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Choi S, Kronstad JW, Jung WH. Siderophore Biosynthesis and Transport Systems in Model and Pathogenic Fungi. J Microbiol Biotechnol 2024; 34:1551-1562. [PMID: 38881181 PMCID: PMC11380514 DOI: 10.4014/jmb.2405.05020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2024] [Revised: 06/05/2024] [Accepted: 06/10/2024] [Indexed: 06/18/2024]
Abstract
Fungi employ diverse mechanisms for iron uptake to ensure proliferation and survival in iron-limited environments. Siderophores are secondary metabolite small molecules with a high affinity specifically for ferric iron; these molecules play an essential role in iron acquisition in fungi and significantly influence fungal physiology and virulence. Fungal siderophores, which are primarily hydroxamate types, are synthesized via non-ribosomal peptide synthetases (NRPS) or NRPS-independent pathways. Following synthesis, siderophores are excreted, chelate iron, and are transported into the cell by specific cell membrane transporters. In several human pathogenic fungi, siderophores are pivotal for virulence, as inhibition of their synthesis or transport significantly reduces disease in murine models of infection. This review briefly highlights siderophore biosynthesis and transport mechanisms in fungal pathogens as well the model fungi Saccharomyces cerevisiae and Schizosaccharomyces pombe. Understanding siderophore biosynthesis and transport in pathogenic fungi provides valuable insights into fungal biology and illuminates potential therapeutic targets for combating fungal infections.
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Affiliation(s)
- Sohyeong Choi
- Department of Systems Biotechnology, Chung-Ang University, Anseong 17546, Republic of Korea
| | - James W Kronstad
- Michael Smith Laboratories, Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada
| | - Won Hee Jung
- Department of Systems Biotechnology, Chung-Ang University, Anseong 17546, Republic of Korea
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2
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Caballero P, Yap A, Bromley MJ, Haas H. The Transcription Factors AcuK and AcuM Influence Siderophore Biosynthesis of Aspergillus fumigatus. J Fungi (Basel) 2024; 10:327. [PMID: 38786682 PMCID: PMC11121910 DOI: 10.3390/jof10050327] [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: 03/18/2024] [Revised: 04/25/2024] [Accepted: 04/26/2024] [Indexed: 05/25/2024] Open
Abstract
The mold Aspergillus fumigatus employs two high-affinity uptake systems, reductive iron assimilation (RIA) and siderophore-mediated iron acquisition (SIA), for the acquisition of the essential trace element iron. SIA has previously been shown to be crucial for virulence in mammalian hosts. Here, we show that a lack of AcuK or AcuM, transcription factors required for the activation of gluconeogenesis, decreases the production of both extra- and intracellular siderophores in A. fumigatus. The lack of AcuM or AcuK did not affect the expression of genes involved in RIA and SIA, suggesting that these regulators do not directly regulate iron homeostasis genes, but indirectly affect siderophore production through their influence on metabolism. Consistent with this, acetate supplementation reversed the intracellular siderophore production defect of ΔacuM and ΔacuK. Moreover, ΔacuM and ΔacuK displayed a similar growth defect under iron limitation and iron sufficiency, which suggests they have a general role in carbon metabolism apart from gluconeogenesis. In agreement with a potential role of the glyoxylate cycle in adaptation to iron starvation, transcript levels of the malate synthase-encoding acuE were found to be upregulated by iron limitation that is partially dependent on AcuK and AcuM. Together, these data demonstrate the influence of iron availability on carbon metabolism.
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Affiliation(s)
- Patricia Caballero
- Institute of Molecular Biology, Medical University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria; (P.C.); (A.Y.)
| | - Annie Yap
- Institute of Molecular Biology, Medical University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria; (P.C.); (A.Y.)
| | - Michael J. Bromley
- Manchester Fungal Infection Group, Division of Infection, Immunity, and Respiratory Medicine, The University of Manchester, Manchester M13 9PL, UK;
| | - Hubertus Haas
- Institute of Molecular Biology, Medical University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria; (P.C.); (A.Y.)
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3
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Wu PC, Choo YL, Wei SY, Yago JI, Chung KR. Contribution of Autophagy to Cellular Iron Homeostasis and Stress Adaptation in Alternaria alternata. Int J Mol Sci 2024; 25:1123. [PMID: 38256200 PMCID: PMC10816921 DOI: 10.3390/ijms25021123] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 01/04/2024] [Accepted: 01/14/2024] [Indexed: 01/24/2024] Open
Abstract
The tangerine pathotype of Alternaria alternata produces the Alternaria citri toxin (ACT), which elicits a host immune response characterized by the increase in harmful reactive oxygen species (ROS) production. ROS detoxification in A. alternata relies on the degradation of peroxisomes through autophagy and iron acquisition using siderophores. In this study, we investigated the role of autophagy in regulating siderophore and iron homeostasis in A. alternata. Our results showed that autophagy positively influences siderophore production and iron uptake. The A. alternata strains deficient in autophagy-related genes 1 and 8 (ΔAaatg1 and ΔAaatg8) could not thrive without iron, and their adaptability to high-iron environments was also reduced. Furthermore, the ability of autophagy-deficient strains to withstand ROS was compromised. Notably, autophagy deficiency significantly reduced the production of dimerumic acid (DMA), a siderophore in A. alternata, which may contribute to ROS detoxification. Compared to the wild-type strain, ΔAaatg8 was defective in cellular iron balances. We also observed iron-induced autophagy and lipid peroxidation in A. alternata. To summarize, our study indicates that autophagy and maintaining iron homeostasis are interconnected and contribute to the stress resistance and the virulence of A. alternata. These results provide new insights into the complex interplay connecting autophagy, iron metabolism, and fungal pathogenesis in A. alternata.
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Affiliation(s)
- Pei-Ching Wu
- Department of Plant Pathology, College of Agriculture and Natural Resources, National Chung Hsing University, Taichung 402202, Taiwan; (P.-C.W.); (Y.-L.C.); (S.-Y.W.)
| | - Yen-Ling Choo
- Department of Plant Pathology, College of Agriculture and Natural Resources, National Chung Hsing University, Taichung 402202, Taiwan; (P.-C.W.); (Y.-L.C.); (S.-Y.W.)
| | - Sian-Yong Wei
- Department of Plant Pathology, College of Agriculture and Natural Resources, National Chung Hsing University, Taichung 402202, Taiwan; (P.-C.W.); (Y.-L.C.); (S.-Y.W.)
| | - Jonar I. Yago
- Plant Science Department, College of Agriculture, Nueva Vizcaya State University, Bayombong 3700, Philippines;
| | - Kuang-Ren Chung
- Department of Plant Pathology, College of Agriculture and Natural Resources, National Chung Hsing University, Taichung 402202, Taiwan; (P.-C.W.); (Y.-L.C.); (S.-Y.W.)
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Potenciano da Silva KL, Moraes D, Lechner B, Lindner H, Haas H, Almeida Soares CM, Silva-Bailão MG, Bailão AM. Fonsecaea pedrosoi produces ferricrocin and can utilize different host iron sources. Fungal Biol 2023; 127:1512-1523. [PMID: 38097325 DOI: 10.1016/j.funbio.2023.07.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2023] [Revised: 07/08/2023] [Accepted: 07/10/2023] [Indexed: 12/18/2023]
Abstract
The survival of living organisms depends on iron, one of the most abundant metals in the Earth's crust. Nevertheless, this micronutrient is poorly available in our aerobic atmosphere as well as inside the mammalian host. This problem is circumvented by the expression of high affinity iron uptake machineries, including the production of siderophores, in pathogenic fungi. Here we demonstrated that F. pedrosoi, the causative agent of the neglected tropical disease chromoblastomycosis, presents gene clusters for siderophore production. In addition, ten putative siderophore transporters were identified. Those genes are upregulated under iron starvation, a condition that induces the secretion of hydroxamates, as revealed by chrome azurol S assays. RP-HPLC and mass spectrometry analysis allowed the identification of ferricrocin as an intra- and extracellular siderophore. F. pedrosoi can grow in different iron sources, including the bacterial ferrioxamine B and the host proteins ferritin, hemoglobin and holotransferrin. Of note, addition of hemoglobin, lactoferrin and holotransferrin to the growth medium of macrophages infected with F. pedrosoi enhanced significantly fungal survival. The ability to produce siderophores in iron limited conditions added to the versatility to utilize different sources of iron are strategies that certainly may contribute to fungal survival inside the host.
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Affiliation(s)
| | - Dayane Moraes
- Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Goiás, Brazil.
| | - Beatrix Lechner
- Institute of Molecular Biology/ Biocenter, Medical University of Innsbruck, Innsbruck, Austria.
| | - Herbert Lindner
- Institute of Medical Biochemistry/Biocenter, Medical University of Innsbruck, Innsbruck, Austria.
| | - Hubertus Haas
- Institute of Molecular Biology/ Biocenter, Medical University of Innsbruck, Innsbruck, Austria.
| | | | | | - Alexandre Melo Bailão
- Instituto de Ciências Biológicas, Universidade Federal de Goiás, Goiânia, Goiás, Brazil.
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Happacher I, Aguiar M, Yap A, Decristoforo C, Haas H. Fungal siderophore metabolism with a focus on Aspergillus fumigatus: impact on biotic interactions and potential translational applications. Essays Biochem 2023; 67:829-842. [PMID: 37313590 PMCID: PMC10500206 DOI: 10.1042/ebc20220252] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2023] [Revised: 05/22/2023] [Accepted: 05/26/2023] [Indexed: 06/15/2023]
Abstract
Iron is an essential trace element that is limiting in most habitats including hosts for fungal pathogens. Siderophores are iron-chelators synthesized by most fungal species for high-affinity uptake and intracellular handling of iron. Moreover, virtually all fungal species including those lacking siderophore biosynthesis appear to be able to utilize siderophores produced by other species. Siderophore biosynthesis has been shown to be crucial for virulence of several fungal pathogens infecting animals and plants revealing induction of this iron acquisition system during virulence, which offers translational potential of this fungal-specific system. The present article summarizes the current knowledge on the fungal siderophore system with a focus on Aspergillus fumigatus and its potential translational application including noninvasive diagnosis of fungal infections via urine samples, imaging of fungal infections via labeling of siderophores with radionuclides such as Gallium-68 for detection with positron emission tomography, conjugation of siderophores with fluorescent probes, and development of novel antifungal strategies.
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Affiliation(s)
- Isidor Happacher
- Institute of Molecular Biology, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Mario Aguiar
- Institute of Molecular Biology, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Annie Yap
- Institute of Molecular Biology, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria
| | - Clemens Decristoforo
- Department of Nuclear Medicine, Medical University Innsbruck, Innsbruck, Austria
| | - Hubertus Haas
- Institute of Molecular Biology, Biocenter, Medical University of Innsbruck, 6020 Innsbruck, Austria
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6
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Happacher I, Aguiar M, Alilou M, Abt B, Baltussen TJH, Decristoforo C, Melchers WJG, Haas H. The Siderophore Ferricrocin Mediates Iron Acquisition in Aspergillus fumigatus. Microbiol Spectr 2023; 11:e0049623. [PMID: 37199664 PMCID: PMC10269809 DOI: 10.1128/spectrum.00496-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2023] [Accepted: 04/28/2023] [Indexed: 05/19/2023] Open
Abstract
The opportunistic fungal pathogen Aspergillus fumigatus utilizes two high-affinity iron uptake mechanisms, termed reductive iron assimilation (RIA) and siderophore-mediated iron acquisition (SIA). The latter has been shown to be crucial for virulence of this fungus and is a target for development of novel strategies for diagnosis and treatment of fungal infections. So far, research on SIA in this mold focused mainly on the hyphal stage, revealing the importance of extracellular fusarinine-type siderophores in iron acquisition as well as of the siderophore ferricrocin in intracellular iron handling. The current study aimed to characterize iron acquisition during germination. High expression of genes involved in biosynthesis and uptake of ferricrocin in conidia and during germination, independent of iron availability, suggested a role of ferricrocin in iron acquisition during germination. In agreement, (i) bioassays indicated secretion of ferricrocin during growth on solid media during both iron sufficiency and limitation, (ii) ferricrocin was identified in the supernatant of conidia germinating in liquid media during both iron sufficiency and limitation, (iii) in contrast to mutants lacking all siderophores, mutants synthesizing ferricrocin but lacking fusarinine-type siderophores were able to grow under iron limitation in the absence of RIA, and (iv) genetic inactivation of the ferricrocin transporter Sit1 decreased germination in the absence of RIA. Taken together, this study revealed that ferricrocin has not only an intracellular role but also functions as an extracellular siderophore to support iron acquisition. The iron availability-independent ferricrocin secretion and uptake during early germination indicate developmental, rather than iron regulation. IMPORTANCE Aspergillus fumigatus is one of the most common airborne fungal pathogens for humans. Low-molecular-mass iron chelators, termed siderophores, have been shown to play a central role in iron homeostasis and, consequently, virulence of this mold. Previous studies demonstrated the crucial role of secreted fusarinine-type siderophores, such as triacetylfusarinine C, in iron acquisition, as well as of the ferrichrome-type siderophore ferricrocin in intracellular iron storage and transport. Here, we demonstrate that ferricrocin is also secreted to mediate iron acquisition during germination together with reductive iron assimilation. During early germination, ferricrocin secretion and uptake were not repressed by iron availability, indicating developmental regulation of this iron acquisition system in this growth phase.
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Affiliation(s)
- Isidor Happacher
- Institute of Molecular Biology, Biocenter, Medical University Innsbruck, Innsbruck, Austria
| | - Mario Aguiar
- Institute of Molecular Biology, Biocenter, Medical University Innsbruck, Innsbruck, Austria
| | - Mostafa Alilou
- Institute of Pharmacy, Unit of Pharmacognosy, Center for Molecular Biosciences Innsbruck, Austria
| | - Beate Abt
- Institute of Molecular Biology, Biocenter, Medical University Innsbruck, Innsbruck, Austria
| | - Tim J. H. Baltussen
- Department of Medical Microbiology, Radboud University Medical Centre, Nijmegen, The Netherlands
- Centre of Expertise in Mycology, Radboudumc/CWZ, Nijmegen, The Netherlands
| | - Clemens Decristoforo
- Department of Nuclear Medicine, Medical University Innsbruck, Innsbruck, Austria
| | - Willem J. G. Melchers
- Department of Medical Microbiology, Radboud University Medical Centre, Nijmegen, The Netherlands
- Centre of Expertise in Mycology, Radboudumc/CWZ, Nijmegen, The Netherlands
| | - Hubertus Haas
- Institute of Molecular Biology, Biocenter, Medical University Innsbruck, Innsbruck, Austria
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Mohamed NZ, Shaban L, Safan S, El-Sayed ASA. Physiological and metabolic traits of Taxol biosynthesis of endophytic fungi inhabiting plants: Plant-microbial crosstalk, and epigenetic regulators. Microbiol Res 2023; 272:127385. [PMID: 37141853 DOI: 10.1016/j.micres.2023.127385] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2022] [Revised: 04/08/2023] [Accepted: 04/09/2023] [Indexed: 05/06/2023]
Abstract
Attenuating the Taxol productivity of fungi with the subculturing and storage under axenic conditions is the challenge that halts the feasibility of fungi to be an industrial platform for Taxol production. This successive weakening of Taxol productivity by fungi could be attributed to the epigenetic down-regulation and molecular silencing of most of the gene clusters encoding Taxol biosynthetic enzymes. Thus, exploring the epigenetic regulating mechanisms controlling the molecular machinery of Taxol biosynthesis could be an alternative prospective technology to conquer the lower accessibility of Taxol by the potent fungi. The current review focuses on discussing the different molecular approaches, epigenetic regulators, transcriptional factors, metabolic manipulators, microbial communications and microbial cross-talking approaches on restoring and enhancing the Taxol biosynthetic potency of fungi to be industrial platform for Taxol production.
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Affiliation(s)
- Nabil Z Mohamed
- Enzymology and Fungal Biotechnology Lab, Botany and Microbiology Department, Faculty of Science, Zagazig University, Zagazig 44519, Egypt
| | - Lamis Shaban
- Enzymology and Fungal Biotechnology Lab, Botany and Microbiology Department, Faculty of Science, Zagazig University, Zagazig 44519, Egypt.
| | - Samia Safan
- Enzymology and Fungal Biotechnology Lab, Botany and Microbiology Department, Faculty of Science, Zagazig University, Zagazig 44519, Egypt
| | - Ashraf S A El-Sayed
- Enzymology and Fungal Biotechnology Lab, Botany and Microbiology Department, Faculty of Science, Zagazig University, Zagazig 44519, Egypt.
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Wei S, Hu C, Zhang Y, Lv Y, Zhang S, Zhai H, Hu Y. AnAzf1 acts as a positive regulator of ochratoxin A biosynthesis in Aspergillus niger. Appl Microbiol Biotechnol 2023; 107:2501-2514. [PMID: 36809388 DOI: 10.1007/s00253-023-12404-8] [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: 11/30/2022] [Revised: 01/18/2023] [Accepted: 01/20/2023] [Indexed: 02/23/2023]
Abstract
Aspergillus niger produces genotoxic and carcinogenic ochratoxin A (OTA) that severely threatens human and animal health. Transcription factor Azf1 is essential in regulating fungal cell development and primary metabolism. However, its effect and mechanism on secondary metabolism are unclear. Here, we characterized and deleted a Azf1 homolog gene, An15g00120 (AnAzf1), in A. niger, which completely blocked OTA production, and repressed the OTA cluster genes, p450, nrps, hal, and bzip at the transcriptional level. The results indicated that AnAzf1 was a positive regulator of OTA biosynthesis. Transcriptome sequencing results showed that the AnAzf1 deletion significantly upregulated antioxidant genes and downregulated oxidative phosphorylation genes. Enzymes involved in reactive oxygen species (ROS) scavenging, including catalase (CAT) and peroxidase (POD) were increased, and the corresponding ROS levels were decreased. Upregulation of genes (cat, catA, hog1, and gfd) in the MAPK pathway and downregulation of genes in iron homeostasis were associated with decreased ROS levels, linking the altered MAPK pathway and iron homeostasis to lower ROS levels caused by AnAzf1 deletion. Additionally, enzymes including complex I (NADH-ubiquinone oxidoreductase), and complex V (ATP synthase), as well as ATP levels, were significantly decreased, indicating impaired oxidative phosphorylation caused by the AnAzf1-deletion. During lower ROS levels and impaired oxidative phosphorylation, OTA was not produced in ∆AnAzf1. Together, these results strongly suggested that AnAzf1 deletion blocked OTA production in A. niger by a synergistic interference of ROS accumulation and oxidative phosphorylation. KEY POINTS: • AnAzf1 positively regulated OTA biosynthesis in A. niger. • Deletion of AnAzf1 decreased ROS levels and impaired oxidative phosphorylation. • An altered MAPK pathway and iron homeostasis were associated with lower ROS levels.
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Affiliation(s)
- Shan Wei
- College of Bioengineering, Henan University of Technology, Zhengzhou, 450001, People's Republic of China
- Henan Provincial Key Laboratory of Biological Processing and Nutritional Function of Wheat, Zhengzhou, 450001, People's Republic of China
| | - Chaojiang Hu
- College of Bioengineering, Henan University of Technology, Zhengzhou, 450001, People's Republic of China
- Henan Provincial Key Laboratory of Biological Processing and Nutritional Function of Wheat, Zhengzhou, 450001, People's Republic of China
| | - Yige Zhang
- College of Bioengineering, Henan University of Technology, Zhengzhou, 450001, People's Republic of China
- Henan Provincial Key Laboratory of Biological Processing and Nutritional Function of Wheat, Zhengzhou, 450001, People's Republic of China
| | - Yangyong Lv
- College of Bioengineering, Henan University of Technology, Zhengzhou, 450001, People's Republic of China
- Henan Provincial Key Laboratory of Biological Processing and Nutritional Function of Wheat, Zhengzhou, 450001, People's Republic of China
| | - Shuaibing Zhang
- College of Bioengineering, Henan University of Technology, Zhengzhou, 450001, People's Republic of China
- Henan Provincial Key Laboratory of Biological Processing and Nutritional Function of Wheat, Zhengzhou, 450001, People's Republic of China
| | - Huanchen Zhai
- College of Bioengineering, Henan University of Technology, Zhengzhou, 450001, People's Republic of China
- Henan Provincial Key Laboratory of Biological Processing and Nutritional Function of Wheat, Zhengzhou, 450001, People's Republic of China
| | - Yuansen Hu
- College of Bioengineering, Henan University of Technology, Zhengzhou, 450001, People's Republic of China.
- Henan Provincial Key Laboratory of Biological Processing and Nutritional Function of Wheat, Zhengzhou, 450001, People's Republic of China.
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Toopaang W, Panyawicha K, Srisuksam C, Hsu WC, Lin CC, Tanticharoen M, Yang YL, Amnuaykanjanasin A. Metabolomic Analysis Demonstrates the Impacts of Polyketide Synthases PKS14 and PKS15 on the Production of Beauvericins, Bassianolide, Enniatin A, and Ferricrocin in Entomopathogen Beauveria bassiana. Metabolites 2023; 13:metabo13030425. [PMID: 36984865 PMCID: PMC10057652 DOI: 10.3390/metabo13030425] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 03/04/2023] [Accepted: 03/09/2023] [Indexed: 03/16/2023] Open
Abstract
Beauveria bassiana is a globally distributed entomopathogenic fungus that produces various secondary metabolites to support its pathogenesis in insects. Two polyketide synthase genes, pks14 and pks15, are highly conserved in entomopathogenic fungi and are important for insect virulence. However, understanding of their mechanisms in insect pathogenicity is still limited. Here, we overexpressed these two genes in B. bassiana and compared the metabolite profiles of pks14 and pks15 overexpression strains to those of their respective knockout strains in culture and in vivo using tandem liquid chromatography-mass spectrometry (LC-MS/MS) with Global Natural Products Social Molecular Networking (GNPS). The pks14 and pks15 clusters exhibited crosstalk with biosynthetic clusters encoding insect-virulent metabolites, including beauvericins, bassianolide, enniatin A, and the intracellular siderophore ferricrocin under certain conditions. These secondary metabolites were upregulated in the pks14-overexpressing strain in culture and the pks15-overexpressing strain in vivo. These data suggest that pks14 and pks15, their proteins or their cluster components might be directly or indirectly associated with key pathways in insect pathogenesis of B. bassiana, particularly those related to secondary metabolism. Information about interactions between the polyketide clusters and other biosynthetic clusters improves scientific understanding about crosstalk among biosynthetic pathways and mechanisms of pathogenesis.
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Affiliation(s)
- Wachiraporn Toopaang
- National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), 113 Thailand Science Park, Paholyothin Rd., Khlong Nueng, Khlong Luang, Pathum Thani 12120, Thailand
- Molecular and Biological Agricultural Sciences, Taiwan International Graduate Program, Academia Sinica and National Chung Hsing University, Taiwan
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei 11529, Taiwan
| | - Kullyanee Panyawicha
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei 11529, Taiwan
- Institute of Biotechnology, College of Bioresources and Agriculture, National Taiwan University, Taipei 10617, Taiwan
| | - Chettida Srisuksam
- National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), 113 Thailand Science Park, Paholyothin Rd., Khlong Nueng, Khlong Luang, Pathum Thani 12120, Thailand
| | - Wei-Chen Hsu
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei 11529, Taiwan
- Biotechnology Center in Southern Taiwan, Academia Sinica, Tainan 711010, Taiwan
| | - Ching-Chih Lin
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei 11529, Taiwan
- Biotechnology Center in Southern Taiwan, Academia Sinica, Tainan 711010, Taiwan
| | - Morakot Tanticharoen
- School of Bioresources and Technology, King Mongkut’s University of Technology Thonburi, Bangkok 10140, Thailand
| | - Yu-Liang Yang
- Agricultural Biotechnology Research Center, Academia Sinica, Taipei 11529, Taiwan
- Biotechnology Center in Southern Taiwan, Academia Sinica, Tainan 711010, Taiwan
- Correspondence: (Y.-L.Y.); (A.A.)
| | - Alongkorn Amnuaykanjanasin
- National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), 113 Thailand Science Park, Paholyothin Rd., Khlong Nueng, Khlong Luang, Pathum Thani 12120, Thailand
- Correspondence: (Y.-L.Y.); (A.A.)
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The Role of the Yersiniachelin Siderophore in the Physiology of <i>Yersinia pestis</i>. PROBLEMS OF PARTICULARLY DANGEROUS INFECTIONS 2023. [DOI: 10.21055/0370-1069-2022-4-75-81] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Pathogenic bacteria use low-molecular-weight iron chelators – siderophores – to assimilate iron in the host body. Being recognized as virulence factors, these molecules, differing in structural and functional properties, are the subject of the most intensive research in medical microbiology. The present study is devoted to the investigation of yersiniachelin siderophore (Ych) found in the causative agent of plague, Yersinia pestis. The aim of the work was to clarify the role of Ych in the physiology of Y. pestis by comparing the properties of three strains of the plague microbe, differing in Ych production. Materials and methods. Three variants of Y. pestis EV76 strain were used in the experiments: parent strain Y. pestis EV76, its mutant that does not produce Ych due to deletion of three siderophore biosynthesis genes (analogues of ypo1530–1532 in Y. pestis CO92 strain) and a complemented mutant that was transformed by a recombinant pSC-A-5EV plasmid containing Ych biosynthesis genes cloned into the high-copy plasmid vector pSC-A-amp/kan. Comparative analysis of the three strains was carried out in terms of colony morphology, siderophore activity, growth rate, and sensitivity to hydrogen peroxide. Results and discussion. The comparison of these strains has revealed that the secretion of Ych by bacteria at 26 °С ensures the assimilation of iron. At 37 °С, Ych is not secreted into the medium and protects bacteria from the bactericidal action of reactive oxygen compounds. Thus, the study shows that yersiniachelin is able to stimulate the assimilation of iron by bacteria under iron-deficit conditions and has antioxidant properties.
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Li H, Dai J, Shi Y, Zhu X, Jia L, Yang Z. Molecular Regulatory Mechanism of the Iron-Ion-Promoted Asexual Sporulation of Antrodia cinnamomea in Submerged Fermentation Revealed by Comparative Transcriptomics. J Fungi (Basel) 2023; 9:jof9020235. [PMID: 36836349 PMCID: PMC9959139 DOI: 10.3390/jof9020235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 01/29/2023] [Accepted: 02/08/2023] [Indexed: 02/12/2023] Open
Abstract
Antrodia cinnamomea is a precious edible and medicinal fungus with activities of antitumor, antivirus, and immunoregulation. Fe2+ was found to promote the asexual sporulation of A. cinnamomea markedly, but the molecular regulatory mechanism of the effect is unclear. In the present study, comparative transcriptomics analysis using RNA sequencing (RNA-seq) and real time quantitative PCR (RT-qPCR) were conducted on A. cinnamomea mycelia cultured in the presence or absence of Fe2+ to reveal the molecular regulatory mechanisms underlying iron-ion-promoted asexual sporulation. The obtained mechanism is as follows: A. cinnamomea acquires iron ions through reductive iron assimilation (RIA) and siderophore-mediated iron assimilation (SIA). In RIA, ferrous iron ions are directly transported into cells by the high-affinity protein complex formed by a ferroxidase (FetC) and an Fe transporter permease (FtrA). In SIA, siderophores are secreted externally to chelate the iron in the extracellular environment. Then, the chelates are transported into cells through the siderophore channels (Sit1/MirB) on the cell membrane and hydrolyzed by a hydrolase (EstB) in the cell to release iron ions. The O-methyltransferase TpcA and the regulatory protein URBS1 promote the synthesis of siderophores. HapX and SreA respond to and maintain the balance of the intercellular concentration of iron ions. Furthermore, HapX and SreA promote the expression of flbD and abaA, respectively. In addition, iron ions promote the expression of relevant genes in the cell wall integrity signaling pathway, thereby accelerating the cell wall synthesis and maturation of spores. This study contributes to the rational adjustment and control of the sporulation of A. cinnamomea and thereby improves the efficiency of the preparation of inoculum for submerged fermentation.
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Affiliation(s)
- Huaxiang Li
- College of Food Science and Engineering, Yangzhou University, Yangzhou 225009, China
| | - Jianing Dai
- College of Food Science and Engineering, Yangzhou University, Yangzhou 225009, China
| | - Yu Shi
- College of Food Science and Engineering, Yangzhou University, Yangzhou 225009, China
| | - Xiaoyan Zhu
- Jiangsu Provincial Key Construction Laboratory of Probiotics Preparation, Huaiyin Institute of Technology, Huaian 223003, China
| | - Luqiang Jia
- College of Food Science and Engineering, Yangzhou University, Yangzhou 225009, China
| | - Zhenquan Yang
- College of Food Science and Engineering, Yangzhou University, Yangzhou 225009, China
- Jiangsu Key Laboratory of Dairy Biotechnology and Safety Control, Yangzhou University, Yangzhou 225009, China
- Correspondence:
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12
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Schüller A, Studt-Reinhold L, Strauss J. How to Completely Squeeze a Fungus-Advanced Genome Mining Tools for Novel Bioactive Substances. Pharmaceutics 2022; 14:1837. [PMID: 36145585 PMCID: PMC9505985 DOI: 10.3390/pharmaceutics14091837] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 08/23/2022] [Accepted: 08/29/2022] [Indexed: 11/17/2022] Open
Abstract
Fungal species have the capability of producing an overwhelming diversity of bioactive substances that can have beneficial but also detrimental effects on human health. These so-called secondary metabolites naturally serve as antimicrobial "weapon systems", signaling molecules or developmental effectors for fungi and hence are produced only under very specific environmental conditions or stages in their life cycle. However, as these complex conditions are difficult or even impossible to mimic in laboratory settings, only a small fraction of the true chemical diversity of fungi is known so far. This also implies that a large space for potentially new pharmaceuticals remains unexplored. We here present an overview on current developments in advanced methods that can be used to explore this chemical space. We focus on genetic and genomic methods, how to detect genes that harbor the blueprints for the production of these compounds (i.e., biosynthetic gene clusters, BGCs), and ways to activate these silent chromosomal regions. We provide an in-depth view of the chromatin-level regulation of BGCs and of the potential to use the CRISPR/Cas technology as an activation tool.
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Affiliation(s)
| | | | - Joseph Strauss
- Institute of Microbial Genetics, Department of Applied Genetics and Cell Biology, University of Natural Resources and Life Sciences Vienna, A-3430 Tulln/Donau, Austria
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13
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Ye J, Wang Y, Li X, Wan Q, Zhang Y, Lu L. Synergistic Antifungal Effect of a Combination of Iron Deficiency and Calcium Supplementation. Microbiol Spectr 2022; 10:e0112122. [PMID: 35674440 PMCID: PMC9241635 DOI: 10.1128/spectrum.01121-22] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Accepted: 05/19/2022] [Indexed: 01/10/2023] Open
Abstract
Fungal diseases have become a major public health issue worldwide. Increasing drug resistance and the limited number of available antifungals result in high morbidity and mortality. Metal-based drugs have been reported to be therapeutic agents against major protozoan diseases, but knowledge of their ability to function as antifungals is limited. In this study, we found that calcium supplementation combined with iron deficiency causes dramatic growth inhibition of the human fungal pathogens Aspergillus fumigatus, Candida albicans, and Cryptococcus neoformans. Calcium induces the downregulation of iron uptake-related genes and, in particular, causes a decrease in the expression of the transcription factor HapX, which tends to transcriptionally activate siderophore-mediated iron acquisition under iron-deficient conditions. Iron deficiency causes calcium overload and the overproduction of intracellular reactive oxygen species (ROS), and perturbed ion homeostasis suppresses fungal growth. These phenomena are consistently identified in azole-resistant A. fumigatus isolates. The findings here imply that low iron availability lets cells mistakenly absorb calcium as a substitute, causing calcium abnormalities. Thus, there is a mutual effect between iron and calcium in fungal pathogens, and the combination of calcium with an iron chelator could serve to improve antifungal therapy. IMPORTANCE Millions of immunocompromised people are at a higher risk of developing different types of severe fungal diseases. The limited number of antifungals and the emergence of antimicrobial resistance highlight an urgent need for new strategies against invasive fungal infections. Here, we report that calcium can interfere with iron absorption of fungal pathogens, especially in iron-limited environments. Thus, a combination of calcium supplementation with an iron chelator inhibits the growth of human fungal pathogens, including Aspergillus fumigatus, Candida albicans, and Cryptococcus neoformans. Moreover, we demonstrate that iron deficiency induces a nonspecific calcium uptake response, which results in toxic levels of metal. Findings in this study suggest that a microenvironment with excess calcium and limited iron is an efficient strategy to curb the growth of fungal pathogens, especially for drug-resistant isolates.
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Affiliation(s)
- Jing Ye
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Centre for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Yamei Wang
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Centre for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Xinyu Li
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Centre for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Qinyi Wan
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Centre for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Yuanwei Zhang
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Centre for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing, China
| | - Ling Lu
- Jiangsu Key Laboratory for Microbes and Functional Genomics, Jiangsu Engineering and Technology Research Centre for Microbiology, College of Life Sciences, Nanjing Normal University, Nanjing, China
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14
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Michels K, Solomon AL, Scindia Y, Sordo Vieira L, Goddard Y, Whitten S, Vaulont S, Burdick MD, Atkinson C, Laubenbacher R, Mehrad B. Aspergillus Utilizes Extracellular Heme as an Iron Source During Invasive Pneumonia, Driving Infection Severity. J Infect Dis 2022; 225:1811-1821. [PMID: 35267014 PMCID: PMC9113461 DOI: 10.1093/infdis/jiac079] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 03/01/2022] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Depriving microbes of iron is critical to host defense. Hemeproteins, the largest source of iron within vertebrates, are abundant in infected tissues in aspergillosis due to hemorrhage, but Aspergillus species have been thought to lack heme import mechanisms. We hypothesized that heme provides iron to Aspergillus during invasive pneumonia, thereby worsening the outcomes of the infection. METHODS We assessed the effect of heme on fungal phenotype in various in vitro conditions and in a neutropenic mouse model of invasive pulmonary aspergillosis. RESULTS In mice with neutropenic invasive aspergillosis, we found a progressive and compartmentalized increase in lung heme iron. Fungal cells cultured under low iron conditions took up heme, resulting in increased fungal iron content, resolution of iron starvation, increased conidiation, and enhanced resistance to oxidative stress. Intrapulmonary administration of heme to mice with neutropenic invasive aspergillosis resulted in markedly increased lung fungal burden, lung injury, and mortality, whereas administration of heme analogs or heme with killed Aspergillus did not. Finally, infection caused by fungal germlings cultured in the presence of heme resulted in a more severe infection. CONCLUSIONS Invasive aspergillosis induces local hemolysis in infected tissues, thereby supplying heme iron to the fungus, leading to lethal infection.
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Affiliation(s)
- Kathryn Michels
- Department of Microbiology, Immunology and Cancer Biology, University of Virginia, Charlottesville, Virginia, USA
| | - Angelica L Solomon
- Division of Pulmonary, Critical Care, and Sleep Medicine, University of Florida, Gainesville, Florida, USA
| | - Yogesh Scindia
- Division of Pulmonary, Critical Care, and Sleep Medicine, University of Florida, Gainesville, Florida, USA
| | - Luis Sordo Vieira
- Division of Pulmonary, Critical Care, and Sleep Medicine, University of Florida, Gainesville, Florida, USA
| | - Yana Goddard
- Division of Pulmonary, Critical Care, and Sleep Medicine, University of Florida, Gainesville, Florida, USA
| | - Spencer Whitten
- Division of Pulmonary, Critical Care, and Sleep Medicine, University of Florida, Gainesville, Florida, USA
| | - Sophie Vaulont
- Université de Paris, INSERM U1016, Institut Cochin, Paris, France
| | - Marie D Burdick
- Division of Pulmonary, Critical Care, and Sleep Medicine, University of Florida, Gainesville, Florida, USA
| | - Carl Atkinson
- Division of Pulmonary, Critical Care, and Sleep Medicine, University of Florida, Gainesville, Florida, USA
| | - Reinhard Laubenbacher
- Division of Pulmonary, Critical Care, and Sleep Medicine, University of Florida, Gainesville, Florida, USA
| | - Borna Mehrad
- Division of Pulmonary, Critical Care, and Sleep Medicine, University of Florida, Gainesville, Florida, USA
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15
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Asai Y, Hiratsuka T, Ueda M, Kawamura Y, Asamizu S, Onaka H, Arioka M, Nishimura S, Yoshida M. Differential Biosynthesis and Roles of Two Ferrichrome-Type Siderophores, ASP2397/AS2488053 and Ferricrocin, in Acremonium persicinum. ACS Chem Biol 2022; 17:207-216. [PMID: 35000376 DOI: 10.1021/acschembio.1c00867] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Ferrichromes are a family of fungal siderophores with cyclic hexapeptide structures. Most fungi produce one or two ferrichrome-type siderophores. Acremonium persicinum MF-347833 produces ferrichrome-like potent Trojan horse antifungal antibiotics ASP2397 and AS2488053, the aluminum- and iron-chelating forms of AS2488059, respectively. Here, we show by gene sequencing followed by gene deletion experiments that A. persicinum MF-347833 possesses two nonribosomal peptide synthetase genes responsible for AS2488059 and ferricrocin assembly. AS2488059 was produced under iron starvation conditions and excreted into the media to serve as a defense metabolite and probably an iron courier. In contrast, ferricrocin was produced under iron-replete conditions and retained inside the cells, likely serving as an iron-sequestering molecule. Notably, the phylogenetic analyses suggest the different evolutionary origin of AS2488059 from that of conventional ferrichrome-type siderophores. Harnessing two ferrichrome-type siderophores with distinct biological properties may give A. persicinum a competitive advantage for surviving the natural environment.
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Affiliation(s)
- Yoshiki Asai
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Tomoshige Hiratsuka
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
- RIKEN Center for Sustainable Resource Science, Wako, Saitama 351-0198, Japan
| | - Miyu Ueda
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Yumi Kawamura
- RIKEN Center for Sustainable Resource Science, Wako, Saitama 351-0198, Japan
| | - Shumpei Asamizu
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
- Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Hiroyasu Onaka
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
- Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Manabu Arioka
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
- Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Shinichi Nishimura
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
- Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
| | - Minoru Yoshida
- Department of Biotechnology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
- RIKEN Center for Sustainable Resource Science, Wako, Saitama 351-0198, Japan
- Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
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16
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Gerke J, Köhler AM, Wennrich JP, Große V, Shao L, Heinrich AK, Bode HB, Chen W, Surup F, Braus GH. Biosynthesis of Antibacterial Iron-Chelating Tropolones in Aspergillus nidulans as Response to Glycopeptide-Producing Streptomycetes. FRONTIERS IN FUNGAL BIOLOGY 2022; 2:777474. [PMID: 37744088 PMCID: PMC10512232 DOI: 10.3389/ffunb.2021.777474] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/15/2021] [Accepted: 12/06/2021] [Indexed: 09/26/2023]
Abstract
The soil microbiome comprises numerous filamentous fungi and bacteria that mutually react and challenge each other by the production of bioactive secondary metabolites. Herein, we show in liquid co-cultures that the presence of filamentous Streptomycetes producing antifungal glycopeptide antibiotics induces the production of the antibacterial and iron-chelating tropolones anhydrosepedonin (1) and antibiotic C (2) in the mold Aspergillus nidulans. Additionally, the biosynthesis of the related polyketide tripyrnidone (5) was induced, whose novel tricyclic scaffold we elucidated by NMR and HRESIMS data. The corresponding biosynthetic polyketide synthase-encoding gene cluster responsible for the production of these compounds was identified. The tropolones as well as tripyrnidone (5) are produced by genes that belong to the broad reservoir of the fungal genome for the synthesis of different secondary metabolites, which are usually silenced under standard laboratory conditions. These molecules might be part of the bacterium-fungus competition in the complex soil environment, with the bacterial glycopeptide antibiotic as specific environmental trigger for fungal induction of this cluster.
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Affiliation(s)
- Jennifer Gerke
- Department of Moleuclar Microbiology and Genetics and Göttingen Center for Molecular Biosciences (GZMB), Georg-August-Universität Göttingen, Göttingen, Germany
| | - Anna M. Köhler
- Department of Moleuclar Microbiology and Genetics and Göttingen Center for Molecular Biosciences (GZMB), Georg-August-Universität Göttingen, Göttingen, Germany
| | - Jan-Peer Wennrich
- Microbial Drugs Department, Helmholtz Centre for Infection Research (HZI), Braunschweig, Germany
- German Centre for Infection Research (DZIF), Partner Site Hannover-Braunschweig, Braunschweig, Germany
| | - Verena Große
- Department of Moleuclar Microbiology and Genetics and Göttingen Center for Molecular Biosciences (GZMB), Georg-August-Universität Göttingen, Göttingen, Germany
| | - Lulu Shao
- Microbial Drugs Department, Helmholtz Centre for Infection Research (HZI), Braunschweig, Germany
- German Centre for Infection Research (DZIF), Partner Site Hannover-Braunschweig, Braunschweig, Germany
| | - Antje K. Heinrich
- Molecular Biotechnology, Goethe University Frankfurt, Frankfurt am Main, Germany
| | - Helge B. Bode
- Molecular Biotechnology, Goethe University Frankfurt, Frankfurt am Main, Germany
- Department of Natural Products in Organismic Interactions, Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
| | - Wanping Chen
- Department of Moleuclar Microbiology and Genetics and Göttingen Center for Molecular Biosciences (GZMB), Georg-August-Universität Göttingen, Göttingen, Germany
| | - Frank Surup
- Microbial Drugs Department, Helmholtz Centre for Infection Research (HZI), Braunschweig, Germany
- German Centre for Infection Research (DZIF), Partner Site Hannover-Braunschweig, Braunschweig, Germany
| | - Gerhard H. Braus
- Department of Moleuclar Microbiology and Genetics and Göttingen Center for Molecular Biosciences (GZMB), Georg-August-Universität Göttingen, Göttingen, Germany
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17
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Iron homeostasis in the absence of ferricrocin and its consequences in fungal development and insect virulence in Beauveria bassiana. Sci Rep 2021; 11:19624. [PMID: 34608174 PMCID: PMC8490459 DOI: 10.1038/s41598-021-99030-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2021] [Accepted: 09/14/2021] [Indexed: 11/28/2022] Open
Abstract
The putative ferricrocin synthetase gene ferS in the fungal entomopathogen Beauveria bassiana BCC 2660 was identified and characterized. The 14,445-bp ferS encodes a multimodular nonribosomal siderophore synthetase tightly clustered with Fusarium graminearum ferricrocin synthetase. Functional analysis of this gene was performed by disruption with the bar cassette. ΔferS mutants were verified by Southern and PCR analyses. HPLC and TLC analyses of crude extracts indicated that biosynthesis of ferricrocin was abolished in ΔferS. Insect bioassays surprisingly indicated that ΔferS killed the Spodoptera exigua larvae faster (LT50 59 h) than wild type (66 h). Growth and developmental assays of the mutant and wild type demonstrated that ΔferS had a significant increase in germination under iron depletion and radial growth and a decrease in conidiation. Mitotracker staining showed that the mitochondrial activity was enriched in ΔferS under both iron excess and iron depletion. Comparative transcriptomes between wild type and ΔferS indicated that the mutant was increased in the expression of eight cytochrome P450 genes and those in iron homeostasis, ferroptosis, oxidative stress response, ergosterol biosynthesis, and TCA cycle, compared to wild type. Our data suggested that ΔferS sensed the iron excess and the oxidative stress and, in turn, was up-regulated in the antioxidant-related genes and those in ergosterol biosynthesis and TCA cycle. These increased biological pathways help ΔferS grow and germinate faster than the wild type and caused higher insect mortality than the wild type in the early phase of infection.
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18
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Davolos D, Russo F, Canfora L, Malusà E, Tartanus M, Furmanczyk EM, Ceci A, Maggi O, Persiani AM. A Genomic and Transcriptomic Study on the DDT-Resistant Trichoderma hamatum FBL 587: First Genetic Data into Mycoremediation Strategies for DDT-Polluted Sites. Microorganisms 2021; 9:microorganisms9081680. [PMID: 34442757 PMCID: PMC8401308 DOI: 10.3390/microorganisms9081680] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2021] [Revised: 08/01/2021] [Accepted: 08/04/2021] [Indexed: 01/09/2023] Open
Abstract
Trichoderma hamatum FBL 587 isolated from DDT-contaminated agricultural soils stands out as a remarkable strain with DDT-resistance and the ability to enhance DDT degradation process in soil. Here, whole genome sequencing and RNA-Seq studies for T. hamatum FBL 587 under exposure to DDT were performed. In the 38.9 Mb-genome of T. hamatum FBL 587, 10,944 protein-coding genes were predicted and annotated, including those of relevance to mycoremediation such as production of secondary metabolites and siderophores. The genome-scale transcriptional responses of T. hamatum FBL 587 to DDT exposure showed 1706 upregulated genes, some of which were putatively involved in the cellular translocation and degradation of DDT. With regards to DDT removal capacity, it was found upregulation of metabolizing enzymes such as P450s, and potentially of downstream DDT-transforming enzymes such as epoxide hydrolases, FAD-dependent monooxygenases, glycosyl- and glutathione-transferases. Based on transcriptional responses, the DDT degradation pathway could include transmembrane transporters of DDT, antioxidant enzymes for oxidative stress due to DDT exposure, as well as lipases and biosurfactants for the enhanced solubility of DDT. Our study provides the first genomic and transcriptomic data on T. hamatum FBL 587 under exposure to DDT, which are a base for a better understanding of mycoremediation strategies for DDT-polluted sites.
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Affiliation(s)
- Domenico Davolos
- Department of Technological Innovations and Safety of Plants, Products and Anthropic Settlements (DIT), INAIL, Research Area, Via R. Ferruzzi 38/40, 00143 Rome, Italy
- Correspondence: ; Tel.: +39-0654876328
| | - Fabiana Russo
- Department of Environmental Biology, Sapienza University of Rome, P.le A. Moro 5, 00185 Rome, Italy; (F.R.); (A.C.); (O.M.); (A.M.P.)
| | - Loredana Canfora
- Council of Agricultural Research and Economics, Centre for Agriculture and Environment, Via Della Navicella 2/4, 00184 Rome, Italy;
| | - Eligio Malusà
- The National Institute of Horticultural Research, ul. Konstytucji 3 Maja 1/3, 96-100 Skierniewice, Poland; (E.M.); (M.T.); (E.M.F.)
| | - Małgorzata Tartanus
- The National Institute of Horticultural Research, ul. Konstytucji 3 Maja 1/3, 96-100 Skierniewice, Poland; (E.M.); (M.T.); (E.M.F.)
| | - Ewa Maria Furmanczyk
- The National Institute of Horticultural Research, ul. Konstytucji 3 Maja 1/3, 96-100 Skierniewice, Poland; (E.M.); (M.T.); (E.M.F.)
| | - Andrea Ceci
- Department of Environmental Biology, Sapienza University of Rome, P.le A. Moro 5, 00185 Rome, Italy; (F.R.); (A.C.); (O.M.); (A.M.P.)
| | - Oriana Maggi
- Department of Environmental Biology, Sapienza University of Rome, P.le A. Moro 5, 00185 Rome, Italy; (F.R.); (A.C.); (O.M.); (A.M.P.)
| | - Anna Maria Persiani
- Department of Environmental Biology, Sapienza University of Rome, P.le A. Moro 5, 00185 Rome, Italy; (F.R.); (A.C.); (O.M.); (A.M.P.)
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19
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Ashraf S, Dhusia K, Verma S. Siderophores Mediated Iron Acquisition and Virulence of Brown Rot Disease in Stone Fruits Caused by Monilinia fructicola in Jammu and Kashmir. Fungal Biol 2021. [DOI: 10.1007/978-3-030-53077-8_4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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20
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Misslinger M, Hortschansky P, Brakhage AA, Haas H. Fungal iron homeostasis with a focus on Aspergillus fumigatus. BIOCHIMICA ET BIOPHYSICA ACTA-MOLECULAR CELL RESEARCH 2020; 1868:118885. [PMID: 33045305 DOI: 10.1016/j.bbamcr.2020.118885] [Citation(s) in RCA: 64] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 09/15/2020] [Accepted: 10/01/2020] [Indexed: 02/08/2023]
Abstract
To maintain iron homeostasis, fungi have to balance iron acquisition, storage, and utilization to ensure sufficient supply and to avoid toxic excess of this essential trace element. As pathogens usually encounter iron limitation in the host niche, this metal plays a particular role during virulence. Siderophores are iron-chelators synthesized by most, but not all fungal species to sequester iron extra- and intracellularly. In recent years, the facultative human pathogen Aspergillus fumigatus has become a model for fungal iron homeostasis of siderophore-producing fungal species. This article summarizes the knowledge on fungal iron homeostasis and its links to virulence with a focus on A. fumigatus. It covers mechanisms for iron acquisition, storage, and detoxification, as well as the modes of transcriptional iron regulation and iron sensing in A. fumigatus in comparison to other fungal species. Moreover, potential translational applications of the peculiarities of fungal iron metabolism for treatment and diagnosis of fungal infections is addressed.
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Affiliation(s)
- Matthias Misslinger
- Institute of Molecular Biology - Biocenter, Medical University of Innsbruck, Innsbruck, Austria
| | - Peter Hortschansky
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology-Hans Knöll Institute (HKI), Jena, Germany
| | - Axel A Brakhage
- Department of Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology-Hans Knöll Institute (HKI), Jena, Germany; Department Microbiology and Molecular Biology, Institute of Microbiology, Friedrich Schiller University Jena, Jena, Germany
| | - Hubertus Haas
- Institute of Molecular Biology - Biocenter, Medical University of Innsbruck, Innsbruck, Austria.
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21
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Nairz M, Weiss G. Iron in infection and immunity. Mol Aspects Med 2020; 75:100864. [PMID: 32461004 DOI: 10.1016/j.mam.2020.100864] [Citation(s) in RCA: 163] [Impact Index Per Article: 40.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2020] [Revised: 04/25/2020] [Accepted: 05/05/2020] [Indexed: 12/12/2022]
Abstract
Iron is an essential micronutrient for virtually all living cells. In infectious diseases, both invading pathogens and mammalian cells including those of the immune system require iron to sustain their function, metabolism and proliferation. On the one hand, microbial iron uptake is linked to the virulence of most human pathogens. On the other hand, the sequestration of iron from bacteria and other microorganisms is an efficient strategy of host defense in line with the principles of 'nutritional immunity'. In an acute infection, host-driven iron withdrawal inhibits the growth of pathogens. Chronic immune activation due to persistent infection, autoimmune disease or malignancy however, sequesters iron not only from infectious agents, autoreactive lymphocytes and neoplastic cells but also from erythroid progenitors. This is one of the key mechanisms which collectively result in the anemia of chronic inflammation. In this review, we highlight the most important interconnections between iron metabolism and immunity, focusing on host defense against relevant infections and on the clinical consequences of anemia of inflammation.
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Affiliation(s)
- Manfred Nairz
- Department of Internal Medicine II, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Austria
| | - Günter Weiss
- Department of Internal Medicine II, Infectious Diseases, Immunology, Rheumatology, Pneumology, Medical University of Innsbruck, Austria; Christian Doppler Laboratory for Iron Metabolism and Anemia Research, Medical University of Innsbruck, Austria.
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23
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Alternaria alternata uses two siderophore systems for iron acquisition. Sci Rep 2020; 10:3587. [PMID: 32107432 PMCID: PMC7046739 DOI: 10.1038/s41598-020-60468-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2019] [Accepted: 02/10/2020] [Indexed: 01/21/2023] Open
Abstract
Iron is one of the most abundant elements on earth and essential for life. However, Fe3+ ions are rather insoluble and microorganisms such as fungi may use siderophores as strong chelators for uptake. In addition, free cytoplasmic iron is rather toxic and intracellular siderophores are used to control the toxicity. Siderophores are also important for iron storage. We studied two siderophore systems in the plant necrotrophic fungus Alternaria alternata and show that the non-ribosomal peptide synthase, Nps2, is required for the biosynthesis of intracellular ferricrocin, whereas Nps6 is needed for the formation of extracellular coprogen and coprogen B. Whereas nps2 was dispensable for growth on iron-depleted medium, nps6 was essential under those conditions. nps2 deletion caused an increase in spore formation and reduced pathogenicity on tomato. Our results suggest that A. alternata employs an external and an internal siderophore system to adapt to low iron conditions.
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24
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Spore Germination Requires Ferrichrome Biosynthesis and the Siderophore Transporter Str1 in Schizosaccharomyces pombe. Genetics 2019; 211:893-911. [PMID: 30647069 DOI: 10.1534/genetics.118.301843] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 01/14/2019] [Indexed: 01/29/2023] Open
Abstract
Spore germination is a process whereby spores exit dormancy to become competent for mitotic cell division. In Schizosaccharomyces pombe, one critical step of germination is the formation of a germ tube that hatches out the spore wall in a stage called outgrowth. Here, we show that iron deficiency blocks the outgrowth of germinating spores. The siderophore synthetase Sib1 and the ornithine N5-oxygenase Sib2 participate in ferrichrome biosynthesis, whereas Str1 functions as a ferrichrome transporter. Expression profiles of sib1+ , sib2+ , and str1+ transcripts reveal that they are induced shortly after induction of germination and their expression remains upregulated throughout the germination program under low-iron conditions. sib1Δ sib2Δ mutant spores are unable to form a germ tube under iron-poor conditions. Supplementation with exogenous ferrichrome suppresses this phenotype when str1+ is present. Str1 localizes at the contour of swollen spores 4 hr after induction of germination. At the onset of outgrowth, localization of Str1 changes and it moves away from the mother spore to primarily localize at the periphery of the new daughter cell. Two conserved Tyr residues (Tyr553 and Tyr567) are predicted to be located in the last extracellular loop region of Str1. Results show that these amino acid residues are critical to ensure timely completion of the outgrowth phase of spores in response to exogenous ferrichrome. Taken together, the results reveal the essential requirement of ferrichrome biosynthesis to promote outgrowth, as well as the necessity to take up ferrichrome from an external source via Str1 when ferrichrome biosynthesis is blocked.
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25
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Chelius CL, Ribeiro LFC, Huso W, Kumar J, Lincoln S, Tran B, Goo YA, Srivastava R, Harris SD, Marten MR. Phosphoproteomic and transcriptomic analyses reveal multiple functions for Aspergillus nidulans MpkA independent of cell wall stress. Fungal Genet Biol 2019; 125:1-12. [PMID: 30639305 DOI: 10.1016/j.fgb.2019.01.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2018] [Revised: 12/18/2018] [Accepted: 01/04/2019] [Indexed: 12/17/2022]
Abstract
The protein kinase MpkA plays a prominent role in the cell wall integrity signaling (CWIS) pathway, acting as the terminal MAPK activating expression of genes which encode cell wall biosynthetic enzymes and other repair functions. Numerous studies focus on MpkA function during cell wall perturbation. Here, we focus on the role MpkA plays outside of cell wall stress, during steady state growth. In an effort to seek other, as yet unknown, connections to this pathway, an mpkA deletion mutant (ΔmpkA) was subjected to phosphoproteomic and transcriptomic analysis. When compared to the control (isogenic parent of ΔmpkA), there is strong evidence suggesting MpkA is involved with maintaining cell wall strength, branching regulation, and the iron starvation pathway, among others. Particle-size analysis during shake flask growth revealed ΔmpkA mycelia were about 4 times smaller than the control strain and more than 90 cell wall related genes show significantly altered expression levels. The deletion mutant had a significantly higher branching rate than the control and phosphoproteomic results show putative branching-regulation proteins, such as CotA, LagA, and Cdc24, have a significantly different level of phosphorylation. When grown in iron limited conditions, ΔmpkA had no difference in growth rate or production of siderophores, whereas the control strain showed decreased growth rate and increased siderophore production. Transcriptomic data revealed over 25 iron related genes with altered transcript levels. Results suggest MpkA is involved with regulation of broad cellular functions in the absence of stress.
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Affiliation(s)
- Cynthia L Chelius
- Department of Chemical, Biochemical, and Environmental Engineering, University of Maryland Baltimore County, Baltimore, MD 21250, United States
| | - Liliane F C Ribeiro
- Department of Chemical, Biochemical, and Environmental Engineering, University of Maryland Baltimore County, Baltimore, MD 21250, United States
| | - Walker Huso
- Department of Chemical, Biochemical, and Environmental Engineering, University of Maryland Baltimore County, Baltimore, MD 21250, United States
| | - Jyothi Kumar
- Center for Plant Science Innovation and Department of Plant Pathology, University of Nebraska-Lincoln, Lincoln, NE 68588, United States
| | - Stephen Lincoln
- Department of Chemical and Biomolecular Engineering, University of Connecticut, Storrs, CT 06269, United States
| | - Bao Tran
- Mass Spectrometry Center, University of Maryland School of Pharmacy, Baltimore, MD, 21201, United States
| | - Young Ah Goo
- Mass Spectrometry Center, University of Maryland School of Pharmacy, Baltimore, MD, 21201, United States
| | - Ranjan Srivastava
- Department of Chemical and Biomolecular Engineering, University of Connecticut, Storrs, CT 06269, United States
| | - Steven D Harris
- Center for Plant Science Innovation and Department of Plant Pathology, University of Nebraska-Lincoln, Lincoln, NE 68588, United States
| | - Mark R Marten
- Department of Chemical, Biochemical, and Environmental Engineering, University of Maryland Baltimore County, Baltimore, MD 21250, United States.
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26
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Albelda-Berenguer M, Monachon M, Joseph E. Siderophores: From natural roles to potential applications. ADVANCES IN APPLIED MICROBIOLOGY 2019; 106:193-225. [PMID: 30798803 DOI: 10.1016/bs.aambs.2018.12.001] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Siderophores are secondary metabolites produced by different organisms in order to scavenge iron from their surrounding environment making this essential element available to the cell. Presenting high affinity for ferric iron, siderophores are secreted out to form soluble ferric complexes that can be taken up by the organisms. Siderophores present complex chemistry that allows them to form the strongest iron-chelating complexes. Interest in this field is always up to date and new siderophores are found with new roles and applications. For example, siderophores participate to the mobilization of iron and other elements and are involved in virulence processes. Recently, a strong relation between siderophores and oxidative stress tolerance has been also highlighted. Their application in medicine has been widely studied as well as in agriculture. However, new fields are paying attention to the use of siderophores as green-iron chelators. In particular, siderophores have been proposed for the preservation of cultural heritage.
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Affiliation(s)
- Magdalena Albelda-Berenguer
- Laboratory of Technologies for Heritage Materials, Institute of Chemistry, University of Neuchâtel, Neuchâtel, Switzerland
| | - Mathilde Monachon
- Laboratory of Technologies for Heritage Materials, Institute of Chemistry, University of Neuchâtel, Neuchâtel, Switzerland
| | - Edith Joseph
- Laboratory of Technologies for Heritage Materials, Institute of Chemistry, University of Neuchâtel, Neuchâtel, Switzerland; Haute Ecole Arc Conservation-Restauration, Neuchâtel, Switzerland.
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27
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Misslinger M, Lechner BE, Bacher K, Haas H. Iron-sensing is governed by mitochondrial, not by cytosolic iron-sulfur cluster biogenesis in Aspergillus fumigatus. Metallomics 2018; 10:1687-1700. [PMID: 30395137 PMCID: PMC6250123 DOI: 10.1039/c8mt00263k] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2018] [Accepted: 10/09/2018] [Indexed: 12/13/2022]
Abstract
Microorganisms have to adapt their metabolism to the requirements of their ecological niche to avoid iron shortage as well as iron toxicity. Therefore, mechanisms have been evolved to tightly regulate iron uptake, consumption, and detoxification, which depend on sensing the cellular iron status. In the facultative anaerobic yeast Saccharomyces cerevisiae, iron-sensing depends on mitochondrial (ISC) but not cytosolic iron-sulfur cluster assembly (CIA), while in mammals further processing of an ISC product via CIA is required for sensing of the cellular iron state. To address the question of how the obligatory aerobic mold Aspergillus fumigatus senses the cellular iron state, mutant strains allowing the downregulation of ISC and CIA were generated. These studies revealed that: (i) Nfs1 (Afu3g14240) and Nbp35 (Afu2g15960), which are involved in ISC and CIA, respectively, are essential for growth; (ii) a decrease in ISC (Nfs1 depletion) but not CIA (Nbp35 depletion) results in a transcriptional iron starvation response, (iii) a decrease in, ISC as well as CIA, increases the chelatable iron pool, accompanied by increased iron toxicity and increased susceptibility to oxidative stress and phleomycin. In agreement with ISC being essential for iron-sensing, a decrease in mitochondrial iron import by deletion of the mitochondrial iron importer MrsA resulted in an iron starvation response. Taken together, these data underline that iron-sensing in A. fumigatus depends on ISC but not CIA. Moreover, depletion of the glutathione pool via generating a mutant lacking γ-glutamylcysteine synthase, GshA (Afu3g13900), caused an iron starvation response, underlining a crucial role of glutathione in iron-sensing in A. fumigatus.
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Affiliation(s)
- Matthias Misslinger
- Division of Molecular Biology, Biocenter
, Medical University of Innsbruck
,
Innrain 80
, 6020 Innsbruck
, Austria
.
| | - Beatrix E. Lechner
- Division of Molecular Biology, Biocenter
, Medical University of Innsbruck
,
Innrain 80
, 6020 Innsbruck
, Austria
.
| | - Katharina Bacher
- Division of Molecular Biology, Biocenter
, Medical University of Innsbruck
,
Innrain 80
, 6020 Innsbruck
, Austria
.
| | - Hubertus Haas
- Division of Molecular Biology, Biocenter
, Medical University of Innsbruck
,
Innrain 80
, 6020 Innsbruck
, Austria
.
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28
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Intracellular Siderophore Detection in an Egyptian, Cobalt-Treated F. solani Isolate Using SEM-EDX with Reference to its Tolerance. Pol J Microbiol 2018; 66:235-243. [PMID: 28735319 DOI: 10.5604/01.3001.0010.7856] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
An Egyptian, plant pathogenic Fusarium solani isolate was grown on cobalt concentrations of 0, 50, 200, 500, 800, and 1000 ppm. The isolate survived concentrations up to 800 ppm, however failed to grow at 1000 ppm. Morphology and elemental analysis of the isolate under the investigated Co concentrations were studied using Scanning electron microscopy (SEM) and energy dispersive X-ray microanalysis (EDX). The isolate reserved its morphology up to a concentration of 200 ppm. Morphological distortions were dramatic at 500 and 800 ppm. EDX detected Co uptake through the hyphae, microconidia, macroconidia, and chlamydospores. Iron, calcium, and potassium were also detected. EDX results showed a linear relationship between Co% and Fe% up to a concentration of 500 ppm reflecting the possible ability of the isolate to synthesize intracellular siderophores storing iron and their release from the vacuoles. The participation of such siderophores in conferring tolerance against cobalt is discussed. At 800 ppm, the % of Fe was greatly reduced with an accompanying increase in morphological distortions and absence of microconidia. Increasing the implicated cobalt concentrations resulted in increasing the percentages of the chelated cobalt reflecting the possible implication of the cell wall as well as extracellular siderophores in the uptake of cobalt. The current results recommend the absence of cobalt in any control regime taken to combat the investigated F. solani isolate and highlights the accomplishment of biochemical, ultrastructural, and molecular studies on such isolate to approve the production of siderophores and the role of cell wall in cobalt uptake.
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29
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Contrasting roles of fungal siderophores in maintaining iron homeostasis in Epichloë festucae. Fungal Genet Biol 2018; 111:60-72. [DOI: 10.1016/j.fgb.2017.11.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Revised: 11/11/2017] [Accepted: 11/14/2017] [Indexed: 11/23/2022]
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30
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Gerwien F, Skrahina V, Kasper L, Hube B, Brunke S. Metals in fungal virulence. FEMS Microbiol Rev 2018; 42:4562650. [PMID: 29069482 PMCID: PMC5812535 DOI: 10.1093/femsre/fux050] [Citation(s) in RCA: 142] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2017] [Accepted: 10/19/2017] [Indexed: 12/25/2022] Open
Abstract
Metals are essential for life, and they play a central role in the struggle between infecting microbes and their hosts. In fact, an important aspect of microbial pathogenesis is the 'nutritional immunity', in which metals are actively restricted (or, in an extended definition of the term, locally enriched) by the host to hinder microbial growth and virulence. Consequently, fungi have evolved often complex regulatory networks, uptake and detoxification systems for essential metals such as iron, zinc, copper, nickel and manganese. These systems often differ fundamentally from their bacterial counterparts, but even within the fungal pathogens we can find common and unique solutions to maintain metal homeostasis. Thus, we here compare the common and species-specific mechanisms used for different metals among different fungal species-focusing on important human pathogens such as Candida albicans, Aspergillus fumigatus or Cryptococcus neoformans, but also looking at model fungi such as Saccharomyces cerevisiae or A. nidulans as well-studied examples for the underlying principles. These direct comparisons of our current knowledge reveal that we have a good understanding how model fungal pathogens take up iron or zinc, but that much is still to learn about other metals and specific adaptations of individual species-not the least to exploit this knowledge for new antifungal strategies.
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Affiliation(s)
- Franziska Gerwien
- Department Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology– Hans Knoell Institute, 07745 Jena, Germany
| | - Volha Skrahina
- Department Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology– Hans Knoell Institute, 07745 Jena, Germany
| | - Lydia Kasper
- Department Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology– Hans Knoell Institute, 07745 Jena, Germany
| | - Bernhard Hube
- Department Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology– Hans Knoell Institute, 07745 Jena, Germany
| | - Sascha Brunke
- Department Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology– Hans Knoell Institute, 07745 Jena, Germany
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31
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Rehman L, Su X, Li X, Qi X, Guo H, Cheng H. FreB is involved in the ferric metabolism and multiple pathogenicity-related traits of Verticillium dahliae. Curr Genet 2017; 64:645-659. [PMID: 29177887 DOI: 10.1007/s00294-017-0780-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2017] [Revised: 10/25/2017] [Accepted: 11/08/2017] [Indexed: 01/31/2023]
Abstract
Ferric reductases are integral membrane proteins involved in the reduction of environmental ferric iron into the biologically available ferrous iron. In the most overwhelming phytopathogenic fungus, Verticillium dahliae, these ferric reductase are not studied in details. In this study we explored the role of FreB gene (VDAG_06616) in the ferric reduction and virulence of V. dahliae by generating the knockout mutants (ΔFreB) and complementary strains (ΔFreB-C) using protoplast transformation. When cultured on media supplemented with FeSO4, FeCl3 and no iron, ΔFreB exhibited significantly reduced growth and spore production especially on media with no iron. Transmembrane ferric reductase activity of ΔFreB was decreased up to 50% than wild type strains (Vd-wt). The activity was fully restored in ΔFreB-C. Meanwhile, the expression levels of other related genes (Frect-4, Frect-5, Frect-6 and Met) were obviously increased in ΔFreB. Compared with the Vd-wt and ΔFreB-C, ΔFreB-1 and ΔFreB-2 were impaired in colony diameter and spore number on different carbon sources (starch, sucrose, galactose and xylose). ΔFreB-1 and ΔFreB-2 were also highly sensitive to oxidative stress as revealed by the plate diffusion assay when 100 µM H2O2 was applied to the fungal culture. When Nicotiana benthamiana plants were inoculated, ΔFreB exhibited less disease symptoms than Vd-wt and ΔFreB-C. In conclusion, the present findings not only indicate that FreB mediates the ferric metabolism and is required for the full virulence in V. dahliae, but would also accelerate future investigation to uncover the pathogenic mechanism of this fungus.
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Affiliation(s)
- Latifur Rehman
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Xiaofeng Su
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Xiaokang Li
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Xiliang Qi
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Huiming Guo
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China
| | - Hongmei Cheng
- Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
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32
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Sephton-Clark PCS, Voelz K. Spore Germination of Pathogenic Filamentous Fungi. ADVANCES IN APPLIED MICROBIOLOGY 2017; 102:117-157. [PMID: 29680124 DOI: 10.1016/bs.aambs.2017.10.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Fungi, algae, plants, protozoa, and bacteria are all known to form spores, especially hardy and ubiquitous propagation structures that are also often the infectious agents of diseases. Spores can survive for thousands of years, frozen in the permafrost (Kochkina et al., 2012), with the oldest viable spores extracted after 250 million years from salt crystals (Vreeland, Rosenzweig, & Powers, 2000). Their resistance to high levels of UV, desiccation, pressure, heat, and cold enables the survival of spores in the harshest conditions (Setlow, 2016). For example, Bacillus subtilis spores can survive and remain viable after experiencing conditions similar to those on Mars (Horneck et al., 2012). Spores are disseminated through environmental factors. Wind, water, or animal carriage allow spores to be spread ubiquitously throughout the environment. Spores will break dormancy and begin to germinate once exposed to favorable conditions. Germination is the mechanism that converts the spore from a dormant biological organism to one that grows vegetatively and is capable of either sexual or asexual reproduction. The process of germination has been well studied in plants, moss, bacteria, and many fungi (Hohe & Reski, 2005; Huang & Hull, 2017; Vesty et al., 2016). Unfortunately, information on the complex signaling involved in the regulation of germination, particularly in fungi remains lacking. This chapter will discuss germination of fungal spores covering our current understanding of the regulation, signaling, outcomes, and implications of germination of pathogenic fungal spores. Owing to the morphological similarities between the spore-hyphal and yeast-hyphal transition and their relevance for disease progression, relevant aspects of fungal dimorphism will be discussed alongside spore germination in this chapter.
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Affiliation(s)
- Poppy C S Sephton-Clark
- School of Biosciences, Institute of Microbiology and Infection, University of Birmingham, Birmingham, United Kingdom
| | - Kerstin Voelz
- School of Biosciences, Institute of Microbiology and Infection, University of Birmingham, Birmingham, United Kingdom.
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33
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Sun X, Zhao Y, Jia J, Xie J, Cheng J, Liu H, Jiang D, Fu Y. Uninterrupted Expression of CmSIT1 in a Sclerotial Parasite Coniothyrium minitans Leads to Reduced Growth and Enhanced Antifungal Ability. Front Microbiol 2017; 8:2208. [PMID: 29176968 PMCID: PMC5686095 DOI: 10.3389/fmicb.2017.02208] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Accepted: 10/26/2017] [Indexed: 01/02/2023] Open
Abstract
Coniothyrium minitans is an important mycoparasite of Sclerotinia sclerotiorum. In addition, it also produces small amounts of antifungal substances. ZS-1TN1812, an abnormal mutant, was originally screened from a T-DNA insertional library. This mutant showed abnormal growth phenotype and could significantly inhibit the growth of S. sclerotiorum when dual-cultured on a PDA plate. When spraying the filtrate of ZS-1TN1812 on the leaves of rapeseed, S. sclerotiorum infection was significantly inhibited, suggesting that the antifungal substances produced by this mutant were effective on rapeseed leaves. The thermo-tolerant antifungal substances could specifically suppress the growth of S. sclerotiorum, but could not significantly suppress the growth of another fungus, Colletotrichum higginsianum. However, C. higginsianum was more sensitive to proteinous antibiotics than S. sclerotiorum. The T-DNA insertion in ZS-1TN1812 activated the expression of CmSIT1, a gene involved in siderophore-mediated iron transport. It was also determined that mutant ZS-1TN1812 produced hypha with high iron levels. In the wild-type strain ZS-1, CmSIT1 was expressed only when in contact with S. sclerotiorum, and consistent overexpression of CmSIT1 showed similar phenotypes as ZS-1TN1812. Therefore, activated expression of CmSIT1 leads to the enhanced antifungal ability, and CmSIT1 is a potential gene for improving the control ability of C. minitans.
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Affiliation(s)
- Xiping Sun
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
- The Provincial Key Lab of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Ying Zhao
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
- The Provincial Key Lab of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Jichun Jia
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
- The Provincial Key Lab of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Jiatao Xie
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
- The Provincial Key Lab of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Jiasen Cheng
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
- The Provincial Key Lab of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Huiquan Liu
- State Key Laboratory of Crop Stress Biology for Arid Areas, College of Plant Protection, Northwest Agriculture and Forestry University, Yangling, China
| | - Daohong Jiang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
- The Provincial Key Lab of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
| | - Yanping Fu
- The Provincial Key Lab of Plant Pathology of Hubei Province, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan, China
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34
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Khan A, Singh P, Srivastava A. Synthesis, nature and utility of universal iron chelator - Siderophore: A review. Microbiol Res 2017; 212-213:103-111. [PMID: 29103733 DOI: 10.1016/j.micres.2017.10.012] [Citation(s) in RCA: 181] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2017] [Revised: 10/10/2017] [Accepted: 10/27/2017] [Indexed: 12/16/2022]
Abstract
Siderophores, the secondary metabolite of various microorganisms are ferric ion specific chelators secreted under iron stressed condition. These non-ribosomal peptides have been classified as catecholate, hydroxamate, carboxylate and mixed types. Recent studies focus on discovery of possible mammalian siderophores. The biosynthesis pathway including non-ribosomal dependent as well as non-ribosomal independent pathways are of great interest now a days. Many significant roles of siderophores such as virulence in pathogens, oxidative stress tolerance, classification of organisms etc. are being discovered. Studies on siderophore utilization in bioremediation and other heavy metal chelation have increased in past decade. The iron chelation ability of siderophores is being recently studied with regards to malignant cancerous cells. Not only this, it has been found that they possess antimicrobial properties which can be utilized against number of microbes. This review covers all recent aspects of siderophore and its applications.
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Affiliation(s)
- Azmi Khan
- Life Science Programme, Centre for Biological Sciences, Central University of South Bihar, Patna 800014, India
| | - Pratika Singh
- Life Science Programme, Centre for Biological Sciences, Central University of South Bihar, Patna 800014, India
| | - Amrita Srivastava
- Life Science Programme, Centre for Biological Sciences, Central University of South Bihar, Patna 800014, India.
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35
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Vicente VA, Weiss VA, Bombassaro A, Moreno LF, Costa FF, Raittz RT, Leão AC, Gomes RR, Bocca AL, Fornari G, de Castro RJA, Sun J, Faoro H, Tadra-Sfeir MZ, Baura V, Balsanelli E, Almeida SR, Dos Santos SS, Teixeira MDM, Soares Felipe MS, do Nascimento MMF, Pedrosa FO, Steffens MB, Attili-Angelis D, Najafzadeh MJ, Queiroz-Telles F, Souza EM, De Hoog S. Comparative Genomics of Sibling Species of Fonsecaea Associated with Human Chromoblastomycosis. Front Microbiol 2017; 8:1924. [PMID: 29062304 PMCID: PMC5640708 DOI: 10.3389/fmicb.2017.01924] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2017] [Accepted: 09/21/2017] [Indexed: 01/16/2023] Open
Abstract
Fonsecaea and Cladophialophora are genera of black yeast-like fungi harboring agents of a mutilating implantation disease in humans, along with strictly environmental species. The current hypothesis suggests that those species reside in somewhat adverse microhabitats, and pathogenic siblings share virulence factors enabling survival in mammal tissue after coincidental inoculation driven by pathogenic adaptation. A comparative genomic analysis of environmental and pathogenic siblings of Fonsecaea and Cladophialophora was undertaken, including de novo assembly of F. erecta from plant material. The genome size of Fonsecaea species varied between 33.39 and 35.23 Mb, and the core genomes of those species comprises almost 70% of the genes. Expansions of protein domains such as glyoxalases and peptidases suggested ability for pathogenicity in clinical agents, while the use of nitrogen and degradation of phenolic compounds was enriched in environmental species. The similarity of carbohydrate-active vs. protein-degrading enzymes associated with the occurrence of virulence factors suggested a general tolerance to extreme conditions, which might explain the opportunistic tendency of Fonsecaea sibling species. Virulence was tested in the Galleria mellonella model and immunological assays were performed in order to support this hypothesis. Larvae infected by environmental F. erecta had a lower survival. Fungal macrophage murine co-culture showed that F. erecta induced high levels of TNF-α contributing to macrophage activation that could increase the ability to control intracellular fungal growth although hyphal death were not observed, suggesting a higher level of extremotolerance of environmental species.
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Affiliation(s)
- Vania A Vicente
- Microbiology, Parasitology and Pathology Post-Graduation Program, Department of Basic Pathology, Federal University of Paraná, Curitiba, Brazil.,Bioprocess Engineering and Biotechnology, Federal University of Paraná, Curitiba, Brazil
| | - Vinícius A Weiss
- Laboratory of Bioinformatics, Sector of Technological and Professional Education, Federal University of Paraná, Curitiba, Brazil.,Department of Biochemistry, Federal University of Paraná, Curitiba, Brazil
| | - Amanda Bombassaro
- Microbiology, Parasitology and Pathology Post-Graduation Program, Department of Basic Pathology, Federal University of Paraná, Curitiba, Brazil
| | - Leandro F Moreno
- Microbiology, Parasitology and Pathology Post-Graduation Program, Department of Basic Pathology, Federal University of Paraná, Curitiba, Brazil.,CBS-KNAW Fungal Biodiversity Centre, Utrecht, Netherlands.,Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, Netherlands
| | - Flávia F Costa
- Bioprocess Engineering and Biotechnology, Federal University of Paraná, Curitiba, Brazil
| | - Roberto T Raittz
- Laboratory of Bioinformatics, Sector of Technological and Professional Education, Federal University of Paraná, Curitiba, Brazil
| | - Aniele C Leão
- Bioprocess Engineering and Biotechnology, Federal University of Paraná, Curitiba, Brazil.,Laboratory of Bioinformatics, Sector of Technological and Professional Education, Federal University of Paraná, Curitiba, Brazil.,Department of Biochemistry, Federal University of Paraná, Curitiba, Brazil
| | - Renata R Gomes
- Microbiology, Parasitology and Pathology Post-Graduation Program, Department of Basic Pathology, Federal University of Paraná, Curitiba, Brazil
| | - Anamelia L Bocca
- Department of Cell Biology, University of Brasília, Brasilia, Brazil
| | - Gheniffer Fornari
- Microbiology, Parasitology and Pathology Post-Graduation Program, Department of Basic Pathology, Federal University of Paraná, Curitiba, Brazil
| | | | - Jiufeng Sun
- Guangdong Provincial Institute of Public Health, Guangdong Provincial Center for Disease Control and Prevention, Guangzhou, China
| | - Helisson Faoro
- Department of Biochemistry, Federal University of Paraná, Curitiba, Brazil
| | | | - Valter Baura
- Department of Biochemistry, Federal University of Paraná, Curitiba, Brazil
| | - Eduardo Balsanelli
- Department of Biochemistry, Federal University of Paraná, Curitiba, Brazil
| | - Sandro R Almeida
- Department of Clinical and Toxicological Analysis, Faculty of Pharmaceutical Sciences, University of São Paulo, Sao Paulo, Brazil
| | - Suelen S Dos Santos
- Department of Clinical and Toxicological Analysis, Faculty of Pharmaceutical Sciences, University of São Paulo, Sao Paulo, Brazil
| | - Marcus de Melo Teixeira
- Department of Cell Biology, University of Brasília, Brasilia, Brazil.,Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ, United States
| | - Maria S Soares Felipe
- Department of Genomic Sciences and Biotechnology, Catholic University of Brasília, Brasilia, Brazil
| | | | - Fabio O Pedrosa
- Department of Biochemistry, Federal University of Paraná, Curitiba, Brazil
| | - Maria B Steffens
- Laboratory of Bioinformatics, Sector of Technological and Professional Education, Federal University of Paraná, Curitiba, Brazil.,Department of Biochemistry, Federal University of Paraná, Curitiba, Brazil
| | | | - Mohammad J Najafzadeh
- Department of Parasitology and Mycology, School of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Flávio Queiroz-Telles
- Microbiology, Parasitology and Pathology Post-Graduation Program, Department of Basic Pathology, Federal University of Paraná, Curitiba, Brazil.,Clinical Hospital of the Federal University of Paraná, Curitiba, Brazil
| | - Emanuel M Souza
- Laboratory of Bioinformatics, Sector of Technological and Professional Education, Federal University of Paraná, Curitiba, Brazil.,Department of Biochemistry, Federal University of Paraná, Curitiba, Brazil
| | - Sybren De Hoog
- Microbiology, Parasitology and Pathology Post-Graduation Program, Department of Basic Pathology, Federal University of Paraná, Curitiba, Brazil.,CBS-KNAW Fungal Biodiversity Centre, Utrecht, Netherlands.,Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Amsterdam, Netherlands
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Rätsep M, Kõljalg S, Sepp E, Smidt I, Truusalu K, Songisepp E, Stsepetova J, Naaber P, Mikelsaar RH, Mikelsaar M. A combination of the probiotic and prebiotic product can prevent the germination of Clostridium difficile spores and infection. Anaerobe 2017; 47:94-103. [PMID: 28465256 DOI: 10.1016/j.anaerobe.2017.03.019] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2016] [Revised: 03/23/2017] [Accepted: 03/28/2017] [Indexed: 12/17/2022]
Abstract
Clostridium difficile infection (CDI) is one of the most prevalent healthcare associated infections in hospitals and nursing homes. Different approaches are used for prevention of CDI. Absence of intestinal lactobacilli and bifidobacteria has been associated with C. difficile colonization in hospitalized patients. Our aim was to test a) the susceptibility of C. difficile strains of different origin and the intestinal probiotic Lactobacillus plantarum Inducia (DSM 21379) to various antimicrobial preparations incl. metronidazole, vancomycin; b) the susceptibility of C. difficile strains to antagonistic effects of the probiotic L. plantarum Inducia, prebiotic xylitol (Xyl) and their combination as a synbiotic (Syn) product; c) the suppression of germination of C. difficile spores in vitro and in vivo in animal model of C. difficile infection with Inducia, Xyl and Syn treatment. The VPI strain 10463 (ATCC 43255), epidemic strain (M 13042) and clinical isolates (n = 12) of C. difficile from Norway and Estonia were susceptible and contrarily L. plantarum Inducia resistant to vancomycin, metronidazole and ciprofloxacin. The intact cells of Inducia, natural and neutralized cell free supernatant inhibited in vitro the growth of tested C. difficile reference strain VPI and Estonian and Norwegian clinical isolates of C. difficile after co-cultivation. This effect against C. difficile sustained in liquid media under ampicillin (0.75 μg/ml) and Xyl (5%) application. Further, incubation of Inducia in the media with 5% Xyl fully stopped germination of spores of C. difficile VPI strain after 48 h. In infection model the 48 hamsters were administered ampicillin (30 mg/kg) and 10-30 spores of C. difficile VPI strain. They also received five days before and after the challenge a pretreatment with a synbiotic (single daily dose of L. plantarum Inducia 1 ml of 1010 CFU/ml and 20% xylitol in 1 ml by orogastric gavage). The survival rate of hamsters was increased to 78% compared to 13% (p = 0.003) survival rate of hamsters who received no treatment. When administered Xyl the survival rate of hamsters reached 56% vs.13% (p = 0.06). In both Syn (6/9, p = 0.003) and Xyl (3/9, p = 0.042) groups the number of animals not colonized with C. difficile significantly increased. In conclusion, the combination of xylitol with L. plantarum Inducia suppresses the germination of spores and outgrowth into vegetative toxin producing cells of C. difficile and reduces the colonization of gut with the pathogen. Putative therapeutical approach includes usage of the synbiotic during antimicrobial therapy for prevention of CDI and its potential to reduce recurrences of CDI.
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Affiliation(s)
- M Rätsep
- Institute of Biomedicine and Translational Medicine, University of Tartu, EE 50411, Estonia; Bio-Competence Centre of Healthy Dairy Products LLC, EE 51014, Estonia
| | - S Kõljalg
- Institute of Biomedicine and Translational Medicine, University of Tartu, EE 50411, Estonia
| | - E Sepp
- Institute of Biomedicine and Translational Medicine, University of Tartu, EE 50411, Estonia
| | - I Smidt
- Institute of Biomedicine and Translational Medicine, University of Tartu, EE 50411, Estonia
| | - K Truusalu
- Institute of Biomedicine and Translational Medicine, University of Tartu, EE 50411, Estonia
| | - E Songisepp
- Bio-Competence Centre of Healthy Dairy Products LLC, EE 51014, Estonia
| | - J Stsepetova
- Institute of Biomedicine and Translational Medicine, University of Tartu, EE 50411, Estonia
| | - P Naaber
- Institute of Biomedicine and Translational Medicine, University of Tartu, EE 50411, Estonia
| | - R H Mikelsaar
- Institute of Biomedicine and Translational Medicine, University of Tartu, EE 50411, Estonia
| | - M Mikelsaar
- Institute of Biomedicine and Translational Medicine, University of Tartu, EE 50411, Estonia; Bio-Competence Centre of Healthy Dairy Products LLC, EE 51014, Estonia.
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37
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Penselin D, Münsterkötter M, Kirsten S, Felder M, Taudien S, Platzer M, Ashelford K, Paskiewicz KH, Harrison RJ, Hughes DJ, Wolf T, Shelest E, Graap J, Hoffmann J, Wenzel C, Wöltje N, King KM, Fitt BDL, Güldener U, Avrova A, Knogge W. Comparative genomics to explore phylogenetic relationship, cryptic sexual potential and host specificity of Rhynchosporium species on grasses. BMC Genomics 2016; 17:953. [PMID: 27875982 PMCID: PMC5118889 DOI: 10.1186/s12864-016-3299-5] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2016] [Accepted: 11/15/2016] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND The Rhynchosporium species complex consists of hemibiotrophic fungal pathogens specialized to different sweet grass species including the cereal crops barley and rye. A sexual stage has not been described, but several lines of evidence suggest the occurrence of sexual reproduction. Therefore, a comparative genomics approach was carried out to disclose the evolutionary relationship of the species and to identify genes demonstrating the potential for a sexual cycle. Furthermore, due to the evolutionary very young age of the five species currently known, this genus appears to be well-suited to address the question at the molecular level of how pathogenic fungi adapt to their hosts. RESULTS The genomes of the different Rhynchosporium species were sequenced, assembled and annotated using ab initio gene predictors trained on several fungal genomes as well as on Rhynchosporium expressed sequence tags. Structures of the rDNA regions and genome-wide single nucleotide polymorphisms provided a hypothesis for intra-genus evolution. Homology screening detected core meiotic genes along with most genes crucial for sexual recombination in ascomycete fungi. In addition, a large number of cell wall-degrading enzymes that is characteristic for hemibiotrophic and necrotrophic fungi infecting monocotyledonous hosts were found. Furthermore, the Rhynchosporium genomes carry a repertoire of genes coding for polyketide synthases and non-ribosomal peptide synthetases. Several of these genes are missing from the genome of the closest sequenced relative, the poplar pathogen Marssonina brunnea, and are possibly involved in adaptation to the grass hosts. Most importantly, six species-specific genes coding for protein effectors were identified in R. commune. Their deletion yielded mutants that grew more vigorously in planta than the wild type. CONCLUSION Both cryptic sexuality and secondary metabolites may have contributed to host adaptation. Most importantly, however, the growth-retarding activity of the species-specific effectors suggests that host adaptation of R. commune aims at extending the biotrophic stage at the expense of the necrotrophic stage of pathogenesis. Like other apoplastic fungi Rhynchosporium colonizes the intercellular matrix of host leaves relatively slowly without causing symptoms, reminiscent of the development of endophytic fungi. Rhynchosporium may therefore become an object for studying the mutualism-parasitism transition.
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Affiliation(s)
- Daniel Penselin
- Department of Stress and Developmental Biology, Leibniz Institute of Plant Biochemistry, Halle/Saale, Germany
| | - Martin Münsterkötter
- Institute of Bioinformatics and Systems Biology, Helmholtz Zentrum München, Neuherberg, Germany
| | - Susanne Kirsten
- Department of Stress and Developmental Biology, Leibniz Institute of Plant Biochemistry, Halle/Saale, Germany
| | - Marius Felder
- Genomic Analysis, Leibniz Institute on Aging, Fritz Lipmann Institute, Jena, Germany
| | - Stefan Taudien
- Genomic Analysis, Leibniz Institute on Aging, Fritz Lipmann Institute, Jena, Germany
| | - Matthias Platzer
- Genomic Analysis, Leibniz Institute on Aging, Fritz Lipmann Institute, Jena, Germany
| | - Kevin Ashelford
- Institute of Medical Genetics, Cardiff University, Cardiff, UK
| | | | | | - David J. Hughes
- Applied Bioinformatics, Rothamsted Research, Harpenden, Hertfordshire UK
| | - Thomas Wolf
- Systems Biology and Bioinformatics, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute, Jena, Germany
| | - Ekaterina Shelest
- Systems Biology and Bioinformatics, Leibniz Institute for Natural Product Research and Infection Biology, Hans Knöll Institute, Jena, Germany
| | - Jenny Graap
- Department of Stress and Developmental Biology, Leibniz Institute of Plant Biochemistry, Halle/Saale, Germany
| | - Jan Hoffmann
- Department of Stress and Developmental Biology, Leibniz Institute of Plant Biochemistry, Halle/Saale, Germany
| | - Claudia Wenzel
- Department of Stress and Developmental Biology, Leibniz Institute of Plant Biochemistry, Halle/Saale, Germany ,Present address: Food Quality and Nutrition, Agroscope, Bern, Switzerland
| | - Nadine Wöltje
- Department of Stress and Developmental Biology, Leibniz Institute of Plant Biochemistry, Halle/Saale, Germany
| | - Kevin M. King
- Biological Chemistry and Crop Protection, Rothamsted Research, Harpenden, Hertfordshire UK
| | - Bruce D. L. Fitt
- Biological and Environmental Sciences, University of Hertfordshire, Hatfield, Hertfordshire UK
| | - Ulrich Güldener
- Department of Genome-Oriented Bioinformatics, Technische Universität München, Wissenschaftszentrum Weihenstephan, Freising, Germany
| | - Anna Avrova
- Cell and Molecular Sciences, The James Hutton Institute, Invergowrie, Dundee, Scotland
| | - Wolfgang Knogge
- Department of Stress and Developmental Biology, Leibniz Institute of Plant Biochemistry, Halle/Saale, Germany
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Balhara M, Chaudhary R, Ruhil S, Singh B, Dahiya N, Parmar VS, Jaiwal PK, Chhillar AK. Siderophores; iron scavengers: the novel & promising targets for pathogen specific antifungal therapy. Expert Opin Ther Targets 2016; 20:1477-1489. [PMID: 27797604 DOI: 10.1080/14728222.2016.1254196] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
Abstract
INTRODUCTION The recent emergence of resistance, toxicity paradigm and limited efficacy of conventional antifungal drugs necessitate the identification of de novo targets in fungal metabolism. One of the most critical physiological processes during in vivo pathogenesis is maintenance of iron homeostasis. The most life threatening opportunistic human fungal pathogens like Aspergillus, Candida and Cryptococcus exploit the siderophore mediated iron uptake mechanism either for survival, virulence, propagation or resistance to oxidative stress envisaged in vivo during infection. Areas covered: In this review, we will highlight the metabolic pathways; specifically siderophore biosynthesis, uptake and utilisation, triggered in the fungal pathogens in iron starving conditions and the various putative targets viable in these pathways to be recruited as novel therapeutic antidotes either via biosynthetic enzymes catalytic site inhibitors or as drug conjugates through trojan horse approach and further role in the development of fungal specific reliable diagnostic markers. Expert opinion: Siderophores are the weapons released by a pathogen to conquer the battle for iron acquisition. Hence, the fungal siderophore biosynthetic pathways along with their uptake and utilisation mechanisms represent an ideal target for pathogen specific, host friendly therapeutic strategy which would block the proliferation of parasite without causing any harm to the mammalian host.
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Affiliation(s)
- Meenakshi Balhara
- a Centre for Biotechnology , Maharshi Dayanand University , Rohtak , Haryana , India
| | - Renu Chaudhary
- a Centre for Biotechnology , Maharshi Dayanand University , Rohtak , Haryana , India
| | - Sonam Ruhil
- a Centre for Biotechnology , Maharshi Dayanand University , Rohtak , Haryana , India
| | - Bharat Singh
- a Centre for Biotechnology , Maharshi Dayanand University , Rohtak , Haryana , India
| | - Nisha Dahiya
- b Division of Epidemiology and Communicable Diseases , Indian Council of Medical Research , Delhi , India
| | - Virinder S Parmar
- c Bioorganic Laboratory, Department of Chemistry , University of Delhi , Delhi , India
| | - Pawan K Jaiwal
- a Centre for Biotechnology , Maharshi Dayanand University , Rohtak , Haryana , India
| | - Anil K Chhillar
- a Centre for Biotechnology , Maharshi Dayanand University , Rohtak , Haryana , India
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Sheridan KJ, Lechner BE, Keeffe GO, Keller MA, Werner ER, Lindner H, Jones GW, Haas H, Doyle S. Ergothioneine Biosynthesis and Functionality in the Opportunistic Fungal Pathogen, Aspergillus fumigatus. Sci Rep 2016; 6:35306. [PMID: 27748436 PMCID: PMC5066259 DOI: 10.1038/srep35306] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 08/03/2016] [Indexed: 12/11/2022] Open
Abstract
Ergothioneine (EGT; 2-mercaptohistidine trimethylbetaine) is a trimethylated and sulphurised histidine derivative which exhibits antioxidant properties. Here we report that deletion of Aspergillus fumigatus egtA (AFUA_2G15650), which encodes a trimodular enzyme, abrogated EGT biosynthesis in this opportunistic pathogen. EGT biosynthetic deficiency in A. fumigatus significantly reduced resistance to elevated H2O2 and menadione, respectively, impaired gliotoxin production and resulted in attenuated conidiation. Quantitative proteomic analysis revealed substantial proteomic remodelling in ΔegtA compared to wild-type under both basal and ROS conditions, whereby the abundance of 290 proteins was altered. Specifically, the reciprocal differential abundance of cystathionine γ-synthase and β-lyase, respectively, influenced cystathionine availability to effect EGT biosynthesis. A combined deficiency in EGT biosynthesis and the oxidative stress response regulator Yap1, which led to extreme oxidative stress susceptibility, decreased resistance to heavy metals and production of the extracellular siderophore triacetylfusarinine C and increased accumulation of the intracellular siderophore ferricrocin. EGT dissipated H2O2 in vitro, and elevated intracellular GSH levels accompanied abrogation of EGT biosynthesis. EGT deficiency only decreased resistance to high H2O2 levels which suggests functionality as an auxiliary antioxidant, required for growth at elevated oxidative stress conditions. Combined, these data reveal new interactions between cellular redox homeostasis, secondary metabolism and metal ion homeostasis.
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Affiliation(s)
- Kevin J Sheridan
- Department of Biology, Maynooth University, Maynooth, Co. Kildare, Ireland
| | | | - Grainne O' Keeffe
- Department of Biology, Maynooth University, Maynooth, Co. Kildare, Ireland
| | - Markus A Keller
- Division of Biological Chemistry, Biocenter, Medical University Innsbruck, Innrain 80/82, Austria
| | - Ernst R Werner
- Division of Biological Chemistry, Biocenter, Medical University Innsbruck, Innrain 80/82, Austria
| | - Herbert Lindner
- Division of Clinical Biochemistry, Biocenter, Medical University Innsbruck, Innrain 80/82, Austria
| | - Gary W Jones
- Department of Biology, Maynooth University, Maynooth, Co. Kildare, Ireland
| | - Hubertus Haas
- Division of Molecular Biology, Biocenter, Medical University Innsbruck, Innrain 80/82, Austria
| | - Sean Doyle
- Department of Biology, Maynooth University, Maynooth, Co. Kildare, Ireland
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40
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Pasricha S, Schafferer L, Lindner H, Joanne Boyce K, Haas H, Andrianopoulos A. Differentially regulated high-affinity iron assimilation systems support growth of the various cell types in the dimorphic pathogenTalaromyces marneffei. Mol Microbiol 2016; 102:715-737. [DOI: 10.1111/mmi.13489] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/22/2016] [Indexed: 01/07/2023]
Affiliation(s)
- Shivani Pasricha
- Department of Genetics; University of Melbourne; Victoria 3010 Australia
| | - Lukas Schafferer
- Division of Molecular Biology and Division of Clinical Biochemistry and the Protein Micro-Analysis Facility; Innsbruck Medical University; Innsbruck, Innrain 80-82 Innsbruck A-6020 Austria
| | - Herbert Lindner
- Division of Molecular Biology and Division of Clinical Biochemistry and the Protein Micro-Analysis Facility; Innsbruck Medical University; Innsbruck, Innrain 80-82 Innsbruck A-6020 Austria
| | - Kylie Joanne Boyce
- Department of Genetics; University of Melbourne; Victoria 3010 Australia
| | - Hubertus Haas
- Division of Molecular Biology and Division of Clinical Biochemistry and the Protein Micro-Analysis Facility; Innsbruck Medical University; Innsbruck, Innrain 80-82 Innsbruck A-6020 Austria
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Toh YF, Yew SM, Chan CL, Na SL, Lee KW, Hoh CC, Yee WY, Ng KP, Kuan CS. Genome Anatomy of Pyrenochaeta unguis-hominis UM 256, a Multidrug Resistant Strain Isolated from Skin Scraping. PLoS One 2016; 11:e0162095. [PMID: 27626635 PMCID: PMC5023194 DOI: 10.1371/journal.pone.0162095] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2016] [Accepted: 08/17/2016] [Indexed: 11/18/2022] Open
Abstract
Pyrenochaeta unguis-hominis is a rare human pathogen that causes infection in human skin and nail. P. unguis-hominis has received little attention, and thus, the basic biology and pathogenicity of this fungus is not fully understood. In this study, we performed in-depth analysis of the P. unguis-hominis UM 256 genome that was isolated from the skin scraping of a dermatitis patient. The isolate was identified to species level using a comprehensive multilocus phylogenetic analysis of the genus Pyrenochaeta. The assembled UM 256 genome has a size of 35.5 Mb and encodes 12,545 putative genes, and 0.34% of the assembled genome is predicted transposable elements. Its genomic features propose that the fungus is a heterothallic fungus that encodes a wide array of plant cell wall degrading enzymes, peptidases, and secondary metabolite biosynthetic enzymes. Antifungal drug resistance genes including MDR, CDR, and ERG11/CYP51 were identified in P. unguis-hominis UM 256, which may confer resistance to this fungus. The genome analysis of P. unguis-hominis provides an insight into molecular and genetic basis of the fungal lifestyles, understanding the unrevealed biology of antifungal resistance in this fungus.
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Affiliation(s)
- Yue Fen Toh
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Su Mei Yew
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Chai Ling Chan
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Shiang Ling Na
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Kok Wei Lee
- Codon Genomics SB, Seri Kembangan, Selangor Darul Ehsan, Malaysia
| | - Chee-Choong Hoh
- Codon Genomics SB, Seri Kembangan, Selangor Darul Ehsan, Malaysia
| | - Wai-Yan Yee
- Codon Genomics SB, Seri Kembangan, Selangor Darul Ehsan, Malaysia
| | - Kee Peng Ng
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
| | - Chee Sian Kuan
- Department of Medical Microbiology, Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia
- * E-mail:
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42
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Generation of new compounds through unbalanced transcription of landomycin A cluster. Appl Microbiol Biotechnol 2016; 100:9175-9186. [DOI: 10.1007/s00253-016-7721-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 06/28/2016] [Accepted: 06/30/2016] [Indexed: 11/26/2022]
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43
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Li Y, Wang Z, Liu X, Song Z, Li R, Shao C, Yin Y. Siderophore Biosynthesis but Not Reductive Iron Assimilation Is Essential for the Dimorphic Fungus Nomuraea rileyi Conidiation, Dimorphism Transition, Resistance to Oxidative Stress, Pigmented Microsclerotium Formation, and Virulence. Front Microbiol 2016; 7:931. [PMID: 27379061 PMCID: PMC4909778 DOI: 10.3389/fmicb.2016.00931] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2016] [Accepted: 05/31/2016] [Indexed: 12/04/2022] Open
Abstract
Iron is an indispensable factor for the dimorphic insect pathogenic Nomuraea rileyi to form persistent microsclerotia which can replace conidia or blastospores for commercial mass production. There are two high affinity iron acquisition pathways in N. rileyi, siderophore-assisted iron mobilization and reductive iron assimilation systems. Transcription of the two iron uptake pathways related genes is induced under iron-limiting conditions. Stage-specific iron uptake-related genes expression during microsclerotia development shows siderophore-mediated iron acquisition genes are rigorously upregulated specifically during the formation and mature period while reductive iron assimilation related genes just display a higher expression at the late maturation period. Abrogation of reductive iron assimilation, by the deletion of the high affinity iron permease (NrFtrA), has no visible effect on microsclerotia biogenesis in N. rileyi. In sharp contrast, N. rileyi L-ornithine-N5-monooxygenase (NrSidA), required for synthesis of all siderophores, is absolutely necessary for the development of pigmented microsclerotia. In agreement with the lower intracellular iron contents of microsclerotia in ΔNrSidA strains, not only the pigments, but both the number and the biomass are also noticeably reduced. Certain concentration of ROS is required for promoting microsclerotia biogenesis. Combined with expression pattern analysis of related genes and quantitative of intracellular iron or extracellular siderophore in WT and mutants, these data demonstrate the lack of adequate intracellular iron caused by the loss of the siderophore results in the deficiency of ROS detoxication. Furthermore, ΔNrSidA strains show significantly increased sensitivity to hydrogen peroxide. Besides, NrSidA, but not NrFtrA, play a crucial role in vegetative growth under iron-limiting conditions, conidiation, and dimorphic switching. Remarkably, the slower growth of the ΔNrSidA strains in vivo due to a reduced capacity for iron acquisition leads to the loss of virulence in Spodoptera litura while the ΔNrFtrA mutants behaved as WT during infection. Together, these results prove siderophore-assisted iron mobilization is the major pathway of cellular iron uptake and essential for conidiation, dimorphism transition, oxidative stress resistance, pigmented microsclerotium formation and full virulence.
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Affiliation(s)
- Yan Li
- Chongqing Engineering Research Center for Fungal Insecticides, School of Life Science, Chongqing University Chongqing, China
| | - Zhongkang Wang
- Chongqing Engineering Research Center for Fungal Insecticides, School of Life Science, Chongqing University Chongqing, China
| | - Xuee Liu
- Chongqing Engineering Research Center for Fungal Insecticides, School of Life Science, Chongqing University Chongqing, China
| | - Zhangyong Song
- Chongqing Engineering Research Center for Fungal Insecticides, School of Life Science, Chongqing University Chongqing, China
| | - Ren Li
- Chongqing Engineering Research Center for Fungal Insecticides, School of Life Science, Chongqing University Chongqing, China
| | - Changwen Shao
- Chongqing Engineering Research Center for Fungal Insecticides, School of Life Science, Chongqing University Chongqing, China
| | - Youping Yin
- Chongqing Engineering Research Center for Fungal Insecticides, School of Life Science, Chongqing University Chongqing, China
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44
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Peralta DR, Adler C, Corbalán NS, Paz García EC, Pomares MF, Vincent PA. Enterobactin as Part of the Oxidative Stress Response Repertoire. PLoS One 2016; 11:e0157799. [PMID: 27310257 PMCID: PMC4911079 DOI: 10.1371/journal.pone.0157799] [Citation(s) in RCA: 67] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2016] [Accepted: 06/03/2016] [Indexed: 12/28/2022] Open
Abstract
Microorganisms produce siderophores to facilitate iron uptake and even though this trait has been extensively studied, there is growing evidence suggesting that siderophores may have other physiological roles aside from iron acquisition. In support of this notion, we previously linked the archetypal siderophore enterobactin with oxidative stress alleviation. To further characterize this association, we studied the sensitivity of Escherichia coli strains lacking different components of the enterobactin system to the classical oxidative stressors hydrogen peroxide and paraquat. We observed that strains impaired in enterobactin production, uptake and hydrolysis were more susceptible to the oxidative damage caused by both compounds than the wild-type strain. In addition, meanwhile iron supplementation had little impact on the sensitivity, the reducing agent ascorbic acid alleviated the oxidative stress and therefore significantly decreased the sensitivity to the stressors. This indicated that the enterobactin-mediated protection is independent of its ability to scavenge iron. Furthermore, enterobactin supplementation conferred resistance to the entE mutant but did not have any protective effect on the fepG and fes mutants. Thus, we inferred that only after enterobactin is hydrolysed by Fes in the cell cytoplasm and iron is released, the free hydroxyl groups are available for radical stabilization. This hypothesis was validated testing the ability of enterobactin to scavenge radicals in vitro. Given the strong connection between enterobactin and oxidative stress, we studied the transcription of the entE gene and the concomitant production of the siderophore in response to such kind of stress. Interestingly, we observed that meanwhile iron represses the expression and production of the siderophore, hydrogen peroxide and paraquat favour these events even if iron is present. Our results support the involvement of enterobactin as part of the oxidative stress response and highlight the existence of a novel regulation mechanism for enterobactin biosynthesis.
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Affiliation(s)
- Daiana R. Peralta
- Instituto Superior de Investigaciones Biológicas (INSIBIO), CONICET-UNT and Instituto de Química Biológica “Dr. Bernabé Bloj”, Facultad de Bioquímica, Química y Farmacia, UNT. Chacabuco 461, T4000ILI -San Miguel de Tucumán, Tucumán, Argentina
| | - Conrado Adler
- Instituto Superior de Investigaciones Biológicas (INSIBIO), CONICET-UNT and Instituto de Química Biológica “Dr. Bernabé Bloj”, Facultad de Bioquímica, Química y Farmacia, UNT. Chacabuco 461, T4000ILI -San Miguel de Tucumán, Tucumán, Argentina
| | - Natalia S. Corbalán
- Instituto Superior de Investigaciones Biológicas (INSIBIO), CONICET-UNT and Instituto de Química Biológica “Dr. Bernabé Bloj”, Facultad de Bioquímica, Química y Farmacia, UNT. Chacabuco 461, T4000ILI -San Miguel de Tucumán, Tucumán, Argentina
| | - Enrique Carlos Paz García
- Instituto Superior de Investigaciones Biológicas (INSIBIO), CONICET-UNT and Instituto de Química Biológica “Dr. Bernabé Bloj”, Facultad de Bioquímica, Química y Farmacia, UNT. Chacabuco 461, T4000ILI -San Miguel de Tucumán, Tucumán, Argentina
| | - María Fernanda Pomares
- Instituto Superior de Investigaciones Biológicas (INSIBIO), CONICET-UNT and Instituto de Química Biológica “Dr. Bernabé Bloj”, Facultad de Bioquímica, Química y Farmacia, UNT. Chacabuco 461, T4000ILI -San Miguel de Tucumán, Tucumán, Argentina
| | - Paula A. Vincent
- Instituto Superior de Investigaciones Biológicas (INSIBIO), CONICET-UNT and Instituto de Química Biológica “Dr. Bernabé Bloj”, Facultad de Bioquímica, Química y Farmacia, UNT. Chacabuco 461, T4000ILI -San Miguel de Tucumán, Tucumán, Argentina
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Vicente CSL, Nascimento FX, Ikuyo Y, Cock PJA, Mota M, Hasegawa K. The genome and genetics of a high oxidative stress tolerant Serratia sp. LCN16 isolated from the plant parasitic nematode Bursaphelenchus xylophilus. BMC Genomics 2016; 17:301. [PMID: 27108223 PMCID: PMC4841953 DOI: 10.1186/s12864-016-2626-1] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2016] [Accepted: 04/16/2016] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Pine wilt disease (PWD) is a worldwide threat to pine forests, and is caused by the pine wood nematode (PWN) Bursaphelenchus xylophilus. Bacteria are known to be associated with PWN and may have an important role in PWD. Serratia sp. LCN16 is a PWN-associated bacterium, highly resistant to oxidative stress in vitro, and which beneficially contributes to the PWN survival under these conditions. Oxidative stress is generated as a part of the basal defense mechanism used by plants to combat pathogenic invasion. Here, we studied the biology of Serratia sp. LCN16 through genome analyses, and further investigated, using reverse genetics, the role of two genes directly involved in the neutralization of H2O2, namely the H2O2 transcriptional factor oxyR; and the H2O2-targeting enzyme, catalase katA. RESULTS Serratia sp. LCN16 is phylogenetically most closely related to the phytosphere group of Serratia, which includes S. proteamaculans, S. grimessi and S. liquefaciens. Likewise, Serratia sp. LCN16 shares many features with endophytes (plant-associated bacteria), such as genes coding for plant polymer degrading enzymes, iron uptake/transport, siderophore and phytohormone synthesis, aromatic compound degradation and detoxification enzymes. OxyR and KatA are directly involved in the high tolerance to H2O2 of Serratia sp. LCN16. Under oxidative stress, Serratia sp. LCN16 expresses katA independently of OxyR in contrast with katG which is under positive regulation of OxyR. Serratia sp. LCN16 mutants for oxyR (oxyR::int(614)) and katA (katA::int(808)) were sensitive to H2O2 in relation with wild-type, and both failed to protect the PWN from H2O2-stress exposure. Moreover, both mutants showed different phenotypes in terms of biofilm production and swimming/swarming behaviors. CONCLUSIONS This study provides new insights into the biology of PWN-associated bacteria Serratia sp. LCN16 and its extreme resistance to oxidative stress conditions, encouraging further research on the potential role of this bacterium in interaction with PWN in planta environment.
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Affiliation(s)
- Claudia S L Vicente
- NemaLab/ICAAM - Instituto de Ciências Agrárias e Ambientais Mediterrânicas, Departamento de Biologia, Universidade de Évora, Núcleo da Mitra, Ap. 94, 7002-554, Évora, Portugal.,Department of Environmental Biology, College of Bioscience & Biotechnology, Chubu University, 1200 Matsumoto, Kasugai, Aichi, 487-8501, Japan
| | - Francisco X Nascimento
- NemaLab/ICAAM - Instituto de Ciências Agrárias e Ambientais Mediterrânicas, Departamento de Biologia, Universidade de Évora, Núcleo da Mitra, Ap. 94, 7002-554, Évora, Portugal
| | - Yoriko Ikuyo
- Department of Environmental Biology, College of Bioscience & Biotechnology, Chubu University, 1200 Matsumoto, Kasugai, Aichi, 487-8501, Japan
| | - Peter J A Cock
- Information and Computational Sciences group (PJAC), The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK
| | - Manuel Mota
- NemaLab/ICAAM - Instituto de Ciências Agrárias e Ambientais Mediterrânicas, Departamento de Biologia, Universidade de Évora, Núcleo da Mitra, Ap. 94, 7002-554, Évora, Portugal.,Departamento de Ciências da Vida, Universidade Lusófona de Humanidades e Tecnologias, Lisboa, Portugal
| | - Koichi Hasegawa
- Department of Environmental Biology, College of Bioscience & Biotechnology, Chubu University, 1200 Matsumoto, Kasugai, Aichi, 487-8501, Japan.
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Aspergillus mulundensis sp. nov., a new species for the fungus producing the antifungal echinocandin lipopeptides, mulundocandins. J Antibiot (Tokyo) 2015; 69:141-8. [DOI: 10.1038/ja.2015.105] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2015] [Revised: 09/05/2015] [Accepted: 09/11/2015] [Indexed: 01/06/2023]
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Cary JW, Uka V, Han Z, Buyst D, Harris-Coward PY, Ehrlich KC, Wei Q, Bhatnagar D, Dowd PF, Martens SL, Calvo AM, Martins JC, Vanhaecke L, Coenye T, De Saeger S, Di Mavungu JD. An Aspergillus flavus secondary metabolic gene cluster containing a hybrid PKS–NRPS is necessary for synthesis of the 2-pyridones, leporins. Fungal Genet Biol 2015; 81:88-97. [DOI: 10.1016/j.fgb.2015.05.010] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2015] [Revised: 05/22/2015] [Accepted: 05/26/2015] [Indexed: 01/04/2023]
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Giuliano Garisto Donzelli B, Gibson DM, Krasnoff SB. Intracellular siderophore but not extracellular siderophore is required for full virulence in Metarhizium robertsii. Fungal Genet Biol 2015; 82:56-68. [PMID: 26135511 DOI: 10.1016/j.fgb.2015.06.008] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2015] [Revised: 06/26/2015] [Accepted: 06/27/2015] [Indexed: 10/23/2022]
Abstract
Efficient iron acquisition mechanisms are fundamental for microbial survival in the environment and for pathogen virulence within their hosts. M. robertsii produces two known iron-binding natural products: metachelins, which are used to scavenge extracellular iron, and ferricrocin, which is strictly intracellular. To study the contribution of siderophore-mediated iron uptake and storage to M. robertsii fitness, we generated null mutants for each siderophore synthase gene (mrsidD and mrsidC, respectively), as well as for the iron uptake transcriptional repressor mrsreA. All of these mutants showed impaired germination speed, differential sensitivity to hydrogen peroxide, and differential ability to overcome iron chelation on growth-limiting iron concentrations. RT-qPCR data supported regulation of mrsreA, mrsidC, and mrsidD by supplied iron in vitro and during growth within the insect host, Spodoptera exigua. We also observed strong upregulation of the insect iron-binding proteins, transferrins, during infection. Insect bioassays revealed that ferricrocin is required for full virulence against S. exigua; neither the loss of metachelin production nor the deletion of the transcription factor mrsreA significantly affected M. robertsii virulence.
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Affiliation(s)
- Bruno Giuliano Garisto Donzelli
- School of Integrative Plant Science - Plant Pathology and Plant-Microbe Biology Section, Cornell University, Ithaca, NY 14853, United States.
| | - Donna M Gibson
- USDA ARS, Robert W. Holley Center for Agriculture and Health, 538 Tower Road, Ithaca, NY 14853, United States
| | - Stuart B Krasnoff
- USDA ARS, Robert W. Holley Center for Agriculture and Health, 538 Tower Road, Ithaca, NY 14853, United States
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Brandon M, Howard B, Lawrence C, Laubenbacher R. Iron acquisition and oxidative stress response in aspergillus fumigatus. BMC SYSTEMS BIOLOGY 2015; 9:19. [PMID: 25908096 PMCID: PMC4418068 DOI: 10.1186/s12918-015-0163-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2014] [Accepted: 03/31/2015] [Indexed: 01/08/2023]
Abstract
BACKGROUND Aspergillus fumigatus is a ubiquitous airborne fungal pathogen that presents a life-threatening health risk to individuals with weakened immune systems. A. fumigatus pathogenicity depends on its ability to acquire iron from the host and to resist host-generated oxidative stress. Gaining a deeper understanding of the molecular mechanisms governing A. fumigatus iron acquisition and oxidative stress response may ultimately help to improve the diagnosis and treatment of invasive aspergillus infections. RESULTS This study follows a systems biology approach to investigate how adaptive behaviors emerge from molecular interactions underlying A. fumigatus iron regulation and oxidative stress response. We construct a Boolean network model from known interactions and simulate how changes in environmental iron and superoxide levels affect network dynamics. We propose rules for linking long term model behavior to qualitative estimates of cell growth and cell death. These rules are used to predict phenotypes of gene deletion strains. The model is validated on the basis of its ability to reproduce literature data not used in model generation. CONCLUSIONS The model reproduces gene expression patterns in experimental time course data when A. fumigatus is switched from a low iron to a high iron environment. In addition, the model is able to accurately represent the phenotypes of many knockout strains under varying iron and superoxide conditions. Model simulations support the hypothesis that intracellular iron regulates A. fumigatus transcription factors, SreA and HapX, by a post-translational, rather than transcriptional, mechanism. Finally, the model predicts that blocking siderophore-mediated iron uptake reduces resistance to oxidative stress. This indicates that combined targeting of siderophore-mediated iron uptake and the oxidative stress response network may act synergistically to increase fungal cell killing.
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Affiliation(s)
- Madison Brandon
- Center for Cell Analysis and Modeling, University of Connecticut Health Center, 400 Farmington Ave, Farmington, 06030, USA. .,Center for Quantitative Medicine, University of Connecticut Health Center, Farmington, 06030, USA.
| | - Brad Howard
- Department of Biological Sciences, Virginia Tech, 1405 Perry Street, Blacksburg, 24061, USA. .,Virginia Bioinformatics Institute, Virginia Tech, 1015 Life Science Circle, Blacksburg, 24061, US.
| | - Christopher Lawrence
- Department of Biological Sciences, Virginia Tech, 1405 Perry Street, Blacksburg, 24061, USA. .,Virginia Bioinformatics Institute, Virginia Tech, 1015 Life Science Circle, Blacksburg, 24061, US.
| | - Reinhard Laubenbacher
- Center for Quantitative Medicine, University of Connecticut Health Center, Farmington, 06030, USA. .,The Jackson Laboratory for Genomic Medicine, 10 Discovery Drive, Farmington, 06030, USA. .,Department of Cell Biology, University of Connecticut Health Center, 263 Farmington Ave, Farmington, 06030, USA.
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50
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Becker K, Beer C, Freitag M, Kück U. Genome-wide identification of target genes of a mating-type α-domain transcription factor reveals functions beyond sexual development. Mol Microbiol 2015; 96:1002-22. [DOI: 10.1111/mmi.12987] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/26/2015] [Indexed: 12/21/2022]
Affiliation(s)
- Kordula Becker
- Christian Doppler Laboratory for Fungal Biotechnology; Lehrstuhl für Allgemeine und Molekulare Botanik; Ruhr-Universität Bochum; Universitätsstr. 150 D-44780 Bochum Germany
| | - Christina Beer
- Christian Doppler Laboratory for Fungal Biotechnology; Lehrstuhl für Allgemeine und Molekulare Botanik; Ruhr-Universität Bochum; Universitätsstr. 150 D-44780 Bochum Germany
| | - Michael Freitag
- Department of Biochemistry and Biophysics; Oregon State University; Corvallis Oregon 97331-7305 USA
| | - Ulrich Kück
- Christian Doppler Laboratory for Fungal Biotechnology; Lehrstuhl für Allgemeine und Molekulare Botanik; Ruhr-Universität Bochum; Universitätsstr. 150 D-44780 Bochum Germany
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