44(1): 20-33, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32583877

RESUMO

Gastrodia elata, a fully mycoheterotrophic orchid without photosynthetic ability, only grows symbiotically with the fungus Armillaria. The mechanism of carbon distribution in this mycoheterotrophy is unknown. We detected high sucrose concentrations in all stages of Gastrodia tubers, suggesting sucrose may be the major sugar transported between fungus and orchid. Thick symplasm-isolated wall interfaces in colonized and adjacent large cells implied involvement of sucrose importers. Two sucrose transporter (SUT)-like genes, GeSUT4 and GeSUT3, were identified that were highly expressed in young Armillaria-colonized tubers. Yeast complementation and isotope tracer experiments confirmed that GeSUT4 functioned as a high-affinity sucrose-specific proton-dependent importer. Plasma-membrane/tonoplast localization of GeSUT4-GFP fusions and high RNA expression of GeSUT4 in symbiotic and large cells indicated that GeSUT4 likely functions in active sucrose transport for intercellular allocation and intracellular homeostasis. Transgenic Arabidopsis overexpressing GeSUT4 had larger leaves but were sensitive to excess sucrose and roots were colonized with fewer mutualistic Bacillus, supporting the role of GeSUT4 in regulating sugar allocation. This is not only the first documented carbon import system in a mycoheterotrophic interaction but also highlights the evolutionary importance of sucrose transporters for regulation of carbon flow in all types of plant-microbe interactions.


Assuntos
Gastrodia/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Proteínas de Plantas/metabolismo , Sacarose/metabolismo , Simbiose , Arabidopsis , Armillaria/metabolismo , Armillaria/fisiologia , Gastrodia/microbiologia , Gastrodia/fisiologia , Hibridização In Situ , Proteínas de Membrana Transportadoras/fisiologia , Microscopia Eletrônica de Transmissão , Micorrizas/metabolismo , Micorrizas/ultraestrutura , Proteínas de Plantas/fisiologia , Tubérculos/metabolismo , Tubérculos/microbiologia , Tubérculos/ultraestrutura , Plantas Geneticamente Modificadas
11.
J Appl Microbiol ; 131(1): 392-403, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33219581

RESUMO

AIMS: To isolate endophytic Trichoderma species and investigate the potential for biological control of the root rot pathogen Armillaria mellea. METHODS AND RESULTS: In all, 40 Trichoderma isolates were obtained from a range of host plants and identities were confirmed by ITS, rpb2 and tef1 sequence. When tested in dual culture assays for antagonism against A. mellea, Trichoderma isolates overgrew the A. mellea colonies within four days and by eight days 38 Trichoderma isolates significantly reduced A. mellea colony size. Armillaria mellea was unable to be recovered from five of eight co-cultivations tested, suggesting Trichoderma had killed the A. mellea in these cases. Pre-colonized hazel disks were used to determine what happens in a more heterogeneous situation with A. mellea and a refined set of eight Trichoderma isolates. Similar to plate-based assays, Trichoderma quickly covered A. mellea stopping any further growth and two Trichoderma isolates were able to eradicate A. mellea. CONCLUSIONS: Of the Trichoderma spp. tested, endophytic isolates of Trichoderma virens and T. hamatum offered the greatest antagonism towards A. mellea. Using pre-colonized hazel disks was of great importance for this work to demonstrate the fungal interactions in plant material. SIGNIFICANCE AND IMPACT OF THE STUDY: Controlling Armillaria root rot is difficult with chemical treatments, thus an environmentally benign and cost-effective alternative is required. This study highlights the prospect of biological control as an effective, environmentally friendly alternative to chemicals.


Assuntos
Antibiose , Armillaria/fisiologia , Corylus/microbiologia , Endófitos/fisiologia , Trichoderma/fisiologia , Endófitos/isolamento & purificação , Caules de Planta/microbiologia , Trichoderma/isolamento & purificação
12.
Appl Microbiol Biotechnol ; 105(1): 211-224, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33191459

RESUMO

Melleolides and armillyl orsellinates are protoilludene-type aryl esters that are synthesized exclusively by parasitic fungi of the globally distributed genus Armillaria (Agaricomycetes, Physalacriaceae). Several of these compounds show potent antimicrobial and cytotoxic activities, making them promising leads for the development of new antibiotics or drugs for the treatment of cancer. We recently cloned and characterized the Armillaria gallica gene Pro1 encoding protoilludene synthase, a sesquiterpene cyclase catalyzing the pathway-committing step to all protoilludene-type aryl esters. Fungal enzymes representing secondary metabolic pathways are sometimes encoded by gene clusters, so we hypothesized that the missing steps in the pathway to melleolides and armillyl orsellinates might be identified by cloning the genes surrounding Pro1. Here we report the isolation of an A. gallica gene cluster encoding protoilludene synthase and four cytochrome P450 monooxygenases. Heterologous expression and functional analysis resulted in the identification of protoilludene-8α-hydroxylase, which catalyzes the first committed step in the armillyl orsellinate pathway. This confirms that ∆-6-protoilludene is a precursor for the synthesis of both melleolides and armillyl orsellinates, but the two pathways already branch at the level of the first oxygenation step. Our results provide insight into the synthesis of these valuable natural products and pave the way for their production by metabolic engineering. KEY POINTS: • Protoilludene-type aryl esters are bioactive metabolites produced by Armillaria spp. • The pathway-committing step to these compounds is catalyzed by protoilludene synthase. • We characterized CYP-type enzymes in the cluster and identified novel intermediates.


Assuntos
Anti-Infecciosos , Armillaria , Sesquiterpenos , Armillaria/genética , Família Multigênica
13.
Nat Prod Res ; 35(6): 1042-1045, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31135223

RESUMO

Armillaria mellea, also known as Hazel mushroom, is a delicious food material and traditional herbal medicine in East Asia. Protoilludane sesquiterpenoid aromatic esters from A. mellea (PSAM) are the main active components with antibacterial and anticancer activities. This study explored the antidepressant-like activities of PSAM and its possible mechanisms of action using the open field test (OFT), tail suspension test (TST) and forced swimming test (FST) in mice for the first time. The results revealed that PSAM (1 mg/kg, i.p.) exhibited markedly antidepressant-like activity, which could be reversed by pretreatment with haloperidol (a non-selective D2 receptor antagonist), bicuculline (a competitive GABA antagonist), NMDA (an agonist at the glutamate site). Meanwhile, PSAM also effectively increased the hippocampus dopamine (DA) and γ-aminobutyric acid (GABA) and decreased the hippocampus glutamate (Glu) levels of mice, indicating that the antidepressant-like effect of PSAM might be mediated by the DAergic, GABAergic and Gluergic systems.


Assuntos
Antidepressivos/uso terapêutico , Armillaria/química , Ésteres/uso terapêutico , Sesquiterpenos Policíclicos/uso terapêutico , Sesquiterpenos/uso terapêutico , Animais , Antidepressivos/farmacologia , Comportamento Animal/efeitos dos fármacos , Depressão/tratamento farmacológico , Depressão/fisiopatologia , Dopamina/metabolismo , Fluoxetina/farmacologia , Fluoxetina/uso terapêutico , Ácido Glutâmico/metabolismo , Elevação dos Membros Posteriores , Masculino , Camundongos , Atividade Motora/efeitos dos fármacos , Teste de Campo Aberto , Sesquiterpenos Policíclicos/farmacologia , Reboxetina/farmacologia , Reboxetina/uso terapêutico , Natação , Ácido gama-Aminobutírico/metabolismo
14.
Sci Rep ; 10(1): 17625, 2020 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-33077756

RESUMO

Although cells of mushroom-producing fungi typically contain paired haploid nuclei (n + n), most Armillaria gallica vegetative cells are uninucleate. As vegetative nuclei are produced by fusions of paired haploid nuclei, they are thought to be diploid (2n). Here we report finding haploid vegetative nuclei in A. gallica at multiple sites in southeastern Massachusetts, USA. Sequencing multiple clones of a single-copy gene isolated from single hyphal filaments revealed nuclear heterogeneity both among and within hyphae. Cytoplasmic bridges connected hyphae in field-collected and cultured samples, and we propose nuclear migration through bridges maintains this nuclear heterogeneity. Growth studies demonstrate among- and within-hypha phenotypic variation for growth in response to gallic acid, a plant-produced antifungal compound. The existence of both genetic and phenotypic variation within vegetative hyphae suggests that fungal individuals have the potential to evolve within a single generation in response to environmental variation over time and space.


Assuntos
Armillaria/genética , Evolução Biológica , Hifas/genética , Esporos Fúngicos/genética , Núcleo Celular/genética , Citoplasma/genética , Diploide
15.
Food Funct ; 11(11): 9675-9685, 2020 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-33057558

RESUMO

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disorder characterized by hyperglycemia mainly due to insulin resistance. The objective of this study was to investigate the effects of polysaccharides from Armillariella tabescens mycelia (AT) on insulin resistance in mice fed a high-fat diet in combination with streptozotocin to induce T2DM. Following treatment with different doses of AT, hyperglycemia and lipid metabolism dysfunction, insulin resistance, and hepatic function-related indices were markedly ameliorated; the histopathological alterations, oxidative stress, and inflammatory reaction in hepatic tissue were also alleviated; most importantly, AT inhibited the expression of hepatic thioredoxin-interacting protein (TXNIP) to repress the nucleotide-binding oligomerization domain-like receptor protein 3 (NLRP3) inflammasome activation and activated the 5'AMP-activated protein kinase (AMPK) pathway in a dose-dependent manner in T2DM mice. In conclusion, these findings revealed that the hypoglycemic and hypolipidemic activities of AT were associated with the alleviation of insulin resistance through repression of the TXNIP/NLRP3 inflammasome pathway and activation of the AMPK pathway.


Assuntos
Armillaria , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/prevenção & controle , Alimento Funcional , Polissacarídeos/farmacologia , Animais , Diabetes Mellitus Tipo 2/induzido quimicamente , Diabetes Mellitus Tipo 2/prevenção & controle , Modelos Animais de Doenças , Resistência à Insulina , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estreptozocina
16.
BMC Genomics ; 21(Suppl 7): 534, 2020 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-32912216

RESUMO

BACKGROUND: Massive forest decline has been observed almost everywhere as a result of negative anthropogenic and climatic effects, which can interact with pests, fungi and other phytopathogens and aggravate their effects. Climatic changes can weaken trees and make fungi, such as Armillaria more destructive. Armillaria borealis (Marxm. & Korhonen) is a fungus from the Physalacriaceae family (Basidiomycota) widely distributed in Eurasia, including Siberia and the Far East. Species from this genus cause the root white rot disease that weakens and often kills woody plants. However, little is known about ecological behavior and genetics of A. borealis. According to field research data, A. borealis is less pathogenic than A. ostoyae, and its aggressive behavior is quite rare. Mainly A. borealis behaves as a secondary pathogen killing trees already weakened by other factors. However, changing environment might cause unpredictable effects in fungus behavior. RESULTS: The de novo genome assembly and annotation were performed for the A. borealis species for the first time and presented in this study. The A. borealis genome assembly contained ~ 68 Mbp and was comparable with ~ 60 and ~ 79.5 Mbp for the A. ostoyae and A. mellea genomes, respectively. The N50 for contigs equaled 50,544 bp. Functional annotation analysis revealed 21,969 protein coding genes and provided data for further comparative analysis. Repetitive sequences were also identified. The main focus for further study and comparative analysis will be on the enzymes and regulatory factors associated with pathogenicity. CONCLUSIONS: Pathogenic fungi such as Armillaria are currently one of the main problems in forest conservation. A comprehensive study of these species and their pathogenicity is of great importance and needs good genomic resources. The assembled genome of A. borealis presented in this study is of sufficiently good quality for further detailed comparative study on the composition of enzymes in other Armillaria species. There is also a fundamental problem with the identification and classification of species of the Armillaria genus, where the study of repetitive sequences in the genomes of basidiomycetes and their comparative analysis will help us identify more accurately taxonomy of these species and reveal their evolutionary relationships.


Assuntos
Armillaria , Basidiomycota , Armillaria/genética , Plantas , Sibéria
17.
Int J Med Mushrooms ; 22(5): 479-488, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32749102

RESUMO

Polyporus umbellatus is a traditional Chinese medicinal mushroom. The growth of P. umbellatus sclerotia requires the rhizomorphs of Armillaria spp. to supply nutrition. Whether the main components (MC) of sclerotia of P. umbellatus are related to the phylogeny of Armillaria associates or other environmental factors is largely unknown. In this study, we collected 17 sclerotia and soil samples from northeast to southwest China. In total, 17 Armillaria associates were isolated, and sclerotial MC contents and soil characteristics (total N, P, K, and organic matter) were determined. The analysis revealed that the MC content of P. umbellatus did not resemble a Brownian motion process in phylogeny of Armillaria associates, but were significantly influenced by the total N content of the soil. These results provide clear evidence that sclerotia of P. umbellatus associating with phylogenetic related Armillaria associates possess differing MC content. The mechanisms of nutrient exchange in P. umbellatus-Armillaria associations now require further elucidation.


Assuntos
Agaricales , Armillaria , Polyporus/metabolismo , Simbiose , Agaricales/genética , Agaricales/metabolismo , Armillaria/genética , Armillaria/metabolismo , China , Ergosterol/análise , Ergosterol/metabolismo , Genes Fúngicos , Filogenia , Polissacarídeos/análise , Polissacarídeos/metabolismo , Solo/química , Microbiologia do Solo
18.
Int J Biol Macromol ; 162: 1682-1691, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32758603

RESUMO

Diabetic kidney disease (DKD), accompanied by chronic low-grade inflammation, is one of the most common complications of diabetes. Armillariella tabescens has potent anti-inflammatory and immunomodulatory properties. The purpose of the present study was to investigate the effects of polysaccharides from Armillariella tabescens mycelia (AT) on the kidney in type 2 diabetic mice and explore the underlying mechanism. The mice were randomized into 4 groups: normal control (NC), diabetic control (DC), DC + 200 mg/kg AT (LAT), and DC + 400 mg/kg AT (HAT). The results showed that compared with the NC group, the levels of fasting blood glucose, renal function-related indices, and serum pro-inflammatory mediators including lipopolysaccharide (LPS), interleukin (IL)-1ß, and IL-18 were elevated; the renal morphopathological alterations, oxidative stress, and nucleotide-binding oligomerization domain-like receptor protein 3 inflammasome-mediated inflammation and renal fibrosis were aggravated; the intestinal microbiota dysbiosis and colonic inflammation and barrier dysfunction were deteriorated in the DC group. After supplementation with AT, the aforementioned indices were ameliorated in the AT treatment groups, especially in the HAT group. In conclusion, these results demonstrated that modulating the intestinal microbiota and inflammatory reaction was implicated in the effects of AT against DKD in mice.


Assuntos
Armillaria/química , Diabetes Mellitus Experimental/tratamento farmacológico , Nefropatias Diabéticas/tratamento farmacológico , Microbioma Gastrointestinal/efeitos dos fármacos , Rim/efeitos dos fármacos , Extratos Vegetais/uso terapêutico , Polissacarídeos/uso terapêutico , Animais , Anti-Inflamatórios/uso terapêutico , Fatores Imunológicos/uso terapêutico , Inflamação/tratamento farmacológico , Rim/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estresse Oxidativo/efeitos dos fármacos
19.
Braz J Microbiol ; 51(4): 1539-1552, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32572836

RESUMO

Armillaria species (Basidiomycota, Physalacriaceae) are well known as plant pathogens related to serious root rot disease on various trees in forests and plantations. Interestingly, some Armillaria species are essential symbionts of the rare Chinese medicinal herb Gastrodia elata, a rootless and leafless orchid used for over 2000 years. In this work, an 87.3-M draft genome of Armillaria gallica 012m strain, which was symbiotic with G. elata, was assembled. The genome includes approximately 23.6% repetitive sequences and encodes 26,261 predicted genes. In comparison with other four genomes of Armillaria, the following gene families related to pathogenicity/saprophytic phase, including cytochrome P450 monooxygenases, carbohydrate-active enzyme AA3, and hydrophobins, were significantly contracted in A. gallica 012m. These characteristics may be beneficial for G. elata to get less injuries. The genome-guided analysis of differential expression between rhizomorph (RH) and vegetative mycelium (VM) showed that a total of 2549 genes were differentially expressed, including 632 downregulated genes and 1917 upregulated genes. In the RH, most differentially expressed genes (DEGs) related to pathogenicity were significantly upregulated. To further elucidate gene function, Gene Ontology enrichment analysis showed that the upregulated DEGs significantly grouped into monooxygenase activity, hydrolase activity, glucosidase activity, extracellular region, fungal cell wall, response to xenobiotic stimulus, response to toxic substance, etc. These phenomena indicate that RH had better infection ability than VM. The infection ability of RH may be beneficial for G. elata to obtain nutrition, because the rhizomorph constantly infected the nutritional stems of G. elata and formed the hyphae that can be digested by G. elata. These results clarified the characteristics of A. gallica 012m and the reason why the strain 012m can establish a symbiotic relationship with G. elata in some extent from the perspective of genomics.


Assuntos
Armillaria , Gastrodia/microbiologia , Genoma Fúngico , Simbiose/genética , Armillaria/genética , Armillaria/fisiologia , China , Genômica , Filogenia
20.
BMC Microbiol ; 20(1): 108, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32370761

RESUMO

BACKGROUND: The ternary cropping system of Gastradia elata depends on a symbiotic relationship with the mycorrhizal fungi Armillaria mellea, which decays wood to assimilate nutrition for the growth of G. elata. The composition of microbe flora as key determinants of rhizoshere and mycorrhizoshere soil fertility and health was investigated to understand how G. elata and A. mellea impacted on its composition. The next generation pyrosequencing analysis was applied to assess the shift of structure of microbial community in rhizoshere of G. elata and mycorrhizoshere of A. mellea compared to the control sample under agriculture process. RESULTS: The root-associated microbe floras were significantly impacted by rhizocompartments (including rhizoshere and mycorrhizoshere) and agriculture process. Cropping process of G. elata enhanced the richness and diversity of the microbial community in rhizoshere and mycorrhizoshere soil. Furthermore, planting process of G. elata significantly reduced the abundance of phyla Basidiomycota, Firmicutes and Actinobacteria, while increased the abundance of phyla Ascomycota, Chloroflexi, Proteobacteria, Planctomycetes, and Gemmatimonadetes in rhizoshere and mycorrhizoshere. Besides, A. mellea and G. elata significantly enriched several members of saprophytoic and pathogenic fungus (i.e., Exophiala, Leptodontidium, Cosmospora, Cercophora, Metarhizium, Ilyonectria, and Sporothrix), which will enhance the possibility of G. elata disease incidence. At the same time, the ternary cropping system significantly deterred several members of beneficial ectomycorrhizal fungus (i.e., Russula, Sebacina, and Amanita), which will reduce the ability to protect G. elata from diseases. CONCLUSIONS: In the ternary cropping system of G. elata, A. mellea and G. elata lead to imbalance of microbial community in rhizoshere and mycorrhizoshere soil, suggested that further studies on maintaining the balance of microbial community in A. mellea mycorrhizosphere and G. elata rhizosphere soil under field conditions may provide a promising avenue for high yield and high quality G. elata.


Assuntos
Armillaria/crescimento & desenvolvimento , Bactérias/classificação , Fungos/citologia , Orchidaceae/crescimento & desenvolvimento , Análise de Sequência de DNA/métodos , Madeira/metabolismo , Agricultura , Armillaria/metabolismo , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Bactérias/isolamento & purificação , DNA Bacteriano/genética , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Fungos/genética , Fungos/crescimento & desenvolvimento , Fungos/isolamento & purificação , Sequenciamento de Nucleotídeos em Larga Escala , Micorrizas/crescimento & desenvolvimento , Orchidaceae/microbiologia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Rizosfera , Microbiologia do Solo
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