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1.
MycoKeys ; 95: 131-162, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37251992

RESUMEN

During a mycological survey of the Democratic Republic of the Congo, a fungal specimen that morphologically resembled the American species Hypoxylonpapillatum was encountered. A polyphasic approach including morphological and chemotaxonomic together with a multigene phylogenetic study (ITS, LSU, tub2, and rpb2) of Hypoxylon spp. and representatives of related genera revealed that this strain represents a new species of the Hypoxylaceae. However, the multi-locus phylogenetic inference indicated that the new fungus clustered with H.papillatum in a separate clade from the other species of Hypoxylon. Studies by ultrahigh performance liquid chromatography coupled to diode array detection and ion mobility tandem mass spectrometry (UHPLC-DAD-IM-MS/MS) were carried out on the stromatal extracts. In particular, the MS/MS spectra of the major stromatal metabolites of these species indicated the production of hitherto unreported azaphilone pigments with a similar core scaffold to the cohaerin-type metabolites, which are exclusively found in the Hypoxylaceae. Based on these results, the new genus Parahypoxylon is introduced herein. Aside from P.papillatum, the genus also includes P.ruwenzoriensesp. nov., which clustered together with the type species within a basal clade of the Hypoxylaceae together with its sister genus Durotheca.

2.
MycoKeys ; 72: 17-42, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32963487

RESUMEN

Thailand is known to be a part of what is called the Indo-Burma biodiversity hotspot, hosting a vast array of organisms across its diverse ecosystems. This is reflected by the increasing number of new species described over time, especially fungi. However, a very few fungal species from the specialized spider-parasitic genus Gibellula have ever been reported from this region. A survey of invertebrate-pathogenic fungi in Thailand over several decades has led to the discovery of a number of fungal specimens with affinities to this genus. Integration of morphological traits into multi-locus phylogenetic analysis uncovered four new species: G. cebrennini, G. fusiformispora, G. pigmentosinum, and G. scorpioides. All these appear to be exclusively linked with torrubiella-like sexual morphs with the presence of granulomanus-like asexual morph in G. pigmentosinum and G. cebrennini. A remarkably high host specificity of these new species towards their spider hosts was revealed, and for the first time, evidence is presented for manipulation of host behavior in G. scorpioides.

3.
J Fungi (Basel) ; 6(3)2020 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-32842463

RESUMEN

The genus Stromatoneurospora was erected in 1973 by Jong and Davis to accommodate the pyrophilic pyrenomycete Sphaeria phoenix and has traditionally been placed in the family Xylariaceae based on morphological features. However, no living culture of this genus has so far been available in the public domain. Molecular data were restricted to an internal transcribed spacer (ITS) sequence that only confirmed the familial position, and was generated from a strain that is not deposited in a public culture collection. We have recently collected fresh material and were able to culture this fungus from Thailand. The secondary metabolites of this strains were analysed after fermentation in multiple media. The the prominent components of these fermentation were purified, using preparative chromatography. Aside from two new eremophilane sesquiterpenoids named phoenixilanes A-B (1-2), four other components that are known from species of the xylariaceous genera Xylaria and Poronia were identified by spectral methods (nuclear magnetic resonance spectroscopy and high resolution mass spectrometry). Notably, (-)-(R)-6-hydroxy-3-methyl-4-dihydroisocoumarin-5-carboxylic acid (6) has not been reported as a natural product before. Moreover, DNA sequences of Stromatoneurospora phoenix clustered with members of the genera Poronia and Podosordaria in a multi-locus molecular phylogeny. These results confirmed that the genus belongs to the same evolutionary lineage as the coprophilic Xylariaceae. The results also suggest that this lineage has evolved independently from the plant-inhabiting saprotrophs and endophytes that are closely related to the genus Xylaria. These findings are discussed in relation to some theories about the endophytic vs. the pyrophilic/coprophilic fungal life style.

4.
MycoKeys ; 71: 1-22, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32831550

RESUMEN

Akanthomyces is a genus of invertebrate-pathogenic fungi from the family Cordycipitaceae (Ascomycota, Hypocreales). Its species occurs on two different types of hosts, spiders and insects, and in the latter case specifically Lepidoptera adults. Three new species of Akanthomyces, A. noctuidarum, A. pyralidarum, and A. tortricidarum occurring on adult moths from Thailand are proposed based on the differences of their morphological characteristics and molecular data. Phylogenetic analyses using a combined dataset, including the internal transcribed spacer regions, the large subunit of the ribosomal DNA, translation elongation factor 1-α, the largest subunit of RNA polymerase II, and the second largest subunit of RNA polymerase II, support the delimitation of these new species in Akanthomyces.

5.
Biomolecules ; 10(5)2020 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-32456162

RESUMEN

During the course of our search for novel biologically active metabolites from tropical fungi, we are using chemotaxonomic and taxonomic methodology for the preselection of interesting materials. Recently, three previously undescribed benzo[j]fluoranthenes (1-3) together with the known derivatives truncatones A and C (4, 5) were isolated from the stromata of the recently described species Annulohypoxylon viridistratum collected in Thailand. Their chemical structures were elucidated by means of spectral methods, including nuclear magnetic resonance (NMR) spectroscopy and high-resolution mass spectrometry (HR-MS). The new compounds, for which we propose the trivial names viridistratins A-C, exhibited weak-to-moderate antimicrobial and cytotoxic activities in cell-based assays.


Asunto(s)
Antiinfecciosos/química , Ascomicetos/química , Fluorenos/química , Animales , Antiinfecciosos/toxicidad , Bacterias/efectos de los fármacos , Línea Celular , Fibroblastos/efectos de los fármacos , Fluorenos/toxicidad , Concentración 50 Inhibidora , Ratones , Levaduras/efectos de los fármacos
6.
Biomolecules ; 9(2)2019 02 19.
Artículo en Inglés | MEDLINE | ID: mdl-30791504

RESUMEN

In our ongoing search for new bioactive fungal metabolites, two new cytochalasans were isolated from stromata of the hypoxylaceous ascomycete Hypoxylon fragiforme. Their structures were elucidated via high-resolution mass spectrometry (HR-MS) and nuclear magnetic resonance (NMR) spectroscopy. Together with 23 additional cytochalasans isolated from ascomata and mycelial cultures of different Ascomycota, they were tested on their ability to disrupt the actin cytoskeleton of mammal cells in a preliminary structure⁻activity relationship study. Out of all structural features, the presence of hydroxyl group at the C7 and C18 residues, as well as their stereochemistry, were determined as important factors affecting the potential to disrupt the actin cytoskeleton. Moreover, reversibility of the actin disrupting effects was tested, revealing no direct correlations between potency and reversibility in the tested compound group. Since the diverse bioactivity of cytochalasans is interesting for various applications in eukaryotes, the exact effect on eukaryotic cells will need to be determined, e.g., by follow-up studies involving medicinal chemistry and by inclusion of additional natural cytochalasans. The results are also discussed in relation to previous studies in the literature, including a recent report on the anti-Biofilm activities of essentially the same panel of compounds against the pathogenic bacterium, Staphylococcus aureus.


Asunto(s)
Citoesqueleto de Actina/efectos de los fármacos , Citocalasinas/química , Citocalasinas/farmacología , Células Eucariotas/efectos de los fármacos , Citoesqueleto de Actina/metabolismo , Citocalasinas/aislamiento & purificación , Células Eucariotas/metabolismo , Humanos , Conformación Molecular , Relación Estructura-Actividad , Células Tumorales Cultivadas
7.
Sci Rep ; 8(1): 18087, 2018 12 27.
Artículo en Inglés | MEDLINE | ID: mdl-30591711

RESUMEN

Polycephalomyces (Ophiocordycipitaceae) species are found in subtropical regions and are parasitic or hyperparasitic on insects. Two new species, P. aurantiacus and P. marginaliradians, parasitic on Ophiocordyceps barnesii and larva of Cossidae respectively, are introduced in this paper. Morphological comparison with extant species and DNA based phylogenies from analyses of a multigene dataset support the establishment of the new taxa. Polycephalomyces aurantiacus, exhibiting a hyperparasitic lifestyle on Ophiocordyceps barnesii, differs from other species in producing orange conidia in mass and have longer ß-phialides in culture. Polycephalomyces marginaliradians differs from other Ophiocordyceps species by producing single stromata with a stipe, smaller perithecia and branched α-phialides and catenate α-conidia and is parasitic on Cossidae. A combined nrSSU, nrLSU, ITS, tef-1a, rpb1 and rpb2 sequence data was analysed phylogenetically including Ophiocordyceps and Polycephalomyces taxa. The new species described herein are clearly distinct from other species in Polycephalomyces. We provide a key to the species of Polycephalomyces and discuss relevant interspecies relationships.


Asunto(s)
Genes Fúngicos , Hypocreales/clasificación , Hypocreales/genética , Familia de Multigenes , Filogenia , Hypocreales/crecimiento & desarrollo , Tailandia
8.
IMA Fungus ; 8(2): 335-353, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-29242779

RESUMEN

The ending of dual nomenclatural systems for pleomorphic fungi in 2011 requires the reconciliation of competing names, ideally linked through culture based or molecular methods. The phylogenetic systematics of Hypocreales and its many genera have received extensive study in the last two decades, however resolution of competing names in Cordycipitaceae has not yet been addressed. Here we present a molecular phylogenetic investigation of Cordycipitaceae that enables identification of competing names in this family, and provides the basis upon which these names can be maintained or suppressed. The taxonomy presented here seeks to harmonize competing names by principles of priority, recognition of monophyletic groups, and the practical usage of affected taxa. In total, we propose maintaining nine generic names, Akanthomyces, Ascopolyporus, Beauveria, Cordyceps, Engyodontium, Gibellula, Hyperdermium, Parengyodontium, and Simplicillium and the rejection of eight generic names, Evlachovaea, Granulomanus, Isaria, Lecanicillium, Microhilum, Phytocordyceps, Synsterigmatocystis, and Torrubiella. Two new generic names, Hevansia and Blackwellomyces, and a new species, Beauveria blattidicola, are described. New combinations are also proposed in the genera Akanthomyces, Beauveria, Blackwellomyces, and Hevansia.

9.
IMA Fungus ; 6(2): 357-62, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26734546

RESUMEN

Based on the taxonomic and nomenclatural recommendations of Quandt et al. (2014) new species combinations are made for Ophiocordycipitaceae. These new combinations are compliant with recent changes in the International Code of Nomenclature for algae, fungi, and plants (ICN) and the abolition of the dual system of nomenclature for fungi. These changes include 10 new combinations into Drechmeria, four new combinations into Harposporium, 23 new combinations and 15 synonymies in Ophiocordyceps, and one new combination into Purpureocillium.

10.
IMA Fungus ; 5(1): 121-34, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25083412

RESUMEN

Ophiocordycipitaceae is a diverse family comprising ecologically, economically, medicinally, and culturally important fungi. The family was recognized due to the polyphyly of the genus Cordyceps and the broad diversity of the mostly arthropod-pathogenic lineages of Hypocreales. The other two cordyceps-like families, Cordycipitaceae and Clavicipitaceae, will be revised taxonomically elsewhere. Historically, many species were placed in Cordyceps, but other genera have been described in this family as well, including several based on anamorphic features. Currently there are 24 generic names in use across both asexual and sexual life stages for species of Ophiocordycipitaceae. To reflect changes in Art. 59 in the International Code of Nomenclature for algae, fungi, and plants (ICN), we propose to protect and to suppress names within Ophiocordycipitaceae, and to present taxonomic revisions in the genus Tolypocladium, based on rigorous and extensively sampled molecular phylogenetic analyses. When approaching this task, we considered the principles of priority, monophyly, minimizing taxonomic revisions, and the practical utility of these fungi within the wider biological research community.

11.
IMA Fungus ; 4(1): 57-69, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23898413

RESUMEN

The genus Durotheca is introduced with D. depressa sp. nov., as type. Hypoxylon comedens is transferred to Durotheca, based on its morphology with further evidence from molecular phylogenetic studies; a combined ß-tubulin and α-actin gene dataset. Theissenia cinerea is synonymized with D. comedens, and the type of Theissenia, T. pyrenocrata, is shown to occupy a basal, rather distant position in a monotypic clade in relation to sequenced taxa of Durotheca. This clade has an unresolved position in relation to the two informal subfamilies "Xylarioideae" and "Hypoxyloideae" within the Xylariaceae. New distributional data for D. comedens and T. pyrenocrata are presented, with the former found to be widespread in South-East Asia and the latter is reported as new from western Amazonia (Ecuador). One further species described in Theissenia, T. rogersii, is transferred to Durotheca, whilst T. eurima is accepted in Theissenia.

12.
J Nat Prod ; 74(10): 2143-50, 2011 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-21995505

RESUMEN

Seven new lanostane-type triterpenes, hypocrellols A-G (1-7), and six new hopane-type triterpenes, 7ß,15α-dihydroxy-22(29)-hopene (8), 3ß,7ß-dihydroxy-22(29)-hopene (9), 3ß-acetoxy-15α-hydroxy-22(29)-hopene (10), 3ß,7ß,15α,22-tetrahydroxyhopane (11), 3ß-acetoxy-7ß,15α,22-trihydroxyhopane (12), and 7ß,15α,22-trihydroxyhopane (13), were isolated from the scale insect pathogenic fungus Hypocrella sp. BCC 14524. The structures of the new compounds were elucidated by analyses of the NMR spectroscopic and mass spectrometry data. The structure of 1 was confirmed by X-ray crystallography.


Asunto(s)
Antimaláricos/aislamiento & purificación , Antineoplásicos/aislamiento & purificación , Antituberculosos/aislamiento & purificación , Hypocreales/química , Triterpenos/aislamiento & purificación , Animales , Antimaláricos/química , Antimaláricos/farmacología , Antineoplásicos/química , Antineoplásicos/farmacología , Antituberculosos/química , Antituberculosos/farmacología , Chlorocebus aethiops , Cristalografía por Rayos X , Resistencia a Medicamentos , Ensayos de Selección de Medicamentos Antitumorales , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Mycobacterium tuberculosis/efectos de los fármacos , Resonancia Magnética Nuclear Biomolecular , Plasmodium falciparum/efectos de los fármacos , Estereoisomerismo , Tailandia , Triterpenos/química , Triterpenos/farmacología , Células Vero
13.
Fungal Biol ; 115(7): 608-14, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21724166

RESUMEN

Several fungal pathogens of ants have been reported as members of the family Ophiocordycipitaceae in the order Hypocreales. Surveys in the south of Thailand have shown specimens showing characteristics that are morphologically similar to Ophiocordyceps unilateralis, a very common ant pathogen, by producing a lateral pad on one side of the stroma and producing whole ascospores. Phylogenetic analyses of the partial elongation factor tef1-α and the internal transcribed spacer regions ITS1-5.8S-ITS2 rDNA have shown that this is a distinct species from O. unilateralis. The morphological characters of Ophiocordyceps halabalaensis differs from O. unilateralis in the possession of bigger perithecia and ascospores, and molecular analyses have shown that this ant-specific fungus is sufficiently different from O. unilateralis, deserving the naming of a new species. Aspects of morphology, host association/host-specificity, and taxonomic position are discussed.


Asunto(s)
Hormigas/microbiología , Hypocreales/clasificación , Hypocreales/aislamiento & purificación , Animales , ADN de Hongos/genética , Proteínas Fúngicas/genética , Hypocreales/genética , Datos de Secuencia Molecular , Filogenia , Esporas Fúngicas/genética , Tailandia
15.
Mycologia ; 103(5): 1055-73, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21482632

RESUMEN

Beauveria is a cosmopolitan anamorphic genus of arthropod pathogens that includes the agronomically important species, B. bassiana and B. brongniartii, which are used as mycoinsecticides for the biological control of pest insects. Recent phylogenetic evidence demonstrates that Beauveria is monophyletic within the Cordycipitaceae (Hypocreales), and both B. bassiana and B. brongniartii have been linked developmentally and phylogenetically to Cordyceps species. Despite recent interest in the genetic diversity and molecular ecology of Beauveria, particularly as it relates to their role as pathogens of insects in natural and agricultural environments, the genus has not received critical taxonomic review for several decades. A multilocus phylogeny of Beauveria based on partial sequences of RPB1, RPB2, TEF and the nuclear intergenic region, Bloc, is presented and used to assess diversity within the genus and to evaluate species concepts and their taxonomic status. B. bassiana and B. brongniartii, both which represent species complexes and which heretofore have lacked type specimens, are redescribed and types are proposed. In addition six new species are described including B. varroae and B. kipukae, which form a biphyletic, morphologically cryptic sister lineage to B. bassiana, B. pseudobassiana, which also is morphologically similar to but phylogenetically distant from B. bassiana, B. asiatica and B. australis, which are sister lineages to B. brongniartii, and B. sungii, an Asian species that is linked to an undetermined species of Cordyceps. The combination B. amorpha is validly published and an epitype is designated.


Asunto(s)
Artrópodos/microbiología , Beauveria/clasificación , Beauveria/genética , ADN de Hongos/genética , Animales , Secuencia de Bases , Beauveria/patogenicidad , ADN de Hongos/análisis , ADN Espaciador Ribosómico/genética , Factores Eucarióticos de Iniciación , Variación Genética , Control Biológico de Vectores , Filogenia , Reacción en Cadena de la Polimerasa , ARN Polimerasa II/genética , Análisis de Secuencia de ADN
16.
J Nat Prod ; 74(4): 782-9, 2011 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-21473608
17.
Fungal Biol ; 114(9): 739-45, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20943183

RESUMEN

A hypocrealean Coleoptera pathogen with characteristic part-spores, collected from Khao Yai National Park and Kaeng Krachan National Park in Thailand, is reported. The overall morphology was similar to Cordyceps barnesii, which is known from Sri Lanka, with ascospores disarticulating into four unusually long part-spores that were 30-40 µm long. This disarticulation and part-spore size is, so far, unique within Cordyceps sensu lato. The Thai material was identified with C. barnesii and its placement in the genus Ophiocordyceps was confirmed. Multigene analyses based on the ribosomal small subunit, RPB1 and RPB2 genes revealed the close relationship of the Thai material to Ophiocordyceps konnoana as well as O. ravenelii, O. superficialis, and O. nigrella (all of which have significantly smaller part-spores). However, Ophiocordyceps barnesii and these related species were all characterised by dark-brown to purplish stromata and an affinity for melolonthid larval hosts. No anamorph was seen in the field and was not produced in the slow-growing cultures.


Asunto(s)
Escarabajos/microbiología , Hypocreales/clasificación , Hypocreales/aislamiento & purificación , Animales , Proteínas Fúngicas/genética , Hypocreales/citología , Hypocreales/genética , Datos de Secuencia Molecular , Filogenia , Esporas Fúngicas/clasificación , Esporas Fúngicas/citología , Esporas Fúngicas/genética , Esporas Fúngicas/aislamiento & purificación , Tailandia
18.
Mycol Res ; 113(Pt 12): 1389-95, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19766720

RESUMEN

Beauvericin is a naturally occurring cyclohexadepsipeptide originally described from Beauveria bassiana but also reported from several Fusarium species as well as members of the genus Isaria. Twenty-six isolates of Isaria species and its Cordyceps teleomorph, and ten taxonomically close strains including Beauveria, Nomuraea and Paecilomyces species were sequenced and tested for beauvericin production. Trees using ITS rDNA and beta-tubulin sequence data were constructed and used to infer the phylogenetic distribution of beauvericin production. A group comprising Isaria tenuipes and its known teleomorph Cordyceps takaomontana, Isaria cicadae and its Cordyceps teleomorph, Isaria japonica and Isaria fumosorosea, showed positive beauvericin production which correlated well with combined ITS rDNA and beta-tubulin phylogenies. The results suggested that beauvericin can serve as a chemotaxonomic marker for these limited species of the I. tenuipes complex.


Asunto(s)
Depsipéptidos/biosíntesis , Hypocreales/clasificación , Beauveria/genética , Cordyceps/genética , Elementos Transponibles de ADN , ADN de Hongos/genética , ADN Ribosómico/genética , Fusarium/clasificación , Fusarium/genética , Genes del Tipo Sexual de los Hongos , Hypocreales/genética , Hypocreales/metabolismo , Técnicas de Tipificación Micológica , Paecilomyces/clasificación , Paecilomyces/genética , Filogenia , Microbiología del Suelo , Especificidad de la Especie , Tubulina (Proteína)/genética , Factores de Virulencia/genética
19.
Mycol Res ; 113(Pt 6-7): 684-99, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19249367

RESUMEN

A combined ITS and beta-tubulin gene phylogeny has revealed new species of Hypocrella and Aschersonia related to the type species Hypocrella discoidea from natural forest in Thailand. As a result, Hypocrella calendulina and Hypocrella luteola are named as new species with Aschersonia sensu stricto anamorphs for specimens previously identified as Hypocrella discoidea sensu Petch. Hypocrella siamensis and Aschersonia minutispora are described as new species, both exhibiting brown stromata, with the former producing whole ascospores.


Asunto(s)
ADN Espaciador Ribosómico/genética , Proteínas Fúngicas/genética , Hypocreales/clasificación , Filogenia , Esporas Fúngicas/citología , Tubulina (Proteína)/genética , ADN de Hongos/genética , Hypocreales/citología , Hypocreales/genética , Hypocreales/aislamiento & purificación , Datos de Secuencia Molecular , Esporas Fúngicas/clasificación , Esporas Fúngicas/genética , Esporas Fúngicas/aislamiento & purificación , Tailandia , Árboles/microbiología
20.
Mycol Res ; 113(Pt 3): 279-89, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18938242

RESUMEN

Torrubiella is a genus of arthropod-pathogenic fungi that primarily attacks spiders and scale insects. Based on the morphology of the perithecia, asci, and ascospores, it is classified in Clavicipitaceae s. lat. (Hypocreales), and is considered a close relative of Cordyceps s. 1., which was recently reclassified into three families (Clavicipitaceae s. str., Cordycipitaceae, Ophiocordycipitaceae) and four genera (Cordyceps s. str, Elaphocordyceps, Metacordyceps, and Ophiocordyceps). Torrubiella is distinguished morphologically from Cordyceps s. lat. mainly by the production of superficial perithecia and the absence of a well-developed stipitate stroma. To test and refine evolutionary hypotheses regarding the placement of Torrubiella and its relationship to Cordyceps s. lat., a multi-gene phylogeny was constructed by conducting ML and Bayesian analyses. The monophyly of Torrubiella was rejected by these analyses with species of the genus present in Clavicipitaceae, Cordycipitaceae, and Ophiocordycipitaceae, and often intermixed among species of Cordyceps s. lat. The morphological characters traditionally used to define the genus are, therefore, not phylogenetically informative, with the stipitate stromata being gained and/or lost several times among clavicipitaceous fungi. Two new genera (Conoideocrella, Orbiocrella) are proposed to accommodate two separate lineages of torrubielloid fungi in the Clavicipitaceae s. str. In addition, one species is reclassified in Cordyceps s. str. and three are reclassified in Ophiocordyceps. The phylogenetic importance of anamorphic genera, host affiliation, and stipitate stromata is discussed.


Asunto(s)
Evolución Biológica , Hypocreales/clasificación , Animales , ADN de Hongos/genética , Hypocreales/genética , Filogenia , Arañas/microbiología
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