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1.
Int J Syst Evol Microbiol ; 70(2): 1178-1185, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31860431

RESUMO

During a survey of endophytic fungi in plant roots in secondary forests in Yunnan, China, a novel ascomyceteous taxon, Beltrania sinensis, was isolated from Quercus cocciferoides Hand.-Mazz. and Fraxinus malacophylla Hemsl. This novel species is characterized by having oval or obovoid conidiogenous cells with several apical, flat-tipped denticles, and biconic, aseptate, smooth, pale brown conidia with a hyaline to subhyaline equatorial transverse band and apical tubular appendage. Phylogenetic analysis of the combined sequences of the internal transcribed spacer and the LSU rRNA gene confirmed its novel species status within the genus Beltrania. Here, the novel species is described and illustrated, and a taxonomic key to species in the genus Beltrania is provided.


Assuntos
Filogenia , Raízes de Plantas/microbiologia , Quercus/microbiologia , Xylariales/classificação , China , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Técnicas de Tipagem Micológica , Análise de Sequência de DNA , Esporos Fúngicos , Xylariales/isolamento & purificação
2.
Mycologia ; 111(2): 265-273, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30856060

RESUMO

A novel species of Microdochium was identified as the causal agent of a leaf blight of Poa pratensis (Kentucky blue grass) and Agrostis stolonifera (Creeping bentgrasses), two cold-season turfgrasses widely grown on golf courses in northern China. This disease first appears as small, water-soaked, and scattered leaf spots. Under conditions of high temperatures and successive days of rain, the infected leaves rapidly lose their integrity and large diseased patches appear. Fungal strains were isolated from blighted leaf spots. A phylogenetic analysis based on the nuc rDNA internal transcribed spacer regions and 5.8S rRNA gene (ITS1-5.8S-ITS2 = ITS) and parts of the ß-tubulin (TUB2) and RNA polymerase II second largest subunit (RPB2) genes strongly supported that these isolates are a distinct evolutionary lineage in Microdochium (Microdochiaceae, Xylariales) that represents a new taxonomic species, herein named as M. poae. Microscopic characters confirmed that these strains were morphologically distinct from known Microdochium species. The pathogenicity of M. poae was confirmed by inoculating spore suspension on both grasses and reisolation of the pathogen from symptomatic tissues. The optimal growth temperature suggests that the occurrence of the new leaf blight disease caused by M. poae was significantly different from the microdochium patch disease caused by M. nivale.


Assuntos
Agrostis/microbiologia , Doenças das Plantas/microbiologia , Poa/microbiologia , Xylariales/classificação , Xylariales/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 , RNA Polimerases Dirigidas por DNA/genética , Kentucky , Microscopia , Filogenia , Folhas de Planta/microbiologia , RNA Ribossômico 5,8S/genética , Análise de Sequência de DNA , Tubulina (Proteína)/genética , Xylariales/citologia , Xylariales/genética
3.
Microbiologyopen ; 8(4): e00666, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-29926537

RESUMO

The endophytic fungi Muscodor spp. produce volatile organic compounds (VOCs) which can inhibit and even kill pathogenic fungi, bacteria, and nematodes. Nine endophytic fungal strains, isolated from the shoots of gramineous plants including Arthraxon hispidus, Eleusine indica, Oplismenus undulatifolius, and Oryza granulata, were identified as Muscodor through phylogenetic analysis of the internal transcribed spacer. Through an SPSS K-means cluster analysis, the nine Muscodor strains were divided into four groups based on the antifungal activities of the VOCs produced by these fungi determined by a two-section confrontation test. The first group contains the strains Y-L-54, W-S-41, Y-S-35, W-T-27, and Y-L-56, which showed the strongest activity. The second and third groups contain W-S-35 and Y-L-43, which showed stronger and moderate activity, respectively. The fourth group contains W-S-38 and N-L-7, which were the weakest in inhibiting the tested pathogens. Thirty-five compounds and the relative amounts of VOCs were determined by SPME-GC-MS and comparison with the NIST14 mass spectrometry database and Agilent MassHunter qualitative and quantitative analyses. These 35 compounds were classified into two different categories: (a) the product of fatty acid degradation, and (b) the intermediate and final metabolite of the metabolic pathway with the precursor of mevalonic acid. SPSS clustering analysis showed that the chemical components of VOCs might be correlated with their bioactivity rather than their phylogenetic assignment and some of the identified compounds might be responsible for antifungal activity. In conclusion, new Muscodor endophytes were recorded in tropical gramineous plants and a number of strains showed remarkable bioactive properties. Therefore, they have important potential applications in the fields of plant disease control.


Assuntos
Endófitos/isolamento & purificação , Plantas/microbiologia , Xylariales/isolamento & purificação , Antifúngicos/química , Antifúngicos/metabolismo , China , Endófitos/classificação , Endófitos/genética , Endófitos/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Filogenia , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo , Xylariales/classificação , Xylariales/genética , Xylariales/metabolismo
4.
Mycologia ; 110(4): 726-749, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30067469

RESUMO

Twenty-five fructicolous and seminicolous species of Xylaria are classified into three groups by stromatal morphology: (i) the X. ianthinovelutina group; (ii) the X. carpophila group; and (iii) the X. heloidea group. Xylaria reevesiae, X. rossmanae, and X. vivantii are described as new species. Xylaria reevesiae belongs to the X. carpophila group, resembling X. euphorbiicola but differing from it mainly by having conspicuous perithecial mounds and growing on fallen fruits of a different host plant. Xylaria rossmanae and X. vivantii belong to the X. ianthinovelutina group. Xylaria rossmanae differs from the species of the group mainly by larger, paler, fusoid-inequilateral ascospores, and X. vivantii differs by larger ascospores with a slightly oblique germ slit. A dichotomous key is provided for identifying the 25 species. Doubtful names are also listed and annotated.


Assuntos
Frutas/microbiologia , Sementes/microbiologia , Xylariales/classificação , Xylariales/isolamento & purificação , DNA Fúngico/genética , DNA Espaçador Ribossômico , Filogenia , Análise de Sequência de DNA , Especificidade da Espécie , Esporos Fúngicos , Xylariales/genética
5.
PLoS One ; 13(6): e0198321, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29949590

RESUMO

Surveys of foliar endophytes from the Acadian forest region over the past three decades have identified numerous phylogenetically diverse fungi producing natural products toxic to forest pests and diseases. The life histories of some conifer endophytes can be restricted to plant foliage or may include saprotrophic phases on other plants tissues or even alternate hosts. Considering the potentially broad host preferences of conifer endophytes we explored fungi isolated from understory species and their metabolites as part of an ongoing investigation of fungal biodiversity from the Acadian forest. We report a hitherto unidentified Xylariomycetidae species isolated from symptomatic Labrador tea (Rhododendron groenlandicum) leaves and mountain laurel (Kalmia latifolia) collected in coastal southern New Brunswick, Canada. Morphological and phylogenetic evidence demonstrated the unknown species was a novel Synnemapestaloides (Sporocadaceae) species, described here as Syn. ericacearum. A preliminary screening assay indicated that the culture filtrate extract of the new species was potently antifungal towards the biotrophic pathogen Microbotryum violaceum, warranting an investigation of its natural products. Two natural products possessing a rare 1,3-benzodioxin-4-one scaffold, synnemadoxins A-B (1-2), and their postulated precursor, synnemadiacid A (3), were characterized as new structures and assessed for antimicrobial activity. All isolated compounds elicited in vitro inhibitory antifungal activity towards M. violaceum at 2.3 µg mL-1 and moderate antibiotic activity. Further, the characterization of synnemadoxins A-B provided a perspective on the biosynthesis of some related 1,3-benzodioxin-4-ones produced by other fungi within the Xylariales.


Assuntos
Dioxóis/isolamento & purificação , Ericaceae/microbiologia , Ledum/microbiologia , Xylariales/química , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Anti-Infecciosos/farmacologia , Bactérias/efeitos dos fármacos , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Produtos Biológicos/farmacologia , Dioxóis/química , Dioxóis/farmacologia , Estrutura Molecular , Novo Brunswick , Filogenia , Folhas de Planta/microbiologia , Xylariales/classificação , Xylariales/isolamento & purificação
6.
Mycologia ; 110(2): 434-447, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29792784

RESUMO

In 2010-2011, a Xylaria sp. was documented growing from seeds of both Chlorocardium rodiei and Chlorocardium venenosum, a commercially valuable timber in Guyana. We conducted extensive surveys in 2015-2016, where this Xylaria sp. was observed fruiting from ca. 80% of dispersed seeds in both natural and logged forests in the Upper Demerara-Berbice, Potaro-Siparuni, and the Cuyuni-Mazaruni districts of central Guyana. Species of Xylaria are ascomycetous fungi generally characterized by black, carbonaceous, multiperitheciate ascoma commonly found growing on dead wood. Combined teleomorphic and molecular data indicate that the fungus represents a novel species, described here as Xylaria karyophthora.


Assuntos
Lauraceae/microbiologia , Sementes/microbiologia , Xylariales/classificação , Xylariales/isolamento & purificação , Actinas/genética , Florestas , Guiana , Técnicas Microbiológicas , Microscopia , Filogenia , Reação em Cadeia da Polimerase , RNA Polimerase II/genética , Análise de Sequência de DNA , Xylariales/citologia , Xylariales/genética
7.
Nat Prod Rep ; 35(9): 992-1014, 2018 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-29774351

RESUMO

Covering: up to December 2017 The diversity of secondary metabolites in the fungal order Xylariales is reviewed with special emphasis on correlations between chemical diversity and biodiversity as inferred from recent taxonomic and phylogenetic studies. The Xylariales are arguably among the predominant fungal endophytes, which are the producer organisms of pharmaceutical lead compounds including the antimycotic sordarins and the antiparasitic nodulisporic acids, as well as the marketed drug, emodepside. Many Xylariales are "macromycetes", which form conspicuous fruiting bodies (stromata), and the metabolite profiles that are predominant in the stromata are often complementary to those encountered in corresponding mycelial cultures of a given species. Secondary metabolite profiles have recently been proven highly informative as additional parameters to support classical morphology and molecular phylogenetic approaches in order to reconstruct evolutionary relationships among these fungi. Even the recent taxonomic rearrangement of the Xylariales has been relying on such approaches, since certain groups of metabolites seem to have significance at the species, genus or family level, respectively, while others are only produced in certain taxa and their production is highly dependent on the culture conditions. The vast metabolic diversity that may be encountered in a single species or strain is illustrated based on examples like Daldinia eschscholtzii, Hypoxylon rickii, and Pestalotiopsis fici. In the future, it appears feasible to increase our knowledge of secondary metabolite diversity by embarking on certain genera that have so far been neglected, as well as by studying the volatile secondary metabolites more intensively. Methods of bioinformatics, phylogenomics and transcriptomics, which have been developed to study other fungi, are readily available for use in such scenarios.


Assuntos
Produtos Biológicos/metabolismo , Produtos Biológicos/farmacologia , Metabolismo Secundário/genética , Xylariales/metabolismo , Animais , Biodiversidade , Produtos Biológicos/química , Endófitos/química , Endófitos/metabolismo , Genoma Fúngico , Insetos/microbiologia , Estrutura Molecular , Filogenia , Xylariales/química , Xylariales/classificação , Xylariales/genética
8.
Rapid Commun Mass Spectrom ; 32(10): 815-823, 2018 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-29499079

RESUMO

RATIONALE: Although the fruiting-body of the fungi of the genus Xylaria shows a great variety of morphological characteristics, their mycelial forms are always very similar, imposing difficulties for their identification. Intact cell mass spectrometry (ICMS) using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) can be a fast and reliable strategy to support the differentiation/identification of Xylaria species in those cases where fruit-bodies are not available. METHODS: Many experimental parameters such as sample preparation and culture media are crucial for filamentous fungi analysis by MALDI-TOFMS. For the purposes of this study, we used four matrices (CHCA, DHB, FA and SA) with five different concentrations (0.1, 0.3, 0.5, 1.0 and 2.5%) of TFA in the matrix, the influence of six different culture media (solid and liquid), and three mycelium peptide/protein extraction protocols (acid, basic and thymol-supported solution) to optimize the sample preparation of the endophytic fungus X. arbuscula. RESULTS: It was observed that sinapinic acid (30 mg/mL) dissolved in acetonitrile/0.1% TFA and PDA were the best matrix solution and culture medium, respectively, for the ICMS of X. arbuscula. The formic acid and ammonium bicarbonate (AB) protocols provided similar mass spectra; however, a higher number of peaks were observed using AB extraction. Mass spectra obtained from different thymol-containing solutions (EtOH/aqueous 0.1% TFA and ACN/aqueous 0.1% TFA) show increasing peak abundances at m/z 3000-6500. CONCLUSIONS: X. arbuscula could be analyzed by ICMS. However, an extraction step was required to provide suitable MALDI mass spectra. Formic acid-, AB- and thymol-containing solutions were demonstrated to be good cocktails for the extraction of peptide/protein biomarkers from these fungi.


Assuntos
Proteínas Fúngicas/análise , Micélio/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Xylariales/química , Bicarbonatos/química , Fracionamento Químico/métodos , Ácidos Cumáricos/química , Meios de Cultura/química , Formiatos/química , Proteínas Fúngicas/isolamento & purificação , Micélio/classificação , Peptídeos/análise , Peptídeos/isolamento & purificação , Timol/química , Ácido Trifluoracético/química , Xylariales/classificação
9.
Sci Rep ; 8(1): 1740, 2018 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-29379181

RESUMO

In recent years, fungi have been shown to produce a plethora of new bioactive secondary metabolites of interest, as new lead structures for medicinal and other pharmacological applications. The present investigation was carried out to study the pharmacological properties of a potent and major bioactive compound: xylaranic acid, which was obtained from Xylaria primorskensis (X. primorskensis) terpenoids in terms of antibacterial activity, antioxidant potential against DPPH & H2O2 radicals and anticancer activity against human lung cancer cells. Due to terpenoid nature, low water solubility and wretched bioavailability, its pharmacological use is limited. To overcome these drawbacks, a novel xylaranic acid silver nanoparticle system (AgNPs) is developed. In addition to improving its solubility and bioavailability, other advantageous pharmacological properties has been evaluated. Furthermore, enhanced anticancer activity of xylaranic acid and its AgNPs due to induced apoptosis were also confirmed by determining the expression levels of apoptosis regulatory genes p53, bcl-2 and caspase-3 via qRT PCR method. This is the first study developing the novel xylaranic acid silver nanoparticle system and enlightening its therapeutic significance with its improved physico-chemical properties and augmented bioactive potential.


Assuntos
Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Antioxidantes/farmacologia , Portadores de Fármacos , Nanopartículas Metálicas , Terpenos/farmacologia , Xylariales/química , Células A549 , Antibacterianos/isolamento & purificação , Antibacterianos/farmacocinética , Antineoplásicos/isolamento & purificação , Antineoplásicos/farmacocinética , Antioxidantes/isolamento & purificação , Antioxidantes/farmacocinética , Apoptose , Proteínas Reguladoras de Apoptose/biossíntese , Proteínas Reguladoras de Apoptose/genética , Sobrevivência Celular/efeitos dos fármacos , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/fisiologia , Depuradores de Radicais Livres/farmacologia , Perfilação da Expressão Gênica , Humanos , Concentração Inibidora 50 , Testes de Sensibilidade Microbiana , Prata , Solubilidade , Terpenos/isolamento & purificação , Terpenos/farmacocinética , Xylariales/classificação , Xylariales/genética , Xylariales/isolamento & purificação
10.
Plant Dis ; 102(1): 98-106, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30673469

RESUMO

Gray blight of tea, caused by several Pestalotiopsis-like species, is one of the most destructive foliar diseases in tea cultivation yet the characteristics of these pathogens have not been confirmed until now. With morphological and multigene phylogenetic analyses, we have identified the gray blight fungi as Pseudopestalotiopsis camelliae-sinensis, Neopestalotiopsis clavispora, and Pestalotiopsis camelliae. Phylogenetic analyses derived from the combined internal transcribed spacer, ß-tubulin, and translation elongation factor 1-α gene regions successfully resolved most of the Pestalotiopsis-like species used in this study with high bootstrap supports and revealed three major clusters representing these three species. Differences in colony appearance and conidia morphology (shape, size, septation, color and length of median cells, and length and number of apical and basal appendages) were consistent with the phylogenetic grouping. Pathogenicity tests validated that all three species isolated from tea leaves were causal agents of gray blight disease on tea plant (Camellia sinensis). This is the first description of the characteristics of the three species Pseudopestalotiopsis camelliae-sinensis, N. clavispora, and Pestalotiopsis camelliae as causal agents of tea gray blight disease in China.


Assuntos
Proteínas de Bactérias/análise , Camellia sinensis/microbiologia , Doenças das Plantas/microbiologia , RNA Bacteriano/análise , Xylariales/classificação , Xylariales/fisiologia , China , Filogenia , Análise de Sequência de DNA , Xylariales/genética
11.
Plant Dis ; 102(1): 220-230, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30673471

RESUMO

Recent studies in grape-growing areas including Australia, California, and Spain have revealed an extensive diversity of Diatrypaceae species on grapevines showing dieback symptoms and cankers. However, in South Africa, little is known regarding the diversity of these species in vineyards. The aim of this study was, therefore, to identify and characterize Diatrypaceae species associated with dieback symptoms of grapevine in South Africa. Isolates were collected from dying spurs of grapevines aged 4 to 8 years old, grapevine wood showing wedge-shaped necrosis when cut in cross section as well as from perithecia on dead grapevine wood. The collected isolates were identified based on morphological characters and phylogenetic analyses of the internal transcribed spacer region (ITS) and ß-tubulin gene. Seven Diatrypaceae species were identified on grapevine, namely Cryptovalsa ampelina, C. rabenhorstii, Eutypa consobrina, E. lata, E. cremea sp. nov., Eutypella citricola, and E. microtheca. The dying spurs yielded the highest diversity of species when compared with the wedge-shaped necrosis and/or perithecia. C. ampelina was the dominant species in the dying spurs, followed by E. citricola, whereas E. lata was the dominant species isolated from the wedge-shaped necroses and perithecia. These results confirm E. lata as an important grapevine canker pathogen in South Africa, but the frequent association of C. ampelina with spur dieback suggests that this pathogen plays a more prominent role in dieback than previously assumed. In some cases, more than one species were isolated from a single symptom, which suggests that interactions may be occurring leading to decline of grapevines. C. rabenhorstii, E. consobrina, E. citricola, E. microtheca, and E. cremea are reported for the first time on grapevine in South Africa.


Assuntos
Doenças das Plantas/microbiologia , Vitis/microbiologia , Xylariales/classificação , Xylariales/fisiologia , Proteínas Fúngicas/análise , Filogenia , RNA Fúngico/análise , África do Sul , Tubulina (Proteína)/análise , Xylariales/genética
12.
Plant Dis ; 102(7): 1402-1409, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30673568

RESUMO

Stone fruit trees (Prunus spp.) are economically important fruit trees cultivated in South Africa. These trees are often grown in close proximity to vineyards and are to a large extent affected by the same trunk disease pathogens as grapevines. The aim of the present study was to determine whether stone fruit trees are inhabited by Diatrypaceae species known from grapevines and whether these trees could act as alternative hosts for these fungal species. Isolations were carried out from symptomatic wood of Prunus species (almond, apricot, cherry, nectarine, peach, and plum) in stone fruit growing areas in South Africa. Identification of isolates was based on phylogenetic analyses of the internal transcribed spacer region and ß-tubulin gene. Forty-six Diatrypaceae isolates were obtained from a total of 380 wood samples, from which five species were identified. All five species have also been associated with dieback of grapevine. The highest number of isolates was found on apricot followed by plum. No Diatrypaceae species were isolated from peach and nectarine. Eutypa lata was the dominant species isolated (26 isolates), followed by Cryptovalsa ampelina (7), Eutypa cremea (5), Eutypella citricola (5), and Eutypella microtheca (3). First reports from Prunus spp. are E. cremea, E. citricola, and E. microtheca. Pathogenicity tests conducted on apricot and plum revealed that all these species are pathogenic to these hosts, causing red-brown necrotic lesions like those typical of Eutypa dieback on apricot.


Assuntos
Frutas/microbiologia , Doenças das Plantas/microbiologia , Prunus/microbiologia , Vitis/microbiologia , Xylariales/patogenicidade , DNA Espaçador Ribossômico/genética , Proteínas Fúngicas/genética , Especificidade de Hospedeiro/genética , Filogenia , Prunus/classificação , África do Sul , Especificidade da Espécie , Tubulina (Proteína)/genética , Virulência/genética , Madeira/microbiologia , Xylariales/classificação , Xylariales/genética
13.
Appl Microbiol Biotechnol ; 101(6): 2603-2618, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28078400

RESUMO

Recently, several endophytic fungi have been demonstrated to produce volatile organic compounds (VOCs) with properties similar to fossil fuels, called "mycodiesel," while growing on lignocellulosic plant and agricultural residues. The fact that endophytes are plant symbionts suggests that some may be able to produce lignocellulolytic enzymes, making them capable of both deconstructing lignocellulose and converting it into mycodiesel, two properties that indicate that these strains may be useful consolidated bioprocessing (CBP) hosts for the biofuel production. In this study, four endophytes Hypoxylon sp. CI4A, Hypoxylon sp. EC38, Hypoxylon sp. CO27, and Daldinia eschscholzii EC12 were selected and evaluated for their CBP potential. Analysis of their genomes indicates that these endophytes have a rich reservoir of biomass-deconstructing carbohydrate-active enzymes (CAZys), which includes enzymes active on both polysaccharides and lignin, as well as terpene synthases (TPSs), enzymes that may produce fuel-like molecules, suggesting that they do indeed have CBP potential. GC-MS analyses of their VOCs when grown on four representative lignocellulosic feedstocks revealed that these endophytes produce a wide spectrum of hydrocarbons, the majority of which are monoterpenes and sesquiterpenes, including some known biofuel candidates. Analysis of their cellulase activity when grown under the same conditions revealed that these endophytes actively produce endoglucanases, exoglucanases, and ß-glucosidases. The richness of CAZymes as well as terpene synthases identified in these four endophytic fungi suggests that they are great candidates to pursue for development into platform CBP organisms.


Assuntos
Endófitos/enzimologia , Proteínas Fúngicas/metabolismo , Genoma Fúngico , Lignina/metabolismo , Xylariales/enzimologia , Alquil e Aril Transferases/genética , Alquil e Aril Transferases/metabolismo , Biocombustíveis , Celulase/genética , Celulase/metabolismo , Celulases/genética , Celulases/metabolismo , Endófitos/classificação , Endófitos/genética , Proteínas Fúngicas/genética , Expressão Gênica , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Monoterpenos/metabolismo , Filogenia , Polissacarídeos/metabolismo , Sesquiterpenos/metabolismo , Compostos Orgânicos Voláteis/metabolismo , Xylariales/classificação , Xylariales/genética
14.
Microb Ecol ; 73(4): 954-965, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27924400

RESUMO

Muscodor spp. are proficient producers of bioactive volatile organic compounds (VOCs) with many potential applications. However, all members of this genus produce varying amounts and types of VOCs which suggests the involvement of epigenetics as a possible explanation. The members of this genus are poorly explored for the production of soluble compounds (extrolites). In this study, the polyketide synthase (PKS) and non-ribosomal peptide synthetase (NRPS) genes from an endophyte, Muscodor yucatanensis Ni30, were cloned and sequenced. The PKS genes belonged to reduced, partially reduced, non-reduced, and highly reduced subtypes. Strains over-expressing PKS genes were developed through the use of small-molecule epigenetic modifiers (suberoylanilide hydroxamic acid (SAHA) and 5-azacytidine). The putative epigenetic variants of this organism differed considerably from the wild type in morphological features and cultural characteristics as well as metabolites that were produced. Each variant produced a different set of VOCs distinct from the wild type, and several VOCs including methyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)hexane-2,4-diol and 2-carboxymethyl-3-n-hexylmaleic appeared in the variant strains, the production of which could be attributed to the activity of otherwise silent PKS genes. The bioactive extrolite brefeldin A was isolated and characterized from the wild type. However, this metabolite was not detected in EV-1, but instead, two other products were isolated and characterized as ergosterol and xylaguaianol C. Hence, M. yucatanensis has the genetic potential to produce several previously undetectable VOCs and organic solvent soluble products. It is also the case that small-molecule epigenetic modifiers can be used to produce stable variant strains of fungi with the potential to produce new molecules. Finally, this work hints to the prospect that the epigenetics of an endophytic microorganism can be influenced by any number of environmental and chemical factors associated with its host plant which may help to explain the enormous chemical diversity of secondary metabolic products found in Muscodor spp.


Assuntos
Endófitos/enzimologia , Endófitos/genética , Epigenômica , Regulação Fúngica da Expressão Gênica/genética , Metabolismo Secundário/genética , Xylariales/enzimologia , Xylariales/genética , Sequência de Aminoácidos , Azacitidina/metabolismo , Brefeldina A/metabolismo , DNA Fúngico , Endófitos/metabolismo , Ergosterol/metabolismo , Genes Fúngicos , Ácidos Hidroxâmicos/metabolismo , Peptídeo Sintases/química , Peptídeo Sintases/genética , Fenótipo , Filogenia , Policetídeo Sintases/química , Policetídeo Sintases/genética , Reação em Cadeia da Polimerase/métodos , Conformação Proteica , Alinhamento de Sequência , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo , Vorinostat , Xylariales/classificação , Xylariales/metabolismo
15.
Int J Med Mushrooms ; 18(3): 253-60, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27481159

RESUMO

White jelly mushroom, Tremella fuciformis, is a popular edible mushroom with interesting medicinal properties (e.g., immunostimulating, antidiabetic). The formation of T. fuciformis basidiomes is highly dependent on the presence of a specific host fungus, both in nature and for industrial production. This host has traditionally been indicated as "Xianghui" in China, yet which or how many fungal species Xianghui comprises is unclear, with various authorities claiming different species. At present, Annulohypoxilon archeri is generally assumed to be the main Xianghui species, but this has not yet been confirmed experimentally. The implementation of older, premolecular-based research data (i.e., morphological) with present, sequence-based data to solve the identity remains confusing and studies addressing both identification methods in combination are lacking. The unclear identity of Xianghui is a major obstacle for further understanding of the important relationship between the host(s) and T. fuciformis. In this study, we collected a wild specimen of T. fuciformis together with several nearby stroma of Xianghui, cocultivated T. fuciformis with the Xianghui isolates, and observed basidiome formation. Internal transcribed spacer (ITS) sequence analysis showed that all Xianghui spore isolates belonged to the same species and both morphological analysis of sexual stages and ITS ß-tubulin and actin gene sequences of the Xianghui specified it as Annulohypoxylon stygium. The ITS sequences of the newly identified Xianghui further closely matched those of the Xianghui strains used in the mushroom industry, showing that wild and culture spawn Xianghui in China consist of A. stygium. In contrast with previous conclusions, A. stygium, and not A. archeris, seems to be the preferred host of T. fuciformis.


Assuntos
Basidiomycota/classificação , Xylariales/classificação , Basidiomycota/citologia , Basidiomycota/genética , Carpóforos , Filogenia , Análise de Sequência de DNA , Xylariales/citologia , Xylariales/genética
16.
Curr Microbiol ; 73(2): 280-6, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27155842

RESUMO

For screening bilobalide (BB)-producing endophytic fungi from medicinal plant Ginkgo biloba, a total of 57 fungal isolates were isolated from the internal stem, root, leaf, and bark of the plant G. biloba. Fermentation processes using BB-producing fungi other than G. biloba may become a novel way to produce BB, which is a terpene trilactones exhibiting neuroprotective effects. In this study, a BB-producing endophytic fungal strain GZUYX13 was isolated from the leaves of G. biloba grown in the campus of Guizhou University, Guiyang city, Guizhou province, China. The strain produced BB when grown in potato dextrose liquid medium. The amount of BB produced by this endophytic fungus was quantified to be 106 µg/L via high-performance liquid chromatography (HPLC), substantially lower than that produced by the host tissue. The fungal BB which was analyzed by thin layer chromatography (TLC) and HPLC was proven to be identical to authentic BB. The strain GZUYX13 was identified as Pestalotiopsis uvicola via morphology and ITS rDNA phylogeny. To the best of our knowledge, this is the first report concerning the isolation and identification of endophytic BB-producing Pestalotiopsis spp. from the host plant, which further proved that endophytic fungi have the potential to produce bioactive compounds.


Assuntos
Ciclopentanos/metabolismo , Endófitos/metabolismo , Furanos/metabolismo , Ginkgo biloba/microbiologia , Ginkgolídeos/metabolismo , Plantas Medicinais/microbiologia , Xylariales/metabolismo , Endófitos/classificação , Endófitos/genética , Endófitos/isolamento & purificação , Folhas de Planta/microbiologia , Xylariales/classificação , Xylariales/genética , Xylariales/isolamento & purificação
17.
Mol Phylogenet Evol ; 98: 210-32, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26903035

RESUMO

The Xylariaceae (Sordariomycetes) comprise one of the largest and most diverse families of Ascomycota, with at least 85 accepted genera and ca. 1343 accepted species. In addition to their frequent occurrence as saprotrophs, members of the family often are found as endophytes in living tissues of phylogenetically diverse plants and lichens. Many of these endophytes remain sterile in culture, precluding identification based on morphological characters. Previous studies indicate that endophytes are highly diverse and represent many xylariaceous genera; however, phylogenetic analyses at the family level generally have not included endophytes, such that their contributions to understanding phylogenetic relationships of Xylariaceae are not well known. Here we use a multi-locus, cumulative supermatrix approach to integrate 92 putative species of fungi isolated from plants and lichens into a phylogenetic framework for Xylariaceae. Our collection spans 1933 isolates from living and senescent tissues in five biomes across the continental United States, and here is analyzed in the context of previously published sequence data from described species and additional taxon sampling of type specimens from culture collections. We found that the majority of strains obtained in our surveys can be classified in the hypoxyloid and xylaroid subfamilies, although many also were found outside of these lineages (as currently circumscribed). Many endophytes were placed in lineages previously not known for endophytism. Most endophytes appear to represent novel species, but inferences are limited by potential gaps in public databases. By linking our data, publicly available sequence data, and records of ascomata, we identify many geographically widespread, host-generalist clades capable of symbiotic associations with diverse photosynthetic partners. Concomitant with such cosmopolitan host use and distributions, many xylariaceous endophytes appear to inhabit both living and non-living plant tissues, with potentially important roles as saprotrophs. Overall, our study reveals major gaps in the availability of multi-locus datasets and metadata for this iconic family, and provides new hypotheses regarding the ecology and evolution of endophytism and other trophic modes across the family Xylariaceae.


Assuntos
Ecossistema , Endófitos/classificação , Endófitos/fisiologia , Filogenia , Xylariales/classificação , Xylariales/fisiologia , Evolução Biológica , Ecologia , Líquens/microbiologia , Plantas/microbiologia , Estados Unidos
18.
Curr Microbiol ; 72(3): 329-36, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26659835

RESUMO

A new species of Neopestalotiopsis based on both morphological and molecular characteristics is described. Neopestalotiopsis iranensis sp. nov. isolated from rotted strawberry (Fragaria ananassa) fruits as well as from stolon and leaf lesions in Kurdistan province, Iran. Initially, light tan and sunken spots developed on fruits and resulted in a soft decay of the fruit flesh. The new species is morphologically distinguished from similar species with different conidium size and by possessing longer apical appendages, as well as some knobbed basal appendages. Phylogenetic analyses (Bayesian inference, maximum likelihood and maximum parsimony analyses) based on internal transcribed spacer, ß-tubulin, and partial translation elongation factor 1-alpha combined gene sequences also indicated that this species is phylogenetically distinct from others. Moreover, strawberry crop is introduced here as a new host for N. mesopotamica.


Assuntos
Fragaria , Doenças das Plantas/microbiologia , Xylariales/classificação , Xylariales/isolamento & purificação , Análise por Conglomerados , DNA Fúngico/química , DNA Fúngico/genética , DNA de Plantas/química , DNA de Plantas/genética , DNA Espaçador Ribossômico/química , DNA Espaçador Ribossômico/genética , Irã (Geográfico) , Microscopia , Dados de Sequência Molecular , Fator 1 de Elongação de Peptídeos/genética , Filogenia , Análise de Sequência de DNA , Esporos Fúngicos/citologia , Tubulina (Proteína)/genética , Xylariales/citologia , Xylariales/genética
19.
Mycologia ; 107(6): 1304-13, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26354808

RESUMO

This study investigates the diversity and taxonomy of Cryptosphaeria species occurring in the western United States on the basis of morphological characters and multilocus phylogenetic analyses of the ribosomal internal transcribed spacer region, parts of a ß-tubulin gene, the DNA-dependent RNA polymerase II second-largest subunit gene and the nuclear ribosomal large subunit gene. Cryptosphaeria multicontinentalis sp. nov is described from the Sierra Nevada and central coast of California on Populus tremuloides, P. balsamifera subsp. trichocarpa and P. fremontii. Cryptosphaeria pullmanensis is reported from a wide geographic area in the western United States on the main host, P. fremontii. The pathogen C. lignyota is reported for the first time from the Sierra Nevada of California on P. tremuloides. The phylogenetic analyses showed that C. multicontinentalis is a sister species to C. lignyota. Both species were closely related to C. subcutanea and more distantly related to C. pullmanensis. Characteristics of both teleomorph and anamorph of the newly introduced species C. multicontinentalis are described and illustrated.


Assuntos
Filogenia , Doenças das Plantas/microbiologia , Populus/microbiologia , Xylariales/classificação , Xylariales/isolamento & purificação , California , Proteínas Fúngicas/genética , Dados de Sequência Molecular , Tipagem de Sequências Multilocus , Nevada , Fator 1 de Elongação de Peptídeos/genética , RNA Polimerase II/genética , Esporos Fúngicos/classificação , Esporos Fúngicos/genética , Esporos Fúngicos/crescimento & desenvolvimento , Esporos Fúngicos/isolamento & purificação , Tubulina (Proteína)/genética , Xylariales/genética , Xylariales/crescimento & desenvolvimento
20.
Fungal Biol ; 119(5): 348-61, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25937063

RESUMO

Pestalotiopsis-like fungi are an important plant pathogenic genus causing postharvest fruit rot and trunk diseases in grapevine in many countries. Pestalotiopsis-like fungi diseases were studied in vineyards in nine provinces across China. Multi-gene (ITS, ß-tubulin and tef1) analysis coupled with morphology showed that a Neopestalotiopsis sp. and Pestalotiopsis trachicarpicola are associated in causing grapevine fruit rot and trunk diseases in China. Pestalotiopsis trachicarpicola is reported as the causative agent of grapevine diseases in the world for the first time. Neopestalotiopsis sp. caused significantly longer lesions than the other taxon present. This study represents the first attempt to identify and characterize the Pestalotiopsis-like fungi causing grapevine diseases in China using both morphological and molecular approaches.


Assuntos
Doenças das Plantas/microbiologia , Vitis/microbiologia , Xylariales/classificação , Xylariales/isolamento & purificação , China , Proteínas Fúngicas/genética , Dados de Sequência Molecular , Filogenia , Tubulina (Proteína)/genética , Xylariales/genética , Xylariales/crescimento & desenvolvimento
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