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Honorato L, Bonilla JJA, Valdez AF, Frases S, Araújo GRDS, Sabino ALRDN, da Silva NM, Ribeiro L, Ferreira MDS, Kornetz J, Rodrigues ML, Cunningham I, Gow NAR, Gacser A, Guimarães AJ, Dutra FF, Nimrichter L. Toll-like receptor 4 (TLR4) is the major pattern recognition receptor triggering the protective effect of a Candida albicans extracellular vesicle-based vaccine prototype in murine systemic candidiasis. mSphere 2024:e0046724. [PMID: 39037263 DOI: 10.1128/msphere.00467-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2024] [Accepted: 06/26/2024] [Indexed: 07/23/2024] Open
Abstract
Systemic candidiasis remains a significant public health concern worldwide, with high mortality rates despite available antifungal drugs. Drug-resistant strains add to the urgency for alternative therapies. In this context, vaccination has reemerged as a prominent immune-based strategy. Extracellular vesicles (EVs), nanosized lipid bilayer particles, carry a diverse array of native fungal antigens, including proteins, nucleic acids, lipids, and glycans. Previous studies from our laboratory demonstrated that Candida albicans EVs triggered the innate immune response, activating bone marrow-derived dendritic cells (BMDCs) and potentially acting as a bridge between innate and adaptive immunity. Vaccination with C. albicans EVs induced the production of specific antibodies, modulated cytokine production, and provided protection in immunosuppressed mice infected with lethal C. albicans inoculum. To elucidate the mechanisms underlying EV-induced immune activation, our study investigated pathogen-associated molecular patterns (PAMPs) and pattern recognition receptors (PRRs) involved in EVs-phagocyte engagement. EVs from wild-type and mutant C. albicans strains with truncated mannoproteins were compared for their ability to stimulate BMDCs. Our findings revealed that EV decoration with O- and N-linked mannans and the presence of β-1,3-glucans and chitin oligomers may modulate the activation of specific PRRs, in particular Toll-like receptor 4 (TLR4) and dectin-1. The protective effect of vaccination with wild-type EVs was found to be dependent on TLR4. These results suggest that fungal EVs can be harnessed in vaccine formulations to selectively activate PRRs in phagocytes, offering potential avenues for combating or preventing candidiasis.IMPORTANCESystemic candidiasis is a serious global health concern with high mortality rates and growing drug resistance. Vaccination offers a promising solution. A unique approach involves using tiny lipid-coated particles called extracellular vesicles (EVs), which carry various fungal components. Previous studies found that Candida albicans EVs activate the immune response and may bridge the gap between innate and adaptive immunity. To understand this better, we investigated how these EVs activate immune cells. We demonstrated that specific components on EV surfaces, such as mannans and glucans, interact with receptors on immune cells, including Toll-like receptor 4 (TLR4) and dectin-1. Moreover, vaccinating with these EVs led to strong immune responses and full protection in mice infected with Candida. This work shows how harnessing fungal EVs might lead to effective vaccines against candidiasis.
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Affiliation(s)
- Leandro Honorato
- Laboratório de Glicobiologia de Eucariotos, Departamento de Microbiologia Geral, Instituto de Microbiologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Jhon J Artunduaga Bonilla
- Laboratório de Glicobiologia de Eucariotos, Departamento de Microbiologia Geral, Instituto de Microbiologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Alessandro F Valdez
- Laboratório de Glicobiologia de Eucariotos, Departamento de Microbiologia Geral, Instituto de Microbiologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Susana Frases
- Laboratório de Biofísica de Fungos, Instituto de Biofísica Carlos Chagas Filhos (IBCCF), Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- Rede Micologia, RJ, FAPERJ, Rio de Janeiro, Brazil
| | - Glauber Ribeiro de Sousa Araújo
- Laboratório de Biofísica de Fungos, Instituto de Biofísica Carlos Chagas Filhos (IBCCF), Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | | | - Natalia Martins da Silva
- Laboratório de Glicobiologia de Eucariotos, Departamento de Microbiologia Geral, Instituto de Microbiologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Larissa Ribeiro
- Laboratório de Glicobiologia de Eucariotos, Departamento de Microbiologia Geral, Instituto de Microbiologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Marina da Silva Ferreira
- Laboratório de Bioquímica e Imunologia das Micoses, Departamento de Microbiologia e Parasitologia, Instituto Biomédico, Universidade Federal Fluminense, Niterói, Rio de Janeiro, Brazil
| | - Julio Kornetz
- Laboratório de Glicobiologia de Eucariotos, Departamento de Microbiologia Geral, Instituto de Microbiologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Marcio L Rodrigues
- Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- Instituto Carlos Chagas (ICC), Fundação Oswaldo Cruz (FIOCRUZ), Curitiba, Brazil
| | - Iain Cunningham
- Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Neil A R Gow
- MRC Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | - Attila Gacser
- HCEMM-USZ Fungal Pathogens Research Group, Department of Microbiology, Faculty of Science and Informatics, University of Szeged, Szeged, Hungary
| | - Allan J Guimarães
- Rede Micologia, RJ, FAPERJ, Rio de Janeiro, Brazil
- MRC Centre for Medical Mycology, University of Exeter, Exeter, United Kingdom
| | - Fabianno F Dutra
- Rede Micologia, RJ, FAPERJ, Rio de Janeiro, Brazil
- Laboratório de Inflamação e Imunidade, Departamento de Imunologia, Instituto de Microbiologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Leonardo Nimrichter
- Laboratório de Glicobiologia de Eucariotos, Departamento de Microbiologia Geral, Instituto de Microbiologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
- Rede Micologia, RJ, FAPERJ, Rio de Janeiro, Brazil
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Hernández-Chávez MJ, Martínez-Duncker I, Clavijo-Giraldo DM, López-Ramirez LA, Mora-Montes HM. Candida tropicalis PMT2 Is a Dispensable Gene for Viability but Required for Proper Interaction with the Host. J Fungi (Basel) 2024; 10:502. [PMID: 39057387 PMCID: PMC11277967 DOI: 10.3390/jof10070502] [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: 07/01/2024] [Revised: 07/17/2024] [Accepted: 07/18/2024] [Indexed: 07/28/2024] Open
Abstract
Candidemia is an opportunistic mycosis with high morbidity and mortality rates. Even though Candida albicans is the main causative agent, other Candida species, such as Candida tropicalis, are relevant etiological agents of candidiasis and candidemia. Compared with C. albicans, there is currently limited information about C. tropicalis' biological aspects, including those related to the cell wall and the interaction with the host. Currently, it is known that its cell wall contains O-linked mannans, and the contribution of these structures to cell fitness has previously been addressed using cells subjected to chemical treatments or in mutants where O-linked mannans and other wall components are affected. Here, we generated a C. tropicalis pmt2∆ null mutant, which was affected in the first step of the O-linked mannosylation pathway. The null mutant was viable, contrasting with C. albicans where this gene is essential. The phenotypical characterization showed that O-linked mannans were required for filamentation; proper cell wall integrity and organization; biofilm formation; protein secretion; and adhesion to extracellular matrix components, in particular to fibronectin; and type I and type II collagen. When interacting with human innate immune cells, it was found that this cell wall structure is dispensable for cytokine production, but mutant cells were more phagocytosed by monocyte-derived macrophages. Furthermore, the null mutant cells showed virulence attenuation in Galleria mellonella larvae. Thus, O-linked mannans are minor components of the cell wall that are involved in different aspects of C. tropicalis' biology.
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Affiliation(s)
- Marco J. Hernández-Chávez
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Noria Alta s/n, col. Noria Alta, C.P., Guanajuato 36050, GTO, Mexico; (M.J.H.-C.); (D.M.C.-G.); (L.A.L.-R.)
| | - Iván Martínez-Duncker
- Laboratorio de Glicobiología Humana y Diagnóstico Molecular, Centro de Investigación en Dinámica Celular, Instituto de Investigación en Ciencias Básicas y Aplicadas, Universidad Autónoma del Estado de Morelos, Cuernavaca 62209, MOR, Mexico;
| | - Diana M. Clavijo-Giraldo
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Noria Alta s/n, col. Noria Alta, C.P., Guanajuato 36050, GTO, Mexico; (M.J.H.-C.); (D.M.C.-G.); (L.A.L.-R.)
| | - Luz A. López-Ramirez
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Noria Alta s/n, col. Noria Alta, C.P., Guanajuato 36050, GTO, Mexico; (M.J.H.-C.); (D.M.C.-G.); (L.A.L.-R.)
| | - Héctor M. Mora-Montes
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Noria Alta s/n, col. Noria Alta, C.P., Guanajuato 36050, GTO, Mexico; (M.J.H.-C.); (D.M.C.-G.); (L.A.L.-R.)
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3
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Silva PA, Souza AA, de Oliveira GM, Ramada MHS, Hernández NV, Mora-Montes HM, Bueno RV, Martins-de-Sa D, de Freitas SM, Felipe MSS, Barbosa JARG. An improved expression and purification protocol enables the structural characterization of Mnt1, an antifungal target from Candida albicans. Fungal Biol Biotechnol 2024; 11:5. [PMID: 38715132 PMCID: PMC11077754 DOI: 10.1186/s40694-024-00174-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2024] [Accepted: 04/22/2024] [Indexed: 05/12/2024] Open
Abstract
BACKGROUND Candida albicans is one of the most prevalent fungi causing infections in the world. Mnt1 is a mannosyltransferase that participates in both the cell wall biogenesis and biofilm growth of C. albicans. While the cell wall performs crucial functions in pathogenesis, biofilm growth is correlated with sequestration of drugs by the extracellular matrix. Therefore, antifungals targeting CaMnt1 can compromise fungal development and potentially also render Candida susceptible to drug therapy. Despite its importance, CaMnt1 has not yet been purified to high standards and its biophysical properties are lacking. RESULTS We describe a new protocol to obtain high yield of recombinant CaMnt1 in Komagataella phaffii using methanol induction. The purified protein's identity was confirmed by MALDI-TOF/TOF mass spectroscopy. The Far-UV circular dichroism (CD) spectra demonstrate that the secondary structure of CaMnt1 is compatible with a protein formed by α-helices and β-sheets at pH 7.0. The fluorescence spectroscopy results show that the tertiary structure of CaMnt1 is pH-dependent, with a greater intensity of fluorescence emission at pH 7.0. Using our molecular modeling protocol, we depict for the first time the ternary complex of CaMnt1 bound to its two substrates, which has enabled the identification of residues involved in substrate specificity and catalytic reaction. Our results corroborate the hypothesis that Tyr209 stabilizes the formation of an oxocarbenium ion-like intermediate during nucleophilic attack of the acceptor sugar, opposing the double displacement mechanism proposed by other reports. CONCLUSIONS The methodology presented here can substantially improve the yield of recombinant CaMnt1 expressed in flask-grown yeasts. In addition, the structural characterization of the fungal mannosyltransferase presents novelties that can be exploited for new antifungal drug's development.
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Affiliation(s)
- Patrícia Alves Silva
- Laboratório de Biofísica Molecular, Departamento de Biologia Celular, Instituto de Ciências Biológicas, Universidade de Brasília, Brasília, 70910-900, Brazil
| | - Amanda Araújo Souza
- Laboratório de Biofísica Molecular, Departamento de Biologia Celular, Instituto de Ciências Biológicas, Universidade de Brasília, Brasília, 70910-900, Brazil
| | - Gideane Mendes de Oliveira
- Laboratório de Biofísica Molecular, Departamento de Biologia Celular, Instituto de Ciências Biológicas, Universidade de Brasília, Brasília, 70910-900, Brazil
| | - Marcelo Henrique Soller Ramada
- Programa de Pós-graduação em Ciências Genômicas e Biotecnologia, Universidade Católica de Brasília, Brasília, 70790-160, Brazil
| | - Nahúm Valente Hernández
- Departmento de Biologia, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Guanajuato, 36050, Mexico
| | - Héctor Manuel Mora-Montes
- Departmento de Biologia, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Guanajuato, 36050, Mexico
| | - Renata Vieira Bueno
- Laboratório de Biofísica Molecular, Departamento de Biologia Celular, Instituto de Ciências Biológicas, Universidade de Brasília, Brasília, 70910-900, Brazil
| | - Diogo Martins-de-Sa
- Laboratório de Biofísica Molecular, Departamento de Biologia Celular, Instituto de Ciências Biológicas, Universidade de Brasília, Brasília, 70910-900, Brazil
- Genesilico Biotech, Brasília, DF, Brazil
| | - Sonia Maria de Freitas
- Laboratório de Biofísica Molecular, Departamento de Biologia Celular, Instituto de Ciências Biológicas, Universidade de Brasília, Brasília, 70910-900, Brazil
| | - Maria Sueli Soares Felipe
- Programa de Pós-graduação em Ciências Genômicas e Biotecnologia, Universidade Católica de Brasília, Brasília, 70790-160, Brazil
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Hang S, Lu H, Jiang Y. Marine-Derived Metabolites Act as Promising Antifungal Agents. Mar Drugs 2024; 22:180. [PMID: 38667797 PMCID: PMC11051449 DOI: 10.3390/md22040180] [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: 03/20/2024] [Revised: 04/11/2024] [Accepted: 04/13/2024] [Indexed: 04/28/2024] Open
Abstract
The incidence of invasive fungal diseases (IFDs) is on the rise globally, particularly among immunocompromised patients, leading to significant morbidity and mortality. Current clinical antifungal agents, such as polyenes, azoles, and echinocandins, face increasing resistance from pathogenic fungi. Therefore, there is a pressing need for the development of novel antifungal drugs. Marine-derived secondary metabolites represent valuable resources that are characterized by varied chemical structures and pharmacological activities. While numerous compounds exhibiting promising antifungal activity have been identified, a comprehensive review elucidating their specific underlying mechanisms remains lacking. In this review, we have compiled a summary of antifungal compounds derived from marine organisms, highlighting their diverse mechanisms of action targeting various fungal cellular components, including the cell wall, cell membrane, mitochondria, chromosomes, drug efflux pumps, and several biological processes, including vesicular trafficking and the growth of hyphae and biofilms. This review is helpful for the subsequent development of antifungal drugs due to its summary of the antifungal mechanisms of secondary metabolites from marine organisms.
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Affiliation(s)
| | - Hui Lu
- Department of Pharmacy, Shanghai Tenth People’s Hospital, School of Medicine, Tongji University, 200092 Shanghai, China
| | - Yuanying Jiang
- Department of Pharmacy, Shanghai Tenth People’s Hospital, School of Medicine, Tongji University, 200092 Shanghai, China
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5
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Oh MJ, Yoon S, Babeer A, Liu Y, Ren Z, Xiang Z, Miao Y, Cormode DP, Chen C, Steager E, Koo H. Nanozyme-Based Robotics Approach for Targeting Fungal Infection. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2024; 36:e2300320. [PMID: 37141008 PMCID: PMC10624647 DOI: 10.1002/adma.202300320] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/11/2023] [Revised: 04/29/2023] [Indexed: 05/05/2023]
Abstract
Fungal pathogens have been designated by the World Health Organization as microbial threats of the highest priority for global health. It remains a major challenge to improve antifungal efficacy at the site of infection while avoiding off-target effects, fungal spreading, and drug tolerance. Here, a nanozyme-based microrobotic platform is developed that directs localized catalysis to the infection site with microscale precision to achieve targeted and rapid fungal killing. Using electromagnetic field frequency modulation and fine-scale spatiotemporal control, structured iron oxide nanozyme assemblies are formed that display tunable dynamic shape transformation and catalysis activation. The catalytic activity varies depending on the motion, velocity, and shape providing controllable reactive oxygen species (ROS) generation. Unexpectedly, nanozyme assemblies bind avidly to fungal (Candida albicans) surfaces to enable concentrated accumulation and targeted ROS-mediated killing in situ. By exploiting these tunable properties and selective binding to fungi, localized antifungal activity is achieved using in vivo-like cell spheroid and animal tissue infection models. Structured nanozyme assemblies are directed to Candida-infected sites using programmable algorithms to perform precisely guided spatial targeting and on-site catalysis resulting in fungal eradication within 10 min. This nanozyme-based microrobotics approach provides a uniquely effective and targeted therapeutic modality for pathogen elimination at the infection site.
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Affiliation(s)
- Min Jun Oh
- Biofilm Research Laboratories, Levy Center for Oral Health, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Chemical and Biomolecular Engineering, School of Engineering & Applied Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Orthodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Seokyoung Yoon
- Biofilm Research Laboratories, Levy Center for Oral Health, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Pennsylvania, Philadelphia, PA 19104, USA
| | - Alaa Babeer
- Biofilm Research Laboratories, Levy Center for Oral Health, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Endodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Oral Biology, King Abdulaziz University, Jeddah 21589, KSA
| | - Yuan Liu
- Biofilm Research Laboratories, Levy Center for Oral Health, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Preventive & Restorative Sciences, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Zhi Ren
- Biofilm Research Laboratories, Levy Center for Oral Health, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Center for Innovation & Precision Dentistry, School of Dental Medicine and School of Engineering & Applied Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Orthodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Zhenting Xiang
- Biofilm Research Laboratories, Levy Center for Oral Health, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Orthodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Yilan Miao
- Biofilm Research Laboratories, Levy Center for Oral Health, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Orthodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - David P. Cormode
- Department of Radiology, Perelman School of Medicine, University of Pennsylvania, Pennsylvania, Philadelphia, PA 19104, USA
- Department of Bioengineering, School of Engineering & Applied Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Chider Chen
- Department of Oral and Maxillofacial Surgery and Pharmacology, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - Edward Steager
- Biofilm Research Laboratories, Levy Center for Oral Health, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Center for Innovation & Precision Dentistry, School of Dental Medicine and School of Engineering & Applied Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA
- GRASP Laboratory, School of Engineering & Applied Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA
| | - Hyun Koo
- Biofilm Research Laboratories, Levy Center for Oral Health, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Department of Orthodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
- Center for Innovation & Precision Dentistry, School of Dental Medicine and School of Engineering & Applied Sciences, University of Pennsylvania, Philadelphia, PA 19104, USA
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Kalita B, Roy A, Jayaprakash A, Arunachalam A, P.T.V L. Identification of lncRNA and weighted gene coexpression network analysis of germinating Rhizopus delemar causing mucormycosis. Mycology 2024; 14:344-357. [PMID: 38187880 PMCID: PMC10769135 DOI: 10.1080/21501203.2023.2265414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Accepted: 09/27/2023] [Indexed: 01/09/2024] Open
Abstract
Rhizopus delemar, an opportunistic fungal pathogen, causes a highly fatal disease, mucormycosis. Spore germination is a crucial mechanism for disease pathogenesis. Thus, exploring the molecular mechanisms of fungal germination would underpin our knowledge of such transformation and, in turn, help control mucormycosis. To gain insight into the developmental process particularly associated with cell wall modification and synthesis, weighted gene co-expression network analysis (WGCNA) was performed including both coding and non-coding transcripts identified in the current study, to find out the module of interest in the germination stages. The module-trait relationship identified a particular module to have a high correlation only at the resting phase and further analysis revealed the module to be enriched for protein phosphorylation, carbohydrate metabolic process, and cellular response to stimulus. Moreover, co-expression network analysis of highly connected nodes revealed cell wall modifying enzymes, especially those involved in mannosylation, chitin-glucan crosslinking, and polygalacturonase activities co-expressing and interacting with the novel lncRNAs among which some of them predicted to be endogenous target mimic (eTM) lncRNAs. Hence, the present study provides an insight into the onset of spore germination and the information on the novel non-coding transcripts with key cell wall-related enzymes as potential targets against mucormycosis.
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Affiliation(s)
- Barsha Kalita
- Department of Bioinformatics, Pondicherry University, Puducherry, India
| | - Abhijeet Roy
- Department of Bioinformatics, Pondicherry University, Puducherry, India
| | | | | | - Lakshmi P.T.V
- Department of Bioinformatics, Pondicherry University, Puducherry, India
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Pinho SS, Alves I, Gaifem J, Rabinovich GA. Immune regulatory networks coordinated by glycans and glycan-binding proteins in autoimmunity and infection. Cell Mol Immunol 2023; 20:1101-1113. [PMID: 37582971 PMCID: PMC10541879 DOI: 10.1038/s41423-023-01074-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2023] [Accepted: 07/26/2023] [Indexed: 08/17/2023] Open
Abstract
The immune system is coordinated by an intricate network of stimulatory and inhibitory circuits that regulate host responses against endogenous and exogenous insults. Disruption of these safeguard and homeostatic mechanisms can lead to unpredictable inflammatory and autoimmune responses, whereas deficiency of immune stimulatory pathways may orchestrate immunosuppressive programs that contribute to perpetuate chronic infections, but also influence cancer development and progression. Glycans have emerged as essential components of homeostatic circuits, acting as fine-tuners of immunological responses and potential molecular targets for manipulation of immune tolerance and activation in a wide range of pathologic settings. Cell surface glycans, present in cells, tissues and the extracellular matrix, have been proposed to serve as "self-associated molecular patterns" that store structurally relevant biological data. The responsibility of deciphering this information relies on different families of glycan-binding proteins (including galectins, siglecs and C-type lectins) which, upon recognition of specific carbohydrate structures, can recalibrate the magnitude, nature and fate of immune responses. This process is tightly regulated by the diversity of glycan structures and the establishment of multivalent interactions on cell surface receptors and the extracellular matrix. Here we review the spatiotemporal regulation of selected glycan-modifying processes including mannosylation, complex N-glycan branching, core 2 O-glycan elongation, LacNAc extension, as well as terminal sialylation and fucosylation. Moreover, we illustrate examples that highlight the contribution of these processes to the control of immune responses and their integration with canonical tolerogenic pathways. Finally, we discuss the power of glycans and glycan-binding proteins as a source of immunomodulatory signals that could be leveraged for the treatment of autoimmune inflammation and chronic infection.
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Affiliation(s)
- Salomé S Pinho
- i3S - Institute for Research and Innovation in Health, University of Porto, 4200-135, Porto, Portugal.
- ICBAS-School of Medicine and Biomedical Sciences, University of Porto, 4050-313, Porto, Portugal.
- Faculty of Medicine, University of Porto, 4200-319, Porto, Portugal.
| | - Inês Alves
- i3S - Institute for Research and Innovation in Health, University of Porto, 4200-135, Porto, Portugal
| | - Joana Gaifem
- i3S - Institute for Research and Innovation in Health, University of Porto, 4200-135, Porto, Portugal
| | - Gabriel A Rabinovich
- Laboratorio de Glicomedicina, Instituto de Biología y Medicina Experimental (IBYME), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), C1428, Ciudad de Buenos Aires, Argentina.
- Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, C1428, Ciudad de Buenos Aires, Argentina.
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8
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Wang T, Liu J, Luo Y, Yu B, Kong X, Zheng P, Huang Z, Mao X, Yu J, Luo J, Yan H, He J. Combined effects of host genetics and diet on porcine intestinal fungi and their pathogenic genes. Front Microbiol 2023; 14:1192288. [PMID: 37822749 PMCID: PMC10563851 DOI: 10.3389/fmicb.2023.1192288] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Accepted: 09/11/2023] [Indexed: 10/13/2023] Open
Abstract
As research on gut microbes progresses, it becomes increasingly clear that a small family of microbiota--fungi, plays a crucial role in animal health. However, little is known about the fungal composition in the pig intestine, especially after a dietary fiber diet and hybrid genetics, and the changes in host pathogenicity-associated genes they carry. The purpose of this study is to investigate the effects of diet and genetics on the diversity and structure of porcine intestinal fungi and to describe, for the first time, the host pathogenicity-related genes carried by porcine intestinal fungi. Samples of colonic contents were collected for metagenomic analysis using a 3 × 2 parsing design, where three pig breeds (Taoyuan, Duroc, and crossbred Xiangcun) were fed high or low fiber diets (n = 10). In all samples, we identified a total of 281 identifiable fungal genera, with Ascomycota and Microsporidia being the most abundant fungi. Compared to Duroc pigs, Taoyuan and Xiangcun pigs had higher fungal richness. Interestingly, the fiber diet significantly reduced the abundance of the pathogenic fungus Mucor and significantly increased the abundance of the fiber digestion-associated fungus Neocallimastix. Pathogenic fungi exert their pathogenicity through the genes they carry that are associated with host pathogenicity. Therefore, we obtained 839 pathogenicity genes carried by the spectrum of fungi in the pig intestine by comparing the PHI-base database. Our results showed that fungi in the colon of Taoyuan pigs carried the highest abundance of different classes of host pathogenicity-related genes, and the lowest in Duroc pigs. Specifically, Taoyuan pigs carried high abundance of animal pathogenicity-related genes (CaTUP1, CPAR2_106400, CaCDC35, Tfp1, CaMNT2), and CaTUP1 was the key gene for Candida pathogenicity. The intestinal fungal composition of crossbred Xiangcun pigs and the abundance of host pathogenicity-associated genes they carried exhibited a mixture of characteristics of Taoyuan and Duroc pigs. In conclusion, our results provide the first comprehensive report on the effects of dietary fiber and genetics on the composition of intestinal fungi and the host-associated pathogenicity genes they carry in pigs. These findings provide a reference for subsequent pig breeding and development of anti-pathogenic fungal drugs.
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Affiliation(s)
- Tao Wang
- Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease-resistant Nutrition, Chengdu, China
| | - Jiahao Liu
- Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease-resistant Nutrition, Chengdu, China
| | - Yuheng Luo
- Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease-resistant Nutrition, Chengdu, China
| | - Bing Yu
- Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease-resistant Nutrition, Chengdu, China
| | - Xiangfeng Kong
- Institute of Subtropical Agriculture, Chinese Academy of Sciences, Changsha, China
| | - Ping Zheng
- Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease-resistant Nutrition, Chengdu, China
| | - Zhiqing Huang
- Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease-resistant Nutrition, Chengdu, China
| | - Xiangbing Mao
- Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease-resistant Nutrition, Chengdu, China
| | - Jie Yu
- Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease-resistant Nutrition, Chengdu, China
| | - Junqiu Luo
- Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease-resistant Nutrition, Chengdu, China
| | - Hui Yan
- Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease-resistant Nutrition, Chengdu, China
| | - Jun He
- Institute of Animal Nutrition, Sichuan Agricultural University, Chengdu, China
- Key Laboratory of Animal Disease-resistant Nutrition, Chengdu, China
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9
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Ocaña-Ortega A, Pérez-Flores G, Torres-Tirado D, Pérez-García LA. O-Linked Glycans of Candida albicans Interact with Specific GPCRs in the Coronary Endothelium and Inhibit the Cardiac Response to Agonists. J Fungi (Basel) 2023; 9:jof9020141. [PMID: 36836256 PMCID: PMC9960525 DOI: 10.3390/jof9020141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 01/17/2023] [Accepted: 01/18/2023] [Indexed: 01/22/2023] Open
Abstract
Candida albicans is an opportunistic fungal pathogen that may cause invasive infections in immunocompromised patients, disseminating through the bloodstream to other organs. In the heart, the initial step prior to invasion is the adhesion of the fungus to endothelial cells. Being the fungal cell wall's outermost structure and the first to come in contact with host cells, it greatly modulates the interplay that later will derive in the colonization of the host tissue. In this work, we studied the functional contribution of N-linked and O-linked mannans of the cell wall of C. albicans to the interaction with the coronary endothelium. An isolated rat heart model was used to assess cardiac parameters related to vascular and inotropic effects in response to phenylephrine (Phe), acetylcholine (aCh) and angiotensin II (Ang II) when treatments consisting of: (1) live and heat-killed (HK) C. albicans wild-type yeasts; (2) live C. albicans pmr1Δ yeasts (displaying shorter N-linked and O-linked mannans); (3) live C. albicans without N-linked and O-linked mannans; and (4) isolated N-linked and O-linked mannans were administered to the heart. Our results showed that C. albicans WT alters heart coronary perfusion pressure (vascular effect) and left ventricular pressure (inotropic effect) parameters in response to Phe and Ang II but not aCh, and these effects can be reversed by mannose. Similar results were observed when isolated cell walls, live C. albicans without N-linked mannans or isolated O-linked mannans were perfused into the heart. In contrast, C. albicans HK, C. albicans pmr1Δ, C. albicans without O-linked mannans or isolated N-linked mannans were not able to alter the CPP and LVP in response to the same agonists. Taken together, our data suggest that C. albicans interaction occurs with specific receptors on coronary endothelium and that O-linked mannan contributes to a greater extent to this interaction. Further studies are necessary to elucidate why specific receptors preferentially interact with this fungal cell wall structure.
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10
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Extension of O-Linked Mannosylation in the Golgi Apparatus Is Critical for Cell Wall Integrity Signaling and Interaction with Host Cells in Cryptococcus neoformans Pathogenesis. mBio 2022; 13:e0211222. [PMID: 36409123 PMCID: PMC9765558 DOI: 10.1128/mbio.02112-22] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The human-pathogenic yeast Cryptococcus neoformans assembles two types of O-linked glycans on its proteins. In this study, we identified and functionally characterized the C. neoformans CAP6 gene, encoding an α1,3-mannosyltransferase responsible for the second mannose addition to minor O-glycans containing xylose in the Golgi apparatus. Two cell surface sensor proteins, Wml1 (WSC/Mid2-like) and Wml2, were found to be independent substrates of Cap6-mediated minor or Ktr3-mediated major O-mannosylation, respectively. The double deletion of KTR3 and CAP6 (ktr3Δ cap6Δ) completely blocked the mannose addition at the second position of O-glycans, resulting in the accumulation of proteins with O-glycans carrying only a single mannose. Tunicamycin (TM)-induced phosphorylation of the Mpk1 mitogen-activated protein kinase (MAPK) was greatly decreased in both ktr3Δ cap6Δ and wml1Δ wml2Δ strains. Transcriptome profiling of the ktr3Δ cap6Δ strain upon TM treatment revealed decreased expression of genes involved in the Mpk1-dependent cell wall integrity (CWI) pathway. Consistent with its defective growth under several stress conditions, the ktr3Δ cap6Δ strain was avirulent in a mouse model of cryptococcosis. Associated with this virulence defect, the ktr3Δ cap6Δ strain showed decreased adhesion to lung epithelial cells, decreased proliferation within macrophages, and reduced transcytosis of the blood-brain barrier (BBB). Notably, the ktr3Δ cap6Δ strain showed reduced induction of the host immune response and defective trafficking of ergosterol, an immunoreactive fungal molecule. In conclusion, O-glycan extension in the Golgi apparatus plays critical roles in various pathobiological processes, such as CWI signaling and stress resistance and interaction with host cells in C. neoformans. IMPORTANCE Cryptococcus neoformans assembles two types of O-linked glycans on its surface proteins, the more abundant major O-glycans that do not contain xylose residues and minor O-glycans containing xylose. Here, we demonstrate the role of the Cap6 α1,3-mannosyltransferase in the synthesis of minor O-glycans. Previously proposed to be involved in capsule biosynthesis, Cap6 works with the related Ktr3 α1,2-mannosyltransferase to synthesize O-glycans on their target proteins. We also identified two novel C. neoformans stress sensors that require Ktr3- and Cap6-mediated posttranslational modification for full function. Accordingly, the ktr3Δ cap6Δ double O-glycan mutant strain displays defects in stress signaling pathways, CWI, and ergosterol trafficking. Furthermore, the ktr3Δ cap6Δ strain is completely avirulent in a mouse infection model. Together, these results demonstrate critical roles for O-glycosylation in fungal pathogenesis. As there are no human homologs for Cap6 or Ktr3, these fungus-specific mannosyltransferases are novel targets for antifungal therapy.
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11
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Mendoza-Reyes DF, Gómez-Gaviria M, Mora-Montes HM. Candida lusitaniae: Biology, Pathogenicity, Virulence Factors, Diagnosis, and Treatment. Infect Drug Resist 2022; 15:5121-5135. [PMID: 36068831 PMCID: PMC9441179 DOI: 10.2147/idr.s383785] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 08/25/2022] [Indexed: 12/30/2022] Open
Abstract
The incidence of fungal infections is increasing at an alarming rate and has posed a great challenge for science in recent years. The rise in these infections has been related to the increase in immunocompromised patients and the resistance of different species to antifungal drugs. Infections caused by the different Candida species, especially Candida albicans, are one of the most common mycoses in humans, and the etiological agents are considered opportunistic pathogens associated with high mortality rates when disseminated infections occur. Candida lusitaniae is considered an emerging opportunistic pathogen that most frequently affects immunocompromised patients with some comorbidity. Although it is a low-frequency pathogen, and the mortality rate of C. lusitaniae-caused candidemia does not exceed 5%, some isolates are known to be resistant to antifungals such as amphotericin B, 5-fluorocytosine, and fluconazole. In this paper, a detailed review of the current literature on this organism and its different aspects, such as its biology, possible virulence factors, pathogen-host interaction, diagnosis, and treatment of infection, is provided. Of particular interest, through Blastp analysis we predicted possible virulence factors in this species.
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Affiliation(s)
- Diana F Mendoza-Reyes
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Guanajuato, Gto, C.P. 36050, México
| | - Manuela Gómez-Gaviria
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Guanajuato, Gto, C.P. 36050, México
- Correspondence: Manuela Gómez-Gaviria; Héctor M Mora-Montes, Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Noria Alta s/n, col. Noria Alta, Guanajuato, Gto, C.P. 36050, México, Tel +52 473-7320006 Ext. 8193, Fax +52 473-7320006 Ext. 8153, Email ;
| | - Héctor M Mora-Montes
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Guanajuato, Gto, C.P. 36050, México
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12
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Shao TY, Kakade P, Witchley JN, Frazer C, Murray KL, Ene IV, Haslam DB, Hagan T, Noble SM, Bennett RJ, Way SS. Candida albicans oscillating UME6 expression during intestinal colonization primes systemic Th17 protective immunity. Cell Rep 2022; 39:110837. [PMID: 35584674 PMCID: PMC9196946 DOI: 10.1016/j.celrep.2022.110837] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 03/23/2022] [Accepted: 04/27/2022] [Indexed: 01/09/2023] Open
Abstract
Systemic immunity is stringently regulated by commensal intestinal microbes, including the pathobiont Candida albicans. This fungus utilizes various transcriptional and morphological programs for host adaptation, but how this heterogeneity affects immunogenicity remains uncertain. We show that UME6, a transcriptional regulator of filamentation, is essential for intestinal C. albicans-primed systemic Th17 immunity. UME6 deletion and constitutive overexpression strains are non-immunogenic during commensal colonization, whereas immunogenicity is restored by C. albicans undergoing oscillating UME6 expression linked with β-glucan and mannan production. In turn, intestinal reconstitution with these fungal cell wall components restores protective Th17 immunity to mice colonized with UME6-locked variants. These fungal cell wall ligands and commensal C. albicans stimulate Th17 immunity through multiple host pattern recognition receptors, including Toll-like receptor 2 (TLR2), TLR4, Dectin-1, and Dectin-2, which work synergistically for colonization-induced protection. Thus, dynamic gene expression fluctuations by C. albicans during symbiotic colonization are essential for priming host immunity against disseminated infection.
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Affiliation(s)
- Tzu-Yu Shao
- Division of Infectious Diseases, Center for Inflammation and Tolerance, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA; Immunobiology Graduate Program, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA
| | - Pallavi Kakade
- Molecular Microbiology and Immunology Department, Brown University, Providence, RI 02912, USA
| | - Jessica N Witchley
- Department of Microbiology and Immunology, University of California, San Francisco School of Medicine, San Francisco, CA 94143, USA
| | - Corey Frazer
- Molecular Microbiology and Immunology Department, Brown University, Providence, RI 02912, USA
| | - Kathryn L Murray
- Division of Infectious Diseases, Center for Inflammation and Tolerance, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA
| | - Iuliana V Ene
- Fungal Heterogeneity Lab, Institut Pasteur, Université Paris Cité, 75015 Paris, France
| | - David B Haslam
- Division of Infectious Diseases, Center for Inflammation and Tolerance, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA
| | - Thomas Hagan
- Division of Infectious Diseases, Center for Inflammation and Tolerance, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA
| | - Suzanne M Noble
- Department of Microbiology and Immunology, University of California, San Francisco School of Medicine, San Francisco, CA 94143, USA
| | - Richard J Bennett
- Molecular Microbiology and Immunology Department, Brown University, Providence, RI 02912, USA
| | - Sing Sing Way
- Division of Infectious Diseases, Center for Inflammation and Tolerance, Cincinnati Children's Hospital Medical Center, University of Cincinnati College of Medicine, Cincinnati, OH 45229, USA.
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13
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Dean N, Jones R, DaSilva J, Chionchio G, Ng H. The Mnn10/Anp1-dependent N-linked outer chain glycan is dispensable for Candida albicans cell wall integrity. Genetics 2022; 221:6554200. [PMID: 35333306 PMCID: PMC9071539 DOI: 10.1093/genetics/iyac048] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 03/11/2022] [Indexed: 11/13/2022] Open
Abstract
Candida albicans cell wall glycoproteins, and in particular their mannose-rich glycans, are important for maintaining cellular integrity as well as host recognition, adhesion, and immunomodulation. The asparagine (N)-linked mannose outer chain of these glycoproteins is produced by Golgi mannosyltransferases (MTases). The outer chain is composed of a linear backbone of ∼50 α1,6-linked mannoses, which acts as a scaffold for addition of ∼150 or more mannoses in other linkages. Here, we describe the characterization of C. albicans OCH1, MNN9, VAN1, ANP1, MNN10, and MNN11, which encode the conserved Golgi MTases that sequentially catalyze the α1,6 mannose outer chain backbone. Candida albicans och1Δ/Δ, mnn9Δ/Δ, and van1Δ/Δ mutants block the earliest steps of backbone synthesis and like their Saccharomyces cerevisiae counterparts, have severe cell wall and growth phenotypes. Unexpectedly, and in stark contrast to S. cerevisiae, loss of Anp1, Mnn10, or Mnn11, which together synthesize most of the backbone, have no obvious deleterious phenotypes. These mutants were unaffected in cell morphology, growth, drug sensitivities, hyphal formation, and macrophage recognition. Analyses of secreted glycosylation reporters demonstrated that anp1Δ/Δ, mnn10Δ/Δ, and mnn11Δ/Δ strains accumulate glycoproteins with severely truncated N-glycan chains. This hypo-mannosylation did not elicit increased chitin deposition in the cell wall, which in other yeast and fungi is a key compensatory response to cell wall integrity breaches. Thus, C. albicans has evolved an alternate mechanism to adapt to cell wall weakness when N-linked mannan levels are reduced.
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Affiliation(s)
- Neta Dean
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY 11794-5215, USA
- Corresponding author: Department of Biochemistry and Cell Biology, Life Sciences Bldg Room 310, Stony Brook University, Stony Brook, NY 11794-5215, USA.
| | - Rachel Jones
- Department of Anesthesiology, Montefiore Medical Center, Albert Einstein College of Medicine, Bronx, NY 10467, USA
| | - Justin DaSilva
- Laboratory of Retrovirology, The Rockefeller University, New York, NY 10065, USA
| | - Gregory Chionchio
- Donald and Barbara Zucker School of Medicine, Hofstra/Northwell, Hempstead, NY 11549, USA
| | - Henry Ng
- Department of Physiology, University of California, San Francisco, CA 94143, USA
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14
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Alves I, Fernandes Â, Santos-Pereira B, Azevedo CM, Pinho SS. Glycans as a key factor in self and non-self discrimination: Impact on the breach of immune tolerance. FEBS Lett 2022; 596:1485-1502. [PMID: 35383918 DOI: 10.1002/1873-3468.14347] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 03/17/2022] [Accepted: 03/29/2022] [Indexed: 11/09/2022]
Abstract
Glycans are carbohydrates that are made by all organisms and covalently conjugated to other biomolecules. Glycans cover the surface of both human cells and pathogens and are fundamental to defining the identity of a cell or an organism, thereby contributing to discriminating self from non-self. As such, glycans are a class of "Self-Associated Molecular Patterns" that can fine-tune host inflammatory processes. In fact, glycans can be sensed and recognized by a variety of glycan-binding proteins (GBP) expressed by immune cells, such as galectins, siglecs and C-type lectins, which recognize changes in the cellular glycosylation, instructing both pro-inflammatory or anti-inflammatory responses. In this review, we introduce glycans as cell-identification structures, discussing how glycans modulate host-pathogen interactions and how they can fine-tune inflammatory processes associated with infection, inflammation and autoimmunity. Finally, from the clinical standpoint, we discuss how glycoscience research can benefit life sciences and clinical medicine by providing a source of valuable biomarkers and therapeutic targets for immunity.
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Affiliation(s)
- Inês Alves
- Institute for Research and Innovation in Health, University of Porto, Porto, Portugal.,Faculty of Medicine, University of Porto, Porto, Portugal
| | - Ângela Fernandes
- Institute for Research and Innovation in Health, University of Porto, Porto, Portugal
| | - Beatriz Santos-Pereira
- Institute for Research and Innovation in Health, University of Porto, Porto, Portugal.,Faculty of Medicine, University of Porto, Porto, Portugal
| | - Catarina M Azevedo
- Institute for Research and Innovation in Health, University of Porto, Porto, Portugal.,Institute of Biomedical Sciences Abel Salazar, University of Porto, Portugal
| | - Salomé S Pinho
- Institute for Research and Innovation in Health, University of Porto, Porto, Portugal.,Faculty of Medicine, University of Porto, Porto, Portugal.,Institute of Biomedical Sciences Abel Salazar, University of Porto, Portugal
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15
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Role of Protein Glycosylation in Interactions of Medically Relevant Fungi with the Host. J Fungi (Basel) 2021; 7:jof7100875. [PMID: 34682296 PMCID: PMC8541085 DOI: 10.3390/jof7100875] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Revised: 10/08/2021] [Accepted: 10/11/2021] [Indexed: 01/09/2023] Open
Abstract
Protein glycosylation is a highly conserved post-translational modification among organisms. It plays fundamental roles in many biological processes, ranging from protein trafficking and cell adhesion to host–pathogen interactions. According to the amino acid side chain atoms to which glycans are linked, protein glycosylation can be divided into two major categories: N-glycosylation and O-glycosylation. However, there are other types of modifications such as the addition of GPI to the C-terminal end of the protein. Besides the importance of glycoproteins in biological functions, they are a major component of the fungal cell wall and plasma membrane and contribute to pathogenicity, virulence, and recognition by the host immunity. Given that this structure is absent in host mammalian cells, it stands as an attractive target for developing selective compounds for the treatment of fungal infections. This review focuses on describing the relationship between protein glycosylation and the host–immune interaction in medically relevant fungal species.
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16
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Zhang X, Gu N, Zhou Y, Godana EA, Dhanasekaran S, Gu X, Zhao L, Zhang H. Transcriptome analysis reveals the mechanisms involved in the enhanced antagonistic efficacy of Rhodotorula mucilaginosa induced by chitosan. Lebensm Wiss Technol 2021. [DOI: 10.1016/j.lwt.2021.110992] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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17
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Tamez-Castrellón AK, Romeo O, García-Carnero LC, Lozoya-Pérez NE, Mora-Montes HM. Virulence Factors in Sporothrix schenckii, One of the Causative Agents of Sporotrichosis. Curr Protein Pept Sci 2021; 21:295-312. [PMID: 31589121 DOI: 10.2174/1389203720666191007103004] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 08/02/2019] [Accepted: 08/08/2019] [Indexed: 11/22/2022]
Abstract
Sporothrix schenckii is one of the etiological agents of sporotrichosis, a fungal infection distributed worldwide. Both, the causative organism and the disease have currently received limited attention by the medical mycology community, most likely because of the low mortality rates associated with it. Nonetheless, morbidity is high in endemic regions and the versatility of S. schenckii to cause zoonosis and sapronosis has attracted attention. Thus far, virulence factors associated with this organism are poorly described. Here, comparing the S. schenckii genome sequence with other medically relevant fungi, genes involved in morphological change, cell wall synthesis, immune evasion, thermotolerance, adhesion, biofilm formation, melanin production, nutrient uptake, response to stress, extracellular vesicle formation, and toxin production are predicted and discussed as putative virulence factors in S. schenckii.
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Affiliation(s)
- Alma K Tamez-Castrellón
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Noria Alta s/n, col. Noria Alta, C.P. 36050, Guanajuato, Gto., Mexico
| | - Orazio Romeo
- Department of Chemical, Biological, Pharmaceutical and Environmental Sciences, University of Messina, Messina, Italy
| | - Laura C García-Carnero
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Noria Alta s/n, col. Noria Alta, C.P. 36050, Guanajuato, Gto., Mexico
| | - Nancy E Lozoya-Pérez
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Noria Alta s/n, col. Noria Alta, C.P. 36050, Guanajuato, Gto., Mexico
| | - Héctor M Mora-Montes
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Noria Alta s/n, col. Noria Alta, C.P. 36050, Guanajuato, Gto., Mexico
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18
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Lenardon MD, Sood P, Dorfmueller HC, Brown AJ, Gow NA. Scalar nanostructure of the Candida albicans cell wall; a molecular, cellular and ultrastructural analysis and interpretation. Cell Surf 2020; 6:100047. [PMID: 33294751 PMCID: PMC7691183 DOI: 10.1016/j.tcsw.2020.100047] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2020] [Revised: 11/02/2020] [Accepted: 11/03/2020] [Indexed: 12/16/2022] Open
Abstract
Despite the importance of fungal cell walls as the principle determinant of fungal morphology and the defining element determining fungal interactions with other cells, few scalar models have been developed that reconcile chemical and microscopic attributes of its structure. The cell wall of the fungal pathogen Candida albicans is comprised of an amorphous inner skeletal layer of β(1,3)- and β(1,6)-glucan and chitin and an outer fibrillar layer thought to be dominated by highly mannosylated cell wall proteins. The architecture of these two layers can be resolved at the electron microscopy level, but the visualised structure of the wall has not yet been defined precisely in chemical terms. We have therefore examined the precise structure, location and molecular sizes of the cell wall components using transmission electron microscopy and tomography and tested predictions of the cell wall models using mutants and agents that perturb the normal cell wall structure. We demonstrate that the fibrils are comprised of a frond of N-linked outer chain mannans linked to a basal layer of GPI-proteins concentrated in the mid-wall region and that the non-elastic chitin microfibrils are cantilevered with sufficient lengths of non-fibrillar chitin and/or β-glucan to enable the chitin-glucan cage to flex, e.g. during morphogenesis and osmotic swelling. We present the first three-dimensional nano-scalar model of the C. albicans cell wall which can be used to test hypotheses relating to the structure-function relationships that underpin the pathobiology of this fungal pathogen.
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Key Words
- 2D, two dimensions
- 2°, secondary
- 3D, three dimensions
- 3°, tertiary
- 6xHis, hexahistidine tag
- AFM, atomic force microscopy
- BSA, bovine serum albumin
- CWPs, cell wall proteins
- Cell wall proteins
- ChBD, chitin binding domain
- Chitin
- EndoH, endoglycosidase H
- Fc-dectin-1, soluble chimeric form of dectin-1
- Fungal cell wall ultrastructure
- GPI, glycosylphosphatidylinositol
- HPF/FS, high pressure freezing/freeze substitution
- HuCκ, human kappa light chain
- N-mannan
- NMR, nuclear magnetic resonance
- OD600, optical density at 600 nm
- PAMPs, pathogen associated molecular patterns
- PBS, phosphate buffered saline
- PRRs, pattern recognition receptors
- SEM, scanning electron microscopy
- TEM, transmission electron microscopy
- WGA, wheat germ agglutinin
- rpm, revolutions per minute
- scAb, single chain antibody
- β-glucan
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Affiliation(s)
- Megan D. Lenardon
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, UK
| | - Prashant Sood
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, UK
| | - Helge C. Dorfmueller
- Molecular Microbiology, School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, UK
| | - Alistair J.P. Brown
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, UK
| | - Neil A.R. Gow
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen AB25 2ZD, Scotland, UK
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19
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Abstract
Invasive fungal infections in humans are generally associated with high mortality, making the choice of antifungal drug crucial for the outcome of the patient. The limited spectrum of antifungals available and the development of drug resistance represent the main concerns for the current antifungal treatments, requiring alternative strategies. Antimicrobial peptides (AMPs), expressed in several organisms and used as first-line defenses against microbial infections, have emerged as potential candidates for developing new antifungal therapies, characterized by negligible host toxicity and low resistance rates. Most of the current literature focuses on peptides with antibacterial activity, but there are fewer studies of their antifungal properties. This review focuses on AMPs with antifungal effects, including their in vitro and in vivo activities, with the biological repercussions on the fungal cells, when known. The classification of the peptides is based on their mode of action: although the majority of AMPs exert their activity through the interaction with membranes, other mechanisms have been identified, including cell wall inhibition and nucleic acid binding. In addition, antifungal compounds with unknown modes of action are also described. The elucidation of such mechanisms can be useful to identify novel drug targets and, possibly, to serve as the templates for the synthesis of new antimicrobial compounds with increased activity and reduced host toxicity.
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20
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Tanaka H, Yanai C, Miura NN, Ishibashi KI, Yamanaka D, Ohnishi H, Ohno N, Adachi Y. Coronary Vasculitis Induced in Mice by Cell Wall Mannoprotein Fractions of Clinically Isolated Candida Species. Med Mycol J 2020; 61:33-48. [PMID: 32863327 DOI: 10.3314/mmj.20-00008] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Kawasaki disease (KD) is an inflammatory disease that was identified by Professor Tomisaku Kawasaki in 1961. Candida albicans-derived substances (CADS) such as the hot water extract of C. albicans and Candida water-soluble fractions (CAWS) induce coronary vasculitis similar to KD in mice. An increasing proportion of deep-seated candidiasis cases are caused by non-albicans Candida and are often resistant to antifungal drugs. We herein investigated whether the mannoprotein fractions (MN fractions) of clinically isolated Candida species induce vasculitis in mice. We prepared MN fractions from 26 strains of Candida species by conventional hot water extraction and compared vasculitis in DBA/2 mice. The results obtained revealed that the induction of vasculitis and resulting heart failure were significantly dependent on the species; namely, death rates on day 200 were as follows: Candida krusei (100%), Candida albicans (84%), Candida dubliniensis (47%), Candida parapsilosis (44%), Candida glabrata (32%), Candida guilliermondii (20%), and Candida tropicalis (20%). Even for C. albicans, some strains did not induce vasculitis. The present results suggest that MN-induced vasculitis is strongly dependent on the species and strains of Candida, and also that the MN fractions of some non-albicans Candida induce similar toxicity to those of C. albicans.
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Affiliation(s)
- Hiroaki Tanaka
- Laboratory for Immunopharmacology of Microbial Products, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences.,Department of Pharmacy, Kyorin University Hospital
| | - Chiho Yanai
- Laboratory for Immunopharmacology of Microbial Products, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences
| | - Noriko N Miura
- Center for Pharmaceutical Education, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences
| | - Ken-Ichi Ishibashi
- Laboratory for Immunopharmacology of Microbial Products, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences
| | - Daisuke Yamanaka
- Laboratory for Immunopharmacology of Microbial Products, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences
| | - Hiroaki Ohnishi
- Department of Laboratory Medicine, Kyorin University School of Medicine
| | - Naohito Ohno
- Laboratory for Immunopharmacology of Microbial Products, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences
| | - Yoshiyuki Adachi
- Laboratory for Immunopharmacology of Microbial Products, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences
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21
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Differences in fungal immune recognition by monocytes and macrophages: N-mannan can be a shield or activator of immune recognition. ACTA ACUST UNITED AC 2020; 6:100042. [PMID: 33364531 PMCID: PMC7750734 DOI: 10.1016/j.tcsw.2020.100042] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 07/08/2020] [Accepted: 07/08/2020] [Indexed: 02/08/2023]
Abstract
Cytokine response to N-mannan mutants was dependent on the immune cell type used. N-mannan mutants stimulated less cytokines from monocytes but more from macrophages. N-mannan can therefore act as both an immune agonist or an immune shield.
We designed experiments to assess whether fungal cell wall mannans function as an immune shield or an immune agonist. Fungal cell wall β-(1,3)-glucan normally plays a major and dominant role in immune activation. The outer mannan layer has been variously described as an immune shield, because it has the potential to mask the underlying β-(1,3)-glucan, or an immune activator, as it also has the potential to engage with a wide range of mannose detecting PRRs. To resolve this conundrum we examined species-specific differences in host immune recognition in the och1Δ N-mannosylation-deficient mutant background in four species of yeast-like fungi. Irrespective of the fungal species, the cytokine response (TNFα and IL-6) induced by the och1Δ mutants in human monocytes was reduced compared to that of the wild type. In contrast, TNFα production induced by och1Δ was increased, relative to wild type, due to increased β-glucan exposure, when mouse or human macrophages were used. These observations suggest that N-mannan is not a major PAMP for macrophages and that in these cells mannan does shield the fungus from recognition of the inner cell wall β-glucan. However, N-mannan is a significant inducer of cytokine for monocytes. Therefore the metaphor of the fungal “mannan shield” can only be applied to some, but not all, myeloid cells used in immune profiling experiments of fungal species.
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22
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Gannedi V, Ali A, Singh PP, Vishwakarma RA. Total Synthesis of Phospholipomannan of Candida albicans. J Org Chem 2020; 85:7757-7771. [PMID: 32425042 DOI: 10.1021/acs.joc.0c00402] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
First, total synthesis of the cell surface phospholipomannan anchor [β-Manp-(1 → 2)-β-Manp]n-(1 → 2)-β-Manp-(1 → 2)-α-Manp-1 → P-(O → 6)-α-Manp-(1 → 2)-Inositol-1-P-(O → 1)-phytoceramide of Candida albicans is reported. The target phospholipomannan (PLM) anchor poses synthetic challenges such as the unusual kinetically controlled (1 → 2)-β-oligomannan domain, anomeric phosphodiester, and unique phytoceramide lipid tail linked to the glycan through a phosphate group. The synthesis of PLM anchor was accomplished using a convergent block synthetic approach using three main appropriately protected building blocks: (1 → 2)-β-tetramannan repeats, pseudodisaccharide, and phytoceramide-1-H-phosphonate. The most challenging (1 → 2)-β-tetramannan domain was synthesized in one pot using the preactivation method. The phytoceramide-1-H-phosphonate was synthesized through an enantioselective A3 three-component coupling reaction. Finally, the phytoceramide-1-H-phosphonate moiety was coupled with pseudodisaccharide followed by deacetylation to produce the acceptor, which on subsequent coupling with tetramannosyl-H-phosphonate provided the fully protected PLM anchor. Final deprotection was successfully achieved by Pearlman's hydrogenation.
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Affiliation(s)
- Veeranjaneyulu Gannedi
- Medicinal Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu 180001, India.,Academy of Scientific and Innovative Research, Canal Road, Jammu 180001, India
| | - Asif Ali
- Medicinal Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu 180001, India.,Academy of Scientific and Innovative Research, Canal Road, Jammu 180001, India
| | - Parvinder Pal Singh
- Medicinal Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu 180001, India.,Academy of Scientific and Innovative Research, Canal Road, Jammu 180001, India
| | - Ram A Vishwakarma
- Medicinal Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu 180001, India.,Academy of Scientific and Innovative Research, Canal Road, Jammu 180001, India
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23
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Gómez-Gaviria M, Lozoya-Pérez NE, Staniszewska M, Franco B, Niño-Vega GA, Mora-Montes HM. Loss of Kex2 Affects the Candida albicans Cell Wall and Interaction with Innate Immune Cells. J Fungi (Basel) 2020; 6:jof6020057. [PMID: 32365492 PMCID: PMC7344602 DOI: 10.3390/jof6020057] [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: 04/14/2020] [Revised: 04/27/2020] [Accepted: 04/28/2020] [Indexed: 12/18/2022] Open
Abstract
The secretory pathway in Candida albicans involves the protein translocation into the lumen of the endoplasmic reticulum and transport to the Golgi complex, where proteins undergo posttranslational modifications, including glycosylation and proteolysis. The Golgi-resident Kex2 protease is involved in such processing and disruption of its encoding gene affected virulence and dimorphism. These previous studies were performed using cells without URA3 or with URA3 ectopically placed into the KEX2 locus. Since these conditions are known to affect the cellular fitness and the host-fungus interaction, here we generated a kex2Δ null mutant strain with URA3 placed into the neutral locus RPS1. The characterization of this strain showed defects in the cell wall composition, with a reduction in the N-linked mannan content, and the increment in the levels of O-linked mannans, chitin, and β-glucans. The defects in the mannan content are likely linked to changes in Golgi-resident enzymes, as the α-1,2-mannosyltransferase and α-1,6-mannosyltransferase activities were incremented and reduced, respectively. The mutant cells also showed reduced ability to stimulate cytokine production and phagocytosis by human mononuclear cells and macrophages, respectively. Collectively, these data showed that loss of Kex2 affected the cell wall composition, the protein glycosylation pathways, and interaction with innate immune cells.
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Affiliation(s)
- Manuela Gómez-Gaviria
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Guanajuato Gto 36050, Mexico; (M.G.-G.); (N.E.L.-P.); (B.F.); (G.A.N.-V.)
| | - Nancy E. Lozoya-Pérez
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Guanajuato Gto 36050, Mexico; (M.G.-G.); (N.E.L.-P.); (B.F.); (G.A.N.-V.)
| | - Monika Staniszewska
- Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw, Poland;
| | - Bernardo Franco
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Guanajuato Gto 36050, Mexico; (M.G.-G.); (N.E.L.-P.); (B.F.); (G.A.N.-V.)
| | - Gustavo A. Niño-Vega
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Guanajuato Gto 36050, Mexico; (M.G.-G.); (N.E.L.-P.); (B.F.); (G.A.N.-V.)
| | - Hector M. Mora-Montes
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Guanajuato Gto 36050, Mexico; (M.G.-G.); (N.E.L.-P.); (B.F.); (G.A.N.-V.)
- Correspondence: ; Tel.: +52-473-732-0006 (ext. 8193)
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24
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Thomas G, Bain JM, Budge S, Brown AJP, Ames RM. Identifying Candida albicans Gene Networks Involved in Pathogenicity. Front Genet 2020; 11:375. [PMID: 32391057 PMCID: PMC7193023 DOI: 10.3389/fgene.2020.00375] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 03/26/2020] [Indexed: 11/17/2022] Open
Abstract
Candida albicans is a normal member of the human microbiome. It is also an opportunistic pathogen, which can cause life-threatening systemic infections in severely immunocompromized individuals. Despite the availability of antifungal drugs, mortality rates of systemic infections are high and new drugs are needed to overcome therapeutic challenges including the emergence of drug resistance. Targeting known disease pathways has been suggested as a promising avenue for the development of new antifungals. However, <30% of C. albicans genes are verified with experimental evidence of a gene product, and the full complement of genes involved in important disease processes is currently unknown. Tools to predict the function of partially or uncharacterized genes and generate testable hypotheses will, therefore, help to identify potential targets for new antifungal development. Here, we employ a network-extracted ontology to leverage publicly available transcriptomics data and identify potential candidate genes involved in disease processes. A subset of these genes has been phenotypically screened using available deletion strains and we present preliminary data that one candidate, PEP8, is involved in hyphal development and immune evasion. This work demonstrates the utility of network-extracted ontologies in predicting gene function to generate testable hypotheses that can be applied to pathogenic systems. This could represent a novel first step to identifying targets for new antifungal therapies.
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Affiliation(s)
- Graham Thomas
- Biosciences, University of Exeter, Exeter, United Kingdom
| | - Judith M Bain
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Susan Budge
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Alistair J P Brown
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom.,MRC Centre for Medical Mycology at the University of Exeter, Biosciences, University of Exeter, Exeter, United Kingdom
| | - Ryan M Ames
- Biosciences, University of Exeter, Exeter, United Kingdom
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25
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Alam F, Catlow D, Di Maio A, Blair JMA, Hall RA. Candida albicans enhances meropenem tolerance of Pseudomonas aeruginosa in a dual-species biofilm. J Antimicrob Chemother 2020; 75:925-935. [PMID: 31865379 PMCID: PMC7069478 DOI: 10.1093/jac/dkz514] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2019] [Revised: 10/18/2019] [Accepted: 11/12/2019] [Indexed: 02/07/2023] Open
Abstract
BACKGROUND Pseudomonas aeruginosa is an opportunistic bacterium that infects the airways of cystic fibrosis patients, surfaces of surgical and burn wounds, and indwelling medical devices. Patients are prone to secondary fungal infections, with Candida albicans being commonly co-isolated with P. aeruginosa. Both P. aeruginosa and C. albicans are able to form extensive biofilms on the surfaces of mucosa and medical devices. OBJECTIVES To determine whether the presence of C. albicans enhances antibiotic tolerance of P. aeruginosa in a dual-species biofilm. METHODS Single- and dual-species biofilms were established in microtitre plates and the survival of each species was measured following treatment with clinically relevant antibiotics. Scanning electron microscopy and confocal microscopy were used to visualize biofilm structure. RESULTS C. albicans enhances P. aeruginosa biofilm tolerance to meropenem at the clinically relevant concentration of 5 mg/L. This effect is specific to biofilm cultures and is dependent upon C. albicans extracellular matrix polysaccharides, mannan and glucan, with C. albicans cells deficient in glycosylation structures not enhancing P. aeruginosa tolerance to meropenem. CONCLUSIONS We propose that fungal mannan and glucan secreted into the extracellular matrix of P. aeruginosa/C. albicans dual-species biofilms play a central role in enhancing P. aeruginosa tolerance to meropenem, which has direct implications for the treatment of coinfected patients.
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Affiliation(s)
- Farhana Alam
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Dominic Catlow
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Alessandro Di Maio
- Birmingham Advanced Light Microscopy, School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Jessica M A Blair
- Institute of Microbiology and Infection, College of Medical and Dental Sciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Rebecca A Hall
- Institute of Microbiology and Infection, School of Biosciences, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
- Kent Fungal Group, School of Biosciences, University of Kent, Canterbury, CT2 7NZ, UK
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26
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Yanai C, Tanaka H, Miura NN, Ishibashi KI, Yamanaka D, Ohnishi H, Ohno N, Adachi Y. Coronary Vasculitis Induced in Mice by the Cell Wall Mannoprotein of Candida krusei. Biol Pharm Bull 2020; 43:848-858. [PMID: 32161223 DOI: 10.1248/bpb.b19-01060] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Kawasaki disease (KD) is an inflammatory disease that was identified by Professor Tomisaku Kawasaki in 1961. Candida albicans-derived substances, such as the hot water extract of C. albicans (CADS) and Candida water-soluble fraction (CAWS), induced coronary vasculitis similar to KD in mice. An increasing proportion of deep-seated candidiasis cases are caused by non-albicans Candida and are often resistant to antifungal drugs. We herein investigated whether the hot water extract of C. krusei, inherently resistant to fluconazole, induces vasculitis in mice. Three strains of C. krusei, NBRC1395, NBRC1162, and NBRC10737, were cultured in natural (Y) and chemically defined (C) media and cell wall mannoprotein (MN) fractions were prepared by autoclaving cells (CKY1395MN, CKC1395MN, CKY1162MN, CKC1162MN, CKY10737MN, and CKC10737MN). All MN fractions reacted strongly with Concanavalin A (Con A) and dectin-2 and induced anaphylactoid shock in ICR mice. MNs induced severe coronary vasculitis in DBA/2 mice, resulting in cardiac hypertrophy. MNs also induced coronary vasculitis in C57Bl/6 mice. These results suggest that the MNs of non-albicans Candida, such as C. krusei, induce similar toxicity to those of C. albicans.
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Affiliation(s)
- Chiho Yanai
- Laboratory for Immunopharmacology of Microbial Products, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences
| | - Hiroaki Tanaka
- Laboratory for Immunopharmacology of Microbial Products, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences.,Department of Pharmacy, Kyorin University Hospital
| | - Noriko N Miura
- Center for Pharmaceutical Education, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences
| | - Ken-Ichi Ishibashi
- Laboratory for Immunopharmacology of Microbial Products, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences
| | - Daisuke Yamanaka
- Laboratory for Immunopharmacology of Microbial Products, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences
| | - Hiroaki Ohnishi
- Department of Laboratory Medicine, Kyorin University School of Medicine
| | - Naohito Ohno
- Laboratory for Immunopharmacology of Microbial Products, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences
| | - Yoshiyuki Adachi
- Laboratory for Immunopharmacology of Microbial Products, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences
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27
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Khoury ZH, Vila T, Puthran TR, Sultan AS, Montelongo-Jauregui D, Melo MAS, Jabra-Rizk MA. The Role of Candida albicans Secreted Polysaccharides in Augmenting Streptococcus mutans Adherence and Mixed Biofilm Formation: In vitro and in vivo Studies. Front Microbiol 2020; 11:307. [PMID: 32256460 PMCID: PMC7093027 DOI: 10.3389/fmicb.2020.00307] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Accepted: 02/11/2020] [Indexed: 11/13/2022] Open
Abstract
The oral cavity is a complex environment harboring diverse microbial species that often co-exist within biofilms formed on oral surfaces. Within a biofilm, inter-species interactions can be synergistic in that the presence of one organism generates a niche for another enhancing colonization. Among these species are the opportunistic fungal pathogen Candida albicans and the bacterial species Streptococcus mutans, the etiologic agents of oral candidiasis and dental caries, respectively. Recent studies have reported enhanced prevalence of C. albicans in children with caries indicating potential clinical implications for this fungal-bacterial interaction. In this study, we aimed to specifically elucidate the role of C. albicans-derived polysaccharide biofilm matrix components in augmenting S. mutans colonization and mixed biofilm formation. Comparative evaluations of single and mixed species biofilms demonstrated significantly enhanced S. mutans retention in mixed biofilms with C. albicans. Further, S. mutans single species biofilms were enhanced upon exogenous supplementation with purified matrix material derived from C. albicans biofilms. Similarly, growth in C. albicans cell-free spent biofilm culture media enhanced S. mutans single species biofilm formation, however, the observed increase in S. mutans biofilms was significantly affected upon enzymatic digestion of polysaccharides in spent media, identifying C. albicans secreted polysaccharides as a key factor in mediating mixed biofilm formation. The enhanced S. mutans biofilms mediated by the various C. albicans effectors was also demonstrated using confocal laser scanning microscopy. Importantly, a clinically relevant mouse model of oral co-infection was adapted to demonstrate the C. albicans-mediated enhanced S. mutans colonization in a host. Analyses of harvested tissue and scanning electron microscopy demonstrated significantly higher S. mutans retention on teeth and tongues of co-infected mice compared to mice infected only with S. mutans. Collectively, the findings from this study strongly indicate that the secretion of polysacharides from C. albicans in the oral environment may impact the development of S. mutans biofilms, ultimately increasing dental caries and, therefore, Candida oral colonization should be considered as a factor in evaluating the risk of caries.
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Affiliation(s)
- Zaid H Khoury
- Department of Oncology and Diagnostic Sciences, University of Maryland School of Dentistry, Baltimore, MD, United States
| | - Taissa Vila
- Department of Oncology and Diagnostic Sciences, University of Maryland School of Dentistry, Baltimore, MD, United States
| | - Taanya R Puthran
- Department of Oncology and Diagnostic Sciences, University of Maryland School of Dentistry, Baltimore, MD, United States
| | - Ahmed S Sultan
- Department of Oncology and Diagnostic Sciences, University of Maryland School of Dentistry, Baltimore, MD, United States
| | - Daniel Montelongo-Jauregui
- Department of Oncology and Diagnostic Sciences, University of Maryland School of Dentistry, Baltimore, MD, United States
| | - Mary Anne S Melo
- Ph.D. Program in Biomedical Sciences, University of Maryland School of Dentistry, Baltimore, MD, United States.,Division of Operative Dentistry, Department of General Dentistry, University of Maryland School of Dentistry, Baltimore, MD, United States
| | - Mary Ann Jabra-Rizk
- Department of Oncology and Diagnostic Sciences, University of Maryland School of Dentistry, Baltimore, MD, United States.,Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, United States
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28
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The Role of Secretory Pathways in Candida albicans Pathogenesis. J Fungi (Basel) 2020; 6:jof6010026. [PMID: 32102426 PMCID: PMC7151058 DOI: 10.3390/jof6010026] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2020] [Revised: 02/19/2020] [Accepted: 02/20/2020] [Indexed: 12/17/2022] Open
Abstract
Candida albicans is a fungus that is a commensal organism and a member of the normal human microbiota. It has the ability to transition into an opportunistic invasive pathogen. Attributes that support pathogenesis include secretion of virulence-associated proteins, hyphal formation, and biofilm formation. These processes are supported by secretion, as defined in the broad context of membrane trafficking. In this review, we examine the role of secretory pathways in Candida virulence, with a focus on the model opportunistic fungal pathogen, Candida albicans.
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29
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Lin GY, Chang CF, Lan CY. The interaction Between Carbohydrates and the Antimicrobial Peptide P-113Tri is Involved in the Killing of Candida albicans. Microorganisms 2020; 8:microorganisms8020299. [PMID: 32098211 PMCID: PMC7074873 DOI: 10.3390/microorganisms8020299] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2020] [Revised: 02/19/2020] [Accepted: 02/19/2020] [Indexed: 12/14/2022] Open
Abstract
The emergence of drug resistance to Candida albicans is problematic in the clinical setting. Therefore, developing new antifungal drugs is in high demand. Our previous work indicated that the antimicrobial peptide P-113Tri exhibited higher antifungal activity against planktonic cells, biofilm cells, and clinical isolates of Candida species compared to its parental peptide P-113. In this study, we further investigated the difference between these two peptides in their mechanisms against C. albicans. Microscopic examination showed that P-113 rapidly gained access to C. albicans cells. However, most of the P-113Tri remained on the cell surface. Moreover, using a range of cell wall-defective mutants and competition assays, the results indicated that phosphomannan and N-linked mannan in the cell wall are important for peptide binding to C. albicans cells. Furthermore, the addition of exogenous phosphosugars reduced the efficacy of the peptide, suggesting that negatively charged phosphosugars also contributed to the peptide binding to the cell wall polysaccharides. Finally, using a glycan array, P-113Tri, but not P-113, can bind to other glycans commonly present on other microbial and mammalian cells. Together, these results suggest that P-113 and P-113Tri have fundamental differences in their interaction with C. albicans and candidacidal activities.
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Affiliation(s)
- Guan-Yu Lin
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu 30013, Taiwan;
| | - Chuan-Fa Chang
- Department of Medical Laboratory Science and Biotechnology, National Cheng Kung University, Tainan 70101, Taiwan;
| | - Chung-Yu Lan
- Institute of Molecular and Cellular Biology, National Tsing Hua University, Hsinchu 30013, Taiwan;
- Department of Life Science, National Tsing Hua University, Hsinchu 30013, Taiwan
- Correspondence: ; Tel.: +886-3-574-2473; Fax: +886-3-571-5934
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30
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Hernández-Chávez MJ, Clavijo-Giraldo DM, Novák Á, Lozoya-Pérez NE, Martínez-Álvarez JA, Salinas-Marín R, Hernández NV, Martínez-Duncker I, Gácser A, Mora-Montes HM. Role of Protein Mannosylation in the Candida tropicalis-Host Interaction. Front Microbiol 2019; 10:2743. [PMID: 31849889 PMCID: PMC6892782 DOI: 10.3389/fmicb.2019.02743] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2019] [Accepted: 11/11/2019] [Indexed: 12/12/2022] Open
Abstract
Mannans are components of the fungal wall attached to proteins via N- or O-linkages. In Candida albicans, Och1 is an α1,6-mannosyltransferase that adds the first mannose unit to the N-linked mannan outer chain; whereas Pmr1 is an ion pump that imports Mn2+ into the Golgi lumen. This cation is the cofactor of Golgi-resident mannosyltransferases, and thus Pmr1 is involved in the synthesis of both N- and O-linked mannans. Since we currently have limited information about the genetic network behind the Candida tropicalis protein mannosylation machinery, we disrupted OCH1 and PMR1 in this organism. The C. tropicalis pmr1Δ and och1Δ mutants showed increased doubling times, aberrant colony and cellular morphology, reduction in the wall mannan content, and increased susceptibility to wall perturbing agents. These changes were accompanied by increased exposure of both β1,3-glucan and chitin at the wall surface of both mutant strains. Our results showed that O-linked mannans are dispensable for cytokine production by human mononuclear cells, but N-linked mannans and β1,3-glucan are key ligands to trigger cytokine production in a co-stimulatory pathway involving dectin-1 and mannose receptor. Moreover, we found that the N-linked mannan core found on the surface of C. tropicalis och1Δ null mutant was capable of inducing cytokine production; and that a mannan-independent pathway for IL-10 production is present in the C. tropicalis-mononuclear cell interaction. Both mutant strains showed virulence attenuation in the Galleria mellonella and the mouse model of systemic candidiasis. Therefore, mannans are relevant for cell wall composition and organization, and for the C. tropicalis-host interaction.
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Affiliation(s)
- Marco J Hernández-Chávez
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Guanajuato, Mexico
| | - Diana M Clavijo-Giraldo
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Guanajuato, Mexico
| | - Ádám Novák
- Department of Microbiology, University of Szeged, Szeged, Hungary
| | - Nancy E Lozoya-Pérez
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Guanajuato, Mexico
| | - José A Martínez-Álvarez
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Guanajuato, Mexico
| | - Roberta Salinas-Marín
- Laboratorio de Glicobiología Humana y Diagnóstico Molecular, Universidad Autónoma del Estado de Morelos, Cuernavaca, Mexico
| | - Nahúm V Hernández
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Guanajuato, Mexico
| | - Iván Martínez-Duncker
- Laboratorio de Glicobiología Humana y Diagnóstico Molecular, Universidad Autónoma del Estado de Morelos, Cuernavaca, Mexico
| | - Attila Gácser
- Department of Microbiology, University of Szeged, Szeged, Hungary.,MTA-SZTE "Lendület" Mycobiome Research Group, University of Szeged, Szeged, Hungary
| | - Héctor M Mora-Montes
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Guanajuato, Mexico
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Targeting the fungal cell wall: current therapies and implications for development of alternative antifungal agents. Future Med Chem 2019; 11:869-883. [PMID: 30994368 DOI: 10.4155/fmc-2018-0465] [Citation(s) in RCA: 60] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Fungal infections are a worldwide problem associated with high morbidity and mortality. There are relatively few antifungal agents, and resistance has emerged within these pathogens for the newest antifungal drugs. As the fungal cell wall is critical for growth and development, it is one of the most important targets for drug development. In this review, the currently available cell wall inhibitors and suitable drug candidates for the treatment of fungal infections are explored. Future studies of the fungal cell wall and compounds that have detrimental effects on this important outer structural layer could aid in antifungal drug discovery and lead to the development of alternative cell wall inhibitors to fill gaps in clinical therapies for difficult-to-treat fungal infections.
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Hernández-Chávez MJ, Franco B, Clavijo-Giraldo DM, Hernández NV, Estrada-Mata E, Mora-Montes HM. Role of protein phosphomannosylation in the Candida tropicalis-macrophage interaction. FEMS Yeast Res 2019; 18:4989128. [PMID: 29718196 DOI: 10.1093/femsyr/foy053] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 04/26/2018] [Indexed: 12/16/2022] Open
Abstract
Candida tropicalis is an opportunistic fungal pathogen responsible for mucosal and systemic infections. The cell wall is the initial contact point between a fungal cell and the host immune system, and mannoproteins are important components that play key roles when interacting with host cells. In Candida albicans, mannans are modified by mannosyl-phosphate moieties, named phosphomannans, which can work as molecular scaffolds to synthesize β1,2-mannooligosaccharides, and MNN4 is a positive regulator of the phosphomannosylation pathway. Here, we showed that C. tropicalis also displays phosphomannans on the cell surface, but the amount of this cell wall component varies depending on the fungal strain. We also identified a functional ortholog of CaMNN4 in C. tropicalis. Disruption of this gene caused depletion of phosphomannan content. The C. tropicalis mnn4Δ did not show defects in the ability to stimulate cytokine production by human mononuclear cells but displayed virulence attenuation in an insect model of candidiasis. When the mnn4Δ-macrophage interaction was analyzed, results showed that presence of cell wall phosphomannan was critical for C. tropicalis phagocytosis. Finally, our results strongly suggest a differential role for phosphomannans during phagocytosis of C. albicans and C. tropicalis.
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Affiliation(s)
- Marco J Hernández-Chávez
- Departamento de Biología, Universidad de Guanajuato, Noria Alta s/n, col. Noria Alta, C.P. 36050, Guanajuato, Gto., México
| | - Bernardo Franco
- Departamento de Biología, Universidad de Guanajuato, Noria Alta s/n, col. Noria Alta, C.P. 36050, Guanajuato, Gto., México
| | - Diana M Clavijo-Giraldo
- Departamento de Biología, Universidad de Guanajuato, Noria Alta s/n, col. Noria Alta, C.P. 36050, Guanajuato, Gto., México
| | - Nahúm V Hernández
- Departamento de Biología, Universidad de Guanajuato, Noria Alta s/n, col. Noria Alta, C.P. 36050, Guanajuato, Gto., México
| | - Eine Estrada-Mata
- Departamento de Biología, Universidad de Guanajuato, Noria Alta s/n, col. Noria Alta, C.P. 36050, Guanajuato, Gto., México
| | - Héctor Manuel Mora-Montes
- Departamento de Biología, Universidad de Guanajuato, Noria Alta s/n, col. Noria Alta, C.P. 36050, Guanajuato, Gto., México
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Negrini TDC, Koo H, Arthur RA. Candida–Bacterial Biofilms and Host–Microbe Interactions in Oral Diseases. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1197:119-141. [DOI: 10.1007/978-3-030-28524-1_10] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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Childers DS, Avelar GM, Bain JM, Larcombe DE, Pradhan A, Budge S, Heaney H, Brown AJP. Impact of the Environment upon the Candida albicans Cell Wall and Resultant Effects upon Immune Surveillance. Curr Top Microbiol Immunol 2019; 425:297-330. [PMID: 31781866 DOI: 10.1007/82_2019_182] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The fungal cell wall is an essential organelle that maintains cellular morphology and protects the fungus from environmental insults. For fungal pathogens such as Candida albicans, it provides a degree of protection against attack by host immune defences. However, the cell wall also presents key epitopes that trigger host immunity and attractive targets for antifungal drugs. Rather than being a rigid shield, it has become clear that the fungal cell wall is an elastic organelle that permits rapid changes in cell volume and the transit of large liposomal particles such as extracellular vesicles. The fungal cell wall is also flexible in that it adapts to local environmental inputs, thereby enhancing the fitness of the fungus in these microenvironments. Recent evidence indicates that this cell wall adaptation affects host-fungus interactions by altering the exposure of major cell wall epitopes that are recognised by innate immune cells. Therefore, we discuss the impact of environmental adaptation upon fungal cell wall structure, and how this affects immune recognition, focussing on C. albicans and drawing parallels with other fungal pathogens.
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Affiliation(s)
- Delma S Childers
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD, UK
| | - Gabriela M Avelar
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD, UK
| | - Judith M Bain
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD, UK
| | - Daniel E Larcombe
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD, UK
- Medical Research Council Centre for Medical Mycology, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK
| | - Arnab Pradhan
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD, UK
- Medical Research Council Centre for Medical Mycology, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK
| | - Susan Budge
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD, UK
| | - Helen Heaney
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD, UK
| | - Alistair J P Brown
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, AB25 2ZD, UK.
- Medical Research Council Centre for Medical Mycology, University of Exeter, Geoffrey Pope Building, Stocker Road, Exeter, EX4 4QD, UK.
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Lee KK, Kubo K, Abdelaziz JA, Cunningham I, de Silva Dantas A, Chen X, Okada H, Ohya Y, Gow NAR. Yeast species-specific, differential inhibition of β-1,3-glucan synthesis by poacic acid and caspofungin. Cell Surf 2018; 3:12-25. [PMID: 30370375 PMCID: PMC6195761 DOI: 10.1016/j.tcsw.2018.09.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Revised: 08/16/2018] [Accepted: 09/04/2018] [Indexed: 01/27/2023] Open
Abstract
Poacic acid antifungal activity is both strains and species dependent for a range of Candida species. The calcineurin pathway regulates poacic acid sensitivity in C. albicans. Point mutations in β-1,3-glucan synthase Fks1 differentially affect poacic acid and echinocandin sensitivity.
The rise of widespread antifungal resistance fuels the need to explore new classes of inhibitory molecules as potential novel inhibitors. Recently a plant natural product poacic acid (PA) was shown to inhibit β-1,3-glucan synthesis, and to have antifungal activity against a range of plant pathogens and against Saccharomyces cerevisiae. As with the echinocandins, such as caspofungin, PA targets the synthesis of cell wall β-1,3-glucan and has potential utility in the treatment of medically important fungi. However, the antifungal activity of PA against human pathogenic Candida species has not been explored and the precise mode of action of this compound is not understood. Here, we show that PA sensitivity is regulated by the calcineurin pathway and that susceptibility to PA varied significantly between Candida species, but did not correlate with in vitro β-glucan synthase activity, cell wall β-glucan content or the sensitivity of the species to caspofungin. Strains with point mutations (S645Y or S645P) in the hotspot1 region of the β-1,3-glucan synthase subunit Fks1, had decreased sensitivity to caspofungin but increased sensitivity to PA. C. guilliermondii, C. orthopsilosis, and C. parapsilosis were more sensitive to PA than C. albicans, C. dubliniensis, C. tropicalis, and C. glabrata. These observations suggest that there are significant differences in the mode of action of PA and caspofungin and that PA or PA analogues are not likely to have broad spectrum activity in the treatment of Candida infections.
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Affiliation(s)
- Keunsook K Lee
- The Aberdeen Fungal Group, MRC Centre for Medical Mycology, School of Medicine, Medical Sciences & Nutrition, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, UK
| | - Karen Kubo
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, University of Tokyo, Kashiwa, Chiba, Japan.,AIST-UTokyo Advanced Operando-Measurement Technology Open Innovation Laboratory (OPERANDO-OIL), National Institute of Advanced Industrial Science and Technology (AIST), Kashiwa, Chiba, 277-8565, Japan
| | - Jehan Abdelmoneim Abdelaziz
- The Aberdeen Fungal Group, MRC Centre for Medical Mycology, School of Medicine, Medical Sciences & Nutrition, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, UK
| | - Iain Cunningham
- The Aberdeen Fungal Group, MRC Centre for Medical Mycology, School of Medicine, Medical Sciences & Nutrition, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, UK
| | - Alessandra de Silva Dantas
- The Aberdeen Fungal Group, MRC Centre for Medical Mycology, School of Medicine, Medical Sciences & Nutrition, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, UK
| | - Xiaolin Chen
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, University of Tokyo, Kashiwa, Chiba, Japan
| | - Hiroki Okada
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, University of Tokyo, Kashiwa, Chiba, Japan
| | - Yoshikazu Ohya
- Department of Integrated Biosciences, Graduate School of Frontier Sciences, University of Tokyo, Kashiwa, Chiba, Japan.,AIST-UTokyo Advanced Operando-Measurement Technology Open Innovation Laboratory (OPERANDO-OIL), National Institute of Advanced Industrial Science and Technology (AIST), Kashiwa, Chiba, 277-8565, Japan
| | - Neil A R Gow
- The Aberdeen Fungal Group, MRC Centre for Medical Mycology, School of Medicine, Medical Sciences & Nutrition, Institute of Medical Sciences, University of Aberdeen, Foresterhill, Aberdeen, UK
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36
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Morad HOJ, Wild AM, Wiehr S, Davies G, Maurer A, Pichler BJ, Thornton CR. Pre-clinical Imaging of Invasive Candidiasis Using ImmunoPET/MR. Front Microbiol 2018; 9:1996. [PMID: 30190717 PMCID: PMC6115526 DOI: 10.3389/fmicb.2018.01996] [Citation(s) in RCA: 20] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Accepted: 08/08/2018] [Indexed: 12/17/2022] Open
Abstract
The human commensal yeast Candida is the fourth most common cause of hospital-acquired bloodstream infections, with Candida albicans accounting for the majority of the >400,000 life-threatening infections annually. Diagnosis of invasive candidiasis (IC), a disease encompassing candidemia (blood-borne yeast infection) and deep-seated organ infections, is a major challenge since clinical manifestations of the disease are indistinguishable from viral, bacterial and other fungal diseases, and diagnostic tests for biomarkers in the bloodstream such as PCR, ELISA, and pan-fungal β-D-glucan lack either standardization, sensitivity, or specificity. Blood culture remains the gold standard for diagnosis, but test sensitivity is poor and turn-around time slow. Furthermore, cultures can only be obtained when the yeast resides in the bloodstream, with samples recovered from hematogenous infections often yielding negative results. Consequently, there is a pressing need for a diagnostic test that allows the identification of metastatic foci in deep-seated Candida infections, without the need for invasive biopsy. Here, we report the development of a highly specific mouse IgG3 monoclonal antibody (MC3) that binds to a putative β-1,2-mannan epitope present in high molecular weight mannoproteins and phospholipomannans on the surface of yeast and hyphal morphotypes of C. albicans, and its use as a [64Cu]NODAGA-labeled tracer for whole-body pre-clinical imaging of deep-seated C. albicans infections using antibody-guided positron emission tomography and magnetic resonance imaging (immunoPET/MRI). When used in a mouse intravenous (i.v.) challenge model that faithfully mimics disseminated C. albicans infections in humans, the [64Cu]NODAGA-MC3 tracer accurately detects infections of the kidney, the principal site of blood-borne candidiasis in this model. Using a strain of the emerging human pathogen Candida auris that reacts with MC3 in vitro, but which is non-infective in i.v. challenged mice, we demonstrate the accuracy of the tracer in diagnosing invasive infections in vivo. This pre-clinical study demonstrates the principle of using antibody-guided molecular imaging for detection of deep organ infections in IC, without the need for invasive tissue biopsy.
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Affiliation(s)
- Hassan O J Morad
- Wolfson Centre for Age-Related Diseases, King's College London, London, United Kingdom
| | - Anna-Maria Wild
- Department of Physical Intelligence, Max Planck Institute for Intelligent Systems, Stuttgart, Germany.,Department of Preclinical Imaging and Radiopharmacy, Werner Siemens Imaging Center, Eberhard Karls University of Tübingen, Tübingen, Germany
| | - Stefan Wiehr
- Department of Physical Intelligence, Max Planck Institute for Intelligent Systems, Stuttgart, Germany.,Department of Preclinical Imaging and Radiopharmacy, Werner Siemens Imaging Center, Eberhard Karls University of Tübingen, Tübingen, Germany
| | - Genna Davies
- ISCA Diagnostics Ltd. and Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
| | - Andreas Maurer
- Department of Preclinical Imaging and Radiopharmacy, Werner Siemens Imaging Center, Eberhard Karls University of Tübingen, Tübingen, Germany
| | - Bernd J Pichler
- Department of Preclinical Imaging and Radiopharmacy, Werner Siemens Imaging Center, Eberhard Karls University of Tübingen, Tübingen, Germany
| | - Christopher R Thornton
- ISCA Diagnostics Ltd. and Biosciences, College of Life and Environmental Sciences, University of Exeter, Exeter, United Kingdom
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Portrait of Matrix Gene Expression in Candida glabrata Biofilms with Stress Induced by Different Drugs. Genes (Basel) 2018; 9:genes9040205. [PMID: 29642649 PMCID: PMC5924547 DOI: 10.3390/genes9040205] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Revised: 03/29/2018] [Accepted: 04/05/2018] [Indexed: 01/22/2023] Open
Abstract
(1) Background: Candida glabrata is one of the most significant Candida species associated with severe cases of candidiasis. Biofilm formation is an important feature, closely associated with antifungal resistance, involving alterations of gene expression or mutations, which can result in the failure of antifungal treatments. Hence, the main goal of this work was to evaluate the role of a set of genes, associated with matrix production, in the resistance of C. glabrata biofilms to antifungal drugs. (2) Methods: the determination of the expression of BGL2, XOG1, FKS1, FKS2, GAS2, KNH1, UGP1, and MNN2 genes in 48-h biofilm’s cells of three C. glabrata strains was performed through quantitative real-time PCR (RT-qPCR), after contact with Fluconazole (Flu), Amphotericin B (AmB), Caspofungin (Csf), or Micafungin (Mcf). (3) Results: Mcf induced a general overexpression of the selected genes. It was verified that the genes related to the production of β-1,3-glucans (BGL2, XOG1, GAS2) had the highest expressions. (4) Conclusion: though β-1,6-glucans and mannans are an essential part of the cell and biofilm matrix, C. glabrata biofilm cells seem to contribute more to the replacement of β-1,3-glucans. Thus, these biopolymers seem to have a greater impact on the biofilm matrix composition and, consequently, a role in the biofilm resistance to antifungal drugs.
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Richardson JP, Moyes DL, Ho J, Naglik JR. Candida innate immunity at the mucosa. Semin Cell Dev Biol 2018; 89:58-70. [PMID: 29501618 DOI: 10.1016/j.semcdb.2018.02.026] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 02/27/2018] [Indexed: 12/17/2022]
Abstract
The tremendous diversity in microbial species that colonise the mucosal surfaces of the human body is only now beginning to be fully appreciated. Distinguishing between the behaviour of commensal microbes and harmful pathogens that reside at mucosal sites in the body is a complex, and exquisitely fine-tuned process central to mucosal health. The fungal pathobiont Candida albicans is frequently isolated from mucosal surfaces with an asymptomatic carriage rate of approximately 60% in the human population. While normally a benign member of the microbiota, overgrowth of C. albicans often results in localised mucosal infection causing morbidity in otherwise healthy individuals, and invasive infection that often causes death in the absence of effective immune defence. C. albicans triggers numerous innate immune responses at mucosal surfaces, and detection of C. albicans hyphae in particular, stimulates the production of antimicrobial peptides, danger-associated molecular patterns and cytokines that function to reduce fungal burdens during infection. This review will summarise our current understanding of innate immune responses to C. albicans at mucosal surfaces.
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Affiliation(s)
| | - David L Moyes
- Centre for Host-Microbiome Interactions, Mucosal & Salivary Biology Division, Dental Institute, King's College London, UK.
| | - Jemima Ho
- Mucosal & Salivary Biology Division, Dental Institute, King's College London, UK.
| | - Julian R Naglik
- Mucosal & Salivary Biology Division, Dental Institute, King's College London, UK.
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López-Ramírez LA, Hernández NV, Lozoya-Pérez NE, Lopes-Bezerra LM, Mora-Montes HM. Functional characterization of the Sporothrix schenckii Ktr4 and Ktr5, mannosyltransferases involved in the N-linked glycosylation pathway. Res Microbiol 2018; 169:188-197. [PMID: 29476824 DOI: 10.1016/j.resmic.2018.02.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Revised: 02/05/2018] [Accepted: 02/06/2018] [Indexed: 01/22/2023]
Abstract
Sporothrix schenckii is one of the causative agents of the deep-seated mycosis sporotrichosis, a fungal infection with worldwide distribution. Fungus-specific molecules and biosynthetic pathways are potential targets for the development of new antifungal drugs. The MNT1/KRE2 gene family is a group of genes that encode fungus-specific Golgi-resident mannosyltransferases that participate in the synthesis of O-linked and N-linked glycans. While this family is composed of five and nine members in Candida albicans and Saccharomyces cerevisiae, respectively, the S. schenckii genome contains only three putative members. MNT1 has been previously characterized as an enzyme that participates in the synthesis of both N-linked and O-linked glycans. Here, we aimed to establish the functional role of the two remaining family members, KTR4 and KTR5, in the protein glycosylation pathways by using heterologous complementation in C. albicans mutants lacking genes of the MNT1/KRE2 family. The two S. schenckii genes restored defects in the elaboration of N-linked glycans, but no complementation of mutants that synthesize truncated O-linked glycans was observed. Therefore, our results suggest that MNT1 is the sole member with a role in O-linked glycan elaboration, whereas the three family members have redundant activity in the S. schenckii N-linked glycan synthesis.
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Affiliation(s)
- Luz A López-Ramírez
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Noria Alta s/n, col. Noria Alta, C.P. 36050, Guanajuato Gto., Mexico
| | - Nahúm V Hernández
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Noria Alta s/n, col. Noria Alta, C.P. 36050, Guanajuato Gto., Mexico
| | - Nancy E Lozoya-Pérez
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Noria Alta s/n, col. Noria Alta, C.P. 36050, Guanajuato Gto., Mexico
| | - Leila M Lopes-Bezerra
- Laboratory of Cellular Mycology and Proteomics, Universidade do Estado do Rio de Janeiro, Brazil; Faculdade de Farmácia, Universidade de São Paulo, Brazil
| | - Héctor M Mora-Montes
- Departamento de Biología, División de Ciencias Naturales y Exactas, Campus Guanajuato, Universidad de Guanajuato, Noria Alta s/n, col. Noria Alta, C.P. 36050, Guanajuato Gto., Mexico.
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40
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Walker L, Sood P, Lenardon MD, Milne G, Olson J, Jensen G, Wolf J, Casadevall A, Adler-Moore J, Gow NAR. The Viscoelastic Properties of the Fungal Cell Wall Allow Traffic of AmBisome as Intact Liposome Vesicles. mBio 2018; 9:e02383-17. [PMID: 29437927 PMCID: PMC5801470 DOI: 10.1128/mbio.02383-17] [Citation(s) in RCA: 111] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2017] [Accepted: 01/08/2018] [Indexed: 01/25/2023] Open
Abstract
The fungal cell wall is a critically important structure that represents a permeability barrier and protective shield. We probed Candida albicans and Cryptococcus neoformans with liposomes containing amphotericin B (AmBisome), with or without 15-nm colloidal gold particles. The liposomes have a diameter of 60 to 80 nm, and yet their mode of action requires them to penetrate the fungal cell wall to deliver amphotericin B to the cell membrane, where it binds to ergosterol. Surprisingly, using cryofixation techniques with electron microscopy, we observed that the liposomes remained intact during transit through the cell wall of both yeast species, even though the predicted porosity of the cell wall (pore size, ~5.8 nm) is theoretically too small to allow these liposomes to pass through intact. C. albicans mutants with altered cell wall thickness and composition were similar in both their in vitro AmBisome susceptibility and the ability of liposomes to penetrate the cell wall. AmBisome exposed to ergosterol-deficient C. albicans failed to penetrate beyond the mannoprotein-rich outer cell wall layer. Melanization of C. neoformans and the absence of amphotericin B in the liposomes were also associated with a significant reduction in liposome penetration. Therefore, AmBisome can reach cell membranes intact, implying that fungal cell wall viscoelastic properties are permissive to vesicular structures. The fact that AmBisome can transit through chemically diverse cell wall matrices when these liposomes are larger than the theoretical cell wall porosity suggests that the wall is capable of rapid remodeling, which may also be the mechanism for release of extracellular vesicles.IMPORTANCE AmBisome is a broad-spectrum fungicidal antifungal agent in which the hydrophobic polyene antibiotic amphotericin B is packaged within a 60- to 80-nm liposome. The mode of action involves perturbation of the fungal cell membrane by selectively binding to ergosterol, thereby disrupting membrane function. We report that the AmBisome liposome transits through the cell walls of both Candida albicans and Cryptococcus neoformans intact, despite the fact that the liposome is larger than the theoretical cell wall porosity. This implies that the cell wall has deformable, viscoelastic properties that are permissive to transwall vesicular traffic. These observations help explain the low toxicity of AmBisome, which can deliver its payload directly to the cell membrane without unloading the polyene in the cell wall. In addition, these findings suggest that extracellular vesicles may also be able to pass through the cell wall to deliver soluble and membrane-bound effectors and other molecules to the extracellular space.
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Affiliation(s)
- Louise Walker
- Aberdeen Fungal Group, Institute of Medical Sciences, Medical Research Council Centre for Medical Mycology at the University of Aberdeen, Foresterhill, Aberdeen, United Kingdom
| | - Prashant Sood
- Aberdeen Fungal Group, Institute of Medical Sciences, Medical Research Council Centre for Medical Mycology at the University of Aberdeen, Foresterhill, Aberdeen, United Kingdom
| | - Megan D Lenardon
- Aberdeen Fungal Group, Institute of Medical Sciences, Medical Research Council Centre for Medical Mycology at the University of Aberdeen, Foresterhill, Aberdeen, United Kingdom
- School of Biotechnology and Biomolecular Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Gillian Milne
- Aberdeen Fungal Group, Institute of Medical Sciences, Medical Research Council Centre for Medical Mycology at the University of Aberdeen, Foresterhill, Aberdeen, United Kingdom
| | - Jon Olson
- Gilead Sciences Inc., San Dimas, California, USA
| | | | - Julie Wolf
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, USA
| | - Arturo Casadevall
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, New York, USA
| | | | - Neil A R Gow
- Aberdeen Fungal Group, Institute of Medical Sciences, Medical Research Council Centre for Medical Mycology at the University of Aberdeen, Foresterhill, Aberdeen, United Kingdom
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Targeting Candida spp. to develop antifungal agents. Drug Discov Today 2018; 23:802-814. [PMID: 29353694 DOI: 10.1016/j.drudis.2018.01.003] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2017] [Revised: 12/09/2017] [Accepted: 01/04/2018] [Indexed: 01/15/2023]
Abstract
Invasive fungal infections are a complex challenge throughout the world because of their high incidence, mainly in critically ill patients, and high mortality rates. The antifungal agents currently available are limited; thus, there is a need for the rapid development of new drugs. In silico methods are a modern strategy to explore interactions between new compounds and specific fungal targets, but they depend on precise genetic information. Here, we discuss the main Candida spp. target genes, including information about null mutants, virulence, cytolocalization, co-regulatory genes, and compounds that are related to protein expression. These data will provide a basis for the future in silico development of antifungal drugs.
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42
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Garfoot AL, Goughenour KD, Wüthrich M, Rajaram MVS, Schlesinger LS, Klein BS, Rappleye CA. O-Mannosylation of Proteins Enables Histoplasma Yeast Survival at Mammalian Body Temperatures. mBio 2018; 9:e02121-17. [PMID: 29295913 PMCID: PMC5750402 DOI: 10.1128/mbio.02121-17] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 11/27/2017] [Indexed: 01/30/2023] Open
Abstract
The ability to grow at mammalian body temperatures is critical for pathogen infection of humans. For the thermally dimorphic fungal pathogen Histoplasma capsulatum, elevated temperature is required for differentiation of mycelia or conidia into yeast cells, a step critical for invasion and replication within phagocytic immune cells. Posttranslational glycosylation of extracellular proteins characterizes factors produced by the pathogenic yeast cells but not those of avirulent mycelia, correlating glycosylation with infection. Histoplasma yeast cells lacking the Pmt1 and Pmt2 protein mannosyltransferases, which catalyze O-linked mannosylation of proteins, are severely attenuated during infection of mammalian hosts. Cells lacking Pmt2 have altered surface characteristics that increase recognition of yeast cells by the macrophage mannose receptor and reduce recognition by the β-glucan receptor Dectin-1. Despite these changes, yeast cells lacking these factors still associate with and survive within phagocytes. Depletion of macrophages or neutrophils in vivo does not recover the virulence of the mutant yeast cells. We show that yeast cells lacking Pmt functions are more sensitive to thermal stress in vitro and consequently are unable to productively infect mice, even in the absence of fever. Treatment of mice with cyclophosphamide reduces the normal core body temperature of mice, and this decrease is sufficient to restore the infectivity of O-mannosylation-deficient yeast cells. These findings demonstrate that O-mannosylation of proteins increases the thermotolerance of Histoplasma yeast cells, which facilitates infection of mammalian hosts.IMPORTANCE For dimorphic fungal pathogens, mammalian body temperature can have contrasting roles. Mammalian body temperature induces differentiation of the fungal pathogen Histoplasma capsulatum into a pathogenic state characterized by infection of host phagocytes. On the other hand, elevated temperatures represent a significant barrier to infection by many microbes. By functionally characterizing cells lacking O-linked mannosylation enzymes, we show that protein mannosylation confers thermotolerance on H. capsulatum, enabling infection of mammalian hosts.
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Affiliation(s)
- Andrew L Garfoot
- Department of Microbiology, Ohio State University, Columbus, Ohio, USA
| | | | - Marcel Wüthrich
- Department of Pediatrics, University of Wisconsin, Madison, Wisconsin, USA
| | - Murugesan V S Rajaram
- Department of Microbial Infection and Immunity, Center for Microbial Interface Biology, Ohio State University, Columbus, Ohio, USA
| | - Larry S Schlesinger
- Department of Microbial Infection and Immunity, Center for Microbial Interface Biology, Ohio State University, Columbus, Ohio, USA
| | - Bruce S Klein
- Department of Pediatrics, University of Wisconsin, Madison, Wisconsin, USA
- Departments of Medicine and Medical Microbiology and Immunology, University of Wisconsin, Madison, Wisconsin, USA
| | - Chad A Rappleye
- Department of Microbiology, Ohio State University, Columbus, Ohio, USA
- Department of Microbial Infection and Immunity, Center for Microbial Interface Biology, Ohio State University, Columbus, Ohio, USA
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Muszewska A, Piłsyk S, Perlińska-Lenart U, Kruszewska JS. Diversity of Cell Wall Related Proteins in Human Pathogenic Fungi. J Fungi (Basel) 2017; 4:E6. [PMID: 29371499 PMCID: PMC5872309 DOI: 10.3390/jof4010006] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Revised: 12/13/2017] [Accepted: 12/25/2017] [Indexed: 02/06/2023] Open
Abstract
The cell wall is one of the major keys to fungal identity. Fungi use their cell wall to sense the environment, and localize nutrients and competing microorganism. Pathogenic species additionally modify their cell walls to hide from a host's immune system. With the growing number of fungal infections and alarming shortage of available drugs, we are in need of new approaches to fight pathogens. The cell wall seems to be a natural target, since animal host cells are devoid of it. The current knowledge about fungal cell wall components is often limited, and there is huge diversity both in structure and composition between species. In order to compare the distribution of diverse proteins involved in cell wall biosynthesis and maintenance, we performed sequence homology searches against 24 fungal proteomes from distinct taxonomic groups, all reported as human pathogens. This approach led to identification of 4014 cell wall proteins (CWPs), and enabled us to speculate about cell wall composition in recently sequenced pathogenic fungi with limited experimental information. We found large expansions of several CWP families, in particular taxa, and a number of new CWPs possibly involved in evading host immune recognition. Here, we present a comprehensive evolutionary history of fungal CWP families in the context of the fungal tree of life.
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Affiliation(s)
- Anna Muszewska
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-792 Warsaw, Poland.
| | - Sebastian Piłsyk
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-792 Warsaw, Poland.
| | | | - Joanna S Kruszewska
- Institute of Biochemistry and Biophysics, Polish Academy of Sciences, 02-792 Warsaw, Poland.
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Naglik JR, König A, Hube B, Gaffen SL. Candida albicans-epithelial interactions and induction of mucosal innate immunity. Curr Opin Microbiol 2017; 40:104-112. [PMID: 29156234 PMCID: PMC5733685 DOI: 10.1016/j.mib.2017.10.030] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 10/27/2017] [Accepted: 10/30/2017] [Indexed: 12/24/2022]
Abstract
Candida albicans is a human fungal pathogen that causes millions of mucosal and life-threatening infections annually. C. albicans initially interacts with epithelial cells, resulting in fungal recognition and the formation of hyphae. Hypha formation is critical for host cell damage and immune activation, which are both driven by the secretion of Candidalysin, a recently discovered peptide toxin. Epithelial activation leads to the production of inflammatory mediators that recruit innate immune cells including neutrophils, macrophages and innate Type 17 cells, which together work with epithelial cells to clear the fungal infection. This review will focus on the recent discoveries that have advanced our understanding of C. albicans-epithelial interactions and the induction of mucosal innate immunity.
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Affiliation(s)
- Julian R Naglik
- Mucosal and Salivary Biology Division, King's College London Dental Institute, London SE1 1UL, United Kingdom.
| | - Annika König
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology, Hans-Knoell-Institute, Jena, Germany
| | - Bernhard Hube
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology, Hans-Knoell-Institute, Jena, Germany; Friedrich Schiller University, Jena, Germany; Center for Sepsis Control and Care, University Hospital, Jena, Germany
| | - Sarah L Gaffen
- Division of Rheumatology & Clinical Immunology, University of Pittsburgh, Pittsburgh, PA 15261, USA
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González-Hernández RJ, Jin K, Hernández-Chávez MJ, Díaz-Jiménez DF, Trujillo-Esquivel E, Clavijo-Giraldo DM, Tamez-Castrellón AK, Franco B, Gow NAR, Mora-Montes HM. Phosphomannosylation and the Functional Analysis of the Extended Candida albicans MNN4-Like Gene Family. Front Microbiol 2017; 8:2156. [PMID: 29163439 PMCID: PMC5681524 DOI: 10.3389/fmicb.2017.02156] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2017] [Accepted: 10/20/2017] [Indexed: 11/21/2022] Open
Abstract
Phosphomannosylation is a modification of cell wall proteins that occurs in some species of yeast-like organisms, including the human pathogen Candida albicans. These modified mannans confer a negative charge to the wall, which is important for the interactions with phagocytic cells of the immune systems and cationic antimicrobial peptides. In Saccharomyces cerevisiae, the synthesis of phosphomannan relies on two enzymes, the phosphomannosyltransferase Ktr6 and its positive regulator Mnn4. However, in C. albicans, at least three phosphomannosyltransferases, Mnn4, Mnt3 and Mnt5, participate in the addition of phosphomannan. In addition to MNN4, C. albicans has a MNN4-like gene family composed of seven other homologous members that have no known function. Here, using the classical mini-Ura-blaster approach and the new gene knockout CRISPR-Cas9 system for gene disruption, we generated mutants lacking single and multiple genes of the MNN4 family; and demonstrate that, although Mnn4 has a major impact on the phosphomannan content, MNN42 was also required for full protein phosphomannosylation. The reintroduction of MNN41, MNN42, MNN46, or MNN47 in a genetic background lacking MNN4 partially restored the phenotype associated with the mnn4Δ null mutant, suggesting that there is partial redundancy of function between some family members and that the dominant effect of MNN4 over other genes could be due to its relative abundance within the cell. We observed that additional copies of alleles number of any of the other family members, with the exception of MNN46, restored the phosphomannan content in cells lacking both MNT3 and MNT5. We, therefore, suggest that phosphomannosylation is achieved by three groups of proteins: [i] enzymes solely activated by Mnn4, [ii] enzymes activated by the dual action of Mnn4 and any of the products of other MNN4-like genes, with exception of MNN46, and [iii] activation of Mnt3 and Mnt5 by Mnn4 and Mnn46. Therefore, although the MNN4-like genes have the potential to functionally redundant with Mnn4, they apparently do not play a major role in cell wall mannosylation under most in vitro growth conditions. In addition, our phenotypic analyses indicate that several members of this gene family influence the ability of macrophages to phagocytose C. albicans cells.
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Affiliation(s)
| | - Kai Jin
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
- School of Life Sciences, Chongqing University, Chongqing, China
| | - Marco J. Hernández-Chávez
- División de Ciencias Naturales y Exactas, Departamento de Biología, Universidad de Guanajuato, Guanajuato, Mexico
| | - Diana F. Díaz-Jiménez
- Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional, Guanajuato, Mexico
| | - Elías Trujillo-Esquivel
- División de Ciencias Naturales y Exactas, Departamento de Biología, Universidad de Guanajuato, Guanajuato, Mexico
| | - Diana M. Clavijo-Giraldo
- División de Ciencias Naturales y Exactas, Departamento de Biología, Universidad de Guanajuato, Guanajuato, Mexico
| | - Alma K. Tamez-Castrellón
- División de Ciencias Naturales y Exactas, Departamento de Biología, Universidad de Guanajuato, Guanajuato, Mexico
| | - Bernardo Franco
- División de Ciencias Naturales y Exactas, Departamento de Biología, Universidad de Guanajuato, Guanajuato, Mexico
| | - Neil A. R. Gow
- Aberdeen Fungal Group, Institute of Medical Sciences, University of Aberdeen, Aberdeen, United Kingdom
| | - Héctor M. Mora-Montes
- División de Ciencias Naturales y Exactas, Departamento de Biología, Universidad de Guanajuato, Guanajuato, Mexico
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46
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Hernández NV, López-Ramírez LA, Díaz-Jiménez DF, Mellado-Mojica E, Martínez-Duncker I, López MG, Mora-Montes HM. Saccharomyces cerevisiae KTR4 , KTR5 and KTR7 encode mannosyltransferases differentially involved in the N - and O -linked glycosylation pathways. Res Microbiol 2017; 168:740-750. [DOI: 10.1016/j.resmic.2017.07.005] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 07/21/2017] [Accepted: 07/22/2017] [Indexed: 12/23/2022]
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47
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Base-modified GDP-mannose derivatives and their substrate activity towards a yeast mannosyltransferase. Carbohydr Res 2017; 452:91-96. [PMID: 29080432 DOI: 10.1016/j.carres.2017.09.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2017] [Revised: 09/18/2017] [Accepted: 09/19/2017] [Indexed: 01/17/2023]
Abstract
We have previously developed a new class of inhibitors and chemical probes for glycosyltransferases through base-modification of the sugar-nucleotide donor. The key feature of these donor analogues is the presence of an additional substituent at the nucleobase. To date, the application of this general concept has been limited to UDP-sugars and UDP-sugar-dependent glycosyltransferases. Herein, we report for the first time the application of our approach to a GDP-mannose-dependent mannosyltransferase. We have prepared four GDP-mannose derivatives with an additional substituent at either position 6 or 8 of the nucleobase. These donor analogues were recognised as donor substrates by the mannosyltransferase Kre2p from yeast, albeit with significantly lower turnover rates than the natural donor GDP-mannose. The presence of the additional substituent also redirected enzyme activity from glycosyl transfer to donor hydrolysis. Taken together, our results suggest that modification of the donor nucleobase is, in principle, a viable strategy for probe and inhibitor development against GDP-mannose-dependent GTs.
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48
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Alonso MF, Gow NAR, Erwig LP, Bain JM. Macrophage Migration Is Impaired within Candida albicans Biofilms. J Fungi (Basel) 2017; 3:jof3030031. [PMID: 29371549 PMCID: PMC5715939 DOI: 10.3390/jof3030031] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2017] [Revised: 06/14/2017] [Accepted: 06/16/2017] [Indexed: 11/16/2022] Open
Abstract
Candida albicans is an opportunistic fungal pathogen that infects immunocompromised patients. Infection control requires phagocytosis by innate immune cells, including macrophages. Migration towards, and subsequent recognition of, C. albicans fungal cell wall components by macrophages is critical for phagocytosis. Using live-cell imaging of phagocytosis, the macrophage cell line J774.1 showed enhanced movement in response to C. albicans cell wall mutants, particularly during the first 30 min, irrespective of the infection ratio. However, phagocyte migration was reduced up to 2-fold within a C. albicans biofilm compared to planktonic fungal cells. Biofilms formed from C. albicans glycosylation mutant cells also inhibited macrophage migration to a similar extent as wildtype Candida biofilms, suggesting that the physical structure of the biofilm, rather than polysaccharide matrix composition, may hamper phagocyte migration. These data illustrate differential macrophage migratory capacities, dependent upon the form of C. albicans encountered. Impaired migration of macrophages within a C. albicans biofilm may contribute to the recalcitrant nature of clinical infections in which biofilm formation occurs.
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Affiliation(s)
- Maria F Alonso
- Medical Research Council Centre for Medical Mycology, University of Aberdeen, Aberdeen AB25 2ZD, UK.
| | - Neil A R Gow
- Medical Research Council Centre for Medical Mycology, University of Aberdeen, Aberdeen AB25 2ZD, UK.
| | - Lars P Erwig
- Medical Research Council Centre for Medical Mycology, University of Aberdeen, Aberdeen AB25 2ZD, UK.
| | - Judith M Bain
- Medical Research Council Centre for Medical Mycology, University of Aberdeen, Aberdeen AB25 2ZD, UK.
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49
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Mukaremera L, Lee KK, Mora-Montes HM, Gow NAR. Candida albicans Yeast, Pseudohyphal, and Hyphal Morphogenesis Differentially Affects Immune Recognition. Front Immunol 2017. [PMID: 28638380 PMCID: PMC5461353 DOI: 10.3389/fimmu.2017.00629] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Candida albicans is a human opportunist pathogen that can grow as yeast, pseudohyphae, or true hyphae in vitro and in vivo, depending on environmental conditions. Reversible cellular morphogenesis is an important virulence factor that facilitates invasion of host tissues, escape from phagocytes, and dissemination in the blood stream. The innate immune system is the first line of defense against C. albicans infections and is influenced by recognition of wall components that vary in composition in different morphological forms. However, the relationship between cellular morphogenesis and immune recognition of this fungus is not fully understood. We therefore studied various vegetative cell types of C. albicans, singly and in combination, to assess the consequences of cellular morphogenesis on selected immune cytokine outputs from human monocytes. Hyphae stimulated proportionally lower levels of certain cytokines from monocytes per unit of cell surface area than yeast cells, but did not suppress cytokine response when copresented with yeast cells. Pseudohyphal cells induced intermediate cytokine responses. Yeast monomorphic mutants had elevated cytokine responses under conditions that otherwise supported filamentous growth and mutants of yeast and hyphal cells that were defective in cell wall mannosylation or lacking certain hypha-specific cell wall proteins could variably unmask or deplete the surface of immunostimulatory ligands. These observations underline the critical importance of C. albicans morphology and morphology-associated changes in the cell wall composition that affect both immune recognition and pathogenesis.
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Affiliation(s)
- Liliane Mukaremera
- Aberdeen Fungal Group, Institute of Medical Sciences, Foresterhill, University of Aberdeen, Aberdeen, United Kingdom.,Department of Microbiology and Immunology, Medical School, University of Minnesota, Minneapolis, MN, United States
| | - Keunsook K Lee
- Aberdeen Fungal Group, Institute of Medical Sciences, Foresterhill, University of Aberdeen, Aberdeen, United Kingdom
| | - Hector M Mora-Montes
- Departamento de Biología, División de Ciencias Naturales y Exactas, Universidad de Guanajuato, Guanajuato, Mexico
| | - Neil A R Gow
- Aberdeen Fungal Group, Institute of Medical Sciences, Foresterhill, University of Aberdeen, Aberdeen, United Kingdom
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50
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Hwang G, Liu Y, Kim D, Li Y, Krysan DJ, Koo H. Candida albicans mannans mediate Streptococcus mutans exoenzyme GtfB binding to modulate cross-kingdom biofilm development in vivo. PLoS Pathog 2017; 13:e1006407. [PMID: 28617874 PMCID: PMC5472321 DOI: 10.1371/journal.ppat.1006407] [Citation(s) in RCA: 126] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2017] [Accepted: 05/09/2017] [Indexed: 01/08/2023] Open
Abstract
Candida albicans is frequently detected with heavy infection by Streptococcus mutans in plaque-biofilms from children with early-childhood caries (ECC). This cross-kingdom biofilm contains an extensive matrix of extracellular α-glucans that is produced by an exoenzyme (GtfB) secreted by S. mutans. Here, we report that mannans located on the outer surface of C. albicans cell-wall mediates GtfB binding, enhancing glucan-matrix production and modulating bacterial-fungal association within biofilms formed in vivo. Using single-molecule atomic force microscopy, we determined that GtfB binds with remarkable affinity to mannans and to the C. albicans surface, forming a highly stable and strong bond (1-2 nN). However, GtfB binding properties to C. albicans was compromised in strains defective in O-mannan (pmt4ΔΔ) or N-mannan outer chain (och1ΔΔ). In particular, the binding strength of GtfB on och1ΔΔ strain was severely disrupted (>3-fold reduction vs. parental strain). In turn, the GtfB amount on the fungal surface was significantly reduced, and the ability of C. albicans mutant strains to develop mixed-species biofilms with S. mutans was impaired. This phenotype was independent of hyphae or established fungal-biofilm regulators (EFG1, BCR1). Notably, the mechanical stability of the defective biofilms was weakened, resulting in near complete biomass removal by shear forces. In addition, these in vitro findings were confirmed in vivo using a rodent biofilm model. Specifically, we observed that C. albicans och1ΔΔ was unable to form cross-kingdom biofilms on the tooth surface of rats co-infected with S. mutans. Likewise, co-infection with S. mutans defective in GtfB was also incapable of forming mixed-species biofilms. Taken together, the data support a mechanism whereby S. mutans-secreted GtfB binds to the mannan layer of C. albicans to promote extracellular matrix formation and their co-existence within biofilms. Enhanced understanding of GtfB-Candida interactions may provide new perspectives for devising effective therapies to disrupt this cross-kingdom relationship associated with an important childhood oral disease.
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Affiliation(s)
- Geelsu Hwang
- Biofilm Research Labs, Levy Center for Oral Health, Department of Orthodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States of America
| | - Yuan Liu
- Biofilm Research Labs, Levy Center for Oral Health, Department of Orthodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States of America
| | - Dongyeop Kim
- Biofilm Research Labs, Levy Center for Oral Health, Department of Orthodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States of America
| | - Yong Li
- Biofilm Research Labs, Levy Center for Oral Health, Department of Orthodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States of America
| | - Damian J. Krysan
- Department of Pediatrics, Infectious Diseases and Microbiology & Immunology, University of Rochester Medical Center, Rochester, NY, United States of America
| | - Hyun Koo
- Biofilm Research Labs, Levy Center for Oral Health, Department of Orthodontics, School of Dental Medicine, University of Pennsylvania, Philadelphia, PA, United States of America
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