Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 65
Filtrar
Mais filtros










Intervalo de ano de publicação
1.
J Photochem Photobiol B ; 228: 112390, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35123160

RESUMO

The colorful agaricoid fruiting bodies of dermocyboid Cortinarii owe their magnificent hue to a mixture of anthraquinone (AQ) pigments. Recently, it was discovered that some of these fungal anthraquinones have an impressive photopharmacological effect. The question, therefore, arises as to whether these pigments are also of ecological or functional significance. According to the optimal defense hypothesis, toxic molecules should be enriched in spore-producing structures, such as the gills of agarics. To test this hypothesis, we studied the distribution of fungal AQs in the fruiting body of Cortinarius rubrophyllus. The fungus belongs to the well-studied Cortinarius subgenus Dermocybe but has not been chemically characterized. Here, we report on the pigment profile of this beautiful fungus and focus on the distribution of anthraquinone pigments in the fruiting body for the first time. Here it is statistically confirmed that the potent photosensitizer emodin is significantly enriched in the gills. Furthermore, we show that the extract is photoactive against cancer cells and bacteria.


Assuntos
Cortinarius , Emodina , Animais , Antraquinonas/química , Antraquinonas/farmacologia , Cortinarius/química , Emodina/farmacologia , Brânquias , Fármacos Fotossensibilizantes/farmacologia
2.
Sci Rep ; 12(1): 1108, 2022 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-35064132

RESUMO

Pigments of fungi are a fertile ground of inspiration: they spread across various chemical backbones, absorption ranges, and bioactivities. However, basidiomycetes with strikingly colored fruiting bodies have never been explored as agents for photodynamic therapy (PDT), even though known photoactive compound classes (e.g., anthraquinones or alkaloids) are used as chemotaxonomic markers. In this study, we tested the hypothesis that the dyes of skin-heads (dermocyboid Cortinarii) can produce singlet oxygen under irradiation and thus are natural photosensitizers. Three photosensitizers based on anthraquinone structures were isolated and photopharmaceutical tests were conducted. For one of the three, i.e., (-)-7,7'-biphyscion (1), a promising photoyield and photocytotoxicity of EC50 = 0.064 µM against cancer cells (A549) was found under blue light irradiation (λexc = 468 nm, 9.3 J/cm2). The results of molecular biological methods, e.g., a viability assay and a cell cycle analysis, demonstrated the harmlessness of 1 in the dark and highlighted the apoptosis-inducing PDT potential under blue light irradiation. These results demonstrate for the first time that pigments of dermocyboid Cortinarii possess a so far undescribed activity, i.e., photoactivity, with significant potential for the field of PDT. The dimeric anthraquinone (-)-7,7'-biphyscion (1) was identified as a promising natural photosensitizer.


Assuntos
Antraquinonas/isolamento & purificação , Cortinarius/química , Fármacos Fotossensibilizantes/isolamento & purificação , Células A549 , Antraquinonas/farmacologia , Cortinarius/metabolismo , Cortinarius/efeitos da radiação , Células HeLa , Humanos , Luz , Fármacos Fotossensibilizantes/farmacologia , Oxigênio Singlete/metabolismo
3.
J Agric Food Chem ; 70(3): 804-814, 2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35029386

RESUMO

Two new polyketides named rufoolivacin E and viocristin B, a new natural product named 1-hydroxy-3,6,8-trimethoxyanthraquinone, and 13 known compounds were isolated from edible mushroom Cortinarius purpurascens in this work. Their structures were assigned on the basis of high-resolution electrospray ionization mass spectrometry, 1D and 2D nuclear magnetic resonance, and electronic circular dichroism data. Notably, the enzyme activity test on glutamate dehydrogenase indicated that 1, 3, 4, 5, 6, 10, 11, and 15 displayed an excellent inhibition effect. Further kinetic studies showed that the most potent compounds, 4 and 10, possess great potential as competitive inhibitors of glutamate dehydrogenase. Molecular docking and computational chemistry were applied to illustrate the binding mechanism in detail. 2,2-Diphenyl-1-picrylhydrazyl and reactive oxygen species assay results showed that compounds 1, 2, 3, and 8 exhibited significant antioxidant activities with IC50 values of 7.0 ± 0.3, 8.6 ± 0.1, 7.5 ± 0.1, and 2.8 ± 0.2 µg mL-1, respectively. Thus, Cortinarius caerulescens represents a novel resource of these polyketides to be utilized in food selection and drug discovery.


Assuntos
Agaricales , Policetídeos , Antioxidantes/farmacologia , Cortinarius , Glutamato Desidrogenase , Cinética , Simulação de Acoplamento Molecular , Estrutura Molecular , Policetídeos/farmacologia , Polímeros
4.
Photochem Photobiol Sci ; 21(2): 221-234, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34971447

RESUMO

Mushrooms such as the dermocyboid Cortinarius rubrophyllus are characterized by strikingly colorful fruiting bodies. The molecular dyes responsible for such colors recently experienced a comeback as photoactive compounds with remarkable photophysical and photobiological properties. One of them-7,7'-biphyscion-is a dimeric anthraquinone that showed promising anticancer effects in the low nanomolar range under blue-light irradiation. Compared to acidic anthraquinones, 7,7'-biphyscion was more efficiently taken up by cells and induced apoptosis after photoactivation. However, seasonal collection of mushrooms producing this compound, low extraction yields, and tricky fungal identification hamper further developments to the clinics. To bypass these limitations, we demonstrate here an alternative approach utilizing a precursor of 7,7'-biphyscion, i.e., the pre-anthraquinone flavomannin-6,6'-dimethyl ether, which is abundant in many species of the subgenus Dermocybe. Controlled oxidation of the crude extract significantly increased the yield of 7,7'-biphyscion by 100%, which eased the isolation process. We also present the mycochemical and photobiological characterization of the yet chemically undescribed species, i.e. C. rubrophyllus. In total, eight pigments (1-8) were isolated, including two new glycosylated anthraquinones (1 and 2). Light-dependent generation of singlet oxygen was detected for the first time for emodin-1-O-ß-D-glucopyranoside (3) [photophysical measurement: Φ∆ = 0.11 (CD3OD)]. Furthermore, emodin (7) was characterized as promising compound in the photocytotoxicity assay with EC50-values in the low micromolar range under irradiation against cells of the cancer cell lines AGS, A549, and T24.


Assuntos
Cortinarius , Fármacos Fotossensibilizantes , Antraquinonas/química , Antraquinonas/farmacologia , Cortinarius/química , Fármacos Fotossensibilizantes/farmacologia
5.
Mycologia ; 113(5): 1022-1055, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34236939

RESUMO

In the Patagonian region, Cortinarius is the most diverse and abundant genus of ectomycorrhizal fungi with at least 250 species. Sequestrate forms were until recently documented within the genus Thaxterogaster, a genus now known to be polyphyletic, and many were consequently transferred to Cortinarius. Original descriptions were mostly available in German and Spanish and interpretations of morphological structures outdated. Despite recent advances in Cortinarius systematics, the current classification, diversity, and ecology of sequestrate "cortinarioid" fungi in Patagonia remain unclear. The objective of this study was to provide an update on sequestrate Cortinarius of southern South America. We documented each species with morphological descriptions, photographs, basidiospore scanning electron microscopy (SEM) images, and molecular characterization using nuc rDNA internal transcribed spacer region ITS1-5.8S-ITS2 (ITS) and nuc 28S rDNA (28S) sequence data. Original descriptions of taxa were also translated to English and revised based on fresh collections. We documented 24 species from Patagonia based on molecular data and conducted morphological and phylogenetic analysis for 18 previously described species based on type and reference specimens. In addition, we formally described two new species. Four additional taxa were provisionally determined as new but require further study. New ITS sequence data were produced from eight type specimens. We also provide a new name, Cortinarius gloiodes, nom. nov., for the taxon previously described as Thaxterogaster gliocyclus. In addition to the species treated in detail, we provided additional reference information and discussion on six described species that remained incompletely known or for which no recent collections were found. Of the 24 taxa documented from Patagonia, 15 species were assigned to 12 current sections in the genus Cortinarius. Analysis of spore ultrastructure showed that sequestrate forms of Patagonian Cortinarius lack a true perisporium.


Assuntos
Agaricales , Cortinarius , Agaricales/genética , Cortinarius/genética , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Filogenia , Análise de Sequência de DNA
6.
J Environ Qual ; 50(4): 877-888, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34048608

RESUMO

Levels of environmental mercury (Hg) within the Canadian Arctic are a current area of concern. Although efforts have been made to reduce Hg released into the environment, levels remain elevated in flora and fauna. This study examined the concentrations of Hg in soil and naturally occurring edible plant and fungi species, identified by local Inuit residents, from eight locations in Iqaluit, Nunavut, and the surrounding area during the summers of 2018 and 2019. Total Hg concentrations were obtained in 24 soil samples, 112 flora samples from 23 plant and five lichen species, and 157 fungal samples from eight species. Median Hg concentrations in plant species ranged from 0.005 µg g-1 Hg dry weight (dw) in Saxifraga cernua to 0.19 µg g-1 Hg dw in Oxytropis maydelliana. Median concentrations in edible fungi species ranged from 0.084 µg g-1 Hg dw in the Cortinarius croceus (non-puffball species) to 1.6 µg g-1 Hg dw in Lycoperdon perlatum (a puffball mushroom). Additionally, median Hg concentration in puffball species (1.4 µg g-1 ) were higher than non-puffball species (0.12 µg g-1 ). Three puffball species were assessed for methylmercury (MeHg), with mean concentrations ranging from 0.013 to 0.085 µg g-1 MeHg dw. Limited research has been conducted on Hg uptake in naturally occurring edible plant and fungi species of the Canadian Arctic. This study contributes important information on Hg accumulation and processes in edible plant and fungi Arctic species, is the first to focus on plants used by the local Indigenous community, and demonstrates a need for further studies to assess Hg in Arctic environments.


Assuntos
Mercúrio , Agaricales , Regiões Árticas , Canadá , Cortinarius , Monitoramento Ambiental , Fungos , Mercúrio/análise , Plantas Comestíveis
7.
Ecol Lett ; 24(7): 1341-1351, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33934481

RESUMO

Boreal forest soils are important global carbon sinks, with significant storage in the organic topsoil. Decomposition of these stocks requires oxidative enzymes, uniquely produced by fungi. Across Swedish boreal forests, we found that local carbon storage in the organic topsoil was 33% lower in the presence of a group of closely related species of ectomycorrhizal fungi - Cortinarius acutus s.l.. This observation challenges the prevailing view that ectomycorrhizal fungi generally act to increase carbon storage in soils but supports the idea that certain ectomycorrhizal fungi can complement free-living decomposers, maintaining organic matter turnover, nutrient cycling and tree productivity under nutrient-poor conditions. The indication that a narrow group of fungi may exert a major influence on carbon cycling questions the prevailing dogma of functional redundancy among microbial decomposers. Cortinarius acutus s.l. responds negatively to stand-replacing disturbance, and associated population declines are likely to increase soil carbon sequestration while impeding long-term nutrient cycling.


Assuntos
Micorrizas , Taiga , Carbono , Sequestro de Carbono , Cortinarius , Florestas , Fungos , Solo , Microbiologia do Solo , Suécia
8.
Mycologia ; 112(3): 588-605, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32315246

RESUMO

CORTINARIUS: is a species-rich ectomycorrhizal genus containing taxa that exhibit agaricoid or sequestrate basidiome morphologies. In New Zealand, one of the most recognizable and common Cortinarius species is the purple sequestrate fungus, C. porphyroideus. We used genome skimming of the almost 100-y-old type specimen from C. porphyroideus to obtain the nuc rDNA internal transcribed spacer region ITS1-5.8S-ITS2 (ITS barcode) and partial nuc rDNA 28S (28S) sequences. The phylogenetic position of C. porphyroideus was established, and we found that it represents a rarely collected species. Purple sequestrate Cortinarius comprise multiple cryptic species in several lineages. We describe four new species of Cortinarius with strong morphological similarity to C. porphyroideus: Cortinarius diaphorus, C. minorisporus, C. purpureocapitatus, and C. violaceocystidiatus. Based on molecular evidence, Thaxterogaster viola is recognized as Cortinarius violaceovolvatus var. viola. These species are associated with Nothofagus (southern beech) and have very similar morphology to C. porphyroideus but are all phylogenetically distinct based on molecular data.


Assuntos
Cor , Cortinarius/classificação , Cortinarius/genética , DNA Fúngico/genética , Micorrizas/genética , Filogenia , RNA Ribossômico 28S , DNA Espaçador Ribossômico , Nova Zelândia , Análise de Sequência de DNA
9.
Chembiochem ; 21(10): 1423-1427, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32159919

RESUMO

Dimeric polyketides are widespread fungal secondary metabolites. They occur in both ascomycetes and basidiomycetes and, therefore, across fungal phyla. Here we report the isolation of a new binaphthalene, named rufoschweinitzin, from the basidiomycete Cortinarius rufoolivaceus. Rufoschweinitzin consists of two symmetrically 4,4'-coupled torachrysone-8-O-methyl ether moieties. Furthermore, we have identified a binaphthalene biosynthetic gene cluster in an unrelated fungus, the ascomycete Xylaria schweinitzii. Heterologous expression of the encoded cytochrome P450 enzyme verified its coupling activity: dimerization of torachrysone-8-O-methyl ether led to the formation of rufoschweinitzin alongside a hitherto unknown regioisomer, now named alloschweinitzin. We have thus demonstrated enzymatic formation of the basidiomycete's metabolite rufoschweinitzin and made the regiochemistry of alloschweinitzin accessible with an ascomycete-derived enzyme.


Assuntos
Ascomicetos/metabolismo , Cortinarius/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Proteínas Fúngicas/metabolismo , Naftalenos/metabolismo , Naftóis/metabolismo , Policetídeos/metabolismo , Ascomicetos/crescimento & desenvolvimento , Cortinarius/crescimento & desenvolvimento , Estereoisomerismo
10.
Environ Pollut ; 255(Pt 1): 113208, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31654855

RESUMO

Cortinarius caperatus grows in the northern regions of Europe, North America and Asia and is widely collected by mushroom foragers across Europe. This study shows that in the last three decades since the Chernobyl nuclear accident, C. caperatus collected across much of Northern Poland exhibited high activity concentrations of radiocaesium (137Cs) - a long-lived radionuclide. The mushroom appears to efficiently bioconcentrate 137Cs from contaminated soil substrata followed by sequestration into its morphological parts such as the cap and stipe which are used as food. The gradual leaching of 137Cs into the lower strata of surface soils in exposed areas are likely to facilitate higher bioavailability to the mycelia of this species which penetrate to relatively greater depths and may account for the continuing high activity levels noticed in Polish samples (e.g. activity within caps in some locations was still at 11,000 Bq kg-1 dw in 2008 relative to a peak of 18,000 in 2002). The associated dietary intake levels of 137Cs have often exceeded the tolerance limits set by the European Union (370 and 600 Bq kg-1 ww for children and adults respectively) during the years 1996-2010. Human dietary exposure to 137Cs is influenced by the method of food preparation and may be mitigated by blanching followed by disposal of the water, rather than direct consumption after stir-frying or stewing. It may be prudent to provide precautionary advice and monitor activity levels, as this mushroom continues to be foraged by casual as well as experienced mushroom hunters.


Assuntos
Bioacumulação , Radioisótopos de Césio/análise , Cortinarius/química , Contaminação Radioativa de Alimentos/análise , Radioisótopos de Potássio/análise , Ásia , Acidente Nuclear de Chernobyl , Europa (Continente) , Humanos , Micélio/química , América do Norte , Polônia , Solo/química
11.
Phytochemistry ; 165: 112048, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31229789

RESUMO

For the first time, the pigment composition of basidiocarps from the Chilean mushroom Cortinarius pyromyxa was studied under various aspects like phylogeny, chemistry and antibiotic activity. A molecular biological study supports the monotypic position of C. pyromyxa in subgenus Myxacium, genus Cortinarius. Four undescribed diterpenoids, named pyromyxones A-D, were isolated from fruiting bodies of C. pyromyxa. Their chemical structures were elucidated based on comprehensive one- and two-dimensional NMR spectroscopic analysis, ESI-HRMS measurements, as well as X-ray crystallography. In addition, the absolute configurations of pyromyxones A-D were established with the aid of JH,H, NOESY spectra and quantum chemical CD calculation. The pyromyxones A-D possess the undescribed nor-guanacastane skeleton. Tested pyromyxones A, B, and D exhibit only weak activity against gram-positive Bacillus subtilis and gram-negative Aliivibrio fischeri as well as the phytopathogenic fungi Botrytis cinerea, Septoria tritici and Phytophthora infestans.


Assuntos
Antibacterianos/farmacologia , Cortinarius/química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Pigmentos Biológicos/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Cristalografia por Raios X , Diterpenos/química , Diterpenos/isolamento & purificação , Diterpenos/farmacologia , Testes de Sensibilidade Microbiana , Modelos Moleculares , Estrutura Molecular , Filogenia , Pigmentos Biológicos/química , Pigmentos Biológicos/isolamento & purificação , Teoria Quântica
12.
Acta bioquím. clín. latinoam ; 53(1): 79-107, mar. 2019. ilus
Artigo em Espanhol | LILACS | ID: biblio-1001081

RESUMO

En este trabajo se analizan los micetismos menos comunes, caracterizados por la aparición demorada de síntomas y por tiempos de latencia muy largos. Estas intoxicaciones son provocadas por especies de hongos ectomicorrícicos poco comunes. Se analizan: a) Toxíndrome nefrotóxico demorado o retrasado. Micetismo orellánico o por orellanina. b) Toxíndrome con rabdomiólisis. Micetismos por Tricholoma equestre y Tricholoma terreum. c) Toxíndrome encefalopático o neurotóxico retrasado. Micetismo por Pleurocybella porrigens. d) Toxíndrome cardiovascular. Micetismo por Trogia venenata. Se discuten el tiempo de incubación, las características sintomatológicas, el curso clínico, las toxinas responsables de cada micetismo y su mecanismo de acción, y el tratamiento que ha resultado efectivo para la recuperación de los pacientes.


Less common mycetisms, characterized by delayed-onset and very long latency times are analyzed. These intoxications are caused by rare ectomycorrhizal fungal species. The following syndromes have been taken into account: (a) Delayed nephrotoxic syndrome. Orellanic mycetism or mycetism due to orellanin. (b) Syndrome with rhabdomyolysis. Mycetisms by Tricholoma equestre, and Tricholoma terreum. (c) Delayed encephalopathic or neurotoxic syndrome. Mycetism by Pleurocybella porrigens. (d) Cardiovascular syndrome. Mycetism by Trogia venenata. The incubation time, symptom characteristics, clinical course, toxins responsible for each mycetism and their mechanism of action, and treatment that has shown to be effective for patient recovery are discussed.


Neste trabalho, analisam-se micetismos menos comuns, caracterizados pelo aparecimento retardado de sintomas e tempos de latência muito longos. Essas intoxicações são causadas por espécies raras de fungos ectomicorrízicos. São analisados os seguintes: (a) síndrome de toxicidade nefrotóxica retardada ou atrasada. Micetismo orelânico ou micetismo por orelanina. (b) Toxíndrome com rabdomiólise. Micetismo por Tricholoma equestre e Tricholoma terreum. (c) Toxicidade tardia encefalopática ou neurotóxica. Micetismo por Pleurocybella porrigens. (d) Síndrome cardiovascular. Miceticismo por Trogia venenata. O tempo de incubação, as características sintomatológicas, o curso clínico, as toxinas responsáveis por cada micetismo e seu mecanismo de ação e o tratamento efetivo para a recuperação dos pacientes são discutidos.


Assuntos
Humanos , Síndrome , Cortinarius , Tricholoma , Pacientes , Envenenamento , Rabdomiólise , Sinais e Sintomas , Toxicologia , Toxicidade , Fungos
13.
Mycologia ; 111(1): 103-117, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30676893

RESUMO

Because of systematic sampling campaigns in the northern Patagonian Nothofagaceae forests of Argentina, several specimens of sequestrate fungi were collected. Some of those collections showed phylogenetic affinities and morphological similarities to members of the formerly recognized sequestrate genus Thaxterogaster, currently a synonym of Cortinarius on the basis of molecular data. Comparisons of macro- and micromorphological features and sequences of nuc rDNA internal transcribed spacer (ITS) regions have revealed that these collections belong to formerly undescribed species. The sequences of the four new taxa presented here, Cortinarius flavopurpureus, C. translucidus, C. nahuelhuapensis, and C. infrequens, were combined into a data set including additional sequences generated from herbarium collections and retrieved from public gene databases and analyzed by maximum likelihood and Bayesian inference methods. The four new species were resolved as distinct clades with strong support; at the same time, they showed unique morphological characteristics (hypogeous to subhypogeous habit, complete gasteromycetation, and spore shape and ornamentation) that separate them from previously described Cortinarius species. In addition, several undescribed and/or not previously sequenced species from these forests were detected through phylogenetic analysis of ectomycorrhizal root tip sequences. A key of characters to identify the sequestrate Cortinarius from Patagonia is provided.


Assuntos
Cortinarius/classificação , Cortinarius/genética , DNA Fúngico/genética , Argentina , Teorema de Bayes , Cortinarius/isolamento & purificação , DNA Espaçador Ribossômico/genética , Florestas , Filogenia , Análise de Sequência de DNA
14.
Mycologia ; 110(6): 1127-1144, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30489223

RESUMO

In this study, we document and describe the new Cortinarius section Austroamericani. Our results reveal high species diversity within this clade, with a total of 12 recognized species. Of these, only C. rufus was previously documented. Seven species are described as new based on basidiomata collections. The four remaining species are only known from environmental sequences. All examined species form ectomycorrhizal associations with species of Nothofagaceae and are currently only known from Argentinean and Chilean Patagonia. The phylogenetic analysis based on the nuc rDNA internal transcriber spacer (ITS1-5.8S-ITS2 = ITS) and partial 28S gene (28S) sequences shows that this section is related to other taxa from the Southern Hemisphere. Species in this group do not belong to subg. Telamonia, where C. rufus was initially placed. Cortinarius rufus and the newly described C. subrufus form a basal clade within sect. Austroamericani that has a weakly supported relationship with the core clade. Because the two species are morphologically similar to species from the core clade and share their distribution and Nothofagaceae associations, we include them here as part of sect. Austroamericani sensu lato (s.l.) until more material is available to refine the delimitation.


Assuntos
Cortinarius/classificação , Florestas , Filogenia , Chile , Cortinarius/isolamento & purificação , Código de Barras de DNA Taxonômico , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Fagales , Variação Genética , Técnicas de Tipagem Micológica , Análise de Sequência de DNA , Especificidade da Espécie
15.
Fungal Biol ; 122(11): 1077-1097, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30342624

RESUMO

Cortinarius magellanicus Speg. is an edible, ectomycorrhizal fungus, widely distributed in Argentina, Chile and New Zealand. However, earlier studies already indicated that the epithet 'magellanicus' might have been applied in a wide sense, thus circumscribing several species. A neotype was designated by Moser and Horak (1975) due Spegazzini's type was lost. Argentinian Nothofagaceae forests' samples, from autumn of 2017, morphologically recognized as C. magellanicus were used for a phylogenetic analysis, including sequences from type material and closely related species. Our results showed that C. magellanicus represents a complex of species, with at least three phylogenetic lineages, each with strong regionalism and distinct host associations. Cortinarius magellanicus s. str. is restricted to Patagonia of Argentina and Chile. The misidentified reports from New Zealand and Australia represent distinct and different lineages. In the present contribution, the re-description of C. magellanicus is based on neotype material and two new species are proposed. Cortinarius vitreopileatus var. similissimus is described as variety from New Zealand resembling C. magellanicus, however without close phylogenetic relationship to it. The taxonomic delimitation for C. magellanicus species complex is of high relevance due to the abundance of these fungi and their ectomycorrhizal role in Nothofagaceae forests in Gondwanian region.


Assuntos
Cortinarius/isolamento & purificação , Magnoliopsida/microbiologia , Micorrizas/isolamento & purificação , Argentina , Austrália , Chile , Cortinarius/classificação , Cortinarius/genética , Cortinarius/crescimento & desenvolvimento , Ecossistema , Florestas , Micorrizas/classificação , Micorrizas/genética , Micorrizas/crescimento & desenvolvimento , Nova Zelândia , Filogenia , Esporos Fúngicos/classificação , Esporos Fúngicos/genética , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/isolamento & purificação
16.
Bol. micol. (Valparaiso En linea) ; 33(1): 9-20, jun. 2018. tab
Artigo em Inglês | LILACS | ID: biblio-904961

RESUMO

Chilean temperate rainforests have unique climatic, edaphic and biotic conditions, constituting pre-industrial blueprint ecosystems. Mycorrhizal associations play a central role in the biogeochemical processes of these ecosystems´ functioning. Baseline forest ecology studies are necessary in order to better understand diversity patterns, specifically regarding mycorrhizal symbiosis. Therefore, here we describe the vegetation characteristics and the mycorrhizal relationships of vascular plants in a Nothofagus pumilio forest. We also describe, via morphological methods, the ectomycorrhizal diversity present in this forest. Additionally, we determined whether ectomycorrhizal inoculation confers positive growth effects on N. pumilio seedlings. We found that from 46 vascular plant species identified in this study, 42 (91%) were mycorrhizal and of these 33 (72%) were associated with arbuscular mycorrhizae (AM), two (the dominant trees N. pumilio and N. dombeyi) were forming ectomycorrhizae (EM), five were associated with ericoid mycorrhizae, two with orchid mycorrhizae, and four were nonmycorrhizal. Additionally, 26 EM species were detected of which 15 belong to Cortinarius. Finally, there were clear differences in the growth of N. pumilio seedlings inoculated with the ectomycorrhizal fungus Laccaria laccata compared to noninoculated plants. We suggest that mycorrhizal fungi play a key role in seedling colonization of harsh environments such as the Andean treeline.


Los bosques templados lluviosos de Chile tienen condiciones climáticas, edáficas y bióticas únicas, constituyendo ecosistemas preindustriales modelo. Las asociaciones micorrízicas juegan un rol central en los procesos biogeoquímicos del funcionamiento de estos ecosistemas. Por lo tanto, en este estudio describimos las características de la vegetación y las relaciones micorrízicas de las plantas vasculares de un bosque de Nothofagus pumilio. También describimos, vía métodos morfológicos, la diversidad ectomicorrízica presente en este bosque. Adicionalmente, determinamos si inoculaciones ectomicorrízicas confieren efectos de crecimiento positivos a semilleros de N. pumilio. Encontramos que, de 46 especies de plantas vasculares identificadas en este estudio, 42 (91%) son micorrízicas, y de estas, 33 (72%) están formando micorrizas arbusculares (AM), dos (los árboles dominantes N. pumilio y N. dombeyi) están asociados con ectomicorrizas (EM), cinco están asociadas con micorrizas ericoides, dos con micorrizas orquioides, y cuatro fueron nomicorrizadas. Adicionalmente, 26 especies de EM fueron detectadas, de las cuales 15 pertenecen a Cortinarius. Finalmente, hubo claras diferencias en el crecimiento de los semilleros de N. pumilio inoculados con el hongo ectomicorrízico Laccaria laccata, comparados a plantas no inoculadas. Sugerimos que los hongos micorrízicos juegan un rol clave en la colonización de ambientes severos por juveniles, como en el límite altitudinal andino.


Assuntos
Micorrizas/citologia , Micorrizas/crescimento & desenvolvimento , Floresta Úmida , Chile , Cortinarius , Simbiose , Clima Temperado
17.
Fungal Biol ; 121(10): 876-889, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28889912

RESUMO

The descolea clade includes species of ectomycorrhizal basidiomycetes in the genera Descolea, Setchelliogaster, Descomyces, and Timgrovea that are known primarily from the Southern Hemisphere. Taxa in this group produce basidiomes that range in morphology from typical epigeous mushrooms (Descolea) and secotioid taxa (Setchelliogaster) to fully gasteroid species (Descomyces and Timgrovea). High intraspecific morphological variation has been reported in several species within this clade, suggesting that careful morphological and molecular studies are needed to refine species concepts. Molecular analyses of fresh Patagonian collections in conjunction with taxonomic studies have confirmed high variability in key morphological features, including overall sporocarp form, spore shape and dimensions, universal veil remnants, and cuticle configuration. Based on our synthesis, we emend the genus Descolea to include sequestrate species. We describe the new sequestrate taxon Descolea inferna sp. nov. from Nothofagaceae forests in Patagonia and we propose Cortinarius squamatus as a synonym of our new combination Descolea brunnea. We also formalize the identity of Descolea pallida as a synonym of Descolea antarctica and provide new specimens of Cortinarius archeuretus, a species that has not been encountered since the original discovery during the expeditions of Roland Thaxter in 1905-1906. Here we re-describe and transfer this species to Descolea as D. archeureta. We also discuss diagnostic features that can be used to delimitate the four known South American taxa in the descolea clade.


Assuntos
Agaricales/classificação , Fagales/microbiologia , Agaricales/genética , Agaricales/crescimento & desenvolvimento , Argentina , Cortinarius/classificação , Cortinarius/genética , Cortinarius/crescimento & desenvolvimento , DNA Fúngico/química , DNA Fúngico/isolamento & purificação , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/isolamento & purificação , Filogenia , Alinhamento de Sequência
18.
Mycologia ; 109(3): 443-458, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28762885

RESUMO

Seven species of Cortinarius, subgenus Telamonia, section Colymbadini and /Flavobasilis, are reported from conifer forests in the mountains of western North America. They typically produce basidiomes in the spring and summer. Only one species, C. colymbadinus, is widespread, occurring in Europe and western North America, but to date not reported from California. Cortinarius bridgei, C. flavobasilis, C. rumoribrunsi, C. vernalishastensis, and C. vernalisierraensis are new species. The first two are found throughout the western mountains, whereas the latter three thus far are known only from California. Cortinarius ahsii, a common species in the Rocky Mountains and Pacific Northwest, also has not been recorded from California.


Assuntos
Cortinarius/classificação , Cortinarius/isolamento & purificação , Análise por Conglomerados , Cortinarius/citologia , Cortinarius/genética , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Florestas , Microscopia , Noroeste dos Estados Unidos , Filogenia , Análise de Sequência de DNA , Traqueófitas/microbiologia
19.
BMC Nephrol ; 18(1): 121, 2017 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-28372584

RESUMO

BACKGROUND: Accidental intake of mushrooms of the Cortinarius species (deadly webcap) may cause irreversible renal damage and the need for dialysis or transplantation. The species is found in forests of Northern Europe, Scandinavia and North America and may be mistaken for other edible mushrooms. The highly selective nephrotoxic compound of the mushroom is called orellanine. Very little is known about the long-term effects of the nephrotoxin. METHODS: We identified patients who ingested deadly webcap in the period of 1979 to 2012. Informed consent and medical records were obtained for 28 of the 39 cases that occurred during the 34-year period. A case control group was also studied based on sex, age and initiation of dialysis or transplantation. RESULTS: The average age at time of the accidental intake was 40 ± 3 (n = 28) years. 64% of patients were male, and 22 of 28 patients developed acute kidney injury requiring dialysis. Serum creatinine peaked at 1 329 ± 133 µmol/l, and serum urea was 31 ± 3.5 mmol/l. No signs of acute damage were present in any other organ. The average time of follow-up was 16.9 ± 2.1 years (1.24-34.3 years, n = 28). 15 patients were transplanted and 3 also had a second graft. At follow-up, 23 patients were alive, and five had died at ages of 67 ± 5 (range 54-84). The outcome was similar in the case control group with 6 deaths in 20 patients. CONCLUSION: We conclude that the long-term prognosis for patients poisoned by deadly webcap who lost their renal function is not different compared to other patients in active uremic care.


Assuntos
2,2'-Dipiridil/análogos & derivados , Injúria Renal Aguda/induzido quimicamente , Transplante de Rim , Micotoxinas/envenenamento , Diálise Renal , 2,2'-Dipiridil/envenenamento , Injúria Renal Aguda/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Casos e Controles , Cortinarius , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Mortalidade , Prognóstico , Estudos Retrospectivos , Adulto Jovem
20.
Nat Prod Res ; 31(4): 473-476, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27198920

RESUMO

From the fruiting body of ectomycorrhizal fungi Cortinarius xiphidipus, sterols were identified from the crude extract and the cytotoxic effect of ergosta-4, 6, 8(14), 22-tetraen-3-one (ergone) was evaluated. Ten sterols including ergosta-3,5,7,9(11),22-pentaene, (22E)-ergosta-5,7,9(11),22-tetraen-3b-ol, (3ß,22E)-ergosta-5,7,22-trien-3-ol, (22E)-ergosta-7,22-dien-3-ol, neoergosterol, (3ß)-ergosta-5,8-dien-3-ol, (3ß)-ergosta-7-en-3-ol, stigmasterol, stigmasterol 22,23-dihydro and (22E)-ergosta-4,6,8(14),22-tetraen-3-one were identified from the crude extract. The cytotoxic activity of the sterol fraction containing ergosta-4, 6, 8(14), 22-tetraen-3-one was assessed on four tumour cell lines (Neuro-2a, Saos-2, MCF7 and LNCaP-C42). The cytotoxic activity against the four tumour cell lines tested, being Neuro-2a and Saos-2 the most sensitive, with a half-maximal inhibitory concentration (IC50) of 20.8 ± 2.2 and 27.8 ± 1.0 µg/mL, respectively. This is the first report of this Antarctic fungi collected in the Magallanes and Chilean Antarctica Region. This work represents a potential source for the development of anticancer drugs.


Assuntos
Antineoplásicos/farmacologia , Cortinarius/química , Esteróis/análise , Linhagem Celular Tumoral , Ergosterol/análogos & derivados , Ergosterol/análise , Humanos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...