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Didier Stien - One of the best experts on this subject based on the ideXlab platform.
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tyroscherin and tyroscherin analogs from Pseudallescheria boydii snb cn85 isolated from termite termes cf hispaniolae
Phytochemistry Letters, 2017Co-Authors: Jonathan Sorres, Charlotte Nirma, Veronique Eparvier, Morgane Barthelemy, Didier StienAbstract:Abstract Two new tyroscherin derivatives: N -methyl-tyroscherone ( 2 ) and tyroscherin N , O -acetonide ( 3 ), as well as two known secondary metabolites tyroscherin ( 1 ) and pseurotin A ( 4 ), were isolated from a solid culture of the termite-borne fungus Pseudallescheria boydii SNB-CN85. The structures were elucidated by spectroscopic analysis and chemical modification. Compound 3 was synthesized from tyroscherin ( 1 ) in the free amine form by heating in deuterated acetone, followed by deuterium-proton exchange in MeOH. All compounds were tested for their antimicrobial activities on C. albicans and S. aureus , and 2 and 3 exhibited minimal inhibitory concentrations between 128 and 8 μg mL −1 .
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pseudallicins a d four complex ovalicin derivatives from Pseudallescheria boydii snb cn85
Organic Letters, 2017Co-Authors: Jonathan Sorres, Charlotte Nirma, Veronique Eparvier, Didier StienAbstract:The isolation and complete structural elucidation of four complex ovalicin analogues, named pseudallicins A–D, from the fungus Pseudallescheria boydii strain SNB-CN85 are described. On the basis of structural similarities and information from the literature, a joint biosynthetic pathway for the pseudallicins is proposed.
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Pseudallicins A–D: Four Complex Ovalicin Derivatives from Pseudallescheria boydii SNB-CN85
Organic Letters, 2017Co-Authors: Jonathan Sorres, Charlotte Nirma, Veronique Eparvier, Didier StienAbstract:The isolation and complete structural elucidation of four complex ovalicin analogues, named pseudallicins A–D, from the fungus Pseudallescheria boydii strain SNB-CN85 are described. On the basis of structural similarities and information from the literature, a joint biosynthetic pathway for the pseudallicins is proposed.
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antifungal agents from Pseudallescheria boydii snb cn73 isolated from a nasutitermes sp termite
Journal of Natural Products, 2013Co-Authors: Charlotte Nirma, Veronique Eparvier, Didier StienAbstract:Defense mutualisms between social insects and microorganisms have been described in the literature. The present article describes the discovery of a Pseudallescheria boydii strain isolated from Nasutitermes sp. The microbial symbiont produces two antifungal metabolites: tyroscherin and N-methyltyroscherin, a compound not previously described in the literature. Methylation of tyroscherin has confirmed the structure of N-methyltyroscherin. Both compounds are effective antifungal agents with favorable selectivity indices for Candida albicans and Trichophyton rubrum.
G S De Hoog - One of the best experts on this subject based on the ideXlab platform.
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invasive infection caused by Pseudallescheria boydii in an immunocompetent patient
Hippokratia, 2009Co-Authors: E Bibashi, G S De Hoog, E Kostopoulou, M Tsivitanidou, J Sevastidou, P GelerisAbstract:Pseudallescheria boydii is a saprophytic fungus frequently isolated from agricultural soil and polluted water. Disseminated and invasive infections with this organism are seen primarily in the immunocompromised host. We present an unusual case of invasive P. boydii infection in an immunocompetent patient admitted to our hospital with clinical, laboratory and ECG findings of a possible acute myocardiac infarction. Six hours after admission without treatment with thrombolytic agents she presented with a right hemiparesis and loss of consciousness; a CT scan showed a cerebral hemorrage. She was treated with dexamethasone i.v. 32 mg per day. She was not incubated. Two blood cultures taken the 15th and 16th day of hospitalization, respectively, revealed a filamentous fungus which was identified by CBS as P. boydii. The pathologic examination of one nodule showed hyphae of fungi. Despite the administration of amphotericin B the patient died one week later.
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ecology and physiology of the emerging opportunistic fungi Pseudallescheria boydii and scedosporium prolificans
Mycoses, 2009Co-Authors: G S De Hoog, Femke D Marvinsikkema, Greetje A Lahpoor, J C Gottschall, Rudolf A Prins, E GuehoAbstract:Summary. Nutritionally physiological patterns of Pseudallescheria boydii (Microascaceae) and the related species Scedosporium prolificans were established. Differences between the two species were found in assimilation of sucrose, ribitol, xylitol and L-arabinitol. In contrast, no physiological distinction could be made between the three intraspecific variants of P. boydii which have been recognized on the basis of nDNA/DNA homology data and of morphological and clinical differences. Some potential virulence factors were studied in the fungi mentioned above and in some related anamorphs. All species were capable of anaerobic growth, but differed in their temperature relations. Zusammenfassung. Assimilations-Muster von Pseudallescheria boydii (Microascaceae) und der verwandten Art Scedosporium prolificans wurden untersucht. Dabei wurden Art-Unterschiede in der Assimilation von Saccharose, Ribitol, Xylitol und L-Arabinitol festgestellt. Im Gegensatz dazu wurden keine physiologischen Unterschiede zwischen den drei Varianten innerhalb der Art P. boydii nachgewiesen. Damit lassen sich die bisher verwendeten Merkmalsunterschiede, bzw. nDNA/DNA Homologie-Werte sowie morphologische und klinische Characteristika, nicht bestatigen. Einige mogliche Virulenz-Faktoren bei den oben beschriebenen sowie auch bei einigen verwandten Arten, wurden untersucht. Alle Arten erwiesen sich im gleichen Mas zum anaeroben Wachstum befahigt, unterscheiden sich aber in ihrem Temperaturverhalten.
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intraspecific diversity of species of the Pseudallescheria boydii complex
Medical Mycology, 2007Co-Authors: Jingsi Zeng, G S De Hoog, Kazutaka Fukushima, Kayoko Takizawa, Y C Zheng, Kazuko Nishimura, Yvonne GraserAbstract:In order to establish intraspecific diversity of Pseudallescheria boydii and Scedosporium apiospermum, and to develop tools for their identification, variability within P. boydii and related species was investigated at different levels of diversity. Sequences of the D1/D2 region of large subunit (LSU) and of the internal transcribed spacer (ITS) region of ribosomal DNA (rDNA) gene were analyzed for a set of 57 strains, as well as partial sequences of the elongation factor 1-α (EF 1-α). Incongruence among 3 locus lineages was detected by partition homogeneity test (PHT). The maximum parsimony (MP) tree of the combined sequence data set, with the exception of strain CBS 499.90, formed 3 clades with high bootstrap support, corresponding to previously described nuclear DNA (nDNA)/DNA reassociation groups. These groups are known to differ slightly in predilection and temperature relations. Using Structure software, population genetic analysis revealed 3 clusters within the complex on the basis of multi-locus g...
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mycetoma due to Pseudallescheria boydii and co isolation of nocardia abscessus in a patient injured in road accident
Medical Mycology, 2002Co-Authors: R Horre, G S De Hoog, G Schumacher, G Marklein, H Stratmann, E Wardelmann, S Gilges, K P SchaalAbstract:We report the case of a patient who developed a mycetoma after experiencing a road accident. From surgical biopsies Pseudallescheria boydii was isolated. Subsequently, after the infection had been treated with itraconazole, a Grampositive bacterium, identified as the newly described species Nocardia abscessus, was cultured from wound fluids.
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molecular variability of Pseudallescheria boydii a neurotropic opportunist
Journal of Clinical Microbiology, 2000Co-Authors: J Rainer, G S De Hoog, M Wedde, Y Graser, S GilgesAbstract:The sequences of the internal transcribed spacer (ITS) ribosomal DNA (rDNA) domain data obtained by restriction fragment length polymorphism analysis with 18S rDNA and fingerprinting (M13) for clinical and environmental strains of Pseudallescheria boydii (anamorph, Scedosporium apiospermum) were compared to those for related species of Pseudallescheria, Petriella, and Scedosporium. The infraspecific variability of P. boydii was considerable. There were five different lengths in the 18S rDNAs within P. boydii due to the occurrence of introns. In several cases, strains isolated from a single pond or ditch proved to be genetically very different. Nevertheless, some lineages had a regional distribution. The variability found is unlikely to be explained by meiotic recombination alone. Pseudallescheria fusoidea, Pseudallescheria ellipsoidea, and Pseudallescheria angusta were found to be synonyms for P. boydii. Scedosporium prolificans was found amid Petriella species in the ITS tree and showed no infraspecific variability. The type strain of Rhinocladium lesnei proved to be identical to Graphium putredinis. Acladium castellanii, which is morphologically reminiscent of S. apiospermum, was also found to be a separate species, but with an unknown affiliation.
Josep Guarro - One of the best experts on this subject based on the ideXlab platform.
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molecular and phenotypic data supporting distinct species statuses for scedosporium apiospermum and Pseudallescheria boydii and the proposed new species scedosporium dehoogii
Journal of Clinical Microbiology, 2008Co-Authors: Felix Gilgado, Josep Cano, Josepa Gene, Deanna A Sutton, Josep GuarroAbstract:Based on the morphological, physiologic, and molecular (β-tubulin gene) study of 141 isolates of the Pseudallescheria boydii species complex (including several synonyms) and relatives, the new species Scedosporium dehoogii is proposed. Scedosporium apiospermum and P. boydii are considered two different species and the new name Scedosporium boydii is proposed for the anamorph of the latter species. A summary of the key morphological and physiological features for distinguishing the species of Pseudallescheria/Scedosporium is provided.
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antifungal susceptibilities of the species of the Pseudallescheria boydii complex
Antimicrobial Agents and Chemotherapy, 2006Co-Authors: Felix Gilgado, Carolina Serena, Josep Cano, Josepa Gene, Josep GuarroAbstract:Eighty-four isolates belonging to eight species that constitute the Pseudallescheria boydii complex were tested against 11 antifungal agents by using the microdilution method. There were significant differences among the species, with Scedosporium aurantiacum being the most resistant. In general, voriconazole was the most active drug, followed by posaconazole.
Charlotte Nirma - One of the best experts on this subject based on the ideXlab platform.
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tyroscherin and tyroscherin analogs from Pseudallescheria boydii snb cn85 isolated from termite termes cf hispaniolae
Phytochemistry Letters, 2017Co-Authors: Jonathan Sorres, Charlotte Nirma, Veronique Eparvier, Morgane Barthelemy, Didier StienAbstract:Abstract Two new tyroscherin derivatives: N -methyl-tyroscherone ( 2 ) and tyroscherin N , O -acetonide ( 3 ), as well as two known secondary metabolites tyroscherin ( 1 ) and pseurotin A ( 4 ), were isolated from a solid culture of the termite-borne fungus Pseudallescheria boydii SNB-CN85. The structures were elucidated by spectroscopic analysis and chemical modification. Compound 3 was synthesized from tyroscherin ( 1 ) in the free amine form by heating in deuterated acetone, followed by deuterium-proton exchange in MeOH. All compounds were tested for their antimicrobial activities on C. albicans and S. aureus , and 2 and 3 exhibited minimal inhibitory concentrations between 128 and 8 μg mL −1 .
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pseudallicins a d four complex ovalicin derivatives from Pseudallescheria boydii snb cn85
Organic Letters, 2017Co-Authors: Jonathan Sorres, Charlotte Nirma, Veronique Eparvier, Didier StienAbstract:The isolation and complete structural elucidation of four complex ovalicin analogues, named pseudallicins A–D, from the fungus Pseudallescheria boydii strain SNB-CN85 are described. On the basis of structural similarities and information from the literature, a joint biosynthetic pathway for the pseudallicins is proposed.
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Pseudallicins A–D: Four Complex Ovalicin Derivatives from Pseudallescheria boydii SNB-CN85
Organic Letters, 2017Co-Authors: Jonathan Sorres, Charlotte Nirma, Veronique Eparvier, Didier StienAbstract:The isolation and complete structural elucidation of four complex ovalicin analogues, named pseudallicins A–D, from the fungus Pseudallescheria boydii strain SNB-CN85 are described. On the basis of structural similarities and information from the literature, a joint biosynthetic pathway for the pseudallicins is proposed.
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antifungal agents from Pseudallescheria boydii snb cn73 isolated from a nasutitermes sp termite
Journal of Natural Products, 2013Co-Authors: Charlotte Nirma, Veronique Eparvier, Didier StienAbstract:Defense mutualisms between social insects and microorganisms have been described in the literature. The present article describes the discovery of a Pseudallescheria boydii strain isolated from Nasutitermes sp. The microbial symbiont produces two antifungal metabolites: tyroscherin and N-methyltyroscherin, a compound not previously described in the literature. Methylation of tyroscherin has confirmed the structure of N-methyltyroscherin. Both compounds are effective antifungal agents with favorable selectivity indices for Candida albicans and Trichophyton rubrum.
Veronique Eparvier - One of the best experts on this subject based on the ideXlab platform.
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tyroscherin and tyroscherin analogs from Pseudallescheria boydii snb cn85 isolated from termite termes cf hispaniolae
Phytochemistry Letters, 2017Co-Authors: Jonathan Sorres, Charlotte Nirma, Veronique Eparvier, Morgane Barthelemy, Didier StienAbstract:Abstract Two new tyroscherin derivatives: N -methyl-tyroscherone ( 2 ) and tyroscherin N , O -acetonide ( 3 ), as well as two known secondary metabolites tyroscherin ( 1 ) and pseurotin A ( 4 ), were isolated from a solid culture of the termite-borne fungus Pseudallescheria boydii SNB-CN85. The structures were elucidated by spectroscopic analysis and chemical modification. Compound 3 was synthesized from tyroscherin ( 1 ) in the free amine form by heating in deuterated acetone, followed by deuterium-proton exchange in MeOH. All compounds were tested for their antimicrobial activities on C. albicans and S. aureus , and 2 and 3 exhibited minimal inhibitory concentrations between 128 and 8 μg mL −1 .
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pseudallicins a d four complex ovalicin derivatives from Pseudallescheria boydii snb cn85
Organic Letters, 2017Co-Authors: Jonathan Sorres, Charlotte Nirma, Veronique Eparvier, Didier StienAbstract:The isolation and complete structural elucidation of four complex ovalicin analogues, named pseudallicins A–D, from the fungus Pseudallescheria boydii strain SNB-CN85 are described. On the basis of structural similarities and information from the literature, a joint biosynthetic pathway for the pseudallicins is proposed.
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Pseudallicins A–D: Four Complex Ovalicin Derivatives from Pseudallescheria boydii SNB-CN85
Organic Letters, 2017Co-Authors: Jonathan Sorres, Charlotte Nirma, Veronique Eparvier, Didier StienAbstract:The isolation and complete structural elucidation of four complex ovalicin analogues, named pseudallicins A–D, from the fungus Pseudallescheria boydii strain SNB-CN85 are described. On the basis of structural similarities and information from the literature, a joint biosynthetic pathway for the pseudallicins is proposed.
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antifungal agents from Pseudallescheria boydii snb cn73 isolated from a nasutitermes sp termite
Journal of Natural Products, 2013Co-Authors: Charlotte Nirma, Veronique Eparvier, Didier StienAbstract:Defense mutualisms between social insects and microorganisms have been described in the literature. The present article describes the discovery of a Pseudallescheria boydii strain isolated from Nasutitermes sp. The microbial symbiont produces two antifungal metabolites: tyroscherin and N-methyltyroscherin, a compound not previously described in the literature. Methylation of tyroscherin has confirmed the structure of N-methyltyroscherin. Both compounds are effective antifungal agents with favorable selectivity indices for Candida albicans and Trichophyton rubrum.
