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Zhou X, Hilk A, Solis NV, Pereira De Sa N, Hogan BM, Bierbaum TA, Del Poeta M, Filler SG, Burrack LS, Selmecki A. Erg251 has complex and pleiotropic effects on sterol composition, azole susceptibility, filamentation, and stress response phenotypes. PLoS Pathog 2024; 20:e1012389. [PMID: 39078851 PMCID: PMC11315318 DOI: 10.1371/journal.ppat.1012389] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 08/09/2024] [Accepted: 07/03/2024] [Indexed: 08/07/2024] Open
Abstract
Ergosterol is essential for fungal cell membrane integrity and growth, and numerous antifungal drugs target ergosterol. Inactivation or modification of ergosterol biosynthetic genes can lead to changes in antifungal drug susceptibility, filamentation and stress response. Here, we found that the ergosterol biosynthesis gene ERG251 is a hotspot for point mutations during adaptation to antifungal drug stress within two distinct genetic backgrounds of Candida albicans. Heterozygous point mutations led to single allele dysfunction of ERG251 and resulted in azole tolerance in both genetic backgrounds. This is the first known example of point mutations causing azole tolerance in C. albicans. Importantly, single allele dysfunction of ERG251 in combination with recurrent chromosome aneuploidies resulted in bona fide azole resistance. Homozygous deletions of ERG251 caused increased fitness in low concentrations of fluconazole and decreased fitness in rich medium, especially at low initial cell density. Homozygous deletions of ERG251 resulted in accumulation of ergosterol intermediates consistent with the fitness defect in rich medium. Dysfunction of ERG251, together with FLC exposure, resulted in decreased accumulation of the toxic sterol (14-ɑ-methylergosta-8,24(28)-dien-3β,6α-diol) and increased accumulation of non-toxic alternative sterols. The altered sterol composition of the ERG251 mutants had pleiotropic effects on transcription, filamentation, and stress responses including cell membrane, osmotic and oxidative stress. Interestingly, while dysfunction of ERG251 resulted in azole tolerance, it also led to transcriptional upregulation of ZRT2, a membrane-bound Zinc transporter, in the presence of FLC, and overexpression of ZRT2 is sufficient to increase azole tolerance in wild-type C. albicans. Finally, in a murine model of systemic infection, homozygous deletion of ERG251 resulted in decreased virulence while the heterozygous deletion mutants maintain their pathogenicity. Overall, this study demonstrates that single allele dysfunction of ERG251 is a recurrent and effective mechanism of acquired azole tolerance. We propose that altered sterol composition resulting from ERG251 dysfunction mediates azole tolerance as well as pleiotropic effects on stress response, filamentation and virulence.
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Affiliation(s)
- Xin Zhou
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Audrey Hilk
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, Minnesota, United States of America
| | - Norma V. Solis
- Division of Infectious Diseases, Lundquist Institute for Biomedical Innovation at Harbor UCLA Medical Center, Torrance, California, United States of America
| | - Nivea Pereira De Sa
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, New York, United States of America
| | - Bode M. Hogan
- Gustavus Adolphus College, Department of Biology, Saint Peter, Minnesota, USA
| | - Tessa A. Bierbaum
- Gustavus Adolphus College, Department of Biology, Saint Peter, Minnesota, USA
| | - Maurizio Del Poeta
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, New York, United States of America
- Division of Infectious Diseases, School of Medicine, Stony Brook University, Stony Brook, New York, United States of America
- Veterans Administration Medical Center, Northport, New York, United States of America
| | - Scott G. Filler
- Division of Infectious Diseases, Lundquist Institute for Biomedical Innovation at Harbor UCLA Medical Center, Torrance, California, United States of America
- David Geffen School of Medicine at UCLA, Los Angeles, California, United States of America
| | - Laura S. Burrack
- Gustavus Adolphus College, Department of Biology, Saint Peter, Minnesota, USA
| | - Anna Selmecki
- Department of Microbiology and Immunology, University of Minnesota, Minneapolis, Minnesota, United States of America
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Monjil MS, Kato H, Ota S, Matsuda K, Suzuki N, Tenhiro S, Tatsumi A, Pring S, Miura A, Camagna M, Suzuki T, Tanaka A, Terauchi R, Sato I, Chiba S, Kawakita K, Ojika M, Takemoto D. Two structurally different oomycete lipophilic microbe-associated molecular patterns induce distinctive plant immune responses. PLANT PHYSIOLOGY 2024:kiae255. [PMID: 38828881 DOI: 10.1093/plphys/kiae255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2023] [Accepted: 04/16/2024] [Indexed: 06/05/2024]
Abstract
Plants recognize a variety of external signals and induce appropriate mechanisms to increase their tolerance to biotic and abiotic stresses. Precise recognition of attacking pathogens and induction of effective resistance mechanisms are critical functions for plant survival. Some molecular patterns unique to a certain group of microbes, microbe-associated molecular patterns (MAMPs), are sensed by plant cells as nonself molecules via pattern recognition receptors. While MAMPs of bacterial and fungal origin have been identified, reports on oomycete MAMPs are relatively limited. This study aimed to identify MAMPs from an oomycete pathogen Phytophthora infestans, the causal agent of potato late blight. Using reactive oxygen species (ROS) production and phytoalexin production in potato (Solanum tuberosum) as markers, two structurally different groups of elicitors, namely ceramides and diacylglycerols, were identified. P. infestans ceramides (Pi-Cer A, B, and D) induced ROS production, while diacylglycerol (Pi-DAG A and B), containing eicosapentaenoic acid (EPA) as a substructure, induced phytoalexins production in potato. The molecular patterns in Pi-Cers and Pi-DAGs essential for defense induction were identified as 9-methyl-4,8-sphingadienine (9Me-Spd) and 5,8,11,14-tetraene-type fatty acid (5,8,11,14-TEFA), respectively. These structures are not found in plants, but in oomycetes and fungi, indicating that they are microbe molecular patterns recognized by plants. When Arabidopsis (Arabidopsis thaliana) was treated with Pi-Cer D and EPA, partially overlapping but different sets of genes were induced. Furthermore, expression of some genes is upregulated only after the simultaneous treatment with Pi-Cer D and EPA, indicating that plants combine the signals from simultaneously recognized MAMPs to adapt their defense response to pathogens.
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Affiliation(s)
- Mohammad Shahjahan Monjil
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan
- Department of Plant Pathology, Bangladesh Agricultural University, Mymensingh 2202, Bangladesh
| | - Hiroaki Kato
- Graduate School of Agriculture, Kyoto University, Muko, Kyoto 617-0001, Japan
| | - Satomi Ota
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - Kentaro Matsuda
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - Natsumi Suzuki
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - Shiho Tenhiro
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - Ayane Tatsumi
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - Sreynich Pring
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - Atsushi Miura
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - Maurizio Camagna
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - Takamasa Suzuki
- College of Bioscience and Biotechnology, Chubu University, Kasugai, Aichi 478-8501, Japan
| | - Aiko Tanaka
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - Ryohei Terauchi
- Graduate School of Agriculture, Kyoto University, Muko, Kyoto 617-0001, Japan
| | - Ikuo Sato
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - Sotaro Chiba
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - Kazuhito Kawakita
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - Makoto Ojika
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan
| | - Daigo Takemoto
- Graduate School of Bioagricultural Sciences, Nagoya University, Nagoya, Aichi 464-8601, Japan
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Xiong L, Pereira De Sa N, Zarnowski R, Huang MY, Mota Fernandes C, Lanni F, Andes DR, Del Poeta M, Mitchell AP. Biofilm-associated metabolism via ERG251 in Candida albicans. PLoS Pathog 2024; 20:e1012225. [PMID: 38739655 PMCID: PMC11115363 DOI: 10.1371/journal.ppat.1012225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2024] [Revised: 05/23/2024] [Accepted: 04/25/2024] [Indexed: 05/16/2024] Open
Abstract
Biofilm formation by the fungal pathogen Candida albicans is the basis for its ability to infect medical devices. The metabolic gene ERG251 has been identified as a target of biofilm transcriptional regulator Efg1, and here we report that ERG251 is required for biofilm formation but not conventional free-living planktonic growth. An erg251Δ/Δ mutation impairs biofilm formation in vitro and in an in vivo catheter infection model. In both in vitro and in vivo biofilm contexts, cell number is reduced and hyphal length is limited. To determine whether the mutant defect is in growth or some other aspect of biofilm development, we examined planktonic cell features in a biofilm-like environment, which was approximated with sealed unshaken cultures. Under those conditions, the erg251Δ/Δ mutation causes defects in growth and hyphal extension. Overexpression in the erg251Δ/Δ mutant of the paralog ERG25, which is normally expressed more weakly than ERG251, partially improves biofilm formation and biofilm hyphal content, as well as growth and hyphal extension in a biofilm-like environment. GC-MS analysis shows that the erg251Δ/Δ mutation causes a defect in ergosterol accumulation when cells are cultivated under biofilm-like conditions, but not under conventional planktonic conditions. Overexpression of ERG25 in the erg251Δ/Δ mutant causes some increase in ergosterol levels. Finally, the hypersensitivity of efg1Δ/Δ mutants to the ergosterol inhibitor fluconazole is reversed by ERG251 overexpression, arguing that reduced ERG251 expression contributes to this efg1Δ/Δ phenotype. Our results indicate that ERG251 is required for biofilm formation because its high expression levels are necessary for ergosterol synthesis in a biofilm-like environment.
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Affiliation(s)
- Liping Xiong
- Department of Microbiology, University of Georgia, Athens, Georgia, United States of America
| | - Nivea Pereira De Sa
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, New York, United States of America
| | - Robert Zarnowski
- Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Manning Y. Huang
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
| | - Caroline Mota Fernandes
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, New York, United States of America
| | - Frederick Lanni
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
| | - David R. Andes
- Department of Medical Microbiology and Immunology, University of Wisconsin, Madison, Wisconsin, United States of America
| | - Maurizio Del Poeta
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, New York, United States of America
| | - Aaron P. Mitchell
- Department of Microbiology, University of Georgia, Athens, Georgia, United States of America
- Department of Biological Sciences, Carnegie Mellon University, Pittsburgh, Pennsylvania, United States of America
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Kriegl L, Egger M, Boyer J, Hoenigl M, Krause R. New treatment options for critically important WHO fungal priority pathogens. Clin Microbiol Infect 2024:S1198-743X(24)00118-6. [PMID: 38461942 DOI: 10.1016/j.cmi.2024.03.006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2023] [Revised: 02/27/2024] [Accepted: 03/04/2024] [Indexed: 03/12/2024]
Abstract
BACKGROUND Yet often overlooked in public health discourse, fungal infections pose a crucial global disease burden associated with annual mortality rates approximately equal to tuberculosis and HIV. In response, the WHO published its first global priority list of fungal pathogens in 2022 assigning Aspergillus fumigatus, Candida albicans, Candida auris, and Cryptococcus neoformans to the critical group. OBJECTIVES This review provides succinct insights into novel antifungals in development, aiming to contribute valuable information and perspectives with a focus on recent clinical findings and new treatment approaches for critical members of the WHO fungal pathogen priority list. SOURCES PubMed literature search using 'Aspergillus fumigatus', 'Cryptococcus neoformans', 'Candida auris', and 'Candida albicans', along with the names of novel antifungal substances, including 'fosmanogepix', 'ibrexafungerp', 'opelconazole', 'oteseconazole', 'MAT2203', 'olorofim', and 'rezafungin' was conducted. CONTENT For each critical pathogen, current issues and global clinical data from recent trials are covered. The remarkable development of three new antifungal therapeutics recently receiving Food and Drug Administration approval (ibrexafungerp-June 2021, oteseconazole -April 2022, and rezafungin-March 2023) is outlined, with two more exciting new antifungal substances, namely, olorofim and fosmanogepix expecting approval within the next years. Ibrexafungerp, fosmanogepix, and rezafungin have additionally been granted orphan drug status by the European Medicines Agency in Europe (ibrexafungerp-November 2021, fosmanogepix-July 2022, and rezafungin-January 2024). IMPLICATIONS Although the limited number of targets and the emergence of resistance have posed challenges to antifungal treatment, new drugs such as ibrexafungerp, rezafungin, fosmanogepix, or olorofim have shown promising clinical efficacy. These drugs not only provide alternative options for invasive fungal infections but also alleviate treatment in outpatient settings. More clinical data, implementation of stewardship programmes, and surveillance, including utilization of drugs in agriculture, are necessary to prevent resistance development and to ensure the safety and efficacy of these new agents.
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Affiliation(s)
- Lisa Kriegl
- Division of Infectious Diseases, Department of Internal Medicine, ECMM Excellence Center for Clinical Mycology, Medical University of Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria
| | - Matthias Egger
- Division of Infectious Diseases, Department of Internal Medicine, ECMM Excellence Center for Clinical Mycology, Medical University of Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria
| | - Johannes Boyer
- Division of Infectious Diseases, Department of Internal Medicine, ECMM Excellence Center for Clinical Mycology, Medical University of Graz, Graz, Austria
| | - Martin Hoenigl
- Division of Infectious Diseases, Department of Internal Medicine, ECMM Excellence Center for Clinical Mycology, Medical University of Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria
| | - Robert Krause
- Division of Infectious Diseases, Department of Internal Medicine, ECMM Excellence Center for Clinical Mycology, Medical University of Graz, Graz, Austria; BioTechMed-Graz, Graz, Austria.
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Matos GS, Fernandes CM, Del Poeta M. Role of sphingolipids in the host-pathogen interaction. Biochim Biophys Acta Mol Cell Biol Lipids 2023; 1868:159384. [PMID: 37673393 PMCID: PMC11218662 DOI: 10.1016/j.bbalip.2023.159384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2023] [Revised: 06/21/2023] [Accepted: 07/05/2023] [Indexed: 09/08/2023]
Abstract
Fungal pathogens have been under the spotlight as their expanding geographic range combined with their potential harm to vulnerable populations turns them into increasingly threats to public health. Therefore, it is ultimately important to unveil the mechanisms associated with their infection process for further new treatment discovery. With this purpose, sphingolipid-based research has gained attention over the last years as these molecules have key properties that can regulate fungal pathogenicity. Here we discuss some of these properties as well as their role in fungal diseases, focusing on the subgroup of glycosphingolipids, as they represent promising molecules for drug discovery and for the development of fungal vaccines.
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Affiliation(s)
- Gabriel Soares Matos
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, NY, USA
| | | | - Maurizio Del Poeta
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, NY, USA; Institute of Chemical Biology and Drug Discovery (ICB&DD), Stony Brook, NY, USA; Division of Infectious Diseases, School of Medicine, Stony Brook University, Stony Brook, NY, USA; Veterans Administration Medical Center, Northport, NY, USA.
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6
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Ristow LC, Jezewski AJ, Chadwick BJ, Stamnes MA, Lin X, Krysan DJ. Cryptococcus neoformans adapts to the host environment through TOR-mediated remodeling of phospholipid asymmetry. Nat Commun 2023; 14:6587. [PMID: 37852972 PMCID: PMC10584969 DOI: 10.1038/s41467-023-42318-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Accepted: 10/06/2023] [Indexed: 10/20/2023] Open
Abstract
Cryptococcus spp. are environmental fungi that first must adapt to the host environment before they can cause life-threatening meningitis in immunocompromised patients. Host CO2 concentrations are 100-fold higher than the external environment and strains unable to grow at host CO2 concentrations are not pathogenic. Using a genetic screening and transcriptional profiling approach, we report that the TOR pathway is critical for C. neoformans adaptation to host CO2 partly through Ypk1-dependent remodeling of phosphatidylserine asymmetry at the plasma membrane. We also describe a C. neoformans ABC/PDR transporter (PDR9) that is highly expressed in CO2-sensitive environmental strains, suppresses CO2-induced phosphatidylserine/phospholipid remodeling, and increases susceptibility to host concentrations of CO2. Interestingly, regulation of plasma membrane lipid asymmetry by the TOR-Ypk1 axis is distinct in C. neoformans compared to S. cerevisiae. Finally, host CO2 concentrations suppress the C. neoformans pathways that respond to host temperature (Mpk1) and pH (Rim101), indicating that host adaptation requires a stringent balance among distinct stress responses.
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Affiliation(s)
- Laura C Ristow
- Department of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
| | - Andrew J Jezewski
- Department of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
| | | | - Mark A Stamnes
- Department of Molecular Physiology and Biophysics, Caver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA
| | - Xiaorong Lin
- Department of Plant Biology, University of Georgia, Athens, GA, 30602, USA
- Department of Microbiology, University of Georgia, Athens, GA, 30602, USA
| | - Damian J Krysan
- Department of Pediatrics, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA.
- Department of Molecular Physiology and Biophysics, Caver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA.
- Microbiology and Immunology, Carver College of Medicine, University of Iowa, Iowa City, IA, 52242, USA.
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7
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Usmani SA, Kumar M, Arya K, Ali B, Bhardwaj N, Gaur NA, Prasad R, Singh A. Beyond membrane components: uncovering the intriguing world of fungal sphingolipid synthesis and regulation. Res Microbiol 2023; 174:104087. [PMID: 37328042 DOI: 10.1016/j.resmic.2023.104087] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 06/06/2023] [Accepted: 06/07/2023] [Indexed: 06/18/2023]
Abstract
Sphingolipids (SLs) are essential to fungal survival and represent a major class of structural and signaling lipids. Unique SL structures and their biosynthetic enzymes in filamentous fungi make them an ideal drug target. Several studies have contributed towards the functional characterization of specific SL metabolism genes, which have been complemented by advanced lipidomics methods which allow accurate identification and quantification of lipid structures and pathway mapping. These studies have provided a better understanding of SL biosynthesis, degradation and regulation networks in filamentous fungi, which are discussed and elaborated here.
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Affiliation(s)
- Sana Akhtar Usmani
- Department of Biochemistry, University of Lucknow, Lucknow, Uttar Pradesh, 226024, India
| | - Mohit Kumar
- Amity Institute of Integrative Science and Health and Amity Institute of Biotechnology, Amity University Gurgaon, Haryana, India; International Centre for Genetic Engineering and Biotechnology, New Delhi 110067, India
| | - Khushboo Arya
- Department of Biochemistry, University of Lucknow, Lucknow, Uttar Pradesh, 226024, India
| | - Basharat Ali
- Amity Institute of Integrative Science and Health and Amity Institute of Biotechnology, Amity University Gurgaon, Haryana, India
| | - Nitin Bhardwaj
- Department of Zoology and Environmental Science, Gurukula Kangri Vishwavidyalaya, Haridwar, Uttarakhand 249404, India
| | - Naseem Akhtar Gaur
- International Centre for Genetic Engineering and Biotechnology, New Delhi 110067, India
| | - Rajendra Prasad
- Amity Institute of Integrative Science and Health and Amity Institute of Biotechnology, Amity University Gurgaon, Haryana, India
| | - Ashutosh Singh
- Department of Biochemistry, University of Lucknow, Lucknow, Uttar Pradesh, 226024, India.
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Shoma JF, Ernan B, Keiser G, Heiss C, Azadi P, Free SJ. Genetic Characterization of the Acidic and Neutral Glycosphingolipid Biosynthetic Pathways in Neurospora crassa. Microorganisms 2023; 11:2093. [PMID: 37630653 PMCID: PMC10457978 DOI: 10.3390/microorganisms11082093] [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: 07/27/2023] [Revised: 08/12/2023] [Accepted: 08/14/2023] [Indexed: 08/27/2023] Open
Abstract
Fungal glycosphingolipids (GSLs) are important membrane components which play a key role in vesicle trafficking. To assess the importance of GSLs in the fungal life cycle, we performed a mutant phenotypic study of the acidic and neutral GSL biosynthetic pathways in Neurospora crassa. GSL biosynthesis begins with two reactions leading up to the formation of dihydrosphingosine. The first of these reactions is catalyzed by serine palmitoyltransferase and generates 3-keto dihydrosphinganine. In N. crassa, this reaction is catalyzed by GSL-1 and GSL-2 and is required for viability. The second reaction is carried out by GSL-3, a 3-keto dihydrosphinoganine reductase to generate dihydrosphingosine, which is used for the synthesis of neutral and acidic GSLs. We found that deletion mutations in the acidic GSL pathway leading up to the formation of mannosylinositol-phosphoceramide are lethal, indicating that acidic GSLs are essential for viability in N. crassa. Once mannosylinositol-phosphoceramide is made, it is further modified by GSL-5, an inositol-phosphoceramide-B C26 hydroxylase, which adds a hydroxyl group to the amide-linked fatty acid. GSL-5 is not required for viability but gives a clear mutant phenotype affecting all stages of the life cycle. Our results show that the synthesis of mannosylinositol-phosphoceramide is required for viability and that the modification of the amide-linked fatty acid is important for acidic GSL functionality. We also examined the neutral GSL biosynthetic pathway and identified the presence of glucosylceramide. The deletion of neutral GSL biosynthetic genes affected hyphal morphology, vegetative growth rate, conidiation, and female development. Our results indicate that the synthesis of neutral GSLs is essential for normal growth and development of N. crassa.
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Affiliation(s)
- Jannatul F. Shoma
- Department of Biological Sciences, SUNY University at Buffalo, Cooke Hall Room 109, Buffalo, NY 14260, USA
| | - Ben Ernan
- Department of Biological Sciences, SUNY University at Buffalo, Cooke Hall Room 109, Buffalo, NY 14260, USA
| | - Griffin Keiser
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA (P.A.)
| | - Christian Heiss
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA (P.A.)
| | - Parastoo Azadi
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA (P.A.)
| | - Stephen J. Free
- Department of Biological Sciences, SUNY University at Buffalo, Cooke Hall Room 109, Buffalo, NY 14260, USA
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9
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Pereira de Sa N, Jayanetti K, Rendina D, Clement T, Soares Brauer V, Mota Fernandes C, Ojima I, Airola MV, Del Poeta M. Targeting Sterylglucosidase A to Treat Aspergillus fumigatus Infections. mBio 2023; 14:e0033923. [PMID: 36877042 PMCID: PMC10128061 DOI: 10.1128/mbio.00339-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2023] [Accepted: 02/10/2023] [Indexed: 03/07/2023] Open
Abstract
Invasive fungal infections are a leading cause of death in immunocompromised patients. Current therapies have several limitations, and innovative antifungal agents are critically needed. Previously, we identified the fungus-specific enzyme sterylglucosidase as essential for pathogenesis and virulence of Cryptococcus neoformans and Aspergillus fumigatus (Af) in murine models of mycoses. Here, we developed Af sterylglucosidase A (SglA) as a therapeutic target. We identified two selective inhibitors of SglA with distinct chemical scaffolds that bind in the active site of SglA. Both inhibitors induce sterylglucoside accumulation and delay filamentation in Af and increase survival in a murine model of pulmonary aspergillosis. Structure-activity relationship (SAR) studies identified a more potent derivative that enhances both in vitro phenotypes and in vivo survival. These findings support sterylglucosidase inhibition as a promising antifungal approach with broad-spectrum potential. IMPORTANCE Invasive fungal infections are a leading cause of death in immunocompromised patients. Aspergillus fumigatus is a fungus ubiquitously found in the environment that, upon inhalation, causes both acute and chronic illnesses in at-risk individuals. A. fumigatus is recognized as one of the critical fungal pathogens for which a substantive treatment breakthrough is urgently needed. Here, we studied a fungus-specific enzyme, sterylglucosidase A (SglA), as a therapeutic target. We identified selective inhibitors of SglA that induce accumulation of sterylglucosides and delay filamentation in A. fumigatus and increase survival in a murine model of pulmonary aspergillosis. We determined the structure of SglA, predicted the binding poses of these inhibitors through docking analysis, and identified a more efficacious derivative with a limited SAR study. These results open several exciting avenues for the research and development of a new class of antifungal agents targeting sterylglucosidases.
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Affiliation(s)
- Nivea Pereira de Sa
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, New York, USA
| | - Kalani Jayanetti
- Department of Chemistry, Stony Brook University, Stony Brook, New York, USA
| | - Dominick Rendina
- Department of Chemistry, Stony Brook University, Stony Brook, New York, USA
| | - Timothy Clement
- Department of Chemistry, Stony Brook University, Stony Brook, New York, USA
| | - Veronica Soares Brauer
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, New York, USA
| | - Caroline Mota Fernandes
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, New York, USA
| | - Iwao Ojima
- Department of Chemistry, Stony Brook University, Stony Brook, New York, USA
- Institute of Chemical Biology and Drug Discovery, Stony Brook, New York, USA
| | - Michael V. Airola
- Institute of Chemical Biology and Drug Discovery, Stony Brook, New York, USA
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, New York, USA
| | - Maurizio Del Poeta
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, New York, USA
- Institute of Chemical Biology and Drug Discovery, Stony Brook, New York, USA
- Division of Infectious Diseases, School of Medicine, Stony Brook University, Stony Brook, New York, USA
- Veterans Administration Medical Center, Northport, New York, USA
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Ishibashi Y. Functions and applications of glycolipid-hydrolyzing microbial glycosidases. Biosci Biotechnol Biochem 2022; 86:974-984. [PMID: 35675217 DOI: 10.1093/bbb/zbac089] [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: 04/04/2022] [Accepted: 05/29/2022] [Indexed: 11/13/2022]
Abstract
Glycolipids are important components of cell membranes in several organisms. The major glycolipids in mammals are glycosphingolipids (GSLs), which are composed of ceramides. In mammals, GSLs are degraded stepwise from the non-reducing end of the oligosaccharides via exo-type glycosidases. However, endoglycoceramidase (EGCase), an endo-type glycosidase found in actinomycetes, is a unique enzyme that directly acts on the glycosidic linkage between oligosaccharides and ceramides to generate intact oligosaccharides and ceramides. Three molecular species of EGCase, namely EGCase I, EGCase II, and endogalactosylceramidase, have been identified based on their substrate specificity. EGCrP1 and EGCrP2, which are homologs of EGCase in pathogenic fungi, were identified as the first fungal glucosylceramide- and sterylglucoside-hydrolyzing glycosidases, respectively. These enzymes are promising targets for antifungal drugs against pathogenic fungi. This review describes the functions and properties of these microbial glycolipid-degrading enzymes, the molecular basis of their differential substrate specificity, and their applications.
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Affiliation(s)
- Yohei Ishibashi
- Department of Bioscience and Biotechnology, Graduate School of Bioresource and Bioenvironmental Sciences, Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka, Japan
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11
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Phenotype to genotype in Neurospora crassa: Association of the scumbo phenotype with mutations in the gene encoding ceramide C9-methyltransferase. CURRENT RESEARCH IN MICROBIAL SCIENCES 2022; 3:100117. [PMID: 35909622 PMCID: PMC9325734 DOI: 10.1016/j.crmicr.2022.100117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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12
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Structure and inhibition of Cryptococcus neoformans sterylglucosidase to develop antifungal agents. Nat Commun 2021; 12:5885. [PMID: 34620873 PMCID: PMC8497620 DOI: 10.1038/s41467-021-26163-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 09/21/2021] [Indexed: 12/02/2022] Open
Abstract
Pathogenic fungi exhibit a heavy burden on medical care and new therapies are needed. Here, we develop the fungal specific enzyme sterylglucosidase 1 (Sgl1) as a therapeutic target. Sgl1 converts the immunomodulatory glycolipid ergosterol 3β-D-glucoside to ergosterol and glucose. Previously, we found that genetic deletion of Sgl1 in the pathogenic fungus Cryptococcus neoformans (Cn) results in ergosterol 3β-D-glucoside accumulation, renders Cn non-pathogenic, and immunizes mice against secondary infections by wild-type Cn, even in condition of CD4+ T cell deficiency. Here, we disclose two distinct chemical classes that inhibit Sgl1 function in vitro and in Cn cells. Pharmacological inhibition of Sgl1 phenocopies a growth defect of the Cn Δsgl1 mutant and prevents dissemination of wild-type Cn to the brain in a mouse model of infection. Crystal structures of Sgl1 alone and with inhibitors explain Sgl1’s substrate specificity and enable the rational design of antifungal agents targeting Sgl1. Sterylglucosidase 1 (Sgl1) is a virulence factor in Cryptococcus neoformans that modulates fungal pathogenesis and host response. Here, the authors characterize Sgl1 structurally, identify Sgl1 inhibitors, and demonstrate Sgl1 inhibition has efficacy in mouse models of infection.
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Wang J, Chen YL, Li YK, Chen DK, He JF, Yao N. Functions of Sphingolipids in Pathogenesis During Host-Pathogen Interactions. Front Microbiol 2021; 12:701041. [PMID: 34408731 PMCID: PMC8366399 DOI: 10.3389/fmicb.2021.701041] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Accepted: 06/21/2021] [Indexed: 12/23/2022] Open
Abstract
Sphingolipids are a class of membrane lipids that serve as vital structural and signaling bioactive molecules in organisms ranging from yeast to animals. Recent studies have emphasized the importance of sphingolipids as signaling molecules in the development and pathogenicity of microbial pathogens including bacteria, fungi, and viruses. In particular, sphingolipids play key roles in regulating the delicate balance between microbes and hosts during microbial pathogenesis. Some pathogens, such as bacteria and viruses, harness host sphingolipids to promote development and infection, whereas sphingolipids from both the host and pathogen are involved in fungus-host interactions. Moreover, a regulatory role for sphingolipids has been described, but their effects on host physiology and metabolism remain to be elucidated. Here, we summarize the current state of knowledge about the roles of sphingolipids in pathogenesis and interactions with host factors, including how sphingolipids modify pathogen and host metabolism with a focus on pathogenesis regulators and relevant metabolic enzymes. In addition, we discuss emerging perspectives on targeting sphingolipids that function in host-microbe interactions as new therapeutic strategies for infectious diseases.
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Affiliation(s)
- Jian Wang
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resource, School of Agriculture, Sun Yat-sen University, Guangzhou, China
| | - Yi-Li Chen
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resource, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Yong-Kang Li
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resource, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Ding-Kang Chen
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resource, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
| | - Jia-Fan He
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resource, School of Agriculture, Sun Yat-sen University, Guangzhou, China
| | - Nan Yao
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resource, School of Agriculture, Sun Yat-sen University, Guangzhou, China
- State Key Laboratory of Biocontrol, Guangdong Provincial Key Laboratory of Plant Resource, School of Life Sciences, Sun Yat-sen University, Guangzhou, China
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14
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Jiang C, Ge J, He B, Zeng B. Glycosphingolipids in Filamentous Fungi: Biological Roles and Potential Applications in Cosmetics and Health Foods. Front Microbiol 2021; 12:690211. [PMID: 34367090 PMCID: PMC8341767 DOI: 10.3389/fmicb.2021.690211] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2021] [Accepted: 06/28/2021] [Indexed: 11/13/2022] Open
Abstract
Filamentous fungi are a group of economically important fungi used in the production of fermented foods, industrial enzymes, and secondary metabolites. Glycosphingolipids (GSLs) as constituents of lipid rafts are involved in growth, differentiation, and response to environment stress in filamentous fungi. In addition to these key roles, GSLs are also important in the barrier function of skin to retain moisture as a moisturizing ingredient in cosmetics or health products for their strong biological activity as a functional component. GSLs found in filamentous fungi are divided in two major classes: neutral GSLs (glycosylceramides), glucosylceramides (GlcCers), and/or galactosylceramides (GalCers) and acidic GSLs, mannosylinositol phosphorylceramide (MIPC) and mannosyldiinositol phosphorylceramide [M(IP)2C]. Glycosylceramides are one of the abundant GSLs in Aspergillus and known to improve skin-barrier function and prevent intestinal impairment as a prebiotic. Some filamentous fungi of Aspergillus spp., synthesizing both GlcCer and GalCer, would be an amenable source to exploit glycosylceramides that wildly adding in cosmetics as moisturizing ingredients or health food as dietary supplements. In this minireview, the types, structures, and biosynthetic pathways of GSLs in filamentous fungi, and the relevance of GSLs in fungal growth, spore formation, and environmental stress response are explained. Furthermore, the advantage, potential development, and application of GlcCer and GalCer from filamentous fungi Aspergillus spp. are also investigate based on the use of plant GlcCer in health foods and cosmetics.
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Affiliation(s)
- Chunmiao Jiang
- Jiangxi Key Laboratory of Bioprocess Engineering and Co-Innovation Center for In-Vitro Diagnostic Reagents and Devices of Jiangxi Province, College of Life Sciences, Jiangxi Science and Technology Normal University, Nanchang, China
| | - Jinxin Ge
- Jiangxi Key Laboratory of Bioprocess Engineering and Co-Innovation Center for In-Vitro Diagnostic Reagents and Devices of Jiangxi Province, College of Life Sciences, Jiangxi Science and Technology Normal University, Nanchang, China
| | - Bin He
- Jiangxi Key Laboratory of Bioprocess Engineering and Co-Innovation Center for In-Vitro Diagnostic Reagents and Devices of Jiangxi Province, College of Life Sciences, Jiangxi Science and Technology Normal University, Nanchang, China
| | - Bin Zeng
- Jiangxi Key Laboratory of Bioprocess Engineering and Co-Innovation Center for In-Vitro Diagnostic Reagents and Devices of Jiangxi Province, College of Life Sciences, Jiangxi Science and Technology Normal University, Nanchang, China.,College of Pharmacy, Shenzhen Technology University, Shenzhen, China
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15
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Peláez-Jaramillo CA, Jiménez-Alzate MDP, Araque-Marin P, Hung CY, Castro-Lopez N, Cole GT. Lipid Secretion by Parasitic Cells of Coccidioides Contributes to Disseminated Disease. Front Cell Infect Microbiol 2021; 11:592826. [PMID: 34055661 PMCID: PMC8155295 DOI: 10.3389/fcimb.2021.592826] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Accepted: 04/14/2021] [Indexed: 11/13/2022] Open
Abstract
Coccidioides is a soil-borne fungal pathogen and causative agent of a human respiratory disease (coccidioidomycosis) endemic to semi-desert regions of southwestern United States, Mexico, Central and South America. Aerosolized arthroconidia inhaled by the mammalian host first undergo conversion to large parasitic cells (spherules, 80-100 μm diameter) followed by endosporulation, a process by which the contents of spherules give rise to multiple endospores. The latter are released upon rupture of the maternal spherules and establish new foci of lung infection. A novel feature of spherule maturation prior to endosporulation is the secretion of a lipid-rich, membranous cell surface layer shed in vivo during growth of the parasitic cells and secretion into liquid culture medium during in vitro growth. Chemical analysis of the culture derived spherule outer wall (SOW) fraction showed that it is composed largely of phospholipids and is enriched with saturated fatty acids, including myristic, palmitic, elaidic, oleic, and stearic acid. NMR revealed the presence of monosaccharide- and disaccharide-linked acylglycerols and sphingolipids. The major sphingolipid components are sphingosine and ceramide. Primary neutrophils derived from healthy C57BL/6 and DBA/2 mice incubated with SOW lipids revealed a significant reduction in fungicidal activity against viable Coccidioides arthroconidia compared to incubation of neutrophils with arthroconidia alone. Host cell exposure to SOW lipids had no effect on neutrophil viability. Furthermore, C57BL/6 mice that were challenged subcutaneously with Coccidioides arthroconidia in the presence of the isolated SOW fraction developed disseminated disease, while control mice challenged with arthroconidia alone by the same route showed no dissemination of infection. We hypothesize that SOW lipids contribute to suppression of inflammatory response to Coccidioides infection. Studies are underway to characterize the immunosuppressive mechanism(s) of SOW lipids.
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Affiliation(s)
- Carlos Alberto Peláez-Jaramillo
- The Biology Department and South Texas Center for Emerging Infectious Diseases, University of Texas at San Antonio, San Antonio, TX, United States.,Grupo Interdisciplinario de Estudios Moleculares, Chemistry Institute, Faculty of Natural and Exact Sciencess, Medellín, Antioquia, Colombia.,Grupo Micología Médica, Microbiology and Parasitology Department, School of Medicine, Universidad de Antioquia, Medellín, Antioquia, Colombia
| | - Maria Del Pilar Jiménez-Alzate
- The Biology Department and South Texas Center for Emerging Infectious Diseases, University of Texas at San Antonio, San Antonio, TX, United States.,Grupo Interdisciplinario de Estudios Moleculares, Chemistry Institute, Faculty of Natural and Exact Sciencess, Medellín, Antioquia, Colombia
| | - Pedronel Araque-Marin
- School of Life Sciences, EIA University (Universidad Escuela de Ingenieros de Antioquia), Envigado, Antioquia, Colombia
| | - Chiung-Yu Hung
- The Biology Department and South Texas Center for Emerging Infectious Diseases, University of Texas at San Antonio, San Antonio, TX, United States
| | - Natalia Castro-Lopez
- The Biology Department and South Texas Center for Emerging Infectious Diseases, University of Texas at San Antonio, San Antonio, TX, United States
| | - Garry T Cole
- The Biology Department and South Texas Center for Emerging Infectious Diseases, University of Texas at San Antonio, San Antonio, TX, United States
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16
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Treatment strategies for cryptococcal infection: challenges, advances and future outlook. Nat Rev Microbiol 2021; 19:454-466. [PMID: 33558691 PMCID: PMC7868659 DOI: 10.1038/s41579-021-00511-0] [Citation(s) in RCA: 135] [Impact Index Per Article: 45.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/07/2021] [Indexed: 01/31/2023]
Abstract
Cryptococcus spp., in particular Cryptococcus neoformans and Cryptococcus gattii, have an enormous impact on human health worldwide. The global burden of cryptococcal meningitis is almost a quarter of a million cases and 181,000 deaths annually, with mortality rates of 100% if infections remain untreated. Despite these alarming statistics, treatment options for cryptococcosis remain limited, with only three major classes of drugs approved for clinical use. Exacerbating the public health burden is the fact that the only new class of antifungal drugs developed in decades, the echinocandins, displays negligible antifungal activity against Cryptococcus spp., and the efficacy of the remaining therapeutics is hampered by host toxicity and pathogen resistance. Here, we describe the current arsenal of antifungal agents and the treatment strategies employed to manage cryptococcal disease. We further elaborate on the recent advances in our understanding of the intrinsic and adaptive resistance mechanisms that are utilized by Cryptococcus spp. to evade therapeutic treatments. Finally, we review potential therapeutic strategies, including combination therapy, the targeting of virulence traits, impairing stress response pathways and modulating host immunity, to effectively treat infections caused by Cryptococcus spp. Overall, understanding of the mechanisms that regulate anti-cryptococcal drug resistance, coupled with advances in genomics technologies and high-throughput screening methodologies, will catalyse innovation and accelerate antifungal drug discovery.
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17
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Saromi K, England P, Tang W, Kostrzewa M, Corran A, Woscholski R, Larrouy-Maumus G. Rapid glycosyl-inositol-phospho-ceramide fingerprint from filamentous fungal pathogens using the MALDI Biotyper Sirius system. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2020; 34:e8904. [PMID: 32700347 DOI: 10.1002/rcm.8904] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 07/19/2020] [Accepted: 07/19/2020] [Indexed: 06/11/2023]
Abstract
RATIONALE Glycosyl-inositol-phospho-ceramides (GIPCs) or glycosylphosphatidylinositol-anchored fungal polysaccharides are known to be major lipids in plant and fungal plasma membranes and to play an important role in stress adaption. However, their analysis remains challenging due to the several steps involved for their extractions and purifications prior to mass spectrometric analysis. To address this challenge, we developed a rapid and sensitive method to identify GIPCs from the four common fungal plant pathogens Botrytis cinerea, Fusarium graminearium, Neurospora crassa and Ustilago maydis. METHODS Fungal plant pathogens were cultured, harvested, heat-inactivated and washed three times with double-distilled water. Intact fungi were deposited on a matrix-assisted laser desorption ionization (MALDI) target plate, mixed with the matrix consisting of a 9:1 mixture of 2,5-dihydroxybenzoic acid and 2-hydroxy-5-methoxybenzoic acid solubilized at 10 mg/mL in chloroform-methanol (9:1 v/v) and analyzed using a Bruker MALDI Biotyper Sirius system in the linear negative ion mode. Mass spectra were acquired from m/z 700 to 2000. RESULTS MALDI time-of-flight (TOF) mass spectrometric analysis of cultured fungi showed clear signature of GIPCs in B. cinerea, F. graminearium, N. crassa and U. maydis. CONCLUSIONS We have demonstrated that routine MALDI-TOF in the linear negative ion mode combined with an apolar solvent system to solubilize the matrix is applicable to the detection of filamentous fungal GIPCs.
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Affiliation(s)
- Kofo Saromi
- Department of Chemistry, Faculty of Natural Sciences and Institute of Chemical Biology (ICB), Imperial College London, South Kensington Campus, London, SW7 2AZ, UK
| | - Philippa England
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, SW7 2AZ, UK
| | - Wenhao Tang
- Department of Mathematics, Imperial College London, London, SW7 2AZ, UK
| | | | - Andy Corran
- Syngenta Group, Bioscience, Jealott's Hill Research Station, Bracknell RG42 6EY, UK
| | - Rudiger Woscholski
- Department of Chemistry, Faculty of Natural Sciences and Institute of Chemical Biology (ICB), Imperial College London, South Kensington Campus, London, SW7 2AZ, UK
| | - Gerald Larrouy-Maumus
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, SW7 2AZ, UK
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Santos FC, Marquês JT, Bento‐Oliveira A, Almeida RF. Sphingolipid‐enriched domains in fungi. FEBS Lett 2020; 594:3698-3718. [DOI: 10.1002/1873-3468.13986] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 09/21/2020] [Accepted: 10/13/2020] [Indexed: 12/11/2022]
Affiliation(s)
- Filipa C. Santos
- Centro de Química Estrutural Faculdade de Ciências, Universidade de Lisboa Campo Grande Portugal
| | - Joaquim T. Marquês
- Centro de Química Estrutural Faculdade de Ciências, Universidade de Lisboa Campo Grande Portugal
| | - Andreia Bento‐Oliveira
- Centro de Química Estrutural Faculdade de Ciências, Universidade de Lisboa Campo Grande Portugal
| | - Rodrigo F.M. Almeida
- Centro de Química Estrutural Faculdade de Ciências, Universidade de Lisboa Campo Grande Portugal
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Randez-Gil F, Bojunga L, Estruch F, Winderickx J, Del Poeta M, Prieto JA. Sphingolipids and Inositol Phosphates Regulate the Tau Protein Phosphorylation Status in Humanized Yeast. Front Cell Dev Biol 2020; 8:592159. [PMID: 33282871 PMCID: PMC7705114 DOI: 10.3389/fcell.2020.592159] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2020] [Accepted: 10/21/2020] [Indexed: 01/08/2023] Open
Abstract
Hyperphosphorylation of protein tau is a hallmark of Alzheimer's disease (AD). Changes in energy and lipid metabolism have been correlated with the late onset of this neurological disorder. However, it is uncertain if metabolic dysregulation is a consequence of AD or one of the initiating factors of AD pathophysiology. Also, it is unclear whether variations in lipid metabolism regulate the phosphorylation state of tau. Here, we show that in humanized yeast, tau hyperphosphorylation is stimulated by glucose starvation in coincidence with the downregulation of Pho85, the yeast ortholog of CDK5. Changes in inositol phosphate (IP) signaling, which has a central role in energy metabolism, altered tau phosphorylation. Lack of inositol hexakisphosphate kinases Kcs1 and Vip1 (IP6 and IP7 kinases in mammals) increased tau hyperphosphorylation. Similar effects were found by mutation of IPK2 (inositol polyphosphate multikinase), or PLC1, the yeast phospholipase C gene. These effects may be explained by IP-mediated regulation of Pho85. Indeed, this appeared to be the case for plc1, ipk2, and kcs1. However, the effects of Vip1 on tau phosphorylation were independent of the presence of Pho85, suggesting additional mechanisms. Interestingly, kcs1 and vip1 strains, like pho85, displayed dysregulated sphingolipid (SL) metabolism. Moreover, genetic and pharmacological inhibition of SL biosynthesis stimulated the appearance of hyperphosphorylated forms of tau, while increased flux through the pathway reduced its abundance. Finally, we demonstrated that Sit4, the yeast ortholog of human PP2A protein phosphatase, is a downstream effector of SL signaling in mediating the tau phosphorylation state. Altogether, our results add new knowledge on the molecular effectors involved in tauopathies and identify new targets for pharmacological intervention.
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Affiliation(s)
- Francisca Randez-Gil
- Department of Biotechnology, Instituto de Agroquímica y Tecnología de los Alimentos, Consejo Superior de Investigaciones Científicas, Valencia, Spain
| | - Lino Bojunga
- Department of Biotechnology, Instituto de Agroquímica y Tecnología de los Alimentos, Consejo Superior de Investigaciones Científicas, Valencia, Spain
| | - Francisco Estruch
- Departament of Biochemistry and Molecular Biology, Universitat de València, Valencia, Spain
| | | | - Maurizio Del Poeta
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY, United States
- Veterans Administration Medical Center, Northport, NY, United States
| | - Jose A. Prieto
- Department of Biotechnology, Instituto de Agroquímica y Tecnología de los Alimentos, Consejo Superior de Investigaciones Científicas, Valencia, Spain
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Fernandes CM, Poeta MD. Fungal sphingolipids: role in the regulation of virulence and potential as targets for future antifungal therapies. Expert Rev Anti Infect Ther 2020; 18:1083-1092. [PMID: 32673125 PMCID: PMC7657966 DOI: 10.1080/14787210.2020.1792288] [Citation(s) in RCA: 24] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Accepted: 07/02/2020] [Indexed: 12/17/2022]
Abstract
INTRODUCTION The antifungal therapy currently available includes three major classes of drugs: polyenes, azoles and echinocandins. However, the clinical use of these compounds faces several challenges: while polyenes are toxic to the host, antifungal resistance to azoles and echinocandins has been reported. AREAS COVERED Fungal sphingolipids (SL) play a pivotal role in growth, morphogenesis and virulence. In addition, fungi possess unique enzymes involved in SL synthesis, leading to the production of lipids which are absent or differ structurally from the mammalian counterparts. In this review, we address the enzymatic reactions involved in the SL synthesis and their relevance to the fungal pathogenesis, highlighting their potential as targets for novel drugs and the inhibitors described so far. EXPERT OPINION The pharmacological inhibition of fungal serine palmitoyltransferase depends on the development of specific drugs, as myriocin also targets the mammalian enzyme. Inhibitors of ceramide synthase might constitute potent antifungals, by depleting the pool of complex SL and leading to the accumulation of the toxic intermediates. Acylhydrazones and aureobasidin A, which inhibit GlcCer and IPC synthesis, are not toxic to the host and effectively treat invasive mycoses, emerging as promising new classes of antifungal drugs.
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Affiliation(s)
| | - Maurizio Del Poeta
- Department of Microbiology and Immunology, Stony Brook University, NY, USA
- Division of Infectious Diseases, School of Medicine, Stony Brook University, NY, USA
- Veterans Administration Medical Center, Northport, NY, USA
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Rollin-Pinheiro R, Xisto MIDDS, Rochetti VP, Barreto-Bergter E. Scedosporium Cell Wall: From Carbohydrate-Containing Structures to Host-Pathogen Interactions. Mycopathologia 2020; 185:931-946. [PMID: 32990888 DOI: 10.1007/s11046-020-00480-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2020] [Accepted: 07/20/2020] [Indexed: 12/16/2022]
Abstract
Scedosporium species are filamentous fungi usually found in sewage and soil from human-impacted areas. They cause a wide range of diseases in humans, from superficial infections, such as mycetoma, to invasive and disseminated cases, especially associated in immunocompromised patients. Scedosporium species are also related to lung colonization in individuals presenting cystic fibrosis and are considered one of the most frequent fungal pathogens associated to this pathology. Scedosporium cell wall contains glycosylated molecules involved in important biological events related to virulence and pathogenicity and represents a significant source of antigens. Polysaccharides, peptidopolysaccharides, O-linked oligosaccharides and glycosphingolipids have been identified on the Scedosporium surface. Their primary structures were determined based on a combination of techniques including gas chromatography, ESI-MS, and 1H and 13C nuclear magnetic resonance. Peptidorhamnnomannans are common cell wall components among Scedosporium species. Comparing different species, minor structural differences in the carbohydrate portions were detected which could be useful to understand variations in virulence observed among the species. N- and O-linked peptidorhamnomannans are major pathogen-associated molecular patterns and, along with α-glucans, play important roles in triggering host innate immunity. Glycosphingolipids, such as glucosylceramides, have highly conserved structures in Scedosporium species and are crucial for fungal growth and virulence. The present review presents current knowledge on structural and functional aspects of Scedosporium glycoconjugates that are relevant for understanding pathogenicity mechanisms and could contribute to the design of new agents capable of inhibiting growth and differentiation of Scedosporium species. Other cell components such as melanin and ectophosphatases will be also included.
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Affiliation(s)
- Rodrigo Rollin-Pinheiro
- Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, 21941-902, Brazil
| | - Mariana Ingrid Dutra da Silva Xisto
- Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, 21941-902, Brazil
| | - Victor Pereira Rochetti
- Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, 21941-902, Brazil
| | - Eliana Barreto-Bergter
- Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, Universidade Federal Do Rio de Janeiro, Rio de Janeiro, 21941-902, Brazil.
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McEvoy K, Normile TG, Poeta MD. Antifungal Drug Development: Targeting the Fungal Sphingolipid Pathway. J Fungi (Basel) 2020; 6:jof6030142. [PMID: 32825250 PMCID: PMC7559796 DOI: 10.3390/jof6030142] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2020] [Revised: 08/13/2020] [Accepted: 08/18/2020] [Indexed: 02/06/2023] Open
Abstract
Fungal infections are becoming more prevalent and problematic due to the continual rise of immune deficient patients as well as the progressive development of drug resistance towards currently available antifungal drugs. There has been a significant increase in the development of antifungal compounds with a similar mechanism of action of current drugs. In contrast, there has been very little progress in developing compounds inhibiting totally new fungal targets or/and fungal pathways. This review focuses on novel compounds recently discovered to target the fungal sphingolipids and their metabolizing enzymes.
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Affiliation(s)
- Kyle McEvoy
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, NY 11794, USA; (K.M.); (T.G.N.)
| | - Tyler G. Normile
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, NY 11794, USA; (K.M.); (T.G.N.)
| | - Maurizio Del Poeta
- Department of Microbiology and Immunology, Stony Brook University, Stony Brook, NY 11794, USA; (K.M.); (T.G.N.)
- Division of Infectious Diseases, School of Medicine, Stony Brook University, Stony Brook, NY 11794, USA
- Veterans Administration Medical Center, Northport, NY 11768, USA
- Correspondence: ; Tel.: +1-631-632-4024
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Song J, Liu X, Li R. Sphingolipids: Regulators of azole drug resistance and fungal pathogenicity. Mol Microbiol 2020; 114:891-905. [PMID: 32767804 DOI: 10.1111/mmi.14586] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Revised: 07/29/2020] [Accepted: 08/02/2020] [Indexed: 12/14/2022]
Abstract
In recent years, the role of sphingolipids in pathogenic fungi, in terms of pathogenicity and resistance to azole drugs, has been a rapidly growing field. This review describes evidence about the roles of sphingolipids in azole resistance and fungal virulence. Sphingolipids can serve as signaling molecules that contribute to azole resistance through modulation of the expression of drug efflux pumps. They also contribute to azole resistance by participating in various microbial pathways such as the unfolded protein response (UPR), pH-responsive Rim pathway, and pleiotropic drug resistance (PDR) pathway. In addition, sphingolipid signaling and eisosomes also coordinately regulate sphingolipid biosynthesis in response to azole-induced membrane stress. Sphingolipids are important for fungal virulence, playing roles during growth in hosts under stressful conditions, maintenance of cell wall integrity, biofilm formation, and production of various virulence factors. Finally, we discuss the possibility of exploiting fungal sphingolipids for the development of new therapeutic strategies to treat infections caused by pathogenic fungi.
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Affiliation(s)
- Jinxing Song
- The Key Laboratory of Biotechnology for Medicinal Plants of Jiangsu Province and School of Life Science, Jiangsu Normal University, Xuzhou, PR China
| | - Xiao Liu
- The Key Laboratory of Biotechnology for Medicinal Plants of Jiangsu Province and School of Life Science, Jiangsu Normal University, Xuzhou, PR China
| | - Rongpeng Li
- The Key Laboratory of Biotechnology for Medicinal Plants of Jiangsu Province and School of Life Science, Jiangsu Normal University, Xuzhou, PR China
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24
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Prieto JA, Estruch F, Córcoles-Sáez I, Del Poeta M, Rieger R, Stenzel I, Randez-Gil F. Pho85 and PI(4,5)P 2 regulate different lipid metabolic pathways in response to cold. Biochim Biophys Acta Mol Cell Biol Lipids 2020; 1865:158557. [PMID: 31678512 PMCID: PMC7254492 DOI: 10.1016/j.bbalip.2019.158557] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Revised: 10/25/2019] [Accepted: 10/26/2019] [Indexed: 12/11/2022]
Abstract
Lipid homeostasis allows cells to adjust membrane biophysical properties in response to changes in environmental conditions. In the yeast Saccharomyces cerevisiae, a downward shift in temperature from an optimal reduces membrane fluidity, which triggers a lipid remodeling of the plasma membrane. How changes in membrane fluidity are perceived, and how the abundance and composition of different lipid classes is properly balanced, remain largely unknown. Here, we show that the levels of phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2], the most abundant plasma membrane phosphoinositide, drop rapidly in response to a downward shift in temperature. This change triggers a signaling cascade transmitted to cytosolic diphosphoinositol phosphate derivatives, among them 5-PP-IP4 and 1-IP7, that exert regulatory functions on genes involved in the inositol and phospholipids (PLs) metabolism, and inhibit the activity of the protein kinase Pho85. Consistent with this, cold exposure triggers a specific program of neutral lipids and PLs changes. Furthermore, we identified Pho85 as playing a key role in controlling the synthesis of long-chain bases (LCBs) via the Ypk1-Orm2 regulatory circuit. We conclude that Pho85 orchestrates a coordinated response of lipid metabolic pathways that ensure yeast thermal adaptation.
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Affiliation(s)
- Jose A Prieto
- Department of Biotechnology, Instituto de Agroquímica y Tecnología de los Alimentos, Consejo Superior de Investigaciones Científicas, Avda. Agustín Escardino, 7, 46980 Paterna, Valencia, Spain
| | - Francisco Estruch
- Departament of Biochemistry and Molecular Biology, Universitat de València, Dr. Moliner 50, Burjassot 46100, Spain
| | - Isaac Córcoles-Sáez
- Department of Biotechnology, Instituto de Agroquímica y Tecnología de los Alimentos, Consejo Superior de Investigaciones Científicas, Avda. Agustín Escardino, 7, 46980 Paterna, Valencia, Spain
| | - Maurizio Del Poeta
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY, United States of America; Veterans Administration Medical Center, Northport, NY, United States of America
| | - Robert Rieger
- Proteomics Center, Stony Brook University, Stony Brook, NY, United States of America
| | - Irene Stenzel
- Department of Cellular Biochemistry, Institute of Biochemistry and Biotechnology, Martin Luther University Halle-Wittenberg, 06120 Halle (Saale), Germany
| | - Francisca Randez-Gil
- Department of Biotechnology, Instituto de Agroquímica y Tecnología de los Alimentos, Consejo Superior de Investigaciones Científicas, Avda. Agustín Escardino, 7, 46980 Paterna, Valencia, Spain.
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25
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Nimrichter L, Rodrigues ML, Del Poeta M. Exploiting Lipids to Develop Anticryptococcal Vaccines. CURRENT TROPICAL MEDICINE REPORTS 2019. [DOI: 10.1007/s40475-019-00178-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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26
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Hartmann DO, Piontkivska D, Moreira CJS, Silva Pereira C. Ionic Liquids Chemical Stress Triggers Sphingoid Base Accumulation in Aspergillus nidulans. Front Microbiol 2019; 10:864. [PMID: 31105664 PMCID: PMC6491925 DOI: 10.3389/fmicb.2019.00864] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2019] [Accepted: 04/04/2019] [Indexed: 11/30/2022] Open
Abstract
Understanding stress responses and signaling pathways in fungi became a fundamental need for the discovery of new specific antifungal targets for fighting emerging life-threatening pathogens and drug resistance. Ionic liquids constitute a unique class of chemicals, which structural diversity and tunable physical and chemical properties can provide a great diversity of stimuli. In this study, we propose the use of ionic liquids as tools to unravel signaling of stress responses in the filamentous fungus Aspergillus nidulans. We assessed how three ionic liquids with distinct effects over the cell wall and plasma membrane affect the biosynthesis of sphingolipids and accumulation of free sphingoid bases in this fungus. The stress imposed by each ionic liquid triggered the sphingolipid biosynthetic pathway and led to distinct profiles of sphingoid bases accumulation. Dodecyltributylphosphonium chloride and 1-decyl-3-methylimidazolium chloride induced the accumulation of sphingosine and of a yet unknown sphingoid base, respectively, while cholinium decanoate did not seem to accumulate any of these intermediates. This study brings further light to the roles of sphingoid bases in A. nidulans. In particular, sphingosine as a possible response mediator to cell wall damage induced by dodecyltributylphosphonium chloride, and involvement of an unknown sphingoid base in the response to plasma membrane permeabilization caused by 1-decyl-3-methylimidazolium chloride. In addition, we completed the genetic assignment of the glucosylceramide pathway in A. nidulans through the identification of the sphingolipid Δ4-desaturase gene (AN4405). The knowledge established reinforces the idea of targeting sphingolipids biosynthesis in the search of improved antifungal compounds.
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Affiliation(s)
- Diego O Hartmann
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB NOVA), Oeiras, Portugal
| | - Daryna Piontkivska
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB NOVA), Oeiras, Portugal
| | - Carlos J S Moreira
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB NOVA), Oeiras, Portugal
| | - Cristina Silva Pereira
- Instituto de Tecnologia Química e Biológica António Xavier, Universidade Nova de Lisboa (ITQB NOVA), Oeiras, Portugal
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27
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Huber A, Oemer G, Malanovic N, Lohner K, Kovács L, Salvenmoser W, Zschocke J, Keller MA, Marx F. Membrane Sphingolipids Regulate the Fitness and Antifungal Protein Susceptibility of Neurospora crassa. Front Microbiol 2019; 10:605. [PMID: 31031714 PMCID: PMC6471014 DOI: 10.3389/fmicb.2019.00605] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2018] [Accepted: 03/11/2019] [Indexed: 02/06/2023] Open
Abstract
The membrane sphingolipid glucosylceramide (GlcCer) plays an important role in fungal fitness and adaptation to most diverse environments. Moreover, reported differences in the structure of GlcCer between fungi, plants and animals render this pathway a promising target for new generation therapeutics. Our knowledge about the GlcCer biosynthesis in fungi is mainly based on investigations of yeasts, whereas this pathway is less well characterized in molds. We therefore performed a detailed lipidomic profiling of GlcCer species present in Neurospora crassa and comprehensively show that the deletion of genes encoding enzymes involved in GlcCer biosynthesis affects growth, conidiation and stress response in this model fungus. Importantly, our study evidences that differences in the pathway intermediates and their functional role exist between N. crassa and other fungal species. We further investigated the role of GlcCer in the susceptibility of N. crassa toward two small cysteine-rich and cationic antimicrobial proteins (AMPs), PAF and PAFB, which originate from the filamentous ascomycete Penicillium chrysogenum. The interaction of these AMPs with the fungal plasma membrane is crucial for their antifungal toxicity. We found that GlcCer determines the susceptibility of N. crassa toward PAF, but not PAFB. A higher electrostatic affinity of PAFB than PAF to anionic membrane surfaces might explain the difference in their antifungal mode of action.
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Affiliation(s)
- Anna Huber
- Division of Molecular Biology, Biocenter, Medical University of Innsbruck, Innsbruck, Austria
| | - Gregor Oemer
- Division of Human Genetics, Medical University of Innsbruck, Innsbruck, Austria
| | - Nermina Malanovic
- Institute of Molecular Biosciences, Biophysics Division, University of Graz, Graz, Austria
| | - Karl Lohner
- Institute of Molecular Biosciences, Biophysics Division, University of Graz, Graz, Austria
| | - Laura Kovács
- Division of Molecular Biology, Biocenter, Medical University of Innsbruck, Innsbruck, Austria
| | | | - Johannes Zschocke
- Division of Human Genetics, Medical University of Innsbruck, Innsbruck, Austria
| | - Markus A Keller
- Division of Human Genetics, Medical University of Innsbruck, Innsbruck, Austria
| | - Florentine Marx
- Division of Molecular Biology, Biocenter, Medical University of Innsbruck, Innsbruck, Austria
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28
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Cryptococcus neoformans Glucuronoxylomannan and Sterylglucoside Are Required for Host Protection in an Animal Vaccination Model. mBio 2019; 10:mBio.02909-18. [PMID: 30940711 PMCID: PMC6445945 DOI: 10.1128/mbio.02909-18] [Citation(s) in RCA: 45] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
Abstract
The number of deaths from cryptococcal meningitis is around 180,000 per year. The disease is the second leading cause of mortality among individuals with AIDS. Antifungal treatment is costly and associated with adverse effects and resistance, evidencing the urgency of development of both therapeutic and prophylactic tools. Here we demonstrate the key roles of polysaccharide- and glycolipid-containing structures in a vaccination model to prevent cryptococcosis. Cryptococcus neoformans is an encapsulated fungal pathogen that causes meningoencephalitis. There are no prophylactic tools for cryptococcosis. Previously, our group showed that a C. neoformans mutant lacking the gene encoding sterylglucosidase (Δsgl1) induced protection in both immunocompetent and immunocompromised murine models of cryptococcosis. Since sterylglucosidase catalyzes degradation of sterylglucosides (SGs), accumulation of this glycolipid could be responsible for protective immunity. In this study, we analyzed whether the activity of SGs is sufficient for the protective effect induced by the Δsgl1 strain. We observed that the accumulation of SGs impacted several properties of the main polysaccharide that composes the fungal capsule, glucuronoxylomannan (GXM). We therefore used genetic manipulation to delete the SGL1 gene in the acapsular mutant Δcap59 to generate a double mutant (strain Δcap59/Δsgl1) that was shown to be nonpathogenic and cleared from the lung of mice within 7 days post-intranasal infection. The inflammatory immune response triggered by the Δcap59/Δsgl1 mutant in the lung differed from the response seen with the other strains. The double mutant did not induce protection in a vaccination model, suggesting that SG-related protection requires the main capsular polysaccharide. Finally, GXM-containing extracellular vesicles (EVs) enriched in SGs delayed the acute lethality of Galleria mellonella against C. neoformans infection. These studies highlighted a key role for GXM and SGs in inducing protection against a secondary cryptococcal infection, and, since EVs notoriously contain GXM, these results suggest the potential use of Δsgl1 EVs as a vaccination strategy for cryptococcosis.
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29
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Fabri JHTM, Godoy NL, Rocha MC, Munshi M, Cocio TA, von Zeska Kress MR, Fill TP, da Cunha AF, Del Poeta M, Malavazi I. The AGC Kinase YpkA Regulates Sphingolipids Biosynthesis and Physically Interacts With SakA MAP Kinase in Aspergillus fumigatus. Front Microbiol 2019; 9:3347. [PMID: 30692984 PMCID: PMC6339957 DOI: 10.3389/fmicb.2018.03347] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2018] [Accepted: 12/28/2018] [Indexed: 12/12/2022] Open
Abstract
Sphingolipids (SL) are complex lipids and components of the plasma membrane which are involved in numerous cellular processes, as well as important for virulence of different fungal pathogens. In yeast, SL biosynthesis is regulated by the "AGC kinases" Ypk1 and Ypk2, which also seem to connect the SL biosynthesis with the cell wall integrity (CWI) and the High Osmolarity Glycerol (HOG) pathways. Here, we investigate the role of ypkA Y PK1 in SL biosynthesis and its relationship with the CWI and the HOG pathways in the opportunistic human pathogen Aspergillus fumigatus. We found that ypkA is important for fungal viability, since the ΔypkA strain presented a drastically sick phenotype and complete absence of conidiation. We observed that under repressive condition, the conditional mutant niiA::ypkA exhibited vegetative growth defects, impaired germination and thermosensitivity. In addition, the ypkA loss of function caused a decrease in glycosphingolipid (GSL) levels, especially the metabolic intermediates belonging to the neutral GSL branch including dihydroceramide (DHC), ceramide (Cer), and glucosylceramide (GlcCer), but interestingly a small increase in ergosterol content. Genetic analyzes showed that ypkA genetically interacts with the MAP kinases of CWI and HOG pathways, mpkA and sakA, respectively, while only SakA physically interacts with YpkA. Our results suggest that YpkA is important for fungal survival through the regulation of GSL biosynthesis and cross talks with A. fumigatus MAP kinase pathways.
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Affiliation(s)
| | - Naiane Lima Godoy
- Departamento de Genética e Evolução, Centro de Ciências Biológicas e da Saúde, Universidade Federal de São Carlos, São Carlos, Brazil
| | - Marina Campos Rocha
- Departamento de Genética e Evolução, Centro de Ciências Biológicas e da Saúde, Universidade Federal de São Carlos, São Carlos, Brazil
| | - Mansa Munshi
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY, United States
| | - Tiago Alexandre Cocio
- Departamento de Genética e Evolução, Centro de Ciências Biológicas e da Saúde, Universidade Federal de São Carlos, São Carlos, Brazil
| | - Marcia Regina von Zeska Kress
- Departamento de Análises Clínicas Toxicológicas e Bromatológicas, Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | | | - Anderson Ferreira da Cunha
- Departamento de Genética e Evolução, Centro de Ciências Biológicas e da Saúde, Universidade Federal de São Carlos, São Carlos, Brazil
| | - Maurizio Del Poeta
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY, United States.,Division of Infectious Diseases, School of Medicine, Stony Brook University, Stony Brook, NY, United States.,Institute of Chemical Biology and Drug Discovery, Stony Brook University, Stony Brook, NY, United States.,Veterans Administration Medical Center, Northport, NY, United States
| | - Iran Malavazi
- Departamento de Genética e Evolução, Centro de Ciências Biológicas e da Saúde, Universidade Federal de São Carlos, São Carlos, Brazil
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30
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Abstract
Filamentous and dimorphic fungi cause invasive mycoses associated with high mortality rates. Among the fungal determinants involved in the establishment of infection, glycosphingolipids (GSLs) have gained increased interest in the last few decades. GSLs are ubiquitous membrane components that have been isolated from both filamentous and dimorphic species and play a crucial role in polarized growth as well as hypha-to-yeast transition. In fungi, two major classes of GSLs are found: neutral and acidic GSLs. Neutral GSLs comprise glucosylceramide and galactosylceramide, which utilize Δ4-Δ8-9-methyl-sphingadienine as a sphingoid base, linked to a C16-18 fatty acid chain, forming ceramide, and to a sugar residue, such as glucose or galactose. In contrast, acidic GSLs include glycosylinositol phosphorylceramides (GIPCs), composed of phytosphingosine attached to a long or very long fatty acid chain (C18-26) and to diverse and complex glycan groups via an inositol-phosphate linker. GIPCs are absent in mammalian cells, while fungal glucosylceramide and galactosylceramide are present but diverge structurally from their counterparts. Therefore, these compounds and their biosynthetic pathways represent potential targets for the development of selective therapeutic strategies. In this minireview, we discuss the enzymatic steps involved in the production of fungal GSLs, analyze their structure, and address the role of the currently characterized genes in the biology and pathogenesis of filamentous and dimorphic fungi.
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31
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Ferdouse J, Yamamoto Y, Taguchi S, Yoshizaki Y, Takamine K, Kitagaki H. Glycosylceramide modifies the flavor and metabolic characteristics of sake yeast. PeerJ 2018; 6:e4768. [PMID: 29761062 PMCID: PMC5949206 DOI: 10.7717/peerj.4768] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2018] [Accepted: 04/24/2018] [Indexed: 12/17/2022] Open
Abstract
In the manufacture of sake, Japanese traditional rice wine, sake yeast is fermented with koji, which is steamed rice fermented with the non-pathogenic fungus Aspergillus oryzae. During fermentation, sake yeast requires lipids, such as unsaturated fatty acids and sterols, in addition to substances provided by koji enzymes for fermentation. However, the role of sphingolipids on the brewing characteristics of sake yeast has not been studied. In this study, we revealed that glycosylceramide, one of the sphingolipids abundant in koji, affects yeast fermentation. The addition of soy, A. oryzae, and Grifola frondosa glycosylceramide conferred a similar effect on the flavor profiles of sake yeast. In particular, the addition of A. oryzae and G. frondosa glycosylceramide were very similar in terms of the decreases in ethyl caprylate and ethyl 9-decenoate. The addition of soy glycosylceramide induced metabolic changes to sake yeast such as a decrease in glucose, increases in ethanol and glycerol and changes in several amino acids and organic acids concentrations. Tricarboxylic acid (TCA) cycle, pyruvate metabolism, starch and sucrose metabolism, and glycerolipid metabolism were overrepresented in the cultures incubated with sake yeast and soy glycosylceramide. This is the first study of the effect of glycosylceramide on the flavor and metabolic profile of sake yeast.
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Affiliation(s)
- Jannatul Ferdouse
- Department of Biochemistry and Applied Biosciences, United Graduate School of Agricultural Sciences, Kagoshima University, Kagoshima, Japan
| | - Yuki Yamamoto
- Department of Environmental Science, Faculty of Agriculture, Saga University, Saga, Japan
| | - Seiga Taguchi
- Department of Environmental Science, Faculty of Agriculture, Saga University, Saga, Japan
| | - Yumiko Yoshizaki
- Department of Biochemistry and Applied Biosciences, United Graduate School of Agricultural Sciences, Kagoshima University, Kagoshima, Japan
| | - Kazunori Takamine
- Department of Biochemistry and Applied Biosciences, United Graduate School of Agricultural Sciences, Kagoshima University, Kagoshima, Japan
| | - Hiroshi Kitagaki
- Department of Biochemistry and Applied Biosciences, United Graduate School of Agricultural Sciences, Kagoshima University, Kagoshima, Japan.,Department of Environmental Science, Faculty of Agriculture, Saga University, Saga, Japan
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32
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Agustinho DP, Miller LC, Li LX, Doering TL. Peeling the onion: the outer layers of Cryptococcus neoformans. Mem Inst Oswaldo Cruz 2018; 113:e180040. [PMID: 29742198 PMCID: PMC5951675 DOI: 10.1590/0074-02760180040] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 02/27/2018] [Indexed: 12/20/2022] Open
Abstract
Cryptococcus neoformans is an opportunistic fungal pathogen
that is ubiquitous in the environment. It causes a deadly meningitis that is
responsible for over 180,000 deaths worldwide each year, including 15% of all
AIDS-related deaths. The high mortality rates for this infection, even with
treatment, suggest a need for improved therapy. Unique characteristics of
C. neoformans may suggest directions for drug discovery.
These include features of three structures that surround the cell: the plasma
membrane, the cell wall around it, and the outermost polysaccharide capsule. We
review current knowledge of the fundamental biology of these fascinating
structures and highlight open questions in the field, with the goal of
stimulating further investigation that will advance basic knowledge and human
health.
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Affiliation(s)
- Daniel P Agustinho
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Liza C Miller
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Lucy X Li
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, USA
| | - Tamara L Doering
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, USA
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33
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Acylhydrazones as Antifungal Agents Targeting the Synthesis of Fungal Sphingolipids. Antimicrob Agents Chemother 2018; 62:AAC.00156-18. [PMID: 29507066 PMCID: PMC5923120 DOI: 10.1128/aac.00156-18] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 02/21/2018] [Indexed: 01/19/2023] Open
Abstract
The incidence of invasive fungal infections has risen dramatically in recent decades. Current antifungal drugs are either toxic, likely to interact with other drugs, have a narrow spectrum of activity, or induce fungal resistance. Hence, there is a great need for new antifungals, possibly with novel mechanisms of action. Previously our group reported an acylhydrazone called BHBM that targeted the sphingolipid pathway and showed strong antifungal activity against several fungi. In this study, we screened 19 derivatives of BHBM. Three out of 19 derivatives were highly active against Cryptococcus neoformansin vitro and had low toxicity in mammalian cells. In particular, one of them, called D13, had a high selectivity index and showed better activity in an animal model of cryptococcosis, candidiasis, and pulmonary aspergillosis. D13 also displayed suitable pharmacokinetic properties and was able to pass through the blood-brain barrier. These results suggest that acylhydrazones are promising molecules for the research and development of new antifungal agents.
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34
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Mechanisms of Pulmonary Escape and Dissemination by Cryptococcus neoformans. J Fungi (Basel) 2018; 4:jof4010025. [PMID: 29463005 PMCID: PMC5872328 DOI: 10.3390/jof4010025] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2018] [Revised: 02/09/2018] [Accepted: 02/16/2018] [Indexed: 12/15/2022] Open
Abstract
Cryptococcus neoformans is a common environmental saprophyte and human fungal pathogen that primarily causes disease in immunocompromised individuals. Similar to many environmentally acquired human fungal pathogens, C. neoformans initiates infection in the lungs. However, the main driver of mortality is invasive cryptococcosis leading to fungal meningitis. After C. neoformans gains a foothold in the lungs, a critical early step in invasion is transversal of the respiratory epithelium. In this review, we summarize current knowledge relating to pulmonary escape. We focus on fungal factors that allow C. neoformans to disseminate from the lungs via intracellular and extracellular routes.
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35
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Raj S, Nazemidashtarjandi S, Kim J, Joffe L, Zhang X, Singh A, Mor V, Desmarini D, Djordjevic J, Raleigh DP, Rodrigues ML, London E, Del Poeta M, Farnoud AM. Changes in glucosylceramide structure affect virulence and membrane biophysical properties of Cryptococcus neoformans. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1859:2224-2233. [PMID: 28865794 DOI: 10.1016/j.bbamem.2017.08.017] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/13/2017] [Revised: 08/03/2017] [Accepted: 08/27/2017] [Indexed: 11/19/2022]
Abstract
Fungal glucosylceramide (GlcCer) is a plasma membrane sphingolipid in which the sphingosine backbone is unsaturated in carbon position 8 (C8) and methylated in carbon position 9 (C9). Studies in the fungal pathogen, Cryptococcus neoformans, have shown that loss of GlcCer synthase activity results in complete loss of virulence in the mouse model. However, whether the loss of virulence is due to the lack of the enzyme or to the loss of the sphingolipid is not known. In this study, we used genetic engineering to alter the chemical structure of fungal GlcCer and studied its effect on fungal growth and pathogenicity. Here we show that unsaturation in C8 and methylation in C9 is required for virulence in the mouse model without affecting fungal growth in vitro or common virulence factors. However, changes in GlcCer structure led to a dramatic susceptibility to membrane stressors resulting in increased cell membrane permeability and rendering the fungal mutant unable to grow within host macrophages. Biophysical studies using synthetic vesicles containing GlcCer revealed that the saturated and unmethylated sphingolipid formed vesicles with higher lipid order that were more likely to phase separate into ordered domains. Taken together, these studies show for the first time that a specific structure of GlcCer is a major regulator of membrane permeability required for fungal pathogenicity.
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Affiliation(s)
- Shriya Raj
- Department of Mycology, Institut Pasteur, Paris, France
| | | | - Jihyun Kim
- Department of Chemistry and Biochemistry, Stony Brook University, Stony Brook, NY, USA
| | - Luna Joffe
- Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro (UFRJ), Brazil
| | - Xiaoxue Zhang
- Department of Chemistry and Biochemistry, Stony Brook University, Stony Brook, NY, USA
| | - Ashutosh Singh
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY, USA
| | - Visesato Mor
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY, USA
| | - Desmarini Desmarini
- Fungal Pathogenesis Laboratory, Centre for Infectious Diseases and Microbiology, The Westmead Institute for Medical Research, Westmead, NSW, Australia
| | - Julianne Djordjevic
- Fungal Pathogenesis Laboratory, Centre for Infectious Diseases and Microbiology, The Westmead Institute for Medical Research, Westmead, NSW, Australia; Westmead Clinical School, University of Sydney at Westmead Hospital, Westmead, NSW, Australia; Marie Bashir Institute for Infectious Diseases and Biosecurity, University of Sydney, NSW, Australia
| | - Daniel P Raleigh
- Department of Chemistry and Biochemistry, Stony Brook University, Stony Brook, NY, USA
| | - Marcio L Rodrigues
- Departamento de Microbiologia Geral, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio de Janeiro (UFRJ), Brazil; Centro de Desenvolvimento Tecnológico em Saúde (CDTS) da Fundação Oswaldo Cruz (Fiocruz), Rio de Janeiro, Brazil
| | - Erwin London
- Department of Chemistry and Biochemistry, Stony Brook University, Stony Brook, NY, USA
| | - Maurizio Del Poeta
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY, USA; Veterans Administration Medical Center, Northport, NY, USA; Division of Infectious Diseases, Stony Brook University, Stony Brook, NY, USA.
| | - Amir M Farnoud
- Department of Chemical and Biomolecular Engineering, Ohio University, Athens, OH, USA.
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Singh A, MacKenzie A, Girnun G, Del Poeta M. Analysis of sphingolipids, sterols, and phospholipids in human pathogenic Cryptococcus strains. J Lipid Res 2017; 58:2017-2036. [PMID: 28811322 DOI: 10.1194/jlr.m078600] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Revised: 08/13/2017] [Indexed: 01/07/2023] Open
Abstract
Cryptococcus species cause invasive infections in humans. Lipids play an important role in the progression of these infections. Independent studies done by our group and others provide some detail about the functions of these lipids in Cryptococcus infections. However, the pathways of biosynthesis and the metabolism of these lipids are not completely understood. To thoroughly understand the physiological role of these Cryptococcus lipids, a proper structure and composition analysis of Cryptococcus lipids is demanded. In this study, a detailed spectroscopic analysis of lipid extracts from Cryptococcus gattii and Cryptococcus grubii strains is presented. Sphingolipid profiling by LC-ESI-MS/MS was used to analyze sphingosine, dihydrosphingosine, sphingosine-1-phosphate, dihydrosphingosine-1-phosphate, ceramide, dihydroceramide, glucosylceramide, phytosphingosine, phytosphingosine-1-phosphate, phytoceramide, α-hydroxy phytoceramide, and inositolphosphorylceramide species. A total of 13 sterol species were identified using GC-MS, where ergosterol is the most abundant species. The 31P-NMR-based phospholipid analysis identified phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol, phosphatidylserine, phosphatidyl-N,N-dimethylethanolamine, phosphatidyl-N-monomethylethanolamine, phosphatidylglycerol, phosphatidic acid, and lysophosphatidylethanolamine. A comparison of lipid profiles among different Cryptococcus strains illustrates a marked change in the metabolic flux of these organisms, especially sphingolipid metabolism. These data improve our understanding of the structure, biosynthesis, and metabolism of common lipid groups of Cryptococcus and should be useful while studying their functional significance and designing therapeutic interventions.
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Affiliation(s)
- Ashutosh Singh
- Department of Molecular Genetics and Microbiology and Stony Brook University, Stony Brook, NY 11794
| | | | - Geoffrey Girnun
- Department of Pathology, Stony Brook School of Medicine, Stony Brook, NY 11794
| | - Maurizio Del Poeta
- Department of Molecular Genetics and Microbiology and Stony Brook University, Stony Brook, NY 11794 .,Veterans Administration Medical Center, Northport, NY 11768.,Division of Infectious Diseases, Stony Brook University, Stony Brook, NY 11794
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Sphingolipids from the human fungal pathogen Aspergillus fumigatus. Biochimie 2017; 141:9-15. [PMID: 28652019 DOI: 10.1016/j.biochi.2017.06.012] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 06/21/2017] [Indexed: 01/24/2023]
Abstract
Sphingolipids (SPLs) are key components of the plasma membrane in yeast and filamentous fungi. These molecules are involved in a number of cellular processes, and particularly, SGLs are essential components of the highly polarized fungal growth where they are required for the formation of the polarisome organization at the hyphal apex. Aspergillus fumigatus, a human fungal pathogen, produce SGLs that are discriminated into neutral cerebrosides, glycosylinositolphosphoceramides (GIPCs) and glycosylphosphatidylinositol (GPI) anchors. In addition to complex hydrophilic head groups of GIPCs, A. fumigatus is, to date, the sole fungus that produces a GPI-anchored polysaccharide. These SPLs follow three different biosynthetic pathways. Genetics blockage leading to the inhibition of any SPL biosynthesis or to the alteration of the structure of SPL induces growth and virulence defects. The complete lipid moiety of SPLs is essential for the lipid microdomain organization and their biosynthetic pathways are potential antifungal targets but remains understudied.
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Alves de Castro P, dos Reis TF, Dolan SK, Manfiolli AO, Brown NA, Jones GW, Doyle S, Riaño-Pachón DM, Squina FM, Caldana C, Singh A, Del Poeta M, Hagiwara D, Silva-Rocha R, Goldman GH. The Aspergillus fumigatus SchA SCH9 kinase modulates SakA HOG1 MAP kinase activity and it is essential for virulence. Mol Microbiol 2016; 102:642-671. [PMID: 27538790 PMCID: PMC5207228 DOI: 10.1111/mmi.13484] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/17/2016] [Indexed: 02/06/2023]
Abstract
The serine-threonine kinase TOR, the Target of Rapamycin, is an important regulator of nutrient, energy and stress signaling in eukaryotes. Sch9, a Ser/Thr kinase of AGC family (the cAMP-dependent PKA, cGMP- dependent protein kinase G and phospholipid-dependent protein kinase C family), is a substrate of TOR. Here, we characterized the fungal opportunistic pathogen Aspergillus fumigatus Sch9 homologue (SchA). The schA null mutant was sensitive to rapamycin, high concentrations of calcium, hyperosmotic stress and SchA was involved in iron metabolism. The ΔschA null mutant showed increased phosphorylation of SakA, the A. fumigatus Hog1 homologue. The schA null mutant has increased and decreased trehalose and glycerol accumulation, respectively, suggesting SchA performs different roles for glycerol and trehalose accumulation during osmotic stress. The schA was transcriptionally regulated by osmotic stress and this response was dependent on SakA and MpkC. The double ΔschA ΔsakA and ΔschA ΔmpkC mutants were more sensitive to osmotic stress than the corresponding parental strains. Transcriptomics and proteomics identified direct and indirect targets of SchA post-exposure to hyperosmotic stress. Finally, ΔschA was avirulent in a low dose murine infection model. Our results suggest there is a complex network of interactions amongst the A. fumigatus TOR, SakA and SchA pathways.
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Affiliation(s)
- Patrícia Alves de Castro
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Thaila Fernanda dos Reis
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Stephen K. Dolan
- Department of Biology, Maynooth University, Maynooth, Co. Kildare, Ireland
| | - Adriana Oliveira Manfiolli
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Neil Andrew Brown
- Plant Biology and Crop Science, Rothamsted Research, Harpenden, Herts AL5 2JQ, UK
| | - Gary W. Jones
- Department of Biology, Maynooth University, Maynooth, Co. Kildare, Ireland
| | - Sean Doyle
- Department of Biology, Maynooth University, Maynooth, Co. Kildare, Ireland
| | - Diego M. Riaño-Pachón
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Caixa Postal 6192, Campinas, São Paulo, CEP 13083-970, Brasil
| | - Fábio Márcio Squina
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Caixa Postal 6192, Campinas, São Paulo, CEP 13083-970, Brasil
| | - Camila Caldana
- Laboratório Nacional de Ciência e Tecnologia do Bioetanol (CTBE), Centro Nacional de Pesquisa em Energia e Materiais (CNPEM), Caixa Postal 6192, Campinas, São Paulo, CEP 13083-970, Brasil
- Max Planck Partner Group at Brazilian Bioethanol Science and Technology Laboratory, Brazilian Center for Research in Energy and Materials, São Paulo, Brazil
| | - Ashutosh Singh
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY, USA
| | - Maurizio Del Poeta
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY, USA
| | - Daisuke Hagiwara
- Medical Mycology Research Center, Chiba University, Chiba, Japan
| | - Rafael Silva-Rocha
- Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - Gustavo H. Goldman
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
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Malachowski AN, Yosri M, Park G, Bahn YS, He Y, Olszewski MA. Systemic Approach to Virulence Gene Network Analysis for Gaining New Insight into Cryptococcal Virulence. Front Microbiol 2016; 7:1652. [PMID: 27833589 PMCID: PMC5081415 DOI: 10.3389/fmicb.2016.01652] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2016] [Accepted: 10/04/2016] [Indexed: 11/13/2022] Open
Abstract
Cryptococcus neoformans is pathogenic yeast, responsible for highly lethal infections in compromised patients around the globe. C. neoformans typically initiates infections in mammalian lung tissue and subsequently disseminates to the central nervous system where it causes significant pathologies. Virulence genes of C. neoformans are being characterized at an increasing rate, however, we are far from a comprehensive understanding of their roles and genetic interactions. Some of these reported virulence genes are scattered throughout different databases, while others are not yet included. This study gathered and analyzed 150 reported virulence associated factors (VAFs) of C. neoformans. Using the web resource STRING database, our study identified different interactions between the total VAFs and those involved specifically in lung and brain infections and identified a new strain specific virulence gene, SHO1, involved in the mitogen-activated protein kinase signaling pathway. As predicted by our analysis, SHO1 expression enhanced C. neoformans virulence in a mouse model of pulmonary infection, contributing to enhanced non-protective immune Th2 bias and progressively enhancing fungal growth in the infected lungs. Sequence analysis indicated 77.4% (116) of total studied VAFs are soluble proteins, and 22.7% (34) are transmembrane proteins. Motifs involved in regulation and signaling such as protein kinases and transcription factors are highly enriched in Cryptococcus VAFs. Altogether, this study represents a pioneering effort in analysis of the virulence composite network of C. neoformans using a systems biology approach.
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Affiliation(s)
- Antoni N Malachowski
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Medical School, Ann ArborMI, USA; VA Ann Arbor Healthcare System Research Service (11R), Ann ArborMI, USA
| | - Mohamed Yosri
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Medical School, Ann ArborMI, USA; VA Ann Arbor Healthcare System Research Service (11R), Ann ArborMI, USA; The Regional Center for Mycology and Biotechnology, Al-Azhar UniversityCairo, Egypt
| | - Goun Park
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University Seoul, South Korea
| | - Yong-Sun Bahn
- Department of Biotechnology, College of Life Science and Biotechnology, Yonsei University Seoul, South Korea
| | - Yongqun He
- Unit for Laboratory Animal Medicine, University of Michigan Medical School, Ann ArborMI, USA; Department of Microbiology and Immunology, University of Michigan Medical School, Ann ArborMI, USA; Center for Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann ArborMI, USA
| | - Michal A Olszewski
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, University of Michigan Medical School, Ann ArborMI, USA; VA Ann Arbor Healthcare System Research Service (11R), Ann ArborMI, USA
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40
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Fernandes CM, de Castro PA, Singh A, Fonseca FL, Pereira MD, Vila TVM, Atella GC, Rozental S, Savoldi M, Del Poeta M, Goldman GH, Kurtenbach E. Functional characterization of the Aspergillus nidulans glucosylceramide pathway reveals that LCB Δ8-desaturation and C9-methylation are relevant to filamentous growth, lipid raft localization and Psd1 defensin activity. Mol Microbiol 2016; 102:488-505. [PMID: 27479571 DOI: 10.1111/mmi.13474] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/29/2016] [Indexed: 12/22/2022]
Abstract
C8-desaturated and C9-methylated glucosylceramide (GlcCer) is a fungal-specific sphingolipid that plays an important role in the growth and virulence of many species. In this work, we investigated the contribution of Aspergillus nidulans sphingolipid Δ8-desaturase (SdeA), sphingolipid C9-methyltransferases (SmtA/SmtB) and glucosylceramide synthase (GcsA) to fungal phenotypes, sensitivity to Psd1 defensin and Galleria mellonella virulence. We showed that ΔsdeA accumulated C8-saturated and unmethylated GlcCer, while gcsA deletion impaired GlcCer synthesis. Although increased levels of unmethylated GlcCer were observed in smtA and smtB mutants, ΔsmtA and wild-type cells showed a similar 9,Me-GlcCer content, reduced by 50% in the smtB disruptant. The compromised 9,Me-GlcCer production in the ΔsmtB strain was not accompanied by reduced filamentation or defects in cell polarity. When combined with the smtA deletion, smtB repression significantly increased unmethylated GlcCer levels and compromised filamentous growth. Furthermore, sdeA and gcsA mutants displayed growth defects and raft mislocalization, which were accompanied by reduced neutral lipids levels and attenuated G. mellonella virulence in the ΔgcsA strain. Finally, ΔsdeA and ΔgcsA showed increased resistance to Psd1, suggesting that GlcCer synthesis and fungal sphingoid base structure specificities are relevant not only to differentiation but also to proper recognition by this antifungal defensin.
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Affiliation(s)
- C M Fernandes
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - P A de Castro
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - A Singh
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY, USA
| | - F L Fonseca
- Centro de Desenvolvimento Tecnológico em Saúde, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - M D Pereira
- Departamento de Bioquímica, Instituto de Química, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - T V M Vila
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - G C Atella
- Instituto de Bioquímica Médica Leopoldo de Meis, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - S Rozental
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - M Savoldi
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - M Del Poeta
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY, USA
| | - G H Goldman
- Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
| | - E Kurtenbach
- Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil.
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de Medeiros LN, Domitrovic T, de Andrade PC, Faria J, Bergter EB, Weissmüller G, Kurtenbach E. Psd1 binding affinity toward fungal membrane components as assessed by SPR: The role of glucosylceramide in fungal recognition and entry. Biopolymers 2016; 102:456-64. [PMID: 25283273 DOI: 10.1002/bip.22570] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Revised: 09/17/2014] [Accepted: 09/27/2014] [Indexed: 12/11/2022]
Abstract
Psd1 is a plant defensin that has antifungal activity against several pathogenic and nonpathogenic fungi. Previous analysis of Psd1 chemical shift perturbations by nuclear magnetic resonance (NMR) spectroscopy demonstrated that this defensin interacts with phospholipids and the sphingolipid glucosylceramide isolated from Fusarium solani (GlcCer(Fusarium solani)). In this study, these interactions were evaluated by real-time surface plasmon resonance (SPR) analysis. The data obtained demonstrated that Psd1 could bind more strongly to small unilamellar vesicles (SUV)-containing GlcCer(Fusarium solani) than to SUV that was composed of phosphatidylcholine (PC) alone or was enriched with GlcCer that had been isolated from soybeans. An increase in the SPR response after cholesterol or ergosterol incorporation in PC-SUV was detected; however, SUV composed of PC:Erg (7:3; molar:molar) became unstable in the presence of Psd1, suggesting membrane destabilization. We also observed a lack of Psd1 internalization in Candida albicans strains that were deficient in the glucosyl ceramide synthase gene. Together, these data indicate that GlcCer is essential for Psd1 anchoring in the fungal plasma membrane as well as internalization.
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Affiliation(s)
- Luciano Neves de Medeiros
- Programa de Biologia Molecular e Estrutural, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, 21941-902, Brasil; Instituto Nacional para Pesquisa Translacional em Saúde e Ambiente na Região Amazônica, Conselho Nacional de Desenvolvimento Científico e Tecnológico/MCT, Rio de Janeiro, RJ, 21941-902, Brasil
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Glucosylceramide Administration as a Vaccination Strategy in Mouse Models of Cryptococcosis. PLoS One 2016; 11:e0153853. [PMID: 27082428 PMCID: PMC4833283 DOI: 10.1371/journal.pone.0153853] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2015] [Accepted: 04/05/2016] [Indexed: 01/05/2023] Open
Abstract
Cryptococcus neoformans is an opportunistic fungal pathogen and the causative agent of the disease cryptococcosis. Cryptococcosis is initiated as a pulmonary infection and in conditions of immune deficiency disseminates to the blood stream and central nervous system, resulting in life-threatening meningoencephalitis. A number of studies have focused on the development of a vaccine against Cryptococcus, primarily utilizing protein-conjugated components of the Cryptococcus polysaccharide capsule as antigen. However, there is currently no vaccine against Cryptococcus in the clinic. Previous studies have shown that the glycosphingolipid, glucosylceramide (GlcCer), is a virulence factor in C. neoformans and antibodies against this lipid inhibit fungal growth and cell division. In the present study, we have investigated the possibility of using GlcCer as a therapeutic agent against C. neoformans infections in mouse models of cryptococcosis. GlcCer purified from a non-pathogenic fungus, Candida utilis, was administered intraperitoneally, prior to infecting mice with a lethal dose of C. neoformans. GlcCer administration prevented the dissemination of C. neoformans from the lungs to the brain and led to 60% mouse survival. GlcCer administration did not cause hepatic injury and elicited an anti-GlcCer antibody response, which was observed independent of the route of administration and the strains of mouse. Taken together, our results suggest that fungal GlcCer can protect mice against lethal doses of C. neoformans infection and can provide a viable vaccination strategy against Cryptococcus.
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Singh A, Del Poeta M. Sphingolipidomics: An Important Mechanistic Tool for Studying Fungal Pathogens. Front Microbiol 2016; 7:501. [PMID: 27148190 PMCID: PMC4830811 DOI: 10.3389/fmicb.2016.00501] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2015] [Accepted: 03/28/2016] [Indexed: 01/28/2023] Open
Abstract
Sphingolipids form of a unique and complex group of bioactive lipids in fungi. Structurally, sphingolipids of fungi are quite diverse with unique differences in the sphingoid backbone, amide linked fatty acyl chain and the polar head group. Two of the most studied and conserved sphingolipid classes in fungi are the glucosyl- or galactosyl-ceramides and the phosphorylinositol containing phytoceramides. Comprehensive structural characterization and quantification of these lipids is largely based on advanced analytical mass spectrometry based lipidomic methods. While separation of complex lipid mixtures is achieved through high performance liquid chromatography, the soft - electrospray ionization tandem mass spectrometry allows a high sensitivity and selectivity of detection. Herein, we present an overview of lipid extraction, chromatographic separation and mass spectrometry employed in qualitative and quantitative sphingolipidomics in fungi.
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Affiliation(s)
- Ashutosh Singh
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony BrookNY, USA; Veterans Administration Medical Center, NorthportNY, USA
| | - Maurizio Del Poeta
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony BrookNY, USA; Veterans Administration Medical Center, NorthportNY, USA
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Rella A, Farnoud AM, Del Poeta M. Plasma membrane lipids and their role in fungal virulence. Prog Lipid Res 2015; 61:63-72. [PMID: 26703191 DOI: 10.1016/j.plipres.2015.11.003] [Citation(s) in RCA: 71] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Revised: 10/26/2015] [Accepted: 11/04/2015] [Indexed: 12/24/2022]
Abstract
There has been considerable evidence in recent years suggesting that plasma membrane lipids are important regulators of fungal pathogenicity. Various glycolipids have been shown to impart virulent properties in several fungal species, while others have been shown to play a role in host defense. In addition to their role as virulence factors, lipids also contribute to other virulence mechanisms such as drug resistance, biofilm formation, and release of extracellular vesicles. In addition, lipids also affect the mechanical properties of the plasma membrane through the formation of packed microdomains composed mainly of sphingolipids and sterols. Changes in the composition of lipid microdomains have been shown to disrupt the localization of virulence factors and affect fungal pathogenicity. This review gathers evidence on the various roles of plasma membrane lipids in fungal virulence and how lipids might contribute to the different processes that occur during infection and treatment. Insight into the role of lipids in fungal virulence can lead to an improved understanding of the process of fungal pathogenesis and the development of new lipid-mediated therapeutic strategies.
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Affiliation(s)
- Antonella Rella
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY 11794-5215, USA
| | - Amir M Farnoud
- Department of Chemical and Biomolecular Engineering, Ohio University, Athens, Ohio 45701, USA
| | - Maurizio Del Poeta
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY 11794-5215, USA
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Singh A, Rella A, Schwacke J, Vacchi-Suzzi C, Luberto C, Del Poeta M. Transmembrane transporter expression regulated by the glucosylceramide pathway in Cryptococcus neoformans. BMC Res Notes 2015; 8:681. [PMID: 26572681 PMCID: PMC4647647 DOI: 10.1186/s13104-015-1613-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2014] [Accepted: 10/20/2015] [Indexed: 12/26/2022] Open
Abstract
BACKGROUND The sphingolipid glucosylceramide (GlcCer) and factors involved in the fungal GlcCer pathways were shown earlier to be an integral part of fungal virulence, especially in fungal replication at 37 °C, in neutral/alkaline pH and 5 % CO2 environments (e.g. alveolar spaces). Two mutants, ∆gcs 1 lacking glucosylceramide synthase 1 gene (GCS1) which catalyzes the formation of sphingolipid GlcCer from the C9-methyl ceramide and ∆smt1 lacking sphingolipid C9 methyltransferase gene (SMT1), which adds a methyl group to position nine of the sphingosine backbone of ceramide, of this pathway were attenuated in virulence and have a growth defect at the above-mentioned conditions. These mutants with either no or structurally modified GlcCer located on the cell-membrane have reduced membrane rigidity, which may have altered not only the physical location of membrane proteins but also their expression, as the pathogen's mode of adaptation to changing need. Importantly, pathogens are known to adapt themselves to the changing host environments by altering their patterns of gene expression. RESULTS By transcriptional analysis of gene expression, we identified six genes whose expression was changed from their wild-type counterpart grown in the same conditions, i.e. they became either down regulated or up regulated in these two mutants. The microarray data was validated by real-time PCR, which confirmed their fold change in gene expression. All the six genes we identified, viz siderochrome-iron transporter (CNAG_02083), monosaccharide transporter (CNAG_05340), glucose transporter (CNAG_03772), membrane protein (CNAG_03912), membrane transport protein (CNAG_00539), and sugar transporter (CNAG_06963), are membrane-localized and have significantly altered gene expression levels. Therefore, we hypothesize that these genes function either independently or in tandem with a structurally modified cell wall/plasma membrane resulting from the modifications of the GlcCer pathway and thus possibly disrupt transmembrane signaling complex, which in turn contributes to cryptococcal osmotic, pH, ion homeostasis and its pathobiology. CONCLUSION Six genes identified from gene expression microarrays by gene set enrichment analysis and validated by RT-PCR, are membrane located and associated with the growth defect at neutral-alkaline pH due to the absence and or presence of a structurally modified GlcCer. They may be involved in the transmembrane signaling network in Cryptococcus neoformans, and therefore the pathobiology of the fungus in these conditions.
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Affiliation(s)
- Arpita Singh
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC, 29425, USA. .,Department of Medicine, Division of Infectious Diseases and International Health, University of Virginia, 345 Crispell Dr, Carter Harrison Building, Charlottesville, VA, 22908, USA.
| | - Antonella Rella
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC, 29425, USA. .,Department of Molecular Genetics and Microbiology, Stony Brook University, 150 Life Science Building, Stony Brook, NY, 11794, USA.
| | - John Schwacke
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC, 29425, USA. .,Integrated Systems and Solutions Division, Scientific Research Corporation, Remount Road, North Charleston, SC, 29406, USA.
| | - Caterina Vacchi-Suzzi
- Department of Preventive Medicine, University of Stony Brook, Stony Brook, NY, 11794, USA.
| | - Chiara Luberto
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC, 29425, USA. .,Department of Physiology and Biophysics, Stony Brook University, Stony Brook, NY, 11794, USA.
| | - Maurizio Del Poeta
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC, 29425, USA. .,Department of Molecular Genetics and Microbiology, Stony Brook University, 150 Life Science Building, Stony Brook, NY, 11794, USA. .,Department of Microbiology and Immunology, Medical University of South Carolina, Charleston, SC, 29425, USA. .,Department of Craniofacial Biology, Medical University of South Carolina, Charleston, SC, 29425, USA. .,Division of Infectious Diseases, Medical University of South Carolina, Charleston, SC, 29425, USA.
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46
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Rella A, Mor V, Farnoud AM, Singh A, Shamseddine AA, Ivanova E, Carpino N, Montagna MT, Luberto C, Del Poeta M. Role of Sterylglucosidase 1 (Sgl1) on the pathogenicity of Cryptococcus neoformans: potential applications for vaccine development. Front Microbiol 2015; 6:836. [PMID: 26322039 PMCID: PMC4531891 DOI: 10.3389/fmicb.2015.00836] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2015] [Accepted: 07/29/2015] [Indexed: 01/01/2023] Open
Abstract
Cryptococcosis caused by Cryptococcus neoformans and Cryptococcus gattii affects a large population and is a cause of significant morbidity and mortality. Despite its public health burden, there are currently no vaccines against cryptococcosis and new strategies against such infections are needed. In this study, we demonstrate that C. neoformans has the biochemical ability to metabolize sterylglucosides (SGs), a class of immunomodulatory glycolipids. Genetic manipulations that eliminate cryptococccal sterylglucosidase lead to the accumulation of SGs and generate a mutant strain (Δsgl1) that is non-pathogenic in the mouse models of cryptococcosis. Interestingly, this mutant strain acts as a vaccine strain and protects mice against cryptococcosis following infection with C. neoformans or C. gattii. The immunity induced by the Δsgl1 strain is not CD4+ T-cells dependent. Immunocompromised mice, which lack CD4+ T-cells, are able to control the infection by Δsgl1 and acquire immunity against the challenge by wild-type C. neoformans following vaccination with the Δsgl1 strain. These findings are particularly important in the context of HIV/AIDS immune deficiency and suggest that the Δsgl1 strain might provide a potential vaccination strategy against cryptococcosis.
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Affiliation(s)
- Antonella Rella
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook NY, USA
| | - Visesato Mor
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook NY, USA
| | - Amir M Farnoud
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook NY, USA
| | - Ashutosh Singh
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook NY, USA
| | | | - Elitza Ivanova
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook NY, USA
| | - Nicholas Carpino
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook NY, USA
| | - Maria T Montagna
- Department of Biomedical Science and Human Oncology, Hygiene Section, University of Bari Bari, Italy
| | - Chiara Luberto
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook NY, USA
| | - Maurizio Del Poeta
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook NY, USA
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Mor V, Rella A, Farnoud AM, Singh A, Munshi M, Bryan A, Naseem S, Konopka JB, Ojima I, Bullesbach E, Ashbaugh A, Linke MJ, Cushion M, Collins M, Ananthula HK, Sallans L, Desai PB, Wiederhold NP, Fothergill AW, Kirkpatrick WR, Patterson T, Wong LH, Sinha S, Giaever G, Nislow C, Flaherty P, Pan X, Cesar GV, de Melo Tavares P, Frases S, Miranda K, Rodrigues ML, Luberto C, Nimrichter L, Del Poeta M. Identification of a New Class of Antifungals Targeting the Synthesis of Fungal Sphingolipids. mBio 2015; 6:e00647. [PMID: 26106079 PMCID: PMC4479701 DOI: 10.1128/mbio.00647-15] [Citation(s) in RCA: 106] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
UNLABELLED Recent estimates suggest that >300 million people are afflicted by serious fungal infections worldwide. Current antifungal drugs are static and toxic and/or have a narrow spectrum of activity. Thus, there is an urgent need for the development of new antifungal drugs. The fungal sphingolipid glucosylceramide (GlcCer) is critical in promoting virulence of a variety of human-pathogenic fungi. In this study, we screened a synthetic drug library for compounds that target the synthesis of fungal, but not mammalian, GlcCer and found two compounds [N'-(3-bromo-4-hydroxybenzylidene)-2-methylbenzohydrazide (BHBM) and its derivative, 3-bromo-N'-(3-bromo-4-hydroxybenzylidene) benzohydrazide (D0)] that were highly effective in vitro and in vivo against several pathogenic fungi. BHBM and D0 were well tolerated in animals and are highly synergistic or additive to current antifungals. BHBM and D0 significantly affected fungal cell morphology and resulted in the accumulation of intracellular vesicles. Deep-sequencing analysis of drug-resistant mutants revealed that four protein products, encoded by genes APL5, COS111, MKK1, and STE2, which are involved in vesicular transport and cell cycle progression, are targeted by BHBM. IMPORTANCE Fungal infections are a significant cause of morbidity and mortality worldwide. Current antifungal drugs suffer from various drawbacks, including toxicity, drug resistance, and narrow spectrum of activity. In this study, we have demonstrated that pharmaceutical inhibition of fungal glucosylceramide presents a new opportunity to treat cryptococcosis and various other fungal infections. In addition to being effective against pathogenic fungi, the compounds discovered in this study were well tolerated by animals and additive to current antifungals. These findings suggest that these drugs might pave the way for the development of a new class of antifungals.
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Affiliation(s)
- Visesato Mor
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, USA
| | - Antonella Rella
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, USA
| | - Amir M Farnoud
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, USA
| | - Ashutosh Singh
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, USA
| | - Mansa Munshi
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, USA
| | - Arielle Bryan
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, USA
| | - Shamoon Naseem
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, USA
| | - James B Konopka
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, USA
| | - Iwao Ojima
- Department of Chemistry and Institute of Chemical Biology and Drug Discovery, Stony Brook University, Stony Brook, New York, USA
| | - Erika Bullesbach
- Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, South Carolina, USA
| | - Alan Ashbaugh
- Department of Veterans Affairs Medical Center, Cincinnati, Ohio, USA
| | | | | | - Margaret Collins
- University of Cincinnati College of Medicine, Cincinnati, Ohio, USA
| | | | - Larry Sallans
- Department of Chemistry, University of Cincinnati, Cincinnati, Ohio, USA
| | - Pankaj B Desai
- Department of Pharmaceutical Sciences, University of Cincinnati, Cincinnati, Ohio, USA
| | - Nathan P Wiederhold
- Department of Pathology, Fungus Testing Laboratory, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
| | - Annette W Fothergill
- Department of Pathology, Fungus Testing Laboratory, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
| | - William R Kirkpatrick
- Division of Infectious Diseases, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
| | - Thomas Patterson
- Division of Infectious Diseases, University of Texas Health Science Center at San Antonio, San Antonio, Texas, USA
| | - Lai Hong Wong
- Department of Pharmaceutical Sciences, University of British Columbia, Vancouver, British Colombia, Canada
| | - Sunita Sinha
- Department of Pharmaceutical Sciences, University of British Columbia, Vancouver, British Colombia, Canada
| | - Guri Giaever
- Department of Pharmaceutical Sciences, University of British Columbia, Vancouver, British Colombia, Canada
| | - Corey Nislow
- Department of Pharmaceutical Sciences, University of British Columbia, Vancouver, British Colombia, Canada
| | - Patrick Flaherty
- Department of Biomedical Engineering, Worcester Polytechnic Institute, Worcester, Massachusetts, USA
| | - Xuewen Pan
- Department of Biochemistry and Molecular Biology, Baylor College of Medicine, Houston, Texas, USA
| | - Gabriele Vargas Cesar
- Instituto de Microbiologia Professor Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Patricia de Melo Tavares
- Instituto de Microbiologia Professor Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Susana Frases
- Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofísica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | | | | | - Chiara Luberto
- Department of Physiology and Biophysics, Stony Brook University, Stony Brook, New York, USA
| | - Leonardo Nimrichter
- Instituto de Microbiologia Professor Paulo de Góes, Universidade Federal do Rio de Janeiro, Rio de Janeiro, Brazil
| | - Maurizio Del Poeta
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, New York, USA
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48
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Tian Y, Zhao GY, Fang W, Xu Q, Tan RX. Δ10(E)-Sphingolipid Desaturase Involved in Fusaruside Mycosynthesis and Stress Adaptation in Fusarium graminearum. Sci Rep 2015; 5:10486. [PMID: 25994332 PMCID: PMC4440215 DOI: 10.1038/srep10486] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 04/15/2015] [Indexed: 12/20/2022] Open
Abstract
Sphingolipids are biologically important and structurally distinct cell membrane components. Fusaruside (1) is a 10,11-unsaturated immunosuppressive fungal sphingolipid with medical potentials for treating liver injury and colitis, but its poor natural abundance bottlenecks its druggability. Here, fusaruside is clarified biosynthetically, and its efficacy-related 10,11-double bond can be generated under the regioselective catalysis of an unprecedented Δ10(E)-sphingolipid desaturase (Δ10(E)-SD). Δ10(E)-SD shares 17.7% amino acid sequence similarity with a C9-unmethylated Δ10-sphingolipid desaturase derived from a marine diatom, and 55.7% with Δ8(E)-SD from Fusarium graminearum. Heterologous expression of Δ10(E)-SD in Pichia pastoris has been established to facilitate a reliable generation of 1 through the Δ10(E)-SD catalyzed desaturation of cerebroside B (2), an abundant fungal sphingolipid. Site directed mutageneses show that the conserved histidines of Δ10(E)-SD are essential for the 10,11-desaturation catalysis, which is also preconditioned by the C9-methylation of the substrate. Moreover, Δ10(E)-SD confers improved survival and faster growth to fungal strains at low temperature and high salinity, in parallel with to higher contents of 1 in the mycelia. Collectively, the investigation describes a new Δ10(E)-sphingolipid desaturase with its heterologous expression fundamentalizing a biotechnological supply of 1, and eases the follow-up clarification of the immunosuppression and stress-tolerance mechanism.
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Affiliation(s)
- Yuan Tian
- Institute of Functional Biomolecules, State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210093, P. R. China
| | - Guo Y. Zhao
- Institute of Functional Biomolecules, State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210093, P. R. China
| | - Wei Fang
- Institute of Functional Biomolecules, State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210093, P. R. China
| | - Qiang Xu
- Institute of Functional Biomolecules, State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210093, P. R. China
| | - Ren X. Tan
- Institute of Functional Biomolecules, State Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing 210093, P. R. China
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49
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The Granuloma Response Controlling Cryptococcosis in Mice Depends on the Sphingosine Kinase 1-Sphingosine 1-Phosphate Pathway. Infect Immun 2015; 83:2705-13. [PMID: 25895971 DOI: 10.1128/iai.00056-15] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Accepted: 04/13/2015] [Indexed: 12/31/2022] Open
Abstract
Cryptococcus neoformans is a fungal pathogen that causes pulmonary infections, which may progress into life-threatening meningitis. In commonly used mouse models of C. neoformans infections, fungal cells are not contained in the lungs, resulting in dissemination to the brain. We have previously reported the generation of an engineered C. neoformans strain (C. neoformans Δgcs1) which can be contained in lung granulomas in the mouse model and have shown that granuloma formation is dependent upon the enzyme sphingosine kinase 1 (SK1) and its product, sphingosine 1-phosphate (S1P). In this study, we have used four mouse models, CBA/J and C57BL6/J (both immunocompetent), Tgε26 (an isogenic strain of strain CBA/J lacking T and NK cells), and SK(-/-) (an isogenic strain of strain C57BL6/J lacking SK1), to investigate how the granulomatous response and SK1-S1P pathway are interrelated during C. neoformans infections. S1P and monocyte chemotactic protein-1 (MCP-1) levels were significantly elevated in the bronchoalveolar lavage fluid of all mice infected with C. neoformans Δgcs1 but not in mice infected with the C. neoformans wild type. SK1(-/-) mice did not show elevated levels of S1P or MCP-1. Primary neutrophils isolated from SK1(-/-) mice showed impaired antifungal activity that could be restored by the addition of extracellular S1P. In addition, high levels of tumor necrosis factor alpha were found in the mice infected with C. neoformans Δgcs1 in comparison to the levels found in mice infected with the C. neoformans wild type, and their levels were also dependent on the SK1-S1P pathway. Taken together, these results suggest that the SK1-S1P pathway promotes host defense against C. neoformans infections by regulating cytokine levels, promoting extracellular killing by phagocytes, and generating a granulomatous response.
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50
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Farnoud AM, Toledo AM, Konopka JB, Del Poeta M, London E. Raft-like membrane domains in pathogenic microorganisms. CURRENT TOPICS IN MEMBRANES 2015; 75:233-68. [PMID: 26015285 DOI: 10.1016/bs.ctm.2015.03.005] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
The lipid bilayer of the plasma membrane is thought to be compartmentalized by the presence of lipid-protein microdomains. In eukaryotic cells, microdomains composed of sterols and sphingolipids, commonly known as lipid rafts, are believed to exist, and reports on the presence of sterol- or protein-mediated microdomains in bacterial cell membranes are also appearing. Despite increasing attention, little is known about microdomains in the plasma membrane of pathogenic microorganisms. This review attempts to provide an overview of the current state of knowledge of lipid rafts in pathogenic fungi and bacteria. The current literature on characterization of microdomains in pathogens is reviewed, and their potential role in growth, pathogenesis, and drug resistance is discussed. Better insight into the structure and function of membrane microdomains in pathogenic microorganisms might lead to a better understanding of their pathogenesis and development of raft-mediated approaches for therapy.
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Affiliation(s)
- Amir M Farnoud
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY, USA
| | - Alvaro M Toledo
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY, USA
| | - James B Konopka
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY, USA
| | - Maurizio Del Poeta
- Department of Molecular Genetics and Microbiology, Stony Brook University, Stony Brook, NY, USA
| | - Erwin London
- Department of Biochemistry and Cell Biology, Stony Brook University, Stony Brook, NY, USA
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