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Liu F, Zeng M, Zhou X, Huang F, Song Z. Aspergillus fumigatus escape mechanisms from its harsh survival environments. Appl Microbiol Biotechnol 2024; 108:53. [PMID: 38175242 DOI: 10.1007/s00253-023-12952-z] [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: 08/15/2023] [Revised: 10/09/2023] [Accepted: 10/19/2023] [Indexed: 01/05/2024]
Abstract
Aspergillus fumigatus is a ubiquitous pathogenic mold and causes several diseases, including mycotoxicosis, allergic reactions, and systemic diseases (invasive aspergillosis), with high mortality rates. In its ecological niche, the fungus has evolved and mastered many reply strategies to resist and survive against negative threats, including harsh environmental stress and deficiency of essential nutrients from natural environments, immunity responses and drug treatments in host, and competition from symbiotic microorganisms. Hence, treating A. fumigatus infection is a growing challenge. In this review, we summarized A. fumigatus reply strategies and escape mechanisms and clarified the main competitive or symbiotic relationships between A. fumigatus, viruses, bacteria, or fungi in host microecology. Additionally, we discussed the contemporary drug repertoire used to treat A. fumigatus and the latest evidence of potential resistance mechanisms. This review provides valuable knowledge which will stimulate further investigations and clinical applications for treating and preventing A. fumigatus infections. KEY POINTS: • Harsh living environment was a great challenge for A. fumigatus survival. • A. fumigatus has evolved multiple strategies to escape host immune responses. • A. fumigatus withstands antifungal drugs via intrinsic escape mechanisms.
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Affiliation(s)
- Fangyan Liu
- School of Basic Medical Sciences, Southwest Medical University, Luzhou, 646000, People's Republic of China
| | - Meng Zeng
- School of Basic Medical Sciences, Southwest Medical University, Luzhou, 646000, People's Republic of China
- Department of Clinical Laboratory, Yongchuan Hospital of Chongqing Medical University, Chongqing, 402160, People's Republic of China
| | - Xue Zhou
- School of Basic Medical Sciences, Southwest Medical University, Luzhou, 646000, People's Republic of China
| | - Fujiao Huang
- School of Basic Medical Sciences, Southwest Medical University, Luzhou, 646000, People's Republic of China
| | - Zhangyong Song
- School of Basic Medical Sciences, Southwest Medical University, Luzhou, 646000, People's Republic of China.
- Molecular Biotechnology Platform, Public Center of Experimental Technology, Southwest Medical University, Luzhou, 646000, People's Republic of China.
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2
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Seo HW, Wassano NS, Amir Rawa MS, Nickles GR, Damasio A, Keller NP. A Timeline of Biosynthetic Gene Cluster Discovery in Aspergillus fumigatus: From Characterization to Future Perspectives. J Fungi (Basel) 2024; 10:266. [PMID: 38667937 PMCID: PMC11051388 DOI: 10.3390/jof10040266] [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: 03/08/2024] [Revised: 03/27/2024] [Accepted: 03/28/2024] [Indexed: 04/28/2024] Open
Abstract
In 1999, the first biosynthetic gene cluster (BGC), synthesizing the virulence factor DHN melanin, was characterized in Aspergillus fumigatus. Since then, 19 additional BGCs have been linked to specific secondary metabolites (SMs) in this species. Here, we provide a comprehensive timeline of A. fumigatus BGC discovery and find that initial advances centered around the commonly expressed SMs where chemical structure informed rationale identification of the producing BGC (e.g., gliotoxin, fumigaclavine, fumitremorgin, pseurotin A, helvolic acid, fumiquinazoline). Further advances followed the transcriptional profiling of a ΔlaeA mutant, which aided in the identification of endocrocin, fumagillin, hexadehydroastechrome, trypacidin, and fumisoquin BGCs. These SMs and their precursors are the commonly produced metabolites in most A. fumigatus studies. Characterization of other BGC/SM pairs required additional efforts, such as induction treatments, including co-culture with bacteria (fumicycline/neosartoricin, fumigermin) or growth under copper starvation (fumivaline, fumicicolin). Finally, four BGC/SM pairs were discovered via overexpression technologies, including the use of heterologous hosts (fumicycline/neosartoricin, fumihopaside, sphingofungin, and sartorypyrone). Initial analysis of the two most studied A. fumigatus isolates, Af293 and A1160, suggested that both harbored ca. 34-36 BGCs. However, an examination of 264 available genomes of A. fumigatus shows up to 20 additional BGCs, with some strains showing considerable variations in BGC number and composition. These new BGCs present a new frontier in the future of secondary metabolism characterization in this important species.
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Affiliation(s)
- Hye-Won Seo
- Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, WI 53706, USA; (H.-W.S.); (N.S.W.); (M.S.A.R.); (G.R.N.)
| | - Natalia S. Wassano
- Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, WI 53706, USA; (H.-W.S.); (N.S.W.); (M.S.A.R.); (G.R.N.)
- Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas (UNICAMP), São Paulo 13083-970, Brazil;
| | - Mira Syahfriena Amir Rawa
- Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, WI 53706, USA; (H.-W.S.); (N.S.W.); (M.S.A.R.); (G.R.N.)
| | - Grant R. Nickles
- Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, WI 53706, USA; (H.-W.S.); (N.S.W.); (M.S.A.R.); (G.R.N.)
| | - André Damasio
- Department of Biochemistry and Tissue Biology, Institute of Biology, University of Campinas (UNICAMP), São Paulo 13083-970, Brazil;
| | - Nancy P. Keller
- Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, WI 53706, USA; (H.-W.S.); (N.S.W.); (M.S.A.R.); (G.R.N.)
- Department of Plant Pathology, University of Wisconsin, Madison, WI 53706, USA
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3
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Alves de Castro P, Figueiredo Pinzan C, Dos Reis TF, Valero C, Van Rhijn N, Menegatti C, de Freitas Migliorini IL, Bromley M, Fleming AB, Traynor AM, Sarikaya-Bayram Ö, Bayram Ö, Malavazi I, Ebel F, Barbosa JCJ, Fill T, Pupo MT, Goldman GH. Aspergillus fumigatus mitogen-activated protein kinase MpkA is involved in gliotoxin production and self-protection. Nat Commun 2024; 15:33. [PMID: 38167253 PMCID: PMC10762094 DOI: 10.1038/s41467-023-44329-1] [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: 05/22/2023] [Accepted: 12/08/2023] [Indexed: 01/05/2024] Open
Abstract
Aspergillus fumigatus is a saprophytic fungus that can cause a variety of human diseases known as aspergillosis. Mycotoxin gliotoxin (GT) production is important for its virulence and must be tightly regulated to avoid excess production and toxicity to the fungus. GT self-protection by GliT oxidoreductase and GtmA methyltransferase activities is related to the subcellular localization of these enzymes and how GT can be sequestered from the cytoplasm to avoid increased cell damage. Here, we show that GliT:GFP and GtmA:GFP are localized in the cytoplasm and in vacuoles during GT production. The Mitogen-Activated Protein kinase MpkA is essential for GT production and self-protection, interacts physically with GliT and GtmA and it is necessary for their regulation and subsequent presence in the vacuoles. The sensor histidine kinase SlnASln1 is important for modulation of MpkA phosphorylation. Our work emphasizes the importance of MpkA and compartmentalization of cellular events for GT production and self-defense.
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Affiliation(s)
- Patrícia Alves de Castro
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Camila Figueiredo Pinzan
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Thaila Fernanda Dos Reis
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Clara Valero
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
- Manchester Fungal Infection Group, Division of Evolution, Infection and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Norman Van Rhijn
- Manchester Fungal Infection Group, Division of Evolution, Infection and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Carla Menegatti
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | | | - Michael Bromley
- Manchester Fungal Infection Group, Division of Evolution, Infection and Genomic Sciences, School of Biological Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Alastair B Fleming
- Department of Microbiology, Moyne Institute of Preventive Medicine, Trinity College Dublin, Dublin, Ireland
| | - Aimee M Traynor
- Department of Biology, Maynooth University, Maynooth, Co. Kildare, Ireland
| | | | - Özgür Bayram
- Department of Biology, Maynooth University, Maynooth, Co. Kildare, Ireland.
| | - Iran Malavazi
- Departamento de Genética e Evolução, Centro de Ciências Biológicas e da Saúde, Universidade Federal de São Carlos, São Carlos, São Paulo, Brazil
| | - Frank Ebel
- Institut für Infektionsmedizin und Zoonosen, Medizinische Fakultät, LMU, 80539, München, Germany
| | | | - Taícia Fill
- Instituto de Química, Universidade Estadual de Campinas, Campinas, Brazil
| | - Monica Tallarico Pupo
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Gustavo H Goldman
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil.
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Lin SY, Oakley CE, Jenkinson CB, Chiang YM, Lee CK, Jones CG, Seidler PM, Nelson HM, Todd RB, Wang CCC, Oakley BR. A heterologous expression platform in Aspergillus nidulans for the elucidation of cryptic secondary metabolism biosynthetic gene clusters: discovery of the Aspergillus fumigatus sartorypyrone biosynthetic pathway. Chem Sci 2023; 14:11022-11032. [PMID: 37860661 PMCID: PMC10583710 DOI: 10.1039/d3sc02226a] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2023] [Accepted: 06/26/2023] [Indexed: 10/21/2023] Open
Abstract
Aspergillus fumigatus is a serious human pathogen causing life-threatening Aspergillosis in immunocompromised patients. Secondary metabolites (SMs) play an important role in pathogenesis, but the products of many SM biosynthetic gene clusters (BGCs) remain unknown. In this study, we have developed a heterologous expression platform in Aspergillus nidulans, using a newly created genetic dereplication strain, to express a previously unknown BGC from A. fumigatus and determine its products. The BGC produces sartorypyrones, and we have named it the spy BGC. Analysis of targeted gene deletions by HRESIMS, NMR, and microcrystal electron diffraction (MicroED) enabled us to identify 12 products from the spy BGC. Seven of the compounds have not been isolated previously. We also individually expressed the polyketide synthase (PKS) gene spyA and demonstrated that it produces the polyketide triacetic acid lactone (TAL), a potentially important biorenewable platform chemical. Our data have allowed us to propose a biosynthetic pathway for sartorypyrones and related natural products. This work highlights the potential of using the A. nidulans heterologous expression platform to uncover cryptic BGCs from A. fumigatus and other species, despite the complexity of their secondary metabolomes.
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Affiliation(s)
- Shu-Yi Lin
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California Los Angeles CA 90089 USA
| | - C Elizabeth Oakley
- Department of Molecular Biosciences, University of Kansas 1200 Sunnyside Avenue Lawrence KS 66045 USA
| | - Cory B Jenkinson
- Department of Molecular Biosciences, University of Kansas 1200 Sunnyside Avenue Lawrence KS 66045 USA
| | - Yi-Ming Chiang
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California Los Angeles CA 90089 USA
| | - Ching-Kuo Lee
- School of Pharmacy, College of Pharmacy, Taipei Medical University Taipei 11031 Taiwan
| | - Christopher G Jones
- The Arnold and Mabel Beckman Laboratory of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology Pasadena California 91125 USA
| | - Paul M Seidler
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California Los Angeles CA 90089 USA
| | - Hosea M Nelson
- The Arnold and Mabel Beckman Laboratory of Chemical Synthesis, Division of Chemistry and Chemical Engineering, California Institute of Technology Pasadena California 91125 USA
| | - Richard B Todd
- Department of Plant Pathology, Kansas State University Manhattan KS 66506 USA
| | - Clay C C Wang
- Department of Pharmacology and Pharmaceutical Sciences, University of Southern California Los Angeles CA 90089 USA
- Department of Chemistry, University of Southern California Los Angeles CA 90089 USA
| | - Berl R Oakley
- Department of Molecular Biosciences, University of Kansas 1200 Sunnyside Avenue Lawrence KS 66045 USA
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Paul S, Stamnes MA, Moye-Rowley WS. Interactions between the transcription factors FfmA and AtrR are required to properly regulate gene expression in the fungus Aspergillus fumigatus. G3 (BETHESDA, MD.) 2023; 13:jkad173. [PMID: 37523774 PMCID: PMC10542180 DOI: 10.1093/g3journal/jkad173] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2023] [Revised: 06/05/2023] [Accepted: 07/17/2023] [Indexed: 08/02/2023]
Abstract
Transcriptional regulation of azole resistance in the filamentous fungus Aspergillus fumigatus is a key step in development of this problematic clinical phenotype. We and others have previously described a C2H2-containing transcription factor called FfmA that is required for normal levels of voriconazole susceptibility. Null alleles of ffmA exhibit a strongly compromised growth rate even in the absence of any external stress. Here, we employ an acutely repressible doxycycline-off form of ffmA to rapidly deplete FfmA protein from the cell. Using this approach, we carried out RNA-seq analyses to probe the transcriptome cells acutely deprived of FfmA. A total of 2,000 genes were differentially expressed upon acute depletion of FfmA, illustrating the broad transcriptomic effect of this factor. Interestingly, the transcriptome changes observed upon this acute depletion of FfmA expression only shared limited overlap with those found in an ffmAΔ null strain analyzed by others. Chromatin immunoprecipitation coupled with high throughput DNA sequencing analysis (ChIP-seq) identified 530 genes that were bound by FfmA. More than 300 of these genes were also bound by AtrR, a transcription factor important in azole drug resistance, demonstrating striking regulatory overlap with FfmA. However, while AtrR is an upstream activation protein with known specificity, our data suggest that FfmA is a chromatin-associated factor that binds DNA in a manner dependent on other factors. We provide evidence that AtrR and FfmA interact in the cell and show reciprocal expression modulation. Interaction of AtrR and FfmA is required for normal gene expression in A. fumigatus.
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Affiliation(s)
- Sanjoy Paul
- Department of Molecular Physiology and Biophysics, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - Mark A Stamnes
- Department of Molecular Physiology and Biophysics, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - W Scott Moye-Rowley
- Department of Molecular Physiology and Biophysics, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
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6
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Chen Y, Yang X, Zhang L, Wu Q, Li S, Gou J, He J, Zhang K, Li S, Niu X. Tryptophan-centered metabolic alterations coincides with lipid-mediated fungal response to cold stress. Heliyon 2023; 9:e13066. [PMID: 36747564 PMCID: PMC9898655 DOI: 10.1016/j.heliyon.2023.e13066] [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: 06/02/2022] [Revised: 01/12/2023] [Accepted: 01/15/2023] [Indexed: 01/22/2023] Open
Abstract
Tryptophan and its derived metabolites have been assumed to play important roles in the development and survival of organisms. However, the links of tryptophan and its derived metabolites to temperature change remained largely cryptic. Here we presented that a class of prenyl indole alkaloids biosynthesized from tryptophan dramatically accumulated in thermophilic fungus Thermomyces dupontii under cold stress, in which lipid droplets were also highly accumulated and whose conidiophores were highly build-up. Concurrently, disruption of the key NRPS gene involved in the biosynthesis of prenyl indole alkaloids, resulted in decreased lipid and shrunken mitochondria but enlarged vacuoles. Moreover, the Fe3+ and superoxide levels in ΔNRPS were significantly increased but the reactive oxygen species lipid peroxidation and autophagy levels decreased. Metabolomics study revealed that most enriched metabolites in ΔNRPS were mainly composed of tryptophan degraded metabolites including well known ROS scavenger kynurenamines, and lipid-inhibitors, anthranilic acid and indoleacetic acid, and free radical reaction suppressor free fatty acids. Transcriptomic analysis suggested that the key gene involved in tryptophan metabolism, coinciding with the lipid metabolic processes and ion transports were most up-regulated in ΔNRPS under stress. Our results confirmed a lipid-mediated fungal response to cold stress and unveiled a link of tryptophan-based metabolic reprogramming to the fungal cold adaption.
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Affiliation(s)
- Yonghong Chen
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan University, Kunming 650032, China
| | - Xiaoyu Yang
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan University, Kunming 650032, China
| | - Longlong Zhang
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan University, Kunming 650032, China
| | - Qunfu Wu
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan University, Kunming 650032, China
| | - Shuhong Li
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan University, Kunming 650032, China
| | - Jianghui Gou
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan University, Kunming 650032, China
| | - Jiangbo He
- Kunming Key Laboratory of Respiratory Disease, Kunming University, Kunming 650214, China
| | - Keqin Zhang
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan University, Kunming 650032, China
| | - Shenghong Li
- State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650204, China
- Corresponding author.
| | - Xuemei Niu
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan University, Kunming 650032, China
- Corresponding author.
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7
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Pseudokinase NRP1 facilitates endocytosis of transferrin in the African trypanosome. Sci Rep 2022; 12:18572. [PMID: 36329148 PMCID: PMC9633767 DOI: 10.1038/s41598-022-22054-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2022] [Accepted: 10/10/2022] [Indexed: 11/06/2022] Open
Abstract
Trypanosoma brucei causes human African trypanosomiasis (HAT) and nagana in cattle. During infection of a vertebrate, endocytosis of host transferrin (Tf) is important for viability of the parasite. The majority of proteins involved in trypanosome endocytosis of Tf are unknown. Here we identify pseudokinase NRP1 (Tb427tmp.160.4770) as a regulator of Tf endocytosis. Genetic knockdown of NRP1 inhibited endocytosis of Tf without blocking uptake of bovine serum albumin. Binding of Tf to the flagellar pocket was not affected by knockdown of NRP1. However the quantity of Tf per endosome dropped significantly, consistent with NRP1 promoting robust capture and/or retention of Tf in vesicles. NRP1 is involved in motility of Tf-laden vesicles since distances between endosomes and the kinetoplast were reduced after knockdown of the gene. In search of possible mediators of NRP1 modulation of Tf endocytosis, the gene was knocked down and the phosphoproteome analyzed. Phosphorylation of protein kinases forkhead, NEK6, and MAPK10 was altered, in addition to EpsinR, synaptobrevin and other vesicle-associated proteins predicted to be involved in endocytosis. These candidate proteins may link NRP1 functionally either to protein kinases or to vesicle-associated proteins.
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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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de Castro PA, Colabardini AC, Moraes M, Horta MAC, Knowles SL, Raja HA, Oberlies NH, Koyama Y, Ogawa M, Gomi K, Steenwyk JL, Rokas A, Gonçales RA, Duarte-Oliveira C, Carvalho A, Ries LNA, Goldman GH. Regulation of gliotoxin biosynthesis and protection in Aspergillus species. PLoS Genet 2022; 18:e1009965. [PMID: 35041649 PMCID: PMC8797188 DOI: 10.1371/journal.pgen.1009965] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 01/28/2022] [Accepted: 01/04/2022] [Indexed: 02/07/2023] Open
Abstract
Aspergillus fumigatus causes a range of human and animal diseases collectively known as aspergillosis. A. fumigatus possesses and expresses a range of genetic determinants of virulence, which facilitate colonisation and disease progression, including the secretion of mycotoxins. Gliotoxin (GT) is the best studied A. fumigatus mycotoxin with a wide range of known toxic effects that impair human immune cell function. GT is also highly toxic to A. fumigatus and this fungus has evolved self-protection mechanisms that include (i) the GT efflux pump GliA, (ii) the GT neutralising enzyme GliT, and (iii) the negative regulation of GT biosynthesis by the bis-thiomethyltransferase GtmA. The transcription factor (TF) RglT is the main regulator of GliT and this GT protection mechanism also occurs in the non-GT producing fungus A. nidulans. However, the A. nidulans genome does not encode GtmA and GliA. This work aimed at analysing the transcriptional response to exogenous GT in A. fumigatus and A. nidulans, two distantly related Aspergillus species, and to identify additional components required for GT protection. RNA-sequencing shows a highly different transcriptional response to exogenous GT with the RglT-dependent regulon also significantly differing between A. fumigatus and A. nidulans. However, we were able to observe homologs whose expression pattern was similar in both species (43 RglT-independent and 11 RglT-dependent). Based on this approach, we identified a novel RglT-dependent methyltranferase, MtrA, involved in GT protection. Taking into consideration the occurrence of RglT-independent modulated genes, we screened an A. fumigatus deletion library of 484 transcription factors (TFs) for sensitivity to GT and identified 15 TFs important for GT self-protection. Of these, the TF KojR, which is essential for kojic acid biosynthesis in Aspergillus oryzae, was also essential for virulence and GT biosynthesis in A. fumigatus, and for GT protection in A. fumigatus, A. nidulans, and A. oryzae. KojR regulates rglT, gliT, gliJ expression and sulfur metabolism in Aspergillus species. Together, this study identified conserved components required for GT protection in Aspergillus species. A. fumigatus secretes mycotoxins that are essential for its virulence and pathogenicity. Gliotoxin (GT) is a sulfur-containing mycotoxin, which is known to impair several aspects of the human immune response. GT is also toxic to different fungal species, which have evolved several GT protection strategies. To further decipher these responses, we used transcriptional profiling aiming to compare the response to GT in the GT producer A. fumigatus and the GT non-producer A. nidulans. This analysis allowed us to identify additional genes with a potential role in GT protection. We also identified 15 transcription factors (TFs) encoded in the A. fumigatus genome that are important for conferring resistance to exogenous gliotoxin. One of these TFs, KojR, which is essential for A. oryzae kojic acid production, is also important for virulence in A. fumigatus and GT protection in A. fumigatus, A. nidulans and A. oryzae. KojR regulates the expression of genes important for gliotoxin biosynthesis and protection, and sulfur metabolism. Together, this work identified conserved components required for gliotoxin protection in Aspergillus species.
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Affiliation(s)
- Patrícia Alves de Castro
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Ana Cristina Colabardini
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Maísa Moraes
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | | | - Sonja L. Knowles
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, North Carolina United States of America
| | - Huzefa A. Raja
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, North Carolina United States of America
| | - Nicholas H. Oberlies
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, North Carolina United States of America
| | - Yasuji Koyama
- Noda Institute for Scientific Research, 338 Noda, Chiba, Japan
| | - Masahiro Ogawa
- Noda Institute for Scientific Research, 338 Noda, Chiba, Japan
| | - Katsuya Gomi
- Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, Sendai, Japan
| | - Jacob L. Steenwyk
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Antonis Rokas
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, United States of America
| | - Relber A. Gonçales
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal
- ICVS/3B’s—PT Government Associate Laboratory, Guimarães/Braga, Portugal
| | - Cláudio Duarte-Oliveira
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal
- ICVS/3B’s—PT Government Associate Laboratory, Guimarães/Braga, Portugal
| | - Agostinho Carvalho
- Life and Health Sciences Research Institute (ICVS), School of Medicine, University of Minho, Braga, Portugal
- ICVS/3B’s—PT Government Associate Laboratory, Guimarães/Braga, Portugal
| | - Laure N. A. Ries
- MRC Centre for Medical Mycology at the University of Exeter, Geoffrey Pope Building, Exeter, United Kingdom
- * E-mail: (LNAR); (GHG)
| | - Gustavo H. Goldman
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
- * E-mail: (LNAR); (GHG)
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10
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Colabardini AC, Wang F, Miao Z, Pardeshi L, Valero C, de Castro PA, Akiyama DY, Tan K, Nora LC, Silva-Rocha R, Marcet-Houben M, Gabaldón T, Fill T, Wong KH, Goldman GH. Chromatin profiling reveals heterogeneity in clinical isolates of the human pathogen Aspergillus fumigatus. PLoS Genet 2022; 18:e1010001. [PMID: 35007279 PMCID: PMC8782537 DOI: 10.1371/journal.pgen.1010001] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Revised: 01/21/2022] [Accepted: 12/17/2021] [Indexed: 12/21/2022] Open
Abstract
Invasive Pulmonary Aspergillosis, which is caused by the filamentous fungus Aspergillus fumigatus, is a life-threatening infection for immunosuppressed patients. Chromatin structure regulation is important for genome stability maintenance and has the potential to drive genome rearrangements and affect virulence and pathogenesis of pathogens. Here, we performed the first A. fumigatus global chromatin profiling of two histone modifications, H3K4me3 and H3K9me3, focusing on the two most investigated A. fumigatus clinical isolates, Af293 and CEA17. In eukaryotes, H3K4me3 is associated with active transcription, while H3K9me3 often marks silent genes, DNA repeats, and transposons. We found that H3K4me3 deposition is similar between the two isolates, while H3K9me3 is more variable and does not always represent transcriptional silencing. Our work uncovered striking differences in the number, locations, and expression of transposable elements between Af293 and CEA17, and the differences are correlated with H3K9me3 modifications and higher genomic variations among strains of Af293 background. Moreover, we further showed that the Af293 strains from different laboratories actually differ in their genome contents and found a frequently lost region in chromosome VIII. For one such Af293 variant, we identified the chromosomal changes and demonstrated their impacts on its secondary metabolites production, growth and virulence. Overall, our findings not only emphasize the influence of genome heterogeneity on A. fumigatus fitness, but also caution about unnoticed chromosomal variations among common laboratory strains.
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Affiliation(s)
- Ana Cristina Colabardini
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brazil
- Faculty of Health Sciences, University of Macau, Macau SAR of China
| | - Fang Wang
- Faculty of Health Sciences, University of Macau, Macau SAR of China
- Intensive Care Unit, Biomedical Research Center, Shenzhen Institute of Translational Medicine, Shenzhen Second People’s Hospital, The First Affiliated Hospital of Shenzhen University, Shenzhen, China
| | - Zhengqiang Miao
- Faculty of Health Sciences, University of Macau, Macau SAR of China
| | - Lakhansing Pardeshi
- Faculty of Health Sciences, University of Macau, Macau SAR of China
- Genomics, Bioinformatics and Single Cell Analysis Core, Faculty of Health Sciences, University of Macau, Macau SAR of China
| | - Clara Valero
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Patrícia Alves de Castro
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Daniel Yuri Akiyama
- Instituto de Química, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
| | - Kaeling Tan
- Faculty of Health Sciences, University of Macau, Macau SAR of China
- Genomics, Bioinformatics and Single Cell Analysis Core, Faculty of Health Sciences, University of Macau, Macau SAR of China
| | - Luisa Czamanski Nora
- Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Rafael Silva-Rocha
- Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brazil
| | - Marina Marcet-Houben
- Barcelona Supercomputing Centre (BSC-CNS). Jordi Girona, Barcelona, Spain
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac, Barcelona, Spain
| | - Toni Gabaldón
- Barcelona Supercomputing Centre (BSC-CNS). Jordi Girona, Barcelona, Spain
- Institute for Research in Biomedicine (IRB Barcelona), The Barcelona Institute of Science and Technology, Baldiri Reixac, Barcelona, Spain
- Catalan Institution for Research and Advanced Studies (ICREA), Barcelona, Spain
| | - Taicia Fill
- Instituto de Química, Universidade Estadual de Campinas, Campinas, São Paulo, Brazil
| | - Koon Ho Wong
- Faculty of Health Sciences, University of Macau, Macau SAR of China
- Institute of Translational Medicine, Faculty of Health Sciences, University of Macau, Macau SAR of China
- MoE Frontiers Science Center for Precision Oncology, University of Macau, Macau SAR of China
| | - Gustavo H. Goldman
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, São Paulo, Brazil
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11
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Steenwyk JL, Mead ME, de Castro PA, Valero C, Damasio A, dos Santos RAC, Labella AL, Li Y, Knowles SL, Raja HA, Oberlies NH, Zhou X, Cornely OA, Fuchs F, Koehler P, Goldman GH, Rokas A. Genomic and Phenotypic Analysis of COVID-19-Associated Pulmonary Aspergillosis Isolates of Aspergillus fumigatus. Microbiol Spectr 2021; 9:e0001021. [PMID: 34106569 PMCID: PMC8552514 DOI: 10.1128/spectrum.00010-21] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Accepted: 04/08/2021] [Indexed: 02/06/2023] Open
Abstract
The ongoing global pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for coronavirus disease 2019 (COVID-19), first described in Wuhan, China. A subset of COVID-19 patients has been reported to have acquired secondary infections by microbial pathogens, such as opportunistic fungal pathogens from the genus Aspergillus. To gain insight into COVID-19-associated pulmonary aspergillosis (CAPA), we analyzed the genomes and characterized the phenotypic profiles of four CAPA isolates of Aspergillus fumigatus obtained from patients treated in the area of North Rhine-Westphalia, Germany. By examining the mutational spectrum of single nucleotide polymorphisms, insertion-deletion polymorphisms, and copy number variants among 206 genes known to modulate A. fumigatus virulence, we found that CAPA isolate genomes do not exhibit significant differences from the genome of the Af293 reference strain. By examining a number of factors, including virulence in an invertebrate moth model, growth in the presence of osmotic, cell wall, and oxidative stressors, secondary metabolite biosynthesis, and the MIC of antifungal drugs, we found that CAPA isolates were generally, but not always, similar to A. fumigatus reference strains Af293 and CEA17. Notably, CAPA isolate D had more putative loss-of-function mutations in genes known to increase virulence when deleted. Moreover, CAPA isolate D was significantly more virulent than the other three CAPA isolates and the A. fumigatus reference strains Af293 and CEA17, but similarly virulent to two other clinical strains of A. fumigatus. These findings expand our understanding of the genomic and phenotypic characteristics of isolates that cause CAPA. IMPORTANCE The global pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the etiological agent of coronavirus disease 2019 (COVID-19), has already killed millions of people. COVID-19 patient outcome can be further complicated by secondary infections, such as COVID-19-associated pulmonary aspergillosis (CAPA). CAPA is caused by Aspergillus fungal pathogens, but there is little information about the genomic and phenotypic characteristics of CAPA isolates. We conducted genome sequencing and extensive phenotyping of four CAPA isolates of Aspergillus fumigatus from Germany. We found that CAPA isolates were often, but not always, similar to other reference strains of A. fumigatus across 206 genetic determinants of infection-relevant phenotypes, including virulence. For example, CAPA isolate D was more virulent than other CAPA isolates and reference strains in an invertebrate model of fungal disease, but similarly virulent to two other clinical strains. These results expand our understanding of COVID-19-associated pulmonary aspergillosis.
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Affiliation(s)
- Jacob L. Steenwyk
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA
| | - Matthew E. Mead
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA
| | - Patrícia Alves de Castro
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Clara Valero
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - André Damasio
- Institute of Biology, University of Campinas (UNICAMP), Campinas-SP, Brazil
- Experimental Medicine Research Cluster (EMRC), University of Campinas (UNICAMP), Campinas-SP, Brazil
| | - Renato A. C. dos Santos
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Abigail L. Labella
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA
| | - Yuanning Li
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA
| | - Sonja L. Knowles
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, Greensboro, North Carolina, USA
| | - Huzefa A. Raja
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, Greensboro, North Carolina, USA
| | - Nicholas H. Oberlies
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, Greensboro, North Carolina, USA
| | - Xiaofan Zhou
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
| | - Oliver A. Cornely
- University of Cologne, Medical Faculty and University Hospital Cologne, Department I of Internal Medicine, Excellence Center for Medical Mycology (ECMM), Cologne, Germany
- University of Cologne, Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Cologne, Germany
- ZKS Köln, Clinical Trials Centre Cologne, Cologne, Germany
- German Center for Infection Research (DZIF), Partner Site Bonn‐Cologne, Medical Faculty and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Frieder Fuchs
- Faculty of Medicine, Institute for Medical Microbiology, Immunology and Hygiene, University of Cologne, Cologne, Germany
| | - Philipp Koehler
- University of Cologne, Medical Faculty and University Hospital Cologne, Department I of Internal Medicine, Excellence Center for Medical Mycology (ECMM), Cologne, Germany
- University of Cologne, Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Cologne, Germany
| | - Gustavo H. Goldman
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Antonis Rokas
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA
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12
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Dual-purpose isocyanides produced by Aspergillus fumigatus contribute to cellular copper sufficiency and exhibit antimicrobial activity. Proc Natl Acad Sci U S A 2021; 118:2015224118. [PMID: 33593906 DOI: 10.1073/pnas.2015224118] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
Abstract
The maintenance of sufficient but nontoxic pools of metal micronutrients is accomplished through diverse homeostasis mechanisms in fungi. Siderophores play a well established role for iron homeostasis; however, no copper-binding analogs have been found in fungi. Here we demonstrate that, in Aspergillus fumigatus, xanthocillin and other isocyanides derived from the xan biosynthetic gene cluster (BGC) bind copper, impact cellular copper content, and have significant metal-dependent antimicrobial properties. xan BGC-derived isocyanides are secreted and bind copper as visualized by a chrome azurol S (CAS) assay, and inductively coupled plasma mass spectrometry analysis of A. fumigatus intracellular copper pools demonstrated a role for xan cluster metabolites in the accumulation of copper. A. fumigatus coculture with a variety of human pathogenic fungi and bacteria established copper-dependent antimicrobial properties of xan BGC metabolites, including inhibition of laccase activity. Remediation of xanthocillin-treated Pseudomonas aeruginosa growth by copper supported the copper-chelating properties of xan BGC isocyanide products. The existence of the xan BGC in several filamentous fungi suggests a heretofore unknown role of eukaryotic natural products in copper homeostasis and mediation of interactions with competing microbes.
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13
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Boysen JM, Saeed N, Hillmann F. Natural products in the predatory defence of the filamentous fungal pathogen Aspergillus fumigatus. Beilstein J Org Chem 2021; 17:1814-1827. [PMID: 34394757 PMCID: PMC8336654 DOI: 10.3762/bjoc.17.124] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 07/14/2021] [Indexed: 11/30/2022] Open
Abstract
The kingdom of fungi comprises a large and highly diverse group of organisms that thrive in diverse natural environments. One factor to successfully confront challenges in their natural habitats is the capability to synthesize defensive secondary metabolites. The genetic potential for the production of secondary metabolites in fungi is high and numerous potential secondary metabolite gene clusters have been identified in sequenced fungal genomes. Their production may well be regulated by specific ecological conditions, such as the presence of microbial competitors, symbionts or predators. Here we exemplarily summarize our current knowledge on identified secondary metabolites of the pathogenic fungus Aspergillus fumigatus and their defensive function against (microbial) predators.
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Affiliation(s)
- Jana M Boysen
- Junior Research Group Evolution of Microbial Interactions, Leibniz-Institute for Natural Product Research and Infection Biology – Hans Knöll Institute (HKI), Beutenbergstr. 11a, 07745 Jena, Germany
- Institute of Microbiology, Friedrich Schiller University Jena, Jena, Germany
| | - Nauman Saeed
- Junior Research Group Evolution of Microbial Interactions, Leibniz-Institute for Natural Product Research and Infection Biology – Hans Knöll Institute (HKI), Beutenbergstr. 11a, 07745 Jena, Germany
- Institute of Microbiology, Friedrich Schiller University Jena, Jena, Germany
| | - Falk Hillmann
- Junior Research Group Evolution of Microbial Interactions, Leibniz-Institute for Natural Product Research and Infection Biology – Hans Knöll Institute (HKI), Beutenbergstr. 11a, 07745 Jena, Germany
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14
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Urquhart AS, Elliott CE, Zeng W, Idnurm A. Constitutive expression of transcription factor SirZ blocks pathogenicity in Leptosphaeria maculans independently of sirodesmin production. PLoS One 2021; 16:e0252333. [PMID: 34111151 PMCID: PMC8191991 DOI: 10.1371/journal.pone.0252333] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Accepted: 05/14/2021] [Indexed: 11/28/2022] Open
Abstract
Sirodesmin, the major secondary metabolite produced by the plant pathogenic fungus Leptosphaeria maculans in vitro, has been linked to disease on Brassica species since the 1970s, and yet its role has remained ambiguous. Re-examination of gene expression data revealed that all previously described genes and two newly identified genes within the sir gene cluster in the genome are down-regulated during the crucial early establishment stages of blackleg disease on Brassica napus. To test if this is a strategy employed by the fungus to avoid damage to and then detection by the host plant during the L. maculans asymptomatic biotrophic phase, sirodesmin was produced constitutively by overexpressing the sirZ gene encoding the transcription factor that coordinates the regulation of the other genes in the sir cluster. The sirZ over-expression strains had a major reduction in pathogenicity. Mutation of the over-expression construct restored pathogenicity. However, mutation of two genes, sirP and sirG, required for specific steps in the sirodesmin biosynthesis pathway, in the sirZ over-expression background resulted in strains that were unable to synthesize sirodesmin, yet were still non-pathogenic. Elucidating the basis for this pathogenicity defect or finding ways to overexpress sirZ during disease may provide new strategies for the control of blackleg disease.
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Affiliation(s)
- Andrew S. Urquhart
- School of BioSciences, The University of Melbourne, Melbourne, Victoria, Australia
- Applied BioSciences, Macquarie University, Macquarie Park, New South Wales, Australia
| | - Candace E. Elliott
- School of BioSciences, The University of Melbourne, Melbourne, Victoria, Australia
- Biosecurity Operations Division, Department of Agriculture, Water and the Environment, Post Entry Quarantine, Mickleham, Victoria, Australia
| | - Wei Zeng
- School of BioSciences, The University of Melbourne, Melbourne, Victoria, Australia
- Sino-Australia Plant Cell Wall Research Centre, State Key Laboratory of Subtropical Silviculture, Zhejiang A&F University, Hangzhou, China
| | - Alexander Idnurm
- School of BioSciences, The University of Melbourne, Melbourne, Victoria, Australia
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15
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Bhattarai K, Bhattarai K, Kabir ME, Bastola R, Baral B. Fungal natural products galaxy: Biochemistry and molecular genetics toward blockbuster drugs discovery. ADVANCES IN GENETICS 2021; 107:193-284. [PMID: 33641747 DOI: 10.1016/bs.adgen.2020.11.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/04/2022]
Abstract
Secondary metabolites synthesized by fungi have become a precious source of inspiration for the design of novel drugs. Indeed, fungi are prolific producers of fascinating, diverse, structurally complex, and low-molecular-mass natural products with high therapeutic leads, such as novel antimicrobial compounds, anticancer compounds, immunosuppressive agents, among others. Given that these microorganisms possess the extraordinary capacity to secrete diverse chemical scaffolds, they have been highly exploited by the giant pharma companies to generate small molecules. This has been made possible because the isolation of metabolites from fungal natural sources is feasible and surpasses the organic synthesis of compounds, which otherwise remains a significant bottleneck in the drug discovery process. Here in this comprehensive review, we have discussed recent studies on different fungi (pathogenic, non-pathogenic, commensal, and endophytic/symbiotic) from different habitats (terrestrial and marines), the specialized metabolites they biosynthesize, and the drugs derived from these specialized metabolites. Moreover, we have unveiled the logic behind the biosynthesis of vital chemical scaffolds, such as NRPS, PKS, PKS-NRPS hybrid, RiPPS, terpenoids, indole alkaloids, and their genetic mechanisms. Besides, we have provided a glimpse of the concept behind mycotoxins, virulence factor, and host immune response based on fungal infections.
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Affiliation(s)
- Keshab Bhattarai
- Pharmaceutical Institute, Department of Pharmaceutical Biology, University of Tübingen, Tübingen, Germany
| | - Keshab Bhattarai
- Central Department of Chemistry, Tribhuvan University, Kirtipur, Kathmandu, Nepal
| | - Md Ehsanul Kabir
- Animal Health Research Division, Bangladesh Livestock Research Institute, Savar, Dhaka, Bangladesh
| | - Rina Bastola
- Spinal Cord Injury Association-Nepal (SCIAN), Pokhara, Nepal
| | - Bikash Baral
- Department of Biochemistry, University of Turku, Turku, Finland.
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16
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Steenwyk JL, Mead ME, de Castro PA, Valero C, Damasio A, dos Santos RAC, Labella AL, Li Y, Knowles SL, Raja HA, Oberlies NH, Zhou X, Cornely OA, Fuchs F, Koehler P, Goldman GH, Rokas A. Genomic and phenotypic analysis of COVID-19-associated pulmonary aspergillosis isolates of Aspergillus fumigatus. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2020:2020.11.06.371971. [PMID: 33173866 PMCID: PMC7654854 DOI: 10.1101/2020.11.06.371971] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
The ongoing global pandemic caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the coronavirus disease 2019 (COVID-19) first described from Wuhan, China. A subset of COVID-19 patients has been reported to have acquired secondary infections by microbial pathogens, such as fungal opportunistic pathogens from the genus Aspergillus . To gain insight into COVID-19 associated pulmonary aspergillosis (CAPA), we analyzed the genomes and characterized the phenotypic profiles of four CAPA isolates of Aspergillus fumigatus obtained from patients treated in the area of North Rhine-Westphalia, Germany. By examining the mutational spectrum of single nucleotide polymorphisms, insertion-deletion polymorphisms, and copy number variants among 206 genes known to modulate A. fumigatus virulence, we found that CAPA isolate genomes do not exhibit major differences from the genome of the Af293 reference strain. By examining virulence in an invertebrate moth model, growth in the presence of osmotic, cell wall, and oxidative stressors, and the minimum inhibitory concentration of antifungal drugs, we found that CAPA isolates were generally, but not always, similar to A. fumigatus reference strains Af293 and CEA17. Notably, CAPA isolate D had more putative loss of function mutations in genes known to increase virulence when deleted (e.g., in the FLEA gene, which encodes a lectin recognized by macrophages). Moreover, CAPA isolate D was significantly more virulent than the other three CAPA isolates and the A. fumigatus reference strains tested. These findings expand our understanding of the genomic and phenotypic characteristics of isolates that cause CAPA.
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Affiliation(s)
- Jacob L. Steenwyk
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA
| | - Matthew E. Mead
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA
| | - Patrícia Alves de Castro
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Clara Valero
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - André Damasio
- Institute of Biology, University of Campinas (UNICAMP), Campinas-SP, Brazil
- Experimental Medicine Research Cluster (EMRC), University of Campinas (UNICAMP), Campinas-SP, Brazil
| | - Renato A. C. dos Santos
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Abigail L. Labella
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA
| | - Yuanning Li
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA
| | - Sonja L. Knowles
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, North Carolina 27402
| | - Huzefa A. Raja
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, North Carolina 27402
| | - Nicholas H. Oberlies
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, North Carolina 27402
| | - Xiaofan Zhou
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangdong Province Key Laboratory of Microbial Signals and Disease Control, Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou, China
| | - Oliver A. Cornely
- University of Cologne, Medical Faculty and University Hospital Cologne, Department I of Internal Medicine, Excellence Center for Medical Mycology (ECMM), Cologne, Germany
- University of Cologne, Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Cologne, Germany
- ZKS Köln, Clinical Trials Centre Cologne, Cologne, Germany
- German Center for Infection Research (DZIF), Partner Site Bonn Cologne, Medical Faculty and University Hospital Cologne, University of Cologne, Cologne, Germany
| | - Frieder Fuchs
- Faculty of Medicine, Institute for Medical Microbiology, Immunology and Hygiene, University of Cologne, Cologne, Germany
| | - Philipp Koehler
- University of Cologne, Medical Faculty and University Hospital Cologne, Department I of Internal Medicine, Excellence Center for Medical Mycology (ECMM), Cologne, Germany
- University of Cologne, Cologne Excellence Cluster on Cellular Stress Responses in Aging-Associated Diseases (CECAD), Cologne, Germany
| | - Gustavo H. Goldman
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Antonis Rokas
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA
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17
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Zheng T, Wang M, Zhan J, Sun W, Yang Q, Lin Z, Bu T, Tang Z, Li C, Yan J, Shan Z, Chen H. Ferrous iron-induced increases in capitate glandular trichome density and upregulation of CbHO-1 contributes to increases in blinin content in Conyza blinii. PLANTA 2020; 252:81. [PMID: 33037484 DOI: 10.1007/s00425-020-03492-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Accepted: 10/04/2020] [Indexed: 06/11/2023]
Abstract
Ferrous iron can promote the development of glandular trichomes and increase the content of blinin, which depends on CbHO-1 expression. Conyza blinii (C. blinii) is a unique Chinese herbal medicine that grows in Sichuan Province, China. Because the habitat of C. blinii is an iron ore mining area with abundant iron content, this species can be used as one of the best materials to study the mechanism of plant tolerance to iron. In this study, C. blinii was treated with ferrous-EDTA solutions at different concentrations, and it was found that the tolerance value of C. blinii to iron was 200 μM. Under this concentration, the plant height, root length, biomass, and iron content of C. blinii increased to the maximum values, and the effect was dependent on the upregulated expression of CbHO-1. At the same time, under ferrous iron, the photosynthetic capacity and capitate glandular trichome density of C. blinii also significantly increased, providing precursors and sites for the synthesis of blinin, thus significantly increasing the content of blinin. These processes were also dependent on the high expression of CbHO-1. Correlation analysis showed that there were strong positive correlations between iron content, capitate glandular trichome density, CbHO-1 gene expression, and blinin content. This study explored the effects of ferrous iron on the physiology and biochemistry of C. blinii, greatly improving our understanding of the mechanism of iron tolerance in C. blinii.
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Affiliation(s)
- Tianrun Zheng
- College of Life Science, Sichuan Agricultural University, Ya'an, China
| | - Maojia Wang
- College of Life Science, Sichuan Agricultural University, Ya'an, China
| | - Junyi Zhan
- College of Life Science, Sichuan Agricultural University, Ya'an, China
| | - Wenjun Sun
- College of Life Science, Sichuan Agricultural University, Ya'an, China
| | - Qin Yang
- College of Life Science, Sichuan Agricultural University, Ya'an, China
| | - Zhiyi Lin
- College of Life Science, Sichuan Agricultural University, Ya'an, China
| | - Tongliang Bu
- College of Life Science, Sichuan Agricultural University, Ya'an, China
| | - Zizhong Tang
- College of Life Science, Sichuan Agricultural University, Ya'an, China
| | - Chenglei Li
- College of Life Science, Sichuan Agricultural University, Ya'an, China
| | - Jun Yan
- Key Laboratory of Coarse Cereal Processing, Ministry of Agriculture Rural Affairs, School of Food and Bioengineering, Chengdu University, Chengdu, China
| | - Zhi Shan
- College of Life Science, Sichuan Agricultural University, Ya'an, China
| | - Hui Chen
- College of Life Science, Sichuan Agricultural University, Ya'an, China.
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18
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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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19
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Steenwyk JL, Mead ME, Knowles SL, Raja HA, Roberts CD, Bader O, Houbraken J, Goldman GH, Oberlies NH, Rokas A. Variation Among Biosynthetic Gene Clusters, Secondary Metabolite Profiles, and Cards of Virulence Across Aspergillus Species. Genetics 2020; 216:481-497. [PMID: 32817009 PMCID: PMC7536862 DOI: 10.1534/genetics.120.303549] [Citation(s) in RCA: 41] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2020] [Accepted: 08/01/2020] [Indexed: 02/07/2023] Open
Abstract
Aspergillus fumigatus is a major human pathogen. In contrast, Aspergillus fischeri and the recently described Aspergillus oerlinghausenensis, the two species most closely related to A. fumigatus, are not known to be pathogenic. Some of the genetic determinants of virulence (or "cards of virulence") that A. fumigatus possesses are secondary metabolites that impair the host immune system, protect from host immune cell attacks, or acquire key nutrients. To examine whether secondary metabolism-associated cards of virulence vary between these species, we conducted extensive genomic and secondary metabolite profiling analyses of multiple A. fumigatus, one A. oerlinghausenensis, and multiple A. fischeri strains. We identified two cards of virulence (gliotoxin and fumitremorgin) shared by all three species and three cards of virulence (trypacidin, pseurotin, and fumagillin) that are variable. For example, we found that all species and strains examined biosynthesized gliotoxin, which is known to contribute to virulence, consistent with the conservation of the gliotoxin biosynthetic gene cluster (BGC) across genomes. For other secondary metabolites, such as fumitremorgin, a modulator of host biology, we found that all species produced the metabolite but that there was strain heterogeneity in its production within species. Finally, species differed in their biosynthesis of fumagillin and pseurotin, both contributors to host tissue damage during invasive aspergillosis. A. fumigatus biosynthesized fumagillin and pseurotin, while A. oerlinghausenensis biosynthesized fumagillin and A. fischeri biosynthesized neither. These biochemical differences were reflected in sequence divergence of the intertwined fumagillin/pseurotin BGCs across genomes. These results delineate the similarities and differences in secondary metabolism-associated cards of virulence between a major fungal pathogen and its nonpathogenic closest relatives, shedding light onto the genetic and phenotypic changes associated with the evolution of fungal pathogenicity.
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Affiliation(s)
- Jacob L Steenwyk
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee 37235
| | - Matthew E Mead
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee 37235
| | - Sonja L Knowles
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, North Carolina 27402
| | - Huzefa A Raja
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, North Carolina 27402
| | - Christopher D Roberts
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, North Carolina 27402
| | - Oliver Bader
- Institute for Medical Microbiology, University Medical Center Göttingen, 37075, Germany
| | - Jos Houbraken
- Westerdijk Fungal Biodiversity Institute, 3584 CT Utrecht, The Netherlands
| | - Gustavo H Goldman
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, 14040-900 Brazil
| | - Nicholas H Oberlies
- Department of Chemistry and Biochemistry, University of North Carolina at Greensboro, North Carolina 27402
| | - Antonis Rokas
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee 37235
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20
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Huang X, Zhang W, Tang S, Wei S, Lu X. Collaborative Biosynthesis of a Class of Bioactive Azaphilones by Two Separate Gene Clusters Containing Four PKS/NRPSs with Transcriptional Crosstalk in Fungi. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201915514] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Xuenian Huang
- Shandong Provincial Key Laboratory of Synthetic BiologyKey Laboratory of BiofuelsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of Sciences No. 189 Songling Road Qingdao 266101 China
| | - Wei Zhang
- Shandong Provincial Key Laboratory of Synthetic BiologyKey Laboratory of BiofuelsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of Sciences No. 189 Songling Road Qingdao 266101 China
| | - Shen Tang
- Shandong Provincial Key Laboratory of Synthetic BiologyKey Laboratory of BiofuelsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of Sciences No. 189 Songling Road Qingdao 266101 China
- College of Bioscience and BioengineeringJiangxi Agricultural University No. 1101 Zhimin Road Nanchang 330045 China
| | - Suhui Wei
- Shandong Provincial Key Laboratory of Synthetic BiologyKey Laboratory of BiofuelsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of Sciences No. 189 Songling Road Qingdao 266101 China
| | - Xuefeng Lu
- Shandong Provincial Key Laboratory of Synthetic BiologyKey Laboratory of BiofuelsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of Sciences No. 189 Songling Road Qingdao 266101 China
- Marine Biology and Biotechnology LaboratoryQingdao National Laboratory for Marine Science and Technology No. 1 Wenhai Road, Aoshanwei Qingdao 266101 China
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21
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Huang X, Zhang W, Tang S, Wei S, Lu X. Collaborative Biosynthesis of a Class of Bioactive Azaphilones by Two Separate Gene Clusters Containing Four PKS/NRPSs with Transcriptional Crosstalk in Fungi. Angew Chem Int Ed Engl 2020; 59:4349-4353. [DOI: 10.1002/anie.201915514] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2019] [Indexed: 01/25/2023]
Affiliation(s)
- Xuenian Huang
- Shandong Provincial Key Laboratory of Synthetic BiologyKey Laboratory of BiofuelsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of Sciences No. 189 Songling Road Qingdao 266101 China
| | - Wei Zhang
- Shandong Provincial Key Laboratory of Synthetic BiologyKey Laboratory of BiofuelsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of Sciences No. 189 Songling Road Qingdao 266101 China
| | - Shen Tang
- Shandong Provincial Key Laboratory of Synthetic BiologyKey Laboratory of BiofuelsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of Sciences No. 189 Songling Road Qingdao 266101 China
- College of Bioscience and BioengineeringJiangxi Agricultural University No. 1101 Zhimin Road Nanchang 330045 China
| | - Suhui Wei
- Shandong Provincial Key Laboratory of Synthetic BiologyKey Laboratory of BiofuelsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of Sciences No. 189 Songling Road Qingdao 266101 China
| | - Xuefeng Lu
- Shandong Provincial Key Laboratory of Synthetic BiologyKey Laboratory of BiofuelsQingdao Institute of Bioenergy and Bioprocess TechnologyChinese Academy of Sciences No. 189 Songling Road Qingdao 266101 China
- Marine Biology and Biotechnology LaboratoryQingdao National Laboratory for Marine Science and Technology No. 1 Wenhai Road, Aoshanwei Qingdao 266101 China
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Abstract
Aspergillus fumigatus is a saprotrophic fungus; its primary habitat is the soil. In its ecological niche, the fungus has learned how to adapt and proliferate in hostile environments. This capacity has helped the fungus to resist and survive against human host defenses and, further, to be responsible for one of the most devastating lung infections in terms of morbidity and mortality. In this review, we will provide (i) a description of the biological cycle of A. fumigatus; (ii) a historical perspective of the spectrum of aspergillus disease and the current epidemiological status of these infections; (iii) an analysis of the modes of immune response against Aspergillus in immunocompetent and immunocompromised patients; (iv) an understanding of the pathways responsible for fungal virulence and their host molecular targets, with a specific focus on the cell wall; (v) the current status of the diagnosis of different clinical syndromes; and (vi) an overview of the available antifungal armamentarium and the therapeutic strategies in the clinical context. In addition, the emergence of new concepts, such as nutritional immunity and the integration and rewiring of multiple fungal metabolic activities occurring during lung invasion, has helped us to redefine the opportunistic pathogenesis of A. fumigatus.
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Affiliation(s)
- Jean-Paul Latgé
- School of Medicine, University of Crete, Heraklion, Crete, Greece
| | - Georgios Chamilos
- School of Medicine, University of Crete, Heraklion, Crete, Greece
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology, Heraklion, Crete, Greece
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23
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Greco C, Pfannenstiel BT, Liu JC, Keller NP. Depsipeptide Aspergillicins Revealed by Chromatin Reader Protein Deletion. ACS Chem Biol 2019; 14:1121-1128. [PMID: 31117395 DOI: 10.1021/acschembio.9b00161] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
Expression of biosynthetic gene clusters (BGCs) in filamentous fungi is highly regulated by epigenetic remodeling of chromatin structure. Two classes of histone modifying proteins, writers (which place modifications on histone tails) and erasers (which remove the modifications), have been used extensively to activate cryptic BGCs in fungi. Here, for the first time, we present activation of a cryptic BGC by a third category of histone modifying proteins, reader proteins that recognize histone tail modifications and commonly mediate writer and eraser activity. Loss of the reader SntB (Δ sntB) resulted in the synthesis of two cryptic cyclic hexa-depsipeptides, aspergillicin A and aspergillicin F, in the fungus Aspergillus flavus. Liquid chromatography, high resolution mass spectrometry, and NMR analysis coupled with bioinformatic analysis and gene deletion experiments revealed that a six adenylation (A) domain nonribosomal peptide synthetase (NRPS, called AgiA) and O-methyltransferase (AgiB) were required for metabolite formation. A proposed biosynthetic scheme illustrates the requirement for unusual NRPS domains, such as a starting condensation domain and a thiolesterase domain proposed to cyclize the depsipeptides. This latter activity has only been found in bacterial but not fungal NRPS. The agi BGC-unique to A. flavus and some closely related species (e.g., A. oryzae, A. arachidicola)-is located next to a conserved Aspergillus siderophore BGC syntenic to other fungi.
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Affiliation(s)
- Claudio Greco
- Department of Medical Microbiology and Immunology, University of Wisconsin—Madison, Madison, Wisconsin, United States
| | | | - James C. Liu
- Department of Medical Microbiology and Immunology, University of Wisconsin—Madison, Madison, Wisconsin, United States
| | - Nancy P. Keller
- Department of Medical Microbiology and Immunology, University of Wisconsin—Madison, Madison, Wisconsin, United States
- Department of Bacteriology, University of Wisconsin—Madison, Madison, Wisconsin, United States
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Romsdahl J, Wang CCC. Recent advances in the genome mining of Aspergillus secondary metabolites (covering 2012-2018). MEDCHEMCOMM 2019; 10:840-866. [PMID: 31303983 PMCID: PMC6590338 DOI: 10.1039/c9md00054b] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 04/11/2019] [Indexed: 02/01/2023]
Abstract
Secondary metabolites (SMs) produced by filamentous fungi possess diverse bioactivities that make them excellent drug candidates. Whole genome sequencing has revealed that fungi have the capacity to produce a far greater number of SMs than have been isolated, since many of the genes involved in SM biosynthesis are either silent or expressed at very low levels in standard laboratory conditions. There has been significant effort to activate SM biosynthetic genes and link them to their downstream products, as the SMs produced by these "cryptic" pathways offer a promising source for new drug discovery. Further, an understanding of the genes involved in SM biosynthesis facilitates product yield optimization of first-generation molecules and genetic engineering of second-generation analogs. This review covers advances made in genome mining SMs produced by Aspergillus nidulans, Aspergillus fumigatus, Aspergillus niger, and Aspergillus terreus in the past six years (2012-2018). Genetic identification and molecular characterization of SM biosynthetic gene clusters, along with proposed biosynthetic pathways, will be discussed in depth.
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Affiliation(s)
- Jillian Romsdahl
- Department of Pharmacology and Pharmaceutical Sciences , School of Pharmacy , University of Southern California , 1985 Zonal Avenue , Los Angeles , CA 90089 , USA . ; Tel: (323) 442 1670
| | - Clay C C Wang
- Department of Pharmacology and Pharmaceutical Sciences , School of Pharmacy , University of Southern California , 1985 Zonal Avenue , Los Angeles , CA 90089 , USA . ; Tel: (323) 442 1670
- Department of Chemistry , Dornsife College of Letters, Arts, and Sciences , University of Southern California , 3551 Trousdale Pkwy , Los Angeles , CA 90089 , USA
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25
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Copper Utilization, Regulation, and Acquisition by Aspergillus fumigatus. Int J Mol Sci 2019; 20:ijms20081980. [PMID: 31018527 PMCID: PMC6514546 DOI: 10.3390/ijms20081980] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2019] [Revised: 04/16/2019] [Accepted: 04/17/2019] [Indexed: 01/01/2023] Open
Abstract
Copper is an essential micronutrient for the opportunistic human pathogen, Aspergillus fumigatus. Maintaining copper homeostasis is critical for survival and pathogenesis. Copper-responsive transcription factors, AceA and MacA, coordinate a complex network responsible for responding to copper in the environment and determining which response is necessary to maintain homeostasis. For example, A. fumigatus uses copper exporters to mitigate the toxic effects of copper while simultaneously encoding copper importers and small molecules to ensure proper supply of the metal for copper-dependent processes such a nitrogen acquisition and respiration. Small molecules called isocyanides recently found to be produced by A. fumigatus may bind copper and partake in copper homeostasis similarly to isocyanide copper chelators in bacteria. Considering that the host uses copper as a microbial toxin and copper availability fluctuates in various environmental niches, understanding how A. fumigatus maintains copper homeostasis will give insights into mechanisms that facilitate the development of invasive aspergillosis and its survival in nature.
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26
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Raffa N, Keller NP. A call to arms: Mustering secondary metabolites for success and survival of an opportunistic pathogen. PLoS Pathog 2019; 15:e1007606. [PMID: 30947302 PMCID: PMC6448812 DOI: 10.1371/journal.ppat.1007606] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/04/2022] Open
Affiliation(s)
- Nicholas Raffa
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
| | - Nancy P. Keller
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin, United States of America
- * E-mail:
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27
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Abstract
One of the exciting movements in microbial sciences has been a refocusing and revitalization of efforts to mine the fungal secondary metabolome. The magnitude of biosynthetic gene clusters (BGCs) in a single filamentous fungal genome combined with the historic number of sequenced genomes suggests that the secondary metabolite wealth of filamentous fungi is largely untapped. Mining algorithms and scalable expression platforms have greatly expanded access to the chemical repertoire of fungal-derived secondary metabolites. In this Review, I discuss new insights into the transcriptional and epigenetic regulation of BGCs and the ecological roles of fungal secondary metabolites in warfare, defence and development. I also explore avenues for the identification of new fungal metabolites and the challenges in harvesting fungal-derived secondary metabolites.
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28
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Pidroni A, Faber B, Brosch G, Bauer I, Graessle S. A Class 1 Histone Deacetylase as Major Regulator of Secondary Metabolite Production in Aspergillus nidulans. Front Microbiol 2018; 9:2212. [PMID: 30283426 PMCID: PMC6156440 DOI: 10.3389/fmicb.2018.02212] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2018] [Accepted: 08/30/2018] [Indexed: 12/23/2022] Open
Abstract
An outstanding feature of filamentous fungi is their ability to produce a wide variety of small bioactive molecules that contribute to their survival, fitness, and pathogenicity. The vast collection of these so-called secondary metabolites (SMs) includes molecules that play a role in virulence, protect fungi from environmental damage, act as toxins or antibiotics that harm host tissues, or hinder microbial competitors for food sources. Many of these compounds are used in medical treatment; however, biosynthetic genes for the production of these natural products are arranged in compact clusters that are commonly silent under growth conditions routinely used in laboratories. Consequently, a wide arsenal of yet unknown fungal metabolites is waiting to be discovered. Here, we describe the effects of deletion of hosA, one of four classical histone deacetylase (HDAC) genes in Aspergillus nidulans; we show that HosA acts as a major regulator of SMs in Aspergillus with converse regulatory effects depending on the metabolite gene cluster examined. Co-inhibition of all classical enzymes by the pan HDAC inhibitor trichostatin A and the analysis of HDAC double mutants indicate that HosA is able to override known regulatory effects of other HDACs such as the class 2 type enzyme HdaA. Chromatin immunoprecipitation analysis revealed a direct correlation between hosA deletion, the acetylation status of H4 and the regulation of SM cluster genes, whereas H3 hyper-acetylation could not be detected in all the upregulated SM clusters examined. Our data suggest that HosA has inductive effects on SM production in addition to its classical role as a repressor via deacetylation of histones. Moreover, a genome wide transcriptome analysis revealed that in addition to SMs, expression of several other important protein categories such as enzymes of the carbohydrate metabolism or proteins involved in disease, virulence, and defense are significantly affected by the deletion of HosA.
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Affiliation(s)
- Angelo Pidroni
- Division of Molecular Biology, Medical University of Innsbruck, Innsbruck, Austria
| | - Birgit Faber
- Division of Molecular Biology, Medical University of Innsbruck, Innsbruck, Austria
| | - Gerald Brosch
- Division of Molecular Biology, Medical University of Innsbruck, Innsbruck, Austria
| | - Ingo Bauer
- Division of Molecular Biology, Medical University of Innsbruck, Innsbruck, Austria
| | - Stefan Graessle
- Division of Molecular Biology, Medical University of Innsbruck, Innsbruck, Austria
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29
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Abstract
Microbial secondary metabolites, including isocyanide moieties, have been extensively mined for their repertoire of bioactive properties. Although the first naturally occurring isocyanide (xanthocillin) was isolated from the fungus Penicillium notatum over half a century ago, the biosynthetic origins of fungal isocyanides remain unknown. Here we report the identification of a family of isocyanide synthases (ICSs) from the opportunistic human pathogen Aspergillus fumigatus Comparative metabolomics of overexpression or knockout mutants of ICS candidate genes led to the discovery of a fungal biosynthetic gene cluster (BGC) that produces xanthocillin (xan). Detailed analysis of xanthocillin biosynthesis in A. fumigatus revealed several previously undescribed compounds produced by the xan BGC, including two novel members of the melanocin family of compounds. We found both the xan BGC and a second ICS-containing cluster, named the copper-responsive metabolite (crm) BGC, to be transcriptionally responsive to external copper levels and further demonstrated that production of metabolites from the xan BGC is increased during copper starvation. The crm BGC includes a novel type of fungus-specific ICS-nonribosomal peptide synthase (NRPS) hybrid enzyme, CrmA. This family of ICS-NRPS hybrid enzymes is highly enriched in fungal pathogens of humans, insects, and plants. Phylogenetic assessment of all ICSs spanning the tree of life shows not only high prevalence throughout the fungal kingdom but also distribution in species not previously known to harbor BGCs, indicating an untapped resource of fungal secondary metabolism.IMPORTANCE Fungal ICSs are an untapped resource in fungal natural product research. Their isocyanide products have been implicated in plant and insect pathogenesis due to their ability to coordinate transition metals and disable host metalloenzymes. The discovery of a novel isocyanide-producing family of hybrid ICS-NRPS enzymes enriched in medically and agriculturally important fungal pathogens may reveal mechanisms underlying pathogenicity and afford opportunities to discover additional families of isocyanides. Furthermore, the identification of noncanonical ICS BGCs will enable refinement of BGC prediction algorithms to expand on the secondary metabolic potential of fungal and bacterial species. The identification of genes related to ICS BGCs in fungal species not previously known for secondary metabolite-producing capabilities (e.g., Saccharomyces spp.) contributes to our understanding of the evolution of BGC in fungi.
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Kurucz V, Krüger T, Antal K, Dietl AM, Haas H, Pócsi I, Kniemeyer O, Emri T. Additional oxidative stress reroutes the global response of Aspergillus fumigatus to iron depletion. BMC Genomics 2018; 19:357. [PMID: 29747589 PMCID: PMC5946477 DOI: 10.1186/s12864-018-4730-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2017] [Accepted: 04/26/2018] [Indexed: 01/10/2023] Open
Abstract
BACKGROUND Aspergillus fumigatus has to cope with a combination of several stress types while colonizing the human body. A functional interplay between these different stress responses can increase the chances of survival for this opportunistic human pathogen during the invasion of its host. In this study, we shed light on how the H2O2-induced oxidative stress response depends on the iron available to this filamentous fungus, using transcriptomic analysis, proteomic profiles, and growth assays. RESULTS The applied H2O2 treatment, which induced only a negligible stress response in iron-replete cultures, deleteriously affected the fungus under iron deprivation. The majority of stress-induced changes in gene and protein expression was not predictable from data coming from individual stress exposure and was only characteristic for the combination of oxidative stress plus iron deprivation. Our experimental data suggest that the physiological effects of combined stresses and the survival of the fungus highly depend on fragile balances between economization of iron and production of essential iron-containing proteins. One observed strategy was the overproduction of iron-independent antioxidant proteins to combat oxidative stress during iron deprivation, e.g. the upregulation of superoxide dismutase Sod1, the thioredoxin reductase Trr1, and the thioredoxin orthologue Afu5g11320. On the other hand, oxidative stress induction overruled iron deprivation-mediated repression of several genes. In agreement with the gene expression data, growth studies underlined that in A. fumigatus iron deprivation aggravates oxidative stress susceptibility. CONCLUSIONS Our data demonstrate that studying stress responses under separate single stress conditions is not sufficient to understand how A. fumigatus adapts in a complex and hostile habitat like the human body. The combinatorial stress of iron depletion and hydrogen peroxide caused clear non-additive effects upon the stress response of A. fumigatus. Our data further supported the view that the ability of A. fumigatus to cause diseases in humans strongly depends on its fitness attributes and less on specific virulence factors. In summary, A. fumigatus is able to mount and coordinate complex and efficient responses to combined stresses like iron deprivation plus H2O2-induced oxidative stress, which are exploited by immune cells to kill fungal pathogens.
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Affiliation(s)
- Vivien Kurucz
- Department of Biotechnology and Microbiology, Faculty of Sciences and Technology, University of Debrecen, Egyetem tér 1, Debrecen, H-4032 Hungary
| | - Thomas Krüger
- Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knöll Institute (HKI), 07745 Jena, Germany
| | - Károly Antal
- Department of Zoology, Faculty of Sciences, Eszterházy Károly University, Eszterházy tér 1, Eger, H-3300 Hungary
| | - Anna-Maria Dietl
- Division of Molecular Biology, Biocenter, Medical University of Innsbruck, A6020 Innsbruck, Austria
| | - Hubertus Haas
- Division of Molecular Biology, Biocenter, Medical University of Innsbruck, A6020 Innsbruck, Austria
| | - István Pócsi
- Department of Biotechnology and Microbiology, Faculty of Sciences and Technology, University of Debrecen, Egyetem tér 1, Debrecen, H-4032 Hungary
| | - Olaf Kniemeyer
- Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knöll Institute (HKI), 07745 Jena, Germany
| | - Tamás Emri
- Department of Biotechnology and Microbiology, Faculty of Sciences and Technology, University of Debrecen, Egyetem tér 1, Debrecen, H-4032 Hungary
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Lind AL, Lim FY, Soukup AA, Keller NP, Rokas A. An LaeA- and BrlA-Dependent Cellular Network Governs Tissue-Specific Secondary Metabolism in the Human Pathogen Aspergillus fumigatus. mSphere 2018; 3:e00050-18. [PMID: 29564395 PMCID: PMC5853485 DOI: 10.1128/msphere.00050-18] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 02/21/2018] [Indexed: 12/17/2022] Open
Abstract
Biosynthesis of many ecologically important secondary metabolites (SMs) in filamentous fungi is controlled by several global transcriptional regulators, like the chromatin modifier LaeA, and tied to both development and vegetative growth. In Aspergillus molds, asexual development is regulated by the BrlA > AbaA > WetA transcriptional cascade. To elucidate BrlA pathway involvement in SM regulation, we examined the transcriptional and metabolic profiles of ΔbrlA, ΔabaA, and ΔwetA mutant and wild-type strains of the human pathogen Aspergillus fumigatus. We find that BrlA, in addition to regulating production of developmental SMs, regulates vegetative SMs and the SrbA-regulated hypoxia stress response in a concordant fashion to LaeA. We further show that the transcriptional and metabolic equivalence of the ΔbrlA and ΔlaeA mutations is mediated by an LaeA requirement preventing heterochromatic marks in the brlA promoter. These results provide a framework for the cellular network regulating not only fungal SMs but diverse cellular processes linked to virulence of this pathogen. IMPORTANCE Filamentous fungi produce a spectacular variety of small molecules, commonly known as secondary or specialized metabolites (SMs), which are critical to their ecologies and lifestyles (e.g., penicillin, cyclosporine, and aflatoxin). Elucidation of the regulatory network that governs SM production is a major question of both fundamental and applied research relevance. To shed light on the relationship between regulation of development and regulation of secondary metabolism in filamentous fungi, we performed global transcriptomic and metabolomic analyses on mutant and wild-type strains of the human pathogen Aspergillus fumigatus under conditions previously shown to induce the production of both vegetative growth-specific and asexual development-specific SMs. We find that the gene brlA, previously known as a master regulator of asexual development, is also a master regulator of secondary metabolism and other cellular processes. We further show that brlA regulation of SM is mediated by laeA, one of the master regulators of SM, providing a framework for the cellular network regulating not only fungal SMs but diverse cellular processes linked to virulence of this pathogen.
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Affiliation(s)
- Abigail L. Lind
- Department of Biomedical Informatics, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
| | - Fang Yun Lim
- Department of Medical Microbiology & Immunology, University of Wisconsin—Madison, Madison, Wisconsin, USA
| | - Alexandra A. Soukup
- Department of Genetics, University of Wisconsin—Madison, Madison, Wisconsin, USA
| | - Nancy P. Keller
- Department of Medical Microbiology & Immunology, University of Wisconsin—Madison, Madison, Wisconsin, USA
| | - Antonis Rokas
- Department of Biomedical Informatics, Vanderbilt University School of Medicine, Nashville, Tennessee, USA
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee, USA
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Choera T, Zelante T, Romani L, Keller NP. A Multifaceted Role of Tryptophan Metabolism and Indoleamine 2,3-Dioxygenase Activity in Aspergillus fumigatus-Host Interactions. Front Immunol 2018; 8:1996. [PMID: 29403477 PMCID: PMC5786828 DOI: 10.3389/fimmu.2017.01996] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2017] [Accepted: 12/22/2017] [Indexed: 12/19/2022] Open
Abstract
Aspergillus fumigatus is the most prevalent filamentous fungal pathogen of humans, causing either severe allergic bronchopulmonary aspergillosis or often fatal invasive pulmonary aspergillosis (IPA) in individuals with hyper- or hypo-immune deficiencies, respectively. Disease is primarily initiated upon the inhalation of the ubiquitous airborne conidia—the initial inoculum produced by A. fumigatus—which are complete developmental units with an ability to exploit diverse environments, ranging from agricultural composts to animal lungs. Upon infection, conidia initially rely on their own metabolic processes for survival in the host’s lungs, a nutritionally limiting environment. One such nutritional limitation is the availability of aromatic amino acids (AAAs) as animals lack the enzymes to synthesize tryptophan (Trp) and phenylalanine and only produce tyrosine from dietary phenylalanine. However, A. fumigatus produces all three AAAs through the shikimate–chorismate pathway, where they play a critical role in fungal growth and development and in yielding many downstream metabolites. The downstream metabolites of Trp in A. fumigatus include the immunomodulatory kynurenine derived from indoleamine 2,3-dioxygenase (IDO) and toxins such as fumiquinazolines, gliotoxin, and fumitremorgins. Host IDO activity and/or host/microbe-derived kynurenines are increasingly correlated with many Aspergillus diseases including IPA and infections of chronic granulomatous disease patients. In this review, we will describe the potential metabolic cross talk between the host and the pathogen, specifically focusing on Trp metabolism, the implications for therapeutics, and the recent studies on the coevolution of host and microbe IDO activation in regulating inflammation, while controlling infection.
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Affiliation(s)
- Tsokyi Choera
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI, United States
| | - Teresa Zelante
- Department of Experimental Medicine, University of Perugia, Perugia, Italy
| | - Luigina Romani
- Department of Experimental Medicine, University of Perugia, Perugia, Italy
| | - Nancy P Keller
- Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, WI, United States.,Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, United States
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Guruceaga X, Ezpeleta G, Mayayo E, Sueiro-Olivares M, Abad-Diaz-De-Cerio A, Aguirre Urízar JM, Liu HG, Wiemann P, Bok JW, Filler SG, Keller NP, Hernando FL, Ramirez-Garcia A, Rementeria A. A possible role for fumagillin in cellular damage during host infection by Aspergillus fumigatus. Virulence 2018; 9:1548-1561. [PMID: 30251593 PMCID: PMC6177242 DOI: 10.1080/21505594.2018.1526528] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 09/10/2018] [Indexed: 01/31/2023] Open
Abstract
Virulence mechanisms of the pathogenic fungus Aspergillus fumigatus are multifactorial and depend on the immune state of the host, but little is known about the fungal mechanism that develops during the process of lung invasion. In this study, microarray technology was combined with a histopathology evaluation of infected lungs so that the invasion strategy followed by the fungus could be described. To achieve this, an intranasal mice infection was performed to extract daily fungal samples from the infected lungs over four days post-infection. The pathological study revealed a heavy fungal progression throughout the lung, reaching the blood vessels on the third day after exposure and causing tissue necrosis. One percent of the fungal genome followed a differential expression pattern during this process. Strikingly, most of the genes of the intertwined fumagillin/pseurotin biosynthetic gene cluster were upregulated as were genes encoding lytic enzymes such as lipases, proteases (DppIV, DppV, Asp f 1 or Asp f 5) and chitinase (chiB1) as well as three genes related with pyomelanin biosynthesis process. Furthermore, we demonstrate that fumagillin is produced in an in vitro pneumocyte cell line infection model and that loss of fumagillin synthesis reduces epithelial cell damage. These results suggest that fumagillin contributes to tissue damage during invasive aspergillosis. Therefore, it is probable that A. fumigatus progresses through the lungs via the production of the mycotoxin fumagillin combined with the secretion of lytic enzymes that allow fungal growth, angioinvasion and the disruption of the lung parenchymal structure.
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Affiliation(s)
- Xabier Guruceaga
- Fungal and Bacterial Biomics Research Group, Department of Immunology, Microbiology and Parasitology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Leioa, Spain
| | - Guillermo Ezpeleta
- Preventive Medicine and Hospital Hygiene Service, Complejo Hospitalario de Navarra, Pamplona, Spain
- Department of Preventive Medicine and Public Health, Faculty of Medicine and Nursing, University of the Basque Country (UPV/EHU), Leioa, Spain
| | - Emilio Mayayo
- Pathology Unit, Medicine and Health Science Faculty, University of Rovira i Virgili, Reus, Tarragona, Spain
| | - Monica Sueiro-Olivares
- Fungal and Bacterial Biomics Research Group, Department of Immunology, Microbiology and Parasitology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Leioa, Spain
| | - Ana Abad-Diaz-De-Cerio
- Fungal and Bacterial Biomics Research Group, Department of Immunology, Microbiology and Parasitology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Leioa, Spain
| | - José Manuel Aguirre Urízar
- Department of Stomatology II, Faculty of Medicine and Nursing, University of the Basque Country (UPV/EHU), Leioa, Spain
| | - Hong G. Liu
- Division of Infectious Diseases, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, Torrance, CA, USA
- Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Philipp Wiemann
- Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, WI, USA
| | - Jin Woo Bok
- Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, WI, USA
| | - Scott G. Filler
- Division of Infectious Diseases, Los Angeles Biomedical Research Institute at Harbor-UCLA Medical Center, Torrance, CA, USA
- Department of Medicine, David Geffen School of Medicine at UCLA, Los Angeles, CA, USA
| | - Nancy P. Keller
- Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, WI, USA
- Department of Bacteriology, University of Wisconsin, Madison, WI, USA
| | - Fernando L. Hernando
- Fungal and Bacterial Biomics Research Group, Department of Immunology, Microbiology and Parasitology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Leioa, Spain
| | - Andoni Ramirez-Garcia
- Fungal and Bacterial Biomics Research Group, Department of Immunology, Microbiology and Parasitology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Leioa, Spain
| | - Aitor Rementeria
- Fungal and Bacterial Biomics Research Group, Department of Immunology, Microbiology and Parasitology, Faculty of Science and Technology, University of the Basque Country (UPV/EHU), Leioa, Spain
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Bignell E, Cairns TC, Throckmorton K, Nierman WC, Keller NP. Secondary metabolite arsenal of an opportunistic pathogenic fungus. Philos Trans R Soc Lond B Biol Sci 2017; 371:rstb.2016.0023. [PMID: 28080993 DOI: 10.1098/rstb.2016.0023] [Citation(s) in RCA: 59] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/26/2016] [Indexed: 12/31/2022] Open
Abstract
Aspergillus fumigatus is a versatile fungus able to successfully exploit diverse environments from mammalian lungs to agricultural waste products. Among its many fitness attributes are dozens of genetic loci containing biosynthetic gene clusters (BGCs) producing bioactive small molecules (often referred to as secondary metabolites or natural products) that provide growth advantages to the fungus dependent on environment. Here we summarize the current knowledge of these BGCs-18 of which can be named to product-their expression profiles in vivo, and which BGCs may enhance virulence of this opportunistic human pathogen. Furthermore, we find extensive evidence for the presence of many of these BGCs, or similar BGCs, in distantly related genera including the emerging pathogen Pseudogymnoascus destructans, the causative agent of white-nose syndrome in bats, and suggest such BGCs may be predictive of pathogenic potential in other fungi.This article is part of the themed issue 'Tackling emerging fungal threats to animal health, food security and ecosystem resilience'.
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Affiliation(s)
- Elaine Bignell
- Manchester Fungal Infection Group, Institute of Inflammation and Repair, 2.24 Core Technology Facility, Grafton Street, Manchester, M13 9NT, UK
| | - Timothy C Cairns
- Department of Applied and Molecular Microbiology, Institute of Biotechnology, Berlin University of Technology, Gustav-Meyer-Allee 25, 13355 Berlin, Germany
| | - Kurt Throckmorton
- Department of Bacteriology, University of Wisconsin, Madison, WI 53706, USA
| | | | - Nancy P Keller
- Department of Bacteriology, University of Wisconsin, Madison, WI 53706, USA, .,Department of Medical Microbiology, University of Wisconsin, Madison, WI 53706, USA
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Han X, Chakrabortti A, Zhu J, Liang ZX, Li J. Sequencing and functional annotation of the whole genome of the filamentous fungus Aspergillus westerdijkiae. BMC Genomics 2016; 17:633. [PMID: 27527502 PMCID: PMC4986183 DOI: 10.1186/s12864-016-2974-x] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Accepted: 07/28/2016] [Indexed: 01/13/2023] Open
Abstract
BACKGROUND Aspergillus westerdijkiae produces ochratoxin A (OTA) in Aspergillus section Circumdati. It is responsible for the contamination of agricultural crops, fruits, and food commodities, as its secondary metabolite OTA poses a potential threat to animals and humans. As a member of the filamentous fungi family, its capacity for enzymatic catalysis and secondary metabolite production is valuable in industrial production and medicine. To understand the genetic factors underlying its pathogenicity, enzymatic degradation, and secondary metabolism, we analysed the whole genome of A. westerdijkiae and compared it with eight other sequenced Aspergillus species. RESULTS We sequenced the complete genome of A. westerdijkiae and assembled approximately 36 Mb of its genomic DNA, in which we identified 10,861 putative protein-coding genes. We constructed a phylogenetic tree of A. westerdijkiae and eight other sequenced Aspergillus species and found that the sister group of A. westerdijkiae was the A. oryzae - A. flavus clade. By searching the associated databases, we identified 716 cytochrome P450 enzymes, 633 carbohydrate-active enzymes, and 377 proteases. By combining comparative analysis with Kyoto Encyclopaedia of Genes and Genomes (KEGG), Conserved Domains Database (CDD), and Pfam annotations, we predicted 228 potential carbohydrate-active enzymes related to plant polysaccharide degradation (PPD). We found a large number of secondary biosynthetic gene clusters, which suggested that A. westerdijkiae had a remarkable capacity to produce secondary metabolites. Furthermore, we obtained two more reliable and integrated gene sequences containing the reported portions of OTA biosynthesis and identified their respective secondary metabolite clusters. We also systematically annotated these two hybrid t1pks-nrps gene clusters involved in OTA biosynthesis. These two clusters were separate in the genome, and one of them encoded a couple of GH3 and AA3 enzyme genes involved in sucrose and glucose metabolism. CONCLUSIONS The genomic information obtained in this study is valuable for understanding the life cycle and pathogenicity of A. westerdijkiae. We identified numerous enzyme genes that are potentially involved in host invasion and pathogenicity, and we provided a preliminary prediction for each putative secondary metabolite (SM) gene cluster. In particular, for the OTA-related SM gene clusters, we delivered their components with domain and pathway annotations. This study sets the stage for experimental verification of the biosynthetic and regulatory mechanisms of OTA and for the discovery of new secondary metabolites.
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Affiliation(s)
- Xiaolong Han
- State Key Laboratory of Organ Failure Research, Division of Nephrology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province, People's Republic of China
- Department of Bioinformatics, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong Province, People's Republic of China
| | - Alolika Chakrabortti
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, Republic of Singapore
| | - Jindong Zhu
- State Key Laboratory of Organ Failure Research, Division of Nephrology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province, People's Republic of China
- Department of Bioinformatics, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong Province, People's Republic of China
| | - Zhao-Xun Liang
- School of Biological Sciences, Nanyang Technological University, 60 Nanyang Drive, Singapore, Republic of Singapore.
| | - Jinming Li
- State Key Laboratory of Organ Failure Research, Division of Nephrology, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong Province, People's Republic of China.
- Department of Bioinformatics, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong Province, People's Republic of China.
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36
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Baccile JA, Spraker JE, Le HH, Brandenburger E, Gomez C, Bok JW, Macheleidt J, Brakhage AA, Hoffmeister D, Keller NP, Schroeder FC. Plant-like biosynthesis of isoquinoline alkaloids in Aspergillus fumigatus. Nat Chem Biol 2016; 12:419-24. [PMID: 27065235 PMCID: PMC5049701 DOI: 10.1038/nchembio.2061] [Citation(s) in RCA: 61] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2015] [Accepted: 02/22/2016] [Indexed: 01/09/2023]
Abstract
Natural product discovery efforts have focused primarily on microbial biosynthetic gene clusters (BGCs) containing large multi-modular PKSs and NRPSs; however, sequencing of fungal genomes has revealed a vast number of BGCs containing smaller NRPS-like genes of unknown biosynthetic function. Using comparative metabolomics, we show that a BGC in the human pathogen Aspergillus fumigatus named fsq, which contains an NRPS-like gene lacking a condensation domain, produces several novel isoquinoline alkaloids, the fumisoquins. These compounds derive from carbon-carbon bond formation between two amino acid-derived moieties followed by a sequence that is directly analogous to isoquinoline alkaloid biosynthesis in plants. Fumisoquin biosynthesis requires the N-methyltransferase FsqC and the FAD-dependent oxidase FsqB, which represent functional analogs of coclaurine N-methyltransferase and berberine bridge enzyme in plants. Our results show that BGCs containing incomplete NRPS modules may reveal new biosynthetic paradigms and suggest that plant-like isoquinoline biosynthesis occurs in diverse fungi.
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Affiliation(s)
- Joshua A Baccile
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York, USA
| | - Joseph E Spraker
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Henry H Le
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York, USA
| | - Eileen Brandenburger
- Department of Pharmaceutical Microbiology at the Hans-Knöll-Institute, Friedrich Schiller University, Jena, Germany
| | - Christian Gomez
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York, USA
| | - Jin Woo Bok
- Institute for Microbiology, Friedrich Schiller University, Jena, Germany
| | - Juliane Macheleidt
- Institute for Microbiology, Friedrich Schiller University, Jena, Germany.,Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Jena, Germany
| | - Axel A Brakhage
- Institute for Microbiology, Friedrich Schiller University, Jena, Germany.,Molecular and Applied Microbiology, Leibniz Institute for Natural Product Research and Infection Biology (HKI), Jena, Germany
| | - Dirk Hoffmeister
- Department of Pharmaceutical Microbiology at the Hans-Knöll-Institute, Friedrich Schiller University, Jena, Germany
| | - Nancy P Keller
- Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin, USA.,Department of Medical Microbiology and Immunology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Frank C Schroeder
- Boyce Thompson Institute and Department of Chemistry and Chemical Biology, Cornell University, Ithaca, New York, USA
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37
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Moloney NM, Owens RA, Meleady P, Henry M, Dolan SK, Mulvihill E, Clynes M, Doyle S. The iron-responsive microsomal proteome of Aspergillus fumigatus. J Proteomics 2016; 136:99-111. [DOI: 10.1016/j.jprot.2015.12.025] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2015] [Revised: 12/02/2015] [Accepted: 12/23/2015] [Indexed: 01/17/2023]
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38
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Frisvad JC, Larsen TO. Extrolites of Aspergillus fumigatus and Other Pathogenic Species in Aspergillus Section Fumigati. Front Microbiol 2016; 6:1485. [PMID: 26779142 PMCID: PMC4703822 DOI: 10.3389/fmicb.2015.01485] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2015] [Accepted: 12/09/2015] [Indexed: 11/13/2022] Open
Abstract
Aspergillus fumigatus is an important opportunistic human pathogen known for its production of a large array of extrolites. Up to 63 species have been described in Aspergillus section Fumigati, some of which have also been reliably reported to be pathogenic, including A. felis, A. fischeri, A. fumigatiaffinis, A. fumisynnematus, A. hiratsukae, A. laciniosus, A. lentulus, A. novofumigatus, A. parafelis, A. pseudofelis, A. pseudoviridinutans, A. spinosus, A. thermomutatus, and A. udagawae. These species share the production of hydrophobins, melanins, and siderophores and ability to grow well at 37°C, but they only share some small molecule extrolites, that could be important factors in pathogenicity. According to the literature gliotoxin and other exometabolites can be contributing factors to pathogenicity, but these exometabolites are apparently not produced by all pathogenic species. It is our hypothesis that species unable to produce some of these metabolites can produce proxy-exometabolites that may serve the same function. We tabulate all exometabolites reported from species in Aspergillus section Fumigati and by comparing the profile of those extrolites, suggest that those producing many different kinds of exometabolites are potential opportunistic pathogens. The exometabolite data also suggest that the profile of exometabolites are highly specific and can be used for identification of these closely related species.
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Affiliation(s)
- Jens C. Frisvad
- Section of Eukaryotic Biotechnology, Department of Systems Biology, Technical University of DenmarkKongens Lyngby, Denmark
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39
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Wang PM, Choera T, Wiemann P, Pisithkul T, Amador-Noguez D, Keller NP. TrpE feedback mutants reveal roadblocks and conduits toward increasing secondary metabolism in Aspergillus fumigatus. Fungal Genet Biol 2015; 89:102-113. [PMID: 26701311 DOI: 10.1016/j.fgb.2015.12.002] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2015] [Revised: 11/23/2015] [Accepted: 12/05/2015] [Indexed: 12/11/2022]
Abstract
Small peptides formed from non-ribosomal peptide synthetases (NRPS) are bioactive molecules produced by many fungi including the genus Aspergillus. A subset of NRPS utilizes tryptophan and its precursor, the non-proteinogenic amino acid anthranilate, in synthesis of various metabolites such as Aspergillus fumigatus fumiquinazolines (Fqs) produced by the fmq gene cluster. The A. fumigatus genome contains two putative anthranilate synthases - a key enzyme in conversion of anthranilic acid to tryptophan - one beside the fmq cluster and one in a region of co-linearity with other Aspergillus spp. Only the gene found in the co-linear region, trpE, was involved in tryptophan biosynthesis. We found that site-specific mutations of the TrpE feedback domain resulted in significantly increased production of anthranilate, tryptophan, p-aminobenzoate and fumiquinazolines FqF and FqC. Supplementation with tryptophan restored metabolism to near wild type levels in the feedback mutants and suggested that synthesis of the tryptophan degradation product kynurenine could negatively impact Fq synthesis. The second putative anthranilate synthase gene next to the fmq cluster was termed icsA for its considerable identity to isochorismate synthases in bacteria. Although icsA had no impact on A. fumigatus Fq production, deletion and over-expression of icsA increased and decreased respectively aromatic amino acid levels suggesting that IcsA can draw from the cellular chorismate pool.
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Affiliation(s)
- Pin-Mei Wang
- Ocean College, Zhejiang University, Hangzhou 310058, Zhejiang Province, PR China
| | - Tsokyi Choera
- Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, USA
| | - Philipp Wiemann
- Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, USA
| | | | | | - Nancy P Keller
- Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, USA; Department of Bacteriology, University of Wisconsin, Madison, USA.
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40
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Keller NP. Translating biosynthetic gene clusters into fungal armor and weaponry. Nat Chem Biol 2015; 11:671-7. [PMID: 26284674 DOI: 10.1038/nchembio.1897] [Citation(s) in RCA: 177] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2015] [Accepted: 07/23/2015] [Indexed: 01/06/2023]
Abstract
Filamentous fungi are renowned for the production of a diverse array of secondary metabolites (SMs) where the genetic material required for synthesis of a SM is typically arrayed in a biosynthetic gene cluster (BGC). These natural products are valued for their bioactive properties stemming from their functions in fungal biology, key among those protection from abiotic and biotic stress and establishment of a secure niche. The producing fungus must not only avoid self-harm from endogenous SMs but also deliver specific SMs at the right time to the right tissue requiring biochemical aid. This review highlights functions of BGCs beyond the enzymatic assembly of SMs, considering the timing and location of SM production and other proteins in the clusters that control SM activity. Specifically, self-protection is provided by both BGC-encoded mechanisms and non-BGC subcellular containment of toxic SM precursors; delivery and timing is orchestrated through cellular trafficking patterns and stress- and developmental-responsive transcriptional programs.
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Affiliation(s)
- Nancy P Keller
- Department of Bacteriology and Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, Wisconsin, USA
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41
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Roelants SL, Ciesielska K, De Maeseneire SL, Moens H, Everaert B, Verweire S, Denon Q, Vanlerberghe B, Van Bogaert IN, Van der Meeren P, Devreese B, Soetaert W. Towards the industrialization of new biosurfactants: Biotechnological opportunities for the lactone esterase gene fromStarmerella bombicola. Biotechnol Bioeng 2015; 113:550-9. [DOI: 10.1002/bit.25815] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2015] [Revised: 08/18/2015] [Accepted: 08/20/2015] [Indexed: 11/11/2022]
Affiliation(s)
- Sophie L.K.W. Roelants
- Centre for Industrial Biotechnology and Biocatalysis (InBio.be); Faculty of Bioscience Engineering, Ghent University; Coupure Links 653 9000 Ghent Belgium
- Bio Base Europe Pilot Plant (BBEU); Rodenhuizekaai 1; 9042 Ghent (Desteldonk) Belgium
| | - Katarzyna Ciesielska
- L-Probe, Department of Sciences; Ghent University; K.L. Ledeganckstraat 35 9000 Ghent Belgium
| | - Sofie L. De Maeseneire
- Centre for Industrial Biotechnology and Biocatalysis (InBio.be); Faculty of Bioscience Engineering, Ghent University; Coupure Links 653 9000 Ghent Belgium
| | - Helena Moens
- Bio Base Europe Pilot Plant (BBEU); Rodenhuizekaai 1; 9042 Ghent (Desteldonk) Belgium
| | - Bernd Everaert
- Bio Base Europe Pilot Plant (BBEU); Rodenhuizekaai 1; 9042 Ghent (Desteldonk) Belgium
| | - Stijn Verweire
- Centre for Industrial Biotechnology and Biocatalysis (InBio.be); Faculty of Bioscience Engineering, Ghent University; Coupure Links 653 9000 Ghent Belgium
| | - Quenten Denon
- Particle and Interfacial Technology Group; Department of Applied Analytical and Physical Chemistry; Faculty of Bioscience Engineering; Ghent University; Coupure Links 653 9000 Ghent Belgium
| | - Brecht Vanlerberghe
- Bio Base Europe Pilot Plant (BBEU); Rodenhuizekaai 1; 9042 Ghent (Desteldonk) Belgium
| | - Inge N.A. Van Bogaert
- Centre for Industrial Biotechnology and Biocatalysis (InBio.be); Faculty of Bioscience Engineering, Ghent University; Coupure Links 653 9000 Ghent Belgium
| | - Paul Van der Meeren
- Particle and Interfacial Technology Group; Department of Applied Analytical and Physical Chemistry; Faculty of Bioscience Engineering; Ghent University; Coupure Links 653 9000 Ghent Belgium
| | - Bart Devreese
- L-Probe, Department of Sciences; Ghent University; K.L. Ledeganckstraat 35 9000 Ghent Belgium
| | - Wim Soetaert
- Centre for Industrial Biotechnology and Biocatalysis (InBio.be); Faculty of Bioscience Engineering, Ghent University; Coupure Links 653 9000 Ghent Belgium
- Bio Base Europe Pilot Plant (BBEU); Rodenhuizekaai 1; 9042 Ghent (Desteldonk) Belgium
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Abstract
A fungus called Aspergillus terreus produces a secondary metabolite in response to various environmental signals to give it an advantage over its competitors.
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Affiliation(s)
- Hubertus Haas
- Division of Molecular Biology, Biocenter, Medical University of Innsbruck, Innsbruck, Austria
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43
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Sheridan KJ, Dolan SK, Doyle S. Endogenous cross-talk of fungal metabolites. Front Microbiol 2015; 5:732. [PMID: 25601857 PMCID: PMC4283610 DOI: 10.3389/fmicb.2014.00732] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2014] [Accepted: 12/04/2014] [Indexed: 12/21/2022] Open
Abstract
Non-ribosomal peptide (NRP) synthesis in fungi requires a ready supply of proteogenic and non-proteogenic amino acids which are subsequently incorporated into the nascent NRP via a thiotemplate mechanism catalyzed by NRP synthetases. Substrate amino acids can be modified prior to or during incorporation into the NRP, or following incorporation into an early stage amino acid-containing biosynthetic intermediate. These post-incorporation modifications involve a range of additional enzymatic activities including but not exclusively, monooxygenases, methyltransferases, epimerases, oxidoreductases, and glutathione S-transferases which are essential to effect biosynthesis of the final NRP. Likewise, polyketide biosynthesis is directly by polyketide synthase megaenzymes and cluster-encoded ancillary decorating enzymes. Additionally, a suite of additional primary metabolites, for example: coenzyme A (CoA), acetyl CoA, S-adenosylmethionine, glutathione (GSH), NADPH, malonyl CoA, and molecular oxygen, amongst others are required for NRP and polyketide synthesis (PKS). Clearly these processes must involve exquisite orchestration to facilitate the simultaneous biosynthesis of different types of NRPs, polyketides, and related metabolites requiring identical or similar biosynthetic precursors or co-factors. Moreover, the near identical structures of many natural products within a given family (e.g., ergot alkaloids), along with localization to similar regions within fungi (e.g., conidia) suggests that cross-talk may exist, in terms of biosynthesis and functionality. Finally, we speculate if certain biosynthetic steps involved in NRP and PKS play a role in cellular protection or environmental adaptation, and wonder if these enzymatic reactions are of equivalent importance to the actual biosynthesis of the final metabolite.
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Affiliation(s)
| | - Stephen K Dolan
- Department of Biology, Maynooth University Maynooth, Ireland
| | - Sean Doyle
- Department of Biology, Maynooth University Maynooth, Ireland
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