Las especies de annulohypoxylon (Hypoxylaceae) de Argentina

Se reconocen once especies de Annulohypoxylon para la Argentina. A. purpureonitens y A. purpureopigmentum se registran por primera vez en el Cono Sur, mientras que A. stygium y A. nitens se citan por primera vez para el noroeste de la Argentina. Se describen los estados asexuales de A. purpuropigmentum y A. subeffusum. Además, se proporcionan una tabla comparativa, una clave para las especies argentinas, fotografías y un mapa con la distribución sudamericana de las especies tratadas aquí.Eleven Annulohypoxylon species are recognized for Argentina. Annulohypoxylon purpureonitens and A. purpureopigmentum are recorded for the first time in the Southern Cone, while A. stygium and A. nitens represent new reports for Northwestern Argentina. Furthermore, the asexual states of A. purpureopigmentum and A. subeffusum are described for the first time. In addition, a comparative table, a key to the Argentinean species, photographs, and a distributional map of these species in South America are provided.Fil: Sir, Esteban Benjamin. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fundación Miguel Lillo; ArgentinaFil: Kuhnert, Eric. Leibniz Universität Hannover, Schneiderberg. Institute for Organic Chemistry; AlemaniaFil: Hladki, Adriana Ines. Fundación Miguel Lillo; ArgentinaFil: Romero, Andrea Irene. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Biodiversidad y Biología Experimental; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; Argentin

Nuevos registros de Hypoxylon (Ascomycota, Hypoxylaceae) para Las Yungas Argentinas

Hypoxylon aeruginosum var. aeruginosum, H. fendleri and H. undulatum collected in the subtropical montane forest from northwest Argentina are reported for the first time for the Southern Cone. We describe and analyze their teleomorph and anamorph, and provide photographs and drawings of the most relevant structures. Moreover, a key to Hypoxylon species so far known from Argentina is given.Como resultado del estudio de especímenes coleccionados en el bosque montano del Noroeste Argentino, se citan por primera vez para el Cono Sur a Hypoxylon aeruginosum var. aeruginosum, H. fendleri y H. undulatum. Se describen y analizan los teleomorfos y anamorfos de esas especies, aportando fotografías y dibujos de las estructuras más relevantes. Además, se proporciona una clave para identificar las especies de Hypoxylon hasta ahora conocidas en Argentina.Fil: Diaz, Sofía M.. Fund.Miguel Lillo. Dir.de Botanica. Laboratorio Criptogámico; ArgentinaFil: Sir, Esteban Benjamin. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Fund.Miguel Lillo. Dir.de Botanica. Laboratorio Criptogámico; ArgentinaFil: Kuhnert, Eric. Leibniz Universitat Hannover; AlemaniaFil: Hladki, Adriana Ines. Fund.Miguel Lillo. Dir.de Botanica. Laboratorio Criptogámico; Argentin

Hypoxylon ochraceotuberosum and Hypoxylon rickii (Ascomycota, Hypoxylaceae) in Las Yungas of Salta province, Northwest of Argentina

Hypoxylon ochraceotuberosum and H. rickii are reported for the first time for the Argentinean funga based on recently collected specimens from the northwestern montane forest. Until now, H. ochraceotuberosum has only been known to occur in the Martinique (French West Indies). In contrast, H. rickii was already recorded for the Southern Cone, but based on specimens collected in the Atlantic Rain Forests from Southeast Brazil. Detailed descriptions and photo illustrations are provided for each species.Hypoxylon ochraceotuberosum y H. rickii se reportan por primera vez para la funga Argentina con base a especímenes coleccionados recientemente en el bosque montano del Noroeste. Hasta ahora, H. ocraceotubeosum solo se conocía de Martinica (French West Indies). En contraste, H. rickii ya estaba reportada para el Cono Sur, pero basado en especímenes coleccionados en la Mata Atlántica del Sureste de Brasil. Se aportan descripciones detalladas e ilustraciones fotográficas para cada especie.Fil: Medina, Patricia del Valle. Fundación Miguel Lillo. Dir.de Botánica. Laboratorio Criptogámico; ArgentinaFil: Kuhnert, Eric. Leibniz Universitat Hannover; AlemaniaFil: Hladki, Adriana Ines. Fundación Miguel Lillo. Dir.de Botánica. Laboratorio Criptogámico; ArgentinaFil: Sir, Esteban Benjamin. Universidad Nacional de Tucumán. Instituto de Bioprospección y Fisiología Vegetal. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet Noa Sur. Instituto de Bioprospección y Fisiología Vegetal; Argentin

Contrasting Effects of Grass - Endophyte Chemotypes on a Tri-Trophic Cascade

Systemic grass-endophytes of the genus Epichloë symbiotically infect the above-ground plant parts of many grass species, where they produce alkaloids in a grass- and endophyte-specific manner that are toxic or deterrent to herbivores. An increasing number of studies show cascading negative effects of endophyte-derived alkaloids that extend to higher trophic levels, harming beneficial insects, including those that control aphid populations. Lacewings are one of the major biological aphid controls, and are especially resistant to insecticides and pollutants, but their susceptibility to endophyte infection in the food chain has never been studied. Our study found variability in aphid population growth depending on the endophyte-grass chemotype, where aphid population growth was lowest on chemotypes known for producing high amounts of loline alkaloids. We also showed that larval and pupal development and mortality of the Common Green Lacewing (Chrysoperla carnea) was, in a non-choice experiment, not affected by endophyte infection in the food chain. This is a first indication that lacewings might be resistant to endophyte-derived alkaloids and could be robust biocontrol agents when applied together with endophyte-infected grass, possibly replacing chemical pesticides.</p

Resurrection and emendation of the Hypoxylaceae, recognised from a multigene phylogeny of the Xylariales

A multigene phylogeny was constructed, including a significant number of representative species of the main lineages in the Xylariaceae and four DNA loci the internal transcribed spacer region (ITS), the large subunit (LSU) of the nuclear rDNA, the second largest subunit of the RNA polymerase II (RPB2), and beta-tubulin (TUB2). Specimens were selected based on more than a decade of intensive morphological and chemotaxonomic work, and cautious taxon sampling was performed to cover the major lineages of the Xylariaceae; however, with emphasis on hypoxyloid species. The comprehensive phylogenetic analysis revealed a clear-cut segregation of the Xylariaceae into several major clades, which was well in accordance with previously established morphological and chemotaxonomic concepts. One of these clades contained Annulohypoxylon, Hypoxylon, Daldinia, and other related genera that have stromatal pigments and a nodulisporium-like anamorph. They are accommodated in the family Hypoxylaceae, which is resurrected and emended. Representatives of genera with a nodulisporium-like anamorph and bipartite stromata, lacking stromatal pigments (i.e. Biscogniauxia, Camillea, and Obolarina) appeared in a clade basal to the xylarioid taxa. As they clustered with Graphostroma platystomum, they are accommodated in the Graphostromataceae. The new genus Jackrogersella with J. multiformis as type species is segregated from Annulohypoxylon. The genus Pyrenopolyporus is resurrected for Hypoxylon polyporus and allied species. The genus Daldinia and its allies Entonaema, Rhopalostroma, Ruwenzoria, and Thamnomyces appeared in two separate subclades, which may warrant further splitting of Daldinia in the future, and even Hypoxylon was divided in several clades. However, more species of these genera need to be studied before a conclusive taxonomic rearrangement can be envisaged. Epitypes were designated for several important species in which living cultures and molecular data are available, in order to stabilise the taxonomy of the Xylariales.Fil: Wendt, Lucile. Helmholtz-Zentrum für Infektionsforschung GmbH. Department of Microbial Drugs; Alemania. German Centre for Infection Research; AlemaniaFil: Sir, Esteban Benjamin. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Unidad Ejecutora Lillo. Fundación Miguel Lillo. Unidad Ejecutora Lillo; ArgentinaFil: Kuhnert, Eric. Helmholtz-Zentrum für Infektionsforschung GmbH. Department of Microbial Drugs; Alemania. German Centre for Infection Research; AlemaniaFil: Heitkämper, Simone. Helmholtz-Zentrum für Infektionsforschung GmbH. Department of Microbial Drugs; Alemania. German Centre for Infection Research; AlemaniaFil: Lambert, Christopher. Helmholtz-Zentrum für Infektionsforschung GmbH. Department of Microbial Drugs; Alemania. German Centre for Infection Research; AlemaniaFil: Hladki, Adriana I.. Fundación Miguel Lillo. Dirección de Botánica. Instituto de Micologia; ArgentinaFil: Romero, Andrea Irene. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Micología y Botánica. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Micología y Botánica; ArgentinaFil: Luangsa-Ard, Janet Jennifer. National Center for Genetic Engineering and Biotechnology; TailandiaFil: Srikitikulchai, Prasert. National Center for Genetic Engineering and Biotechnology; TailandiaFil: Peršoh, Derek. Ruhr-Universität Bochum; AlemaniaFil: Stadler, Marc. Helmholtz-Zentrum für Infektionsforschung GmbH. Department of Microbial Drugs; Alemania. German Centre for Infection Research; Alemani

Cytotoxic and Pathogenic Properties of Klebsiella oxytoca Isolated from Laboratory Animals

Klebsiella oxytoca is an opportunistic pathogen implicated in various clinical diseases in animals and humans. Studies suggest that in humans K. oxytoca exerts its pathogenicity in part through a cytotoxin. However, cytotoxin production in animal isolates of K. oxytoca and its pathogenic properties have not been characterized. Furthermore, neither the identity of the toxin nor a complete repertoire of genes involved in K. oxytoca pathogenesis have been fully elucidated. Here, we showed that several animal isolates of K. oxytoca, including the clinical isolates, produced secreted products in bacterial culture supernatant that display cytotoxicity on HEp-2 and HeLa cells, indicating the ability to produce cytotoxin. Cytotoxin production appears to be regulated by the environment, and soy based product was found to have a strong toxin induction property. The toxin was identified, by liquid chromatography-mass spectrometry and NMR spectroscopy, as low molecular weight heat labile benzodiazepine, tilivalline, previously shown to cause cytotoxicity in several cell lines, including mouse L1210 leukemic cells. Genome sequencing and analyses of a cytotoxin positive K. oxytoca strain isolated from an abscess of a mouse, identified genes previously shown to promote pathogenesis in other enteric bacterial pathogens including ecotin, several genes encoding for type IV and type VI secretion systems, and proteins that show sequence similarity to known bacterial toxins including cholera toxin. To our knowledge, these results demonstrate for the first time, that animal isolates of K. oxytoca, produces a cytotoxin, and that cytotoxin production is under strict environmental regulation. We also confirmed tilivalline as the cytotoxin present in animal K. oxytoca strains. These findings, along with the discovery of a repertoire of genes with virulence potential, provide important insights into the pathogenesis of K. oxytoca. As a novel diagnostic tool, tilivalline may serve as a biomarker for K oxytoca-induced cytotoxicity in humans and animals through detection in various samples from food to diseased samples using LC-MS/MS. Induction of K. oxytoca cytotoxin by consumption of soy may be in part involved in the pathogenesis of gastrointestinal disease

A genomic journey in the secondary metabolite diversity of fungal plant and insect pathogens: from functional to population genomics

Fungal pathogens produce a broad array of secondary metabolites (SMs), which allow the fungus to thrive in its natural habitat and gain competitive advantage. Analysis of the genetically encoded blueprints for SM assembly highlighted that only a small portion of the SMs these fungi are capable of producing are known, and even fewer have been investigated for their natural function. Using molecular tools, a lot of progress has been made recently in identifying the blueprint products and linking them to their ecological purpose such as the peptide virulence factor fusaoctaxin A released by Fusarium graminearum during infection of wheat or the F. oxysporum polyketide bikaverin that provides competitive advantage against bacteria in tomato. In addition, population genomics have given particularly important insights into the species-specific plasticity of the SM blueprint arsenal, showcasing the ongoing evolution and adaptation of fungal pathogens. This approach holds promise in inferring roles in pathogenicity of many more fungal SMs

Silphiperfolene-Type Terpenoids and Other Metabolites from Cultures of the Tropical Ascomycete Hypoxylon rickii (Xylariaceae).

A culture isolated from ascospores of Hypoxylon rickii, a xylariaceous ascomycete collected in Martinique, had yielded botryane, noreremophilane and abietane-type terpenoids in a preceding study, but additional metabolites were detected by extensive HPLC-MS analysis in other fractions. Herein we report the further isolation of four new sesquiterpenoids with a silphiperfol-6-ene skeleton from extracts of H. rickii. The planar structures were elucidated by NMR and HRMS data as 13-hydroxysilphiperfol-6-ene (1), 9-hydroxysilphiperfol-6-en-13-oic acid (2), 2-hydroxysilphiperfol-6-en-13-oic acid (3) and 15-hydroxysilphiperfol-6-en-13-oic acid (4). For compounds 2-4 we propose the trivial names rickinic acids A-C. Their stereochemistry was assigned by ROESY correlations as well as by the specific optical rotation. Additionally, the known compounds, botryenanol, dehydrobotrydienol, cyclo(Phe-Pro), cyclo(Pro-Leu), (+)-ramulosin and α-eleostearic acid were isolated. The antimicrobial and cytotoxic activities of the new compounds are also reported

Rickicaryophyllane A, a Caryophyllane from the Ascomyceteous Fungus Hypoxylon rickii and a 10-Norbotryane Congener.

Herein we report the isolation from Hypoxylon rickii of a new sesquiterpenoid (1) with a caryophyllane skeleton. The planar structure of 1 was elucidat ed by NMR and HRMS data as the 1,12-dihydro-l-hydroxyl derivative of caryophyllenol-I, for which we propose the name rickicaryophyllane A. Its relative stereochemistry was assigned with a series of ID NOESY experiments, while the IR,2S,5R,9R absolute configuration was demonstrated by Mosher's analysis. Besides, we isolated 3-(hydroxymethyl)-1,1,3,5-tetramethyl-1,2,3,5,6,7-hexahydro-4H-inden-4-one (2) as a new 10-norbotryane derivative and the known metabolite orcacetophenone (3)