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Medina-Castellanos E, Salgado-Bautista DA, Martínez-Andrade JM, Cadena-Nava RD, Riquelme M. Nanosized extracellular vesicles released by Neurospora crassa hyphae. Fungal Genet Biol 2023; 165:103778. [PMID: 36690295 DOI: 10.1016/j.fgb.2023.103778] [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: 11/01/2022] [Revised: 01/13/2023] [Accepted: 01/17/2023] [Indexed: 01/22/2023]
Abstract
Extracellular vesicles (EVs) are nanosized structures containing proteins, lipids, and nucleic acids, released by living cells to the surrounding medium. EVs participate in diverse processes, such as intercellular communication, virulence, and disease. In pathogenic fungi, EVs carry enzymes that allow them to invade the host or undergo environmental adaptation successfully. In Neurospora crassa, a non-pathogenic filamentous fungus widely used as a model organism, the vesicle-dependent secretory mechanisms that lead to polarized growth are well studied. In contrast, biosynthesis of EVs in this fungus has been practically unexplored. In the present work, we analyzed N. crassa culture's supernatant for the presence of EVs by dynamic light scattering (DLS), transmission electron microscopy (TEM) and proteomic analysis. We identified spherical membranous structures, with a predominant subpopulation averaging a hydrodynamic diameter (dh) of 68 nm and a particle diameter (dp) of 38 nm. EV samples stained with osmium tetroxide vapors were better resolved than those stained with uranyl acetate. Mass spectrometry analysis identified 252 proteins, including enzymes involved in carbohydrate metabolic processes, oxidative stress response, cell wall organization/remodeling, and circadian clock-regulated proteins. Some of these proteins have been previously reported in exosomes from human cells or in EVs of other fungi. In view of the results, it is suggested a putative role for EVs in cell wall biosynthesis and vegetative development in N. crassa.
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Affiliation(s)
- Elizabeth Medina-Castellanos
- Department of Microbiology, Centro de Investigación Científica y Educación Superior de Ensenada (CICESE), Ensenada, Mexico
| | - Daniel A Salgado-Bautista
- Department of Microbiology, Centro de Investigación Científica y Educación Superior de Ensenada (CICESE), Ensenada, Mexico
| | - Juan M Martínez-Andrade
- Department of Microbiology, Centro de Investigación Científica y Educación Superior de Ensenada (CICESE), Ensenada, Mexico
| | - Ruben Dario Cadena-Nava
- Department of Bionanotechnology, Centro de Nanociencias y Nanotecnología, Universidad Nacional Autónoma de México, Ensenada, Mexico
| | - Meritxell Riquelme
- Department of Microbiology, Centro de Investigación Científica y Educación Superior de Ensenada (CICESE), Ensenada, Mexico.
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Samalova M, Flamant P, Beau R, Bromley M, Moya-Nilges M, Fontaine T, Latgé JP, Mouyna I. The New GPI-Anchored Protein, SwgA, Is Involved in Nitrogen Metabolism in the Pathogenic Filamentous Fungus Aspergillus fumigatus. J Fungi (Basel) 2023; 9:256. [PMID: 36836370 PMCID: PMC9960506 DOI: 10.3390/jof9020256] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 02/09/2023] [Accepted: 02/10/2023] [Indexed: 02/17/2023] Open
Abstract
GPI-anchored proteins display very diverse biological (biochemical and immunological) functions. An in silico analysis has revealed that the genome of Aspergillus fumigatus contains 86 genes coding for putative GPI-anchored proteins (GPI-APs). Past research has demonstrated the involvement of GPI-APs in cell wall remodeling, virulence, and adhesion. We analyzed a new GPI-anchored protein called SwgA. We showed that this protein is mainly present in the Clavati of Aspergillus and is absent from yeasts and other molds. The protein, localized in the membrane of A. fumigatus, is involved in germination, growth, and morphogenesis, and is associated with nitrogen metabolism and thermosensitivity. swgA is controlled by the nitrogen regulator AreA. This current study indicates that GPI-APs have more general functions in fungal metabolism than cell wall biosynthesis.
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Affiliation(s)
- Marketa Samalova
- Unité des Aspergillus, Département de Mycologie Institut Pasteur, 25-28 rue du Docteur Roux, CEDEX 15, 75724 Paris, France
| | - Patricia Flamant
- Unité des Aspergillus, Département de Mycologie Institut Pasteur, 25-28 rue du Docteur Roux, CEDEX 15, 75724 Paris, France
| | - Rémi Beau
- Unité des Aspergillus, Département de Mycologie Institut Pasteur, 25-28 rue du Docteur Roux, CEDEX 15, 75724 Paris, France
| | - Mike Bromley
- Manchester Fungal Infection Group, Division of Infection, Immunity and Respiratory Medicine, Faculty of Biology, Medicine and Health, University of Manchester, CTF Building, Grafton Street, Manchester M13 9NT, UK
| | - Maryse Moya-Nilges
- Unité Technologie et Service Bioimagerie Ultrastructurale (UTechS UBI), Institut Pasteur, 28 rue du Docteur Roux, 75015 Paris, France
| | - Thierry Fontaine
- Unité des Aspergillus, Département de Mycologie Institut Pasteur, 25-28 rue du Docteur Roux, CEDEX 15, 75724 Paris, France
| | - Jean-Paul Latgé
- Unité des Aspergillus, Département de Mycologie Institut Pasteur, 25-28 rue du Docteur Roux, CEDEX 15, 75724 Paris, France
| | - Isabelle Mouyna
- Unité des Aspergillus, Département de Mycologie Institut Pasteur, 25-28 rue du Docteur Roux, CEDEX 15, 75724 Paris, France
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Verticillium dahliae CFEM proteins manipulate host immunity and differentially contribute to virulence. BMC Biol 2022; 20:55. [PMID: 35197059 PMCID: PMC8867779 DOI: 10.1186/s12915-022-01254-x] [Citation(s) in RCA: 18] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Accepted: 02/15/2022] [Indexed: 02/06/2023] Open
Abstract
Background Verticillium dahliae is a fungal pathogen that causes a vascular wilt on many economically important crops. Common fungal extracellular membrane (CFEM) domain proteins including secreted types have been implicated in virulence, but their roles in this pathogen are still unknown. Results Nine secreted small cysteine-rich proteins (VdSCPs) with CFEM domains were identified by bioinformatic analyses and their differential suppression of host immune responses were evaluated. Two of these proteins, VdSCP76 and VdSCP77, localized to the plant plasma membrane owing to their signal peptides and mediated broad-spectrum suppression of all immune responses induced by typical effectors. Deletion of either VdSCP76 or VdSCP77 significantly reduced the virulence of V. dahliae on cotton. Furthermore, VdSCP76 and VdSCP77 suppressed host immunity through the potential iron binding site conserved in CFEM family members, characterized by an aspartic acid residue in seven VdSCPs (Asp-type) in contrast with an asparagine residue (Asn-type) in VdSCP76 and VdSCP77. V. dahliae isolates carrying the Asn-type CFEM members were more virulent on cotton than those carrying the Asp-type. Conclusions In the iron-insufficient xylem, V. dahliae is likely to employ the Asp-type CFEM members to chelate iron, and Asn-type CFEM members to suppress immunity, for successful colonization and propagation in host plants. Supplementary Information The online version contains supplementary material available at 10.1186/s12915-022-01254-x.
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Saucedo-Campa DO, Martínez-Rocha AL, Ríos-Castro E, Alba-Fierro CA, Escobedo-Bretado MA, Cuéllar-Cruz M, Ruiz-Baca E. Proteomic Analysis of Sporothrix schenckii Exposed to Oxidative Stress Induced by Hydrogen Peroxide. Pathogens 2022; 11:pathogens11020230. [PMID: 35215174 PMCID: PMC8880468 DOI: 10.3390/pathogens11020230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 02/05/2022] [Accepted: 02/07/2022] [Indexed: 11/17/2022] Open
Abstract
Sporothrix schenckii modulates the expression of its cell wall proteins (CWPs) in response to reactive oxygen species (ROS) generated by the phagocytic cells of the human host, which allows it to evade and escape the immune system. In this study, we performed a comparative proteomic analysis of the CW of S. schenckii after exposure and nonexposure to H2O2. Several CWPs involved in CW remodeling and fungal pathogenesis that modulated their expression in response to this oxidizing agent were identified, as were a number of antioxidant enzymes and atypical CWPs, called moonlighting proteins, such as the Hsp70-5, lipase 1 (Lip1), enolase (Eno), and pyruvate kinase (Pk). Moreover, RT-qPCR assays demonstrated that the transcription of genes HSP70-5, LIP1, ENO, and PK is regulated in response to the oxidant. The results indicated that S. schenckii differentially expressed CWPs to confer protection against ROS upon this fungus. Furthermore, among these proteins, antioxidant enzymes and interestingly, moonlighting-like CWPs play a role in protecting the fungus from oxidative stress (OS), allowing it to infect human host cells.
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Affiliation(s)
- Dulce O. Saucedo-Campa
- Facultad de Ciencias Químicas (Unidad Durango), Universidad Juárez del Estado de Durango, Av. Veterinaria S/N, Durango 34120, Mexico; (D.O.S.-C.); (A.L.M.-R.); (C.A.A.-F.); (M.A.E.-B.)
| | - Ana L. Martínez-Rocha
- Facultad de Ciencias Químicas (Unidad Durango), Universidad Juárez del Estado de Durango, Av. Veterinaria S/N, Durango 34120, Mexico; (D.O.S.-C.); (A.L.M.-R.); (C.A.A.-F.); (M.A.E.-B.)
| | - Emmanuel Ríos-Castro
- Centro de Investigación y de Estudios Avanzados del I.P.N., Unidad de Genómica, Proteómica y Metabolómica, LaNSE, Ciudad de Mexico 07360, Mexico;
| | - Carlos A. Alba-Fierro
- Facultad de Ciencias Químicas (Unidad Durango), Universidad Juárez del Estado de Durango, Av. Veterinaria S/N, Durango 34120, Mexico; (D.O.S.-C.); (A.L.M.-R.); (C.A.A.-F.); (M.A.E.-B.)
| | - Miguel A. Escobedo-Bretado
- Facultad de Ciencias Químicas (Unidad Durango), Universidad Juárez del Estado de Durango, Av. Veterinaria S/N, Durango 34120, Mexico; (D.O.S.-C.); (A.L.M.-R.); (C.A.A.-F.); (M.A.E.-B.)
| | - Mayra Cuéllar-Cruz
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Noria Alta S/N, Guanajuato 36050, Mexico;
| | - Estela Ruiz-Baca
- Facultad de Ciencias Químicas (Unidad Durango), Universidad Juárez del Estado de Durango, Av. Veterinaria S/N, Durango 34120, Mexico; (D.O.S.-C.); (A.L.M.-R.); (C.A.A.-F.); (M.A.E.-B.)
- Correspondence:
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Chen L, Wang H, Yang J, Yang X, Zhang M, Zhao Z, Fan Y, Wang C, Wang J. Bioinformatics and Transcriptome Analysis of CFEM Proteins in Fusarium graminearum. J Fungi (Basel) 2021; 7:jof7100871. [PMID: 34682292 PMCID: PMC8540330 DOI: 10.3390/jof7100871] [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: 09/26/2021] [Revised: 10/13/2021] [Accepted: 10/14/2021] [Indexed: 01/25/2023] Open
Abstract
Fusarium blight of wheat is usually caused by Fusarium graminearum, and the pathogenic fungi will secrete effectors into the host plant tissue to affect its normal physiological process, so as to make it pathogenic. The CFEM (Common in Fungal Extracellular Membrane) protein domain is unique to fungi, but it is not found in all fungi. The CFEM protein contained in F. graminearum may be closely related to pathogenicity. In this study, 23 FgCFEM proteins were identified from the F. graminearum genome. Then, features of these proteins, such as signal peptide, subcellular localization, and transmembrane domains, etc., were analyzed and candidate effectors were screened out. Sequence alignment results revealed that each FgCFEM protein contains one CFEM domain. The amino acids of the CFEM domain are highly conserved and contain eight spaced cysteines, with the exception that FgCFEM8, 9, and 15 lack two cysteines and three cysteines were missed in FgCFEM18 and FgCFEM22. A recently identified CFEM_DR motif was detected in 11 FgCFEMs, and importantly we identified two new conserved motifs containing about 29 and 18 amino acids (CFEM_WR and CFEM_KF), respectively, in some of FgCFEM proteins. Transcriptome analysis of the genes encoding CFEM proteins indicated that all the CFEM-containing genes were expressed during wheat infection, with seven and six genes significantly up- and down-regulated, respectively, compared with in planta and in vitro. Based on the above analysis, FgCFEM11 and FgCFEM23 were predicted to be F. graminearum effectors. This study provides the basis for future functional analyses of CFEM proteins in F. graminearum.
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Affiliation(s)
- Lingqiao Chen
- College of Food Science & Technology, Shanghai Ocean University, Shanghai 201306, China; (L.C.); (H.W.); (M.Z.)
- Shanghai Key Laboratory of Protected Horticultural Technology, Laboratory of Quality and Safety Risk Assessment for Agro-Products (Shanghai), Institute for Agro-Food Standards and Testing Technology, Ministry of Agriculture, Shanghai Academy of Agricultural Sciences, 1000 Jinqi Road, Shanghai 201403, China; (J.Y.); (X.Y.); (Z.Z.)
| | - Haoyu Wang
- College of Food Science & Technology, Shanghai Ocean University, Shanghai 201306, China; (L.C.); (H.W.); (M.Z.)
- Shanghai Key Laboratory of Protected Horticultural Technology, Laboratory of Quality and Safety Risk Assessment for Agro-Products (Shanghai), Institute for Agro-Food Standards and Testing Technology, Ministry of Agriculture, Shanghai Academy of Agricultural Sciences, 1000 Jinqi Road, Shanghai 201403, China; (J.Y.); (X.Y.); (Z.Z.)
| | - Junhua Yang
- Shanghai Key Laboratory of Protected Horticultural Technology, Laboratory of Quality and Safety Risk Assessment for Agro-Products (Shanghai), Institute for Agro-Food Standards and Testing Technology, Ministry of Agriculture, Shanghai Academy of Agricultural Sciences, 1000 Jinqi Road, Shanghai 201403, China; (J.Y.); (X.Y.); (Z.Z.)
| | - Xianli Yang
- Shanghai Key Laboratory of Protected Horticultural Technology, Laboratory of Quality and Safety Risk Assessment for Agro-Products (Shanghai), Institute for Agro-Food Standards and Testing Technology, Ministry of Agriculture, Shanghai Academy of Agricultural Sciences, 1000 Jinqi Road, Shanghai 201403, China; (J.Y.); (X.Y.); (Z.Z.)
| | - Mengyuan Zhang
- College of Food Science & Technology, Shanghai Ocean University, Shanghai 201306, China; (L.C.); (H.W.); (M.Z.)
- Shanghai Key Laboratory of Protected Horticultural Technology, Laboratory of Quality and Safety Risk Assessment for Agro-Products (Shanghai), Institute for Agro-Food Standards and Testing Technology, Ministry of Agriculture, Shanghai Academy of Agricultural Sciences, 1000 Jinqi Road, Shanghai 201403, China; (J.Y.); (X.Y.); (Z.Z.)
| | - Zhihui Zhao
- Shanghai Key Laboratory of Protected Horticultural Technology, Laboratory of Quality and Safety Risk Assessment for Agro-Products (Shanghai), Institute for Agro-Food Standards and Testing Technology, Ministry of Agriculture, Shanghai Academy of Agricultural Sciences, 1000 Jinqi Road, Shanghai 201403, China; (J.Y.); (X.Y.); (Z.Z.)
| | - Yingying Fan
- Institute of Quanlity Standards & Testing Technology for Agro-Products, Xinjiang Academy of Agricultural Sciences, Urumqi 830091, China; (Y.F.); (C.W.)
| | - Cheng Wang
- Institute of Quanlity Standards & Testing Technology for Agro-Products, Xinjiang Academy of Agricultural Sciences, Urumqi 830091, China; (Y.F.); (C.W.)
| | - Jianhua Wang
- College of Food Science & Technology, Shanghai Ocean University, Shanghai 201306, China; (L.C.); (H.W.); (M.Z.)
- Shanghai Key Laboratory of Protected Horticultural Technology, Laboratory of Quality and Safety Risk Assessment for Agro-Products (Shanghai), Institute for Agro-Food Standards and Testing Technology, Ministry of Agriculture, Shanghai Academy of Agricultural Sciences, 1000 Jinqi Road, Shanghai 201403, China; (J.Y.); (X.Y.); (Z.Z.)
- Correspondence: ; Tel.: +86-2167131637
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GPI Anchored Proteins in Aspergillus fumigatus and Cell Wall Morphogenesis. Curr Top Microbiol Immunol 2020; 425:167-186. [PMID: 32418035 DOI: 10.1007/82_2020_207] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Glycosylphosphatidylinositol (GPI) anchored proteins are a class of proteins attached to the extracellular leaflet of the plasma membrane via a post-translational modification, the glycolipid anchor. GPI anchored proteins are expressed in all eukaryotes, from fungi to plants and animals. They display very diverse functions ranging from enzymatic activity, signaling, cell adhesion, cell wall metabolism, and immune response. In this review, we investigated for the first time an exhaustive list of all the GPI anchored proteins present in the Aspergillus fumigatus genome. An A. fumigatus mutant library of all the genes that encode in silico identified GPI anchored proteins has been constructed and the phenotypic analysis of all these mutants has been characterized including their growth, conidial viability or morphology, adhesion and the ability to form biofilms. We showed the presence of different fungal categories of GPI anchored proteins in the A. fumigatus genome associated to their role in cell wall remodeling, adhesion, and biofilm formation.
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Arya GC, Srivastava DA, Pandaranayaka EPJ, Manasherova E, Prusky DB, Elad Y, Frenkel O, Dvir H, Harel A. Characterization of the Role of a Non-GPCR Membrane-Bound CFEM Protein in the Pathogenicity and Germination of Botrytis cinerea. Microorganisms 2020; 8:microorganisms8071043. [PMID: 32674341 PMCID: PMC7409268 DOI: 10.3390/microorganisms8071043] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Revised: 07/10/2020] [Accepted: 07/11/2020] [Indexed: 01/01/2023] Open
Abstract
The necrotrophic fungus Botrytis cinerea, is considered a major cause of postharvest losses in a wide range of crops. The common fungal extracellular membrane protein (CFEM), containing a conserved eight-cysteine pattern, was found exclusively in fungi. Previous studies in phytopathogenic fungi have demonstrated the role of membrane-bound and secreted CFEM-containing proteins in different aspects of fungal virulence. However, non-G protein-coupled receptor (non-GPCR) membrane CFEM proteins have not been studied yet in phytopathogenic fungi. In the present study, we have identified a non-GPCR membrane-bound CFEM-containing protein, Bcin07g03260, in the B. cinerea genome, and generated deletion mutants, ΔCFEM-Bcin07g03260, to study its potential role in physiology and virulence. Three independent ΔCFEM-Bcin07g03260 mutants showed significantly reduced progression of a necrotic lesion on tomato (Solanum lycopersicum) leaves. Further analysis of the mutants revealed significant reduction (approximately 20–30%) in conidial germination and consequent germ tube elongation compared with the WT. Our data complements a previous study of secreted ΔCFEM1 mutants of B. cinerea that showed reduced progression of necrotic lesions on leaves, without effect on germination. Considering various functions identified for CFEM proteins in fungal virulence, our work illustrates a potential new role for a non-GPCR membrane CFEM in pathogenic fungi to control virulence in the fungus B. cinerea.
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Affiliation(s)
- Gulab Chand Arya
- Department of Vegetable and Field Crops, Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion 7505101, Israel; (G.C.A.); (D.A.S.); (E.P.J.P.); (E.M.)
| | - Dhruv Aditya Srivastava
- Department of Vegetable and Field Crops, Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion 7505101, Israel; (G.C.A.); (D.A.S.); (E.P.J.P.); (E.M.)
| | - Eswari P. J. Pandaranayaka
- Department of Vegetable and Field Crops, Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion 7505101, Israel; (G.C.A.); (D.A.S.); (E.P.J.P.); (E.M.)
| | - Ekaterina Manasherova
- Department of Vegetable and Field Crops, Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion 7505101, Israel; (G.C.A.); (D.A.S.); (E.P.J.P.); (E.M.)
| | - Dov Bernard Prusky
- Department of Postharvest Science, Institute of Postharvest and Food Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion7505101, Israel;
| | - Yigal Elad
- Department of Plant Pathology and Weed Research, Institute of Plant Protection, Agricultural Research Organization, Volcani Center, Rishon LeZion 7505101, Israel; (Y.E.); (O.F.)
| | - Omer Frenkel
- Department of Plant Pathology and Weed Research, Institute of Plant Protection, Agricultural Research Organization, Volcani Center, Rishon LeZion 7505101, Israel; (Y.E.); (O.F.)
| | - Hay Dvir
- Department of Ruminant Science, Institute of Animal Science, Agricultural Research Organization, Volcani Center, Rishon LeZion 7505101, Israel;
| | - Arye Harel
- Department of Vegetable and Field Crops, Institute of Plant Sciences, Agricultural Research Organization, Volcani Center, Rishon LeZion 7505101, Israel; (G.C.A.); (D.A.S.); (E.P.J.P.); (E.M.)
- Correspondence: ; Tel.: +972-3-968-3644
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Heme-iron acquisition in fungi. Curr Opin Microbiol 2019; 52:77-83. [DOI: 10.1016/j.mib.2019.05.006] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 05/30/2019] [Accepted: 05/31/2019] [Indexed: 01/09/2023]
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9
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Shivarathri R, Tscherner M, Zwolanek F, Singh NK, Chauhan N, Kuchler K. The Fungal Histone Acetyl Transferase Gcn5 Controls Virulence of the Human Pathogen Candida albicans through Multiple Pathways. Sci Rep 2019; 9:9445. [PMID: 31263212 PMCID: PMC6603162 DOI: 10.1038/s41598-019-45817-5] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Accepted: 06/14/2019] [Indexed: 12/28/2022] Open
Abstract
Fungal virulence is regulated by a tight interplay of transcriptional control and chromatin remodelling. Despite compelling evidence that lysine acetylation modulates virulence of pathogenic fungi such as Candida albicans, the underlying mechanisms have remained largely unexplored. We report here that Gcn5, a paradigm lysyl-acetyl transferase (KAT) modifying both histone and non-histone targets, controls fungal morphogenesis - a key virulence factor of C. albicans. Our data show that genetic removal of GCN5 abrogates fungal virulence in mice, suggesting strongly diminished fungal fitness in vivo. This may at least in part arise from increased susceptibility to killing by macrophages, as well as by other phagocytes such as neutrophils or monocytes. Loss of GCN5 also causes hypersensitivity to the fungicidal drug caspofungin. Caspofungin hypersusceptibility requires the master regulator Efg1, working in concert with Gcn5. Moreover, Gcn5 regulates multiple independent pathways, including adhesion, cell wall-mediated MAP kinase signaling, hypersensitivity to host-derived oxidative stress, and regulation of the Fks1 glucan synthase, all of which play critical roles in virulence and antifungal susceptibility. Hence, Gcn5 regulates fungal virulence through multiple mechanisms, suggesting that specific inhibition of Gcn5 could offer new therapeutic strategies to combat invasive fungal infections.
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Affiliation(s)
- Raju Shivarathri
- Medical University of Vienna, Max Perutz Labs Vienna, Campus Vienna Biocenter, A-1030, Vienna, Austria
| | - Michael Tscherner
- Medical University of Vienna, Max Perutz Labs Vienna, Campus Vienna Biocenter, A-1030, Vienna, Austria
| | - Florian Zwolanek
- Medical University of Vienna, Max Perutz Labs Vienna, Campus Vienna Biocenter, A-1030, Vienna, Austria
| | | | - Neeraj Chauhan
- Public Health Research Institute, New Jersey Medical School, Rutgers The State University of New Jersey, Newark, NJ, 07103, USA.
- Department of Microbiology, Biochemistry and Molecular Genetics, New Jersey Medical School, Rutgers The State University of New Jersey, Newark, NJ, 07103, USA.
| | - Karl Kuchler
- Medical University of Vienna, Max Perutz Labs Vienna, Campus Vienna Biocenter, A-1030, Vienna, Austria.
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Ramírez-Valdespino CA, Casas-Flores S, Olmedo-Monfil V. Trichoderma as a Model to Study Effector-Like Molecules. Front Microbiol 2019; 10:1030. [PMID: 31156578 PMCID: PMC6529561 DOI: 10.3389/fmicb.2019.01030] [Citation(s) in RCA: 50] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 04/24/2019] [Indexed: 11/24/2022] Open
Abstract
Plants are capable of perceiving microorganisms by coordinating processes to establish different forms of plant–microbe relationships. Plant colonization is governed in fungal and bacterial systems by secreted effector molecules, suppressing plant defense responses and modulating plant physiology to promote either virulence or compatibility. Proteins, secondary metabolites, and small RNAs have been described as effector molecules that use different mechanisms to establish the interaction. Effector molecules have been studied in more detail due to their involvement in harmful interactions, leading to a negative impact on agriculture. Recently, research groups have started to study the effectors in symbiotic interactions. Interestingly, most symbiotic effectors are members of the same families present in phytopathogens. Nevertheless, the quantity and ratio of secreted effectors depends on the microorganism and the host, suggesting a complex mechanism of recognition between the plant and their associated microorganisms. Fungi belonging to Trichoderma genus interact with plants by inducing their defense system and promoting plant growth. Research suggests that some of these effects are associated with effector molecules that Trichoderma delivers during the association with the plant. In this review, we will focus on the main findings concerning the effector molecules reported in Trichoderma spp. and their role during the interaction with plants, mainly in the molecular dialogue that takes place between them.
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Affiliation(s)
- Claudia A Ramírez-Valdespino
- División de Ciencias Naturales y Exactas, Departamento de Biología, Universidad de Guanajuato, Guanajuato, Mexico.,Laboratorio de Biohidrometalurgia, Departamento de Medio Ambiente y Energía, Centro de Investigación en Materiales Avanzados, Chihuahua, Mexico
| | - Sergio Casas-Flores
- Laboratorio de Genómica Funcional y Comparativa, División de Biología Molecular, Instituto Potosino de Investigación Científica y Tecnológica, San Luis Potosí, Mexico
| | - Vianey Olmedo-Monfil
- División de Ciencias Naturales y Exactas, Departamento de Biología, Universidad de Guanajuato, Guanajuato, Mexico
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Ramírez-Valdespino CA, Casas-Flores S, Olmedo-Monfil V. Trichoderma as a Model to Study Effector-Like Molecules. Front Microbiol 2019. [PMID: 31156578 DOI: 10.3389/pmic.2019.01030] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/20/2023] Open
Abstract
Plants are capable of perceiving microorganisms by coordinating processes to establish different forms of plant-microbe relationships. Plant colonization is governed in fungal and bacterial systems by secreted effector molecules, suppressing plant defense responses and modulating plant physiology to promote either virulence or compatibility. Proteins, secondary metabolites, and small RNAs have been described as effector molecules that use different mechanisms to establish the interaction. Effector molecules have been studied in more detail due to their involvement in harmful interactions, leading to a negative impact on agriculture. Recently, research groups have started to study the effectors in symbiotic interactions. Interestingly, most symbiotic effectors are members of the same families present in phytopathogens. Nevertheless, the quantity and ratio of secreted effectors depends on the microorganism and the host, suggesting a complex mechanism of recognition between the plant and their associated microorganisms. Fungi belonging to Trichoderma genus interact with plants by inducing their defense system and promoting plant growth. Research suggests that some of these effects are associated with effector molecules that Trichoderma delivers during the association with the plant. In this review, we will focus on the main findings concerning the effector molecules reported in Trichoderma spp. and their role during the interaction with plants, mainly in the molecular dialogue that takes place between them.
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Affiliation(s)
- Claudia A Ramírez-Valdespino
- División de Ciencias Naturales y Exactas, Departamento de Biología, Universidad de Guanajuato, Guanajuato, Mexico
- Laboratorio de Biohidrometalurgia, Departamento de Medio Ambiente y Energía, Centro de Investigación en Materiales Avanzados, Chihuahua, Mexico
| | - Sergio Casas-Flores
- Laboratorio de Genómica Funcional y Comparativa, División de Biología Molecular, Instituto Potosino de Investigación Científica y Tecnológica, San Luis Potosí, Mexico
| | - Vianey Olmedo-Monfil
- División de Ciencias Naturales y Exactas, Departamento de Biología, Universidad de Guanajuato, Guanajuato, Mexico
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Valsecchi I, Dupres V, Stephen-Victor E, Guijarro JI, Gibbons J, Beau R, Bayry J, Coppee JY, Lafont F, Latgé JP, Beauvais A. Role of Hydrophobins in Aspergillus fumigatus. J Fungi (Basel) 2017; 4:jof4010002. [PMID: 29371496 PMCID: PMC5872305 DOI: 10.3390/jof4010002] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 12/20/2017] [Accepted: 12/22/2017] [Indexed: 01/21/2023] Open
Abstract
Resistance of Aspergillus fumigatus conidia to desiccation and their capacity to reach the alveoli are partly due to the presence of a hydrophobic layer composed of a protein from the hydrophobin family, called RodA, which covers the conidial surface. In A. fumigatus there are seven hydrophobins (RodA-RodG) belonging to class I and III. Most of them have never been studied. We constructed single and multiple hydrophobin-deletion mutants until the generation of a hydrophobin-free mutant. The phenotype, immunogenicity, and virulence of the mutants were studied. RODA is the most expressed hydrophobin in sporulating cultures, whereas RODB is upregulated in biofilm conditions and in vivo Only RodA, however, is responsible for rodlet formation, sporulation, conidial hydrophobicity, resistance to physical insult or anionic dyes, and immunological inertia of the conidia. None of the hydrophobin plays a role in biofilm formation or its hydrophobicity. RodA is the only needed hydrophobin in A. fumigatus, conditioning the structure, permeability, hydrophobicity, and immune-inertia of the cell wall surface in conidia. Moreover, the defect of rodlets on the conidial cell wall surface impacts on the drug sensitivity of the fungus.
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Affiliation(s)
- Isabel Valsecchi
- Aspergillus Unit, Institut Pasteur, 75015 Paris, France.
- Unité de RMN des Biomolécules, Institut Pasteur, 75015 Paris, France.
| | - Vincent Dupres
- Centre for Infection and Immunity, Institut Pasteur de Lille-CNRS UMR8204-INSERM U1019-CHRU Lille-Université Lille, 59655 Lille, France.
| | - Emmanuel Stephen-Victor
- Institut National de la Santé et de la Recherche Médicale, Unité 1138, 75006 Paris, France.
- Centre de Recherche des Cordeliers, Université Pierre et Marie Curie-Paris 6, Université Paris Descartes, 75006 Paris, France.
| | - J Iñaki Guijarro
- Unité de RMN des Biomolécules, Institut Pasteur, 75015 Paris, France.
| | - John Gibbons
- Biology Department, Clark University, Worcester, MA 01610, USA.
| | - Rémi Beau
- Aspergillus Unit, Institut Pasteur, 75015 Paris, France.
| | - Jagadeesh Bayry
- Institut National de la Santé et de la Recherche Médicale, Unité 1138, 75006 Paris, France.
- Centre de Recherche des Cordeliers, Université Pierre et Marie Curie-Paris 6, Université Paris Descartes, 75006 Paris, France.
| | - Jean-Yves Coppee
- Transcriptome et Epigénome, Institut Pasteur, 75015 Paris, France.
| | - Frank Lafont
- Centre for Infection and Immunity, Institut Pasteur de Lille-CNRS UMR8204-INSERM U1019-CHRU Lille-Université Lille, 59655 Lille, France.
| | | | - Anne Beauvais
- Aspergillus Unit, Institut Pasteur, 75015 Paris, France.
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Zhu W, Wei W, Wu Y, Zhou Y, Peng F, Zhang S, Chen P, Xu X. BcCFEM1, a CFEM Domain-Containing Protein with Putative GPI-Anchored Site, Is Involved in Pathogenicity, Conidial Production, and Stress Tolerance in Botrytis cinerea. Front Microbiol 2017; 8:1807. [PMID: 28979251 PMCID: PMC5611420 DOI: 10.3389/fmicb.2017.01807] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2017] [Accepted: 09/05/2017] [Indexed: 12/13/2022] Open
Abstract
We experimentally isolated and characterized a CFEM protein with putative GPI-anchored site BcCFEM1 in Botrytis cinerea. BcCFEM1 contains a CFEM (common in several fungal extracellular membrane proteins) domain with the characteristic eight cysteine residues at N terminus, and a predicted GPI modification site at C terminus. BcCFEM1 was significantly up-regulated during early stage of infection on bean leaves and induced chlorosis in Nicotiana benthamiana leaves using Agrobacterium infiltration method. Targeted deletion of BcCFEM1 in B. cinerea affected virulence, conidial production and stress tolerance, but not growth rate, conidial germination, colony morphology, and sclerotial formation. However, over expression of BcCFEM1 did not make any observable phenotype change. Therefore, our data suggested that BcCFEM1 contributes to virulence, conidial production, and stress tolerance. These findings further enhance our understanding on the sophisticated pathogenicity of B. cinerea beyond necrotrophic stage, highlighting the importance of CFEM protein to B. cinerea and other broad-host-range necrotrophic pathogens.
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Affiliation(s)
- Wenjun Zhu
- College of Biology and Pharmaceutical Engineering, Wuhan Polytechnic UniversityWuhan, China
| | - Wei Wei
- Institute for Interdisciplinary Research, Jianghan UniversityWuhan, China
| | - Yayun Wu
- College of Biology and Pharmaceutical Engineering, Wuhan Polytechnic UniversityWuhan, China
| | - Yang Zhou
- College of Biology and Pharmaceutical Engineering, Wuhan Polytechnic UniversityWuhan, China
| | - Fang Peng
- College of Biology and Pharmaceutical Engineering, Wuhan Polytechnic UniversityWuhan, China
| | - Shaopeng Zhang
- College of Biology and Pharmaceutical Engineering, Wuhan Polytechnic UniversityWuhan, China
| | - Ping Chen
- College of Biology and Pharmaceutical Engineering, Wuhan Polytechnic UniversityWuhan, China
| | - Xiaowen Xu
- State Key Laboratory of Agrobiotechnology and Ministry of Agriculture Key Laboratory of Plant Pathology, China Agricultural UniversityBeijing, China
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Kou Y, Tan YH, Ramanujam R, Naqvi NI. Structure-function analyses of the Pth11 receptor reveal an important role for CFEM motif and redox regulation in rice blast. THE NEW PHYTOLOGIST 2017; 214:330-342. [PMID: 27898176 DOI: 10.1111/nph.14347] [Citation(s) in RCA: 78] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 10/23/2016] [Indexed: 05/20/2023]
Abstract
The interaction of Magnaporthe oryzae, the rice blast fungus, and rice begins when M. oryzae establishes contact with the host plant surface. On perception of appropriate surface signals, M. oryzae forms appressoria and initiates host invasion. Pth11, an important G-protein-coupled receptor necessary for appressorium formation in M. oryzae, contains seven transmembrane regions and a CFEM (common in several fungal extracellular membrane proteins) domain with the characteristic eight cysteine residues. We focused on gaining further insight into the role of the CFEM domain in the putative surface sensing/response function of Pth11. Increased/constitutive expression of CFEM resulted in precocious, albeit defective, appressoria formation in wild-type M. oryzae. The Pth11C63A/C65A mutant, probably with disrupted disulfide bonds in the CFEM, showed delayed appressorium formation and reduced virulence. Furthermore, the accumulation of reactive oxygen species (ROS) was found to be altered in the pth11Δ strain. Strikingly, antioxidant treatment induced appressorium formation in pth11Δ. The Gα subunit MagB and the mitogen-activated protein (MAP) kinase Pmk1 were required for the formation of antioxidant-induced appressoria. We conclude that the CFEM domain of Pth11 is required for proper development of the appressoria, appressoria-like structures and pathogenicity. Highly regulated ROS homeostasis is important for Pth11-mediated appressorium formation in M. oryzae.
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Affiliation(s)
- Yanjun Kou
- Temasek Life Sciences Laboratory, and Department of Biological Sciences, 1 Research Link, National University of Singapore, 117604, Singapore
- State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou, 117596, China
| | - Yi Han Tan
- Department of Biochemistry, National University of Singapore, 8 Medical Drive, 117596, Singapore
| | - Ravikrishna Ramanujam
- Temasek Life Sciences Laboratory, and Department of Biological Sciences, 1 Research Link, National University of Singapore, 117604, Singapore
| | - Naweed I Naqvi
- Temasek Life Sciences Laboratory, and Department of Biological Sciences, 1 Research Link, National University of Singapore, 117604, Singapore
- School of Biological Sciences, Nanyang Technological University, 637551, Singapore
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15
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Martínez JP, Blanes R, Casanova M, Valentín E, Murgui A, Domínguez Á. Null mutants of Candida albicans for cell-wall-related genes form fragile biofilms that display an almost identical extracellular matrix proteome. FEMS Yeast Res 2016; 16:fow075. [PMID: 27609602 DOI: 10.1093/femsyr/fow075] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/31/2016] [Indexed: 12/20/2022] Open
Abstract
By two-dimensional gel electrophoresis (2-DE) and mass spectrometry, we have characterized the polypeptide species present in extracts obtained by 60% ethanol treatment of whole mature (48 h) biofilms formed by a reference strain (CAI4-URA3) and four Candida albicans null mutants for cell-wall-related genes (ALG5, CSA1, MNN9 and PGA10) Null mutants form fragile biofilms that appeared partially split and weakly attached to the substratum contrary to those produced by the reference strain. An almost identical, electrophoretic profile consisting of about 276 spots was visualized in all extracts examined. Proteomic analysis led to the identification of 131 polypeptides, corresponding to 86 different protein species, being the rest isoforms-83 displayed negative hydropathic indexes and 82 lack signal peptide. The majority of proteins appeared at pI between 4 and 6, and molecular mass between 10 and 94 kDa. The proteins identified belonged to the following Gene Ontology categories: 21.9% unknown molecular function, 16.2% oxidoreductase activity, 13.3% hydrolase activity and 41.8% distributed between other different GO categories. Strong defects in biofilm formation appreciated in the cell-wall mutant strains could be attributed to defects in aggregation due to abnormal cell wall formation rather than to differences in the biofilm extracellular matrix composition.
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Affiliation(s)
- José P Martínez
- Department of Microbiology and Ecology, School of Pharmacy, University of Valencia, 46100 Burjasot, Valencia, Spain
| | - Rosario Blanes
- Department of Microbiology and Ecology, School of Pharmacy, University of Valencia, 46100 Burjasot, Valencia, Spain
| | - Manuel Casanova
- Department of Microbiology and Ecology, School of Pharmacy, University of Valencia, 46100 Burjasot, Valencia, Spain
| | - Eulogio Valentín
- Department of Microbiology and Ecology, School of Pharmacy, University of Valencia, 46100 Burjasot, Valencia, Spain
| | - Amelia Murgui
- Department of Biochemistry and Molecular Biology, School of Pharmacy, University of Valencia, 46100 Burjasot, Valencia, Spain
| | - Ángel Domínguez
- Department of Microbiology and Genetics, University of Salamanca, 37007 Salamanca, Spain
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Abstract
In vivo, Aspergillus fumigatus grows as a typical biofilm with hyphae covered by an extracellular matrix (ECM) composed of polysaccharides, galactomannan, and galactosaminogalactan. α1,3 glucans and melanin are also constitutive of the ECM in aspergilloma but not in invasive aspergillosis. In vitro, two biofilm models were established to mimic the in vivo situation. The first model (model 1) uses submerged liquid conditions and is characterized by slow growth, while the second model (model 2) uses agar medium and aerial conditions and is characterized by rapid growth. The composition of the ECM was studied only in the second model and has been shown to be composed of galactomannan, galactosaminogalactan (GAG), and α1,3 glucans, melanin, antigens, and hydrophobins. The presence of extracellular DNA was detected in model 1 biofilm but not in model 2. Transcriptomic analysis employing both biofilm models showed upregulation of genes coding for proteins involved in the biosynthesis of secondary metabolites, adhesion, and drug resistance. However, most data on A. fumigatus biofilms have been obtained in vitro and should be confirmed using in vivo animal models. There is a need for new therapeutic antibiofilm strategies that focus on the use of combination therapy, since biofilm formation poses an important clinical problem due to their resistance to antifungal agents. Furthermore, in vivo investigations of A. fumigatus biofilms that incorporate the associated microbiota are needed. Such studies will add another layer of complexity to our understanding of the role of A. fumigatus biofilm during lung invasion.
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de Man TJB, Stajich JE, Kubicek CP, Teiling C, Chenthamara K, Atanasova L, Druzhinina IS, Levenkova N, Birnbaum SSL, Barribeau SM, Bozick BA, Suen G, Currie CR, Gerardo NM. Small genome of the fungus Escovopsis weberi, a specialized disease agent of ant agriculture. Proc Natl Acad Sci U S A 2016; 113:3567-72. [PMID: 26976598 PMCID: PMC4822581 DOI: 10.1073/pnas.1518501113] [Citation(s) in RCA: 49] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Many microorganisms with specialized lifestyles have reduced genomes. This is best understood in beneficial bacterial symbioses, where partner fidelity facilitates loss of genes necessary for living independently. Specialized microbial pathogens may also exhibit gene loss relative to generalists. Here, we demonstrate that Escovopsis weberi, a fungal parasite of the crops of fungus-growing ants, has a reduced genome in terms of both size and gene content relative to closely related but less specialized fungi. Although primary metabolism genes have been retained, the E. weberi genome is depleted in carbohydrate active enzymes, which is consistent with reliance on a host with these functions. E. weberi has also lost genes considered necessary for sexual reproduction. Contrasting these losses, the genome encodes unique secondary metabolite biosynthesis clusters, some of which include genes that exhibit up-regulated expression during host attack. Thus, the specialized nature of the interaction between Escovopsis and ant agriculture is reflected in the parasite's genome.
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Affiliation(s)
- Tom J B de Man
- Department of Biology, Emory University, Atlanta, GA 30322
| | - Jason E Stajich
- Department of Plant Pathology and Microbiology, University of California, Riverside, CA 92521
| | - Christian P Kubicek
- Institute of Chemical Engineering, Vienna University of Technology, 1060 Vienna, Austria
| | | | - Komal Chenthamara
- Institute of Chemical Engineering, Vienna University of Technology, 1060 Vienna, Austria
| | - Lea Atanasova
- Institute of Chemical Engineering, Vienna University of Technology, 1060 Vienna, Austria
| | - Irina S Druzhinina
- Institute of Chemical Engineering, Vienna University of Technology, 1060 Vienna, Austria
| | | | | | - Seth M Barribeau
- Department of Biology, Emory University, Atlanta, GA 30322; Department of Biology, East Carolina University, Greenville, NC 27858
| | | | - Garret Suen
- Department of Bacteriology, University of Wisconsin, Madison, WI 53706
| | - Cameron R Currie
- Department of Bacteriology, University of Wisconsin, Madison, WI 53706
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18
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Abstract
Only few Candida species, e.g., Candida albicans, Candida glabrata, Candida dubliniensis, and Candida parapsilosis, are successful colonizers of a human host. Under certain circumstances these species can cause infections ranging from superficial to life-threatening disseminated candidiasis. The success of C. albicans, the most prevalent and best studied Candida species, as both commensal and human pathogen depends on its genetic, biochemical, and morphological flexibility which facilitates adaptation to a wide range of host niches. In addition, formation of biofilms provides additional protection from adverse environmental conditions. Furthermore, in many host niches Candida cells coexist with members of the human microbiome. The resulting fungal-bacterial interactions have a major influence on the success of C. albicans as commensal and also influence disease development and outcome. In this chapter, we review the current knowledge of important survival strategies of Candida spp., focusing on fundamental fitness and virulence traits of C. albicans.
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Affiliation(s)
- Melanie Polke
- Research Group Microbial Immunology, Hans-Knoell-Institute, Jena, Germany; Department Microbial Pathogenicity Mechanisms, Hans-Knoell-Institute, Jena, Germany
| | - Bernhard Hube
- Department Microbial Pathogenicity Mechanisms, Hans-Knoell-Institute, Jena, Germany; Friedrich-Schiller-University, Jena, Germany; Center for Sepsis Control and Care, Jena University Hospital, Jena, Germany
| | - Ilse D Jacobsen
- Research Group Microbial Immunology, Hans-Knoell-Institute, Jena, Germany; Friedrich-Schiller-University, Jena, Germany
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19
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Kuznets G, Vigonsky E, Weissman Z, Lalli D, Gildor T, Kauffman SJ, Turano P, Becker J, Lewinson O, Kornitzer D. A relay network of extracellular heme-binding proteins drives C. albicans iron acquisition from hemoglobin. PLoS Pathog 2014; 10:e1004407. [PMID: 25275454 PMCID: PMC4183699 DOI: 10.1371/journal.ppat.1004407] [Citation(s) in RCA: 73] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 08/18/2014] [Indexed: 12/14/2022] Open
Abstract
Iron scavenging constitutes a crucial challenge for survival of pathogenic microorganisms in the iron-poor host environment. Candida albicans, like many microbial pathogens, is able to utilize iron from hemoglobin, the largest iron pool in the host's body. Rbt5 is an extracellular glycosylphosphatidylinositol (GPI)-anchored heme-binding protein of the CFEM family that facilitates heme-iron uptake by an unknown mechanism. Here, we characterize an additional C. albicans CFEM protein gene, PGA7, deletion of which elicits a more severe heme-iron utilization phenotype than deletion of RBT5. The virulence of the pga7−/− mutant is reduced in a mouse model of systemic infection, consistent with a requirement for heme-iron utilization for C. albicans pathogenicity. The Pga7 and Rbt5 proteins exhibit distinct cell wall attachment, and discrete localization within the cell envelope, with Rbt5 being more exposed than Pga7. Both proteins are shown here to efficiently extract heme from hemoglobin. Surprisingly, while Pga7 has a higher affinity for heme in vitro, we find that heme transfer can occur bi-directionally between Pga7 and Rbt5, supporting a model in which they cooperate in a heme-acquisition relay. Together, our data delineate the roles of Pga7 and Rbt5 in a cell surface protein network that transfers heme from extracellular hemoglobin to the endocytic pathway, and provide a paradigm for how receptors embedded in the cell wall matrix can mediate nutrient uptake across the fungal cell envelope. Candida albicans, a commensal fungus of human mucosal surfaces in healthy individuals, is a common cause of superficial infections, as well as of life-threatening systemic infections in individuals suffering from a reduced immune function. As a systemic pathogen, it has to cope with a scarcity of specific nutrients in the host environment, chief among them iron. To overcome this iron limitation, C. albicans is able to extract iron from heme and hemoglobin, the largest iron pools in the human body, via a pathway that involves endocytosis into the cell. Here we show that efficient heme uptake relies on a family of extracellularly-anchored proteins that serve as heme receptors, two of which, at least, are required for efficient heme utilization. Our data suggest the existence of a relay system that transfers heme from one protein to the next across the cell envelope, explaining the requirement for multiple heme receptors for efficient heme-iron utilization. This study extends our understanding of the pathway of host heme utilization by fungal pathogens, and provides new insights into the question of how nutrients such as heme cross the fungal cell wall.
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Affiliation(s)
- Galit Kuznets
- B. Rappaport Faculty of Medicine, Technion – I.I.T. and the Rappaport Institute for Research in the Medical Sciences, Haifa, Israel
| | - Elena Vigonsky
- B. Rappaport Faculty of Medicine, Technion – I.I.T. and the Rappaport Institute for Research in the Medical Sciences, Haifa, Israel
| | - Ziva Weissman
- B. Rappaport Faculty of Medicine, Technion – I.I.T. and the Rappaport Institute for Research in the Medical Sciences, Haifa, Israel
| | - Daniela Lalli
- CERM and Department of Chemistry, University of Florence, Sesto Fiorentino, Italy
| | - Tsvia Gildor
- B. Rappaport Faculty of Medicine, Technion – I.I.T. and the Rappaport Institute for Research in the Medical Sciences, Haifa, Israel
| | - Sarah J. Kauffman
- Microbiology Department, University of Tennessee, Knoxville, Tennessee, United States of America
| | - Paola Turano
- CERM and Department of Chemistry, University of Florence, Sesto Fiorentino, Italy
| | - Jeffrey Becker
- Microbiology Department, University of Tennessee, Knoxville, Tennessee, United States of America
| | - Oded Lewinson
- B. Rappaport Faculty of Medicine, Technion – I.I.T. and the Rappaport Institute for Research in the Medical Sciences, Haifa, Israel
| | - Daniel Kornitzer
- B. Rappaport Faculty of Medicine, Technion – I.I.T. and the Rappaport Institute for Research in the Medical Sciences, Haifa, Israel
- * E-mail:
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20
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Sherry L, Rajendran R, Lappin DF, Borghi E, Perdoni F, Falleni M, Tosi D, Smith K, Williams C, Jones B, Nile CJ, Ramage G. Biofilms formed by Candida albicans bloodstream isolates display phenotypic and transcriptional heterogeneity that are associated with resistance and pathogenicity. BMC Microbiol 2014; 14:182. [PMID: 24996549 PMCID: PMC4105547 DOI: 10.1186/1471-2180-14-182] [Citation(s) in RCA: 106] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Accepted: 06/24/2014] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Candida albicans infections have become increasingly recognised as being biofilm related. Recent studies have shown that there is a relationship between biofilm formation and poor clinical outcomes in patients infected with biofilm proficient strains. Here we have investigated a panel of clinical isolates in an attempt to evaluate their phenotypic and transcriptional properties in an attempt to differentiate and define levels of biofilm formation. RESULTS Biofilm formation was shown to be heterogeneous; with isolates being defined as either high or low biofilm formers (LBF and HBF) based on different biomass quantification. These categories could also be differentiated using a cell surface hydrophobicity assay with 24 h biofilms. HBF isolates were more resistance to amphotericin B (AMB) treatment than LBF, but not voriconazole (VRZ). In a Galleria mellonella model of infection HBF mortality was significantly increased in comparison to LBF. Histological analysis of the HBF showed hyphal elements intertwined indicative of the biofilm phenotype. Transcriptional analysis of 23 genes implicated in biofilm formation showed no significant differential expression profiles between LBF and HBF, except for Cdr1 at 4 and 24 h. Cluster analysis showed similar patterns of expression for different functional classes of genes, though correlation analysis of the 4 h biofilms with overall biomass at 24 h showed that 7 genes were correlated with high levels of biofilm, including Als3, Eap1, Cph1, Sap5, Plb1, Cdr1 and Zap1. CONCLUSIONS Our findings show that biofilm formation is variable amongst C. albicans isolates, and categorising isolates depending on this can be used to predict how pathogenic the isolate will behave clinically. We have shown that looking at individual genes in less informative than looking at multiple genes when trying to categorise isolates at LBF or HBF. These findings are important when developing biofilm-specific diagnostics as these could be used to predict how best to treat patients infected with C. albicans. Further studies are required to evaluate this clinically.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | - Gordon Ramage
- Infection and Immunity Research Group, Glasgow Dental School, School of Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, 378 Sauchiehall Street, Glasgow G2 3JZ, UK.
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21
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Pendleton AL, Smith KE, Feau N, Martin FM, Grigoriev IV, Hamelin R, Nelson CD, Burleigh JG, Davis JM. Duplications and losses in gene families of rust pathogens highlight putative effectors. FRONTIERS IN PLANT SCIENCE 2014; 5:299. [PMID: 25018762 PMCID: PMC4071342 DOI: 10.3389/fpls.2014.00299] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/01/2014] [Accepted: 06/06/2014] [Indexed: 05/20/2023]
Abstract
Rust fungi are a group of fungal pathogens that cause some of the world's most destructive diseases of trees and crops. A shared characteristic among rust fungi is obligate biotrophy, the inability to complete a lifecycle without a host. This dependence on a host species likely affects patterns of gene expansion, contraction, and innovation within rust pathogen genomes. The establishment of disease by biotrophic pathogens is reliant upon effector proteins that are encoded in the fungal genome and secreted from the pathogen into the host's cell apoplast or within the cells. This study uses a comparative genomic approach to elucidate putative effectors and determine their evolutionary histories. We used OrthoMCL to identify nearly 20,000 gene families in proteomes of 16 diverse fungal species, which include 15 basidiomycetes and one ascomycete. We inferred patterns of duplication and loss for each gene family and identified families with distinctive patterns of expansion/contraction associated with the evolution of rust fungal genomes. To recognize potential contributors for the unique features of rust pathogens, we identified families harboring secreted proteins that: (i) arose or expanded in rust pathogens relative to other fungi, or (ii) contracted or were lost in rust fungal genomes. While the origin of rust fungi appears to be associated with considerable gene loss, there are many gene duplications associated with each sampled rust fungal genome. We also highlight two putative effector gene families that have expanded in Cqf that we hypothesize have roles in pathogenicity.
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Affiliation(s)
- Amanda L. Pendleton
- Plant Molecular and Cellular Biology Program, University of FloridaGainesville, FL, USA
| | - Katherine E. Smith
- Southern Research Station, Southern Institute of Forest Genetics, USDA Forest ServiceSaucier, MS, USA
| | - Nicolas Feau
- Department of Forest Sciences, University of British ColumbiaVancouver, BC, Canada
| | - Francis M. Martin
- Interactions Arbres/Microorganismes, Laboratoire d'Excellence ARBRE, INRA-Nancy, UMR Institut National de la Recherche Agronomique – Université de LorraineChampenoux, France
| | - Igor V. Grigoriev
- US Department of Energy, Joint Genome InstituteWalnut Creek, CA, USA
| | - Richard Hamelin
- Department of Forest Sciences, University of British ColumbiaVancouver, BC, Canada
| | - C. Dana Nelson
- Southern Research Station, Southern Institute of Forest Genetics, USDA Forest ServiceSaucier, MS, USA
| | - J. Gordon Burleigh
- Plant Molecular and Cellular Biology Program, University of FloridaGainesville, FL, USA
- Biology Department, University of FloridaGainesville, FL, USA
- Genetics Institute, University of FloridaGainesville, FL, USA
| | - John M. Davis
- Plant Molecular and Cellular Biology Program, University of FloridaGainesville, FL, USA
- Genetics Institute, University of FloridaGainesville, FL, USA
- School of Forest Resources and Conservation, University of FloridaGainesville, FL, USA
- *Correspondence: John M. Davis, School of Forest Resources and Conservation, University of Florida, 365 Newins-Ziegler Hall, Gainesville, FL 32611, USA e-mail:
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Vaknin Y, Shadkchan Y, Levdansky E, Morozov M, Romano J, Osherov N. The three Aspergillus fumigatus CFEM-domain GPI-anchored proteins (CfmA-C) affect cell-wall stability but do not play a role in fungal virulence. Fungal Genet Biol 2013; 63:55-64. [PMID: 24361821 DOI: 10.1016/j.fgb.2013.12.005] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2013] [Revised: 12/10/2013] [Accepted: 12/11/2013] [Indexed: 10/25/2022]
Abstract
Fungal cell-wall proteins containing the conserved fungal CFEM domain have been implicated in host-pathogen interactions and virulence. To determine the role of these proteins in the mold pathogen Aspergillus fumigatus, we deleted the entire family of three CFEM-containing genes (CfmA-C), singly and in all combinations. We found an additive increase in the susceptibility of the single, double and triple ΔCfm mutants towards the chitin/β-glucan-microfibril destabilizing compounds Congo Red (CR) and Calcofluor White (CFW), indicating that the A. fumigatus CFEM proteins are involved in stabilizing the cell wall. No defects in growth or germination were observed, indicating that CFEM proteins do not have an essential role in the morphogenesis of A. fumigatus. Unlike in Candida albicans, the A. fumigatus CFEM proteins were not implicated in heme uptake or biofilm formation. The ΔTriple-Cfm deletion strain did not exhibit altered virulence in either insect or murine models of infection, suggesting that cell-wall proteins containing the conserved fungal CFEM domain are not a significant virulence factor in A. fumigatus.
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Affiliation(s)
- Yakir Vaknin
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Ramat-Aviv, Tel-Aviv, Israel
| | - Yana Shadkchan
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Ramat-Aviv, Tel-Aviv, Israel
| | - Emma Levdansky
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Ramat-Aviv, Tel-Aviv, Israel
| | - Michael Morozov
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Ramat-Aviv, Tel-Aviv, Israel
| | - Jacob Romano
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Ramat-Aviv, Tel-Aviv, Israel
| | - Nir Osherov
- Department of Clinical Microbiology and Immunology, Sackler School of Medicine, Ramat-Aviv, Tel-Aviv, Israel.
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23
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Staniszewska M, Bondaryk M, Swoboda-Kopec E, Siennicka K, Sygitowicz G, Kurzatkowski W. Candida albicans morphologies revealed by scanning electron microscopy analysis. Braz J Microbiol 2013; 44:813-21. [PMID: 24516422 PMCID: PMC3910194 DOI: 10.1590/s1517-83822013005000056] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2012] [Accepted: 09/10/2012] [Indexed: 12/26/2022] Open
Abstract
Scanning electron microscope (SEM) observations were used to analyze particular morphologies of Candida albicans clinical isolate (strain 82) and mutants defective in hyphae-promoting genes EFG1 (strain HLC52) and/or CPH1 (strains HLC54 and Can16). Transcription factors Efg1 and Cph1 play role in regulating filamentation and adhesion of C. albicans’ morphologies. Comparative analysis of such mutants and clinical isolate showed that Efg1 is required for human serum-induced cell growth and morphological switching. In the study, distinct differences between ultrastructural patterns of clinical strain’s and null mutants’ morphologies were observed (spherical vs tube-like blastoconidia, or solid and fragile constricted septa vs only the latter observed in strains with EFG1 deleted). In addition, wild type strain displayed smooth colonies of cells in comparison to mutants which exhibited wrinkled phenotype. It was observed that blastoconidia of clinical strain exhibited either polarly or randomly located budding. Contrariwise, morphotypes of mutants showed either multiple polar budding or a centrally located single bud scar (mother-daughter cell junction) distinguishing tube-like yeast/pseudohyphal growth (the length-to-width ratios larger than 1.5). In their planktonic form of growth, blastoconidia of clinical bloodstream isolate formed constitutively true hyphae under undiluted human serum inducing conditions. It was found that true hyphae are essential elements for developing structural integrity of conglomerate, as mutants displaying defects in their flocculation and conglomerate-forming abilities in serum. While filamentation is an important virulence trait in C. albicans the true hyphae are the morphologies which may be expected to play a role in bloodstream infections.
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Affiliation(s)
- M Staniszewska
- National Institute of Public Health, National Institute of Hygiene, Independent Laboratory of Streptomyces and Fungi Imperfecti, Warsaw, Poland
| | - M Bondaryk
- National Institute of Public Health, National Institute of Hygiene, Independent Laboratory of Streptomyces and Fungi Imperfecti, Warsaw, Poland
| | - E Swoboda-Kopec
- Department of Microbiology, Medical University of Warsaw, Poland
| | | | - G Sygitowicz
- Department of Biochemistry and Clinical Chemistry, Medical University of Warsaw, Poland
| | - W Kurzatkowski
- National Institute of Public Health, National Institute of Hygiene, Independent Laboratory of Streptomyces and Fungi Imperfecti, Warsaw, Poland
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24
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Kronstad JW, Cadieux B, Jung WH. Pathogenic yeasts deploy cell surface receptors to acquire iron in vertebrate hosts. PLoS Pathog 2013; 9:e1003498. [PMID: 24009498 PMCID: PMC3757031 DOI: 10.1371/journal.ppat.1003498] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022] Open
Affiliation(s)
- James W Kronstad
- The Michael Smith Laboratories, Department of Microbiology and Immunology, University of British Columbia, Vancouver, British Columbia, Canada.
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25
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Identification of genes upregulated by the transcription factor Bcr1 that are involved in impermeability, impenetrability, and drug resistance of Candida albicans a/α biofilms. EUKARYOTIC CELL 2013; 12:875-88. [PMID: 23563485 DOI: 10.1128/ec.00071-13] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Candida albicans forms two types of biofilm, depending upon the configuration of the mating type locus. Although architecturally similar, a/α biofilms are impermeable, impenetrable, and drug resistant, whereas a/a and α/α biofilms lack these traits. The difference appears to be the result of an alternative matrix. Overexpression in a/a cells of BCR1, a master regulator of the a/α matrix, conferred impermeability, impenetrability, and drug resistance to a/a biofilms. Deletion of BCR1 in a/α cells resulted in the loss of these a/α-specific biofilm traits. Using BCR1 overexpression in a/a cells, we screened 107 genes of interest and identified 8 that were upregulated by Bcr1. When each was overexpressed in a/a biofilms, the three a/α traits were partially conferred, and when each was deleted in a/α cells, the traits were partially lost. Five of the eight genes have been implicated in iron homeostasis, and six encode proteins that are either in the wall or plasma membrane or secreted. All six possess sites for O-linked and N-linked glycosylation that, like glycosylphosphatidylinositol (GPI) anchors, can cross-link to the wall and matrix, suggesting that they may exert a structural role in conferring impermeability, impenetrability, and drug resistance, in addition to their physiological functions. The fact that in a screen of 107 genes, all 8 of the Bcr1-upregulated genes identified play a role in impermeability, impenetrability, and drug resistance suggests that the formation of the a/α matrix is highly complex and involves a larger number of genes than the initial ones identified here.
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26
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Cuéllar-Cruz M, López-Romero E, Villagómez-Castro JC, Ruiz-Baca E. Candida species: new insights into biofilm formation. Future Microbiol 2012; 7:755-71. [PMID: 22702528 DOI: 10.2217/fmb.12.48] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Biofilms of Candida albicans, Candida parapsilosis, Candida glabrata and Candida tropicalis are associated with high indices of hospital morbidity and mortality. Major factors involved in the formation and growth of Candida biofilms are the chemical composition of the medical implant and the cell wall adhesins responsible for mediating Candida-Candida, Candida-human host cell and Candida-medical device adhesion. Strategies for elucidating the mechanisms that regulate the formation of Candida biofilms combine tools from biology, chemistry, nanoscience, material science and physics. This review proposes the use of new technologies, such as synchrotron radiation, to study the mechanisms of biofilm formation. In the future, this information is expected to facilitate the design of new materials and antifungal compounds that can eradicate nosocomial Candida infections due to biofilm formation on medical implants. This will reduce dissemination of candidiasis and hopefully improve the quality of life of patients.
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Affiliation(s)
- Mayra Cuéllar-Cruz
- Unidad de Biotecnología Médica & Farmacéutica, Centro de Investigación & Asistencia en Tecnología & Diseño del Estado de Jalisco, AC, Guadalajara, Jalisco, México.
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27
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Druzhinina IS, Shelest E, Kubicek CP. Novel traits of Trichoderma predicted through the analysis of its secretome. FEMS Microbiol Lett 2012; 337:1-9. [PMID: 22924408 PMCID: PMC3533174 DOI: 10.1111/j.1574-6968.2012.02665.x] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Revised: 08/22/2012] [Accepted: 08/22/2012] [Indexed: 01/05/2023] Open
Abstract
Mycotrophic species of Trichoderma are among the most common fungi isolated from free soil, dead wood and as parasites on sporocarps of other fungi (mycoparasites). In addition, they undergo various other biotrophic associations ranging from rhizosphere colonization and endophytism up to facultative pathogenesis on such animals as roundworms and humans. Together with occurrence on a variety of less common substrata (marine invertebrates, artificial materials, indoor habitats), these lifestyles illustrate a wealthy opportunistic potential of the fungus. One tropical species, Trichoderma reesei, has become a prominent producer of cellulases and hemicellulases, whereas several other species are applied in agriculture for the biological control of phytopathogenic fungi. The sequencing of the complete genomes of the three species (T. reesei, T. virens, and T. atroviride) has led to a deepened understanding of Trichoderma lifestyle and its molecular physiology. In this review, we present the in silico predicted secretome of Trichoderma, and – in addition to the unique features of carbohydrate active enzymes – demonstrate the importance of such protein families as proteases, oxidative enzymes, and small cysteine-rich proteins, all of that received little attention in Trichoderma genetics so far. We also discuss the link between Trichoderma secretome and biology of the fungus.
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Affiliation(s)
- Irina S Druzhinina
- Research Division Biotechnology and Microbiology, Institute of Chemical Engineering, Vienna University of Technology, Vienna, Austria
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28
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Ramage G, Rajendran R, Gutierrez-Correa M, Jones B, Williams C. Aspergillus biofilms: clinical and industrial significance. FEMS Microbiol Lett 2011; 324:89-97. [PMID: 22092808 DOI: 10.1111/j.1574-6968.2011.02381.x] [Citation(s) in RCA: 87] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2011] [Revised: 08/09/2011] [Accepted: 08/09/2011] [Indexed: 11/30/2022] Open
Abstract
The biofilm phenotype is an increasingly important concept in mycological research. Recently, there has been a developing interest in whether Aspergillus species are truly able to form biofilms or not. Industrial mycologists have long been aware of biofilms and their benefit in fermentation processes, whereas clinically their role is uncertain. This review provides an update on the impact that Aspergillus biofilms have medically and industrially, and will discuss biofilm development, and our current understanding of its molecular basis. The role of exopolymeric substance and how this substance relates to antimicrobial recalcitrance will also be discussed.
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Affiliation(s)
- Gordon Ramage
- School of Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, UK.
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29
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Laforet L, Moreno I, Sánchez-Fresneda R, Martínez-Esparza M, Martínez JP, Argüelles JC, de Groot PWJ, Valentín-Gomez E. Pga26 mediates filamentation and biofilm formation and is required for virulence in Candida albicans. FEMS Yeast Res 2011; 11:389-97. [PMID: 21439008 DOI: 10.1111/j.1567-1364.2011.00727.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
The Candida albicans gene PGA26 encodes a small cell wall protein and is upregulated during de novo wall synthesis in protoplasts. Disruption of PGA26 caused hypersensitivity to cell wall-perturbing compounds (Calcofluor white and Congo red) and to zymolyase, which degrades the cell wall β-1,3-glucan network. However, susceptibility to caspofungin, an inhibitor of β-1,3-glucan synthesis, was decreased. In addition, pga26Δ mutants show increased susceptibility to antifungals (fluconazol, posaconazol or amphotericin B) that target the plasma membrane and have altered sensitivities to environmental (heat, osmotic and oxidative) stresses. Except for a threefold increase in β-1,6-glucan and a slightly widened outer mannoprotein layer, the cell wall composition and structure was largely unaltered. Therefore, Pga26 is important for proper cell wall integrity, but does not seem to be directly involved in the synthesis of cell wall components. Deletion of PGA26 further leads to hyperfilamentation, increased biofilm formation and reduced virulence in a mouse model of disseminated candidiasis. We propose that deletion of PGA26 may cause an imbalance in the morphological switching ability of Candida, leading to attenuated dissemination and infection.
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Affiliation(s)
- Leslie Laforet
- Departamento de Microbiología y Ecología, Universidad de Valencia, Burjassot, Spain
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