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Chakraborty A, Alsharqi L, Kostrzewa M, Armstrong-James D, Larrouy-Maumus G. Intact cell lipidomics using the Bruker MBT lipid Xtract assay allows the rapid detection of glycosyl-inositol-phospho-ceramides from Aspergillus fumigatus. Mol Omics 2024; 20:390-396. [PMID: 38623711 DOI: 10.1039/d4mo00030g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/17/2024]
Abstract
Glycosyl-inositol-phospho-ceramides (GIPCs) or glycosylphosphatidylinositol-anchored fungal polysaccharides are major lipids in plant and fungal plasma membranes and play an important role in stress adaption. However, their analysis remains challenging due to the multiple steps involved in their extraction and purification prior to mass spectrometry analysis. To address this challenge, we report here a novel simplified method to identify GIPCs from Aspergillus fumigatus using the new Bruker MBT lipid Xtract assay. A. fumigatus reference strains and clinical isolates were cultured, harvested, heat-inactivated and suspended in double-distilled water. A fraction of this fungal preparation was then dried in a microtube, mixed with an MBT lipid Xtract matrix (Bruker Daltonik, Germany) and loaded onto a MALDI target plate. Analysis was performed using a Bruker MALDI Biotyper Sirius system in the linear negative ion mode. Mass spectra were scanned from m/z 700 to m/z 2 000. MALDI-TOF MS analysis of cultured fungi showed a clear signature of GIPCs in Aspergillus fumigatus reference strains and clinical isolates. Here, we have demonstrated that routine MALDI-TOF in the linear negative ion mode combined with the MBT lipid Xtract is able to detect Aspergillus fumigatus GIPCs.
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Affiliation(s)
- Aishani Chakraborty
- Centre for Bacterial Resistance Biology, Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, SW7 2AZ, UK.
| | - Leila Alsharqi
- Centre for Bacterial Resistance Biology, Department of Infectious Diseases, Faculty of Medicine, Imperial College London, London, SW7 2AZ, UK.
| | | | - Darius Armstrong-James
- Centre for Bacterial Resistance Biology, Department of Infectious Diseases, Faculty of Medicine, Imperial College London, London, SW7 2AZ, UK.
| | - Gerald Larrouy-Maumus
- Centre for Bacterial Resistance Biology, Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, SW7 2AZ, UK.
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Kadooka C, Tanaka Y, Kishida R, Hira D, Oka T. Discovery of α-(1→6)-linked mannan structures resembling yeast N-glycan outer chains in Aspergillus fumigatus mycelium. mSphere 2024; 9:e0010024. [PMID: 38651868 DOI: 10.1128/msphere.00100-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2024] [Accepted: 03/26/2024] [Indexed: 04/25/2024] Open
Abstract
The cellular surface of the pathogenic filamentous fungus Aspergillus fumigatus is enveloped in a mannose layer, featuring well-established fungal-type galactomannan and O-mannose-type galactomannan. This study reports the discovery of cell wall component in A. fumigatus mycelium, which resembles N-glycan outer chains found in yeast. The glycosyltransferases involved in its biosynthesis in A. fumigatus were identified, with a focus on two key α-(1→2)-mannosyltransferases, Mnn2 and Mnn5, and two α-(1→6)-mannosyltransferases, Mnn9 and Van1. In vitro examination revealed the roles of recombinant Mnn2 and Mnn5 in transferring α-(1→2)-mannosyl residues. Proton nuclear magnetic resonance (1H-NMR) analysis of cell wall extracts from the ∆mnn2∆mnn5 strain indicated the existence of an α-(1→6)-linked mannan backbone in the A. fumigatus mycelium, with Mnn2 and Mnn5 adding α-(1→2)-mannosyl residues to this backbone. The α-(1→6)-linked mannan backbone was absent in strains where mnn9 or van1 was disrupted in the parental ∆mnn2∆mnn5 strain in A. fumigatus. Mnn9 and Van1 functioned as α-(1→6)-linked mannan polymerases in heterodimers when co-expressed in Escherichia coli, indicating their crucial role in biosynthesizing the α-(1→6)-linked mannan backbone. Disruptions of these mannosyltransferases did not affect fungal-type galactomannan biosynthesis. This study provides insights into the complexity of fungal cell wall architecture and a better understanding of mannan biosynthesis in A. fumigatus. IMPORTANCE This study unravels the complexities of mannan biosynthesis in A. fumigatus, a key area for antifungal drug discovery. It reveals the presence of α-(1→6)-linked mannan structures resembling yeast N-glycan outer chains in A. fumigatus mycelium, offering fresh insights into the fungal cell wall's design. Key enzymes, Mnn2, Mnn5, Mnn9, and Van1, are instrumental in this process, with Mnn2 and Mnn5 adding specific mannose residues and Mnn9 and Van1 assembling the α-(1→6)-linked mannan structures. Although fungal-type galactomannan's presence in the cell wall is known, the existence of an α-(1→6)-linked mannan adds a new dimension to our understanding. This intricate web of mannan biosynthesis opens avenues for further exploration and enhances our understanding of fungal cell wall dynamics, paving the way for targeted drug development.
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Affiliation(s)
- Chihiro Kadooka
- Department of Biotechnology and Life Sciences, Faculty of Biotechnology and Life Sciences, Sojo University, Kumamoto, Japan
| | - Yutaka Tanaka
- Division of Infection and Host Defense, Tohoku Medical and Pharmaceutical University, Sendai, Japan
| | - Rintaro Kishida
- Department of Biotechnology and Life Sciences, Faculty of Biotechnology and Life Sciences, Sojo University, Kumamoto, Japan
| | - Daisuke Hira
- Department of Biotechnology and Life Sciences, Faculty of Biotechnology and Life Sciences, Sojo University, Kumamoto, Japan
| | - Takuji Oka
- Department of Biotechnology and Life Sciences, Faculty of Biotechnology and Life Sciences, Sojo University, Kumamoto, Japan
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Zhao W, Debnath D, Gautam I, Fernando LD, Wang T. Charting the solid-state NMR signals of polysaccharides: A database-driven roadmap. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2024; 62:298-309. [PMID: 37724740 DOI: 10.1002/mrc.5397] [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: 05/14/2023] [Revised: 09/01/2023] [Accepted: 09/07/2023] [Indexed: 09/21/2023]
Abstract
Solid-state nuclear magnetic resonance (ssNMR) measurements of intact cell walls and cellular samples often generate spectra that are difficult to interpret due to the presence of many coexisting glycans and the structural polymorphism observed in native conditions. To overcome this analytical challenge, we present a statistical approach for analyzing carbohydrate signals using high-resolution ssNMR data indexed in a carbohydrate database. We generate simulated spectra to demonstrate the chemical shift dispersion and compare this with experimental data to facilitate the identification of important fungal and plant polysaccharides, such as chitin and glucans in fungi and cellulose, hemicellulose, and pectic polymers in plants. We also demonstrate that chemically distinct carbohydrates from different organisms may produce almost identical signals, highlighting the need for high-resolution spectra and validation of resonance assignments. Our study provides a means to differentiate the characteristic signals of major carbohydrates and allows us to summarize currently undetected polysaccharides in plants and fungi, which may inspire future investigations.
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Affiliation(s)
- Wancheng Zhao
- Department of Chemistry, Michigan State University, East Lansing, Michigan, USA
| | - Debkumar Debnath
- Department of Chemistry, Michigan State University, East Lansing, Michigan, USA
| | - Isha Gautam
- Department of Chemistry, Michigan State University, East Lansing, Michigan, USA
| | - Liyanage D Fernando
- Department of Chemistry, Michigan State University, East Lansing, Michigan, USA
| | - Tuo Wang
- Department of Chemistry, Michigan State University, East Lansing, Michigan, USA
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Banz M, Stallmach A, Gaßler N, Schulze PC, Fritzenwanger M, Cornely O, Kurzai O, Pletz MW. Fatal pulmonary hemorrhage, pneumothorax and skin necrosis caused by IRIS to an Aspergillus flavus infection in a young patient with metamizole associated agranulocytosis. Infection 2024; 52:685-690. [PMID: 38133714 PMCID: PMC10955021 DOI: 10.1007/s15010-023-02149-x] [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: 10/11/2023] [Accepted: 11/27/2023] [Indexed: 12/23/2023]
Abstract
We report the case of a young female with steroid-dependent ulcerative colitis (UC) who developed a complex systemic infection with Aspergillus flavus. This occurred following a UC relapse while vacationing in the Middle East, leading to extended use of metamizole and subsequent agranulocytosis. On her return to Germany, she was hospitalized for neutropenic sepsis and later transferred to our hospital due to persistent cytopenia and suspected Hemophagocytic Lymphohistiocytosis (HLH). Despite initial stabilization with targeted treatment for pulmonary Aspergillus flavus infection, her condition rapidly deteriorated following the onset of an Immune Reconstitution Inflammatory Syndrome (IRIS), which manifested as skin necrosis and pneumothorax after the replenishment of neutrophil granulocytes. The patient eventually died from an unmanageable pulmonary hemorrhage. Microscopy of skin necroses showed a massive presence of Aspergillus flavus, but tissue culture remained negative, suggesting effective antifungal treatment yet delayed phagocytosis due to agranulocytosis. This case underscores the need to consider IRIS in immunosuppressed patients who worsen despite aggressive and appropriately targeted treatment, highlighting its potential beyond the commonly recognized context in HIV-positive patients.
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Affiliation(s)
- Micha Banz
- Institute of Infectious Diseases and Infection Control, Jena University Hospital, Jena, Germany.
| | - Andreas Stallmach
- Department of Gastroenterology, Hepatology and Infectology, Jena University Hospital, Jena, Germany
| | - Nikolaus Gaßler
- Institute of Pathology, Jena University Hospital, Jena, Germany
| | - P Christian Schulze
- Department of Cardiology, Angiology, and Pulmonology, Jena University Hospital, Jena, Germany
| | - Michael Fritzenwanger
- Department of Cardiology, Angiology, and Pulmonology, Jena University Hospital, Jena, Germany
| | - Oliver Cornely
- Department I of Internal Medicine, Faculty of Medicine and University Hospital Cologne, Excellence Center for Medical Mycology, Cologne, Germany
| | - Oliver Kurzai
- Institute for Hygiene and Microbiology, University of Würzburg, Würzburg, Germany
| | - Mathias W Pletz
- Institute of Infectious Diseases and Infection Control, Jena University Hospital, Jena, Germany
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Shankar J, Thakur R, Clemons KV, Stevens DA. Interplay of Cytokines and Chemokines in Aspergillosis. J Fungi (Basel) 2024; 10:251. [PMID: 38667922 PMCID: PMC11051073 DOI: 10.3390/jof10040251] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2024] [Revised: 03/11/2024] [Accepted: 03/25/2024] [Indexed: 04/28/2024] Open
Abstract
Aspergillosis is a fungal infection caused by various species of Aspergillus, most notably A. fumigatus. This fungus causes a spectrum of diseases, including allergic bronchopulmonary aspergillosis, aspergilloma, chronic pulmonary aspergillosis, and invasive aspergillosis. The clinical manifestations and severity of aspergillosis can vary depending on individual immune status and the specific species of Aspergillus involved. The recognition of Aspergillus involves pathogen-associated molecular patterns (PAMPs) such as glucan, galactomannan, mannose, and conidial surface proteins. These are recognized by the pathogen recognition receptors present on immune cells such as Toll-like receptors (TLR-1,2,3,4, etc.) and C-type lectins (Dectin-1 and Dectin-2). We discuss the roles of cytokines and pathogen recognition in aspergillosis from both the perspective of human and experimental infection. Several cytokines and chemokines have been implicated in the immune response to Aspergillus infection, including interferon-γ (IFN-γ), tumor necrosis factor-α (TNF-α), CCR4, CCR17, and other interleukins. For example, allergic bronchopulmonary aspergillosis (ABPA) is characterized by Th2 and Th9 cell-type immunity and involves interleukin (IL)-4, IL-5, IL-13, and IL-10. In contrast, it has been observed that invasive aspergillosis involves Th1 and Th17 cell-type immunity via IFN-γ, IL-1, IL-6, and IL-17. These cytokines activate various immune cells and stimulate the production of other immune molecules, such as antimicrobial peptides and reactive oxygen species, which aid in the clearance of the fungal pathogen. Moreover, they help to initiate and coordinate the immune response, recruit immune cells to the site of infection, and promote clearance of the fungus. Insight into the host response from both human and animal studies may aid in understanding the immune response in aspergillosis, possibly leading to harnessing the power of cytokines or cytokine (receptor) antagonists and transforming them into precise immunotherapeutic strategies. This could advance personalized medicine.
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Affiliation(s)
- Jata Shankar
- Genomic Laboratory, Department of Biotechnology and Bioinformatics, Jaypee University of Information Technology, Waknaghat Solan 173234, Himachal Pradesh, India
| | - Raman Thakur
- Department of Medical Laboratory Science, Lovely Professional University, Jalandhar 144001, Punjab, India;
| | - Karl V. Clemons
- California Institute for Medical Research, San Jose, CA 95128, USA; (K.V.C.); (D.A.S.)
- Division of Infectious Diseases and Geographic Medicine, Stanford University Medical School, Stanford, CA 94305, USA
| | - David A. Stevens
- California Institute for Medical Research, San Jose, CA 95128, USA; (K.V.C.); (D.A.S.)
- Division of Infectious Diseases and Geographic Medicine, Stanford University Medical School, Stanford, CA 94305, USA
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Fernando LD, Pérez-Llano Y, Dickwella Widanage MC, Jacob A, Martínez-Ávila L, Lipton AS, Gunde-Cimerman N, Latgé JP, Batista-García RA, Wang T. Structural adaptation of fungal cell wall in hypersaline environment. Nat Commun 2023; 14:7082. [PMID: 37925437 PMCID: PMC10625518 DOI: 10.1038/s41467-023-42693-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 10/18/2023] [Indexed: 11/06/2023] Open
Abstract
Halophilic fungi thrive in hypersaline habitats and face a range of extreme conditions. These fungal species have gained considerable attention due to their potential applications in harsh industrial processes, such as bioremediation and fermentation under unfavorable conditions of hypersalinity, low water activity, and extreme pH. However, the role of the cell wall in surviving these environmental conditions remains unclear. Here we employ solid-state NMR spectroscopy to compare the cell wall architecture of Aspergillus sydowii across salinity gradients. Analyses of intact cells reveal that A. sydowii cell walls contain a rigid core comprising chitin, β-glucan, and chitosan, shielded by a surface shell composed of galactomannan and galactosaminogalactan. When exposed to hypersaline conditions, A. sydowii enhances chitin biosynthesis and incorporates α-glucan to create thick, stiff, and hydrophobic cell walls. Such structural rearrangements enable the fungus to adapt to both hypersaline and salt-deprived conditions, providing a robust mechanism for withstanding external stress. These molecular principles can aid in the optimization of halophilic strains for biotechnology applications.
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Affiliation(s)
- Liyanage D Fernando
- Department of Chemistry, Michigan State University, East Lansing, MI, USA
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, 30602, USA
| | - Yordanis Pérez-Llano
- Centro de Investigación en Dinámica Celular, Universidad Autónoma del Estado de Morelos, Cuernavaca, Mexico
| | - Malitha C Dickwella Widanage
- Department of Chemistry, Michigan State University, East Lansing, MI, USA
- Department of Chemistry, University of Michigan, Ann Arbor, MI, 48109, USA
| | - Anand Jacob
- Department of Chemistry, Michigan State University, East Lansing, MI, USA
| | - Liliana Martínez-Ávila
- Centro de Investigación en Dinámica Celular, Universidad Autónoma del Estado de Morelos, Cuernavaca, Mexico
| | - Andrew S Lipton
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA, USA
| | | | - Jean-Paul Latgé
- Institute of Molecular Biology and Biotechnology, University of Crete, Heraklion, Greece
- Fungal Respiratory Infections Research Unit, University of Angers, Angers, France
| | | | - Tuo Wang
- Department of Chemistry, Michigan State University, East Lansing, MI, USA.
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Sabbah R, Korem M, Shaulov A, Aumann S, Nachmias B. Utility of Galactomannan Screening for Early Detection of Invasive Aspergillosis in High-Risk Hemato-Oncology Patients. Acta Haematol 2023; 146:358-365. [PMID: 37231768 PMCID: PMC10614280 DOI: 10.1159/000531044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 05/06/2023] [Indexed: 05/27/2023]
Abstract
INTRODUCTION Invasive aspergillosis (IA) affects mainly patients with hematological malignancies, and early diagnosis is crucial for timely treatment. Most diagnoses are based on clinical and mycological criteria, mostly galactomannan (GM) test in serum or bronchoalveolar fluid, which is performed in case of clinical suspicion or as routine screening in patients at high risk who are not receiving anti-mold prophylaxis, for early detection of IA. The aim of this study was to assess in a real-world setting the efficacy of biweekly serum GM screening for the early detection of IA. METHODS A retrospective cohort that included 80 adult patients treated at the Hematology Department, Hadassah Medical Center, 2016-2020, with a diagnosis of IA. Clinical and laboratory data were collected from patients' medical files and the rate of GM-driven, GM-associated, and non-GM-associated IA was calculated. RESULTS There were 58 patients with IA. The rate of GM-driven diagnosis was 6.9%, GM-associated diagnosis was 43.1%, and non-GM-associated diagnosis was 56.9%. The GM test as a screening tool had led to IA diagnosis in only 0.2% of screened serums with a number needed to screen in order to find 1 patient with IA of 490. CONCLUSION Clinical suspicion outweighs GM screening as a tool for early diagnosis of IA. Nevertheless, GM has an important role as a diagnostic tool for IA.
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Affiliation(s)
- Rozan Sabbah
- School of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Maya Korem
- Department of Microbiology and Infectious Diseases, Hadassah Medical Center and Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Adir Shaulov
- Department of Hematology, Hadassah Medical Center and Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Shlomzion Aumann
- Department of Hematology, Hadassah Medical Center and Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
| | - Boaz Nachmias
- Department of Hematology, Hadassah Medical Center and Faculty of Medicine, Hebrew University of Jerusalem, Jerusalem, Israel
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Approach to the diagnosis of invasive fungal infections of the respiratory tract in the immunocompromised host. Curr Opin Pulm Med 2023; 29:149-159. [PMID: 36917216 DOI: 10.1097/mcp.0000000000000955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/15/2023]
Abstract
PURPOSE OF REVIEW The burden of invasive fungal infection is increasing worldwide, largely due to a growing population at-risk. Most serious human fungal pathogens enter the host via the respiratory tract. Early identification and treatment of invasive fungal respiratory infections (IFRIs) in the immunocompromised host saves lives. However, their accurate diagnosis is a difficult challenge for clinicians and mortality remains high. RECENT FINDINGS This article reviews IFRIs, focussing on host susceptibility factors, clinical presentation, and mycological diagnosis. Several new diagnostic tools are coming of age including molecular diagnostics and point-of-care antigen tests. As diagnosis of IFRI relies heavily on invasive procedures like bronchoalveolar lavage and lung biopsy, several novel noninvasive diagnostic techniques are in development, such as metagenomics, 'volatilomics' and advanced imaging technologies. SUMMARY Where IFRI cannot be proven, clinicians must employ a 'weights-of-evidence' approach to evaluate host factors, clinical and mycological data. Implementation studies are needed to understand how new diagnostic tools can be best applied within clinical pathways. Differentiating invasive infection from colonization and identifying antifungal resistance remain key challenges. As our diagnostic arsenal expands, centralized clinical mycology laboratories and efforts to ensure access to new diagnostics in low-resource settings will become increasingly important.
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Reedy JL, Crossen AJ, Negoro PE, Harding HB, Ward RA, Vargas-Blanco DA, Timmer KD, Reardon CM, Basham KJ, Mansour MK, Wüthrich M, Fontaine T, Latgé JP, Vyas JM. The C-Type Lectin Receptor Dectin-2 Is a Receptor for Aspergillus fumigatus Galactomannan. mBio 2023; 14:e0318422. [PMID: 36598192 PMCID: PMC9973300 DOI: 10.1128/mbio.03184-22] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Accepted: 11/21/2022] [Indexed: 01/05/2023] Open
Abstract
Aspergillus fumigatus is a ubiquitous environmental mold that causes significant mortality particularly among immunocompromised patients. The detection of the Aspergillus-derived carbohydrate galactomannan in patient serum and bronchoalveolar lavage fluid is the major biomarker used to detect A. fumigatus infection in clinical medicine. Despite the clinical relevance of this carbohydrate, we lack a fundamental understanding of how galactomannan is recognized by the immune system and its consequences. Galactomannan is composed of a linear mannan backbone with galactofuranose sidechains and is found both attached to the cell surface of Aspergillus and as a soluble carbohydrate in the extracellular milieu. In this study, we utilized fungal-like particles composed of highly purified Aspergillus galactomannan to identify a C-type lectin host receptor for this fungal carbohydrate. We identified a novel and specific interaction between Aspergillus galactomannan and the C-type lectin receptor Dectin-2. We demonstrate that galactomannan bound to Dectin-2 and induced Dectin-2-dependent signaling, including activation of spleen tyrosine kinase, gene transcription, and tumor necrosis factor alpha (TNF-α) production. Deficiency of Dectin-2 increased immune cell recruitment to the lungs but was dispensable for survival in a mouse model of pulmonary aspergillosis. Our results identify a novel interaction between galactomannan and Dectin-2 and demonstrate that Dectin-2 is a receptor for galactomannan, which leads to a proinflammatory immune response in the lung. IMPORTANCE Aspergillus fumigatus is a fungal pathogen that causes serious and often fatal disease in humans. The surface of Aspergillus is composed of complex sugar molecules. Recognition of these carbohydrates by immune cells by carbohydrate lectin receptors can lead to clearance of the infection or, in some cases, benefit the fungus by dampening the host response. Galactomannan is a carbohydrate that is part of the cell surface of Aspergillus but is also released during infection and is found in patient lungs as well as their bloodstreams. The significance of our research is that we have identified Dectin-2 as a mammalian immune cell receptor that recognizes, binds, and signals in response to galactomannan. These results enhance our understanding of how this carbohydrate interacts with the immune system at the site of infection and will lead to broader understanding of how release of galactomannan by Aspergillus effects the immune response in infected patients.
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Affiliation(s)
- Jennifer L. Reedy
- Division of Infectious Diseases, Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA
- Harvard Medical School, Department of Medicine, Boston, Massachusetts, USA
| | - Arianne J. Crossen
- Division of Infectious Diseases, Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Paige E. Negoro
- Division of Infectious Diseases, Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Hannah Brown Harding
- Division of Infectious Diseases, Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Rebecca A. Ward
- Division of Infectious Diseases, Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Diego A. Vargas-Blanco
- Division of Infectious Diseases, Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Kyle D. Timmer
- Division of Infectious Diseases, Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Christopher M. Reardon
- Division of Infectious Diseases, Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Kyle J. Basham
- Division of Infectious Diseases, Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA
| | - Michael K. Mansour
- Division of Infectious Diseases, Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA
- Harvard Medical School, Department of Medicine, Boston, Massachusetts, USA
| | - Marcel Wüthrich
- Department of Pediatrics, University of Wisconsin Medical School, University of Wisconsin Hospital and Clinics, Madison, Wisconsin, USA
| | - Thierry Fontaine
- Institut Pasteur, Université de Paris, INRAE, USC2019, Unité Biologie et Pathogénicité Fongiques, Paris, France
| | - Jean-Paul Latgé
- Institute of Molecular Biology and Biotechnology (IMBBFORTH), University of Crete, Heraklion, Greece
| | - Jatin M. Vyas
- Division of Infectious Diseases, Department of Medicine, Massachusetts General Hospital, Boston, Massachusetts, USA
- Harvard Medical School, Department of Medicine, Boston, Massachusetts, USA
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10
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Kadooka C, Tanaka Y, Hira D, Maruyama JI, Goto M, Oka T. Identification of galactofuranose antigens such as galactomannoproteins and fungal-type galactomannan from the yellow koji fungus ( Aspergillus oryzae). Front Microbiol 2023; 14:1110996. [PMID: 36814571 PMCID: PMC9939772 DOI: 10.3389/fmicb.2023.1110996] [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: 11/29/2022] [Accepted: 01/16/2023] [Indexed: 02/08/2023] Open
Abstract
Filamentous fungi belonging to the genus Aspergillus are known to possess galactomannan in their cell walls. Galactomannan is highly antigenic to humans and has been reported to be involved in the pathogenicity of pathogenic filamentous fungi, such as A. fumigatus, and in immune responses. In this study, we aimed to confirm the presence of D-galactofuranose-containing glycans and to clarify the biosynthesis of D-galactofuranose-containing glycans in Aspergillus oryzae, a yellow koji fungus. We found that the galactofuranose antigen is also present in A. oryzae. Deletion of ugmA, which encodes UDP-galactopyranose mutase in A. oryzae, suppressed mycelial elongation, suggesting that D-galactofuranose-containing glycans play an important role in cell wall integrity in A. oryzae. Proton nuclear magnetic resonance spectrometry revealed that the galactofuranose-containing sugar chain was deficient and that core mannan backbone structures were present in ΔugmA A. oryzae, indicating the presence of fungal-type galactomannan in the cell wall fraction of A. oryzae. The findings of this study provide new insights into the cell wall structure of A. oryzae, which is essential for the production of fermented foods in Japan.
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Affiliation(s)
- Chihiro Kadooka
- Department of Biotechnology and Life Sciences, Faculty of Biotechnology and Life Sciences, Sojo University, Kumamoto, Japan
| | - Yutaka Tanaka
- Division of Infection and Host Defense, Tohoku Medical and Pharmaceutical University, Sendai, Japan
| | - Daisuke Hira
- Department of Biotechnology and Life Sciences, Faculty of Biotechnology and Life Sciences, Sojo University, Kumamoto, Japan
| | - Jun-ichi Maruyama
- Department of Biotechnology, The University of Tokyo, Tokyo, Japan,Collaborative Research Institute for Innovative Microbiology, The University of Tokyo, Tokyo, Japan
| | - Masatoshi Goto
- Department of Applied Biochemistry and Food Science, Faculty of Agriculture, Saga University, Saga, Japan
| | - Takuji Oka
- Department of Biotechnology and Life Sciences, Faculty of Biotechnology and Life Sciences, Sojo University, Kumamoto, Japan,*Correspondence: Takuji Oka,
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Liu Z, Valsecchi I, Le Meur RA, Simenel C, Guijarro JI, Comte C, Muszkieta L, Mouyna I, Henrissat B, Aimanianda V, Latgé JP, Fontaine T. Conidium Specific Polysaccharides in Aspergillus fumigatus. J Fungi (Basel) 2023; 9:jof9020155. [PMID: 36836270 PMCID: PMC9964227 DOI: 10.3390/jof9020155] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 01/09/2023] [Accepted: 01/19/2023] [Indexed: 01/27/2023] Open
Abstract
Earlier studies have shown that the outer layers of the conidial and mycelial cell walls of Aspergillus fumigatus are different. In this work, we analyzed the polysaccharidome of the resting conidial cell wall and observed major differences within the mycelium cell wall. Mainly, the conidia cell wall was characterized by (i) a smaller amount of α-(1,3)-glucan and chitin; (ii) a larger amount of β-(1,3)-glucan, which was divided into alkali-insoluble and water-soluble fractions, and (iii) the existence of a specific mannan with side chains containing galactopyranose, glucose, and N-acetylglucosamine residues. An analysis of A. fumigatus cell wall gene mutants suggested that members of the fungal GH-72 transglycosylase family play a crucial role in the conidia cell wall β-(1,3)-glucan organization and that α-(1,6)-mannosyltransferases of GT-32 and GT-62 families are essential to the polymerization of the conidium-associated cell wall mannan. This specific mannan and the well-known galactomannan follow two independent biosynthetic pathways.
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Affiliation(s)
- Zhonghua Liu
- Institut Pasteur, Unité des Aspergillus, 75015 Paris, France
| | - Isabel Valsecchi
- Institut Pasteur, Unité des Aspergillus, 75015 Paris, France
- DYNAMYC 7380, Faculté de Santé, Université Paris-Est Créteil (UPEC), 94010 Créteil, France
| | - Rémy A. Le Meur
- Institut Pasteur, Université Paris Cité, Centre National de la Recherche Scientifique (CNRS) UMR3528, Biological NMR and HDX-MS Technological Platform, 75015 Paris, France
| | - Catherine Simenel
- Institut Pasteur, Université Paris Cité, Centre National de la Recherche Scientifique (CNRS) UMR3528, Biological NMR and HDX-MS Technological Platform, 75015 Paris, France
| | - J. Iñaki Guijarro
- Institut Pasteur, Université Paris Cité, Centre National de la Recherche Scientifique (CNRS) UMR3528, Biological NMR and HDX-MS Technological Platform, 75015 Paris, France
| | - Catherine Comte
- Institut Pasteur, Unité des Aspergillus, 75015 Paris, France
| | | | - Isabelle Mouyna
- Institut Pasteur, Unité des Aspergillus, 75015 Paris, France
- Institut Pasteur, Université Paris Cité, Unité de Biologie des ARN des Pathogènes Fongiques, 75015 Paris, France
| | - Bernard Henrissat
- Architecture et Fonction des Macromolécules Biologiques, CNRS, Aix-Marseille Université Marseille, 163 Avenue de Luminy, CEDEX 09, 13288 Marseille, France
| | - Vishukumar Aimanianda
- Institut Pasteur, Université Paris Cité, CNRS UMR2000, Unité de Mycologie Moléculaire, 75015 Paris, France
| | - Jean-Paul Latgé
- Institut Pasteur, Unité des Aspergillus, 75015 Paris, France
| | - Thierry Fontaine
- Institut Pasteur, Unité des Aspergillus, 75015 Paris, France
- Institut Pasteur, Université Paris Cité, INRAE, USC2019, Unité Biologie et Pathogénicité Fongiques, 75015 Paris, France
- Correspondence:
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12
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Seegers CII, Lee DJ, Zarnovican P, Kirsch SH, Müller R, Haselhorst T, Routier FH. Identification of Compounds Preventing A. fumigatus Biofilm Formation by Inhibition of the Galactosaminogalactan Deacetylase Agd3. Int J Mol Sci 2023; 24:ijms24031851. [PMID: 36768176 PMCID: PMC9915216 DOI: 10.3390/ijms24031851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 01/12/2023] [Accepted: 01/13/2023] [Indexed: 01/19/2023] Open
Abstract
The opportunistic fungus Aspergillus fumigatus causes a set of diseases ranging from allergy to lethal invasive mycosis. Within the human airways, A. fumigatus is embedded in a biofilm that forms not only a barrier against the host immune defense system, but also creates a physical barrier protecting the fungi from chemicals such as antifungal drugs. Novel therapeutic strategies aim at combining drugs that inhibit biofilm synthesis or disrupt existing biofilm with classical antimicrobials. One of the major constituents of A. fumigatus biofilm is the polysaccharide galactosaminogalactan (GAG) composed of α1,4-linked N-acetylgalactosamine, galactosamine, and galactose residues. GAG is synthesized on the cytosolic face of the plasma membrane and is extruded in the extracellular space, where it is partially deacetylated. The deacetylase Agd3 that mediates this last step is essential for the biofilm formation and full virulence of the fungus. In this work, a previously described enzyme-linked lectin assay, based on the adhesion of deacetylated GAG to negatively charged plates and quantification with biotinylated soybean agglutinin was adapted to screen microbial natural compounds, as well as compounds identified in in silico screening of drug libraries. Actinomycin X2, actinomycin D, rifaximin, and imatinib were shown to inhibit Agd3 activity in vitro. At a concentration of 100 µM, actinomycin D and imatinib showed a clear reduction in the biofilm biomass without affecting the fungal growth. Finally, imatinib reduced the virulence of A. fumigatus in a Galleria mellonella infection model in an Agd3-dependent manner.
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Affiliation(s)
- Carla I. I. Seegers
- Institute for Clinical Biochemistry, OE4340, Hannover Medical School, Carl-Neuberg-Strasse 1, 30625 Hannover, Germany
| | - Danielle J. Lee
- Institute for Glycomics, Griffith University, Gold Coast Campus, Queensland 4222, Australia
| | - Patricia Zarnovican
- Institute for Clinical Biochemistry, OE4340, Hannover Medical School, Carl-Neuberg-Strasse 1, 30625 Hannover, Germany
| | - Susanne H. Kirsch
- Department of Microbial Natural Products, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Center for Infection Research, Saarland University Campus, 66123 Saarbrücken, Germany
- German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 38124 Braunschweig, Germany
| | - Rolf Müller
- Department of Microbial Natural Products, Helmholtz Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Center for Infection Research, Saarland University Campus, 66123 Saarbrücken, Germany
- German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 38124 Braunschweig, Germany
- Department of Pharmacy, Saarland University, 66123 Saarbrücken, Germany
| | - Thomas Haselhorst
- Institute for Glycomics, Griffith University, Gold Coast Campus, Queensland 4222, Australia
| | - Françoise H. Routier
- Institute for Clinical Biochemistry, OE4340, Hannover Medical School, Carl-Neuberg-Strasse 1, 30625 Hannover, Germany
- Correspondence:
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13
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Lecointe K, Coulon P, Krzewinski F, Charlet R, Bortolus C, Sendid B, Cornu M. Parietal composition of Lichtheimia corymbifera: Differences between spore and germ tube stages and host-pathogen interactions. Med Mycol 2022; 61:6960681. [PMID: 36565722 DOI: 10.1093/mmy/myac100] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2022] [Revised: 12/21/2022] [Accepted: 12/23/2022] [Indexed: 12/26/2022] Open
Abstract
The molecular composition and structural organization of the cell wall of filamentous fungi underlie the ability of the host to identify them as pathogens. Although the organization of the fungal cell wall, composed of 90% polysaccharides, is similar from one fungus to another, small variations condition their ability to trigger pattern recognition receptors. Because the incidence of mucormycosis, an emerging life-threatening infection caused by the species of the order Mucorales is increasing worldwide, the precise composition of the cell wall of two strains of Lichtheimia corymbifera was investigated in the early growth stages of germination (spores and germ-tubes) using trimethylsilylation and confocal microscopy. This study also characterizes the response of THP-1 cells to Mucorales. The study identified the presence of uncommon monosaccharides (fucose, galactose, and glucuronic acid) whose respective proportions vary according to the germination stage, revealing early parietal reorganization. Immunofluorescence studies confirmed the exposure of β-glucan on the surface of swollen spores and germ-tubes. Both spores and germ-tubes of L. corymbifera promoted an early and strong pro-inflammatory response, through TLR-2. Our results show the singularity of the cell wall of the order Mucorales, opening perspectives for the development of specific diagnostic biomarkers.
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Affiliation(s)
- Karine Lecointe
- CNRS, UMR 8576 - UGSF - Unité de Glycobiologie Structurale et Fonctionnelle, Univ. Lille, F-59000 Lille, France.,Inserm U1285 ; Univ. Lille, F-59000 Lille, France.,CHU Lille, Laboratoire de Parasitologie-Mycologie, F-59000 Lille, France
| | - Pauline Coulon
- CNRS, UMR 8576 - UGSF - Unité de Glycobiologie Structurale et Fonctionnelle, Univ. Lille, F-59000 Lille, France.,Inserm U1285 ; Univ. Lille, F-59000 Lille, France.,CHU Lille, Laboratoire de Parasitologie-Mycologie, F-59000 Lille, France
| | - Frédéric Krzewinski
- CNRS, UMR 8576 - UGSF - Unité de Glycobiologie Structurale et Fonctionnelle, Univ. Lille, F-59000 Lille, France
| | - Rogatien Charlet
- CNRS, UMR 8576 - UGSF - Unité de Glycobiologie Structurale et Fonctionnelle, Univ. Lille, F-59000 Lille, France.,Inserm U1285 ; Univ. Lille, F-59000 Lille, France
| | - Clovis Bortolus
- CNRS, UMR 8576 - UGSF - Unité de Glycobiologie Structurale et Fonctionnelle, Univ. Lille, F-59000 Lille, France.,Inserm U1285 ; Univ. Lille, F-59000 Lille, France
| | - Boualem Sendid
- CNRS, UMR 8576 - UGSF - Unité de Glycobiologie Structurale et Fonctionnelle, Univ. Lille, F-59000 Lille, France.,Inserm U1285 ; Univ. Lille, F-59000 Lille, France.,CHU Lille, Laboratoire de Parasitologie-Mycologie, F-59000 Lille, France
| | - Marjorie Cornu
- CNRS, UMR 8576 - UGSF - Unité de Glycobiologie Structurale et Fonctionnelle, Univ. Lille, F-59000 Lille, France.,Inserm U1285 ; Univ. Lille, F-59000 Lille, France.,CHU Lille, Laboratoire de Parasitologie-Mycologie, F-59000 Lille, France
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14
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Identification of an α-(1 →6)-Mannosyltransferase Contributing To Biosynthesis of the Fungal-Type Galactomannan α-Core-Mannan Structure in Aspergillus fumigatus. mSphere 2022; 7:e0048422. [PMID: 36445154 PMCID: PMC9769593 DOI: 10.1128/msphere.00484-22] [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] [Indexed: 12/02/2022] Open
Abstract
Fungal-type galactomannan, a cell wall component of Aspergillus fumigatus, is composed of α-(1→2)-/α-(1→6)-linked mannan and β-(1→5)-/β-(1→6)-linked galactofuran side chains. Recently, CmsA and CmsB were identified as the α-(1→2)-mannosyltransferases involved in the biosynthesis of the α-core-mannan. However, the α-(1→6)-mannosyltransferase involved in the biosynthesis of the α-core-mannan has not been identified yet. In this study, we analyzed 9 putative α-(1→6)-mannosyltransferase gene disruption strains of A. fumigatus. The ΔanpA strain resulted in decreased mycelial elongation and reduced conidia formation. Proton nuclear magnetic resonance analysis revealed that the ΔanpA strain failed to produce the α-core-mannan of fungal-type galactomannan. We also found that recombinant AnpA exhibited much stronger α-(1→6)-mannosyltransferase activity toward α-(1→2)-mannobiose than α-(1→6)-mannobiose in vitro. Molecular simulations corroborated the fact that AnpA has a structure that can recognize the donor and acceptor substrates suitable for α-(1→6)-mannoside bond formation and that its catalytic activity would be specific for the elongation of the α-core-mannan structure in vivo. The identified AnpA is similar to Anp1p, which is involved in the elongation of the N-glycan outer chain in budding yeast, but the building sugar chain structure is different. The difference was attributed to the difference in substrate recognition of AnpA, which was clarified by simulations based on protein conformation. Thus, even proteins that seem to be functionally identical due to amino acid sequence similarity may be glycosyltransferase enzymes that make different glycans upon detailed analysis. This study describes an example of such a case. IMPORTANCE Fungal-type galactomannan is a polysaccharide incorporated into the cell wall of filamentous fungi belonging to the subphylum Pezizomycotina. Biosynthetic enzymes of fungal-type galactomannan are potential targets for antifungal drugs and agrochemicals. In this study, we identified an α-(1→6)-mannosyltransferase responsible for the biosynthesis of the α-core-mannan of fungal-type galactomannan, which has not been known for a long time. The findings of this study shed light on processes that shape this cellular structure while identifying a key enzyme essential for the biosynthesis of fungal-type galactomannan.
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15
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de Oliveira Silva A, Aliyeva-Schnorr L, Wirsel SGR, Deising HB. Fungal Pathogenesis-Related Cell Wall Biogenesis, with Emphasis on the Maize Anthracnose Fungus Colletotrichum graminicola. PLANTS (BASEL, SWITZERLAND) 2022; 11:plants11070849. [PMID: 35406829 PMCID: PMC9003368 DOI: 10.3390/plants11070849] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2022] [Revised: 03/14/2022] [Accepted: 03/17/2022] [Indexed: 05/25/2023]
Abstract
The genus Colletotrichum harbors many plant pathogenic species, several of which cause significant yield losses in the field and post harvest. Typically, in order to infect their host plants, spores germinate, differentiate a pressurized infection cell, and display a hemibiotrophic lifestyle after plant invasion. Several factors required for virulence or pathogenicity have been identified in different Colletotrichum species, and adaptation of cell wall biogenesis to distinct stages of pathogenesis has been identified as a major pre-requisite for the establishment of a compatible parasitic fungus-plant interaction. Here, we highlight aspects of fungal cell wall biogenesis during plant infection, with emphasis on the maize leaf anthracnose and stalk rot fungus, Colletotrichum graminicola.
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Two Monoclonal Antibodies That Specifically Recognize Aspergillus Cell Wall Antigens and Can Detect Circulating Antigens in Infected Mice. Int J Mol Sci 2021; 23:ijms23010252. [PMID: 35008678 PMCID: PMC8745570 DOI: 10.3390/ijms23010252] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Revised: 12/16/2021] [Accepted: 12/19/2021] [Indexed: 01/25/2023] Open
Abstract
Invasive aspergillosis (IA) is a life-threatening disease mainly caused by Aspergillus fumigatus and Aspergillus flavus. Early diagnosis of this condition is crucial for patient treatment and survival. As current diagnostic techniques for IA lack sufficient accuracy, we have raised two monoclonal antibodies (1D2 and 4E4) against A. fumigatus cell wall fragments that may provide a platform for a new diagnostic approach. The immunoreactivity of these antibodies was tested by immunofluorescence and ELISA against various Aspergillus and Candida species in vitro and by immunohistochemistry in A. fumigatus infected mouse tissues. Both monoclonal antibodies (mAbs) showed intensive fluorescence with the hyphae wall of A. fumigatus and A. flavus, but there was no staining with other Aspergillus species or Candida species. Both mAbs also showed strong immunoreactivity to the cell wall of A. fumigatus hyphae in the infected liver, spleen and kidney of mice with IA. The antigens identified by 1D2 and 4E4 might be glycoproteins and the epitopes are most likely a protein or peptide rather than a carbohydrate. An antibody-based antigen capture ELISA detected the extracellular antigens released by A. fumigatus, A. flavus, A. niger and A. terreus, but not in Candida species. The antigen could be detected in the plasma of mice after 48 h of infection by double-sandwich ELISA. In conclusion, both 1D2 and 4E4 mAbs are potentially promising diagnostic tools to investigate invasive aspergillosis.
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17
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Chakraborty A, Fernando LD, Fang W, Dickwella Widanage MC, Wei P, Jin C, Fontaine T, Latgé JP, Wang T. A molecular vision of fungal cell wall organization by functional genomics and solid-state NMR. Nat Commun 2021; 12:6346. [PMID: 34732740 PMCID: PMC8566572 DOI: 10.1038/s41467-021-26749-z] [Citation(s) in RCA: 46] [Impact Index Per Article: 15.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 10/21/2021] [Indexed: 12/16/2022] Open
Abstract
Vast efforts have been devoted to the development of antifungal drugs targeting the cell wall, but the supramolecular architecture of this carbohydrate-rich composite remains insufficiently understood. Here we compare the cell wall structure of a fungal pathogen Aspergillus fumigatus and four mutants depleted of major structural polysaccharides. High-resolution solid-state NMR spectroscopy of intact cells reveals a rigid core formed by chitin, β-1,3-glucan, and α-1,3-glucan, with galactosaminogalactan and galactomannan present in the mobile phase. Gene deletion reshuffles the composition and spatial organization of polysaccharides, with significant changes in their dynamics and water accessibility. The distribution of α-1,3-glucan in chemically isolated and dynamically distinct domains supports its functional diversity. Identification of valines in the alkali-insoluble carbohydrate core suggests a putative function in stabilizing macromolecular complexes. We propose a revised model of cell wall architecture which will improve our understanding of the structural response of fungal pathogens to stresses. The fungal cell wall is a complex structure composed mainly of glucans, chitin and glycoproteins. Here, the authors use solid-state NMR spectroscopy to assess the cell wall architecture of Aspergillus fumigatus, comparing wild-type cells and mutants lacking major structural polysaccharides, with insights into the distinct functions of these components.
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Affiliation(s)
- Arnab Chakraborty
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, USA
| | | | - Wenxia Fang
- State Key Laboratory of Non-food Biomass and Enzyme Technology, Guangxi Academy of Sciences, Nanning, China
| | | | - Pingzhen Wei
- State Key Laboratory of Non-food Biomass and Enzyme Technology, Guangxi Academy of Sciences, Nanning, China
| | - Cheng Jin
- State Key Laboratory of Non-food Biomass and Enzyme Technology, Guangxi Academy of Sciences, Nanning, China.,State Key Laboratory of Mycology, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Thierry Fontaine
- Unité de Biologie et pathogénicité fongiques, INRAE, USC2019, Institut Pasteur, Paris, France
| | - Jean-Paul Latgé
- Institute of Molecular biology and Biotechnology (IMBBFORTH), University of Crete, Heraklion, Greece.
| | - Tuo Wang
- Department of Chemistry, Louisiana State University, Baton Rouge, LA, USA.
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Turning Inside Out: Filamentous Fungal Secretion and Its Applications in Biotechnology, Agriculture, and the Clinic. J Fungi (Basel) 2021; 7:jof7070535. [PMID: 34356914 PMCID: PMC8307877 DOI: 10.3390/jof7070535] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Revised: 06/14/2021] [Accepted: 06/25/2021] [Indexed: 12/15/2022] Open
Abstract
Filamentous fungi are found in virtually every marine and terrestrial habitat. Vital to this success is their ability to secrete a diverse range of molecules, including hydrolytic enzymes, organic acids, and small molecular weight natural products. Industrial biotechnologists have successfully harnessed and re-engineered the secretory capacity of dozens of filamentous fungal species to make a diverse portfolio of useful molecules. The study of fungal secretion outside fermenters, e.g., during host infection or in mixed microbial communities, has also led to the development of novel and emerging technological breakthroughs, ranging from ultra-sensitive biosensors of fungal disease to the efficient bioremediation of polluted environments. In this review, we consider filamentous fungal secretion across multiple disciplinary boundaries (e.g., white, green, and red biotechnology) and product classes (protein, organic acid, and secondary metabolite). We summarize the mechanistic understanding for how various molecules are secreted and present numerous applications for extracellular products. Additionally, we discuss how the control of secretory pathways and the polar growth of filamentous hyphae can be utilized in diverse settings, including industrial biotechnology, agriculture, and the clinic.
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Wang W, Fu R, Dong T, Cao Q, Ye H, Zhang C, Dong Z, Feng D, Zuo J. Guar gum-derived galactomannan induces inflammatory responses and increased energy expenditure in the intestine. Food Funct 2021; 12:7480-7489. [PMID: 34212169 DOI: 10.1039/d1fo01143j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Guar gum-derived galactomannan (GGGM) has been widely used in the food industry for a long time and its adverse impacts have been scarcely reported. Galactomannan is considered to have a structure similar to the surface components of certain pathogens, and the present study was thus conducted to investigate if oral administration of GGGM could cause physiological effects that were hypothesized to be related to intestinal inflammatory responses. The results showed that oral administration of GGGM resulted in compromises on growth performance, an increase of the relative weight of spleen and epididymal fat, and an elevation of the α1-acid glycoprotein content in both serum and livers of mice. With regard to energy metabolism-related indices, the activities of intestinal lactic dehydrogenase and succinic dehydrogenase were all increased by the GGGM treatment in both in vivo and in vitro experiments, the latter of which also showed an elevation in the consumption of reducing sugar by intestinal epithelial cells along with a reduced viability of these cells in response to the GGGM treatment. Notably, the GGGM treatment triggered intestinal inflammatory responses that were evidenced by the increased expression of intestinal inflammatory cytokines such as TNF-α and IL-6 both in vivo and in vitro, which were at least partially responsible for the increased energy expenditure in the intestine and the retardation of growth. The results of this study could expand our knowledge of GGGM administration and provide integrated insights into the consumption of GGGM-containing foods.
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Affiliation(s)
- Weiwei Wang
- College of Animal Science, South China Agricultural University, Guangzhou 510642, China.
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20
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Dysregulation of Key Proteinases in Aspergillus fumigatus Induced by Blood Platelets. Rep Biochem Mol Biol 2021; 10:95-104. [PMID: 34277873 DOI: 10.52547/rbmb.10.1.95] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Accepted: 12/13/2020] [Indexed: 11/18/2022]
Abstract
Background Aspergillus fumigatus is the most common species causing invasive aspergillosis (IA), a life-threatening infection with more than 80% mortality. Interactions between A. fumigatus and human blood platelets lead to intravascular thrombosis and localized infarcts. To better understand A. fumigatus pathogenesis, we aimed to analyze the genetic basis of interactions between the pathogen and blood platelets. Methods A bioinformatic pipeline on microarray gene expression dataset, including analysis of differentially expressed genes (DEGs) using Limma R package and their molecular function, as well as biological pathways identification, was conducted to find the effective genes involved in IA. In the wet phase, the gene expression patterns following fungal exposure to blood platelets at 15, 30, 60, and 180 min were evaluated by quantitative reverse transcriptase-PCR analysis. Results Three genes encoding aspartic endopeptidases including (Pep1), (Asp f 13), and (β-glucanase) were the standing candidates. The invasion-promoting fungal proteinase-encoding genes were down-regulated after 30 min of hyphal incubation with blood platelets, and then up-regulated at 60 and 180 min, although only Pep1 was greater than the control at the 60and 180 min time points. Also, the same genes were downregulated in more the clinical isolates relative to the standard strain CBS 144.89. Conclusion Our findings delineate the possible induction of fungal-encoded proteinases by blood platelets. This provides a new research line into A. fumigatus' molecular pathogenesis. Such insight into IA pathogenesis might also guide researchers toward novel platelet-based therapies that involve molecular interventions, especially in IA patients.
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