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1.
J Basic Microbiol ; 58(12): 1043-1052, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30183105

RESUMO

A novel acidic α-galactosidase (EC 3.2.1.22) designated as Leucopaxillus tricolor α-galactosidase (LTG) has been purified to homogeneity from the fruiting bodies of L. tricolor to 855-fold with a specific activity of 956 U mg-1 by the application of chromatography and gel filtration. The molecular mass of LTG was estimated to be 60 kDa as determined by both SDS-PAGE and by gel filtration. The purified enzyme was identified by LC-MS/MS and four inner amino acid sequences were obtained. When 4-nitrophenyl α-D-glucopyranoside (pNPGal) was used as substrate, the optimal pH and optimal temperature of LTG were pH 5.0 and 50 °C, respectively. The enzyme activity was strongly inhibited by Hg2+ , Fe3 , Cu2+ , Cd2+ , and Mn2+ ions. The chemical modification agent N-bromosuccinimide (NBS) completely inhibited the enzyme activity of LTG, indicating the paramount importance of tryptophan residue(s) to its enzymatic activity. Besides, LTG displayed wide substrate diversity with activity toward a variety of substrates such as stachyose, raffinose, melibiose, locust bean gum, and guar gum. Given the good ability of degrading the non-digestible and flatulence-causing oligosaccharides, this fungus may become a useful source of α-galactosidase for multiple applications.


Assuntos
Agaricales , Carpóforos/enzimologia , Oligossacarídeos/metabolismo , alfa-Galactosidase/metabolismo , Agaricales/citologia , Bromosuccinimida , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Metais Pesados , Peso Molecular , Especificidade por Substrato , Temperatura , alfa-Galactosidase/antagonistas & inibidores , alfa-Galactosidase/isolamento & purificação
2.
Mycologia ; 110(3): 605-617, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29993332

RESUMO

Hymenogaster is an ectomycorrhizal genus of brown-spored sequestrate fungi that is related to the mushroom-forming genera Hebeloma and Alnicola (Agaricales). However, because of difficulties in morphological taxonomy of sequestrate fungi, Hymenogaster has become a polyphyletic repository for a variety of unrelated brown-spored sequestrate species. During studies of ectomycorrhizal ecology and sequestrate fungal evolution in the western USA, we encountered specimens of a morphologically unique species. It was originally described as Hymenogaster macmurphyi, but our morphological and molecular analyses indicate that it is not closely related to Hymenogaster. Phylogenetic analyses of multiple gene regions indicate that H. macmurphyi is actually a member of the Boletineae (Boletales, Basidiomycota) and is nested within the epigeous genus Xerocomellus, distantly related to any of the other known genera of sequestrate Boletales. While examining additional herbarium collections, we came upon isotype material of Splanchnomyces behrii, which represents a closely related species. Here we document the morphology and phylogenetic affinities of these unusual sequestrate Boletineae and transfer both species to Xerocomellus as X. macmurphyi and X. behrii. During our study, we also noted that the sequestrate taxon Rhopalogaster transversarius is nested within the epigeous genus Suillus.


Assuntos
Agaricales/classificação , Basidiomycota/classificação , Filogenia , Agaricales/citologia , Agaricales/genética , Basidiomycota/citologia , Basidiomycota/genética , Evolução Biológica , DNA Fúngico/genética , DNA Ribossômico/genética , Genes Fúngicos/genética , Análise de Sequência de DNA , Estados Unidos
3.
Fungal Biol ; 122(7): 701-716, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29880205

RESUMO

Moniliophthora roreri (Mr) causes frosty pod rot of Theobroma cacao in a hemibiotrophic association. The Mr biotroph-like phase has not been studied in culture. Mr spores (isolates Co12, Co52, and B3) were germinated on high (V8) and low (BPMM) nutrients with different media hardness (0.5% to 3% agarose). Germination was high on V8 media. Hardness affected germination on BPMM. Most colonies on V8 were slow-growing, failing to sporulate. Colony morphology depended on the isolate. On BPMM, exaggerated mycelia formed of limited length with enlarged cells. On agarose, rapidly expanding sporulating necrotrophic colonies formed rarely. Co12 and B3 spores were germinated on V8 and BPMM with low melting point (LMP) agarose. Slow-growing colonies of B3 on BPMM were unstable on LMP agarose, often forming slow-growing/rapidly expanding hybrids. Slow-growing colonies are hypothesized to represent the biotrophic phase. One nucleus was common in Mr cells, other than spores. Binucleate cells were occasionally observed in aged cells of slow-growing mycelia. Co52 cells often had more than two nuclei per cell after germination. Mr mycelia cells typically carry a single nucleus, being considered haploid. Biotroph- and necrotroph-like mycelia displayed differential gene expression but results were inconsistent with published in vivo results and require further study.


Assuntos
Agaricales/crescimento & desenvolvimento , Agaricales/citologia , Agaricales/fisiologia , Cacau/microbiologia , Núcleo Celular , Meios de Cultura , Micélio/citologia , Micélio/crescimento & desenvolvimento , Esporos Fúngicos/citologia , Esporos Fúngicos/crescimento & desenvolvimento
4.
Mycologia ; 110(3): 494-501, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29932817

RESUMO

Two new species in Lepiota sect. Ovisporae are described from tropical China. Lepiota angusticystidiata has a pileus with brownish yellow squamules covering a trichodermial palisade, ellipsoidal basidiospores, and narrowly clavate cheilocystidia; L. brunneosquamulosa has a tomentose, squamulose pileus with brownish yellow to yellowish brown concentric zones covering a trichodermial palisade, rarely with short elements, ellipsoidal or subcylindrical basidiospores with straight adaxial side, and no cheilocystidia. Phylogenetic relationships among species of sect. Ovisporae were inferred based on DNA sequences of the internal transcribed spacer region (ITS1-5.8S-ITS2 = ITS), the 5' end of the 28S gene (D1-D2-D3 variable domains), and partial sequences of the intergenic spacer (IGS1) of the nuc rDNA and the mitochondrial small ribosomal RNA gene (mtSSU), supporting the delineation of these new species.


Assuntos
Agaricales/classificação , Agaricales/citologia , Filogenia , Agaricales/genética , Agaricales/crescimento & desenvolvimento , Sequência de Bases , China , DNA Fúngico/genética , DNA Ribossômico/genética , Carpóforos , Hifas , Análise de Sequência de DNA , Especificidade da Espécie , Esporos Fúngicos
5.
Mycologia ; 110(3): 618-634, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29932839

RESUMO

The Inocybe geophylla group is circumscribed based on phylogenetic analysis of DNA sequences largely sampled from North America and Europe. Twenty-nine phylogenetic species are uncovered after analysis of combined nuc 28S rDNA (28S) and RNA polymerase II second largest subunit (rpb2) DNA sequence data. Species in the I. geophylla group share the presence of a cortina, silky-fibrillose pileus and stipe, pruinose stipe apex, spermatic odor, thick-walled hymenial cystidia, and smooth amygdaliform or elliptical basidiospores. Within the group, as many as five phylogenetic species attributable to I. lilacina and allies form a strongly supported clade based on analysis of nuc ITS1-5.8S-ITS2 rDNA (ITS [internal transcribed spacer]), 28S, and rpb2 data. However, all lilac-colored species do not form a monophyletic group. Sufficient morphological and ecological data are present to document four of the I. lilacina subgroup species, two of which are described from North America as new: I. ionocephala and I. sublilacina. Inocybe lilacina is recircumscribed based on sequencing the holotype and is distributed in the eastern United States under pines and/or hardwoods. Inocybe pallidicremea is a widespread and common conifer associate in mostly northern parts of North America, to which the name I. lilacina was previously applied. Descriptions, photographs, line drawings, and a taxonomic key to lilac species in the I. lilacina subgroup from North America are provided. Well-documented collections, especially notes on gross morphology and ecology, are needed to continue to assess and describe the high taxonomic variation in the I. lilacina subgroup and its allies worldwide.


Assuntos
Agaricales/classificação , Agaricales/citologia , Filogenia , Agaricales/genética , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , América do Norte , RNA Polimerase II/genética , RNA Ribossômico 28S/genética , Análise de Sequência de DNA , Especificidade da Espécie , Esporos Fúngicos , Traqueófitas/microbiologia
6.
J Comp Neurol ; 526(8): 1307-1328, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29427506

RESUMO

The peptidergic Pigment-dispersing factor (PDF)-Tri neurons are a group of non-clock neurons that appear transiently around the time of adult ecdysis (=eclosion) in the fruit fly Drosophila melanogaster. This specific developmental pattern points to a function of these neurons in eclosion or other processes that are active around pupal-adult transition. As a first step to understand the role of these neurons, we here characterize the anatomy of the PDF-Tri neurons. In addition, we describe a further set of peptidergic neurons that have been associated with eclosion behavior, eclosion hormone (EH), and crustacean cardioactive peptide (CCAP) neurons, to single cell level in the pharate adult brain. PDF-Tri neurons as well as CCAP neurons co-express a classical transmitter indicated by the occurrence of small clear vesicles in addition to dense-core vesicles containing the peptides. In the tritocerebrum, gnathal ganglion and the superior protocerebrum PDF-Tri neurites contain peptidergic varicosities and both pre- and postsynaptic sites, suggesting that the PDF-Tri neurons represent modulatory rather than pure interneurons that connect the subesophageal zone with the superior protocerebrum. The extensive overlap of PDF-Tri arborizations with neurites of CCAP- and EH-expressing neurons in distinct brain regions provides anatomical evidence for a possible function of the PDF-Tri neurons in eclosion behavior.


Assuntos
Agaricales/metabolismo , Proteínas de Drosophila/metabolismo , Neurônios/metabolismo , Neuropeptídeos/metabolismo , Agaricales/citologia , Animais , Animais Geneticamente Modificados , Drosophila , Proteínas de Drosophila/genética , Proteínas de Drosophila/ultraestrutura , Drosophila melanogaster , Hormônios de Inseto , Proteínas Luminescentes/genética , Proteínas Luminescentes/metabolismo , Microscopia Eletrônica , Neurônios/ultraestrutura , Neuropeptídeos/genética , Neurópilo/metabolismo , Neurópilo/ultraestrutura , Frações Subcelulares/metabolismo , Frações Subcelulares/ultraestrutura , Sinapsinas/metabolismo , Sinapsinas/ultraestrutura , Fatores de Transcrição/metabolismo
7.
Cell Mol Biol (Noisy-le-grand) ; 64(15): 78-83, 2018 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-30672440

RESUMO

Twenty-five specimens of coprinoid fungi were collected during an ongoing survey of agaric fungi in Kermanshah Province, western Iran. The specimens were identified based on morphological characteristics and molecular analysis of internal transcribed spacer sequences. Five species of Coprinellus viz C. disseminates, C. flocculosus, C. micaceus, C. radians and C. xanthothrix, three species of Coprinopsis viz C. atramentaria, C. insignis and C. semitalis and two species of Coprinus viz C. pinetorum and C. sterquilinus were identified. Among the species identified in this research, three unreported species from Iran namely C. insignis, C. semitalis and C. pinetorum are reported. Detailed morphological descriptions and illustrations of this three newly-recorded species were provided here and their evolutionary relationships were presented by the constructing of a phylogenetic tree.


Assuntos
Agaricales/citologia , Agaricales/genética , Agaricales/classificação , DNA Intergênico/genética , Irã (Geográfico) , Funções Verossimilhança , Filogenia
8.
Mycologia ; 109(4): 620-629, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29140762

RESUMO

Parasola represents an enigmatic lineage of veil-less, coprinoid fungi in Psathyrellaceae (Agaricales). The species-level taxonomy of the genus has been in a flux recently, resulting in the elimination of some long-established names and the description of new taxa. Here, we reconstruct the phylogeny of Parasola using two nuc rDNA loci, the internal transcribed spacer region (ITS1-5.8S-ITS2) and 28S and identify several putatively undescribed species, of which three are formally described here (Parasola crataegi, P. ochracea, and P. plicatilis-similis) based on molecular and morphological data. Morphological descriptions for the new species and an identification key to accepted Parasola species are given. We revise and discuss our current understanding of the phylogeny of Parasola.


Assuntos
Agaricales/classificação , Filogenia , Agaricales/citologia , Agaricales/genética , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Carpóforos , RNA Ribossômico 28S/genética , Esporos Fúngicos
9.
Mycologia ; 109(4): 578-587, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29020517

RESUMO

Cyphelloid fungi represent a polyphyletic assemblage of reduced agarics, including the brown-spored family Chromocyphellaceae. In order to elucidate the phylogenetic position of Chromocyphellaceae, newly generated sequences of Chromocyphella were included in a multigene alignment of the Agaricineae and phylogenetically analyzed. The current analyses show that the Chromocyphella muscicola specimen used to phylogenetically place Chromocyphellaceae in its original description was misidentified and that the Chromocyphellaceae nests in the Hymenogastraceae, Chromocyphella being sister to Flammula. Chromocyphella is emended, including now a new species with lamellate and stipitate basidiomata, C. lamellata. The name Cymbella crouanii, type species of Chromocyphella, is lecto- and epitypified. Our analyses support a new origin of cyphelloid fungi. The shift to a cyphelloid basidioma from an agaric ancestor is suggested to have occurred in two evolutionary steps in Chromocyphella, an initial reduction in basidioma size and a subsequent loss of lamellae and stipe.


Assuntos
Agaricales/classificação , Filogenia , Agaricales/citologia , Agaricales/genética , Teorema de Bayes , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Carpóforos , Proteínas Fúngicas/genética , Fator 1 de Elongação de Peptídeos/genética , RNA Polimerase I/genética , RNA Polimerase II/genética , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , Especificidade da Espécie , Esporos Fúngicos
10.
Bol. micol. (Valparaiso En linea) ; 32(1): 13-18, jun. 2017. ilus
Artigo em Espanhol | LILACS | ID: biblio-982637

RESUMO

El género Macrolepiota cuenta con 30 especies ampliamente distribuidas en el mundo, siendo éstas saprobiontes. En Chile se han documentado tres especies: M. procera, M. bonaerensis y M. rachodes, perteneciendo actualmente esta última al género Chlorophyllum. En esta revisión, se describen según la literatura los caracteres macromorfológicos y microscópicos de las tres especies mencionadas con anterioridad. Adicionalmente, se adaptó una clave dicotómica en base a la bibliografía para facilitar la determinación de las especies.


The Macrolepiota genus include 30 species widely distributed around the world, being these saprobionts. In Chile, three species have been documented: M. procera, M. bonaerensis y M. rachodes, at present the last specie currently belong to the genus Chlorophyllum. In this review, the macromorphological, and microscopic characteristics of the three species mentioned above are described according to the literature. In addition, a dichotomous key was adapted based on the bibliography to facilitate the determination of the species.


Assuntos
Agaricales/classificação , Agaricales/citologia , Basidiomycota , Ecossistema , Chile , Ecologia
11.
Mycologia ; 109(2): 296-307, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28463625

RESUMO

Suillus spraguei, synonym S. pictus, has been reported from eastern North America and eastern Asia associated with Pinus subgenus Strobus. Published phylogenetic analyses of rRNA internal transcribed spacer (ITS) sequence and population genetic studies indicated that S. spraguei as currently circumscribed might contain several geographically distinct species. This study examined this possibility through a multigene analysis of S. spraguei specimens from eastern North America and eastern Asia. These specimens were associated with Pinus strobus, P. koraiensis, P. armandii, and P. kwangtungensis. The multigene analysis included three genomic regions: the genes for translation elongation factor 1α (TEF1) and RNA polymerase II largest subunit (RPB1), and the nuc rRNA segments ITS1-5.8S-ITS2 (ITS) and 28S D1-D2 domains (28S). This study confirms that the S. spraguei complex consists of at least three cryptic species: S. spraguei sensu stricto associated with P. strobus in eastern North America; S. phylopictus associated with multiple species in Pinus subgenus Strobus (5-needle pines) throughout China and Japan; and S. kwangtungensis, currently found only in P. kwangtungensis forests in southeastern China. A third new species from Japan and Korea was suggested based on ITS phylogeny. Morphologically, S. spraguei and S. phylopictus resemble each other, whereas S. kwangtungensis is covered with more floccose scales. The new species add to the knowledge of macrofungal diversity in eastern Asia and highlight the necessity of comparing broadly distributed species complexes using morphological, molecular, and ecological data.


Assuntos
Agaricales/classificação , Filogenia , Agaricales/citologia , Agaricales/genética , Agaricales/isolamento & purificação , DNA Fúngico/genética , DNA Ribossômico/genética , DNA Espaçador Ribossômico/genética , Extremo Oriente , Carpóforos/citologia , Variação Genética , Técnicas de Tipagem Micológica , América do Norte , Fator 1 de Elongação de Peptídeos/genética , Pinus/microbiologia , RNA Polimerase II/genética , Especificidade da Espécie , Esporos Fúngicos/citologia
12.
Int J Med Mushrooms ; 19(2): 137-144, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28436322

RESUMO

Nomenclature revision and enlarged taxonomical descriptions are still needed for some well-known species whose interpretation is complicated by many nomenclature or taxonomical problems. The polyporoid fungus widely known as Trametes ochracea (= Coriolus zonatus) belongs to such a problematic group. At the same time, recent data show that this species, like its sister species T. versicolor, seems to be a perspective subject for fungal biotechnology and pharmacology. This article is devoted to stabilizing the nomenclature of the species in question via lectotypification and epitypification of Boletus multicolor. It will clarify the name T. multicolor as applied to this species is nomenclaturally correct and useful, free of further problems. An expanded species description and cultural characterization of epitype materials are presented.


Assuntos
Agaricales/classificação , Técnicas de Tipagem Micológica , Trametes/classificação , Agaricales/citologia , Agaricales/crescimento & desenvolvimento , Microscopia , Terminologia como Assunto , Trametes/citologia , Trametes/crescimento & desenvolvimento
13.
Mycologia ; 109(1): 55-63, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28402797

RESUMO

Three new species, Calocybe aurantiaca, C. convexa, and C. decolorata, are described based on collections made in Shenyang City, Liaoning Province, China. The main characters of C. aurantiaca are its orange-yellow sporocarps and small and smooth basidiospores. Calocybe convexa is characterized by its orange-buff pileus, very small basidiospores, and tortuous stipe, whereas C. decolorata is mainly characterized by its gills that turn blue when bruised. The sequences of nuc rDNA ITS1-5.8S-ITS2 (ITS) and the 28S D1-D5 region of the Calocybe species were analyzed, and the results indicated that the three new species belonged to the genus Calocybe and differed from other species of Calocybe. The morphological similarities of the new species to other Calocybe species and the classification system within the genus Calocybe based on molecular data are also discussed. A key is provided for the Calocybe species as reported from China in order to facilitate future studies of the genus.


Assuntos
Agaricales/classificação , Agaricales/citologia , Agaricales/genética , Agaricales/isolamento & purificação , China , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Microscopia , Filogenia , RNA Ribossômico 28S/genética , RNA Ribossômico 5,8S/genética , Análise de Sequência de DNA , Esporos Fúngicos/citologia
14.
Mycologia ; 109(5): 832-846, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29300677

RESUMO

We dekaryotized the multinucleate fungus Leucocoprinus gongylophorus, a symbiotic fungus cultivated vegetatively by leafcutter ants as their food. To track genetic changes resulting from dekaryotization (elimination of some nuclei from the multinuclear population), we developed two multiplex microsatellite fingerprinting panels (15 loci total), then characterized the allele profiles of 129 accessions generated by dekaryotization treatment. Genotype profiles of the 129 accessions confirmed allele loss expected by dekaryotization of the multinucleate fungus. We found no evidence for haploid and single-nucleus strains among the 129 accessions. Microscopy of fluorescently stained dekaryotized accessions revealed great variation in nuclei number between cells of the same vegetative mycelium, with cells containing typically between 3 and 15 nuclei/cell (average = 9.4 nuclei/cell; mode = 8). We distinguish four mycelial morphotypes among the dekaryotized accessions; some of these morphotypes had lost the full competence to produce gongylidia (nutritive hyphal-tip swellings consumed by leafcutter ants as food). In mycelial growth confrontations between different gongylidia-incompetent accessions, allele profiles suggest exchange of nuclei between dekaryotized accessions, restoring full gongylidia competence in some of these strains. The restoration of gongylidia competence after genetic exchange between dekaryotized strains suggests the hypothesis that complementary nuclei interact, or nuclear and cytoplasmic factors interact, to promote or enable gongylidia competence.


Assuntos
Agaricales/genética , Formigas/microbiologia , Núcleo Celular/genética , Hifas/crescimento & desenvolvimento , Hifas/genética , Poliploidia , Simbiose , Agaricales/citologia , Agaricales/fisiologia , Animais , Genótipo , Hifas/citologia , Microscopia
15.
Fungal Biol ; 120(9): 1065-76, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27567713

RESUMO

Although frequently found on mounds of the grass-cutting termite genus Trinervitermes, virtually nothing is known about the natural history of the fungal genus Podaxis (Agaricaceae) nor why it associates with termite mounds. More than 40 species of this secotioid genus have been described since Linnaeus characterised the first species in 1771. However, taxonomic confusion arose when most of these species were reduced to synonymy with Podaxis pistillaris in 1933. Although a few more species have since been described, the vast majority of specimens worldwide are still treated as P. pistillaris. Using 45 fresh and herbarium specimens from Southern Africa, four from North America and one each from Ethiopia, and Kenya, we constructed the first comprehensive phylogeny of the genus. Four of the genotyped specimens were more than 100 y old. With the exception of the type specimen of Podaxis rugospora, all herbarium specimens were labelled as P. pistillaris or Podaxis sp. However, our data shows that the genus contains at least five well-supported clades with significant inter-clade differences in spore length, width and wall thickness, and fruiting body length, supporting that clades likely represent distinct Podaxis species. Certain clades consistently associate with termites while others appear entirely free-living.


Assuntos
Agaricales/classificação , Agaricales/genética , Variação Genética , Isópteros/microbiologia , Filogenia , África , África Austral , Agaricales/citologia , Agaricales/isolamento & purificação , Animais , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Genes de RNAr , América do Norte , RNA Fúngico/genética , RNA Ribossômico/genética , Análise de Sequência de DNA , Esporos Fúngicos/citologia
16.
Mycologia ; 108(5): 869-881, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27302047

RESUMO

Moniliophthora perniciosa is a basidiomycete fungus that causes witches' broom disease in Theobroma cacao We analyzed the morphology and survival of fungal hyphae and endoplasmic reticulum (ER) remodeling in either glucose- or glycerol-grown M. perniciosa after treatment with ER stress-inducing chemicals dithiothreitol (DTT) or tunicamycin (TM). Changes in intracellular redox potential can cause endoplasmic reticulum (ER) stress due to diminished efficiency in protein folding that could in turn reduce cell survival. Such stress diminishes protein-folding efficiency that could in turn reduce cell survival. Light microscopy revealed morphological changes in hyphae after TM but not after DTT treatment, regardless of the media carbon source. Decrease in fungal survival, after both TM and DTT treatments, was dose-dependent and glycerol-grown cells showed a higher resistance to both chemicals compared to glucose-grown cells. Electron microscopy showed TM and DDT-induced ER stress in M. perniciosa as evidenced by structural alterations of the organelle. The volume of ER structures increased as a typical consequence of unfolded protein stress, and the number of autophagosomes was higher. In glycerol-grown fungus DTT treatment slightly induced expression of molecular chaperone BiP. The TM exposure-induced expression of gene MpIRE1, involved in signaling of the unfolded protein response, was higher in glycerol than glucose-grown cells. Such difference was not observable with expression of gene MpATG8, encoding a key protein in autosome formation, that was induced 1.4-fold and 1.2-fold in glucose or glycerol-grown cells, respectively. DHE-based fluorescence assay showed M. perniciosa oxidative stress induced by H2O2, and treated cells had a higher level of oxidative stress compared to control. A comprehensive study of remodeling of ER is important in understanding M. perniciosa fungus resistance to oxidative stress and its ability to implement a successful infection in T. cacao.


Assuntos
Agaricales/citologia , Agaricales/fisiologia , Estresse do Retículo Endoplasmático , Hifas/citologia , Agaricales/efeitos dos fármacos , Cacau , Ditiotreitol/toxicidade , Retículo Endoplasmático/ultraestrutura , Viabilidade Microbiana , Microscopia , Microscopia Eletrônica de Transmissão , Tunicamicina/toxicidade
18.
Mycologia ; 108(4): 820-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27055572

RESUMO

A novel, lignicolous agaric from Nothofagus forests of southern Chile is described as a new genus and species, Gymnopanella nothofagi This taxon falls within the family Omphalotaceae as a sister group to Gymnopus in phylogenetic analyses based on sequences spanning the internal transcribed spacer region and D1/D2 region of nuclear 28S rDNA. Morphologically it is characterized by convex to flabellate basidiomata with distinctly gelatinized trama, pileipellis in the form of a cutis with erect fascicles of cylindrical, spirally incrusted hyphae and nonamyloid, broadly ellipsoid basidiospores. This combination of features, in particular the lack of a rameales structure, serve to distinguish Gymnopanella from Gymnopus, Marasmiellus and other similar genera of the Omphalotaceae or Marasmiaceae. The new taxon is known only from Chilean Nothofagus forests at approximately 45-46° south latitude, but concerted searching in similar habitats in surrounding areas or in New Zealand may extend the known range considerably.


Assuntos
Agaricales/classificação , Agaricales/isolamento & purificação , Agaricales/citologia , Agaricales/genética , Chile , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA Ribossômico/química , DNA Ribossômico/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Fagales/microbiologia , Florestas , Hifas/citologia , Microscopia , Filogenia , RNA Ribossômico 28S/genética , Análise de Sequência de DNA , Esporos Fúngicos/citologia
19.
FEMS Microbiol Lett ; 363(9)2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-27030727

RESUMO

A ß-glycoside hydrolase was isolated from cell walls material in Coprinopsis cinerea elongating stipes. By analysis of SDS-PAGE, MALDI-TOF/TOF MS and substrate specificity, this enzyme was characterized as an extracellular ß-glucosidase which is a trimer consisting of three homosubunits. ß-Glucosidase did not degrade ß-glucans with modified ends, whereas it hydrolyzed various ß-glucans with free ends and related oligosaccharides with ß-1,3-, ß-1,4- or ß-1,6-linkages. Although this ß-glucosidase possesses glycosyltransferase activity on laminarioligosaccharides, it did not transfer glucose residues from laminaritriose to ß-glucan in stipe cell walls to produce larger ß-glucan molecules; instead, it caused a decrease in the molecular size of stipe wall ß-glucan by removing glucose. Relatively, the molecular size of wall ß-glucans in the elongating apical stipe was less than that found in the non-elongating basal stipes, and this ß-glucosidase was more highly expressed in the elongating apical stipe than in non-elongating basal regions. Therefore, we propose that ß-glucosidase functions by trimming or cutting the ß-glucan side chains on the ß-1,3-glucan backbone to prevent them from forming longer branches, keeping the wall plastic to promote diffuse wall growth.


Assuntos
Agaricales/enzimologia , Agaricales/crescimento & desenvolvimento , beta-Glucanas/metabolismo , beta-Glucosidase/metabolismo , Agaricales/citologia , Parede Celular/enzimologia , Parede Celular/metabolismo , Eletroforese em Gel de Poliacrilamida , Glicosiltransferases , Hidrólise , Oligossacarídeos/metabolismo , beta-Glucanas/química , beta-Glucosidase/química , beta-Glucosidase/genética , beta-Glucosidase/isolamento & purificação
20.
Mycorrhiza ; 26(3): 177-88, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26215114

RESUMO

Arbutoid mycorrhizae were synthesized in vitro between Arbutus unedo L. and two isolates of Lactarius deliciosus. The fungal isolates were obtained from sporocarps collected under Pinus sylvestris and in a mixed forest stand of Quercus suber and Pinus pinea. Synthesis tubes filled with a mixture of sterilized peat, vermiculite, and perlite imbibed with nutrient solution were used. Two inoculation methods using solid and liquid media were tested. Shoots from an adult selected clone of A. unedo were used after in vitro rooting by auxin dipping. After 3 months of shoots transfer to the substrate, the root systems were examined for arbutoid mycorrhizae formation and later on ex vitro conditions, 9 months after acclimatization. The inoculum treatment with liquid medium improved the mycorrhizal development for both isolates, in vitro. Sterilized substrate for plant acclimatization increased the mycorrhizal development. The arbutoid mycorrhizae were observed in vitro as well as 9 months after acclimatization. Standard arbutoid mycorrhiza features were observed: pale yellow mantle, typical cruciform appearance, Hartig net (HN), and intracellular hyphal complexes, both confined to the epidermis. L. deliciosus mycorrhizae synthetized in vitro persisted 9 months after plant acclimatization. Morphological observations were confirmed by molecular techniques.


Assuntos
Agaricales/crescimento & desenvolvimento , Ericaceae/microbiologia , Micorrizas/crescimento & desenvolvimento , Aclimatação , Agaricales/citologia , Agaricales/isolamento & purificação , Hifas/crescimento & desenvolvimento , Micorrizas/genética , Pinus/microbiologia , Pinus sylvestris/microbiologia , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Brotos de Planta/microbiologia , Árvores/microbiologia
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