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Goughenour K, Creech A, Xu J, He X, Hissong R, Giamberardino C, Tenor J, Toffaletti D, Perfect J, Olszewski M. Cryptococcus neoformans trehalose-6-phosphate synthase (tps1) promotes organ-specific virulence and fungal protection against multiple lines of host defenses. Front Cell Infect Microbiol 2024; 14:1392015. [PMID: 38841113 PMCID: PMC11150607 DOI: 10.3389/fcimb.2024.1392015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Accepted: 04/04/2024] [Indexed: 06/07/2024] Open
Abstract
Trehalose-6-phosphate synthase (TPS1) was identified as a virulence factor for Cryptococcus neoformans and a promising therapeutic target. This study reveals previously unknown roles of TPS1 in evasion of host defenses during pulmonary and disseminated phases of infection. In the pulmonary infection model, TPS1-deleted (tps1Δ) Cryptococci are rapidly cleared by mouse lungs whereas TPS1-sufficent WT (H99) and revertant (tps1Δ:TPS1) strains expand in the lungs and disseminate, causing 100% mortality. Rapid pulmonary clearance of tps1Δ mutant is T-cell independent and relies on its susceptibility to lung resident factors and innate immune factors, exemplified by tps1Δ but not H99 inhibition in a coculture with dispersed lung cells and its rapid clearance coinciding with innate leukocyte infiltration. In the disseminated model of infection, which bypasses initial lung-fungus interactions, tps1Δ strain remains highly attenuated. Specifically, tps1Δ mutant is unable to colonize the lungs from the bloodstream or expand in spleens but is capable of crossing into the brain, where it remains controlled even in the absence of T cells. In contrast, strains H99 and tps1Δ:TPS1 rapidly expand in all studied organs, leading to rapid death of the infected mice. Since the rapid pulmonary clearance of tps1Δ mutant resembles a response to acapsular strains, the effect of tps1 deletion on capsule formation in vitro and in vivo was examined. Tps1Δ cryptococci form capsules but with a substantially reduced size. In conclusion, TPS1 is an important virulence factor, allowing C. neoformans evasion of resident pulmonary and innate defense mechanisms, most likely via its role in cryptococcal capsule formation.
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Affiliation(s)
- Kristie Goughenour
- Research Service, Lieutenant Colonel Charles S. Kettles VA Medical Center, Ann Arbor, MI, United States
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan, Ann Arbor, MI, United States
| | - Arianna Creech
- Research Service, Lieutenant Colonel Charles S. Kettles VA Medical Center, Ann Arbor, MI, United States
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan, Ann Arbor, MI, United States
| | - Jintao Xu
- Research Service, Lieutenant Colonel Charles S. Kettles VA Medical Center, Ann Arbor, MI, United States
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan, Ann Arbor, MI, United States
| | - Xiumiao He
- Research Service, Lieutenant Colonel Charles S. Kettles VA Medical Center, Ann Arbor, MI, United States
| | - Rylan Hissong
- Research Service, Lieutenant Colonel Charles S. Kettles VA Medical Center, Ann Arbor, MI, United States
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan, Ann Arbor, MI, United States
| | - Charles Giamberardino
- Division of Infectious Diseases, Department of Medicine, Duke University, Durham, NC, United States
| | - Jennifer Tenor
- Division of Infectious Diseases, Department of Medicine, Duke University, Durham, NC, United States
| | - Dena Toffaletti
- Division of Infectious Diseases, Department of Medicine, Duke University, Durham, NC, United States
| | - John Perfect
- Division of Infectious Diseases, Department of Medicine, Duke University, Durham, NC, United States
| | - Michal Olszewski
- Research Service, Lieutenant Colonel Charles S. Kettles VA Medical Center, Ann Arbor, MI, United States
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2
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de Oliveira HC, Santos MDM, Camillo-Andrade AC, Castelli RF, Dos Reis FCG, Carvalho PC, Rodrigues ML. Proteomics reveals that the antifungal activity of fenbendazole against Cryptococcus neoformans requires protein kinases. Int J Antimicrob Agents 2024; 63:107157. [PMID: 38548248 DOI: 10.1016/j.ijantimicag.2024.107157] [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: 11/20/2023] [Revised: 02/09/2024] [Accepted: 03/21/2024] [Indexed: 04/20/2024]
Abstract
Cryptococcus neoformans is responsible for over 100 000 deaths annually, and the treatment of this fungal disease is expensive and not consistently effective. Unveiling new therapeutic avenues is crucial. Previous studies have suggested that the anthelmintic drug fenbendazole is an affordable and nontoxic candidate to combat cryptococcosis. However, its mechanism of anticryptococcal activity has been only superficially investigated. In this study, we examined the global cellular response of C. neoformans to fenbendazole using a proteomic approach (data are available via ProteomeXchange with identifier PXD047041). Fenbendazole treatment mostly impacted the abundance of proteins related to metabolic pathways, RNA processing, and intracellular traffic. Protein kinases, in particular, were significantly affected by fenbendazole treatment. Experimental validation of the proteomics data using a collection of C. neoformans mutants led to the identification of critical roles of five protein kinases in fenbendazole's antifungal activity. In fact, mutants lacking the expression of genes encoding Chk1, Tco2, Tco3, Bub1, and Sch9 kinases demonstrated greater resistance to fenbendazole compared to wild-type cells. In combination with the standard antifungal drug amphotericin B, fenbendazole reduced the cryptococcal burden in mice. These findings not only contribute to the elucidation of fenbendazole's mode of action but also support its use in combination therapy with amphotericin B. In conclusion, our data suggest that fenbendazole holds promise for further development as an anticryptococcal agent.
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Affiliation(s)
| | - Marlon D M Santos
- Instituto Carlos Chagas, Fundação Oswaldo Cruz (Fiocruz), Curitiba, Brazil; Analytical Biochemistry and Proteomics Unit. IIBCE/Institut Pasteur de Montevideo, Uruguay
| | - Amanda C Camillo-Andrade
- Instituto Carlos Chagas, Fundação Oswaldo Cruz (Fiocruz), Curitiba, Brazil; Analytical Biochemistry and Proteomics Unit. IIBCE/Institut Pasteur de Montevideo, Uruguay
| | - Rafael F Castelli
- Instituto Carlos Chagas, Fundação Oswaldo Cruz (Fiocruz), Curitiba, Brazil
| | - Flavia C G Dos Reis
- Instituto Carlos Chagas, Fundação Oswaldo Cruz (Fiocruz), Curitiba, Brazil; Centro de Desenvolvimento Tecnológico em Saúde (CDTS), Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Paulo C Carvalho
- Instituto Carlos Chagas, Fundação Oswaldo Cruz (Fiocruz), Curitiba, Brazil
| | - Marcio L Rodrigues
- Instituto Carlos Chagas, Fundação Oswaldo Cruz (Fiocruz), Curitiba, Brazil; Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
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3
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Silva VKA, Min S, Yoo K, Fries BC. Host-Pathogen Interactions and Correlated Factors That Are Affected in Replicative-Aged Cryptococcus neoformans. J Fungi (Basel) 2024; 10:279. [PMID: 38667950 PMCID: PMC11050866 DOI: 10.3390/jof10040279] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2024] [Revised: 03/27/2024] [Accepted: 04/04/2024] [Indexed: 04/28/2024] Open
Abstract
Cryptococcus neoformans is a facultative intracellular fungal pathogen. Ten-generation-old (10GEN) C. neoformans cells are more resistant to phagocytosis and killing by macrophages than younger daughter cells. However, mechanisms that mediate this resistance and intracellular parasitism are poorly understood. Here, we identified important factors for the intracellular survival of 10GEN C. neoformans, such as urease activity, capsule synthesis, and DNA content using flow cytometry and fluorescent microscopy techniques. The real-time visualization of time-lapse imaging was applied to determine the phagosomal acidity, membrane permeability, and vomocytosis (non-lytic exocytosis) rate in J774 macrophages that phagocytosed C. neoformans of different generational ages. Our results showed that old C. neoformans exhibited higher urease activity and enhanced Golgi activity. In addition, old C. neoformans were more likely to be arrested in the G2 phase, resulting in the occasional formation of aberrant trimera-like cells. To finish, the advanced generational age of the yeast cells slightly reduced vomocytosis events within host cells, which might be associated with increased phagolysosome pH and membrane permeability. Altogether, our results suggest that old C. neoformans prevail within acidic phagolysosomes and can manipulate the phagosome pH. These strategies may be used by old C. neoformans to resist phagosomal killing and drive cryptococcosis pathogenesis. The comprehension of these essential host-pathogen interactions could further shed light on mechanisms that bring new insights for novel antifungal therapeutic design.
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Affiliation(s)
- Vanessa K. A. Silva
- Division of Infectious Diseases, Department of Medicine, Stony Brook University, Stony Brook, NY 11794, USA; (V.K.A.S.); (S.M.)
| | - Sungyun Min
- Division of Infectious Diseases, Department of Medicine, Stony Brook University, Stony Brook, NY 11794, USA; (V.K.A.S.); (S.M.)
| | - Kyungyoon Yoo
- Department of Microbiology and Immunology, Renaissance School of Medicine, Stony Brook University, Stony Brook, NY 11794, USA;
| | - Bettina C. Fries
- Division of Infectious Diseases, Department of Medicine, Stony Brook University, Stony Brook, NY 11794, USA; (V.K.A.S.); (S.M.)
- Department of Microbiology and Immunology, Renaissance School of Medicine, Stony Brook University, Stony Brook, NY 11794, USA;
- Veterans Administration Medical Center, Northport, NY 11768, USA
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4
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Gutierrez-Gongora D, Woods M, Prosser RS, Geddes-McAlister J. Natural compounds from freshwater mussels disrupt fungal virulence determinants and influence fluconazole susceptibility in the presence of macrophages in Cryptococcus neoformans. Microbiol Spectr 2024; 12:e0284123. [PMID: 38329361 PMCID: PMC10913472 DOI: 10.1128/spectrum.02841-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2023] [Accepted: 01/12/2024] [Indexed: 02/09/2024] Open
Abstract
Cryptococcus neoformans is a human fungal pathogen responsible for fatal infections, especially in patients with a depressed immune system. Overexposure to antifungal drugs due to prolonged treatment regimens and structure-similar applications in agriculture have weakened the efficacy of current antifungals in the clinic. The rapid evolution of antifungal resistance urges the discovery of new compounds that inhibit fungal virulence determinants, rather than directly killing the pathogen, as alternative strategies to overcome disease and reduce selective pressure toward resistance. Here, we evaluated the efficacy of freshwater mussel extracts (crude and clarified) against the production of well-defined virulence determinants (i.e., thermotolerance, melanin, capsule, and biofilm) and fluconazole resistance in C. neoformans. We demonstrated the extracts' influence on fungal thermotolerance, capsule production, and biofilm formation, as well as susceptibility to fluconazole in the presence of macrophages. Additionally, we measured the inhibitory activity of extracts against commercial peptidases (family representatives of cryptococcal orthologs) related to fungal virulence determinants and fluconazole resistance, and integrated these phenotypic findings with quantitative proteomics profiling. Our approach defined distinct signatures of each treatment and validated a new mechanism of anti-virulence action toward the polysaccharide capsule from a selected extract following fractionation. By understanding the mechanisms driving the antifungal activity of mussels, we may develop innovative treatment options to overcome fungal infections and promote susceptibility to fluconazole in resistant strains. IMPORTANCE As the prevalence and severity of global fungal infections rise, along with an increasing incidence of antifungal resistance, new strategies to combat fungal pathogens and overcome resistance are urgently needed. Critically, our current methods to overcome fungal infections are limited and drive the evolution of resistance forward; however, an anti-virulence approach to disarm virulence factors of the pathogen and promote host cell clearance is promising. Here, we explore the efficacy of natural compounds derived from freshwater mussels against classical fungal virulence determinants, including thermotolerance, capsule production, stress response, and biofilm formation. We integrate our phenotypic discoveries with state-of-the-art mass spectrometry-based proteomics to identify mechanistic drivers of these antifungal properties and propose innovative avenues to reduce infection and support the treatment of resistant strains.
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Affiliation(s)
| | - Michael Woods
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario, Canada
| | - Ryan S. Prosser
- School of Environmental Sciences, University of Guelph, Guelph, Ontario, Canada
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Tugume L, Ssebambulidde K, Kasibante J, Ellis J, Wake RM, Gakuru J, Lawrence DS, Abassi M, Rajasingham R, Meya DB, Boulware DR. Cryptococcal meningitis. Nat Rev Dis Primers 2023; 9:62. [PMID: 37945681 DOI: 10.1038/s41572-023-00472-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/09/2023] [Indexed: 11/12/2023]
Abstract
Cryptococcus neoformans and Cryptococcus gattii species complexes cause meningoencephalitis with high fatality rates and considerable morbidity, particularly in persons with deficient T cell-mediated immunity, most commonly affecting people living with HIV. Whereas the global incidence of HIV-associated cryptococcal meningitis (HIV-CM) has decreased over the past decade, cryptococcosis still accounts for one in five AIDS-related deaths globally due to the persistent burden of advanced HIV disease. Moreover, mortality remains high (~50%) in low-resource settings. The armamentarium to decrease cryptococcosis-associated mortality is expanding: cryptococcal antigen screening in the serum and pre-emptive azole therapy for cryptococcal antigenaemia are well established, whereas enhanced pre-emptive combination treatment regimens to improve survival of persons with cryptococcal antigenaemia are in clinical trials. Short courses (≤7 days) of amphotericin-based therapy combined with flucytosine are currently the preferred options for induction therapy of cryptococcal meningitis. Whether short-course induction regimens improve long-term morbidity such as depression, reduced neurocognitive performance and physical disability among survivors is the subject of further study. Here, we discuss underlying immunology, changing epidemiology, and updates on the management of cryptococcal meningitis with emphasis on HIV-associated disease.
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Affiliation(s)
- Lillian Tugume
- Infectious Diseases Institute, Makerere University, Kampala, Uganda.
| | - Kenneth Ssebambulidde
- Infectious Diseases Institute, Makerere University, Kampala, Uganda
- Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, MD, USA
| | - John Kasibante
- Infectious Diseases Institute, Makerere University, Kampala, Uganda
| | - Jayne Ellis
- Infectious Diseases Institute, Makerere University, Kampala, Uganda
- Clinical Research Department, Faculty of Infectious and Tropical Diseases London School of Hygiene and Tropical Medicine, London, UK
| | - Rachel M Wake
- Institute for Infection and Immunity, St George's University of London, London, UK
| | - Jane Gakuru
- Infectious Diseases Institute, Makerere University, Kampala, Uganda
| | - David S Lawrence
- Clinical Research Department, Faculty of Infectious and Tropical Diseases London School of Hygiene and Tropical Medicine, London, UK
- Botswana Harvard AIDS Institute Partnership, Gaborone, Botswana
| | - Mahsa Abassi
- Department of Medicine, University of Minnesota, Minneapolis, MN, USA
| | - Radha Rajasingham
- Department of Medicine, University of Minnesota, Minneapolis, MN, USA
| | - David B Meya
- Infectious Diseases Institute, Makerere University, Kampala, Uganda
- Department of Medicine, University of Minnesota, Minneapolis, MN, USA
| | - David R Boulware
- Department of Medicine, University of Minnesota, Minneapolis, MN, USA
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6
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Ueno K, Nagamori A, Honkyu NO, Kataoka M, Shimizu K, Chang YC, Kwon-Chung KJ, Miyazaki Y. Cryptococcus neoformans requires the TVF1 gene for thermotolerance and virulence. Med Mycol 2023; 61:myad101. [PMID: 37818721 PMCID: PMC10565887 DOI: 10.1093/mmy/myad101] [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: 07/11/2023] [Revised: 09/13/2023] [Accepted: 09/26/2023] [Indexed: 09/29/2023] Open
Abstract
Cryptococcus neoformans is the primary causative agent of cryptococcosis. Since C. neoformans thrives in environments and its optimal growth temperature is 25-30°C, it needs to adapt to heat stress in order to cause infection in mammalian hosts. In this study, we aimed to investigate the role of an uncharacterized gene, CNAG_03308. Although the CNAG_03308 deletion strain grew as well as the parent strain KN99, it produced yeast cells with abnormal morphology at 37°C and failed to propagate at 39°C. Furthermore, the deletion strain exhibited slower growth at 37°C in the presence of congo red, which is a cell wall stressor. When cultured at 39°C, the deletion strain showed strong staining with fluorescent probes for cell wall chitin and chitosan, including FITC-labeled wheat germ agglutinin, Eosin Y, and calcofluor white. The transmission electron microscopy of the deletion strain revealed a thickened inner layer of the cell wall containing chitin and chitosan under heat stress. This cell-surface altered deletion strain induced dendritic cells to secrete more interleukin (IL)-6 and IL-23 than the control strains under heat stress. In a murine infection study, C57BL/6 mice infected with the deletion strain exhibited lower mortality and lower fungal burden in the lungs and brain compared to those infected with the control strains. Based on these findings, we concluded that CNAG_03308 gene is necessary for C. neoformans to adapt to heat stress both in vitro and in the host environment. Therefore, we designated the CNAG_03308 gene as TVF1, which stands for thermotolerance and virulence-related factor 1.
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Affiliation(s)
- Keigo Ueno
- Department of Fungal Infection, National Institute of Infectious Diseases, Tokyo 162-8640, Japan
| | - Akiko Nagamori
- Department of Fungal Infection, National Institute of Infectious Diseases, Tokyo 162-8640, Japan
| | - Nahoko Oniyama Honkyu
- Department of Fungal Infection, National Institute of Infectious Diseases, Tokyo 162-8640, Japan
| | - Michiyo Kataoka
- Department of Pathology, National Institute of Infectious Diseases, Tokyo 162-8640, Japan
| | - Kiminori Shimizu
- Department of Biological Science and Technology, Tokyo University of Science, Tokyo 125-8585, Japan
| | - Yun C Chang
- Molecular Microbiology Section, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Kyung J Kwon-Chung
- Molecular Microbiology Section, Laboratory of Clinical Immunology and Microbiology, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA
| | - Yoshitsugu Miyazaki
- Department of Fungal Infection, National Institute of Infectious Diseases, Tokyo 162-8640, Japan
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7
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Ullah A, Huang Y, Zhao K, Hua Y, Ullah S, Rahman MU, Wang J, Wang Q, Hu X, Zheng L. Characteristics and potential clinical applications of the extracellular vesicles of human pathogenic Fungi. BMC Microbiol 2023; 23:227. [PMID: 37598156 PMCID: PMC10439556 DOI: 10.1186/s12866-023-02945-3] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 07/14/2023] [Indexed: 08/21/2023] Open
Abstract
Extracellular vesicles (EVs) are a heterogeneous group of lipid membrane-enclosed compartments that contain different biomolecules and are released by almost all living cells, including fungal genera. Fungal EVs contain multiple bioactive components that perform various biological functions, such as stimulation of the host immune system, transport of virulence factors, induction of biofilm formation, and mediation of host-pathogen interactions. In this review, we summarize the current knowledge on EVs of human pathogenic fungi, mainly focusing on their biogenesis, composition, and biological effects. We also discuss the potential markers and therapeutic applications of fungal EVs.
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Affiliation(s)
- Amir Ullah
- Department of Laboratory Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, People's Republic of China
| | - Yiyi Huang
- Department of Laboratory Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, People's Republic of China
| | - Kening Zhao
- Department of Laboratory Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, People's Republic of China
- La Trobe Institute for Molecular Science, La Trobe University, Melbourne, Australia
| | - Yuneng Hua
- Center for Clinical Laboratory, Zhujiang Hospital, Southern Medical University, Guangzhou, People's Republic of China
| | - Shafi Ullah
- Department of pharmacy, COMSATS University Islamabad, Abbottabad Campus, Abbottabad, Pakistan
| | - Mujeeb Ur Rahman
- Biofuels Institute, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang, China
| | - Jingyu Wang
- Department of Laboratory Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, People's Republic of China
| | - Qian Wang
- Center for Clinical Laboratory, Zhujiang Hospital, Southern Medical University, Guangzhou, People's Republic of China.
| | - Xiumei Hu
- Department of Laboratory Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, People's Republic of China.
| | - Lei Zheng
- Department of Laboratory Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, People's Republic of China.
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8
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De Jesus DFF, De Freitas ALD, De Oliveira IM, De Almeida LC, Bastos RW, Spadari CDC, Melo ASDA, Santos DDA, Costa-Lotufo LV, Reis FCG, Rodrigues ML, Stefani HA, Ishida K. Organoselenium Has a Potent Fungicidal Effect on Cryptococcus neoformans and Inhibits the Virulence Factors. Antimicrob Agents Chemother 2023; 67:e0075922. [PMID: 36815840 PMCID: PMC10019174 DOI: 10.1128/aac.00759-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Accepted: 01/14/2023] [Indexed: 02/24/2023] Open
Abstract
Cryptococcosis therapy is often limited by toxicity problems, antifungal tolerance, and high costs. Studies approaching chalcogen compounds, especially those containing selenium, have shown promising antifungal activity against pathogenic species. This work aimed to evaluate the in vitro and in vivo antifungal potential of organoselenium compounds against Cryptococcus neoformans. The lead compound LQA_78 had an inhibitory effect on C. neoformans planktonic cells and dispersed cells from mature biofilms at similar concentrations. The fungal growth inhibition led to an increase in budding cells arrested in the G2/M phase, but the compound did not significantly affect structural cell wall components or chitinase activity, an enzyme that regulates the dynamics of the cell wall. The compound also inhibited titan cell (Tc) and enlarged capsule yeast (NcC) growth and reduced the body diameter and capsule thickness associated with increased capsular permeability of both virulent morphotypes. LQA_78 also reduced fungal melanization through laccase activity inhibition. The fungicidal activity was observed at higher concentrations (16 to 64 μg/mL) and may be associated with augmented plasma membrane permeability, ROS production, and loss of mitochondrial membrane potential. While LQA_78 is a nonhemolytic compound, its cytotoxic effects were cell type dependent, exhibiting no toxicity on Galleria mellonella larvae at a dose ≤46.5 mg/kg. LQA_78 treatment of larvae infected with C. neoformans effectively reduced the fungal burden and inhibited virulent morphotype formation. To conclude, LQA_78 displays fungicidal action and inhibits virulence factors of C. neoformans. Our results highlight the potential use of LQA_78 as a lead molecule for developing novel pharmaceuticals for treating cryptococcosis.
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Affiliation(s)
| | | | | | | | - Rafael Wesley Bastos
- Center of Biosciences, Federal University of Rio Grande do Norte (UFRN), Natal, Brazil
| | | | | | - Daniel de Assis Santos
- Institute of Biomedical Sciences, Federal University of Minas Gerais (UFMG), Belo Horizonte, Brazil
| | | | - Flavia C. G. Reis
- Carlos Chagas Institute, Oswaldo Cruz Foundation, Curitiba, Brazil
- Center for Technological Development in Health (CDTS), Oswaldo Cruz Foundation, Rio de Janeiro, Brazil
| | - Marcio L. Rodrigues
- Carlos Chagas Institute, Oswaldo Cruz Foundation, Curitiba, Brazil
- Institute of Microbiology Paulo de Góes, Federal University of Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | | | - Kelly Ishida
- Institute of Biomedical Sciences, University of São Paulo (USP), São Paulo, Brazil
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9
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de Oliveira HC, Castelli RF, Reis FCG, Samby K, Nosanchuk JD, Alves LR, Rodrigues ML. Screening of the Pandemic Response Box Reveals an Association between Antifungal Effects of MMV1593537 and the Cell Wall of Cryptococcus neoformans, Cryptococcus deuterogattii, and Candida auris. Microbiol Spectr 2022; 10:e0060122. [PMID: 35471056 PMCID: PMC9241760 DOI: 10.1128/spectrum.00601-22] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Accepted: 04/11/2022] [Indexed: 11/20/2022] Open
Abstract
There is an urgent unmet need for novel antifungals. In this study, we searched for novel antifungal activities in the Pandemic Response Box, a collection of 400 structurally diverse compounds in various phases of drug discovery. We identified five molecules which could control the growth of Cryptococcus neoformans, Cryptococcus deuterogattii, and the emerging global threat Candida auris. After eliminating compounds which demonstrated paradoxical antifungal effects or toxicity to mammalian macrophages, we selected compound MMV1593537 as a nontoxic, fungicidal molecule for further characterization of antifungal activity. Scanning electron microscopy revealed that MMV1593537 affected cellular division in all three pathogens. In Cryptococcus, MMV1593537 caused a reduction in capsular dimensions. Treatment with MMV1593537 resulted in increased detection of cell wall chitooligomers in these three species. Since chitooligomers are products of the enzymatic hydrolysis of chitin, we investigated whether surface chitinase activity was altered in response to MMV1593537 exposure. We observed peaks of enzyme activity in C. neoformans and C. deuterogattii in response to MMV1593537. We did not detect any surface chitinase activity in C. auris. Our results suggest that MMV1593537 is a promising, nontoxic fungicide whose mechanism of action, at least in Cryptococcus spp, requires chitinase-mediated hydrolysis of chitin. IMPORTANCE The development of novel antifungals is a matter of urgency. In this study, we evaluated antifungal activities in a collection of 400 molecules, using highly lethal fungal pathogens as targets. One of these molecules, namely, MMV1593537, was not toxic to host cells and controlled the growth of isolates of Cryptococcus neoformans, C. deuterogattii, C. gattii, Candida auris, C. albicans, C. parapsilosis, and C. krusei. We tested the mechanisms of antifungal action of MMV1593537 in the Cryptococcus and C. auris models and concluded that the compound affects the cell wall, a structure which is essential for fungal life. At least in Cryptococcus, this effect involved chitinase, an enzyme which is required for remodeling the cell wall. Our results suggest that MMV1593537 is a candidate for future antifungal development.
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Affiliation(s)
| | - Rafael F. Castelli
- Instituto Carlos Chagas, Fundação Oswaldo Cruz (Fiocruz), Curitiba, Brazil
- Programa de Pós-Graduação em Biologia Parasitária, Instituto Oswaldo Cruz, Fiocruz, Rio de Janeiro, Brazil
| | - Flavia C. G. Reis
- Instituto Carlos Chagas, Fundação Oswaldo Cruz (Fiocruz), Curitiba, Brazil
- Centro de Desenvolvimento Tecnológico em Saúde (CDTS), Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | | | - Joshua D. Nosanchuk
- Department of Microbiology and Immunology and Division of Infectious Diseases, Albert Einstein College of Medicine of Yeshiva University, New York, New York, USA
| | - Lysangela R. Alves
- Instituto Carlos Chagas, Fundação Oswaldo Cruz (Fiocruz), Curitiba, Brazil
| | - Marcio L. Rodrigues
- Instituto Carlos Chagas, Fundação Oswaldo Cruz (Fiocruz), Curitiba, Brazil
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
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10
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A Peptide from Budding Yeast GAPDH Serves as a Promising Antifungal against Cryptococcus neoformans. Microbiol Spectr 2022; 10:e0082621. [PMID: 35019693 PMCID: PMC8754130 DOI: 10.1128/spectrum.00826-21] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Infection of Cryptococcus neoformans is one of the leading causes of morbidity and mortality, particularly among immunocompromised patients. However, currently available drugs for the treatment of C. neoformans infection are minimal. Here, we report SP1, a peptide derived from glyceraldehyde-3-phosphate dehydrogenase (GAPDH) of Saccharomyces cerevisiae, efficiently kills C. neoformans and Cryptococcus gattii. SP1 causes damages to the capsule. Unlike many antimicrobial peptides, SP1 does not form pores on the cell membrane of C. neoformans. It interacts with membrane ergosterol and enters vacuole possibly through membrane trafficking. C. neoformans treated with SP1 show the apoptotic phenotypes such as imbalance of calcium ion homeostasis, reactive oxygen increment, phosphatidylserine exposure, and nuclear fragmentation. Our data imply that SP1 has the potential to be developed into a treatment option for cryptococcosis. IMPORTANCE Cryptococcus neoformans and Cryptococcus gattii can cause cryptococcosis, which has a high mortality rate. To treat the disease, amphotericin B and fluconazole are often used in clinic. However, amphotericin B has rather high renal toxicity, and tolerance to these drugs are quicky developed. The peptide SP1 derived from baker's yeast GAPDH shows antifungal function to kill Cryptococcus neoformans and Cryptococcus gattii efficiently with a high specificity, even for the drug-resistant strains. Our data demonstrate that SP1 induces the apoptosis-like death of Cryptococcus neoformans at low concentrations. The finding of this peptide may shed light on a new direction to treat cryptococcosis.
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Silva VKA, May RC, Rodrigues ML. Pyrifenox, an ergosterol inhibitor, differentially affects Cryptococcus neoformans and Cryptococcus gattii. Med Mycol 2021; 58:928-937. [PMID: 31915833 DOI: 10.1093/mmy/myz132] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2019] [Revised: 11/26/2019] [Accepted: 12/20/2019] [Indexed: 12/25/2022] Open
Abstract
Cryptococcosis is a life-threatening fungal infection. New therapeutic approaches are necessary to combat cryptococcosis, as the currently available therapeutic protocols are expensive and generally result in deleterious side effects. Pyrifenox is an antifungal compound that affects phytopathogens by inhibiting the biosynthesis of ergosterol. In this study, we investigated the effects of pyrifenox on Cryptococcus neoformans and Cryptococcus gattii growth, capsule architecture and export of the major capsule component, glucuroxylomannan (GXM). Pyrifenox inhibited the growth of C. neoformans, but was significantly less effective against C. gattii. The resistance of C. gattii to pyrifenox was associated with the expression of efflux pump genes, particularly AFR1 and AFR2, since mutant cells lacking expression of these genes became sensitive to pyrifenox. Analysis of the cryptococcal capsule by India ink counterstaining, immunofluorescence, and scanning electron microscopy showed that pyrifenox affected capsular dimensions in both species. However, GXM fibers were shorter and uniformly distributed in C. neoformans, whereas in C. gattii the number of fibers was reduced. Pyrifenox-treated C. gattii developed unusually long chains of undivided cells. The secretion of GXM was markedly reduced in both species after treatment with pyrifenox. Altogether, the results indicated that pyrifenox differently affects C. neoformans and C. gattii. In addition, it highlights a potential role for pyrifenox as an inhibitor of GXM export in experimental models involving pathogenic cryptococci.
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Affiliation(s)
- Vanessa K A Silva
- Programa de Pós-Graduação em Biologia Parasitária, Instituto Oswaldo Cruz (IOC), Fundação Oswaldo Cruz (FIOCRUZ), Rio de Janeiro, Brazil
| | - Robin C May
- Institute of Microbiology and Infection and School of Biosciences, University of Birmingham, Edgbaston, Birmingham, UK
| | - Marcio L Rodrigues
- Instituto Carlos Chagas (ICC), Fundação Oswaldo Cruz (FIOCRUZ), Curitiba, Brazil.,Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Brazil
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de Oliveira HC, Castelli RF, Reis FCG, Rizzo J, Rodrigues ML. Pathogenic Delivery: The Biological Roles of Cryptococcal Extracellular Vesicles. Pathogens 2020; 9:pathogens9090754. [PMID: 32948010 PMCID: PMC7557404 DOI: 10.3390/pathogens9090754] [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: 08/20/2020] [Revised: 09/13/2020] [Accepted: 09/15/2020] [Indexed: 12/12/2022] Open
Abstract
Extracellular vesicles (EVs) are produced by all domains of life. In fungi, these structures were first described in Cryptococcus neoformans and, since then, they were characterized in several pathogenic and non-pathogenic fungal species. Cryptococcal EVs participate in the export of virulence factors that directly impact the Cryptococcus-host interaction. Our knowledge of the biogenesis and pathogenic roles of Cryptococcus EVs is still limited, but recent methodological and scientific advances have improved our understanding of how cryptococcal EVs participate in both physiological and pathogenic events. In this review, we will discuss the importance of cryptococcal EVs, including early historical studies suggesting their existence in Cryptococcus, their putative mechanisms of biogenesis, methods of isolation, and possible roles in the interaction with host cells.
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Affiliation(s)
- Haroldo C. de Oliveira
- Instituto Carlos Chagas, Fundação Oswaldo Cruz (Fiocruz), Rua Prof. Algacyr Munhoz Mader, 3775 CIC Curitiba/PR, Curitiba 81350-010, Brasil; (H.C.d.O.); (R.F.C.); (F.C.G.R.)
| | - Rafael F. Castelli
- Instituto Carlos Chagas, Fundação Oswaldo Cruz (Fiocruz), Rua Prof. Algacyr Munhoz Mader, 3775 CIC Curitiba/PR, Curitiba 81350-010, Brasil; (H.C.d.O.); (R.F.C.); (F.C.G.R.)
- Programa de Pós-Graduação em Biologia Parasitária, Instituto Oswaldo Cruz, Fiocruz, Avenida Brasil, 4.365, Pavilhão Arthur Neiva–Manguinhos, Rio de Janeiro 21040-360, Brasil
| | - Flavia C. G. Reis
- Instituto Carlos Chagas, Fundação Oswaldo Cruz (Fiocruz), Rua Prof. Algacyr Munhoz Mader, 3775 CIC Curitiba/PR, Curitiba 81350-010, Brasil; (H.C.d.O.); (R.F.C.); (F.C.G.R.)
- Centro de Desenvolvimento Tecnológico em Saúde (CDTS), Fundação Oswaldo Cruz (Fiocruz), Av. Brasil, 4036–Prédio Da Expansão–8˚ Andar–Sala 814, Rio De Janeiro 21040-361, Brasil
| | - Juliana Rizzo
- Unité Biologie des ARN des Pathogènes Fongiques, Département de Mycologie, Institut Pasteur, 25-28 Rue du Dr Roux, 75015 Paris, France;
| | - Marcio L. Rodrigues
- Instituto Carlos Chagas, Fundação Oswaldo Cruz (Fiocruz), Rua Prof. Algacyr Munhoz Mader, 3775 CIC Curitiba/PR, Curitiba 81350-010, Brasil; (H.C.d.O.); (R.F.C.); (F.C.G.R.)
- Instituto de Microbiologia Paulo de Góes (IMPG), Universidade Federal do Rio de Janeiro, Cidade Universitária, Rio de Janeiro 21941-902, Brasil
- Correspondence:
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Rizzo J, Rodrigues ML, Janbon G. Extracellular Vesicles in Fungi: Past, Present, and Future Perspectives. Front Cell Infect Microbiol 2020; 10:346. [PMID: 32760680 PMCID: PMC7373726 DOI: 10.3389/fcimb.2020.00346] [Citation(s) in RCA: 77] [Impact Index Per Article: 19.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 06/05/2020] [Indexed: 12/21/2022] Open
Abstract
Extracellular vesicles (EVs) have garnered much interest in the cell biology and biomedical research fields. Many studies have reported the existence of EVs in all types of living cells, including in fifteen different fungal genera. EVs play diverse biological roles, from the regulation of physiological events and response to specific environmental conditions to the mediation of highly complex interkingdom communications. This review will provide a historical perspective on EVs produced by fungi and an overview of the recent discoveries in the field. We will also review the current knowledge about EV biogenesis and cargo, their role in cell-to-cell interactions, and methods of EV analysis. Finally, we will discuss the perspectives of EVs as vehicles for the delivery of biologically active molecules.
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Affiliation(s)
- Juliana Rizzo
- Unité Biologie des ARN des Pathogènes Fongiques, Département de Mycologie, Institut Pasteur, Paris, France
| | - Marcio L. Rodrigues
- Instituto Carlos Chagas, Fundação Oswaldo Cruz, Curitiba, Brazil
- Instituto de Microbiologia Paulo de Góes, Universidade Federal Do Rio de Janeiro (UFRJ), Rio de Janeiro, Brazil
| | - Guilhem Janbon
- Unité Biologie des ARN des Pathogènes Fongiques, Département de Mycologie, Institut Pasteur, Paris, France
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Bleackley MR, Dawson CS, Anderson MA. Fungal Extracellular Vesicles with a Focus on Proteomic Analysis. Proteomics 2019; 19:e1800232. [PMID: 30883019 DOI: 10.1002/pmic.201800232] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2018] [Revised: 02/17/2019] [Indexed: 12/26/2022]
Abstract
Extracellular vesicles (EVs) perform crucial functions in cell-cell communication. The packaging of biomolecules into membrane-enveloped vesicles prior to release into the extracellular environment provides a mechanism for coordinated delivery of multiple signals at high concentrations that is not achievable by classical secretion alone. Most of the understanding of the biosynthesis, composition, and function of EVs comes from mammalian systems. Investigation of fungal EVs, particularly those released by pathogenic yeast species, has revealed diverse cargo including proteins, lipids, nucleic acids, carbohydrates, and small molecules. Fungal EVs are proposed to function in a variety of biological processes including virulence and cell wall homeostasis with a focus on host-pathogen interactions. EVs also carry signals between fungal cells allowing for a coordinated attack on a host during infection. Research on fungal EVs in still in its infancy. Here a review of the literature thus far with a focus on proteomic analysis is provided with respect to techniques, results, and prospects.
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Affiliation(s)
- Mark R Bleackley
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Victoria, 3086, Australia
| | - Charlotte S Dawson
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Victoria, 3086, Australia
| | - Marilyn A Anderson
- Department of Biochemistry and Genetics, La Trobe Institute for Molecular Science, La Trobe University, Victoria, 3086, Australia
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15
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Rodrigues ML, Casadevall A. A two-way road: novel roles for fungal extracellular vesicles. Mol Microbiol 2018; 110:11-15. [PMID: 30079549 DOI: 10.1111/mmi.14095] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/30/2018] [Indexed: 01/25/2023]
Abstract
The biological functions of fungal extracellular vesicles (EVs) or exosomes have been mostly determined on the basis of the assumption that they are vehicles of trans-cell wall transport and molecular export. The possibility that fungal cells can bind to and internalize EVs remained largely unaddressed. Recent studies, however, demonstrated that fungal cells can internalize host-derived and/or fungal EVs through processes that profoundly modify their regular physiology. To illustrate this novel view, we discuss (i) the uptake of plant EVs by phytopathogenic fungi culminating in growth defects and virulence attenuation, (ii) the influence of EV internalization in prion transmission and biofilm formation in yeast cells, and (iii) the EV-mediated transfer of virulence in isolates of Cryptococcus gattii. These recent observations indicate that the functions exerted by EVs in fungal cells result from previously unknown mechanisms of bidirectional transport, opening new venues for the investigation of how EVs impact fungal physiology.
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Affiliation(s)
- Marcio L Rodrigues
- Instituto Carlos Chagas, Fundação Oswaldo Cruz (Fiocruz), Curitiba, Brazil.,Instituto de Microbiologia Paulo de Góes (IMPG), Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Arturo Casadevall
- Department of Molecular Microbiology and Immunology, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, USA
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Fonseca FL, Reis FCG, Sena BAG, Jozefowicz LJ, Kmetzsch L, Rodrigues ML. The Overlooked Glycan Components of the Cryptococcus Capsule. Curr Top Microbiol Immunol 2018; 422:31-43. [PMID: 30203395 DOI: 10.1007/82_2018_140] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Pathogenic species of Cryptococcus kill approximately 200,000 people each year. The most important virulence mechanism of C. neoformans and C. gattii, the causative agents of human and animal cryptococcosis, is the ability to form a polysaccharide capsule. Acapsular mutants of C. neoformans are avirulent in mice models of infection, and extracellularly released capsular polysaccharides are deleterious to the immune system. The principal capsular component in the Cryptococcus genus is a complex mannan substituted with xylosyl and glucuronyl units, namely glucuronoxylomannan (GXM). The second most abundant component of the cryptococcal capsule is a galactan with multiple glucuronyl, xylosyl, and mannosyl substitutions, namely glucuronoxylomannogalactan (GXMGal). The literature about the structure and functions of these two polysaccharides is rich, and a number of comprehensive reviews on this topic are available. Here, we focus our discussion on the less explored glycan components associated with the cryptococcal capsule, including mannoproteins and chitin-derived molecules. These glycans were selected for discussion on the basis that i) they have been consistently detected not only in the cell wall but also within the cryptococcal capsular network and ii) they have functions that impact immunological and/or pathogenic mechanisms in the Cryptococcus genus. The reported functions of these molecules strongly indicate that the biological roles of the cryptococcal capsule go far beyond the well-known properties of GXM and GXMGal.
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Affiliation(s)
- Fernanda L Fonseca
- Centro de Desenvolvimento Tecnológico Em Saúde (CDTS), Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Flavia C G Reis
- Instituto Carlos Chagas, Fundação Oswaldo Cruz (Fiocruz), Curitiba, Brazil
| | - Bianca A G Sena
- Instituto Carlos Chagas, Fundação Oswaldo Cruz (Fiocruz), Curitiba, Brazil
| | - Luísa J Jozefowicz
- Instituto Carlos Chagas, Fundação Oswaldo Cruz (Fiocruz), Curitiba, Brazil
| | - Livia Kmetzsch
- Centro de Biotecnologia, Universidade Federal Do Rio Grande Do Sul, Porto Alegre, Brazil.,Departamento de Biologia Molecular E Biotecnologia, Universidade Federal Do Rio Grande Do Sul, Porto Alegre, Brazil
| | - Marcio L Rodrigues
- Instituto Carlos Chagas, Fundação Oswaldo Cruz (Fiocruz), Curitiba, Brazil. .,Instituto de Microbiologia Paulo de Góes (IMPG), Universidade Federal Do Rio de Janeiro, Rio de Janeiro, Brazil. .,Cidade Industrial de Curitiba, Rua Professor Algacyr Munhoz Mader, 2135-2261, Curitiba, PR, 81310-020, Brazil.
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