1
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El-Elimat T, Figueroa M, Raja HA, Alnabulsi SM, Oberlies NH. Coumarins, dihydroisocoumarins, a dibenzo- α-pyrone, a meroterpenoid, and a merodrimane from Talaromyces amestolkiae. Tetrahedron Lett 2021; 72. [PMID: 34421136 DOI: 10.1016/j.tetlet.2021.153067] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Chemical investigation of an organic extract of a fungus isolated from submerged wood collected from fresh water (strain G173), identified as a Talaromyces amestolkiae (Eurotiales; Trichocomaceae), led to the isolation of three coumarins, three dihydroisocoumarins, a dibenzo-α-pyrone, a meroterpenoid, and a merodrimane. Three of the isolated compounds, namely 7-chloropestalasin A (3), 4-hydroxyaspergillumarin (6), and ent-thailandolide B (9) were new. The structures were elucidated using a combination of spectroscopic and spectrometric techniques. The absolute configurations of 2, 3, 5, and 6 were established via a modified Mosher's ester method, whereas for 9 a combination of TDDFT ECD and ORD calculations were employed. Compounds 1-9 were evaluated for antimicrobial activity against a group of bacteria and fungi.
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Affiliation(s)
- Tamam El-Elimat
- Department of Medicinal Chemistry and Pharmacognosy, Faculty of Pharmacy, Jordan University of Science and Technology, P.O. Box 3030, Irbid 22110, Jordan
| | - Mario Figueroa
- Facultad de Química, Universidad Nacional Autónoma de México, Ciudad de México 04510, México
| | - Huzefa A Raja
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, Greensboro, NC 27402, United States
| | - Soraya M Alnabulsi
- Department of Medicinal Chemistry and Pharmacognosy, Faculty of Pharmacy, Jordan University of Science and Technology, P.O. Box 3030, Irbid 22110, Jordan
| | - Nicholas H Oberlies
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, Greensboro, NC 27402, United States
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2
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McCone JAJ, Somarathne KK, Orme CL, Hewitt RJ, Grant ER, Hall KR, Ackerley DF, La Flamme AC, Harvey JE. Total Synthesis and Bioactivity Studies of Fungal Metabolite (-)-TAN-2483B. Org Lett 2020; 22:9427-9432. [PMID: 33232161 DOI: 10.1021/acs.orglett.0c03303] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The first total synthesis of (-)-TAN-2483B, a fungal metabolite possessing a densely functionalized furo[3,4-b]pyran-5-one framework, is achieved in 14 steps from d-mannose. Generation of the 2,6-trans-pyran is by cyclopropane ring expansion followed by α-selective alkynylation. Julia-Kocienski olefination introduces the E-propenyl side chain. Alkyne functionalization and carbonylation stereoselectively establish the bicyclic core of (-)-TAN-2483B. Inhibition of kinases Btk and Bmx, bacterial priority pathogens, and cytokine production in splenocytes indicates promising therapeutic potential.
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3
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A Revised Structure and Assigned Absolute Configuration of Theissenolactone A. Molecules 2020; 25:molecules25204823. [PMID: 33092217 PMCID: PMC7587954 DOI: 10.3390/molecules25204823] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 10/13/2020] [Accepted: 10/16/2020] [Indexed: 11/16/2022] Open
Abstract
Antimicrobial bioassay-guided fractionation of Microcera larvarum led to the isolation of a γ-lactone with a furo[3,4-b]pyran-5-one bicyclic ring system (1) and three known compounds, (3S,4R)-4-hydroxymellein (2), (3S,4S)-4-hydroxymellein (3) and 7-hydroxy-3-(1-hydroxyethyl)isobenzofuran-1(3H)-one (4). Structure elucidation was conducted by NMR spectroscopic methods. Absolute configuration of 1 (2R, 3S, 5S, 7S, 8R) was established using the chiral derivatizing agent MPA and was fully supported by calculated specific rotation and ECD spectra. The spectroscopic data observed for 1 were identical to those previously reported for theissenolactone A (7), necessitating a correction of the latter (from C-5/C-8 trans ring fusion to cis). Compounds 1–4 were evaluated for antimicrobial activity against a panel of pathogens.
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4
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Somarathne KK, McCone JAJ, Brackovic A, Rivera JLP, Fulton JR, Russell E, Field JJ, Orme CL, Stirrat HL, Riesterer J, Teesdale‐Spittle PH, Miller JH, Harvey JE. Synthesis of Bioactive Side‐Chain Analogues of TAN‐2483B. Chem Asian J 2019; 14:1230-1237. [DOI: 10.1002/asia.201801767] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Revised: 12/27/2018] [Indexed: 01/13/2023]
Affiliation(s)
- Kalpani K. Somarathne
- School of Chemical and Physical Sciences, Centre for BiodiscoveryVictoria University of Wellington Wellington New Zealand
| | - Jordan A. J. McCone
- School of Chemical and Physical Sciences, Centre for BiodiscoveryVictoria University of Wellington Wellington New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery Auckland New Zealand
| | - Amira Brackovic
- School of Chemical and Physical Sciences, Centre for BiodiscoveryVictoria University of Wellington Wellington New Zealand
| | - José Luis Pinedo Rivera
- School of Chemical and Physical Sciences, Centre for BiodiscoveryVictoria University of Wellington Wellington New Zealand
| | - J. Robin Fulton
- School of Chemical and Physical Sciences, Centre for BiodiscoveryVictoria University of Wellington Wellington New Zealand
| | - Euan Russell
- School of Biological Sciences, Centre for BiodiscoveryVictoria University of Wellington Wellington New Zealand
| | - Jessica J. Field
- School of Biological Sciences, Centre for BiodiscoveryVictoria University of Wellington Wellington New Zealand
| | - Christopher L. Orme
- School of Chemical and Physical Sciences, Centre for BiodiscoveryVictoria University of Wellington Wellington New Zealand
| | - Hedley L. Stirrat
- School of Chemical and Physical Sciences, Centre for BiodiscoveryVictoria University of Wellington Wellington New Zealand
| | - Jasmin Riesterer
- School of Chemical and Physical Sciences, Centre for BiodiscoveryVictoria University of Wellington Wellington New Zealand
| | - Paul H. Teesdale‐Spittle
- Maurice Wilkins Centre for Molecular Biodiscovery Auckland New Zealand
- School of Biological Sciences, Centre for BiodiscoveryVictoria University of Wellington Wellington New Zealand
| | - John H. Miller
- School of Biological Sciences, Centre for BiodiscoveryVictoria University of Wellington Wellington New Zealand
| | - Joanne E. Harvey
- School of Chemical and Physical Sciences, Centre for BiodiscoveryVictoria University of Wellington Wellington New Zealand
- Maurice Wilkins Centre for Molecular Biodiscovery Auckland New Zealand
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5
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Fan SQ, Xie CL, Xia JM, Xing CP, Luo ZH, Shao Z, Yan XJ, He S, Yang XW. Sarocladione, a unique 5,10:8,9-diseco-steroid from the deep-sea-derived fungusSarocladium kiliense. Org Biomol Chem 2019; 17:5925-5928. [DOI: 10.1039/c9ob01159e] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Sarocladione was isolated from the deep-sea-derived fungusSarocladium kilienseas the first example of a 5,10:8,9-diseco-steroid.
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Affiliation(s)
- Shao-Qiang Fan
- Li Dak Sum Yip Yio Chin Kenneth Li Marine Biopharmaceutical Research Center
- Ningbo University
- Ningbo 315211
- China
- Key Laboratory of Marine Biogenetic Resources
| | - Chun-Lan Xie
- Key Laboratory of Marine Biogenetic Resources
- Third Institute of Oceanography
- Ministry of Natural Resources
- Xiamen 361005
- China
| | - Jin-Mei Xia
- Key Laboratory of Marine Biogenetic Resources
- Third Institute of Oceanography
- Ministry of Natural Resources
- Xiamen 361005
- China
| | - Cui-Ping Xing
- Key Laboratory of Marine Biogenetic Resources
- Third Institute of Oceanography
- Ministry of Natural Resources
- Xiamen 361005
- China
| | - Zhu-Hua Luo
- Key Laboratory of Marine Biogenetic Resources
- Third Institute of Oceanography
- Ministry of Natural Resources
- Xiamen 361005
- China
| | - Zongze Shao
- Key Laboratory of Marine Biogenetic Resources
- Third Institute of Oceanography
- Ministry of Natural Resources
- Xiamen 361005
- China
| | - Xiao-Jun Yan
- Li Dak Sum Yip Yio Chin Kenneth Li Marine Biopharmaceutical Research Center
- Ningbo University
- Ningbo 315211
- China
| | - Shan He
- Li Dak Sum Yip Yio Chin Kenneth Li Marine Biopharmaceutical Research Center
- Ningbo University
- Ningbo 315211
- China
| | - Xian-Wen Yang
- Key Laboratory of Marine Biogenetic Resources
- Third Institute of Oceanography
- Ministry of Natural Resources
- Xiamen 361005
- China
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Brooks WC, Paguigan ND, Raja HA, Moy FJ, Cech NB, Pearce CJ, Oberlies NH. qNMR for profiling the production of fungal secondary metabolites. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2017; 55:670-676. [PMID: 28024162 PMCID: PMC5459663 DOI: 10.1002/mrc.4571] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Revised: 12/13/2016] [Accepted: 12/16/2016] [Indexed: 06/06/2023]
Abstract
Analysis of complex mixtures is a common challenge in natural products research. Quantitative nuclear magnetic resonance spectroscopy offers analysis of complex mixtures at early stages and with benefits that are orthogonal to more common methods of quantitation, including ultraviolet absorption spectroscopy and mass spectrometry. Several experiments were conducted to construct a methodology for use in analysis of extracts of fungal cultures. A broadly applicable method was sought for analysis of both pure and complex samples through use of an externally calibrated method. This method has the benefit of not contaminating valuable samples with the calibrant, and it passed scrutiny for line fitting and reproducibility. The method was implemented to measure the yield of griseofulvin and dechlorogriseofulvin from three fungal isolates. An isolate of Xylaria cubensis (coded MSX48662) was found to biosynthesize griseofulvin in the greatest yield, 149 ± 8 mg per fermentation, and was selected for further supply experiments. Copyright © 2016 John Wiley & Sons, Ltd.
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Affiliation(s)
- Wilson C. Brooks
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, P.O. Box 26170, Greensboro, North Carolina 27402, United States
| | - Noemi D. Paguigan
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, P.O. Box 26170, Greensboro, North Carolina 27402, United States
| | - Huzefa A. Raja
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, P.O. Box 26170, Greensboro, North Carolina 27402, United States
| | - Franklin J. Moy
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, P.O. Box 26170, Greensboro, North Carolina 27402, United States
| | - Nadja B. Cech
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, P.O. Box 26170, Greensboro, North Carolina 27402, United States
| | - Cedric J. Pearce
- Mycosynthetix, Inc., 505 Meadowland Drive, Suite 103, Hillsborough, North Carolina 27278, United States
| | - Nicholas H. Oberlies
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, P.O. Box 26170, Greensboro, North Carolina 27402, United States
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7
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Rivera-Chávez J, Raja HA, Graf TN, Burdette JE, Pearce CJ, Oberlies NH. Biosynthesis of Fluorinated Peptaibols Using a Site-Directed Building Block Incorporation Approach. JOURNAL OF NATURAL PRODUCTS 2017; 80:1883-1892. [PMID: 28594169 PMCID: PMC5485375 DOI: 10.1021/acs.jnatprod.7b00189] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2017] [Indexed: 05/20/2023]
Abstract
Synthetic biological approaches, such as site-directed biosynthesis, have contributed to the expansion of the chemical space of natural products, making possible the biosynthesis of unnatural metabolites that otherwise would be difficult to access. Such methods may allow the incorporation of fluorine, an atom rarely found in nature, into complex secondary metabolites. Organofluorine compounds and secondary metabolites have both played pivotal roles in the development of drugs; however, their discovery and development are often via nonintersecting tracks. In this context, we used the biosynthetic machinery of Trichoderma arundinaceum (strain MSX70741) to incorporate a fluorine atom into peptaibol-type molecules in a site-selective manner. Thus, fermentation of strain MSX70741 in media containing ortho- and meta-F-phenylalanine resulted in the biosynthesis of two new fluorine-containing alamethicin F50 derivatives. The fluorinated products were characterized using spectroscopic (1D and 2D NMR, including 19F) and spectrometric (HRESIMS/MSn) methods, and their absolute configurations were established by Marfey's analysis. Fluorine-containing alamethicin F50 derivatives exhibited potency analogous to the nonfluorinated parent when evaluated against a panel of human cancer cell lines. Importantly, the biosynthesis of fluorinated alamethicin F50 derivatives by strain MSX70741 was monitored in situ using a droplet-liquid microjunction-surface sampling probe coupled to a hyphenated system.
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Affiliation(s)
- José Rivera-Chávez
- Department
of Chemistry and Biochemistry, University
of North Carolina at Greensboro, P.O. Box 26170, Greensboro, North Carolina 27412, United States
| | - Huzefa A. Raja
- Department
of Chemistry and Biochemistry, University
of North Carolina at Greensboro, P.O. Box 26170, Greensboro, North Carolina 27412, United States
| | - Tyler N. Graf
- Department
of Chemistry and Biochemistry, University
of North Carolina at Greensboro, P.O. Box 26170, Greensboro, North Carolina 27412, United States
| | - Joanna E. Burdette
- Department
of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, Chicago, Illinois 60612, United States
| | - Cedric J. Pearce
- Mycosynthetix, Inc., 505 Meadowlands Drive, Suite 103, Hillsborough, North Carolina 27278, United States
| | - Nicholas H. Oberlies
- Department
of Chemistry and Biochemistry, University
of North Carolina at Greensboro, P.O. Box 26170, Greensboro, North Carolina 27412, United States
- E-mail: . Tel: 336-334-5474
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8
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Sal’nikova TV, Dmitriev MV, Maslivets AN. Synthesis of spiro[furo[3,4-b]pyran-4,3′-pyrroles] by reaction of pyrrolediones with malononitrile and tetronic acid. RUSSIAN JOURNAL OF ORGANIC CHEMISTRY 2017. [DOI: 10.1134/s1070428017010249] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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9
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α-Pyrone derivatives, tetra/hexahydroxanthones, and cyclodepsipeptides from two freshwater fungi. Bioorg Med Chem 2016; 25:795-804. [PMID: 27964996 DOI: 10.1016/j.bmc.2016.11.059] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2016] [Revised: 11/28/2016] [Accepted: 11/30/2016] [Indexed: 11/22/2022]
Abstract
Eighteen (1-18) and seven (1, 4, 6-8, 17 and 18) compounds were isolated from organic extracts of axenic cultures of two freshwater fungi Clohesyomyces sp. and Clohesyomyces aquaticus (Dothideomycetes, Ascomycota), respectively. Compounds 1-12 belong to the α-pyrone class of natural products, compounds 13 and 14 were tetrahydroxanthones, compounds 15 and 16 were hexahydroxanthones, while compounds 17 and 18 were cyclodepsipeptides. The structures were elucidated using a set of spectroscopic and spectrometric techniques. The absolute configurations of compounds 2, 3, 6, and 7 were assigned via a modified Mosher's ester method using 1H NMR data. The relative configurations of compounds 14-16 were determined through NOE data. Compounds 1, 2, 6, 8, 13, 14, and 15 were found to inhibit the essential enzyme bacterial peptidyl-tRNA hydrolase (Pth1), with (13; secalonic acid A) being the most potent. Compounds 1 and 4-18 were also evaluated for antimicrobial activity against an array of bacteria and fungi but were found to be inactive.
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10
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Abstract
AIM Fungi are valuable resources for bioactive secondary metabolites. However, the chemical space of fungal secondary metabolites has been studied only on a limited basis. Herein, we report a comprehensive chemoinformatic analysis of a unique set of 207 fungal metabolites isolated and characterized in a USA National Cancer Institute funded drug discovery project. RESULTS Comparison of the molecular complexity of the 207 fungal metabolites with approved anticancer and nonanticancer drugs, compounds in clinical studies, general screening compounds and molecules Generally Recognized as Safe revealed that fungal metabolites have high degree of complexity. Molecular fingerprints showed that fungal metabolites are as structurally diverse as other natural products and have, in general, drug-like physicochemical properties. CONCLUSION Fungal products represent promising candidates to expand the medicinally relevant chemical space. This work is a significant expansion of an analysis reported years ago for a smaller set of compounds (less than half of the ones included in the present work) from filamentous fungi using different structural properties.
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11
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Kaur A, Raja HA, Darveaux BA, Chen WL, Swanson SM, Pearce CJ, Oberlies NH. New diketopiperazine dimer from a filamentous fungal isolate of Aspergillus sydowii. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2015; 53:616-9. [PMID: 26040447 PMCID: PMC4692248 DOI: 10.1002/mrc.4254] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2015] [Revised: 03/31/2015] [Accepted: 04/06/2015] [Indexed: 05/23/2023]
Affiliation(s)
- Amninder Kaur
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, P.O. Box 26170, Greensboro, North Carolina 27402, United States
| | - Huzefa A. Raja
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, P.O. Box 26170, Greensboro, North Carolina 27402, United States
| | - Blaise A. Darveaux
- Mycosynthetix, Inc., 505 Meadowlands Drive, Suite 103, Hillsborough, North Carolina 27278, United States
| | - Wei-Lun Chen
- Department of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, Chicago, Illinois 60612, United States
| | - Steven M. Swanson
- Division of Pharmaceutical Sciences, School of Pharmacy, University of Wisconsin - Madison, Madison, WI, 53705, United States
| | - Cedric J. Pearce
- Mycosynthetix, Inc., 505 Meadowlands Drive, Suite 103, Hillsborough, North Carolina 27278, United States
| | - Nicholas H. Oberlies
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, P.O. Box 26170, Greensboro, North Carolina 27402, United States
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12
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Bussey RO, Kaur A, Todd DA, Egan JM, El-Elimat T, Graf TN, Raja HA, Oberlies NH, Cech NB. Comparison of the chemistry and diversity of endophytes isolated from wild-harvested and greenhouse-cultivated yerba mansa ( Anemopsis californica). PHYTOCHEMISTRY LETTERS 2015; 11:202-208. [PMID: 25642298 PMCID: PMC4307022 DOI: 10.1016/j.phytol.2014.12.013] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
With this study, we explored the identity and chemistry of fungal endophytes from the roots of yerba mansa [Anemopsis californica (Nutt.) Hook. & Arn. (Saururaceae)], a botanical traditionally used to treat infection. We compared the diversity of fungal endophytes isolated from a wild-harvested A. californica population, and those from plants cultivated for one year in a greenhouse environment. The wild-harvested population yielded thirteen fungal strains (eleven unique genotypes). Of the extracts prepared from these fungi, four inhibited growth of Staphylococcus aureus by >25% at 20 µg/mL, and three inhibited growth of Pseudomonas aeruginosa by ≥20% at 200 µg/mL. By comparison, A. californica roots after one year of cultivation in the greenhouse produced only two unique genotypes, neither of which displayed significant antimicrobial activity. The fungus Chaetomium cupreum isolated from wild-harvested A. californica yielded a new antimicrobial spirolactone, chaetocuprum (1). An additional fourteen known compounds were identified using LC-MS dereplication of the various fungal endophytes. This study provides new insights into the identity and chemistry of A. californica fungal endophytes, and demonstrates the importance of considering growing conditions when pursuing natural product drug discovery from endophytic fungi.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Nadja B. Cech
- Corresponding Author. ; phone 336-324-5011; fax 336-324-5402
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13
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El-Elimat T, Figueroa M, Raja HA, Graf TN, Swanson SM, Falkinham JO, Wani MC, Pearce CJ, Oberlies NH. Biosynthetically Distinct Cytotoxic Polyketides from Setophoma terrestris.. European J Org Chem 2015; 2015:109-121. [PMID: 25574154 PMCID: PMC4283843 DOI: 10.1002/ejoc.201402984] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2014] [Indexed: 11/09/2022]
Abstract
Sixteen polyketides belonging to diverse structural classes, including monomeric/dimeric tetrahydroxanthones and resorcylic acid lactones, were isolated from an organic extract of a fungal culture Setophoma terrestris (MSX45109) using bioactivity-directed fractionation as part of a search for anticancer leads from filamentous fungi. Of these, six were new: penicillixanthone B (5), blennolide H (6), 11-deoxy blennolide D (7), blennolide I (9), blennolide J (10), and pyrenomycin (16). The known compounds were: secalonic acid A (1), secalonic acid E (2), secalonic acid G (3), penicillixanthone A (4), paecilin B (8), aigialomycin A (11), hypothemycin (12), dihydrohypothemycin (13), pyrenochaetic acid C (14), and nidulalin B (15). The structures were elucidated using a set of spectroscopic and spectrometric techniques; the absolute configurations of compounds 1-10 were determined using ECD spectroscopy combined with time-dependent density functional theory (TDDFT) calculations, while a modified Mosher's ester method was used for compound 16. The cytotoxic activities of compounds (1-15) were evaluated using the MDA-MB-435 (melanoma) and SW-620 (colon) cancer cell lines. Compounds 1, 4, and 12 were the most potent with IC50 values ranging from 0.16 to 2.14 μM. When tested against a panel of bacteria and fungi, compounds 3 and 5 showed promising activity against the Gram-positive bacterium Micrococcus luteus with MIC values of 5 and 15 μg/mL, respectively.
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Affiliation(s)
- Tamam El-Elimat
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, Greensboro, NC 27402, United States, Homepage: http://www.uncg.edu/che/Group_Research_Page/NicholasOberlies
| | - Mario Figueroa
- Facultad de Química, Universidad Nacional Autónoma de México Mexico DF 04510, Mexico
| | - Huzefa A. Raja
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, Greensboro, NC 27402, United States, Homepage: http://www.uncg.edu/che/Group_Research_Page/NicholasOberlies
| | - Tyler N. Graf
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, Greensboro, NC 27402, United States, Homepage: http://www.uncg.edu/che/Group_Research_Page/NicholasOberlies
| | - Steven M. Swanson
- Department of Medicinal Chemistry and Pharmacognosy University of Illinois at Chicago, Chicago, IL 60612, United States
| | - Joseph O. Falkinham
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061, United States
| | - Mansukh C. Wani
- Natural Products Laboratory, Research Triangle Institute, Research Triangle Park NC 27709 United States
| | | | - Nicholas H. Oberlies
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, Greensboro, NC 27402, United States, Homepage: http://www.uncg.edu/che/Group_Research_Page/NicholasOberlies
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14
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3-epi-Waol A and Waol C: polyketide-derived γ-lactones isolated from the endophytic fungus Libertella blepharis F2644. Tetrahedron Lett 2015. [DOI: 10.1016/j.tetlet.2014.11.081] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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15
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El-Elimat T, Raja H, Day CS, Chen WL, Swanson SM, Oberlies NH. Greensporones: resorcylic acid lactones from an aquatic Halenospora sp. JOURNAL OF NATURAL PRODUCTS 2014; 77:2088-98. [PMID: 25093280 PMCID: PMC4176394 DOI: 10.1021/np500497r] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2014] [Indexed: 05/20/2023]
Abstract
Fourteen new resorcylic acid lactones (1-14) were isolated from an organic extract of a culture of a freshwater aquatic fungus Halenospora sp. originating from a stream in North Carolina. The structures were elucidated using a set of spectroscopic and spectrometric techniques. The absolute configuration of one representative member of the compounds (7) was assigned using X-ray crystallography of an analogue that incorporated a heavy atom, whereas for compounds 8-11, a modified Mosher's ester method was utilized. The relative configurations of compounds 12-14 were determined on the basis of NOE data. Compounds 12-14 were proposed as artifacts produced by intramolecular cycloetherification of the ε-hydroxy-α,β-unsaturated ketone moieties of the parent compounds during the purification processes. The isolated compounds, except for 8 and 12, were tested against the MDA-MB-435 (melanoma) and HT-29 (colon) cancer cell lines. Compound 5 was the most potent, with IC50 values of 2.9 and 7.5 μM, respectively. The compounds were evaluated as TAK1-TAB1 inhibitors but were found to be inactive.
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Affiliation(s)
- Tamam El-Elimat
- Department
of Chemistry and Biochemistry, University
of North Carolina at Greensboro, Greensboro, North Carolina 27402, United States
| | - Huzefa
A. Raja
- Department
of Chemistry and Biochemistry, University
of North Carolina at Greensboro, Greensboro, North Carolina 27402, United States
| | - Cynthia S. Day
- Department
of Chemistry, Wake Forest University, Winston-Salem, North Carolina 27109, United States
| | - Wei-Lun Chen
- Department
of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, Chicago, Illinois 60612, United States
| | - Steven M. Swanson
- Department
of Medicinal Chemistry and Pharmacognosy, University of Illinois at Chicago, Chicago, Illinois 60612, United States
| | - Nicholas H. Oberlies
- Department
of Chemistry and Biochemistry, University
of North Carolina at Greensboro, Greensboro, North Carolina 27402, United States
- Phone: 336-334-5474. E-mail:
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16
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Sorbicillinoid analogs with cytotoxic and selective anti-Aspergillus activities from Scytalidium album. J Antibiot (Tokyo) 2014; 68:191-6. [PMID: 25248727 PMCID: PMC4372511 DOI: 10.1038/ja.2014.125] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Revised: 07/14/2014] [Accepted: 07/18/2014] [Indexed: 11/08/2022]
Abstract
As part of an ongoing project to explore filamentous fungi for anticancer and antibiotic leads, eleven compounds were isolated and identified from an organic extract of the fungus Scytalidium album (MSX51631) using bioactivity-directed fractionation against human cancer cell lines. Of these, eight were a series of sorbicillinoid analogues (1–8), of which four were new [scalbucillin A (2), scalbucillin B (3), scalbucillin C (6), and scalbucillin D (8)], two were phthalides (9–10), and one was naphthalenone (11). Compounds (1–11) were tested in the MDA-MB-435 (melanoma) and SW-620 (colon) cancer cell lines. Compound 1 was the most potent with IC50 values of 1.5 and 0.5 μM, respectively, followed by compound 5, with IC50 values of 2.3 and 2.5 μM at 72 h. Compound 1 showed a 48-h IC50 value of 3.1 μM when tested against the lymphocytic leukemia cell line OSU-CLL, while the nearly identical compound 5 had almost no activity in this assay. Compounds 1 and 5 showed selective and equipotent activity against Aspergillus niger with minimum inhibitory concentration values of 0.05 and 0.04 μg/ml (0.20 and 0.16 μM), respectively. The in vitro hemolytic activity against sheep erythrocytes of compounds 1 and 5 was investigated and were found to provoke 10% hemolysis at 52.5 and 45.0 μg/ml, respectively, indicative of a promising safety factor.
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Diverse prieurianin-type limonoid derivatives from the fruits of Aphanamixis grandifolia and their absolute configuration determination. Tetrahedron 2014. [DOI: 10.1016/j.tet.2014.07.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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El-Elimat T, Raja HA, Figueroa M, Falkinham JO, Oberlies NH. Isochromenones, isobenzofuranone, and tetrahydronaphthalenes produced by Paraphoma radicina, a fungus isolated from a freshwater habitat. PHYTOCHEMISTRY 2014; 104:114-120. [PMID: 24833033 DOI: 10.1016/j.phytochem.2014.04.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2014] [Revised: 03/31/2014] [Accepted: 04/10/2014] [Indexed: 05/28/2023]
Abstract
Six isochromenones (1-6), clearanols F (5) and G (6), one isobenzofuranone (7), and two tetrahydronaphthalene derivatives (8 and radinaphthalenone (9)), were isolated and identified from a culture of the fungus Paraphoma radicina, which was isolated from submerged wood in a freshwater lake. Compounds 5, 6 and 9 were previously unknown. The structures were elucidated using a set of spectroscopic and spectrometric techniques; the absolute configurations of compounds 5 and 6 were determined by comparison of their experimental ECD measurements with values predicted by TDDFT calculations. Compounds 1-9 were evaluated for antimicrobial activity against an array of bacteria and fungi. The inhibitory activity of compound 4 against Staphylococcus aureus biofilm formation was evaluated.
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Affiliation(s)
- Tamam El-Elimat
- University of North Carolina at Greensboro, Department of Chemistry and Biochemistry, Greensboro, NC 27402, United States
| | - Huzefa A Raja
- University of North Carolina at Greensboro, Department of Chemistry and Biochemistry, Greensboro, NC 27402, United States
| | - Mario Figueroa
- Facultad de Química, Universidad Nacional Autónoma de México, Mexico DF 04510, Mexico
| | - Joseph O Falkinham
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, United States
| | - Nicholas H Oberlies
- University of North Carolina at Greensboro, Department of Chemistry and Biochemistry, Greensboro, NC 27402, United States.
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VanderMolen KM, Raja HA, El-Elimat T, Oberlies NH. Evaluation of culture media for the production of secondary metabolites in a natural products screening program. AMB Express 2013; 3:71. [PMID: 24342059 PMCID: PMC3917616 DOI: 10.1186/2191-0855-3-71] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2013] [Accepted: 12/11/2013] [Indexed: 11/10/2022] Open
Abstract
Variation in the growing environment can have significant impacts on the quantity and diversity of fungal secondary metabolites. In the industrial setting, optimization of growing conditions can lead to significantly increased production of a compound of interest. Such optimization becomes challenging in a drug-discovery screening situation, as the ideal conditions for one organism may induce poor metabolic diversity for a different organism. Here, the impact of different media types, including six liquid media and five solid media, on the secondary metabolite production of three fungal strains was examined in the context of the drug-discovery screening process. The relative production of marker compounds was used to evaluate the usefulness and reliability of each medium for the purpose of producing secondary metabolites.
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