• Labyrinthopeptins as virolytic inhibitors of respiratory syncytial virus cell entry.

      Blockus, Sebastian; Sake, Svenja M; Wetzke, Martin; Grethe, Christina; Graalmann, Theresa; Pils, Marina; Le Goffic, Ronan; Galloux, Marie; Prochnow, Hans; Rox, Katharina; et al. (Elsevier, 2020-03-18)
      Acute lower respiratory tract infections (ALRI) caused by respiratory syncytial virus (RSV) are associated with a severe disease burden among infants and elderly patients. Treatment options are limited. While numerous drug candidates with different viral targets are under development, the utility of RSV entry inhibitors is challenged by a low resistance barrier and by single mutations causing cross-resistance against a wide spectrum of fusion inhibitor chemotypes. We developed a cell-based screening assay for discovery of compounds inhibiting infection with primary RSV isolates. Using this system, we identified labyrinthopeptin A1 and A2 (Laby A1/A2), lantibiotics isolated from Actinomadura namibiensis, as effective RSV cell entry inhibitors with IC50s of 0.39 μM and 4.97 μM, respectively, and with favourable therapeutic index (>200 and > 20, respectively). Both molecules were active against multiple RSV strains including primary isolates and their antiviral activity against RSV was confirmed in primary human airway cells ex vivo and a murine model in vivo. Laby A1/A2 were antiviral in prophylactic and therapeutic treatment regimens and displayed synergistic activity when applied in combination with each other. Mechanistic studies showed that Laby A1/A2 exert virolytic activity likely by binding to phosphatidylethanolamine moieties within the viral membrane and by disrupting virus particle membrane integrity. Probably due to its specific mode of action, Laby A1/A2 antiviral activity was not affected by common resistance mutations to known RSV entry inhibitors. Taken together, Laby A1/A2 represent promising candidates for development as RSV inhibitors. Moreover, the cell-based screening system with primary RSV isolates described here should be useful to identify further antiviral agents.
    • Labyrinthopeptins exert broad-spectrum antiviral activity through lipid-binding-mediated virolysis.

      Prochnow, Hans; Rox, Katharina; Birudukota, N V Suryanarayana; Weichert, Loreen; Hotop, Sven-Kevin; Klahn, Philipp; Mohr, Kathrin; Franz, Sergej; Banda, Dominic H; Blockus, Sebastian; et al. (ASM, 2019-10-30)
      To counteract the serious health threat posed by known and novel viral pathogens, drugs that target a variety of viruses through a common mechanism have attracted recent attention due to their potential in treating (re-)emerging infections, for which direct acting antivirals are not available. We found that labyrinthopeptins A1 and A2, the prototype congeners of carbacyclic lanthipeptides, inhibit the proliferation of diverse enveloped viruses, including Dengue virus, Zika virus, West Nile virus, Hepatitis C virus, Chikungunya virus, Karposi's Sarcoma-associated Herpes virus, Cytomegalovirus, and Herpes Simplex virus, in the low μM to nM range. Mechanistic studies on viral particles revealed that labyrinthopeptins induce a virolytic effect through binding to the viral membrane lipid phosphatidylethanolamine (PE). These effects are enhanced by a combined equimolar application of both labyrinthopeptins, and a clear synergism was observed across a concentration range corresponding to IC10-IC90 values of the compounds. Time-resolved experiments with large unilamellar vesicles (LUVs) reveal that membrane lipid raft compositions (PC/PE/Chol/SM (17:10:33:40)) are particularly sensitive to labyrinthopeptins compared to PC/PE (90:10) LUVs, even though the overall PE-amount remains constant. Labyrinthopeptins exhibited low cytotoxicity and had favorable pharmacokinetic properties in mice (t1/2= 10.0 h), which designates them as promising antiviral compounds acting by an unusual viral lipid targeting mechanism.Importance For many viral infections, current treatment options are insufficient. Because the development of each antiviral drug is time-consuming and expensive, the prospect of finding broad-spectrum antivirals that can fight multiple, diverse viruses - well-known as well as (re-)emerging species - has gained attention, especially for the treatment of viral co-infections. While most known broad spectrum agents address processes in the host cell, we found that targeting lipids of the free virus outside the host cell with the natural products labyrinthopeptin A1 and A2 is a viable strategy to inhibit the proliferation of a broad range of viruses from different families, including Chikungunya virus, Dengue virus, Zika virus, Karposi's Sarcoma-associated Herpes virus, or Cytomegalovirus. Labyrinthopeptins bind to viral phosphatidylethanolamine and induce virolysis without exerting cytotoxicity to host cells. This represents a novel and unusual mechanism to tackle medically relevant viral infections.
    • Lanyamycin, a macrolide antibiotic from Sorangium cellulosum, strain Soce 481 (Myxobacteria)

      Mulwa, Lucky S.; Jansen, Rolf; Praditya, Dimas F.; Mohr, Kathrin I.; Okanya, Patrick W.; Wink, Joachim; Steinmann, Eike; Stadler, Marc; HZI,Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7,38124 Braunschweig, Germany. (Beilstein-Institut, 2018-06-26)
      Lanyamycin (1/2), a secondary metabolite occurring as two epimers, was isolated from the myxobacterium Sorangium cellulosum, strain Soce 481. The structures of both epimers were elucidated from HRESIMS and 1D and 2D NMR data and the relative configuration of their macrolactone ring was assigned based on NOE and vicinal 1H NMR coupling constants and by calculation of a 3D model. Lanyamycin inhibited HCV infection into mammalian liver cells with an IC50 value of 11.8 µM, and exhibited a moderate cytotoxic activity against the mouse fibroblast cell line L929 and the human nasopharyngeal cell line KB3 with IC50 values of 3.1 and 1.5 μM, respectively, and also suppressed the growth of the Gram-positive bacterium Micrococcus luteus.
    • Large Scale Production and Downstream Processing of Labyrinthopeptins from the Actinobacterium .

      Rupcic, Zeljka; Hüttel, Stephan; Bernecker, Steffen; Kanaki, Sae; Stadler, Marc; Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7, 38124 Braunschweig, Germany. (2018-06-05)
      A method was established for the production of 1.2-fold and 4.2-fold increased amounts of the antiviral and central nervous system-active lantipeptides, labyrinthopeptins A1 and A2, respectively, isolated from the actinobacterium
    • Lentinulactam, a hirsutane sesquiterpene with an unprecedented lactam modification

      Helaly, Soleiman E.; Richter, Christian; Thongbai, Benjarong; Hyde, Kevin D.; Stadler, Marc; Helmholtz Centre for infection research, Inhoffenstr. 7, 38124 Braunschweig, Germany. (2016-12)
    • Microfungi associated with Clematis (Ranunculaceae) with an integrated approach to delimiting species boundaries

      Phukhamsakda, Chayanard; McKenzie, Eric H. C.; Phillips, Alan J. L.; Gareth Jones, E. B.; Jayarama Bhat, D.; Stadler, Marc; Bhunjun, Chitrabhanu S.; Wanasinghe, Dhanushka N.; Thongbai, Benjarong; Camporesi, Erio; et al. (Springer Science and Business Media LLC, 2020-07-07)
      The cosmopolitan plant genus Clematis contains many climbing species that can be found worldwide. The genus occurs in the wild and is grown commercially for horticulture. Microfungi on Clematis were collected from Belgium, China, Italy, Thailand and the UK. They are characterized by morphology and analyses of gene sequence data using an integrated species concept to validate identifications. The study revealed two new families, 12 new genera, 50 new species, 26 new host records with one dimorphic character report, and ten species are transferred to other genera. The new families revealed by multigene phylogeny are Longiostiolaceae and Pseudomassarinaceae in Pleosporales (Dothideomycetes). New genera are Anthodidymella (Didymellaceae), Anthosulcatispora and Parasulcatispora (Sulcatisporaceae), Fusiformispora (Amniculicolaceae), Longispora (Phaeosphaeriaceae), Neobyssosphaeria (Melanommataceae), Neoleptosporella (Chaetosphaeriales, genera incertae sedis), Neostictis (Stictidaceae), Pseudohelminthosporium (Neomassarinaceae), Pseudomassarina (Pseudomassarinaceae), Sclerenchymomyces (Leptosphaeriaceae) and Xenoplectosphaerella (Plectosphaerellaceae). The newly described species are Alloleptosphaeria clematidis, Anthodidymella ranunculacearum, Anthosulcatispora subglobosa, Aquadictyospora clematidis, Brunneofusispora clematidis, Chaetosphaeronema clematidicola, C. clematidis, Chromolaenicola clematidis, Diaporthe clematidina, Dictyocheirospora clematidis, Distoseptispora clematidis, Floricola clematidis, Fusiformispora clematidis, Hermatomyces clematidis, Leptospora clematidis, Longispora clematidis, Massariosphaeria clematidis, Melomastia clematidis, M. fulvicomae, Neobyssosphaeria clematidis, Neoleptosporella clematidis, Neoroussoella clematidis, N. fulvicomae, Neostictis nigricans, Neovaginatispora clematidis, Parasulcatispora clematidis, Parathyridaria clematidis, P. serratifoliae, P. virginianae, Periconia verrucose, Phomatospora uniseriata, Pleopunctum clematidis, Pseudocapulatispora clematidis, Pseudocoleophoma clematidis, Pseudohelminthosporium clematidis, Pseudolophiostoma chiangraiense, P. clematidis, Pseudomassarina clematidis, Ramusculicola clematidis, Sarocladium clematidis, Sclerenchymomyces clematidis, Sigarispora clematidicola, S. clematidis, S. montanae, Sordaria clematidis, Stemphylium clematidis, Wojnowiciella clematidis, Xenodidymella clematidis, Xenomassariosphaeria clematidis and Xenoplectosphaerella clematidis. The following fungi are recorded on Clematis species for the first time: Angustimassarina rosarum, Dendryphion europaeum, Dermatiopleospora mariae, Diaporthe ravennica, D. rudis, Dichotomopilus ramosissimum, Dictyocheirospora xishuangbannaensis, Didymosphaeria rubi-ulmifolii, Fitzroyomyces cyperacearum, Fusarium celtidicola, Leptospora thailandica, Memnoniella oblongispora, Neodidymelliopsis longicolla, Neoeutypella baoshanensis, Neoroussoella heveae, Nigrograna chromolaenae, N. obliqua, Pestalotiopsis verruculosa, Pseudoberkleasmium chiangmaiense, Pseudoophiobolus rosae, Pseudoroussoella chromolaenae, P. elaeicola, Ramusculicola thailandica, Stemphylium vesicarium and Torula chromolaenae. The new combinations are Anthodidymella clematidis (≡ Didymella clematidis), A. vitalbina (≡ Didymella vitalbina), Anthosulcatispora brunnea (≡ Neobambusicola brunnea), Fuscohypha kunmingensis (≡ Plectosphaerella kunmingensis), Magnibotryascoma rubriostiolata (≡ Teichospora rubriostiolata), Pararoussoella mangrovei (≡ Roussoella mangrovei), Pseudoneoconiothyrium euonymi (≡ Roussoella euonymi), Sclerenchymomyces jonesii (≡ Neoleptosphaeria jonesii), Stemphylium rosae (≡ Pleospora rosae), and S. rosae-caninae (≡ Pleospora rosae-caninae). The microfungi on Clematis is distributed in several classes of Ascomycota. The analyses are based on morphological examination of specimens, coupled with phylogenetic sequence data. To the best of our knowledge, the consolidated species concept approach is recommended in validating species.
    • A microfungus from Costa Rica: <I>Ticosynnema</I> gen. nov.

      Castañeda-Ruiz, Rafael F.; Granados, María M.; Mardones, Melissa; Stadler, Marc; Minter, David W.; Hernández-Restrepo, Margarita; Gené, Josepa; Guarro, Josep (2014-06-10)
    • Minimizing the chaos following the loss of Article 59: Suggestions for a discussion

      Gams, Walter; Humber, Richard A.; Jaklitsch, Walter; Kirschner, Roland; Stadler, Marc (2012-07-03)
    • Minutellins A - D, azaphilones from the stromata of Annulohypoxylon minutellum (Xylariaceae).

      Kuhnert, Eric; Surup, Frank; Halecker, Sandra; Stadler, Marc; Helmholtz Centre for infection research, Inhoffenstr. 7, 38124 Braunschweig, Germany. (2017-02-16)
      During the course of our screening for new metabolites with chemotaxonomic importance from stromata of fungi from the family Xylariaceae, we characterized several interesting metabolites in the fungus Annulohypoxylon minutellum. Extraction of the fruiting bodies and purification by preparative HPLC resulted in the isolation of five metabolites. The main compound was identified as the known metabolite hinnulin A (5), while four minor compounds were found to represent previously undescribed azaphilones, named minutellins A - D (1-4). Their planar structures were elucidated using NMR and HRESIMS data; absolute stereochemistry was assigned by CD data and Mosher's method. Compounds 1, 3 and 5 showed cytotoxic effects against murine and human cells. As the production of 1-5 is restricted to a group of closely related Annulohypoxylon species, they serve well as chemotaxonomic marker.
    • Modular synthesis of polyene side chain analogues of the potent macrolide antibiotic etnangien by a flexible coupling strategy based on hetero-bis-metallated alkenes.

      Altendorfer, Mario; Raja, Aruna; Sasse, Florenz; Irschik, Herbert; Menche, Dirk; University of Heidelberg, Department of Organic Chemistry, INF 270, D-69120 Heidelberg, Germany, EU. (2013-04-07)
      An efficient procedure for the concise synthesis of hetero-bis-metallated alkenes as useful building blocks for the modular access to highly elaborate polyenes and stabilized analogues is reported. By applying these bifunctional olefins in convergent Stille/Suzuki-Miyaura couplings, novel, carefully selected side chain analogues of the potent RNA polymerase inhibitor etnangien were synthesized by a modular late stage coupling strategy and evaluated for antibacterial and antiproliferative activities.
    • Molecular Phylogeny and Morphology of (=Lepteutypa ) (Amphisphaeriaceae).

      Samarakoon, Milan C; Maharachchikumbura, Sajeewa S N; Liu, Jian-Kui Jack; Hyde, Kevin D; Promputtha, Itthayakorn; Stadler, Marc; HZI, Helmholtz Zentrum für Infektionsforschung, GmbH, Inhoffenstr. 7, 38124 Braunschweig, Germany. (MDPI, 2020-09-17)
      Amphisphaeriaceous taxa (fungi) are saprobes on decaying wood in terrestrial, mangrove, and freshwater habitats. The generic boundaries of the family have traditionally been based on morphology, and the delimitation of genera has always been challenging. Amphisphaeria species have clypeate ascomata and 1-septate ascospores and a coelomycetous asexual morph. Lepteutypa is different from Amphisphaeria in having eutypoid stromata and more than 1-septate ascospores. These main characters have been used for segregation of Lepteutypa from Amphisphaeria for a long time. However, the above characters are overlapping among Amphisphaeria and Lepteutypa species. Therefore, here we synonymized Lepteutypa under Amphisphaeria based on holomorphic morphology and multigene phylogeny. Further, our cluster analysis reveals the relationship between seven morphological traits among Amphisphaeria/Lepteutypa species and suggests those morphologies are not specific to either genus. Three new species (i.e., Amphisphaeria camelliae, A. curvaticonidia, and A. micheliae) are introduced based on morphology and LSU-ITS-RPB2-TUB2 phylogenies. Furthermore, the monotypic genus Trochilispora, which had been accepted in Amphisphaeriaceae, is revisited and synonymized under Hymenopleella and placed in Sporocadaceae.
    • Monochlorinated calocerins A-D and 9-oxostrobilurin derivatives from the basidiomycete Favolaschia calocera.

      Chepkirui, Clara; Richter, Christian; Matasyoh, Josphat Clement; Stadler, Marc; Helmholtz Centre for infection research, Ihoffenstr. 7, 38124 Braunschweig, Germany. (2016-12)
      Eight previously undescribed compounds were isolated and characterised from the supernatant and mycelium of a culture of the basidiomycete Favolaschia calocera originating from Kakamega equatorial rainforest in Kenya. These were: 9- oxostrobilurins A, G, K and I and the four monochlorinated calocerins A, B, C and D. The calocerins extend our knowledge of halogenated compounds obtained from natural sources. Four further known compounds were also identified: strobilurin G, favolon, pterulinic acid and 2,3 -dihydro-1-benzoxepin derivative. The four oxostrobilurins exhibited prominent antifungal and cytotoxic activities while the four calocerins only showed cytotoxic activity.
    • Monocillium gamsii sp. nov. and Monocillium bulbillosum: two nematode-associated fungi parasitising the eggs of Heterodera filipjevi

      Ashrafi, Samad; Stadler, Marc; Dababat, Abdelfattah A.; Richert-Pöggeler, Katja R.; Finckh, Maria R.; Maier, Wolfgang; Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr.7, 38124 Braunschweig, Germany. (2017-10-25)
    • A "Motif-Oriented" Total Synthesis of Nannocystin Ax. Preparation and Biological Assessment of Analogues.

      Meng, Zhanchao; Souillart, Laetitia; Monks, Brendan; Huwyler, Nikolas; Herrmann, Jennifer; Müller, Rolf; Fürstner, Alois; HIPS, Helmholtz-Institut füt Pharmazeutische Forschung Saarland, Universitätscampus E8.1 66123 Saarbrücken, Germany. (2018-07-06)
      The highly cytotoxic cyclodepsipeptides of the nannocystin family are known to bind to the eukaryotic translation elongation factor 1α (EF-1α). Analysis of the docking pose, as proposed by a previous in silico study, suggested that the trisubstituted alkene moiety and the neighboring methyl ether form a domain that might be closely correlated with biological activity. This hypothesis sponsored a synthetic campaign which was designed to be "motif-oriented": specifically, a sequence of ring closing alkyne metathesis (RCAM) followed by hydroxy-directed trans-hydrostannation of the resulting cycloalkyne was conceived, which allowed this potentially anchoring substructure to be systematically addressed at a late stage. This inherently flexible approach opened access to nannocystin Ax (1) itself as well as to 10 non-natural analogues. While the biological data confirmed the remarkable potency of this class of compounds and showed that the domain in question is indeed an innate part of the pharmacophore, the specific structure/activity relationships can only partly be reconciled with the original in silico docking study; therefore, we conclude that this model needs to be carefully revisited.
    • Multisystem combined uranium resistance mechanisms and bioremediation potential of Stenotrophomonas bentonitica BII-R7: Transcriptomics and microscopic study

      Pinel-Cabello, M.; Jroundi, F.; López-Fernández, M.; Geffers, R.; Jarek, M.; Jauregui, R.; Link, A.; Vílchez-Vargas, R.; Merroun, M. L.; HZI,Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7,38124 Braunschweig, Germany. (Elsevier, 2021-02-05)
      The potential use of microorganisms in the bioremediation of U pollution has been extensively described. However, a lack of knowledge on molecular resistance mechanisms has become a challenge for the use of these technologies. We reported on the transcriptomic and microscopic response of Stenotrophomonas bentonitica BII-R7 exposed to 100 and 250 μM of U. Results showed that exposure to 100 μM displayed up-regulation of 185 and 148 genes during the lag and exponential phases, respectively, whereas 143 and 194 were down-regulated, out of 3786 genes (>1.5-fold change). Exposure to 250 μM of U showed up-regulation of 68 genes and down-regulation of 290 during the lag phase. Genes involved in cell wall and membrane protein synthesis, efflux systems and phosphatases were up-regulated under all conditions tested. Microscopic observations evidenced the formation of U-phosphate minerals at membrane and extracellular levels. Thus, a biphasic process is likely to occur: the increased cell wall would promote the biosorption of U to the cell surface and its precipitation as U-phosphate minerals enhanced by phosphatases. Transport systems would prevent U accumulation in the cytoplasm. These findings contribute to an understanding of how microbes cope with U toxicity, thus allowing for the development of efficient bioremediation strategies.
    • Myxobacteria in high moor and fen: An astonishing diversity in a neglected extreme habitat.

      Mohr, Kathrin I; Zindler, Tanja; Wink, Joachim; Wilharm, Elke; Stadler, Marc; Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7, 38124 Braunschweig, Germany. (2017-08)
      Increasing antibiotic resistances of numerous pathogens mean that myxobacteria, well known producers of new antibiotics, are becoming more and more interesting. More than 100 secondary metabolites, most of them with bioactivity, were described from the order Myxococcales. Especially new myxobacterial genera and species turned out to be reliable sources for novel antibiotics and can be isolated from uncommon neglected habitats like, for example, acidic soils. Almost nothing is known about the diversity of myxobacteria in moors, except some information from cultivation studies of the 1970s. Therefore, we evaluated the myxobacterial community composition of acidic high moor and fen both with cultivation-independent 16S rRNA clone bank analysis and with cultivation. Phylogenetic analyses of clone sequences revealed a great potential of undescribed myxobacteria in high moor and fen, whereby all sequences represent unknown taxa and were detected exclusively by cultivation-independent analyses. However, many clones were assigned to sequences from other cultivation-independent studies of eubacterial diversity in acidic habitats. Cultivation revealed different strains exclusively from the genus Corallococcus. Our study shows that the neglected habitat moor is a promising source and of high interest with regard to the cultivation of prospective new bioactive secondary metabolite producing myxobacteria.
    • New nematicidal and antimicrobial secondary metabolites from a new species in the new genus, .

      Rupcic, Zeljka; Chepkirui, Clara; Hernández-Restrepo, Margarita; Crous, Pedro W; Luangsa-Ard, Janet Jennifer; Stadler, Marc; Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7, 38124 Braunschweig, Germany. (2018-01-01)
      During the course of a study on the functional biodiversity of the mycobiota inhabiting rainforests in Thailand, a fungal strain was isolated from a plant sample and shown to represent an undescribed species, as inferred from a combination of morphological and molecular phylogenetic methods. Molecular phylogenetic analyses, based on four DNA loci, revealed a phylogenetic tree with the newly generated sequences clustering in a separate branch, together with members of the Sulcatisporaceae (Pleosporales, Ascomycota). The Thai specimen morphologically resembled
    • New nematicidal and antimicrobial secondary metabolites from a new species in the new genus, .

      Rupcic, Zeljka; Chepkirui, Clara; Hernández-Restrepo, Margarita; Crous, Pedro W; Luangsa-Ard, Janet Jennifer; Stadler, Marc; Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7, 38124 Braunschweig, Germany. (2018-01-01)
      During the course of a study on the functional biodiversity of the mycobiota inhabiting rainforests in Thailand, a fungal strain was isolated from a plant sample and shown to represent an undescribed species, as inferred from a combination of morphological and molecular phylogenetic methods. Molecular phylogenetic analyses, based on four DNA loci, revealed a phylogenetic tree with the newly generated sequences clustering in a separate branch, together with members of the Sulcatisporaceae (Pleosporales, Ascomycota). The Thai specimen morphologically resembled
    • New Peptaibiotics and a Cyclodepsipeptide from : Isolation, Identification, Cytotoxic and Nematicidal Activities.

      Moussa, Ashaimaa Y; Lambert, Christopher; Stradal, Theresia E B; Ashrafi, Samad; Maier, Wolfgang; Stadler, Marc; Helaly, Soleiman E; HZI,Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7,38124 Braunschweig, Germany. (MDPI, 2020-03-22)
      Fungal associations with nematodes have attracted scientific attention because of the need to develop new biocontrol agents. In this context, Ijuhya vitellina, an antagonistic fungus previously isolated from the plant parasitic cyst nematode Heterodera filipjevi, was selected to carry out an in-depth metabolomic study for its active metabolites. Herein, three new nonapeptide peptaibols with leucinostatin based sequences were isolated and identified by 1, 2D NMR, and HR-ESI-MS-MS. The absolute configuration was assigned based on Marfay's analysis and Mosher ester formation. The new leucinostatins manifested moderate nematicidal effect against the plant pathogenic nematode Pratylenchus penetrans with LD90 values ranging from 5 to 7 µg/mL. Furthermore, a cyclodepsipeptide, named arthrichitin D, with five amino acid residues attached to a 3-hydroxy-2,4-dimethylhexadeca-4,6-dienoic fatty acid chain was discovered and showed weak nematicidal effect against Caenorhabditis elegans. Chaetoglobosin B and its 19-O-acetyl derivative were also obtained as minor metabolites, and the activity of chaetoglobosin B on the actin cytoskeleton of mammalian cells was assessed.
    • New secondary metabolites produced by the phytopathogenic fungus Wilsonomyces carpophilus

      Narmani, Abolfazl; Teponno, Rémy Bertrand; Arzanlou, Mahdi; Babai-Ahari, Asadollah; Stadler, Marc; Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7, 38124 Braunschweig, Germany.
      wo new metabolites possessing the unusual 1-oxa-7-azaspiro[4.4]non-2- ene-4,6-dione core (2, 3) along with the recently described pseurotin A3 (1) were isolated from the pathogenic fungus Wilsonomyces carpophilus(previously named Stigmina carpophila). The producer organism was obtained from Prunus armeniaca collected in Iran and was identified by morphological and molecular phylogenetic methods. The structures of the isolated compounds were elucidated on the basis of extensive NMR spectroscopic analysis, high-resolution mass spectrometry and ECD analysis. The compounds were screened for their antimicrobial, cytotoxic, nematicidal and biofilm inhibition activities but, no significant effect was observed. To the best of our knowledge, this is the first report on the isolation of secondary metabolites produced by W. carpophilus.