25 results on '"Clara Chepkirui"'
Search Results
2. Skeletocutins M–Q: biologically active compounds from the fruiting bodies of the basidiomycete Skeletocutis sp. collected in Africa
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Tian Cheng, Clara Chepkirui, Cony Decock, Josphat C. Matasyoh, and Marc Stadler
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basidiomycete ,polyporaceae ,secondary metabolites ,structure elucidation ,Science ,Organic chemistry ,QD241-441 - Abstract
During the course of screening for new metabolites from basidiomycetes, we isolated and characterized five previously undescribed secondary metabolites, skeletocutins M–Q (1–5), along with the known metabolite tyromycin A (6) from the fruiting bodies of the polypore Skeletocutis sp. The new compounds did not exhibit any antimicrobial, cytotoxic, or nematicidal activities. However, compound 3 moderately inhibited the biofilm formation of Staphylococcus aureus (S. aureus), while compounds 3 and 4 performed moderately in the ʟ-leucine-7-amido-4-methylcoumarin (ʟ-Leu-AMC) inhibition assay. These compounds represent the first secondary metabolites reported to occur in the fruiting bodies by Skeletocutis. Interestingly, tyromycin A (6) was found to be the only common metabolite in fruiting bodies and mycelial cultures of the fungus, and none of the recently reported skeletocutins from the culture of the same strain were detected in the basidiomes.
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- 2019
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3. Neurotrophic and Immunomodulatory Lanostane Triterpenoids from Wood-Inhabiting Basidiomycota
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Khadija Hassan, Blondelle Matio Kemkuignou, Marco Kirchenwitz, Kathrin Wittstein, Monique Rascher-Albaghdadi, Clara Chepkirui, Josphat C. Matasyoh, Cony Decock, Reinhard W. Köster, Theresia E. B. Stradal, and Marc Stadler
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neurodegenerative diseases ,ngf ,bdnf ,triterpenoids ,pheochromocytoma cells ,astrocytoma cells ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Neurotrophins such as nerve growth factor (ngf) and brain-derived neurotrophic factor (bdnf) play important roles in the central nervous system. They are potential therapeutic drugs for the treatment of neurodegenerative diseases, including Alzheimer’s disease and Parkinson’s disease. In this study, we investigated the neurotrophic properties of triterpenes isolated from fruiting bodies of Laetiporus sulphureus and a mycelial culture of Antrodia sp. MUCL 56049. The structures of the isolated compounds were elucidated based on nuclear magnetic resonance (NMR) spectroscopy in combination with high-resolution electrospray mass spectrometry (HR-ESIMS). The secondary metabolites were tested for neurotrophin (ngf and bdnf) expression levels on human astrocytoma 1321N1 cells. Neurite outgrowth activity using rat pheochromocytoma (PC-12) cells was also determined. Twelve triterpenoids were isolated, of which several potently stimulated the expression of neurotrophic factors, namely, ngf (sulphurenic acid, 15α-dehydroxytrametenolic acid, fomefficinic acid D, and 16α-hydroxyeburicoic acid) and bdnf (sulphurenic acid and 15α-dehydroxytrametenolic acid), respectively. The triterpenes also potentiated ngf-induced neurite outgrowth in PC-12 cells. This is, to the best of our knowledge, the first report on the compound class of lanostanes in direct relation to bdnf and ngf enhancement. These compounds are widespread in medicinal mushrooms; hence, they appear promising as a starting point for the development of drugs and mycopharmaceuticals to combat neurodegenerative diseases. Interestingly, they do not show any pronounced cytotoxicity and may, therefore, be better suited for therapy than many other neurotrophic compounds that were previously reported.
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- 2022
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4. Author Correction: Engineering the stambomycin modular polyketide synthase yields 37-membered mini-stambomycins
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Li Su, Laurence Hôtel, Cédric Paris, Clara Chepkirui, Alexander O. Brachmann, Jörn Piel, Christophe Jacob, Bertrand Aigle, and Kira J. Weissman
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Science - Published
- 2022
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5. Meroterpenoids Possibly Produced by a Bacterial Endosymbiont of the Tropical Basidiomycete Echinochaete brachypora
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Khadija Hassan, Clara Chepkirui, Natalia Andrea Llanos-López, Josphat C. Matasyoh, Cony Decock, Yasmina Marin-Felix, and Marc Stadler
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endosymbiosis ,neomarinone ,fumaquinone ,endofungal bacteria ,Ralstonia ,Microbiology ,QR1-502 - Abstract
A mycelial culture of the African basidiomycete Echinochaete cf. brachypora was studied for biologically active secondary metabolites, and four compounds were isolated from its crude extract derived from shake flask fermentations, using preparative high-performance liquid chromatography (HPLC). The pure metabolites were identified using extensive nuclear magnetic resonance (NMR) spectroscopy and high-resolution mass spectrometry (HR-MS). Aside from the new metabolites 1-methoxyneomarinone (1) and (E)-3-methyl-5-(-12,13,14-trimethylcyclohex-10-en-6-yl)pent-2-enoic acid (4), the known metabolites neomarinone (2) and fumaquinone (4) were obtained. Such compounds had previously only been reported from Actinobacteria but were never isolated from the cultures of a fungus. This observation prompted us to evaluate whether the above metabolites may actually have been produced by an endosymbiontic bacterium that is associated with the basidiomycete. We have indeed been able to characterize bacterial 16S rDNA in the fungal mycelia, and the production of the metabolites stopped when the fungus was sub-cultured on a medium containing antibacterial antibiotics. Therefore, we have found strong evidence that compounds 1–4 are not of fungal origin. However, the endofungal bacterium was shown to belong to the genus Ralstonia, which has never been reported to produce similar metabolites to 1–4. Moreover, we failed to obtain the bacterial strain in pure culture to provide final proof for its identity. In any case, the current report is the first to document that polyporoid Basidiomycota are associated with endosymbionts and constitutes the first report on secondary metabolites from the genus Echinochaete.
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- 2022
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6. New nematicidal and antimicrobial secondary metabolites from a new species in the new genus, Pseudobambusicola thailandica
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Zeljka Rupcic, Clara Chepkirui, Margarita Hernández-Restrepo, Pedro W. Crous, Janet Jennifer Luangsa-ard, and Marc Stadler
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Botany ,QK1-989 - Abstract
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 Neobambusicola strelitziae in having pycnidial conidiomata with phialidic conidiogenous cells that produce both fusoid-ellipsoid macroconidia and subcylindrical microconidia. However, the new fungus, for which the name Pseudobambusicola thailandica is proposed, differs from N. strelitziae in having conidiomata with well-defined necks, the presence of globose to subglobose thick-walled cells adjacent to conidiomata and the production of chlamydospores in culture. When cultures of P. thailandica, growing on water agar, were confronted with Caenorhabditis elegans nematodes, worms approaching the fungal mycelia were killed. This observation gave rise to a study of its secondary metabolites and six novel and two known compounds were isolated from submerged cultures of P. thailandica. The structures of metabolites 1–6, for which the trivial names thailanones A–F are proposed, were elucidated using a combination of spectral methods, including extensive 1 and 2D NMR analysis and high resolution mass spectrometry. Compounds 4 and 8 showed strong nematicidal and weak antifungal activity, whereas all other tested compounds showed moderate to weak nematicidal activity but no significant effects in the serial dilution assay against various fungi and bacteria. Compounds 1 and 8 also inhibited growth of the pathogenic basidiomycete Phellinus tremulae in a plate diffusion assay.
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- 2018
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7. Cytochalasans Act as Inhibitors of Biofilm Formation of Staphylococcus aureus
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Kamila Tomoko Yuyama, Lucile Wendt, Frank Surup, Robin Kretz, Clara Chepkirui, Kathrin Wittstein, Chollaratt Boonlarppradab, Sarunyou Wongkanoun, Jennifer Luangsa-ard, Marc Stadler, and Wolf-Rainer Abraham
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ascomycota ,bacterial pathogens ,biofilm dispersion ,chromatography ,natural products ,secondary metabolites ,structure elucidation ,Xylariales ,Microbiology ,QR1-502 - Abstract
During the course of our ongoing work to discover new inhibitors of biofilm formation of Staphylococcus aureus from fungal sources, we observed biofilm inhibition by cytochalasans isolated from cultures of the ascomycete Hypoxylon fragiforme for the first time. Two new compounds were purified by a bioassay-guided fractionation procedure; their structures were elucidated subsequently by nuclear magnetic resonance (NMR) spectroscopy and high-resolution mass spectrometry (HR-MS). This unexpected finding prompted us to test further cytochalasans from other fungi and from commercial sources for comparison. Out of 21 cytochalasans, 13 showed significant inhibition of Staphylococcus aureus biofilm formation at subtoxic levels. These findings indicate the potential of cytochalasans as biofilm inhibitors for the first time, also because the minimum inhibitory concentrations (MIC) are independent of the anti-biofilm activities. However, cytochalasans are known to be inhibitors of actin, making some of them very toxic for eukaryotic cells. Since the chemical structures of the tested compounds were rather diverse, the inclusion of additional derivatives, as well as the evaluation of their selectivity against mammalian cells vs. the bacterium, will be necessary as next step in order to develop structure-activity relationships and identify the optimal candidates for development of an anti-biofilm agent.
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- 2018
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8. Aethiopinolones A–E, New Pregnenolone Type Steroids from the East African Basidiomycete Fomitiporia aethiopica
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Clara Chepkirui, Winnie C. Sum, Tian Cheng, Josphat C. Matasyoh, Cony Decock, and Marc Stadler
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cytotoxicity ,fungi ,Hymenochaetaceae ,triterpenes ,Organic chemistry ,QD241-441 - Abstract
A mycelial culture of the Kenyan basidiomycete Fomitiporia aethiopica was fermented on rice and the cultures were extracted with methanol. Subsequent HPLC profiling and preparative chromatography of its crude extract led to the isolation of five previously undescribed pregnenolone type triterpenes 1–5, for which we propose the trivial name aethiopinolones A–E. The chemical structures of the aethiopinolones were determined by extensive 1D- and 2D-NMR, and HRMS data analysis. The compounds exhibited moderate cytotoxic effects against various human cancer cell lines, but they were found devoid of significant nematicidal and antimicrobial activities.
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- 2018
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9. Bioactive Compounds Produced by Hypoxylon fragiforme against Staphylococcus aureus Biofilms
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Kamila Tomoko Yuyama, Clara Chepkirui, Lucile Wendt, Diana Fortkamp, Marc Stadler, and Wolf-Rainer Abraham
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biofilm dispersion ,Staphylococcus aureus ,Hypoxylon fragiforme ,secondary metabolites ,Biology (General) ,QH301-705.5 - Abstract
Treating infections organized in biofilms is a challenge due to the resistance of the pathogens against antibiotics and host immune cells. Many fungi grow in a wet environment, favorable for the growth of bacterial biofilms, and we speculated that fungi possess some strategies to control these bacterial biofilms. A fungus identified as Hypoxylon fragiforme, was collected in the Harz Mountains, Germany, and its mycelial culture was fermented in different culture media for 67 days to test its biological potential against bacterial biofilms. Sclerin, sclerin diacid and its 3-methyl monoester (methyl 1-(5-hydroxy-6-carboxylic-2,3,4-trimethylphenyl) propionate) are here described for the first time from this fungus. Sclerin and its diacid interfered with the biofilm formation of the pathogen Staphylococcus aureus, inhibiting 86% and 80% of the biofilm at 256 μg mL−1, respectively, but not killing the bacterium. Interestingly, the monomethylester of sclerin diacid was inactive. Although these compounds did not possess any activity against a pre-formed biofilm, they prevented its formation at subtoxic concentrations. Furthermore, sclerin and its diacid displayed a high specificity against Staphylococcus aureus, indicating a good strategy against pathogenic biofilms when combined with antibiotics.
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- 2017
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10. Neurotrophic and Immunomodulatory Lanostane Triterpenoids from Wood-Inhabiting Basidiomycota
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Khadija Hassan, Blondelle Matio Kemkuignou, Marco Kirchenwitz, Kathrin Wittstein, Monique Rascher- Albaghdadi, Clara Chepkirui, Josphat C. Matasyoh, Cony Decock, Reinhard W. Köster, and Marc Stadler
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neurodegenerative diseases ,ngf ,bdnf ,triterpenoids ,pheochromocytoma cells ,astrocytoma cells - Abstract
Neurotrophins such as nerve growth factor (ngf) and brain-derived neurotrophic factor (bdnf) play important roles in the central nervous system. They are potential therapeutic drugs for the treatment of neurodegenerative diseases, including Alzheimer’s disease and Parkinson’s disease. In this study, we investigated the neurotrophic properties of triterpenes isolated from fruiting bodies of Laetiporus sulphureus and a mycelial culture of Antrodia sp. MUCL 56049. The structures of the isolated compounds were elucidated based on nuclear magnetic resonance (NMR) spectroscopy in combination with high-resolution electrospray mass spectrometry (HR-ESIMS). The secondary metabolites were tested for neurotrophin (ngf and bdnf) expression levels on human astrocytoma 1321N1 cells. Neurite outgrowth activity using rat pheochromocytoma (PC-12) cells was also determined. Twelve triterpenoids were isolated, of which several potently stimulated the expression of neurotrophic factors, namely, ngf (sulphurenic acid, 15α-dehydroxytrametenolic acid, fomefficinic acid D, and 16α-hydroxyeburicoic acid) and bdnf (sulphurenic acid and 15α- dehydroxytrametenolic acid), respectively. The triterpenes also potentiated ngf-induced neurite outgrowth in PC-12 cells. This is, to the best of our knowledge, the first report on the compound class of lanostanes in direct relation to bdnf and ngf enhancement. These compounds are widespread in medicinal mushrooms; hence, they appear promising as a starting point for the development of drugs and mycopharmaceuticals to combat neurodegenerative diseases. Interestingly, they do not show any pronounced cytotoxicity and may, therefore, be better suited for therapy than many other neurotrophic compounds that were previously reported.
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- 2023
11. Widespread microbial utilization of ribosomal β-amino acid-containing peptides and proteins
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Thomas A. Scott, Marjan Verest, Jakob Farnung, Clarissa C. Forneris, Serina L. Robinson, Xinjian Ji, Florian Hubrich, Clara Chepkirui, Daniel U. Richter, Stefanie Huber, Philipp Rust, Alena B. Streiff, Qi Zhang, Jeffrey W. Bode, and Jörn Piel
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General Chemical Engineering ,Biochemistry (medical) ,Materials Chemistry ,natural products ,peptides ,proteins ,β-amino acids ,bacteria ,protease inhibitors ,genome mining ,ribosomally synthesized and posttranslationally modified peptides ,ketoamides ,Environmental Chemistry ,General Chemistry ,Biochemistry - Abstract
β-Amino residues are regarded as extremely rare features among ribosomal products. They can be installed by a remarkable non-canonical enzymatic splicing process occurring in some Nif11-type ribosomally synthesized and posttranslationally modified peptide (RiPP) pathways from select cyanobacteria. The functions of the final pathway products remained unknown. Here, a global bioinformatic analysis suggested an unexpectedly broad distribution of ribosomal β-amino acid products in diverse bacterial lineages as well as archaea. Characterization of 27 bacterial splicease-substrate pairs confirmed the modification in all cases. The “spliceotide” products include many previously unrecognized RiPP types as well as proteins, contain 35 to >600 residues, and feature single to multiple α-keto-β-amino acid moieties, with 15 different naturally occurring β units characterized and 20 predicted. Of three tested spliceotides, all exhibited exceptionally potent protease inhibitory activity, providing a potential rationale for the widespread splicease chemistry in prokaryotes and highlighting substantial potential for drug discovery and gene-based biomolecule diversification. ISSN:2451-9294 ISSN:2451-9308
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- 2022
12. Heimiomycins A–C and Calamenens from the African Basidiomycete Heimiomyces sp
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Cony Decock, Tian Cheng, Josphat C. Matasyoh, Clara Chepkirui, Marc Stadler, and UCL - SST/ELI/ELIM - Applied Microbiology
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Pharmacology ,biology ,Phenanthridine ,Stereochemistry ,Organic Chemistry ,Heimiomyces ,Pharmaceutical Science ,biology.organism_classification ,Antimicrobial ,Terpenoid ,Analytical Chemistry ,chemistry.chemical_compound ,Mucor hiemalis ,Complementary and alternative medicine ,chemistry ,Drug Discovery ,Molecular Medicine ,Moiety ,Cytotoxicity ,Bacteria - Abstract
Three previously undescribed compounds named heimiomycin A−C (1−3), featuring a unique scaffold with calamenene connected to a hydroxystyryl-pyranone moiety, along with the new calamenene derivatives 4 and 5 and phenanthridine derivative (6) were obtained from a culture of a Heimiomyces sp. This is the first report of the occurrence of calamenene-type terpenoids in fungi. Compound 3 exhibited antimicrobial activity against Gram-positive bacteria and Mucor hiemalis. Compounds 1 and 3 displayed moderate cytotoxicity against KB 3.1 and L929 cell lines, respectively.
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- 2020
13. Ribosomally derived lipopeptides containing distinct fatty acyl moieties
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Florian Hubrich, Nina M. Bösch, Clara Chepkirui, Brandon I. Morinaka, Michael Rust, Muriel Gugger, Serina L. Robinson, Anna L. Vagstad, Jörn Piel, Eidgenössische Technische Hochschule - Swiss Federal Institute of Technology [Zürich] (ETH Zürich), National University of Singapore (NUS), Collection des Cyanobactéries, Institut Pasteur [Paris] (IP)-Université Paris Cité (UPCité), Swiss Federal Insitute of Aquatic Science and Technology [Dübendorf] (EAWAG), and We are grateful for financial support (F.H. for financial support by the Vontobel Foundation, S.L.R. for financial support by the ETH Zürich Postdoctoral Fellowship [20-1 FEL-07], and J.P. for financial support by the Swiss National Science Foundation (SNSF) [National Research Program 72 'Antimicrobial resistance,' 407240_167051]).
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Antifungal Agents ,Multidisciplinary ,N-acylation ,natural products ,[SDV]Life Sciences [q-bio] ,Biological Sciences ,Cyanobacteria ,Biochemistry ,Peptides, Cyclic ,Anti-Bacterial Agents ,Biosynthetic Pathways ,RiPPs ,peptides ,biosynthesis ,Lipopeptides ,lipids (amino acids, peptides, and proteins) ,Peptide Synthases ,Ribosomes - Abstract
Lipopeptides represent a large group of microbial natural products that include important antibacterial and antifungal drugs and some of the most-powerful known biosurfactants. The vast majority of lipopeptides comprise cyclic peptide backbones N-terminally equipped with various fatty acyl moieties. The known compounds of this type are biosynthesized by nonribosomal peptide synthetases, giant enzyme complexes that assemble their products in a non-gene-encoded manner. Here, we report the genome-guided discovery of ribosomally derived, fatty-acylated lipopeptides, termed selidamides. Heterologous reconstitution of three pathways, two from cyanobacteria and one from an arctic, ocean-derived alphaproteobacterium, allowed structural characterization of the probable natural products and suggest that selidamides are widespread over various bacterial phyla. The identified representatives feature cyclic peptide moieties and fatty acyl units attached to (hydroxy)ornithine or lysine side chains by maturases of the GCN5-related N-acetyltransferase superfamily. In contrast to nonribosomal lipopeptides that are usually produced as congener mixtures, the three selidamides are selectively fatty acylated with C10, C12, or C16 fatty acids, respectively. These results highlight the ability of ribosomal pathways to emulate products with diverse, nonribosomal-like features and add to the biocatalytic toolbox for peptide drug improvement and targeted discovery., Proceedings of the National Academy of Sciences of the United States of America, 119 (3), ISSN:0027-8424, ISSN:1091-6490
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- 2022
14. Enzyme-mediated backbone N-methylation in ribosomally encoded peptides
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Emmanuel Matabaro, Michael F. Freeman, Luca Witte, Clara Chepkirui, Hannelore Kaspar, James H. Naismith, Markus Künzler, Haigang Song, and Petersson, E. James
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chemistry.chemical_classification ,Ascomycota ,biology ,Omphalotus olearius ,Heterologous ,Peptide ,biology.organism_classification ,medicine.disease_cause ,Pichia pastoris ,Enzyme ,Lentinula ,chemistry ,Biochemistry ,medicine ,Escherichia coli - Abstract
Backbone N-methylation as a posttranslational modification was recently discovered in a class of ribosomally encoded peptides referred to as borosins. The founding members of the borosins are the omphalotins (A-I), backbone N-methylated, macrocyclic dodecapeptides produced by the mushroom Omphalotus olearius. Omphalotins display a strong and selective toxicity toward the plant parasitic nematode Meloidogyne incognita. The primary product omphalotin A is synthesized via a concerted action of the omphalotin precursor protein (OphMA) and the dual function prolyloligopeptidase/macrocyclase (OphP). OphMA consists of α-N-methyltransferase domain that autocatalytically methylates the core peptide fused to its C-terminus via a clasp domain. Genome mining uncovered over 50 OphMA homologs from the fungal phyla Ascomycota and Basidiomycota. However, the derived peptide natural products have not been described yet, except for lentinulins, dendrothelins and gymnopeptides produced by the basidiomycetes Lentinula edodes, Dendrothele bispora and Gymnopus fusipes, respectively. In this chapter, we describe methods used to isolate and characterize these backbone N-methylated peptides and their precursor proteins both in their original hosts and in the heterologous hosts Escherichia coli and Pichia pastoris. These methods may pave the path for both the discovery of novel borosins with interesting bioactivities. In addition, understanding of borosin biosynthetic pathways may allow setting up a biotechnological platform for the production of pharmaceutical leads for orally available peptide drugs., Methods in Enzymology, 656, ISSN:0076-6879, Synthetic and Enzymatic Modifications of the Peptide Backbone
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- 2021
15. Microporenic Acids A–G, Biofilm Inhibitors, and Antimicrobial Agents from the Basidiomycete Microporus Species
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Marc Stadler, Kamila Tomoko Yuyama, Cony Decock, Clara Chepkirui, Lucy A. Wanga, Wolf-Rainer Abraham, and Josphat C. Matasyoh
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0301 basic medicine ,Staphylococcus aureus ,Gram-positive bacteria ,030106 microbiology ,Pharmaceutical Science ,Microbial Sensitivity Tests ,Gram-Positive Bacteria ,medicine.disease_cause ,01 natural sciences ,Cell Line ,Analytical Chemistry ,Microbiology ,Mice ,03 medical and health sciences ,Antibiotic resistance ,Anti-Infective Agents ,Cell Line, Tumor ,Candida albicans ,Drug Discovery ,medicine ,Animals ,Humans ,Polyporales ,Pharmacology ,biology ,010405 organic chemistry ,Basidiomycota ,Organic Chemistry ,Biofilm ,Antimicrobial ,biology.organism_classification ,Kenya ,0104 chemical sciences ,Complementary and alternative medicine ,Biofilms ,Molecular Medicine ,Microporus ,HeLa Cells - Abstract
The need for effective compounds to combat antimicrobial resistance and biofilms which play important roles in human infections continues to pose a major health challenge. Seven previously undescribed acyclic diterpenes linked to isocitric acid by an ether linkage, microporenic acids A-G (1-7), were isolated from the cultures of a hitherto undescribed species of the genus Microporus (Polyporales, Basidiomycota) originating from Kenya's Kakamega forest. Microporenic acids D and E (4 and 5) showed antimicrobial activity against a panel of Gram positive bacteria and a yeast, Candida tenuis. Moreover, microporenic acids A and B (1 and 2) demonstrated dose-dependent inhibition of biofilm formation by Staphylococcus aureus. Compound 1 further showed significant activity against Candida albicans and Staphylococcus aureus preformed biofilms.
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- 2018
16. Two cytotoxic triterpenes from cultures of a Kenyan Laetiporus sp. (Basidiomycota)
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Cony Decock, Josphat C. Matasyoh, Clara Chepkirui, Marc Stadler, and HZI,Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7,38124 Braunschweig, Germany.
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0301 basic medicine ,Stereochemistry ,Cytotoxicity ,Terpenoids ,Fungi ,Basidiomycota ,Plant Science ,Biology ,biology.organism_classification ,Antimicrobial ,Trametenolic acid ,Biochemistry ,Lanostane ,Terpenoid ,Microbiology ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,chemistry ,Medicinal fungi ,Polyporales ,Agronomy and Crop Science ,Laetiporus ,Biotechnology - Abstract
HPLC profiling of the mycelial culture of a poroid basidomycete collected in Mount Elgon, Kenya, which probably represents a new species of the genus Laetiporus , led to isolation of two previously undescribed lanostane type triterpenes.We propose the trivial names laetiporins A ( 1 ) and B ( 2 ). In addition, five known ones: dehydrosulphurenic acid ( 3 ), sulphurenic acid ( 4 ), eburicoic acid ( 5 ), 15α-hydroxytrametenolic acid ( 6 ) and trametenolic acid ( 7 ) were also isolated. The laetiporins ( 1–2 ) exhibited significant cytotoxic effects against various human cancer cells. The known compounds ( 3–5 ) and ( 7 ) also showed moderate cytotoxic activity, but none of the compounds showed any significant antimicrobial activity.
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- 2017
17. Skeletocutins A-L: Antibacterial Agents from the Kenyan Wood-Inhabiting Basidiomycete
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Clara, Chepkirui, Tian, Cheng, Winnie Chemutai, Sum, Josphat Clement, Matasyoh, Cony, Decock, Dimas F, Praditya, Kathrin, Wittstein, Eike, Steinmann, and Marc, Stadler
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Molecular Structure ,Hepacivirus ,Microbial Sensitivity Tests ,Polyporales ,Antiviral Agents ,Kenya ,Wood ,Anti-Bacterial Agents - Abstract
Fermentation of the fungal strain
- Published
- 2019
18. Sesquiterpenes from an Eastern African Medicinal Mushroom Belonging to the Genus Sanghuangporus
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Josphat C. Matasyoh, Cony Decock, Tian Cheng, Clara Chepkirui, Marc Stadler, UCL - SST/ELI/ELIM - Applied Microbiology, and HZI,Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7,38124 Braunschweig, Germany.
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Antifungal ,Magnetic Resonance Spectroscopy ,medicine.drug_class ,Pharmaceutical Science ,Microbial Sensitivity Tests ,Biology ,01 natural sciences ,Analytical Chemistry ,Medicinal mushroom ,Anti-Infective Agents ,Genus ,Tandem Mass Spectrometry ,Cell Line, Tumor ,Drug Discovery ,medicine ,Humans ,Sanghuangporus ,Pharmacology ,Antibiotics, Antineoplastic ,Traditional medicine ,Bacteria ,Molecular Structure ,010405 organic chemistry ,Basidiomycota ,Organic Chemistry ,Fungi ,Africa, Eastern ,Kenya ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,Inonotus linteus ,Complementary and alternative medicine ,Fermentation ,Molecular Medicine ,Drug Screening Assays, Antitumor ,Agaricales ,Sesquiterpenes - Abstract
During the course of searching for new anti-infective and other biologically active secondary metabolites from Kenyan basidiomycetes, 13 previously undescribed metabolites, (6 R,7 S,10 R)-7,10-epoxy-7,11-dimethyldodec-1-ene-6,11-diol (1) and 12 sesquiterpenes named elgonenes A-L (2-13), and the known compound P-coumaric acid (14) were isolated from a basidiomycete collected in Mount Elgon Natural Reserve. The producing organism represents a new species of the genus Sanghuangporus, which is one of the segregates of the important traditional Asian medicinal mushrooms that were formerly known as the " Inonotus linteus" complex. The structure elucidation of compounds 1-13, based on 2D NMR spectroscopy, high-resolution mass spectrometry, and other spectral methods, and their antibacterial, antifungal, and cytotoxic activities are reported.
- Published
- 2019
19. The amazing potential of fungi: 50 ways we can exploit fungi industrially
- Author
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Nimali I. de Silva, Rajesh Jeewon, Jake Winiski, Pattana Kakumyan, Marc Stadler, Jaturong Kumla, Jiye Yan, Ruvishika S. Jayawardena, Chayanard Phukhamsakda, Kanaporn Sujarit, Siraprapa Brooks, Achala R. Rathnayaka, Meghan O’Brien, Naritsada Thongklang, Eleni Gentekaki, Pranami D. Abeywickrama, Peter E. Mortimer, Dulanjalee Harishchandra, Peter Mueller, Nakarin Suwannarach, Thatsanee Luangharn, Kevin D. Hyde, Sylvie Rapior, Benjarong Thongbai, Thitipone Suwunwong, Karaba N. Nataraja, Jianchu Xu, Rashika S. Brahamanage, Craig B. Faulds, Hridya Hemachandran, Sehroon Khan, Samantha C. Karunarathna, Trichur S. Suryanarayanan, Sinang Hongsanan, Boontiya Chuankid, Birthe Sandargo, Ning-Guo Liu, Sadia Nadir, Janith V. S. Aluthmuhandiram, Mingkwan Doilom, Diana S. Marasinghe, Watsana Penkhrue, K. W. Thilini Chethana, Anuruddha Karunarathna, Venkat Gopalan, Allen Grace Niego, Resurreccion B. Sadaba, Clara Chepkirui, Putarak Chomnunti, Erandi Yasanthika, Uma Shaanker Ramanan, Danushka S. Tennakoon, Saisamorn Lumyong, Binu C. Samarakoon, Amornrat Chaiyasen, Sureeporn Nontachaiyapoom, Wasan Sriprom, Jian-Kui Liu, S. Nuwanthika Wijesinghe, Ramamoorthy Siva, Allan Patrick G. Macabeo, Dan Meeks, De-Ping Wei, Mae Fah Luang University [Thaïlande] (MFU), Kunming Institute of Botany [CAS] (KIB), Chinese Academy of Sciences [Beijing] (CAS), Centre d’Ecologie Fonctionnelle et Evolutive (CEFE), Université Paul-Valéry - Montpellier 3 (UPVM)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École Pratique des Hautes Études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Biodiversité et Biotechnologie Fongiques (BBF), Institut National de la Recherche Agronomique (INRA)-Aix Marseille Université (AMU)-École Centrale de Marseille (ECM), Faculty of Computer Science, Dalhousie University [Halifax], Institute of Excellence in Fungal Research and School of Science, German Centre for Infection Research (DZIF), XDB31000000, DBG6180015, 621C1535, DBG6180033, 2018PC0006, 256108A3070006, 41761144055 41771063 Y4ZK111B01, PHD57I0015, DBT-NER/Agri/24/2013, NAHEP/CAAST/2018-19, HZI,Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7,38124 Braunschweig, Germany., Centre National de la Recherche Scientifique (CNRS)-Université de Montpellier (UM)-École pratique des hautes études (EPHE), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Université Paul-Valéry - Montpellier 3 (UPVM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro), Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut de Recherche pour le Développement (IRD [France-Sud]), Kunming Institute of Botany, Institut de Recherche pour le Développement (IRD [France-Sud])-Centre National de la Recherche Scientifique (CNRS)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-Université Paul-Valéry - Montpellier 3 (UM3), École Centrale de Marseille (ECM)-Aix Marseille Université (AMU)-Institut National de la Recherche Agronomique (INRA), and Université Paul-Valéry - Montpellier 3 (UM3)-Institut National de la Recherche Agronomique (INRA)-Centre international d'études supérieures en sciences agronomiques (Montpellier SupAgro)-École pratique des hautes études (EPHE)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche pour le Développement (IRD [France-Sud])-Institut national d’études supérieures agronomiques de Montpellier (Montpellier SupAgro)
- Subjects
Fungal biodiversity ,Resource (biology) ,Biocontrôle ,Exploit ,Mushrooms ,[SDV]Life Sciences [q-bio] ,champignon ,Biotechnologies ,Biology ,biodiversité ,03 medical and health sciences ,application industrielle ,Mycology ,[CHIM]Chemical Sciences ,Ecology, Evolution, Behavior and Systematics ,Economic potential ,030304 developmental biology ,2. Zero hunger ,Biocontrol ,Biodiversity ,Biotechnology ,Food ,Fungi ,0303 health sciences ,Ecology ,030306 microbiology ,Agroforestry ,fungi ,biotechnologie alimentaire ,Flow chart ,[SDE]Environmental Sciences - Abstract
Fungi are an understudied, biotechnologically valuable group of organisms. Due to the immense range of habitats that fungi inhabit, and the consequent need to compete against a diverse array of other fungi, bacteria, and animals, fungi have developed numerous survival mechanisms. The unique attributes of fungi thus herald great promise for their application in biotechnology and industry. Moreover, fungi can be grown with relative ease, making production at scale viable. The search for fungal biodiversity, and the construction of a living fungi collection, both have incredible economic potential in locating organisms with novel industrial uses that will lead to novel products. This manuscript reviews fifty ways in which fungi can potentially be utilized as biotechnology. We provide notes and examples for each potential exploitation and give examples from our own work and the work of other notable researchers. We also provide a flow chart that can be used to convince funding bodies of the importance of fungi for biotechnological research and as potential products. Fungi have provided the world with penicillin, lovastatin, and other globally significant medicines, and they remain an untapped resource with enormous industrial potential. © 2019, The Author(s).
- Published
- 2019
20. Skeletocutins A-L: Antibacterial Agents from the Kenyan Wood-Inhabiting Basidiomycete, Skeletocutis sp
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Marc Stadler, Eike Steinmann, Dimas F. Praditya, Josphat C. Matasyoh, Winnie Chemutai Sum, Tian Cheng, Cony Decock, Clara Chepkirui, Kathrin Wittstein, and UCL - SST/ELI/ELIM - Applied Microbiology
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0106 biological sciences ,Bioassay guided fractionation ,010401 analytical chemistry ,Basidiomycota ,General Chemistry ,Biology ,Isolation (microbiology) ,biology.organism_classification ,01 natural sciences ,0104 chemical sciences ,Skeletocutis ,Botany ,Fungal strain ,Fermentation ,General Agricultural and Biological Sciences ,010606 plant biology & botany ,Polyporaceae - Abstract
Fermentation of the fungal strain Skeletocutis sp. originating from Mount Elgon Natural Reserve in Kenya, followed by bioassay guided fractionation led to the isolation of 12 previously undescribed metabolites named skeletocutins A-L (1–5 and 7–13) together with the known tyromycin A (6). Their structures were assigned by NMR spectroscopy complemented by HR-ESIMS. Compounds 1–6 and 11–13 exhibited selective activities against Gram-positive bacteria, while compound 10 weakly inhibited the formation of biofilm of Staphylococcus aureus. The isolated metabolites were also evaluated for inhibition of L-leucine aminopeptidase, since tyromycin A had previously been reported to possess such activities but only showed weak effects. Furthermore, all compounds were tested for antiviral activity against Hepatitis C virus (HCV), and compound 6 moderately inhibited HCV infectivity with an IC50 of 6.6 μM.
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- 2019
21. Biological and chemical diversity go hand in hand: Basidiomycota as source of new pharmaceuticals and agrochemicals
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Stephan Hüttel, Marc Stadler, Lillibeth Chaverra-Muñoz, Birthe Sandargo, Benjarong Thongbai, Tian Cheng, and Clara Chepkirui
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0106 biological sciences ,Asia ,Agrochemical ,Bioengineering ,01 natural sciences ,Applied Microbiology and Biotechnology ,Biotechnological process ,03 medical and health sciences ,Ascomycota ,010608 biotechnology ,Medicinal plants ,Organism ,030304 developmental biology ,0303 health sciences ,Bioprospecting ,Biological Products ,biology ,business.industry ,Basidiomycota ,biology.organism_classification ,Biotechnology ,Chemical diversity ,business ,Agrochemicals - Abstract
The Basidiomycota constitutes the second largest higher taxonomic group of the Fungi after the Ascomycota and comprises over 30.000 species. Mycelial cultures of Basidiomycota have already been studied since the 1950s for production of antibiotics and other beneficial secondary metabolites. Despite the fact that unique and selective compounds like pleuromutilin were obtained early on, it took several decades more until they were subjected to a systematic screening for antimicrobial and anticancer activities. These efforts led to the discovery of the strobilurins and several hundreds of further compounds that mainly constitute terpenoids. In parallel the traditional medicinal mushrooms of Asia were also studied intensively for metabolite production, aimed at finding new therapeutic agents for treatment of various diseases including metabolic disorders and the central nervous system. While the evaluation of this organism group has in general been more tedious as compared to the Ascomycota, the chances to discover new metabolites and to develop them further to candidates for drugs, agrochemicals and other products for the Life Science industry have substantially increased over the past decade. This is owing to the revolutionary developments in -OMICS techniques, bioinformatics, analytical chemistry and biotechnological process technology, which are steadily being developed further. On the other hand, the new developments in polythetic fungal taxonomy now also allow a more concise selection of previously untapped organisms. The current review is dedicated to summarize the state of the art and to give an outlook to further developments.
- Published
- 2018
22. An unprecedented spiro [furan-2,1’-indene]-3-one derivative and other nematicidal and antimicrobial metabolites from Sanghuangporus sp. (Hymenochaetaceae, Basidiomycota) collected in Kenya
- Author
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Cony Decock, Tian Cheng, Marc Stadler, Clara Chepkirui, Josphat C. Matasyoh, and Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7, 38124 Braunschweig, Germany.
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0301 basic medicine ,biology ,010405 organic chemistry ,Stereochemistry ,Basidiomycota ,Plant Science ,Hymenochaetaceae ,biology.organism_classification ,Antimicrobial ,01 natural sciences ,Biochemistry ,0104 chemical sciences ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,chemistry ,Furan ,Hispidin ,Indene ,Agronomy and Crop Science ,Sanghuangporus ,Derivative (chemistry) ,Biotechnology - Abstract
Bioassay guided fractionation of extracts derived from submerged cultures of a Sanghuangporus sp. (i.e., the genus that was until recently referred to as the “Inonotus linteus complex” of medicinal mushrooms) originating from Kenya led to the isolation of a new spiro [furan-2,1’-indine]-3-one derivative, for which we propose the trivial name phelligridin L (1) together with the known compounds 3,14′-bihispidinyl (2), hispidin (3), ionylideneacetic acid (4), 1S-(2E)-5-[(1R)-2,2-dimethyl-6-methylidenecyclohexyl]-3-methylpent-2-enoic acid (5), phellidine E (6) and phellidine D (7). Compounds 1–3, showed moderate nematicidal activity against Caenorhabditis elegans with LD50 of 12.5 μg/m. The nematicidal activity of 3, 14′-bihispidinyl and hispidin (1, 2) has not been reported before. Furthermore, compounds 1–5 demonstrated moderate antimicrobial activity against various test organisms.
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- 2018
23. The genus Diaporthe: a rich source of diverse and bioactive metabolites
- Author
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Marc Stadler, Clara Chepkirui, and Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr.17, 38124 Braunschweig, Germany.
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biology ,Ascomycota ,010405 organic chemistry ,Host (biology) ,biology.organism_classification ,01 natural sciences ,Agricultural and Biological Sciences (miscellaneous) ,Plant use of endophytic fungi in defense ,0104 chemical sciences ,010404 medicinal & biomolecular chemistry ,Taxon ,Diaporthe ,Phomopsis ,Genus ,Botany ,Medicinal plants ,Ecology, Evolution, Behavior and Systematics - Abstract
The genus Diaporthe (asexual state: Phomopsis) comprises pathogenic, endophytic and saprobic species with both temperate and tropical distributions. Although species of Diaporthe have in the past chiefly been distinguished based on host association, studies have confirmed several taxa to have wide host ranges, suggesting that they move freely between hosts, frequently co-colonizing diseased or dead tissue, while some species are known to be host-specific. They are also very frequently isolated as endophytes of seed plants. Due to their importance as plant pathogens, the genus has been thoroughly investigated for secondary metabolites, including during screening programs aimed at the discovery of novel bioactive natural products, but the respective information has never been compiled. Therefore, we have examined the relevant literature to explore and highlight the major classes of metabolites of Diaporthe and their Phomopsis conidial states. These fungi predominantly produce a large number of polyketides, but cytochalasins and other types of commonly encountered fungal secondary metabolites are also predominant in some species. Interestingly, not a single metabolite which is also known from the host plant has ever been isolated as a major component from an endophytic Diaporthe strain, despite the fact that many of the recent studies were targeting endophytic fungi of medicinal plants.
- Published
- 2017
24. Monochlorinated calocerins A-D and 9-oxostrobilurin derivatives from the basidiomycete Favolaschia calocera
- Author
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Christian Richter, Clara Chepkirui, Marc Stadler, Josphat C. Matasyoh, and Helmholtz Centre for infection research, Ihoffenstr. 7, 38124 Braunschweig, Germany.
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0301 basic medicine ,Antifungal ,Antifungal Agents ,Stereochemistry ,medicine.drug_class ,Plant Science ,Microbial Sensitivity Tests ,Horticulture ,Biology ,Biochemistry ,Strobilurin G ,Terpene ,03 medical and health sciences ,medicine ,Hydrocarbons, Chlorinated ,Humans ,Molecular Biology ,Mycelium ,Mycenaceae ,Benzofurans ,Favolaschia calocera ,Basidiomycota ,General Medicine ,Strobilurins ,biology.organism_classification ,Kenya ,Triterpenes ,030104 developmental biology ,Pterulinic acid ,Oxepins ,Fatty Acids, Unsaturated ,Methacrylates ,Drug Screening Assays, Antitumor - Abstract
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.
- Published
- 2016
25. Aethiopinolones A–E, New Pregnenolone Type Steroids from the East African Basidiomycete Fomitiporia aethiopica
- Author
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Tian Cheng, Josphat C. Matasyoh, Cony Decock, Winnie Chemutai Sum, Marc Stadler, Clara Chepkirui, and Helmholtz-Zentrum für Infektionsforschung GmbH, Inhoffenstr. 7, 38124 Braunschweig, Germany.
- Subjects
0301 basic medicine ,Cell Survival ,Secondary Metabolism ,Pharmaceutical Science ,Antineoplastic Agents ,Hymenochaetaceae ,01 natural sciences ,High-performance liquid chromatography ,Article ,Analytical Chemistry ,lcsh:QD241-441 ,Terpene ,Mice ,03 medical and health sciences ,lcsh:Organic chemistry ,Anti-Infective Agents ,triterpenes ,Cell Line, Tumor ,Drug Discovery ,medicine ,Animals ,Humans ,Physical and Theoretical Chemistry ,Mycelium ,Traditional medicine ,biology ,010405 organic chemistry ,Chemistry ,Basidiomycota ,Organic Chemistry ,Antimicrobial ,biology.organism_classification ,Triterpenes ,0104 chemical sciences ,030104 developmental biology ,Chemistry (miscellaneous) ,Cell culture ,Pregnenolone ,cytotoxicity ,Molecular Medicine ,fungi ,Fermentation ,Drug Screening Assays, Antitumor ,medicine.drug - Abstract
A mycelial culture of the Kenyan basidiomycete Fomitiporia aethiopica was fermented on rice and the cultures were extracted with methanol. Subsequent HPLC profiling and preparative chromatography of its crude extract led to the isolation of five previously undescribed pregnenolone type triterpenes 1–5, for which we propose the trivial name aethiopinolones A–E. The chemical structures of the aethiopinolones were determined by extensive 1D- and 2D-NMR, and HRMS data analysis. The compounds exhibited moderate cytotoxic effects against various human cancer cell lines, but they were found devoid of significant nematicidal and antimicrobial activities. View Full-Text
- Published
- 2018
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