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Carvalho LADC, Noma IHY, Uehara AH, Siena ÁDD, Osaki LH, Mori MP, Pinto NCDS, Freitas VM, Junior WAS, Smalley KSM, Maria-Engler SS. Modeling Melanoma Heterogeneity In Vitro: Redox, Resistance and Pigmentation Profiles. Antioxidants (Basel) 2024; 13:555. [PMID: 38790661 PMCID: PMC11118096 DOI: 10.3390/antiox13050555] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Revised: 04/21/2024] [Accepted: 04/25/2024] [Indexed: 05/26/2024] Open
Abstract
Microenvironment and transcriptional plasticity generate subpopulations within the tumor, and the use of BRAF inhibitors (BRAFis) contributes to the rise and selection of resistant clones. We stochastically isolated subpopulations (C1, C2, and C3) from naïve melanoma and found that the clones demonstrated distinct morphology, phenotypic, and functional profiles: C1 was less proliferative, more migratory and invasive, less sensitive to BRAFis, less dependent on OXPHOS, more sensitive to oxidative stress, and less pigmented; C2 was more proliferative, less migratory and invasive, more sensitive to BRAFis, less sensitive to oxidative stress, and more pigmented; and C3 was less proliferative, more migratory and invasive, less sensitive to BRAFis, more dependent on OXPHOS, more sensitive to oxidative stress, and more pigmented. Hydrogen peroxide plays a central role in oxidative stress and cell signaling, and PRDXs are one of its main consumers. The intrinsically resistant C1 and C3 clones had lower MITF, PGC-1α, and PRDX1 expression, while C1 had higher AXL and decreased pigmentation markers, linking PRDX1 to clonal heterogeneity and resistance. PRDX2 is depleted in acquired BRAFi-resistant cells and acts as a redox sensor. Our results illustrate that decreased pigmentation markers are related to therapy resistance and decreased antioxidant defense.
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Affiliation(s)
- Larissa Anastacio da Costa Carvalho
- Department of Tumor Biology, Moffitt Cancer Center, Tampa, FL 33612, USA; (L.A.d.C.C.); (K.S.M.S.)
- Department of Clinical and Toxicological Analysis, School of Pharmaceutical Sciences, University of São Paulo, São Paulo 05508-000, SP, Brazil; (I.H.Y.N.); (A.H.U.)
| | - Isabella Harumi Yonehara Noma
- Department of Clinical and Toxicological Analysis, School of Pharmaceutical Sciences, University of São Paulo, São Paulo 05508-000, SP, Brazil; (I.H.Y.N.); (A.H.U.)
| | - Adriana Hiromi Uehara
- Department of Clinical and Toxicological Analysis, School of Pharmaceutical Sciences, University of São Paulo, São Paulo 05508-000, SP, Brazil; (I.H.Y.N.); (A.H.U.)
| | - Ádamo Davi Diógenes Siena
- Department of Genetics, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto 14049-900, SP, Brazil; (Á.D.D.S.); (W.A.S.J.)
| | - Luciana Harumi Osaki
- Department of Cell Biology and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508-000, SP, Brazil; (L.H.O.); (V.M.F.)
| | - Mateus Prates Mori
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo 05508-000, SP, Brazil; (M.P.M.); (N.C.d.S.P.)
| | - Nadja Cristhina de Souza Pinto
- Department of Biochemistry, Institute of Chemistry, University of São Paulo, São Paulo 05508-000, SP, Brazil; (M.P.M.); (N.C.d.S.P.)
| | - Vanessa Morais Freitas
- Department of Cell Biology and Developmental Biology, Institute of Biomedical Sciences, University of São Paulo, São Paulo 05508-000, SP, Brazil; (L.H.O.); (V.M.F.)
| | - Wilson Araújo Silva Junior
- Department of Genetics, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto 14049-900, SP, Brazil; (Á.D.D.S.); (W.A.S.J.)
| | - Keiran S. M. Smalley
- Department of Tumor Biology, Moffitt Cancer Center, Tampa, FL 33612, USA; (L.A.d.C.C.); (K.S.M.S.)
| | - Silvya Stuchi Maria-Engler
- Department of Clinical and Toxicological Analysis, School of Pharmaceutical Sciences, University of São Paulo, São Paulo 05508-000, SP, Brazil; (I.H.Y.N.); (A.H.U.)
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Exposure of Aspergillus fumigatus to Klebsiella pneumoniae Culture Filtrate Inhibits Growth and Stimulates Gliotoxin Production. J Fungi (Basel) 2023; 9:jof9020222. [PMID: 36836336 PMCID: PMC9961802 DOI: 10.3390/jof9020222] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 02/01/2023] [Accepted: 02/03/2023] [Indexed: 02/10/2023] Open
Abstract
Aspergillus fumigatus is an opportunistic fungal pathogen capable of inducing chronic and acute infection in susceptible patients. A. fumigatus interacts with numerous bacteria that compose the microbiota of the lung, including Pseudomonas aeruginosa and Klebsiella pneumoniae, both of which are common isolates from cystic fibrosis sputum. Exposure of A. fumigatus to K. pneumoniae culture filtrate reduced fungal growth and increased gliotoxin production. Qualitative proteomic analysis of the K. pneumoniae culture filtrate identified proteins associated with metal sequestering, enzymatic degradation and redox activity, which may impact fungal growth and development. Quantitative proteomic analysis of A. fumigatus following exposure to K. pneumoniae culture filtrate (25% v/v) for 24 h revealed a reduced abundance of 1,3-beta-glucanosyltransferase (-3.97 fold), methyl sterol monooxygenase erg25B (-2.9 fold) and calcium/calmodulin-dependent protein kinase (-4.2 fold) involved in fungal development, and increased abundance of glutathione S-transferase GliG (+6.17 fold), non-ribosomal peptide synthase GliP (+3.67 fold), O-methyltransferase GliM (+3.5 fold), gamma-glutamyl acyltransferase GliK (+2.89 fold) and thioredoxin reductase GliT (+2.33 fold) involved in gliotoxin production. These results reveal that exposure of A. fumigatus to K. pneumoniae in vivo could exacerbate infection and negatively impact patient prognosis.
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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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Ye W, Li S, Liu S, Kong Y, Zhang W, Liu S, Liu T, Zhang W. Characterization of novel gliotoxin biosynthesis-related genes from deep-sea-derived fungus Geosmithia pallida FS140. Biochimie 2021; 191:1-10. [PMID: 34364944 DOI: 10.1016/j.biochi.2021.08.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2021] [Revised: 07/24/2021] [Accepted: 08/03/2021] [Indexed: 11/15/2022]
Abstract
Gliotoxins are epipolythiodioxopiperazine toxins produced by the filamentous fungi, which show great potential in the treatment of liver and lung cancer because of its cytotoxicity. In this study, three novel genes related to gliotoxin biosynthesis, gliT, gliM and gliK encoding thioredoxin reductase, O-methyltransferase and gamma-glutamyl cyclotransferase, respectively, from the deep-sea-derived fungus Geosmithia pallida were cloned from G. pallida and expressed in Escherichia coli. The recombinant GliT, GliM and GliK proteins were expressed and purified by Ni affinity column, which was demonstrated by SDS-PAGE and Western blot analysis. The inclusion bodies of GliT were renatured and the corresponding enzymatic properties of the two enzymes were further investigated. Using DTNB as a substrate, GliT showed the highest enzymatic activity of 11041 mU/L at pH 7.0, and the optimal reaction temperature was 40 °C. Using EGCG as a substrate, GliM showed the highest enzymatic activity of 239.19 mU/mg at pH 7.0, the optimum temperature was 35 °C. GliK from G. pallida was firstly reported to show bi-function of glutymal cyclotransferase and acetyltransfearse actvity with highest enzymatic activity of 615.5 U/mg in this study. The results suggested the important enzymatic function of GliT, GliM and GliK in the gliotoxin biosynthesis in G. pallida, which would lay a foundation for the mechanism elucidation of the gliotoxin biosynthesis in G. pallida and the exploitation of novel gliotoxin derivaties.
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Affiliation(s)
- Wei Ye
- Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, China
| | - Saini Li
- Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, China
| | - Shuai Liu
- Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, China
| | - Yali Kong
- Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, China
| | - Weiyang Zhang
- Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, China
| | - Shan Liu
- Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, China
| | - Taomei Liu
- Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, China
| | - Weimin Zhang
- Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, China.
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Turning Inside Out: Filamentous Fungal Secretion and Its Applications in Biotechnology, Agriculture, and the Clinic. J Fungi (Basel) 2021; 7:jof7070535. [PMID: 34356914 PMCID: PMC8307877 DOI: 10.3390/jof7070535] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 06/14/2021] [Accepted: 06/25/2021] [Indexed: 12/15/2022] Open
Abstract
Filamentous fungi are found in virtually every marine and terrestrial habitat. Vital to this success is their ability to secrete a diverse range of molecules, including hydrolytic enzymes, organic acids, and small molecular weight natural products. Industrial biotechnologists have successfully harnessed and re-engineered the secretory capacity of dozens of filamentous fungal species to make a diverse portfolio of useful molecules. The study of fungal secretion outside fermenters, e.g., during host infection or in mixed microbial communities, has also led to the development of novel and emerging technological breakthroughs, ranging from ultra-sensitive biosensors of fungal disease to the efficient bioremediation of polluted environments. In this review, we consider filamentous fungal secretion across multiple disciplinary boundaries (e.g., white, green, and red biotechnology) and product classes (protein, organic acid, and secondary metabolite). We summarize the mechanistic understanding for how various molecules are secreted and present numerous applications for extracellular products. Additionally, we discuss how the control of secretory pathways and the polar growth of filamentous hyphae can be utilized in diverse settings, including industrial biotechnology, agriculture, and the clinic.
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Thesmar P, Coomar S, Prescimone A, Häussinger D, Gillingham D, Baudoin O. Divergent Synthesis of Bioactive Dithiodiketopiperazine Natural Products Based on a Double C(sp 3 )-H Activation Strategy. Chemistry 2020; 26:15298-15312. [PMID: 32852800 DOI: 10.1002/chem.202003683] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2020] [Revised: 08/26/2020] [Indexed: 12/28/2022]
Abstract
This article provides a detailed report of our efforts to synthesize the dithiodiketopiperazine (DTP) natural products (-)-epicoccin G and (-)-rostratin A using a double C(sp3 )-H activation strategy. The strategy's viability was first established on a model system lacking the C8/C8' alcohols. Then, an efficient stereoselective route including an organocatalytic epoxidation was secured to access a key bis-triflate substrate. This bis-triflate served as the functional handles for the key transformation of the synthesis: a double C(sp3 )-H activation. The successful double activation opened access to a common intermediate for both natural products in high overall yield and on a multigram scale. After several unsuccessful attempts, this intermediate was efficiently converted to (-)-epicoccin G and to the more challenging (-)-rostratin A via suitable oxidation/reduction and protecting group sequences, and via a final sulfuration that occurred in good yield and high diastereoselectivity. These efforts culminated in the synthesis of (-)-epicoccin G and (-)-rostratin A in high overall yields (19.6 % over 14 steps and 12.7 % over 17 steps, respectively), with the latter being obtained on a 500 mg scale. Toxicity assessments of these natural products and several analogues (including the newly synthesized epicoccin K) in the leukemia cell line K562 confirmed the importance of the disulfide bridge for activity and identified dianhydrorostratin A as a 20x more potent analogue.
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Affiliation(s)
- Pierre Thesmar
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056, Basel, Switzerland
| | - Seemon Coomar
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056, Basel, Switzerland
| | - Alessandro Prescimone
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056, Basel, Switzerland
| | - Daniel Häussinger
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056, Basel, Switzerland
| | - Dennis Gillingham
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056, Basel, Switzerland
| | - Olivier Baudoin
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056, Basel, Switzerland
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Zhang J, Duan D, Song ZL, Liu T, Hou Y, Fang J. Small molecules regulating reactive oxygen species homeostasis for cancer therapy. Med Res Rev 2020; 41:342-394. [PMID: 32981100 DOI: 10.1002/med.21734] [Citation(s) in RCA: 87] [Impact Index Per Article: 21.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2020] [Revised: 07/27/2020] [Accepted: 08/22/2020] [Indexed: 12/13/2022]
Abstract
Elevated intracellular reactive oxygen species (ROS) and antioxidant defense systems have been recognized as one of the hallmarks of cancer cells. Compared with normal cells, cancer cells exhibit increased ROS to maintain their malignant phenotypes and are more dependent on the "redox adaptation" mechanism. Thus, there are two apparently contradictory but virtually complementary therapeutic strategies for the regulation of ROS to prevent or treat cancer. The first strategy, that is, chemoprevention, is to prevent or reduce intracellular ROS either by suppressing ROS production pathways or by employing antioxidants to enhance ROS clearance, which protects normal cells from malignant transformation and inhibits the early stage of tumorigenesis. The second strategy is the ROS-mediated anticancer therapy, which stimulates intracellular ROS to a toxicity threshold to activate ROS-induced cell death pathways. Therefore, targeting the regulation of intracellular ROS-related pathways by small-molecule candidates is considered to be a promising treatment for tumors. We herein first briefly introduce the source and regulation of ROS, and then focus on small molecules that regulate ROS-related pathways and show efficacy in cancer therapy from the perspective of pharmacophores. Finally, we discuss several challenges in developing cancer therapeutic agents based on ROS regulation and propose the direction of future development.
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Affiliation(s)
- Junmin Zhang
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, and School of Pharmacy, Lanzhou University, Lanzhou, China
| | - Dongzhu Duan
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, and School of Pharmacy, Lanzhou University, Lanzhou, China.,Shaanxi Key Laboratory of Phytochemistry, Baoji University of Arts and Sciences, Baoji, China
| | - Zi-Long Song
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, and School of Pharmacy, Lanzhou University, Lanzhou, China
| | - Tianyu Liu
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, and School of Pharmacy, Lanzhou University, Lanzhou, China
| | - Yanan Hou
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, and School of Pharmacy, Lanzhou University, Lanzhou, China
| | - Jianguo Fang
- State Key Laboratory of Applied Organic Chemistry, College of Chemistry and Chemical Engineering, and School of Pharmacy, Lanzhou University, Lanzhou, China
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Gayathri L, Akbarsha MA, Ruckmani K. In vitro study on aspects of molecular mechanisms underlying invasive aspergillosis caused by gliotoxin and fumagillin, alone and in combination. Sci Rep 2020; 10:14473. [PMID: 32879392 PMCID: PMC7467938 DOI: 10.1038/s41598-020-71367-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2020] [Accepted: 08/06/2020] [Indexed: 12/19/2022] Open
Abstract
Gliotoxin (GT) and fumagillin (FUM) are mycotoxins most abundantly produced by Aspergillus fumigatus during the early stages of infection to cause invasive aspergillosis (IA). Therefore, we hypothesized that GT and FUM could be the possible source of virulence factors, which we put to test adopting in vitro monoculture and the novel integrated multiple organ co-culture (IdMOC) of A549 and L132 cell. We found that (i) GT is more cytotoxic to lung epithelial cells than FUM, and (ii) GT and FUM act synergistically to inflict pathology to the lung epithelial cell. Reactive oxygen species (ROS) is the master regulator of the cytotoxicity of GT, FUM and GT + FUM. ROS may be produced as a sequel to mitochondrial damage and, thus, mitochondria are both the source of ROS and the target to ROS. GT-, FUM- and GT + FUM-induced DNA damage is mediated either by ROS-dependent mechanism or directly by the fungal toxins. In addition, GT, FUM and GT + FUM may induce protein accumulation. Further, it is speculated that GT and FUM inflict epithelial damage by neutrophil-mediated inflammation. With respect to multiple organ cytotoxicity, GT was found to be cytotoxic at IC50 concentration in the following order: renal epithelial cells < type II epithelial cells < hepatocytes < normal lung epithelial cells. Taken together, GT and FUM alone and in combination contribute to exacerbate the damage of lung epithelial cells and, thus, are involved in the progression of IA.
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Affiliation(s)
- Loganathan Gayathri
- Department of Pharmaceutical Technology, University College of Engineering, Anna University-BIT Campus, Tiruchchirappalli, Tamil Nadu, 620024, India
- Centre for Excellence in Nanobio Translational Research (Autonomous), University College of Engineering, Anna University-BIT Campus, Tiruchchirappalli, Tamil Nadu, 620024, India
- Department of Biotechnology and Bioinformatics, Holy Cross College (Autonomous), Tiruchchirappalli, Tamil Nadu, 620002, India
| | - Mohammad A Akbarsha
- National College (Autonomous), Tiruchchirappalli, Tamil Nadu, 620001, India
- Mahatma Gandhi-Doerenkamp Centre for Alternatives, Bharathidasan University, Tiruchchirappalli, Tamil Nadu, 620 024, India
| | - Kandasamy Ruckmani
- Department of Pharmaceutical Technology, University College of Engineering, Anna University-BIT Campus, Tiruchchirappalli, Tamil Nadu, 620024, India.
- Centre for Excellence in Nanobio Translational Research (Autonomous), University College of Engineering, Anna University-BIT Campus, Tiruchchirappalli, Tamil Nadu, 620024, India.
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Stoszko M, Al-Hatmi AMS, Skriba A, Roling M, Ne E, Crespo R, Mueller YM, Najafzadeh MJ, Kang J, Ptackova R, LeMasters E, Biswas P, Bertoldi A, Kan TW, de Crignis E, Sulc M, Lebbink JH, Rokx C, Verbon A, van Ijcken W, Katsikis PD, Palstra RJ, Havlicek V, de Hoog S, Mahmoudi T. Gliotoxin, identified from a screen of fungal metabolites, disrupts 7SK snRNP, releases P-TEFb, and reverses HIV-1 latency. SCIENCE ADVANCES 2020; 6:eaba6617. [PMID: 32851167 PMCID: PMC7423394 DOI: 10.1126/sciadv.aba6617] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 07/01/2020] [Indexed: 05/16/2023]
Abstract
A leading pharmacological strategy toward HIV cure requires "shock" or activation of HIV gene expression in latently infected cells with latency reversal agents (LRAs) followed by their subsequent clearance. In a screen for novel LRAs, we used fungal secondary metabolites as a source of bioactive molecules. Using orthogonal mass spectrometry (MS) coupled to latency reversal bioassays, we identified gliotoxin (GTX) as a novel LRA. GTX significantly induced HIV-1 gene expression in latent ex vivo infected primary cells and in CD4+ T cells from all aviremic HIV-1+ participants. RNA sequencing identified 7SK RNA, the scaffold of the positive transcription elongation factor b (P-TEFb) inhibitory 7SK small nuclear ribonucleoprotein (snRNP) complex, to be significantly reduced upon GTX treatment of CD4+ T cells. GTX directly disrupted 7SK snRNP by targeting La-related protein 7 (LARP7), releasing active P-TEFb, which phosphorylated RNA polymerase II (Pol II) C-terminal domain (CTD), inducing HIV transcription.
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Affiliation(s)
- Mateusz Stoszko
- Department of Biochemistry, Erasmus MC University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, Netherlands
| | - Abdullah M. S. Al-Hatmi
- Westerdijk Fungal Biodiversity Institute, Utrecht, Netherlands
- Center of Expertise in Mycology of Radboud UMC/CWZ, Nijmegen, Netherlands
- Ministry of Health, Directorate General of Health Services, Ibri, Oman
| | - Anton Skriba
- Institute of Microbiology of the Czech Academy of Sciences, Videnska 1083, CZ 14220 Prague 4, Czech Republic
| | - Michael Roling
- Department of Biochemistry, Erasmus MC University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, Netherlands
| | - Enrico Ne
- Department of Biochemistry, Erasmus MC University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, Netherlands
| | - Raquel Crespo
- Department of Biochemistry, Erasmus MC University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, Netherlands
| | - Yvonne M. Mueller
- Department of Immunology, Erasmus MC University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, Netherlands
| | - Mohammad Javad Najafzadeh
- Westerdijk Fungal Biodiversity Institute, Utrecht, Netherlands
- Department of Parasitology and Mycology, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Joyce Kang
- Key Laboratory of Environmental Pollution Monitoring/Disease Control, Ministry of Education and Guizhou Talent Base of Microbes and Human Health, School of Basic Medicine, Guizhou Medical University, Guiyang 550025, P. R. China
| | - Renata Ptackova
- Institute of Microbiology of the Czech Academy of Sciences, Videnska 1083, CZ 14220 Prague 4, Czech Republic
| | - Elizabeth LeMasters
- Department of Biochemistry, Erasmus MC University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, Netherlands
| | - Pritha Biswas
- Department of Biochemistry, Erasmus MC University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, Netherlands
| | - Alessia Bertoldi
- Department of Biochemistry, Erasmus MC University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, Netherlands
- Microbiology Section, Department of Experimental, Diagnostic and Specialty Medicine, School of Medicine, University of Bologna, Bologna, Italy
| | - Tsung Wai Kan
- Department of Biochemistry, Erasmus MC University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, Netherlands
| | - Elisa de Crignis
- Department of Biochemistry, Erasmus MC University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, Netherlands
| | - Miroslav Sulc
- Institute of Microbiology of the Czech Academy of Sciences, Videnska 1083, CZ 14220 Prague 4, Czech Republic
| | - Joyce H.G. Lebbink
- Departments of Molecular Genetics and Radiation Oncology, Erasmus University Medical Center, PO Box 2040, 3000 CA Rotterdam, Netherlands
| | - Casper Rokx
- Department of Internal Medicine, Section of Infectious Diseases, Erasmus University Medical Center, PO Box 2040, 3000 CA, Rotterdam, Netherlands
| | - Annelies Verbon
- Department of Internal Medicine, Section of Infectious Diseases, Erasmus University Medical Center, PO Box 2040, 3000 CA, Rotterdam, Netherlands
| | - Wilfred van Ijcken
- Erasmus MC Genomics Core Facility, Department of Cell Biology, Erasmus University Medical Center, PO Box 2040, 3000 CA, Rotterdam, Netherlands
| | - Peter D. Katsikis
- Department of Immunology, Erasmus MC University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, Netherlands
| | - Robert-Jan Palstra
- Department of Biochemistry, Erasmus MC University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, Netherlands
| | - Vladimir Havlicek
- Institute of Microbiology of the Czech Academy of Sciences, Videnska 1083, CZ 14220 Prague 4, Czech Republic
| | - Sybren de Hoog
- Westerdijk Fungal Biodiversity Institute, Utrecht, Netherlands
- Center of Expertise in Mycology of Radboud UMC/CWZ, Nijmegen, Netherlands
| | - Tokameh Mahmoudi
- Department of Biochemistry, Erasmus MC University Medical Center Rotterdam, PO Box 2040, 3000 CA Rotterdam, Netherlands
- Corresponding author.
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Coleine C, Gevi F, Fanelli G, Onofri S, Timperio AM, Selbmann L. Specific adaptations are selected in opposite sun exposed Antarctic cryptoendolithic communities as revealed by untargeted metabolomics. PLoS One 2020; 15:e0233805. [PMID: 32460306 PMCID: PMC7253227 DOI: 10.1371/journal.pone.0233805] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2020] [Accepted: 05/12/2020] [Indexed: 12/18/2022] Open
Abstract
Antarctic cryptoendolithic communities are self-supporting borderline ecosystems spreading across the extreme conditions of the Antarctic desert and represent the predominant life-form in the ice-free areas of McMurdo Dry Valleys, accounted as the closest terrestrial Martian analogue. Components of these communities are highly adapted extremophiles and extreme-tolerant microorganisms, among the most resistant known to date. Recently, studies investigated biodiversity and community composition in these ecosystems but the metabolic activity of the metacommunity has never been investigated. Using an untargeted metabolomics, we explored stress-response of communities spreading in two sites of the same location, subjected to increasing environmental pressure due to opposite sun exposure, accounted as main factor influencing the diversity and composition of these ecosystems. Overall, 331 altered metabolites (206 and 125 unique for north and south, respectively), distinguished the two differently exposed communities. We also selected 10 metabolites and performed two-stage Receiver Operating Characteristic (ROC) analysis to test them as potential biomarkers. We further focused on melanin and allantoin as protective substances; their concentration was highly different in the community in the shadow or in the sun. These results clearly indicate that opposite insolation selected organisms in the communities with different adaptation strategies in terms of key metabolites produced.
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Affiliation(s)
- Claudia Coleine
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy
| | - Federica Gevi
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy
- Department of Science and Technology for Agriculture, Forestry, Nature and Energy, University of Tuscia, Viterbo, Italy
| | - Giuseppina Fanelli
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy
- Department of Science and Technology for Agriculture, Forestry, Nature and Energy, University of Tuscia, Viterbo, Italy
| | - Silvano Onofri
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy
| | - Anna Maria Timperio
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy
- Department of Science and Technology for Agriculture, Forestry, Nature and Energy, University of Tuscia, Viterbo, Italy
- * E-mail: (AMT); (LS)
| | - Laura Selbmann
- Department of Ecological and Biological Sciences, University of Tuscia, Viterbo, Italy
- Italian National Antarctic Museum (MNA), Mycological Section, Genoa, Italy
- * E-mail: (AMT); (LS)
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11
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Li X, Zhang B, Yan C, Li J, Wang S, Wei X, Jiang X, Zhou P, Fang J. A fast and specific fluorescent probe for thioredoxin reductase that works via disulphide bond cleavage. Nat Commun 2019; 10:2745. [PMID: 31227705 PMCID: PMC6588570 DOI: 10.1038/s41467-019-10807-8] [Citation(s) in RCA: 63] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Accepted: 05/31/2019] [Indexed: 12/31/2022] Open
Abstract
Small molecule probes are indispensable tools to explore diverse cellular events. However, finding a specific probe of a target remains a high challenge. Here we report the discovery of Fast-TRFS, a specific and superfast fluorogenic probe of mammalian thioredoxin reductase, a ubiquitous enzyme involved in regulation of diverse cellular redox signaling pathways. By systematically examining the processes of fluorophore release and reduction of cyclic disulfides/diselenides by the enzyme, structural factors that determine the response rate and specificity of the probe are disclosed. Mechanistic studies reveal that the fluorescence signal is switched on by a simple reduction of the disulfide bond within the probe, which is in stark contrast to the sensing mechanism of published probes. The favorable properties of Fast-TRFS enable development of a high-throughput screening assay to discover inhibitors of thioredoxin reductase by using crude tissue extracts as a source of the enzyme. Thioredoxin reductase (TrxR) plays a crucial part in regulating cellular redox homeostasis. Here, the authors developed a fluorescent probe composed of a five-membered disulphide, a coumarin fluorophore and a urea linker that detects TrxR activity with fast response and high selectivity.
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Affiliation(s)
- Xinming Li
- State Key Laboratory of Applied Organic Chemistry & College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, China
| | - Baoxin Zhang
- State Key Laboratory of Applied Organic Chemistry & College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, China
| | - Chaoxian Yan
- State Key Laboratory of Applied Organic Chemistry & College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, China
| | - Jin Li
- State Key Laboratory of Applied Organic Chemistry & College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, China
| | - Song Wang
- State Key Laboratory of Applied Organic Chemistry & College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, China
| | - Xiangxu Wei
- State Key Laboratory of Applied Organic Chemistry & College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, China
| | - Xiaoyan Jiang
- State Key Laboratory of Applied Organic Chemistry & College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, China
| | - Panpan Zhou
- State Key Laboratory of Applied Organic Chemistry & College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, China
| | - Jianguo Fang
- State Key Laboratory of Applied Organic Chemistry & College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, China.
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Ye W, Zhang W, Liu T, Huang Z, Zhu M, Chen Y, Li H, Li S. De Novo Transcriptome Sequencing of the Deep-Sea-Derived Fungus Dichotomomyces cejpii and Analysis of Gliotoxin Biosynthesis Genes. Int J Mol Sci 2018; 19:E1910. [PMID: 29966253 PMCID: PMC6073683 DOI: 10.3390/ijms19071910] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Revised: 06/17/2018] [Accepted: 06/26/2018] [Indexed: 12/03/2022] Open
Abstract
Gliotoxin, produced by fungi, is an epipolythiodioxopiperazine (ETP) toxin with bioactivities such as anti-liver fibrosis, antitumor, antifungus, antivirus, antioxidation, and immunoregulation. Recently, cytotoxic gliotoxins were isolated from a deep-sea-derived fungus, Dichotomomyces cejpii. However, the biosynthetic pathway for gliotoxins in D. cejpii remains unclear. In this study, the transcriptome of D. cejpii was sequenced using an Illumina Hiseq 2000. A total of 19,125 unigenes for D. cejpii were obtained from 9.73 GB of clean reads. Ten genes related to gliotoxin biosynthesis were annotated. The expression levels of gliotoxin-related genes were detected through quantitative real-time polymerase chain reaction (qRT-PCR). The GliG gene, encoding a glutathione S-transferase (DC-GST); GliI, encoding an aminotransferase (DC-AI); and GliO, encoding an aldehyde reductase (DC-AR), were cloned and expressed, purified, and characterized. The results suggested the important roles of DC-GST, DC-AT, and DC-AR in the biosynthesis of gliotoxins. Our study on the genes related to gliotoxin biosynthesis establishes a molecular foundation for the wider application of gliotoxins from D. cejpii in the biomedical industry in the future.
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Affiliation(s)
- Wei Ye
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, 100 Central Xianlie Road, Yuexiu District, Guangzhou 510070, China.
| | - Weimin Zhang
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, 100 Central Xianlie Road, Yuexiu District, Guangzhou 510070, China.
| | - Taomei Liu
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, 100 Central Xianlie Road, Yuexiu District, Guangzhou 510070, China.
| | - Zilei Huang
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, 100 Central Xianlie Road, Yuexiu District, Guangzhou 510070, China.
| | - Muzi Zhu
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, 100 Central Xianlie Road, Yuexiu District, Guangzhou 510070, China.
| | - Yuchan Chen
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, 100 Central Xianlie Road, Yuexiu District, Guangzhou 510070, China.
| | - Haohua Li
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, 100 Central Xianlie Road, Yuexiu District, Guangzhou 510070, China.
| | - Saini Li
- State Key Laboratory of Applied Microbiology Southern China, Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application, Guangdong Open Laboratory of Applied Microbiology, Guangdong Institute of Microbiology, 100 Central Xianlie Road, Yuexiu District, Guangzhou 510070, China.
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The Transcription Factor ZafA Regulates the Homeostatic and Adaptive Response to Zinc Starvation in Aspergillus fumigatus. Genes (Basel) 2018; 9:genes9070318. [PMID: 29949939 PMCID: PMC6070888 DOI: 10.3390/genes9070318] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 06/20/2018] [Accepted: 06/20/2018] [Indexed: 12/20/2022] Open
Abstract
One of the most important features that enables Aspergillus fumigatus to grow within a susceptible individual and to cause disease is its ability to obtain Zn2+ ions from the extremely zinc-limited environment provided by host tissues. Zinc uptake from this source in A. fumigatus relies on ZIP transporters encoded by the zrfA, zrfB and zrfC genes. The expression of these genes is tightly regulated by the ZafA transcription factor that regulates zinc homeostasis and is essential for A. fumigatus virulence. We combined the use of microarrays, Electrophoretic Mobility Shift Assays (EMSA) analyses, DNase I footprinting assays and in silico tools to better understand the regulation of the homeostatic and adaptive response of A. fumigatus to zinc starvation. We found that under zinc-limiting conditions, ZafA functions mainly as a transcriptional activator through binding to a zinc response sequence located in the regulatory regions of its target genes, although it could also function as a repressor of a limited number of genes. In addition to genes involved in the homeostatic response to zinc deficiency, ZafA also influenced, either directly or indirectly, the expression of many other genes. It is remarkable that the expression of many genes involved in iron uptake and ergosterol biosynthesis is strongly reduced under zinc starvation, even though only the expression of some of these genes appeared to be influenced directly or indirectly by ZafA. In addition, it appears to exist in A. fumigatus a zinc/iron cross-homeostatic network to allow the adaptation of the fungus to grow in media containing unbalanced Zn:Fe ratios. The adaptive response to oxidative stress typically linked to zinc starvation was also mediated by ZafA, as was the strong induction of genes involved in gliotoxin biosynthesis and self-protection against endogenous gliotoxin. This study has expanded our knowledge about the regulatory and metabolic changes displayed by A. fumigatus in response to zinc starvation and has helped us to pinpoint new ZafA target genes that could be important for fungal pathogens to survive and grow within host tissues and, hence, for virulence.
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Angelina C, Tan ISY, Choo Z, Lee OZJ, Pervaiz S, Chen ZX. KIF1Bβ increases ROS to mediate apoptosis and reinforces its protein expression through O 2- in a positive feedback mechanism in neuroblastoma. Sci Rep 2017; 7:16867. [PMID: 29203804 PMCID: PMC5715000 DOI: 10.1038/s41598-017-17192-6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2017] [Accepted: 11/22/2017] [Indexed: 01/15/2023] Open
Abstract
Relapse-prone, poor prognosis neuroblastoma is frequently characterized by deletion of chr1p36 where tumor suppressor gene KIF1Bβ resides. Interestingly, many 1p36-positive patients failed to express KIF1Bβ protein. Since altered cellular redox status has been reported to be involved in cell death and protein modification, we investigated the relationship between reactive oxygen species (ROS) and KIF1Bβ. Here, we showed that wild-type KIF1Bβ protein expression positively correlates with superoxide (O2-) and total ROS levels in neuroblastoma cells, unlike apoptotic loss-of-function KIF1Bβ mutants. Overexpression of KIF1Bβ apoptotic domain variants increases total ROS and, specifically O2-, whereas knockdown of endogenous KIF1Bβ decreases ROS and O2-. Interestingly, O2- increases KIF1Bβ protein expression, independent of the proteasomal degradation pathway. Scavenging O2- or ROS decreases KIF1Bβ protein expression and subsequent apoptosis. Moreover, treatment with investigational redox compound Gliotoxin increases O2-, KIF1Bβ protein expression, apoptosis and colony formation inhibition. Overall, our findings suggest that ROS and O2- may be important downstream effectors of KIF1Bβ-mediated apoptosis. Subsequently, O2- produced may increase KIF1Bβ protein expression in a positive feedback mechanism. Therefore, ROS and, specifically O2-, may be critical regulators of KIF1Bβ-mediated apoptosis and its protein expression in neuroblastoma.
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Affiliation(s)
- Clara Angelina
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Irene Sze Ying Tan
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Zhang'e Choo
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Oswald Zhao Jian Lee
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Shazib Pervaiz
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,NUS Graduate School for Integrative Sciences and Engineering, National University of Singapore, Singapore, Singapore.,Singapore-MIT Alliance, Singapore, Singapore
| | - Zhi Xiong Chen
- Department of Physiology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore. .,KK Women's and Children's Hospital, Singapore, Singapore.
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15
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Cairns T, Meyer V. In silico prediction and characterization of secondary metabolite biosynthetic gene clusters in the wheat pathogen Zymoseptoria tritici. BMC Genomics 2017; 18:631. [PMID: 28818040 PMCID: PMC5561558 DOI: 10.1186/s12864-017-3969-y] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2017] [Accepted: 07/31/2017] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND Fungal pathogens of plants produce diverse repertoires of secondary metabolites, which have functions ranging from iron acquisition, defense against immune perturbation, to toxic assaults on the host. The wheat pathogen Zymoseptoria tritici causes Septoria tritici blotch, a foliar disease which is a significant threat to global food security. Currently, there is limited knowledge of the secondary metabolite arsenal produced by Z. tritici, which significantly restricts mechanistic understanding of infection. In this study, we analyzed the genome of Z. tritici isolate IP0323 to identify putative secondary metabolite biosynthetic gene clusters, and used comparative genomics to predict their encoded products. RESULTS We identified 32 putative secondary metabolite clusters. These were physically enriched at subtelomeric regions, which may facilitate diversification of cognate products by rapid gene rearrangement or mutations. Comparative genomics revealed a four gene cluster with significant similarity to the ferrichrome-A biosynthetic locus of the maize pathogen Ustilago maydis, suggesting this siderophore is deployed by Z. tritici to acquire iron. The Z. tritici genome also contains several isoprenoid biosynthetic gene clusters, including one with high similarity to a carotenoid/opsin producing locus in several fungi. Furthermore, we identify putative phytotoxin biosynthetic clusters, suggesting Z. tritici can produce an epipolythiodioxopiperazine, and a polyketide and non-ribosomal peptide with predicted structural similarities to fumonisin and the Alternaria alternata AM-toxin, respectively. Interrogation of an existing transcriptional dataset suggests stage specific deployment of numerous predicted loci during infection, indicating an important role of these secondary metabolites in Z. tritici disease. CONCLUSIONS We were able to assign putative biosynthetic products to numerous clusters based on conservation amongst other fungi. However, analysis of the majority of secondary metabolite loci did not enable prediction of a cluster product, and consequently the capacity of these loci to play as yet undetermined roles in disease or other stages of the Z. tritici lifecycle is significant. These data will drive future experimentation for determining the role of these clusters and cognate secondary metabolite products in Z. tritici virulence, and may lead to discovery of novel bioactive molecules.
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Affiliation(s)
- Timothy Cairns
- Institute of Biotechnology, Department of Applied and Molecular Microbiology, Berlin University of Technology, Gustav-Meyer-Allee 25, 13355, Berlin, Germany.
| | - Vera Meyer
- Institute of Biotechnology, Department of Applied and Molecular Microbiology, Berlin University of Technology, Gustav-Meyer-Allee 25, 13355, Berlin, Germany
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16
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Wang Y, Hu P, Pan Y, Zhu Y, Liu X, Che Y, Liu G. Identification and characterization of the verticillin biosynthetic gene cluster in Clonostachys rogersoniana. Fungal Genet Biol 2017; 103:25-33. [DOI: 10.1016/j.fgb.2017.03.007] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Revised: 03/24/2017] [Accepted: 03/27/2017] [Indexed: 01/29/2023]
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17
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Garg N, Luzzatto-Knaan T, Melnik AV, Caraballo-Rodríguez AM, Floros DJ, Petras D, Gregor R, Dorrestein PC, Phelan VV. Natural products as mediators of disease. Nat Prod Rep 2017; 34:194-219. [PMID: 27874907 PMCID: PMC5299058 DOI: 10.1039/c6np00063k] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Covering: up to 2016Humans are walking microbial ecosystems, each harboring a complex microbiome with the genetic potential to produce a vast array of natural products. Recent sequencing data suggest that our microbial inhabitants are critical for maintaining overall health. Shifts in microbial communities have been correlated to a number of diseases including infections, inflammation, cancer, and neurological disorders. Some of these clinically and diagnostically relevant phenotypes are a result of the presence of small molecules, yet we know remarkably little about their contributions to the health of individuals. Here, we review microbe-derived natural products as mediators of human disease.
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Affiliation(s)
- Neha Garg
- Collaborative Mass Spectrometry Innovation Center, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093
| | - Tal Luzzatto-Knaan
- Collaborative Mass Spectrometry Innovation Center, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093
| | - Alexey V. Melnik
- Collaborative Mass Spectrometry Innovation Center, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093
| | | | - Dimitrios J. Floros
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA 92093
| | - Daniel Petras
- Collaborative Mass Spectrometry Innovation Center, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093
| | - Rachel Gregor
- Department of Chemistry and the National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Be’er Sheva 84105, Israel
| | - Pieter C. Dorrestein
- Collaborative Mass Spectrometry Innovation Center, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093
| | - Vanessa V. Phelan
- Collaborative Mass Spectrometry Innovation Center, Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA 92093
- Department of Pharmaceutical Sciences, Skaggs School of Pharmacy and Pharmaceutical Sciences, The University of Colorado Anschutz Medical Campus, Aurora, CO 80045
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Scharf DH, Brakhage AA, Mukherjee PK. Gliotoxin--bane or boon? Environ Microbiol 2015; 18:1096-109. [PMID: 26443473 DOI: 10.1111/1462-2920.13080] [Citation(s) in RCA: 67] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Revised: 09/30/2015] [Accepted: 10/04/2015] [Indexed: 12/31/2022]
Abstract
Gliotoxin (GT) is the most important epidithiodioxopiperazine (ETP)-type fungal toxin. GT was originally isolated from Trichoderma species as an antibiotic substance involved in biological control of plant pathogenic fungi. A few isolates of GT-producing Trichoderma virens are commercially marketed for biological control and widely used in agriculture. Furthermore, GT is long known as an immunosuppressive agent and also reported to have anti-tumour properties. However, recent publications suggest that GT is a virulence determinant of the human pathogen Aspergillus fumigatus. This compound is thus important on several counts - it has medicinal properties, is a pathogenicity determinant, is a potential diagnostic marker and is important in biological crop protection. The present article addresses this paradox and the ecological role of GT. We discuss the function of GT as defence molecule, the role in aspergillosis and suggest solutions for safe application of Trichoderma-based biofungicides.
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Affiliation(s)
- Daniel H Scharf
- Department of Molecular and Applied Microbiology, Leibniz-Institute for Natural Product Research and Infection Biology, Hans Knoell Institute (HKI) and Institute for Microbiology, Friedrich Schiller University Jena, Beutenbergstr. 11a, 07745, Jena, Germany
| | - Axel A Brakhage
- Department of Molecular and Applied Microbiology, Leibniz-Institute for Natural Product Research and Infection Biology, Hans Knoell Institute (HKI) and Institute for Microbiology, Friedrich Schiller University Jena, Beutenbergstr. 11a, 07745, Jena, Germany
| | - Prasun K Mukherjee
- Nuclear Agriculture and Biotechnology Division, Bhabha Atomic Research Centre, Trombay, Mumbai, 400085, India
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Interplay between Gliotoxin Resistance, Secretion, and the Methyl/Methionine Cycle in Aspergillus fumigatus. EUKARYOTIC CELL 2015; 14:941-57. [PMID: 26150413 DOI: 10.1128/ec.00055-15] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2015] [Accepted: 06/30/2015] [Indexed: 01/20/2023]
Abstract
Mechanistic studies on gliotoxin biosynthesis and self-protection in Aspergillus fumigatus, both of which require the gliotoxin oxidoreductase GliT, have revealed a rich landscape of highly novel biochemistries, yet key aspects of this complex molecular architecture remain obscure. Here we show that an A. fumigatus ΔgliA strain is completely deficient in gliotoxin secretion but still retains the ability to efflux bisdethiobis(methylthio)gliotoxin (BmGT). This correlates with a significant increase in sensitivity to exogenous gliotoxin because gliotoxin trapped inside the cell leads to (i) activation of the gli cluster, as disabling gli cluster activation, via gliZ deletion, attenuates the sensitivity of an A. fumigatus ΔgliT strain to gliotoxin, thus implicating cluster activation as a factor in gliotoxin sensitivity, and (ii) increased methylation activity due to excess substrate (dithiol gliotoxin) for the gliotoxin bis-thiomethyltransferase GtmA. Intracellular dithiol gliotoxin is oxidized by GliT and subsequently effluxed by GliA. In the absence of GliA, gliotoxin persists in the cell and is converted to BmGT, with levels significantly higher than those in the wild type. Similarly, in the ΔgliT strain, gliotoxin oxidation is impeded, and methylation occurs unchecked, leading to significant S-adenosylmethionine (SAM) depletion and S-adenosylhomocysteine (SAH) overproduction. This in turn significantly contributes to the observed hypersensitivity of gliT-deficient A. fumigatus to gliotoxin. Our observations reveal a key role for GliT in preventing dysregulation of the methyl/methionine cycle to control intracellular SAM and SAH homeostasis during gliotoxin biosynthesis and exposure. Moreover, we reveal attenuated GliT abundance in the A. fumigatus ΔgliK strain, but not the ΔgliG strain, following exposure to gliotoxin, correlating with relative sensitivities. Overall, we illuminate new systems interactions that have evolved in gliotoxin-producing, compared to gliotoxin-naive, fungi to facilitate their cellular presence.
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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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Redox metabolites signal polymicrobial biofilm development via the NapA oxidative stress cascade in Aspergillus. Curr Biol 2014; 25:29-37. [PMID: 25532893 DOI: 10.1016/j.cub.2014.11.018] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Revised: 10/15/2014] [Accepted: 11/06/2014] [Indexed: 01/19/2023]
Abstract
BACKGROUND Filamentous fungi and bacteria form mixed-species biofilms in nature and diverse clinical contexts. They secrete a wealth of redox-active small molecule secondary metabolites, which are traditionally viewed as toxins that inhibit growth of competing microbes. RESULTS Here, we report that these "toxins" can act as interspecies signals, affecting filamentous fungal development via oxidative stress regulation. Specifically, in coculture biofilms, Pseudomonas aeruginosa phenazine-derived metabolites differentially modulated Aspergillus fumigatus development, shifting from weak vegetative growth to induced asexual sporulation (conidiation) along a decreasing phenazine gradient. The A. fumigatus morphological shift correlated with the production of phenazine radicals and concomitant reactive oxygen species (ROS) production generated by phenazine redox cycling. Phenazine conidiation signaling was conserved in the genetic model A. nidulans and mediated by NapA, a homolog of AP-1-like bZIP transcription factor, which is essential for the response to oxidative stress in humans, yeast, and filamentous fungi. Expression profiling showed phenazine treatment induced a NapA-dependent response of the global oxidative stress metabolome, including the thioredoxin, glutathione, and NADPH-oxidase systems. Conidiation induction in A. nidulans by another microbial redox-active secondary metabolite, gliotoxin, also required NapA. CONCLUSIONS This work highlights that microbial redox metabolites are key signals for sporulation in filamentous fungi, which are communicated through an evolutionarily conserved eukaryotic stress response pathway. It provides a foundation for interspecies signaling in environmental and clinical biofilms involving bacteria and filamentous fungi.
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O'Keeffe G, Hammel S, Owens RA, Keane TM, Fitzpatrick DA, Jones GW, Doyle S. RNA-seq reveals the pan-transcriptomic impact of attenuating the gliotoxin self-protection mechanism in Aspergillus fumigatus. BMC Genomics 2014; 15:894. [PMID: 25311525 PMCID: PMC4209032 DOI: 10.1186/1471-2164-15-894] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Accepted: 10/07/2014] [Indexed: 11/21/2022] Open
Abstract
Background Aspergillus fumigatus produces a number of secondary metabolites, one of which, gliotoxin, has been shown to exhibit anti-fungal activity. Thus, A. fumigatus must be able to protect itself against gliotoxin. Indeed one of the genes in the gliotoxin biosynthetic gene cluster in A. fumigatus, gliT, is required for self-protection against the toxin- however the global self-protection mechanism deployed is unclear. RNA-seq was employed to identify genes differentially regulated upon exposure to gliotoxin in A. fumigatus wild-type and A. fumigatus ∆gliT, a strain that is hypersensitive to gliotoxin. Results Deletion of A. fumigatus gliT resulted in altered expression of 208 genes (log2 fold change of 1.5) when compared to A. fumigatus wild-type, of which 175 genes were up-regulated and 33 genes were down-regulated. Expression of 164 genes was differentially regulated (log2 fold change of 1.5) in A. fumigatus wild-type when exposed to gliotoxin, consisting of 101 genes with up-regulated expression and 63 genes with down-regulated expression. Interestingly, a much larger number of genes, 1700, were found to be differentially regulated (log2 fold change of 1.5) in A. fumigatus ∆gliT when challenged with gliotoxin. These consisted of 508 genes with up-regulated expression, and 1192 genes with down-regulated expression. Functional Catalogue (FunCat) classification of differentially regulated genes revealed an enrichment of genes involved in both primary metabolic functions and secondary metabolism. Specifically, genes involved in gliotoxin biosynthesis, helvolic acid biosynthesis, siderophore-iron transport genes and also nitrogen metabolism genes and ribosome biogenesis genes underwent altered expression. It was confirmed that gliotoxin biosynthesis is induced upon exposure to exogenous gliotoxin, production of unrelated secondary metabolites is attenuated in A. fumigatus ∆gliT, while quantitative proteomic analysis confirmed disrupted translation in A. fumigatus ∆gliT challenged with exogenous gliotoxin. Conclusions This study presents the first global investigation of the transcriptional response to exogenous gliotoxin in A. fumigatus wild-type and the hyper-sensitive strain, ∆gliT. Our data highlight the global and extensive affects of exogenous gliotoxin on a sensitive strain devoid of a self-protection mechanism and infer that GliT functionality is required for the optimal biosynthesis of selected secondary metabolites in A. fumigatus. Electronic supplementary material The online version of this article (doi:10.1186/1471-2164-15-894) contains supplementary material, which is available to authorized users.
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Affiliation(s)
| | | | | | | | | | | | - Sean Doyle
- Department of Biology, National University of Ireland Maynooth, Maynooth, Co, Kildare, Ireland.
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Owens RA, Hammel S, Sheridan KJ, Jones GW, Doyle S. A proteomic approach to investigating gene cluster expression and secondary metabolite functionality in Aspergillus fumigatus. PLoS One 2014; 9:e106942. [PMID: 25198175 PMCID: PMC4157829 DOI: 10.1371/journal.pone.0106942] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Accepted: 08/11/2014] [Indexed: 11/18/2022] Open
Abstract
A combined proteomics and metabolomics approach was utilised to advance the identification and characterisation of secondary metabolites in Aspergillus fumigatus. Here, implementation of a shotgun proteomic strategy led to the identification of non-redundant mycelial proteins (n = 414) from A. fumigatus including proteins typically under-represented in 2-D proteome maps: proteins with multiple transmembrane regions, hydrophobic proteins and proteins with extremes of molecular mass and pI. Indirect identification of secondary metabolite cluster expression was also achieved, with proteins (n = 18) from LaeA-regulated clusters detected, including GliT encoded within the gliotoxin biosynthetic cluster. Biochemical analysis then revealed that gliotoxin significantly attenuates H2O2-induced oxidative stress in A. fumigatus (p>0.0001), confirming observations from proteomics data. A complementary 2-D/LC-MS/MS approach further elucidated significantly increased abundance (p<0.05) of proliferating cell nuclear antigen (PCNA), NADH-quinone oxidoreductase and the gliotoxin oxidoreductase GliT, along with significantly attenuated abundance (p<0.05) of a heat shock protein, an oxidative stress protein and an autolysis-associated chitinase, when gliotoxin and H2O2 were present, compared to H2O2 alone. Moreover, gliotoxin exposure significantly reduced the abundance of selected proteins (p<0.05) involved in de novo purine biosynthesis. Significantly elevated abundance (p<0.05) of a key enzyme, xanthine-guanine phosphoribosyl transferase Xpt1, utilised in purine salvage, was observed in the presence of H2O2 and gliotoxin. This work provides new insights into the A. fumigatus proteome and experimental strategies, plus mechanistic data pertaining to gliotoxin functionality in the organism.
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Affiliation(s)
- Rebecca A. Owens
- Department of Biology, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland
| | - Stephen Hammel
- Department of Biology, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland
| | - Kevin J. Sheridan
- Department of Biology, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland
| | - Gary W. Jones
- Department of Biology, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland
| | - Sean Doyle
- Department of Biology, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland
- * E-mail:
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24
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Vargas WA, Mukherjee PK, Laughlin D, Wiest A, Moran-Diez ME, Kenerley CM. Role of gliotoxin in the symbiotic and pathogenic interactions of Trichoderma virens. MICROBIOLOGY-SGM 2014; 160:2319-2330. [PMID: 25082950 DOI: 10.1099/mic.0.079210-0] [Citation(s) in RCA: 54] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Using a gene disruption strategy, we generated mutants in the gliP locus of the plant-beneficial fungus Trichoderma virens that were no longer capable of producing gliotoxin. Phenotypic assays demonstrated that the gliP-disrupted mutants grew faster, were more sensitive to oxidative stress and exhibited a sparse colony edge compared with the WT strain. In a plate confrontation assay, the mutants deficient in gliotoxin production were ineffective as mycoparasites against the oomycete, Pythium ultimum, and the necrotrophic fungal pathogen, Sclerotinia sclerotiorum, but retained mycoparasitic ability against Rhizoctonia solani. Biocontrol assays in soil showed that the mutants were incapable of protecting cotton seedlings from attack by P. ultimum, against which the WT strain was highly effective. The mutants, however, were as effective as the WT strain in protecting cotton seedlings against R. solani. Loss of gliotoxin production also resulted in a reduced ability of the mutants to attack the sclerotia of S. sclerotiorum compared with the WT. The addition of exogenous gliotoxin to the sclerotia colonized by the mutants partially restored their degradative abilities. Interestingly, as in Aspergillus fumigatus, an opportunistic human pathogen, gliotoxin was found to be involved in pathogenicity of T. virens against larvae of the wax moth, Galleria mellonella. The loss of gliotoxin production in T. virens was restored by complementation with the gliP gene from A. fumigatus. We have, thus, demonstrated that the putative gliP cluster of T. virens is responsible for the biosynthesis of gliotoxin, and gliotoxin is involved in mycoparasitism and biocontrol properties of this plant-beneficial fungus.
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Affiliation(s)
- Walter A Vargas
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI), Universidad Nacional de Rosario, Suipacha 531, Rosario 2000, Argentina
| | - Prasun K Mukherjee
- Nuclear Agriculture and Biotechnology Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400085, India
| | - David Laughlin
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX 77843-2132, USA
| | - Aric Wiest
- Fungal Genetics Stock Center, University of Missouri-Kansas City, Kansas City, MO 64110, USA
| | - Maria E Moran-Diez
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX 77843-2132, USA
| | - Charles M Kenerley
- Department of Plant Pathology and Microbiology, Texas A&M University, College Station, TX 77843-2132, USA
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25
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Ben-Ami R. Angiogenesis at the mold-host interface: a potential key to understanding and treating invasive aspergillosis. Future Microbiol 2014; 8:1453-62. [PMID: 24199803 DOI: 10.2217/fmb.13.114] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Invasive aspergillosis (IA) in neutropenic patients is characterized by angioinvasion, intravascular thrombosis and tissue infarction, features that lead to sequestration of infected tissue and impaired fungal clearance. Recent research has shown that host angiogenesis, the homeostatic compensatory response to tissue hypoxia, is downregulated by Aspergillus fumigatus secondary metabolites. A. fumigatus metabolites inhibit multiple key angiogenic mediators, notably basic FGF, VEGF and their respective receptors. Moreover, repletion of basic FGF and VEGF enhances angiogenesis at the site of infection, induces trafficking of polymorphonuclear leukocytes into fungal-infected tissue and enhances antifungal drug activity. This review summarizes the emerging roles of vasculopathy and angiogenesis in the pathogenesis of IA, emphasizing the importance of the underlying mode of immunosuppression. Modulation of angiogenesis is a potential target for novel therapeutic strategies against IA.
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Affiliation(s)
- Ronen Ben-Ami
- Infectious Diseases Unit, Tel Aviv Medical Center & the Sackler School of Medicine, Tel Aviv University, Israel.
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26
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The mtfA transcription factor gene controls morphogenesis, gliotoxin production, and virulence in the opportunistic human pathogen Aspergillus fumigatus. EUKARYOTIC CELL 2014; 13:766-75. [PMID: 24728192 DOI: 10.1128/ec.00075-14] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Aspergillus fumigatus is the leading causative agent of invasive aspergillosis (IA). The number of cases is on the rise, with mortality rates as high as 90% among immunocompromised patients. Molecular genetic studies in A. fumigatus could provide novel targets to potentially set the basis for antifungal therapies. In the current study, we investigated the role of the transcription factor gene mtfA in A. fumigatus. Our results revealed that mtfA plays a role in the growth and development of the fungus. Deletion or overexpression of mtfA leads to a slight reduction in colony growth, as well as a reduction in conidiation levels, in the overexpression strain compared to the wild-type strain. Furthermore, production of the secondary metabolite gliotoxin increased when mtfA was overexpressed, coinciding with an increase in the transcription levels of the gliotoxin genes gliZ and gliP with respect to the wild type. In addition, our study showed that mtfA is also necessary for normal protease activity in A. fumigatus; deletion of mtfA resulted in a reduction of protease activity compared to wild-type levels. Importantly, the absence of mtfA caused a decrease in virulence in the Galleria mellonella infection model, indicating that mtfA is necessary for A. fumigatus wild-type pathogenesis.
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Kang DH, Lee DJ, Kim J, Lee JY, Kim HW, Kwon K, Taylor WR, Jo H, Kang SW. Vascular injury involves the overoxidation of peroxiredoxin type II and is recovered by the peroxiredoxin activity mimetic that induces reendothelialization. Circulation 2013; 128:834-44. [PMID: 23820076 DOI: 10.1161/circulationaha.113.001725] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
BACKGROUND Typical 2-Cys peroxiredoxin (Prx) is inactivated by overoxidation of the peroxidatic cysteine residue under oxidative stress. However, the significance in the context of vascular disease is unknown. METHODS AND RESULTS Immunohistochemical analyses revealed that 2-Cys Prxs, particularly Prx type II, are heavily overoxidized in balloon-injured rodent carotid vessels and in human atherosclerotic lesions. Consistent with this observation, the selective depletion of Prx II exacerbated neointimal hyperplasia in injured carotid vessels. We also found that the epipolythiodioxopiperazine class of fungal metabolites exhibited an enzyme-like activity mimicking 2-Cys Prx peroxidase and manifestly eliminated the intracellular H₂O₂ in the vascular cells. Functionally, the epipolythiodioxopiperazines reciprocally regulated the platelet-derived growth factor receptor-β- and vascular endothelial growth factor receptor-mediated signaling in these vascular cells by replacing Prx II. As a consequence, the epipolythiodioxopiperazines inhibited the proliferative and migratory activities of smooth muscle cells but promoted those of endothelial cells in vitro. Moreover, administration of the epipolythiodioxopiperazines to the injured carotid vessels resulted in a successful recovery by inhibiting neointimal hyperplasia without causing cytotoxicity and simultaneously inducing reendothelialization. CONCLUSIONS This study reveals for the first time the involvement of the 2-Cys Prx overoxidation and thus the therapeutic use of their activity mimetic in vascular injuries like stenting.
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Affiliation(s)
- Dong Hoon Kang
- Division of Life and Pharmaceutical Science and Center for Cell Signaling and Drug Discovery Research, Ewha Womans University, Seoul, Korea
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28
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Lee DJ, Kang DH, Choi M, Choi YJ, Lee JY, Park JH, Park YJ, Lee KW, Kang SW. Peroxiredoxin-2 represses melanoma metastasis by increasing E-Cadherin/β-Catenin complexes in adherens junctions. Cancer Res 2013; 73:4744-57. [PMID: 23749642 DOI: 10.1158/0008-5472.can-12-4226] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In melanoma, transition to the vertical growth phase is the critical step in conversion to a deadly malignant disease. Here, we offer the first evidence that an antioxidant enzyme has a key role in this transition. We found that the antioxidant enzyme peroxiredoxin-2 (Prx2) inversely correlated with the metastatic capacity of human melanoma cells. Silencing Prx2 expression stimulated proliferation and migration, whereas ectopic expression of Prx2 produced the opposite effect. Mechanistic investigations indicated that Prx2 negatively regulated Src/ERK activation status, which in turn fortified adherens junctions function by increasing E-cadherin expression and phospho-Y654-dependent retention of β-catenin in the plasma membrane. In murine melanoma cells, Prx2 silencing enhanced lung metastasis in vivo. Interestingly, the natural compound gliotoxin, which is known to exert a Prx-like activity, inhibited proliferation and migration as well as lung metastasis of Prx2-deficient melanoma cells. Overall, our findings reveal that Prx2 is a key regulator of invasion and metastasis in melanoma, and also suggest a pharmacologic strategy to effectively decrease deadly malignant forms of this disease.
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Affiliation(s)
- Doo Jae Lee
- Division of Life and Pharmaceutical Sciences, Ewha Womans University, Seoul, Republic of Korea
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29
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The Aspergillus fumigatus protein GliK protects against oxidative stress and is essential for gliotoxin biosynthesis. EUKARYOTIC CELL 2012; 11:1226-38. [PMID: 22903976 DOI: 10.1128/ec.00113-12] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The function of a number of genes in the gliotoxin biosynthetic cluster (gli) in Aspergillus fumigatus remains unknown. Here, we demonstrate that gliK deletion from two strains of A. fumigatus completely abolished gliotoxin biosynthesis. Furthermore, exogenous H(2)O(2) (1 mM), but not gliotoxin, significantly induced A. fumigatus gliK expression (P = 0.0101). While both mutants exhibited significant sensitivity to both exogenous gliotoxin (P < 0.001) and H(2)O(2) (P < 0.01), unexpectedly, exogenous gliotoxin relieved H(2)O(2)-induced growth inhibition in a dose-dependent manner (0 to 10 μg/ml). Gliotoxin-containing organic extracts derived from A. fumigatus ATCC 26933 significantly inhibited (P < 0.05) the growth of the ΔgliK(26933) deletion mutant. The A. fumigatus ΔgliK(26933) mutant secreted metabolites, devoid of disulfide linkages or free thiols, that were detectable by reverse-phase high-performance liquid chromatography and liquid chromatography-mass spectrometry with m/z 394 to 396. These metabolites (m/z 394 to 396) were present at significantly higher levels in the culture supernatants of the A. fumigatus ΔgliK(26933) mutant than in those of the wild type (P = 0.0024 [fold difference, 24] and P = 0.0003 [fold difference, 9.6], respectively) and were absent from A. fumigatus ΔgliG. Significantly elevated levels of ergothioneine were present in aqueous mycelial extracts of the A. fumigatus ΔgliK(26933) mutant compared to the wild type (P < 0.001). Determination of the gliotoxin uptake rate revealed a significant difference (P = 0.0045) between that of A. fumigatus ATCC 46645 (9.3 pg/mg mycelium/min) and the ΔgliK(46645) mutant (31.4 pg/mg mycelium/min), strongly suggesting that gliK absence and the presence of elevated ergothioneine levels impede exogenously added gliotoxin efflux. Our results confirm a role for gliK in gliotoxin biosynthesis and reveal new insights into gliotoxin functionality in A. fumigatus.
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Abstract
Chaetocin, a natural product isolated from fungi of Chaetomium species, is a member of the epipolythiodiketopiperazines (ETPs), which have various biological activities, including cytostatic and anticancer activities. Recently, the inhibitory activity toward histone methyltransferases (HMTs) was discovered for chaetocin. We previously reported the first total synthesis of chaetocin and various derivatives. During studies on the structure–activity relationship for HMT inhibition, we found that the enantiomer of chaetocin (ent-chaetocin) is a more potent apoptosis inducer than natural chaetocin in human leukemia HL-60 cells. Mechanistic studies showed that ent-chaetocin induces apoptosis through the caspase-8/caspase-3 pathway.
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31
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Carberry S, Molloy E, Hammel S, O’Keeffe G, Jones GW, Kavanagh K, Doyle S. Gliotoxin effects on fungal growth: Mechanisms and exploitation. Fungal Genet Biol 2012; 49:302-12. [DOI: 10.1016/j.fgb.2012.02.003] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2011] [Revised: 02/09/2012] [Accepted: 02/10/2012] [Indexed: 10/28/2022]
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32
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The role of glutathione S-transferase GliG in gliotoxin biosynthesis in Aspergillus fumigatus. ACTA ACUST UNITED AC 2011; 18:542-52. [PMID: 21513890 DOI: 10.1016/j.chembiol.2010.12.022] [Citation(s) in RCA: 70] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2010] [Revised: 12/15/2010] [Accepted: 12/29/2010] [Indexed: 01/29/2023]
Abstract
Gliotoxin, a redox-active metabolite, is produced by the opportunistic fungal pathogen Aspergillus fumigatus, and its biosynthesis is directed by the gli gene cluster. Knowledge of the biosynthetic pathway to gliotoxin, which contains a disulfide bridge of unknown origin, is limited, although L-Phe and L-Ser are known biosynthetic precursors. Deletion of gliG from the gli cluster, herein functionally confirmed as a glutathione S-transferase, results in abrogation of gliotoxin biosynthesis and accumulation of 6-benzyl-6-hydroxy-1-methoxy-3-methylenepiperazine-2,5-dione. This putative shunt metabolite from the gliotoxin biosynthetic pathway contains an intriguing hydroxyl group at C-6, consistent with a gliotoxin biosynthetic pathway involving thiolation via addition of the glutathione thiol group to a reactive acyl imine intermediate. Complementation of gliG restored gliotoxin production and, unlike gliT, gliG was found not to be involved in fungal self-protection against gliotoxin.
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Davis C, Gordon N, Murphy S, Singh I, Kavanagh K, Carberry S, Doyle S. Single-pot derivatisation strategy for enhanced gliotoxin detection by HPLC and MALDI-ToF mass spectrometry. Anal Bioanal Chem 2011; 401:2519-29. [DOI: 10.1007/s00216-011-5344-1] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2011] [Revised: 08/12/2011] [Accepted: 08/16/2011] [Indexed: 11/28/2022]
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34
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Ben-Ami R, Lewis RE, Kontoyiannis DP. Enemy of the (immunosuppressed) state: an update on the pathogenesis of Aspergillus fumigatus infection. Br J Haematol 2010; 150:406-17. [PMID: 20618330 DOI: 10.1111/j.1365-2141.2010.08283.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Aspergillus fumigatus is an opportunistic filamentous fungus that is currently the most frequent cause of invasive fungal disease in immunosuppressed individuals. Recent advances in our understanding of the pathogenesis of invasive aspergillosis have highlighted the multifactorial nature of A. fumigatus virulence and the complex interplay between host and microbial factors. In this review, we outline current concepts of immune recognition and evasion, angioinvasion and angiogenesis, secondary metabolism and the fungal stress response, and their respective roles in this often lethal infection.
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Affiliation(s)
- Ronen Ben-Ami
- Infectious Diseases Unit, Tel Aviv Sourasky Medical Center, Tel Aviv, Israel
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35
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Schrettl M, Carberry S, Kavanagh K, Haas H, Jones GW, O'Brien J, Nolan A, Stephens J, Fenelon O, Doyle S. Self-protection against gliotoxin--a component of the gliotoxin biosynthetic cluster, GliT, completely protects Aspergillus fumigatus against exogenous gliotoxin. PLoS Pathog 2010; 6:e1000952. [PMID: 20548963 PMCID: PMC2883607 DOI: 10.1371/journal.ppat.1000952] [Citation(s) in RCA: 138] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2009] [Accepted: 05/12/2010] [Indexed: 11/29/2022] Open
Abstract
Gliotoxin, and other related molecules, are encoded by multi-gene clusters and biosynthesized by fungi using non-ribosomal biosynthetic mechanisms. Almost universally described in terms of its toxicity towards mammalian cells, gliotoxin has come to be considered as a component of the virulence arsenal of Aspergillus fumigatus. Here we show that deletion of a single gene, gliT, in the gliotoxin biosynthetic cluster of two A. fumigatus strains, rendered the organism highly sensitive to exogenous gliotoxin and completely disrupted gliotoxin secretion. Addition of glutathione to both A. fumigatus ΔgliT strains relieved gliotoxin inhibition. Moreover, expression of gliT appears to be independently regulated compared to all other cluster components and is up-regulated by exogenous gliotoxin presence, at both the transcript and protein level. Upon gliotoxin exposure, gliT is also expressed in A. fumigatus ΔgliZ, which cannot express any other genes in the gliotoxin biosynthetic cluster, indicating that gliT is primarily responsible for protecting this strain against exogenous gliotoxin. GliT exhibits a gliotoxin reductase activity up to 9 µM gliotoxin and appears to prevent irreversible depletion of intracellular glutathione stores by reduction of the oxidized form of gliotoxin. Cross-species resistance to exogenous gliotoxin is acquired by A. nidulans and Saccharomyces cerevisiae, respectively, when transformed with gliT. We hypothesise that the primary role of gliotoxin may be as an antioxidant and that in addition to GliT functionality, gliotoxin secretion may be a component of an auto-protective mechanism, deployed by A. fumigatus to protect itself against this potent biomolecule. The pathogenic fungus Aspergillus fumigatus causes disease in immunocompromised individuals such as cancer patients. The fungus makes a small molecule called gliotoxin which helps A. fumigatus bypass the immune system in ill people, and cause disease. Although a small molecule, gliotoxin biosynthesis is enabled by a complex series of enzymes, one of which is called GliT, in A. fumigatus. Amazingly, nobody has really considered that gliotoxin might be toxic to A. fumigatus itself. Here we show that absence of GliT makes A. fumigatus highly sensitive to added gliotoxin and inhibits fungal growth, both of which can be reversed by restoring GliT. Neither can the fungus make or release its own gliotoxin when GliT is missing. We also show that gliotoxin sensitivity can be totally overcome by adding glutathione, which is an important anti-oxidant within cells. We demonstrate that gliotoxin addition increases the production of GliT, and that GliT breaks the disulphide bond in gliotoxin which may be a step in the pathway for gliotoxin protection or release from A. fumigatus. We conclude that gliotoxin may mainly be involved in protecting A. fumigatus against oxidative stress and that it is an accidental toxin.
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Affiliation(s)
- Markus Schrettl
- Department of Biology and National Institute for Cellular Biotechnology, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland
- Biocenter-Division of Molecular Biology, Innsbruck Medical University, Innsbruck, Austria
| | - Stephen Carberry
- Department of Biology and National Institute for Cellular Biotechnology, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland
| | - Kevin Kavanagh
- Department of Biology and National Institute for Cellular Biotechnology, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland
| | - Hubertus Haas
- Biocenter-Division of Molecular Biology, Innsbruck Medical University, Innsbruck, Austria
| | - Gary W. Jones
- Department of Biology and National Institute for Cellular Biotechnology, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland
| | - Jennifer O'Brien
- Department of Biology and National Institute for Cellular Biotechnology, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland
| | - Aine Nolan
- Department of Biology and National Institute for Cellular Biotechnology, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland
| | - John Stephens
- Department of Chemistry, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland
| | - Orla Fenelon
- Department of Chemistry, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland
| | - Sean Doyle
- Department of Biology and National Institute for Cellular Biotechnology, National University of Ireland Maynooth, Maynooth, Co. Kildare, Ireland
- * E-mail:
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Brunati AM, Pagano MA, Bindoli A, Rigobello MP. Thiol redox systems and protein kinases in hepatic stellate cell regulatory processes. Free Radic Res 2010; 44:363-78. [PMID: 20166884 DOI: 10.3109/10715760903555836] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Hepatic stellate cells (HSC) are the major producers of collagen in the liver and their conversion from resting cells to a proliferating, contractile and fibrogenic phenotype ('activation') is a critical step, leading to liver fibrosis characterized by deposition of excessive extracellular matrix. Cytokines, growth factors, reactive oxygen and nitrogen species (ROS/RNS), lipid peroxides and their products deriving from hepatocytes, Kupffer cells and other cells converge on HSC and influence their activation. This review focuses on glutathione and thioredoxin pathways, with particular emphasis on their role in HSC. These two systems have been shown to act in the metabolism of hydrogen peroxide, control of thiol redox balance and regulation of signalling pathways. Particular attention is paid to mitochondria and NADPH oxidase. Detailed knowledge of specific signalling, redox conditions and apoptotic processes will be of help in devising proper pharmacological treatments for liver fibrosis.
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Affiliation(s)
- Anna Maria Brunati
- Dipartimento di Chimica Biologica, Viale G. Colombo 3, 35121 Padova, Italy.
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37
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Ben-Ami R, Lewis RE, Leventakos K, Kontoyiannis DP. Aspergillus fumigatus inhibits angiogenesis through the production of gliotoxin and other secondary metabolites. Blood 2009; 114:5393-9. [PMID: 19843884 PMCID: PMC2925388 DOI: 10.1182/blood-2009-07-231209] [Citation(s) in RCA: 87] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2009] [Accepted: 09/22/2009] [Indexed: 11/20/2022] Open
Abstract
In susceptible hosts, angioinvasion by Aspergillus fumigatus triggers thrombosis, hypoxia, and proinflammatory cytokine release, all of which are stimuli for angiogenesis. We sought to determine whether A fumigatus directly modulates angiogenesis. A fumigatus culture filtrates profoundly inhibited the differentiation, migration, and capillary tube formation of human umbilical vein endothelial cells in vitro. To measure angiogenesis at the site of infection, we devised an in vivo Matrigel assay in cyclophosphamide-treated BALB/c mice with cutaneous invasive aspergillosis. Angiogenesis was significantly suppressed in Matrigel plugs implanted in A fumigatus-infected mice compared with plugs from uninfected control mice. The antiangiogenic effect of A fumigatus was completely abolished by deletion of the global regulator of secondary metabolism, laeA, and to a lesser extent by deletion of gliP, which controls gliotoxin production. Moreover, pure gliotoxin potently inhibited angiogenesis in vitro in a dose-dependent manner. Finally, overexpression of multiple angiogenesis mediator-encoding genes was observed in the lungs of cortisone-treated mice during early invasive aspergillosis, whereas gene expression returned rapidly to baseline levels in cyclophosphamide/cortisone-treated mice. Taken together, these results indicate that suppression of angiogenesis by A fumigatus both in vitro and in a neutropenic mouse model is mediated through secondary metabolite production.
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Affiliation(s)
- Ronen Ben-Ami
- Department of Infectious Diseases, Infection Control and Employee Health, University of Texas M. D. Anderson Cancer Center, Houston, TX, USA
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38
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Abstract
Redox dysregulation originating from metabolic alterations and dependence on mitogenic and survival signaling through reactive oxygen species represents a specific vulnerability of malignant cells that can be selectively targeted by redox chemotherapeutics. This review will present an update on drug discovery, target identification, and mechanisms of action of experimental redox chemotherapeutics with a focus on pro- and antioxidant redox modulators now in advanced phases of preclinal and clinical development. Recent research indicates that numerous oncogenes and tumor suppressor genes exert their functions in part through redox mechanisms amenable to pharmacological intervention by redox chemotherapeutics. The pleiotropic action of many redox chemotherapeutics that involves simultaneous modulation of multiple redox sensitive targets can overcome cancer cell drug resistance originating from redundancy of oncogenic signaling and rapid mutation.Moreover, some redox chemotherapeutics may function according to the concept of synthetic lethality (i.e., drug cytotoxicity is confined to cancer cells that display loss of function mutations in tumor suppressor genes or upregulation of oncogene expression). The impressive number of ongoing clinical trials that examine therapeutic performance of novel redox drugs in cancer patients demonstrates that redox chemotherapy has made the crucial transition from bench to bedside.
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Affiliation(s)
- Georg T Wondrak
- Department of Pharmacology and Toxicology, College of Pharmacy, Arizona Cancer Center, University of Arizona, Tucson, Arizona, USA
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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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