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Zhong LF, Ling J, Luo LX, Yang CN, Liang X, Qi SH. Lecanicilliums A-F, Thiodiketopiperazine-Class Alkaloids from a Mangrove Sediment-Derived Fungus Lecanicillium kalimantanense. Mar Drugs 2023; 21:575. [PMID: 37999399 PMCID: PMC10672332 DOI: 10.3390/md21110575] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2023] [Revised: 10/21/2023] [Accepted: 10/24/2023] [Indexed: 11/25/2023] Open
Abstract
Six new thiodiketopiperazine-class alkaloids lecanicilliums A-F were isolated from the mangrove sediment-derived fungus Lecanicillium kalimantanense SCSIO41702, together with thirteen known analogues. Their structures were determined by spectroscopic analysis. The absolute configurations were determined by quantum chemical calculations. Electronic circular dichroism (ECD) spectra and the structure of Lecanicillium C were further confirmed by a single-crystal X-ray diffraction analysis. Lecanicillium A contained an unprecedented 6/5/6/5/7/6 cyclic system with a spirocyclic center at C-2'. Biologically, lecanicillium E, emethacin B, and versicolor A displayed significant cytotoxicity against human lung adenocarcinoma cell line H1975, with IC50 values of 7.2~16.9 μM, and lecanicillium E also showed antibacterial activity against four pathogens with MIC values of 10~40 μg/mL. Their structure-activity relationship is also discussed.
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Affiliation(s)
- Lin-Fang Zhong
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; (L.-F.Z.); (J.L.); (X.L.)
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Juan Ling
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; (L.-F.Z.); (J.L.); (X.L.)
| | - Lian-Xiang Luo
- The Marine Biomedical Research Institute, Guangdong Medical University, Zhanjiang 524023, China; (L.-X.L.); (C.-N.Y.)
| | - Chang-Nian Yang
- The Marine Biomedical Research Institute, Guangdong Medical University, Zhanjiang 524023, China; (L.-X.L.); (C.-N.Y.)
| | - Xiao Liang
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; (L.-F.Z.); (J.L.); (X.L.)
| | - Shu-Hua Qi
- CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China; (L.-F.Z.); (J.L.); (X.L.)
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2
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Ma Z, Zhou A, Xia C. Strategies for total synthesis of bispyrrolidinoindoline alkaloids. Nat Prod Rep 2022; 39:1015-1044. [PMID: 35297915 DOI: 10.1039/d1np00060h] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Covering up to 2021Complex cyclotryptamine alkaloids with a bispyrrolidino[2,3-b]indoline (BPI) skeleton are an intriguing family of natural products, exhibiting wide systematic occurrences, large structural diversity, and multiple biological activities. Based on their structural characteristics, BPI alkaloids can be classified into chimonanthine-type BPI alkaloids, BPI diketopiperazines, and BPI epipolythiodiketopiperazines. These intricate molecules have captivated great attention soon after their isolation and identification in the 1960s. Due to the structural complexity, the total synthesis of these cyclotryptamine alkaloids is challenging. Nevertheless, remarkable progress has been achieved in the last six decades; in particular, several methods have been successfully established for the construction of vicinal all-carbon quaternary stereocenters. In this review, the structural diversity and chemical synthesis of these BPI alkaloids were summarized. BPI alkaloids are mainly synthesized by the methods of oxidative dimerization, reductive dimerization, and alkylation of bisoxindole. The purpose of this review is to present overall strategies for assembling the BPI skeleton and efforts towards controlling the stereocenters.
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Affiliation(s)
- Zhixian Ma
- Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, and Yunnan University Library, Yunnan University, Kunming 650091, China.
| | - Ankun Zhou
- Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, and Yunnan University Library, Yunnan University, Kunming 650091, China.
| | - Chengfeng Xia
- Key Laboratory of Medicinal Chemistry for Natural Resource, Ministry of Education, and Yunnan University Library, Yunnan University, Kunming 650091, China.
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3
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The Toxic Mechanism of Gliotoxins and Biosynthetic Strategies for Toxicity Prevention. Int J Mol Sci 2021; 22:ijms222413510. [PMID: 34948306 PMCID: PMC8705807 DOI: 10.3390/ijms222413510] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 12/09/2021] [Accepted: 12/13/2021] [Indexed: 12/13/2022] Open
Abstract
Gliotoxin is a kind of epipolythiodioxopiperazine derived from different fungi that is characterized by a disulfide bridge. Gliotoxins can be biosynthesized by a gli gene cluster and regulated by a positive GliZ regulator. Gliotoxins show cytotoxic effects via the suppression the function of macrophage immune function, inflammation, antiangiogenesis, DNA damage by ROS production, peroxide damage by the inhibition of various enzymes, and apoptosis through different signal pathways. In the other hand, gliotoxins can also be beneficial with different doses. Low doses of gliotoxin can be used as an antioxidant, in the diagnosis and treatment of HIV, and as an anti-tumor agent in the future. Gliotoxins have also been used in the control of plant pathogens, including Pythium ultimum and Sclerotinia sclerotiorum. Thus, it is important to elucidate the toxic mechanism of gliotoxins. The toxic mechanism of gliotoxins and biosynthetic strategies to reduce the toxicity of gliotoxins and their producing strains are summarized in this review.
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Hwang JY, Chung B, Kwon OS, Park SC, Cho E, Oh DC, Shin J, Oh KB. Inhibitory Effects of Epipolythiodioxopiperazine Fungal Metabolites on Isocitrate Lyase in the Glyoxylate Cycle of Candida albicans. Mar Drugs 2021; 19:md19060295. [PMID: 34067454 PMCID: PMC8224697 DOI: 10.3390/md19060295] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 05/20/2021] [Accepted: 05/20/2021] [Indexed: 11/16/2022] Open
Abstract
Four epipolythiodioxopiperazine fungal metabolites (1-4) isolated from the sponge-derived Aspergillus quadrilineatus FJJ093 were evaluated for their capacity to inhibit isocitrate lyase (ICL) in the glyoxylate cycle of Candida albicans. The structures of these compounds were elucidated using spectroscopic techniques and comparisons with previously reported data. We found secoemestrin C (1) (an epitetrathiodioxopiperazine derivative) to be a potent ICL inhibitor, with an inhibitory concentration of 4.77 ± 0.08 μM. Phenotypic analyses of ICL-deletion mutants via growth assays with acetate as the sole carbon source demonstrated that secoemestrin C (1) inhibited C. albicans ICL. Semi-quantitative reverse-transcription polymerase chain reaction analyses indicated that secoemestrin C (1) inhibits ICL mRNA expression in C. albicans under C2-assimilating conditions.
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Affiliation(s)
- Ji-Yeon Hwang
- Natural Products Research Institute, College of Pharmacy, Seoul National University, Seoul 08826, Korea; (J.-Y.H.); (O.-S.K.); (S.C.P.); (D.-C.O.)
| | - Beomkoo Chung
- Department of Agricultural Biotechnology, College of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea; (B.C.); (E.C.)
| | - Oh-Seok Kwon
- Natural Products Research Institute, College of Pharmacy, Seoul National University, Seoul 08826, Korea; (J.-Y.H.); (O.-S.K.); (S.C.P.); (D.-C.O.)
| | - Sung Chul Park
- Natural Products Research Institute, College of Pharmacy, Seoul National University, Seoul 08826, Korea; (J.-Y.H.); (O.-S.K.); (S.C.P.); (D.-C.O.)
| | - Eunji Cho
- Department of Agricultural Biotechnology, College of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea; (B.C.); (E.C.)
| | - Dong-Chan Oh
- Natural Products Research Institute, College of Pharmacy, Seoul National University, Seoul 08826, Korea; (J.-Y.H.); (O.-S.K.); (S.C.P.); (D.-C.O.)
| | - Jongheon Shin
- Natural Products Research Institute, College of Pharmacy, Seoul National University, Seoul 08826, Korea; (J.-Y.H.); (O.-S.K.); (S.C.P.); (D.-C.O.)
- Correspondence: (J.S.); (K.-B.O.); Tel.: +82-2-880-2484 (J.S.); +82-2-880-4646 (K.-B.O.)
| | - Ki-Bong Oh
- Department of Agricultural Biotechnology, College of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Korea; (B.C.); (E.C.)
- Correspondence: (J.S.); (K.-B.O.); Tel.: +82-2-880-2484 (J.S.); +82-2-880-4646 (K.-B.O.)
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5
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Understanding the fundamental role of virulence determinants to combat Aspergillus fumigatus infections: exploring beyond cell wall. Mycol Prog 2021. [DOI: 10.1007/s11557-021-01677-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
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6
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Brown R, Priest E, Naglik JR, Richardson JP. Fungal Toxins and Host Immune Responses. Front Microbiol 2021; 12:643639. [PMID: 33927703 PMCID: PMC8076518 DOI: 10.3389/fmicb.2021.643639] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Accepted: 03/08/2021] [Indexed: 12/11/2022] Open
Abstract
Fungi are ubiquitous organisms that thrive in diverse natural environments including soils, plants, animals, and the human body. In response to warmth, humidity, and moisture, certain fungi which grow on crops and harvested foodstuffs can produce mycotoxins; secondary metabolites which when ingested have a deleterious impact on health. Ongoing research indicates that some mycotoxins and, more recently, peptide toxins are also produced during active fungal infection in humans and experimental models. A combination of innate and adaptive immune recognition allows the host to eliminate invading pathogens from the body. However, imbalances in immune homeostasis often facilitate microbial infection. Despite the wide-ranging effects of fungal toxins on health, our understanding of toxin-mediated modulation of immune responses is incomplete. This review will explore the current understanding of fungal toxins and how they contribute to the modulation of host immunity.
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Affiliation(s)
| | | | | | - Jonathan P. Richardson
- Centre for Host-Microbiome Interactions, Faculty of Dentistry, Oral & Craniofacial Sciences, King’s College London, London, United Kingdom
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7
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Boucher M, Jordan TW. Primary Impacts of the Fungal Toxin Sporidesmin on HepG2 Cells: Altered Cell Adhesion without Oxidative Stress or Cell Death. Toxins (Basel) 2021; 13:toxins13030179. [PMID: 33670922 PMCID: PMC7997482 DOI: 10.3390/toxins13030179] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 02/19/2021] [Accepted: 02/22/2021] [Indexed: 12/22/2022] Open
Abstract
The fungal metabolite sporidesmin is responsible for severe necrotizing inflammation of biliary tract and liver of livestock grazing on pasture containing spores of Pithomyces chartarum that synthesizes the toxin. The toxin is secreted into bile causing the erosion of the biliary epithelium accompanied by inflammation and damage to surrounding tissues. Toxicity has been suggested to be due to cycles of reduction and oxidation of sporidesmin leading to oxidative damage from the formation of reactive oxygen species. The current work is the first test of the oxidative stress hypothesis using cultured cells. Oxidative stress could not be detected in HepG2 cells incubated with sporidesmin using a dichlorodihydrofluorescein diacetate assay or by use of two-dimensional electrophoresis to search for oxidized peroxiredoxins. There was also no evidence for necrosis or apoptosis, although there was a loss of cell adhesion that was accompanied by the disruption of intracellular actin microfilaments that have known roles in cell adhesion. The results are consistent with a model in which altered contact between cells in situ leads to altered permeability and subsequent inflammation and necrosis, potentially from the leakage of toxic bile into surrounding tissues. There is now a need for the further characterization of the damage processes in vivo, including the investigation of altered permeability and mechanisms of cell death in the biliary tract and other affected organs.
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Affiliation(s)
- Magalie Boucher
- Centre for Biodiscovery and School of Biological Sciences, Victoria University of Wellington, Wellington PO Box 600, New Zealand;
- Drug Safety Research and Development, Pfizer Inc., Cambridge, MA 02139, USA
| | - T. William Jordan
- Centre for Biodiscovery and School of Biological Sciences, Victoria University of Wellington, Wellington PO Box 600, New Zealand;
- Correspondence:
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Zhu M, Zhang X, Huang X, Wang H, Anjum K, Gu Q, Zhu T, Zhang G, Li D. Irregularly Bridged Epipolythiodioxopiperazines and Related Analogues: Sources, Structures, and Biological Activities. JOURNAL OF NATURAL PRODUCTS 2020; 83:2045-2053. [PMID: 32543845 DOI: 10.1021/acs.jnatprod.9b01283] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Epipolythiodioxopiperazines (ETPs) are a class of biologically active fungal secondary metabolites characterized by a bridged polysulfide piperazine ring. Regularly, the sulfide functionality is attached in the α-positions of the dioxopiperazine scaffold. However, ETPs possessing irregular sulfur bridges have rarely been explored. This review summarizes that 83 compounds of this subtype have been isolated and characterized since the discovery of gliovirin in 1982. Herein, particular emphasis is given to the isolation, chemistry, and biological activity of this subtype. For a better understanding, a relevant summary focusing on the source microorganisms and their taxonomy is provided and will help elucidate the fascinating chemistry and biology of these unusual ETPs.
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Affiliation(s)
- Meilin Zhu
- School of Pharmacy, Bengbu Medical College, 2600 Donghai Road, Bengbu 233030, Anhui, People's Republic of China
| | - Xuewen Zhang
- School of Pharmacy, Bengbu Medical College, 2600 Donghai Road, Bengbu 233030, Anhui, People's Republic of China
| | - Xuenan Huang
- School of Pharmacy, Bengbu Medical College, 2600 Donghai Road, Bengbu 233030, Anhui, People's Republic of China
| | - Haotian Wang
- School of Pharmacy, Bengbu Medical College, 2600 Donghai Road, Bengbu 233030, Anhui, People's Republic of China
| | - Komal Anjum
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, People's Republic of China
| | - Qianqun Gu
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, People's Republic of China
| | - Tianjiao Zhu
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, People's Republic of China
| | - Guojian Zhang
- Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, People's Republic of China
| | - Dehai Li
- Key Laboratory of Marine Drugs, Chinese Ministry of Education, School of Medicine and Pharmacy, Ocean University of China, Qingdao 266003, People's Republic of China
- Laboratory for Marine Drugs and Bioproducts of Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, People's Republic of China
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9
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Abstract
The fungal metabolite sporidesmin is responsible for the hepatogenous photosensitising disease facial eczema in livestock. Toxicity is due to a sulfur-bridged epidithiodioxopiperazine ring that has wide biological reactivity. The ways in which the toxin causes hepatobiliary and other tissue damage have not been established. Hypotheses include direct interaction with cellular thiols including protein cysteine residues or production of reactive oxygen species resulting in oxidative stress. Comparison with the cellular effects of the structurally related compound gliotoxin suggests additional mechanisms including interaction with cell adhesion complexes and possible downstream consequences for regulated necrosis as a response to tissue injury. Revision of hypotheses of how sporidesmin affects cells has the potential to generate new strategies for control of facial eczema including through identification of proteins and genes that are associated with resistance to the disease.
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Affiliation(s)
- T W Jordan
- School of Biological Sciences, Victoria University of Wellington, Wellington, New Zealand
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10
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Secondary Metabolites from the Culture of the Marine-derived Fungus Paradendryphiella salina PC 362H and Evaluation of the Anticancer Activity of Its Metabolite Hyalodendrin. Mar Drugs 2020; 18:md18040191. [PMID: 32260204 PMCID: PMC7230232 DOI: 10.3390/md18040191] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2019] [Revised: 03/30/2020] [Accepted: 03/31/2020] [Indexed: 12/24/2022] Open
Abstract
High-throughput screening assays have been designed to identify compounds capable of inhibiting phenotypes involved in cancer aggressiveness. However, most studies used commercially available chemical libraries. This prompted us to explore natural products isolated from marine-derived fungi as a new source of molecules. In this study, we established a chemical library from 99 strains corresponding to 45 molecular operational taxonomic units and evaluated their anticancer activity against the MCF7 epithelial cancer cell line and its invasive stem cell-like MCF7-Sh-WISP2 counterpart. We identified the marine fungal Paradendryphiella salina PC 362H strain, isolated from the brown alga Pelvetia caniculata (PC), as one of the most promising fungi which produce active compounds. Further chemical and biological characterizations of the culture of the Paradendryphiella salina PC 362H strain identified (-)-hyalodendrin as the active secondary metabolite responsible for the cytotoxic activity of the crude extract. The antitumor activity of (-)-hyalodendrin was not only limited to the MCF7 cell lines, but also prominent on cancer cells with invasive phenotypes including colorectal cancer cells resistant to chemotherapy. Further investigations showed that treatment of MCF7-Sh-WISP2 cells with (-)-hyalodendrin induced changes in the phosphorylation status of p53 and altered expression of HSP60, HSP70 and PRAS40 proteins. Altogether, our study reveals that this uninvestigated marine fungal crude extract possesses a strong therapeutic potential against tumor cells with aggressive phenotypes and confirms that members of the epidithiodioxopiperazines are interesting fungal toxins with anticancer activities.
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11
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Olsson CR, Payette JN, Cheah JH, Movassaghi M. Synthesis of Potent Cytotoxic Epidithiodiketopiperazines Designed for Derivatization. J Org Chem 2020; 85:4648-4662. [PMID: 32126173 PMCID: PMC7127967 DOI: 10.1021/acs.joc.9b03371] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We describe our design, synthesis, and chemical study of a set of functional epidithiodiketopiperazines (ETPs) and evaluation of their activity against five human cancer cell lines. Our structure-activity relationship-guided substitution of ETP alkaloids offers versatile derivatization while maintaining potent anticancer activity, offering exciting opportunity for their use as there are no examples of complex and potently anticancer (nM) ETPs being directly used as conjugatable probes or warheads. Our synthetic solutions to strategically designed ETPs with functional linkers required advances in stereoselective late-stage oxidation and thiolation chemistry in complex settings, including the application of novel reagents for dihydroxylation and cis-sulfidation of diketopiperazines. We demonstrate that complex ETPs equipped with a strategically substituted azide functional group are readily derivatized to the corresponding ETP-triazoles without compromising anticancer activity. Our chemical stability studies of ETPs along with cytotoxic evaluation of our designed ETPs against A549, DU 145, HeLa, HCT 116, and MCF7 human cancer cell lines provide insights into the impact of structural features on potency and chemical stability, informing future utility of ETPs in chemical and biological studies.
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Affiliation(s)
- Chase R Olsson
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Joshua N Payette
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Jaime H Cheah
- The Koch Institute for Integrative Cancer Research, Massachusetts Institute of Technology, 500 Main Street, Cambridge, Massachusetts 02139, United States
| | - Mohammad Movassaghi
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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12
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Gomes NGM, Pereira RB, Andrade PB, Valentão P. Double the Chemistry, Double the Fun: Structural Diversity and Biological Activity of Marine-Derived Diketopiperazine Dimers. Mar Drugs 2019; 17:md17100551. [PMID: 31569621 PMCID: PMC6835637 DOI: 10.3390/md17100551] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2019] [Revised: 09/22/2019] [Accepted: 09/25/2019] [Indexed: 12/14/2022] Open
Abstract
While several marine natural products bearing the 2,5-diketopiperazine ring have been reported to date, the unique chemistry of dimeric frameworks appears to remain neglected. Frequently reported from marine-derived strains of fungi, many naturally occurring diketopiperazine dimers have been shown to display a wide spectrum of pharmacological properties, particularly within the field of cancer and antimicrobial therapy. While their structures illustrate the unmatched power of marine biosynthetic machinery, often exhibiting unsymmetrical connections with rare linkage frameworks, enhanced binding ability to a variety of pharmacologically relevant receptors has been also witnessed. The existence of a bifunctional linker to anchor two substrates, resulting in a higher concentration of pharmacophores in proximity to recognition sites of several receptors involved in human diseases, portrays this group of metabolites as privileged lead structures for advanced pre-clinical and clinical studies. Despite the structural novelty of various marine diketopiperazine dimers and their relevant bioactive properties in several models of disease, to our knowledge, this attractive subclass of compounds is reviewed here for the first time.
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Affiliation(s)
- Nelson G M Gomes
- REQUIMTE/LAQV, Laboratório de Farmacognosia, Departamento de Química, Faculdade de Farmácia, Universidade do Porto, R. Jorge Viterbo Ferreira, nº 228, Porto 4050-313, Portugal.
| | - Renato B Pereira
- REQUIMTE/LAQV, Laboratório de Farmacognosia, Departamento de Química, Faculdade de Farmácia, Universidade do Porto, R. Jorge Viterbo Ferreira, nº 228, Porto 4050-313, Portugal.
| | - Paula B Andrade
- REQUIMTE/LAQV, Laboratório de Farmacognosia, Departamento de Química, Faculdade de Farmácia, Universidade do Porto, R. Jorge Viterbo Ferreira, nº 228, Porto 4050-313, Portugal.
| | - Patrícia Valentão
- REQUIMTE/LAQV, Laboratório de Farmacognosia, Departamento de Química, Faculdade de Farmácia, Universidade do Porto, R. Jorge Viterbo Ferreira, nº 228, Porto 4050-313, Portugal.
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13
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Snaddon TN, Scaggs TD, Pearson CM, Fyfe JWB. A Modular Construction of Epidithiodiketopiperazines. Org Lett 2019; 21:4873-4877. [PMID: 31184903 DOI: 10.1021/acs.orglett.9b01770] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Epidithiodiketopiperazines (ETPs) possess remarkably diverse biological activities and have attracted significant synthetic attention. The preparation of analogues is actively pursued; however, they are structurally challenging, and more direct and modular methods for their synthesis are desirable. To this end, the utility of a bifunctional triketopiperazine building block for the straightforward synthesis of ETPs is reported. A modular strategy consisting of enolate alkylation followed by site-selective nucleophile addition enables the concise synthesis of (±)-hyalodendrin and a range of analogues.
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Affiliation(s)
- Thomas N Snaddon
- Department of Chemistry , Indiana University , 800 East Kirkwood Avenue , Bloomington , Indiana 47405 , United States
| | - Toya D Scaggs
- Department of Chemistry , Indiana University , 800 East Kirkwood Avenue , Bloomington , Indiana 47405 , United States
| | - Colin M Pearson
- Department of Chemistry , Indiana University , 800 East Kirkwood Avenue , Bloomington , Indiana 47405 , United States
| | - James W B Fyfe
- Department of Chemistry , Indiana University , 800 East Kirkwood Avenue , Bloomington , Indiana 47405 , United States
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14
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Heravi MM, Zadsirjan V, Saedi P, Momeni T. Applications of Friedel-Crafts reactions in total synthesis of natural products. RSC Adv 2018; 8:40061-40163. [PMID: 35558228 PMCID: PMC9091380 DOI: 10.1039/c8ra07325b] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2018] [Accepted: 11/03/2018] [Indexed: 12/17/2022] Open
Abstract
Over the years, Friedel-Crafts (FC) reactions have been acknowledged as the most useful and powerful synthetic tools for the construction of a special kind of carbon-carbon bond involving an aromatic moiety. Its stoichiometric and, more recently, its catalytic procedures have extensively been studied. This reaction in recent years has frequently been used as a key step (steps) in the total synthesis of natural products and targeted complex bioactive molecules. In this review, we try to underscore the applications of intermolecular and intramolecular FC reactions in the total syntheses of natural products and complex molecules, exhibiting diverse biological properties.
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Affiliation(s)
- Majid M Heravi
- Department of Chemistry, School of Science, Alzahra University Vanak Tehran Iran +98 2188041344 +98 9121329147
| | - Vahideh Zadsirjan
- Department of Chemistry, School of Science, Alzahra University Vanak Tehran Iran +98 2188041344 +98 9121329147
| | - Pegah Saedi
- Department of Chemistry, School of Science, Alzahra University Vanak Tehran Iran +98 2188041344 +98 9121329147
| | - Tayebeh Momeni
- Department of Chemistry, School of Science, Alzahra University Vanak Tehran Iran +98 2188041344 +98 9121329147
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15
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Reece E, Doyle S, Greally P, Renwick J, McClean S. Aspergillus fumigatus Inhibits Pseudomonas aeruginosa in Co-culture: Implications of a Mutually Antagonistic Relationship on Virulence and Inflammation in the CF Airway. Front Microbiol 2018; 9:1205. [PMID: 29922270 PMCID: PMC5996130 DOI: 10.3389/fmicb.2018.01205] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2017] [Accepted: 05/17/2018] [Indexed: 11/26/2022] Open
Abstract
Many cystic fibrosis (CF) airway infections are considered to be polymicrobial and microbe–microbe interactions may play an important role in disease pathology. Pseudomonas aeruginosa and Aspergillus fumigatus are the most prevalent bacterial and fungal pathogens isolated from the CF airway, respectively. We have previously shown that patients co-colonized with these pathogens had comparable outcomes to those chronically colonized with P. aeruginosa. Our objective was to examine the interactions between A. fumigatus and P. aeruginosa, specifically the effects of co-colonization on biofilm formation, virulence and host pro-inflammatory responses. Our findings suggest that co-infections of A. fumigatus and P. aeruginosa in the Galleria mellonella acute infection model showed that pre-exposure of larvae to sub-lethal inocula of A. fumigatus increased the mortality caused by subsequent P. aeruginosa infection. Co-infection of human bronchial epithelial cells (CFBE41o-) with both pathogens did not enhance IL-6 and IL-8 production beyond the levels observed following single infections. In addition, both pathogens stimulated cytokine secretion via the same two mitogen-activated protein kinases (MAPKs) signaling pathways, ERK and p38. Mixed species biofilms showed overall reduced biofilm development with crystal violet staining. Quantification by species-specific qPCR revealed that both pathogens had mutually antagonistic effects on each other. A. fumigatus supernatants showed strong anti-Pseudomonal activity and gliotoxin was the main active agent. Gliotoxin resulted in varying levels of anti-biofilm activity toward other bacteria commonly found in the CF airways. Gliotoxin produced by A. fumigatus colonizing the CF airways may have a significant impact on the CF airway microbiome composition with potential clinical implications.
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Affiliation(s)
- Emma Reece
- Department of Clinical Microbiology, Trinity College Dublin - Trinity Centre for Health Science, Tallaght Hospital, Dublin, Ireland
| | - Sean Doyle
- Department of Biology, Maynooth University, Maynooth, Ireland
| | - Peter Greally
- Department of Respiratory Medicine, The National Children's Hospital, Tallaght Hospital, Dublin, Ireland
| | - Julie Renwick
- Department of Clinical Microbiology, Trinity College Dublin - Trinity Centre for Health Science, Tallaght Hospital, Dublin, Ireland
| | - Siobhán McClean
- School of Biomolecular and Biomedical Science, University College Dublin, Dublin, Ireland
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16
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Hodges TR, Benjamin NM, Martin SF. Concise approach to the syntheses of (±)-gliocladin C and related diketopiperazine alkaloids. Tetrahedron 2018. [DOI: 10.1016/j.tet.2018.04.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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17
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Affiliation(s)
| | | | - Stephen F. Martin
- Department
of Chemistry, The University of Texas, Austin, Texas 78712, United States
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18
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Wilkins SE, Abboud MI, Hancock RL, Schofield CJ. Targeting Protein-Protein Interactions in the HIF System. ChemMedChem 2016; 11:773-86. [PMID: 26997519 PMCID: PMC4848768 DOI: 10.1002/cmdc.201600012] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2016] [Revised: 02/24/2016] [Indexed: 12/18/2022]
Abstract
Animals respond to chronic hypoxia by increasing the levels of a transcription factor known as the hypoxia-inducible factor (HIF). HIF upregulates multiple genes, the products of which work to ameliorate the effects of limited oxygen at cellular and systemic levels. Hypoxia sensing by the HIF system involves hydroxylase-catalysed post-translational modifications of the HIF α-subunits, which 1) signal for degradation of HIF-α and 2) limit binding of HIF to transcriptional coactivator proteins. Because the hypoxic response is relevant to multiple disease states, therapeutic manipulation of the HIF-mediated response has considerable medicinal potential. In addition to modulation of catalysis by the HIF hydroxylases, the HIF system manifests other possibilities for therapeutic intervention involving protein-protein and protein-nucleic acid interactions. Recent advances in our understanding of the structural biology and biochemistry of the HIF system are facilitating medicinal chemistry efforts. Herein we give an overview of the HIF system, focusing on structural knowledge of protein-protein interactions and how this might be used to modulate the hypoxic response for therapeutic benefit.
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Affiliation(s)
- Sarah E Wilkins
- Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK.
| | - Martine I Abboud
- Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK
| | - Rebecca L Hancock
- Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK
| | - Christopher J Schofield
- Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK.
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19
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Szulc BR, Sil BC, Ruiz A, Hilton ST. A Common Precursor Approach to Structurally Diverse Natural Products: The Synthesis of the Core Structure of (±)-Clausenamide and the Total Synthesis of (±)-Hyalodendrin. European J Org Chem 2015. [DOI: 10.1002/ejoc.201501256] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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20
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Zipfel HF, Carreira EM. A Unified Strategy to 6-5-6-5-6-Membered Epipolythiodiketopiperazines: Studies towards the Total Synthesis of Scabrosin Diacetate and Haematocin. Chemistry 2015; 21:12475-80. [PMID: 26179159 DOI: 10.1002/chem.201500918] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2015] [Indexed: 11/11/2022]
Abstract
The family of epipolythiodiketopiperazine (ETP) natural products consists of over 200 members possessing a wide diversity of structures and biological activity. Recently, the subgroup of 6-5-6-5-6-membered ETPs has gained substantial attention, which has resulted in several total syntheses. Despite all the efforts that have been invested into accessing these complex structures, no synthesis of scabrosin diacetate (1 a) and its related esters has been reported. Herein, our attempts towards scabrosin diacetate (1 a) and haematocin (3) starting from diketopiperazine 12 a as a late-stage intermediate are presented. Diketopiperazine 12 a can be conveniently accessed in multigram quantities from aldehyde 18 and diketopiperazine 21 and was envisioned to serve as a general platform for the synthesis of 6-5-6-5-6-membered ETPs.
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Affiliation(s)
- Hannes F Zipfel
- Laboratorium für Organische Chemie, Eidgenössische Technische Hochschule Zürich, Vladimir-Prelog-Weg 3, 8093 Zürich (Switzerland)
| | - Erick M Carreira
- Laboratorium für Organische Chemie, Eidgenössische Technische Hochschule Zürich, Vladimir-Prelog-Weg 3, 8093 Zürich (Switzerland).
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21
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Resistance is not futile: gliotoxin biosynthesis, functionality and utility. Trends Microbiol 2015; 23:419-28. [PMID: 25766143 DOI: 10.1016/j.tim.2015.02.005] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2014] [Revised: 02/02/2015] [Accepted: 02/17/2015] [Indexed: 12/27/2022]
Abstract
Gliotoxin biosynthesis is encoded by the gli gene cluster in Aspergillus fumigatus. The biosynthesis of gliotoxin is influenced by a suite of transcriptionally-active regulatory proteins and a bis-thiomethyltransferase. A self-protection system against gliotoxin is present in A. fumigatus. Several additional metabolites are also produced via the gliotoxin biosynthetic pathway. Moreover, the biosynthesis of unrelated natural products appears to be influenced either by gliotoxin or by the activity of specific reactions within the biosynthetic pathway. The activity of gliotoxin against animal cells and fungi, often mediated by interference with redox homeostasis or protein modification, is revealing new metabolic interactions within eukaryotic systems. Nature has provided a most useful natural product with which to reveal some of its many molecular secrets.
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22
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Welch TR, Williams RM. Epidithiodioxopiperazines. occurrence, synthesis and biogenesis. Nat Prod Rep 2014; 31:1376-404. [PMID: 24816491 DOI: 10.1039/c3np70097f] [Citation(s) in RCA: 101] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Epidithiodioxopiperazine alkaloids possess an astonishing array of molecular architecture and generally exhibit potent biological activity. Nearly twenty distinct families have been isolated and characterized since the seminal discovery of gliotoxin in 1936. Numerous biosynthetic investigations offer a glimpse at the relative ease with which Nature is able to assemble this class of molecules, while providing synthetic chemists inspiration for the development of more efficient syntheses. Herein, we discuss the isolation and characterization, proposed fungal biogeneses, and total syntheses of epidithiodioxopiperazines.
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Affiliation(s)
- Timothy R Welch
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, USA.
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23
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Chankhamjon P, Boettger-Schmidt D, Scherlach K, Urbansky B, Lackner G, Kalb D, Dahse HM, Hoffmeister D, Hertweck C. Biosynthesis of the Halogenated Mycotoxin Aspirochlorine in Koji Mold Involves a Cryptic Amino Acid Conversion. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201407624] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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24
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Chankhamjon P, Boettger-Schmidt D, Scherlach K, Urbansky B, Lackner G, Kalb D, Dahse HM, Hoffmeister D, Hertweck C. Biosynthesis of the halogenated mycotoxin aspirochlorine in koji mold involves a cryptic amino acid conversion. Angew Chem Int Ed Engl 2014; 53:13409-13. [PMID: 25302411 DOI: 10.1002/anie.201407624] [Citation(s) in RCA: 76] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Indexed: 12/13/2022]
Abstract
Aspirochlorine (1) is an epidithiodiketopiperazine (ETP) toxin produced from koji mold (Aspergillus oryzae), which has been used in the oriental cuisine for over two millennia. Considering its potential risk for food safety, we have elucidated the molecular basis of aspirochlorine biosynthesis. By a combination of genetic and chemical analyses we found the acl gene locus and identified the key role of AclH as a chlorinase. Stable isotope labeling, biotransformation, and mutational experiments, analysis of intermediates and an in vitro adenylation domain assay gave totally unexpected insights into the acl pathway: Instead of one Phe and one Gly, two Phe units are assembled by an iterative non-ribosomal peptide synthetase (NRPS, AclP), followed by halogenation and an unprecedented Phe to Gly amino acid conversion. Biological assays showed that both amino acid transformations are required to confer cytotoxicity and antifungal activity to the mycotoxin.
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Affiliation(s)
- Pranatchareeya Chankhamjon
- Leibniz Institute for Natural Product Chemistry and Infection Biology, Departments Biomolecular Chemistry and Infection Biology, Beutenbergstr. 11a, 07745 Jena (Germany) http://www.hki-jena.de
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25
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Cherblanc FL, Chapman KL, Reid J, Borg AJ, Sundriyal S, Alcazar-Fuoli L, Bignell E, Demetriades M, Schofield CJ, DiMaggio PA, Brown R, Fuchter MJ. On the Histone Lysine Methyltransferase Activity of Fungal Metabolite Chaetocin. J Med Chem 2013; 56:8616-25. [DOI: 10.1021/jm401063r] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Affiliation(s)
- Fanny L. Cherblanc
- Department
of Chemistry, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
| | - Kathryn L. Chapman
- Mechanism
and Functional Screening Facility, Department of Surgery and Cancer, Imperial College London, Hammersmith Hospital Campus, London W12
ONN, United Kingdom
| | - Jim Reid
- Domainex
Ltd., 162 Cambridge Science
Park, Milton Road, Cambridge CB4 0GH, United Kingdom
| | - Aaron J. Borg
- Department
of Chemical Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
| | - Sandeep Sundriyal
- Department
of Chemistry, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
| | - Laura Alcazar-Fuoli
- Centre
for Molecular Microbiology and Infection, Imperial College London, Armstrong Road, London SW7 2AZ, United Kingdom
| | - Elaine Bignell
- Centre
for Molecular Microbiology and Infection, Imperial College London, Armstrong Road, London SW7 2AZ, United Kingdom
| | - Marina Demetriades
- Department
of Chemistry and the Oxford Centre for Integrative Systems Biology, Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Christopher J. Schofield
- Department
of Chemistry and the Oxford Centre for Integrative Systems Biology, Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, United Kingdom
| | - Peter A. DiMaggio
- Department
of Chemical Engineering, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
| | - Robert Brown
- Ovarian
Cancer Action Research Centre, Department of Surgery and Cancer, Imperial College London, Hammersmith Hospital Campus, London W12
ONN, United Kingdom
| | - Matthew J. Fuchter
- Department
of Chemistry, Imperial College London, South Kensington Campus, London SW7 2AZ, United Kingdom
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26
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Gu B, He S, Yan X, Zhang L. Tentative biosynthetic pathways of some microbial diketopiperazines. Appl Microbiol Biotechnol 2013; 97:8439-53. [DOI: 10.1007/s00253-013-5175-4] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2013] [Revised: 08/01/2013] [Accepted: 08/02/2013] [Indexed: 01/20/2023]
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27
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Boyer N, Morrison KC, Kim J, Hergenrother PJ, Movassaghi M. Synthesis and Anticancer Activity of Epipolythiodiketopiperazine Alkaloids. Chem Sci 2013; 4:1646-1657. [PMID: 23914293 PMCID: PMC3728915 DOI: 10.1039/c3sc50174d] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The epipolythiodiketopiperazine (ETP) alkaloids are a highly complex class of natural products with potent anticancer activity. Herein, we report the application of a flexible and scalable synthesis, allowing the construction of dozens of ETP derivatives. The evaluation of these compounds against cancer cell lines in culture allows for the first expansive structure-activity relationship (SAR) to be defined for monomeric and dimeric ETP-containing natural products and their synthetic cognates. Many ETP derivatives demonstrate potent anticancer activity across a broad range of cancer cell lines, and kill cancer cellsviainduction of apoptosis. Several traits thatbode well for the translational potential of the ETP class of natural products includeconcise and efficient synthetic access, potent induction of apoptotic cell death, activity against a wide range of cancer types, and a broad tolerance for modifications at multiple sitesthat should facilitate small-molecule drug development, mechanistic studies, and evaluation in vivo.
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Affiliation(s)
- Nicolas Boyer
- Massachusetts Institute of Technology, Department of Chemistry, Cambridge, Massachusetts 02139, USA
| | - Karen C. Morrison
- University of Illinois at Urbana-Champaign, Department of Chemistry, Urbana, Illinois 61801, USA
| | - Justin Kim
- Massachusetts Institute of Technology, Department of Chemistry, Cambridge, Massachusetts 02139, USA
| | - Paul J. Hergenrother
- University of Illinois at Urbana-Champaign, Department of Chemistry, Urbana, Illinois 61801, USA
| | - Mohammad Movassaghi
- Massachusetts Institute of Technology, Department of Chemistry, Cambridge, Massachusetts 02139, USA
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28
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Cherblanc FL, Davidson RWM, Di Fruscia P, Srimongkolpithak N, Fuchter MJ. Perspectives on natural product epigenetic modulators in chemical biology and medicine. Nat Prod Rep 2013; 30:605-24. [DOI: 10.1039/c3np20097c] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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29
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Abstract
The first total synthesis of (+)-gliocladin B is described. Our concise and enantioselective synthesis takes advantage of a new regioselective Friedel-Crafts-based strategy to provide an efficient multigram-scale access to the C3-(3'-indolyl)hexahydropyrroloindole substructure, a molecular foundation present in a significant subset of epipolythiodiketopiperazine natural alkaloids. Our first-generation solution to (+)-gliocladin B involved the stereoselective formation of (+)-12-deoxybionectin A, a plausible biosynthetic precursor. Our synthesis clarified the C15 stereochemistry of (+)-gliocladin B and allowed its full structure confirmation. Further studies of a versatile dihydroxylated diketopiperazine provided a concise and efficient synthesis of (+)-gliocladin B as well as access to (+)-gliocladin C.
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Affiliation(s)
| | - Mohammad Movassaghi
- Massachusetts Institute of Technology, Department of Chemistry, 77 Massachusetts Avenue 18-292, Cambridge, MA 02139-4307, USA
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30
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Guo C, Song J, Huang JZ, Chen PH, Luo SW, Gong LZ. Core-Structure-Oriented Asymmetric Organocatalytic Substitution of 3-Hydroxyoxindoles: Application in the Enantioselective Total Synthesis of (+)-Folicanthine. Angew Chem Int Ed Engl 2011; 51:1046-50. [DOI: 10.1002/anie.201107079] [Citation(s) in RCA: 221] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2011] [Indexed: 11/12/2022]
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31
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Guo C, Song J, Huang JZ, Chen PH, Luo SW, Gong LZ. Core-Structure-Oriented Asymmetric Organocatalytic Substitution of 3-Hydroxyoxindoles: Application in the Enantioselective Total Synthesis of (+)-Folicanthine. Angew Chem Int Ed Engl 2011. [DOI: 10.1002/ange.201107079] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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32
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Duke SO, Dayan FE. Modes of action of microbially-produced phytotoxins. Toxins (Basel) 2011; 3:1038-1064. [PMID: 22069756 PMCID: PMC3202864 DOI: 10.3390/toxins3081038] [Citation(s) in RCA: 83] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2011] [Revised: 08/15/2011] [Accepted: 08/17/2011] [Indexed: 01/17/2023] Open
Abstract
Some of the most potent phytotoxins are synthesized by microbes. A few of these share molecular target sites with some synthetic herbicides, but many microbial toxins have unique target sites with potential for exploitation by the herbicide industry. Compounds from both non-pathogenic and pathogenic microbes are discussed. Microbial phytotoxins with modes of action the same as those of commercial herbicides and those with novel modes of action of action are covered. Examples of the compounds discussed are tentoxin, AAL-toxin, auscaulitoxin aglycone, hydantocidin, thaxtomin, and tabtoxin.
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Affiliation(s)
- Stephen O. Duke
- United States Department of Agriculture, Agricultural Research Service, Natural Products Utilization Research Unit, P. O. Box 8048, MS 38677, USA;
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33
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Scharf DH, Remme N, Habel A, Chankhamjon P, Scherlach K, Heinekamp T, Hortschansky P, Brakhage AA, Hertweck C. A dedicated glutathione S-transferase mediates carbon-sulfur bond formation in gliotoxin biosynthesis. J Am Chem Soc 2011; 133:12322-5. [PMID: 21749092 DOI: 10.1021/ja201311d] [Citation(s) in RCA: 99] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Gliotoxin is a virulence factor of the human pathogen Aspergillus fumigatus , the leading cause of invasive aspergillosis. Its toxicity is mediated by the unusual transannular disulfide bridge of the epidithiodiketopiperazine (ETP) scaffold. Here we disclose the critical role of a specialized glutathione S-transferase (GST), GliG, in enzymatic sulfurization. Furthermore, we show that bishydroxylation of the diketopiperazine by the oxygenase GliC is a prerequisite for glutathione adduct formation. This is the first report of the involvement of a GST in enzymatic C-S bond formation in microbial secondary metabolism.
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Affiliation(s)
- Daniel H Scharf
- Leibniz Institute for Natural Product Research and Infection Biology, Beutenbergstr. 11a, 07745 Jena, Germany
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34
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DeLorbe JE, Jabri SY, Mennen SM, Overman LE, Zhang FL. Enantioselective total synthesis of (+)-gliocladine C: convergent construction of cyclotryptamine-fused polyoxopiperazines and a general approach for preparing epidithiodioxopiperazines from trioxopiperazine precursors. J Am Chem Soc 2011; 133:6549-52. [PMID: 21473649 DOI: 10.1021/ja201789v] [Citation(s) in RCA: 145] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
A concise second-generation total synthesis of the fungal-derived alkaloid (+)-gliocladin C (11) in 10 steps and 11% overall yield from isatin is reported. In addition, the epipolythiodioxopiperazine (ETP) natural product (+)-gliocladine C (6) has been prepared in six steps and 29% yield from the di-(tert-butoxycarbonyl) precursor of 11. The total synthesis of 6 constitutes the first total synthesis of an ETP natural product containing a hydroxyl substituent adjacent to a quaternary carbon stereocenter in the pyrrolidine ring.
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Affiliation(s)
- John E DeLorbe
- Department of Chemistry, 1102 Natural Sciences II, University of California, Irvine, California 92697-2025, USA
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35
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Iwasa E, Hamashima Y, Sodeoka M. Epipolythiodiketopiperazine Alkaloids: Total Syntheses and Biological Activities. Isr J Chem 2011. [DOI: 10.1002/ijch.201100012] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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36
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Scharf DH, Remme N, Heinekamp T, Hortschansky P, Brakhage AA, Hertweck C. Transannular disulfide formation in gliotoxin biosynthesis and its role in self-resistance of the human pathogen Aspergillus fumigatus. J Am Chem Soc 2010; 132:10136-41. [PMID: 20593880 DOI: 10.1021/ja103262m] [Citation(s) in RCA: 116] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
Gliotoxin (1), the infamous representative of the group of epipolythiodioxopiperazines (ETPs), is a virulence factor of the human pathogenic fungus Aspergillus fumigatus. The unique redox-sensitive transannular disulfide bridge is critical for deleterious effects caused by redox cycling and protein conjugation in the host. Through a combination of genetic, biochemical, and chemical analyses, we found that 1 results from GliT-mediated oxidation of the corresponding dithiol. In vitro studies using purified GliT demonstrate that the FAD-dependent, homodimeric enzyme utilizes molecular oxygen as terminal electron acceptor with concomitant formation of H(2)O(2). In analogy to the thiol-disulfide oxidoreductase superfamily, a model for dithiol-disulfide exchange involving the conserved CxxC motif is proposed. Notably, while all studied disulfide oxidases invariably form intra- or interchenar disulfide bonds in peptides, GliT is the first studied enzyme producing an epidithio bond. Furthermore, through sensitivity assays using wild type, Delta gliT mutant, and complemented strain, we found that GliT confers resistance to the producing organism. A phylogenetic study revealed that GliT falls into a clade of yet fully uncharacterized fungal gene products deduced from putative ETP biosynthesis gene loci. GliT thus not only represents the prototype of ETP-forming enzymes in eukaryotes but also delineates a novel mechanism for self-resistance.
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Affiliation(s)
- Daniel H Scharf
- Leibniz Institute for Natural Product Research and Infection Biology, Beutenbergstrasse 11a, 07745 Jena, Germany
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37
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Cook KM, Hilton ST, Mecinović J, Motherwell WB, Figg WD, Schofield CJ. Epidithiodiketopiperazines block the interaction between hypoxia-inducible factor-1alpha (HIF-1alpha) and p300 by a zinc ejection mechanism. J Biol Chem 2009; 284:26831-8. [PMID: 19589782 PMCID: PMC2785371 DOI: 10.1074/jbc.m109.009498] [Citation(s) in RCA: 130] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2009] [Revised: 07/01/2009] [Indexed: 11/06/2022] Open
Abstract
The hypoxic response in humans is regulated by the hypoxia-inducible transcription factor system; inhibition of hypoxia-inducible factor (HIF) activity has potential for the treatment of cancer. Chetomin, a member of the epidithiodiketopiperazine (ETP) family of natural products, inhibits the interaction between HIF-alpha and the transcriptional coactivator p300. Structure-activity studies employing both natural and synthetic ETP derivatives reveal that only the structurally unique ETP core is required and sufficient to block the interaction of HIF-1alpha and p300. In support of both cell-based and animal work showing that the cytotoxic effect of ETPs is reduced by the addition of Zn(2+) through an unknown mechanism, our mechanistic studies reveal that ETPs react with p300, causing zinc ion ejection. Cell studies with both natural and synthetic ETPs demonstrated a decrease in vascular endothelial growth factor and antiproliferative effects that were abrogated by zinc supplementation. The results have implications for the design of selective ETPs and for the interaction of ETPs with other zinc ion-binding protein targets involved in gene expression.
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MESH Headings
- Binding Sites
- Cell Line, Tumor
- Cell Proliferation/drug effects
- Cell Survival/drug effects
- Disulfides/chemistry
- Disulfides/pharmacology
- Dose-Response Relationship, Drug
- HCT116 Cells
- Humans
- Hypoxia-Inducible Factor 1, alpha Subunit/chemistry
- Hypoxia-Inducible Factor 1, alpha Subunit/genetics
- Hypoxia-Inducible Factor 1, alpha Subunit/metabolism
- Indole Alkaloids/chemistry
- Indole Alkaloids/pharmacology
- Models, Chemical
- Models, Molecular
- Molecular Sequence Data
- Molecular Structure
- Protein Binding/drug effects
- Protein Structure, Tertiary
- Spectrometry, Mass, Electrospray Ionization
- Structure-Activity Relationship
- Vascular Endothelial Growth Factor A/metabolism
- Zinc/chemistry
- Zinc/pharmacology
- p300-CBP Transcription Factors/chemistry
- p300-CBP Transcription Factors/genetics
- p300-CBP Transcription Factors/metabolism
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Affiliation(s)
- Kristina M. Cook
- From NCI, National Institutes of Health, Bethesda, Maryland 20814
- the Chemistry Research Laboratory, Department of Chemistry, and the Oxford Centre for Integrative Systems Biology, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - Stephen T. Hilton
- the Department of Pharmaceutical and Biological Chemistry, School of Pharmacy, University of London, London WC1N 1AX, United Kingdom, and
| | - Jasmin Mecinović
- the Chemistry Research Laboratory, Department of Chemistry, and the Oxford Centre for Integrative Systems Biology, University of Oxford, Oxford OX1 3TA, United Kingdom
| | - William B. Motherwell
- the Department of Chemistry, University College London, London WC1H 0AJ, United Kingdom
| | - William D. Figg
- From NCI, National Institutes of Health, Bethesda, Maryland 20814
| | - Christopher J. Schofield
- the Chemistry Research Laboratory, Department of Chemistry, and the Oxford Centre for Integrative Systems Biology, University of Oxford, Oxford OX1 3TA, United Kingdom
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38
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Aliev AE, Hilton ST, Motherwell WB, Selwood DL. A concise approach to the epidithiodiketopiperazine (ETP) core. Tetrahedron Lett 2006. [DOI: 10.1016/j.tetlet.2006.01.156] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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39
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Duncan EJ, Thompson MP, Phua SH. Zinc protection of HepG2 cells from sporidesmin toxicity does not require de novo gene transcription. Toxicol Lett 2005; 159:164-72. [PMID: 16005584 DOI: 10.1016/j.toxlet.2005.05.005] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2005] [Revised: 05/19/2005] [Accepted: 05/19/2005] [Indexed: 11/25/2022]
Abstract
Sporidesmin is an epidithiodioxopiperazine mycotoxin secreted by the saprophytic fungus Pithomyces chartarum. Ingestion of sporidesmin by ruminants grazing on the saprophyte infested pasture causes severe liver and bile duct damage leading to secondary photosensitisation. Zinc supplementation is used as an effective prophylaxis against sporidesmin toxicity in ruminants, however, the mechanism by which zinc protects is unknown. This study used the human hepatoma cell line, HepG2, as a model to examine the mechanism of zinc protection against sporidesmin toxicity. Treatment of cells with various concentrations of sporidesmin (0-10 microg/ml) resulted in a sigmoidal dose response curve with an LC50 of 5 microg/ml. Cells were protected from sporidesmin toxicity by pre-treatment for 2h or 16 h with zinc sulphate in a concentration dependent manner, with significant protection at 50 microM zinc and maximal protection at 200 microM zinc. To determine whether zinc protection required de novo gene transcription, cells were treated with the transcriptional inhibitor actinomycin D for one hour prior to and throughout the zinc pre-treatment. The presence of actinomycin D did not significantly reduce the zinc protection against sporidesmin cytotoxicity (80% protection without actinomycin D versus 71% protection with actinomycin D). Therefore, de novo gene transcription does not play a major role in the mechanism of zinc protection against sporidesmin toxicity in HepG2 cells.
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Affiliation(s)
- Elizabeth J Duncan
- AgResearch Molecular Biology Unit, Department of Biochemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand
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40
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Gardiner DM, Howlett BJ. Bioinformatic and expression analysis of the putative gliotoxin biosynthetic gene cluster ofAspergillus fumigatus. FEMS Microbiol Lett 2005; 248:241-8. [PMID: 15979823 DOI: 10.1016/j.femsle.2005.05.046] [Citation(s) in RCA: 196] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2005] [Revised: 05/14/2005] [Accepted: 05/25/2005] [Indexed: 11/29/2022] Open
Abstract
Gliotoxin is a secondary metabolite produced by several fungi including the opportunistic animal pathogen Aspergillus fumigatus. It is a member of the epipolythiodioxopiperazine (ETP) class of toxins characterised by a disulphide bridged cyclic dipeptide. A putative cluster of 12 genes involved in gliotoxin biosynthesis has been identified in A. fumigatus by a comparative genomics approach based on homology to genes from the sirodesmin (another ETP) biosynthetic gene cluster of Leptosphaeria maculans. The physical limits of the cluster in A. fumigatus have been defined by bioinformatics and by identifying the genes that are co-regulated and whose timing of expression correlates with the production of gliotoxin in culture.
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41
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Morgavi DP, Boudra H, Jouany JP, Michalet-Doreau B. Effect and stability of gliotoxin, an Aspergillus fumigatus toxin, on in vitro rumen fermentation. ACTA ACUST UNITED AC 2005; 21:871-8. [PMID: 15666981 DOI: 10.1080/02652030400002188] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
Aspergillus fumigatus is a toxicogenic fungus usually found in contaminated animal feeds, especially in conserved forages where it can produce several mycotoxins. Gliotoxin, one of the most important toxic metabolites produced by this fungus, has antibacterial, immunosuppressive and apoptotic effects. Ruminants due to the high proportion of forages they receive in the ration would be particularly exposed to gliotoxin. The objective of this work was (1) to assess the effect of gliotoxin on in vitro rumen fermentation and (2) to determine the effect of fermentation on gliotoxin stability. Gliotoxin did not affect rumen fermentation at concentrations found in naturally contaminated feeds. No effects were observed up to a concentration of 20 microg toxin ml(-1) and an extremely high toxin concentration (80 microg ml(-1)) was necessary to affect dry matter degradation, gas and total volatile fatty acids production by 24, 37 and 18%, respectively (p < 0.01). In addition, the toxin was unstable in the rumen environment with 90% disappearance at 6 h of incubation (p < 0.05). In contrast, extracts of A. fumigatus cultures containing gliotoxin at concentrations several times lower than that used for experiments with pure toxin had a negative effect on fermentations indicating the toxicity and possible synergism of other metabolites produced by this fungus. Extracts containing 8.8 microg gliotoxin ml(-1) decreased dry matter degradation, gas and volatile fatty acids production by 28, 46 and 35%, respectively (p < 0.01). Identification of these toxic metabolites and assessment of the rate of passage of gliotoxin to the lower intestinal tract is necessary to evaluate the potential risk of these toxins to ruminants.
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Affiliation(s)
- D P Morgavi
- French Institute for Agricultural Research (INRA), Clermont-Fd-Theix Research Centre, Herbivore Research Unit, F-63122 Saint Genès-Champanelle, France.
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42
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Hilton ST, Motherwell WB, Potier P, Pradet C, Selwood DL. Observations on the reactivity of thiyl radicals derived from 3,6-epidithiodiketopiperazine-2,5-diones and related congeners. Bioorg Med Chem Lett 2005; 15:2239-42. [PMID: 15837301 DOI: 10.1016/j.bmcl.2005.03.022] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2004] [Revised: 01/22/2005] [Accepted: 03/07/2005] [Indexed: 10/25/2022]
Abstract
A range of thiyl radicals derived from the reduced form of epidithiodiketopiperazines (ETPs) act as polarity reversal catalysts for the hydrosilylation of an enol lactone but not for H-atom abstraction from a model ribose ester.
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Affiliation(s)
- S T Hilton
- Chemistry Department, University College London, Christopher Ingold Laboratories, 20 Gordon Street, London WC1H OAJ, UK
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43
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Chai CLL, Elix JA, Huleatt PB, Waring P. Scabrosin esters and derivatives: chemical derivatization studies and biological evaluation. Bioorg Med Chem 2005; 12:5991-5. [PMID: 15498675 DOI: 10.1016/j.bmc.2004.08.015] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2004] [Revised: 08/09/2004] [Accepted: 08/12/2004] [Indexed: 10/26/2022]
Abstract
Several derivatives of the natural scabrosin esters were synthesized in order to elucidate the structural features present, which are responsible for the biological activities. The studies demonstrate that full anti-proliferative activities of the scabrosin esters, both the carboskeleton core as well as the ability to form the dithiol and/or the disulfide linkage of the epidithiopiperazine-2,5-dione are required. The presence of the epoxide rings on the scabrosin esters do not contribute to the observed biological activities.
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Affiliation(s)
- Christina L L Chai
- Centre for the Study of Bioactive Molecules, Department of Chemistry, Australian National University, Canberra ACT 0200, Australia.
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44
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Gardiner DM, Cozijnsen AJ, Wilson LM, Pedras MSC, Howlett BJ. The sirodesmin biosynthetic gene cluster of the plant pathogenic fungus Leptosphaeria maculans. Mol Microbiol 2005; 53:1307-18. [PMID: 15387811 DOI: 10.1111/j.1365-2958.2004.04215.x] [Citation(s) in RCA: 161] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Sirodesmin PL is a phytotoxin produced by the fungus Leptosphaeria maculans, which causes blackleg disease of canola (Brassica napus). This phytotoxin belongs to the epipolythiodioxopiperazine (ETP) class of toxins produced by fungi including mammalian and plant pathogens. We report the cloning of a cluster of genes with predicted roles in the biosynthesis of sirodesmin PL and show via gene disruption that one of these genes (encoding a two-module non-ribosomal peptide synthetase) is essential for sirodesmin PL biosynthesis. Of the nine genes in the cluster tested, all are co-regulated with the production of sirodesmin PL in culture. A similar cluster is present in the genome of the opportunistic human pathogen Aspergillus fumigatus and is most likely responsible for the production of gliotoxin, which is also an ETP. Homologues of the genes in the cluster were also identified in expressed sequence tags of the ETP producing fungus Chaetomium globosum. Two other fungi with publicly available genome sequences, Magnaporthe grisea and Fusarium graminearum, had similar gene clusters. A comparative analysis of all four clusters is presented. This is the first report of the genes responsible for the biosynthesis of an ETP.
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Affiliation(s)
- Donald M Gardiner
- School of Botany, The University of Melbourne, Victoria, Australia 3010.
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45
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Bernardo PH, Brasch N, Chai CLL, Waring P. A novel redox mechanism for the glutathione-dependent reversible uptake of a fungal toxin in cells. J Biol Chem 2003; 278:46549-55. [PMID: 12947114 DOI: 10.1074/jbc.m304825200] [Citation(s) in RCA: 73] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The fungal metabolite gliotoxin is characterized by an internal disulfide bridge and can exist in either disulfide or dithiol forms. Gliotoxin and other members of the epipolythiodioxopiperazine class of toxins have immunosuppressive properties and have been implicated in human and animal mycotoxicoses. The bridged disulfide moiety is thought to be generally essential for biological activity. Here we show that only the natural (oxidized) form of gliotoxin is actively concentrated in a cell line in a glutathione-dependent manner. Intracellular levels of the toxin can be up to 1500-fold greater than the applied concentration, and toxin in the cells exists almost exclusively in the reduced form. A simple model of toxin entry followed by reduction to the cell-impermeant dithiol explains active uptake, cell density dependence of EC50 values and predicts a value for the maximum concentration of toxin at limiting cell density in agreement with the experiment. Oxidation of the intracellular toxin results in rapid efflux from the cell that also occurs when glutathione levels fall following induction of apoptotic cell death by the toxin. This mechanism allows for minimal production of the toxin while enabling maximal intracellular concentration and thus maximal efficacy of killing in a competitor organism initially present at low cell density. The toxin effluxes from the apoptotic cell exclusively in the oxidized form and can further enter and kill neighboring cells, thus acting in a pseudocatalytic way.
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Affiliation(s)
- Paul H Bernardo
- Centre for the Study of Bioactive Molecules, Department of Chemistry, The Faculties, Australian National University, Canberra 0200, Australia
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46
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Moody CJ, Slawin AMZ, Willows D. Dirhodium(II) tetraacetate catalysed reactions of diazo thioamides: isolation and cycloaddition of anhydro-4-hydroxy-1,3-thiazolium hydroxides (thioisomünchnones), an approach to analogues of dehydrogliotoxin. Org Biomol Chem 2003; 1:2716-22. [PMID: 12948196 DOI: 10.1039/b305698h] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Dirhodium(II) tetraacetate catalysed reaction of the indoline diazo thioamide 8 gives the thioisomünchnone 9, a stable characterisable solid. This masked thiocarbonyl ylide undergoes 1,3-dipolar cycloaddition with N-methylmaleimide and maleic anhydride to give the exo-cycloadducts 10 and 11, characterised by X-ray crystallography. The thioisomünchnone 18, derived from diazo thioamide 17, is an extremely stable crystalline mesoionic system which can be characterised by X-ray crystallography but fails to undergo intramolecular cycloaddition. The related thioisomünchnone 19 can be generated by reaction of indoline-2-thione 7 with bromoacetyl chloride in the presence of triethylamine, and undergoes cycloaddition to give adducts 20 and 21.
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Affiliation(s)
- Christopher J Moody
- School of Chemistry, University of Exeter, Stocker Road, Exeter, UK EX4 4QD.
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