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Cheng A, Zhang H, Chen B, Zheng S, Wang H, Shi Y, You S, Li M, Jiang L. Modulation of autophagy as a therapeutic strategy for Toxoplasma gondii infection. Front Cell Infect Microbiol 2022; 12:902428. [PMID: 36093185 PMCID: PMC9448867 DOI: 10.3389/fcimb.2022.902428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Accepted: 08/05/2022] [Indexed: 12/05/2022] Open
Abstract
Toxoplasma gondii infection is a severe health threat that endangers billions of people worldwide. T. gondii utilizes the host cell membrane to form a parasitophorous vacuole (PV), thereby fully isolating itself from the host cell cytoplasm and making intracellular clearance difficult. PV can be targeted and destroyed by autophagy. Autophagic targeting results in T. gondii killing via the fusion of autophagosomes and lysosomes. However, T. gondii has developed many strategies to suppress autophagic targeting. Accordingly, the interplay between host cell autophagy and T. gondii is an emerging area with important practical implications. By promoting the canonical autophagy pathway or attenuating the suppression of autophagic targeting, autophagy can be effectively utilized in the development of novel therapeutic strategies against T gondii. Here, we have illustrated the complex interplay between host cell mediated autophagy and T. gondii. Different strategies to promote autophagy in order to target the parasite have been elucidated. Besides, we have analyzed some potential new drug molecules from the DrugBank database using bioinformatics tools, which can modulate autophagy. Various challenges and opportunities focusing autophagy mediated T. gondii clearance have been discussed, which will provide new insights for the development of novel drugs against the parasite.
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Affiliation(s)
- Ao Cheng
- Department of Parasitology, Xiangya School of Medicine, Central South University, Changsha, China
| | - Huanan Zhang
- Department of Parasitology, Xiangya School of Medicine, Central South University, Changsha, China
| | - Baike Chen
- Department of Parasitology, Xiangya School of Medicine, Central South University, Changsha, China
| | - Shengyao Zheng
- Department of Parasitology, Xiangya School of Medicine, Central South University, Changsha, China
| | - Hongyi Wang
- Department of Parasitology, Xiangya School of Medicine, Central South University, Changsha, China
| | - Yijia Shi
- Department of Parasitology, Xiangya School of Medicine, Central South University, Changsha, China
| | - Siyao You
- Department of Parasitology, Xiangya School of Medicine, Central South University, Changsha, China
| | - Ming Li
- Department of Immunology, Xiangya School of Medicine, Central South University, Changsha, China
- *Correspondence: Liping Jiang, ; Ming Li,
| | - Liping Jiang
- Department of Parasitology, Xiangya School of Medicine, Central South University, Changsha, China
- China-Africa Research Center of Infectious Diseases, Xiangya School of Medicine, Central South University, Changsha, China
- *Correspondence: Liping Jiang, ; Ming Li,
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Cova M, López-Gutiérrez B, Artigas-Jerónimo S, González-Díaz A, Bandini G, Maere S, Carretero-Paulet L, Izquierdo L. The Apicomplexa-specific glucosamine-6-phosphate N-acetyltransferase gene family encodes a key enzyme for glycoconjugate synthesis with potential as therapeutic target. Sci Rep 2018; 8:4005. [PMID: 29507322 PMCID: PMC5838249 DOI: 10.1038/s41598-018-22441-3] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 02/22/2018] [Indexed: 02/06/2023] Open
Abstract
Apicomplexa form a phylum of obligate parasitic protozoa of great clinical and veterinary importance. These parasites synthesize glycoconjugates for their survival and infectivity, but the enzymatic steps required to generate the glycosylation precursors are not completely characterized. In particular, glucosamine-phosphate N-acetyltransferase (GNA1) activity, needed to produce the essential UDP-N-acetylglucosamine (UDP-GlcNAc) donor, has not been identified in any Apicomplexa. We scanned the genomes of Plasmodium falciparum and representatives from six additional main lineages of the phylum for proteins containing the Gcn5-related N-acetyltransferase (GNAT) domain. One family of GNAT-domain containing proteins, composed by a P. falciparum sequence and its six apicomplexan orthologs, rescued the growth of a yeast temperature-sensitive GNA1 mutant. Heterologous expression and in vitro assays confirmed the GNA1 enzymatic activity in all lineages. Sequence, phylogenetic and synteny analyses suggest an independent origin of the Apicomplexa-specific GNA1 family, parallel to the evolution of a different GNA1 family in other eukaryotes. The inability to disrupt an otherwise modifiable gene target suggests that the enzyme is essential for P. falciparum growth. The relevance of UDP-GlcNAc for parasite viability, together with the independent evolution and unique sequence features of Apicomplexa GNA1, highlights the potential of this enzyme as a selective therapeutic target against apicomplexans.
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Affiliation(s)
- Marta Cova
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
| | - Borja López-Gutiérrez
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
| | - Sara Artigas-Jerónimo
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
| | - Aida González-Díaz
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain
| | - Giulia Bandini
- Department of Molecular and Cell Biology, Boston University Goldman School of Dental Medicine, Boston, USA
| | - Steven Maere
- Ghent University, Department of Plant Biotechnology and Bioinformatics, B-9052, Ghent, Belgium
- VIB Center for Plant Systems Biology, B-9052, Ghent, Belgium
- Bioinformatics Institute Ghent, Ghent University, B-9052, Ghent, Belgium
| | - Lorenzo Carretero-Paulet
- Ghent University, Department of Plant Biotechnology and Bioinformatics, B-9052, Ghent, Belgium.
- VIB Center for Plant Systems Biology, B-9052, Ghent, Belgium.
- Bioinformatics Institute Ghent, Ghent University, B-9052, Ghent, Belgium.
| | - Luis Izquierdo
- ISGlobal, Barcelona Ctr. Int. Health Res. (CRESIB), Hospital Clínic - Universitat de Barcelona, Barcelona, Spain.
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Aquino-Gil MO, Kupferschmid M, Shams-Eldin H, Schmidt J, Yamakawa N, Mortuaire M, Krzewinski F, Hardivillé S, Zenteno E, Rolando C, Bray F, Pérez Campos E, Dubremetz JF, Perez-Cervera Y, Schwarz RT, Lefebvre T. Apart From Rhoptries, Identification of Toxoplasma gondii's O-GlcNAcylated Proteins Reinforces the Universality of the O-GlcNAcome. Front Endocrinol (Lausanne) 2018; 9:450. [PMID: 30177911 PMCID: PMC6109639 DOI: 10.3389/fendo.2018.00450] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Accepted: 07/20/2018] [Indexed: 11/23/2022] Open
Abstract
O-linked β-N-acetylglucosaminylation or O-GlcNAcylation is a widespread post-translational modification that belongs to the large and heterogeneous group of glycosylations. The functions managed by O-GlcNAcylation are diverse and include regulation of transcription, replication, protein's fate, trafficking, and signaling. More and more evidences tend to show that deregulations in the homeostasis of O-GlcNAcylation are involved in the etiology of metabolic diseases, cancers and neuropathologies. O-GlcNAc transferase or OGT is the enzyme that transfers the N-acetylglucosamine residue onto target proteins confined within the cytosolic and nuclear compartments. A form of OGT was predicted for Toxoplasma and recently we were the first to show evidence of O-GlcNAcylation in the apicomplexans Toxoplasma gondii and Plasmodium falciparum. Numerous studies have explored the O-GlcNAcome in a wide variety of biological models but very few focus on protists. In the present work, we used enrichment on sWGA-beads and immunopurification to identify putative O-GlcNAcylated proteins in Toxoplasma gondii. Many of the proteins found to be O-GlcNAcylated were originally described in higher eukaryotes and participate in cell shape organization, response to stress, protein synthesis and metabolism. In a more original way, our proteomic analyses, confirmed by sWGA-enrichment and click-chemistry, revealed that rhoptries, proteins necessary for invasion, are glycosylated. Together, these data show that regardless of proteins strictly specific to organisms, O-GlcNAcylated proteins are rather similar among living beings.
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Affiliation(s)
- Moyira Osny Aquino-Gil
- Univ. Lille, CNRS, UMR 8576, UGSF, Unité de Glycobiologie Structurale et Fonctionnelle, Lille, France
- Instituto Tecnológico de Oaxaca, Tecnológico Nacional de México, Oaxaca, Mexico
- Centro de Investigación Facultad de Medicina UNAM-UABJO, Facultad de Odontología, Universidad Autónoma Benito Juárez de Oaxaca, Oaxaca, Mexico
| | - Mattis Kupferschmid
- Laboratory of Parasitology, Institute for Virology, Philipps-University, Marburg, Germany
| | - Hosam Shams-Eldin
- Laboratory of Parasitology, Institute for Virology, Philipps-University, Marburg, Germany
| | - Jörg Schmidt
- Laboratory of Parasitology, Institute for Virology, Philipps-University, Marburg, Germany
| | - Nao Yamakawa
- Univ. Lille, CNRS, UMR 8576, UGSF, Unité de Glycobiologie Structurale et Fonctionnelle, Lille, France
| | - Marlène Mortuaire
- Univ. Lille, CNRS, UMR 8576, UGSF, Unité de Glycobiologie Structurale et Fonctionnelle, Lille, France
| | - Frédéric Krzewinski
- Univ. Lille, CNRS, UMR 8576, UGSF, Unité de Glycobiologie Structurale et Fonctionnelle, Lille, France
| | - Stéphan Hardivillé
- Univ. Lille, CNRS, UMR 8576, UGSF, Unité de Glycobiologie Structurale et Fonctionnelle, Lille, France
| | - Edgar Zenteno
- Facultad de Medicina de la Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - Christian Rolando
- CNRS, MSAP USR 3290, FR 3688 FRABIO, FR 2638 Institut Eugène-Michel Chevreul, Université de Lille, Lille, France
| | - Fabrice Bray
- CNRS, MSAP USR 3290, FR 3688 FRABIO, FR 2638 Institut Eugène-Michel Chevreul, Université de Lille, Lille, France
| | - Eduardo Pérez Campos
- Instituto Tecnológico de Oaxaca, Tecnológico Nacional de México, Oaxaca, Mexico
- Centro de Investigación Facultad de Medicina UNAM-UABJO, Facultad de Odontología, Universidad Autónoma Benito Juárez de Oaxaca, Oaxaca, Mexico
| | - Jean-François Dubremetz
- Unité Mixte de Recherche 5235, Dynamique des Interactions Membranaires Normales et Pathologiques, Université Montpellier, Montpellier, France
| | - Yobana Perez-Cervera
- Instituto Tecnológico de Oaxaca, Tecnológico Nacional de México, Oaxaca, Mexico
- Centro de Investigación Facultad de Medicina UNAM-UABJO, Facultad de Odontología, Universidad Autónoma Benito Juárez de Oaxaca, Oaxaca, Mexico
| | - Ralph T. Schwarz
- Univ. Lille, CNRS, UMR 8576, UGSF, Unité de Glycobiologie Structurale et Fonctionnelle, Lille, France
- Laboratory of Parasitology, Institute for Virology, Philipps-University, Marburg, Germany
| | - Tony Lefebvre
- Univ. Lille, CNRS, UMR 8576, UGSF, Unité de Glycobiologie Structurale et Fonctionnelle, Lille, France
- *Correspondence: Tony Lefebvre
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Extracellular Toxoplasma gondii tachyzoites metabolize and incorporate unnatural sugars into cellular proteins. Microbes Infect 2015; 18:199-210. [PMID: 26687036 DOI: 10.1016/j.micinf.2015.11.004] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2014] [Revised: 11/12/2015] [Accepted: 11/13/2015] [Indexed: 11/20/2022]
Abstract
Toxoplasma gondii is an obligate intracellular parasite that infects all nucleated cell types in diverse warm-blooded organisms. Many of the surface antigens and effector molecules secreted by the parasite during invasion and intracellular growth are modified by glycans. Glycosylated proteins in the nucleus and cytoplasm have also been reported. Despite their prevalence, the complete inventory and biological significance of glycosylated proteins in Toxoplasma remain unknown. In this study, we aimed to globally profile parasite glycoproteins using a bioorthogonal chemical reporter strategy. This strategy involves the metabolic incorporation of unnatural functional groups (i.e., "chemical reporters") into Toxoplasma glycans, followed by covalent labeling with visual probes or affinity tags. The two-step approach enables the visualization and identification of newly biosynthesized glycoconjugates in the parasite. Using a buffer that mimics intracellular conditions, extracellular Toxoplasma tachyzoites were found to metabolize and incorporate unnatural sugars (equipped with bioorthogonal functional groups) into diverse proteins. Covalent chemistries were used to visualize and retrieve these labeled structures. Subsequent mass spectrometry analysis revealed 89 unique proteins. This survey identified novel proteins as well as previously characterized proteins from lectin affinity analyses.
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Gómez de León CT, Díaz Martín RD, Mendoza Hernández G, González Pozos S, Ambrosio JR, Mondragón Flores R. Proteomic characterization of the subpellicular cytoskeleton of Toxoplasma gondii tachyzoites. J Proteomics 2014; 111:86-99. [DOI: 10.1016/j.jprot.2014.03.008] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2013] [Revised: 02/27/2014] [Accepted: 03/07/2014] [Indexed: 01/09/2023]
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6
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Targeting lipid biosynthesis and salvage in apicomplexan parasites for improved chemotherapies. Nat Rev Microbiol 2013; 11:823-35. [DOI: 10.1038/nrmicro3139] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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7
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Alley WR, Mann BF, Novotny MV. High-sensitivity analytical approaches for the structural characterization of glycoproteins. Chem Rev 2013; 113:2668-732. [PMID: 23531120 PMCID: PMC3992972 DOI: 10.1021/cr3003714] [Citation(s) in RCA: 239] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- William R. Alley
- Department of Chemistry, Indiana University, Bloomington, Indiana, United States
- National Center for Glycomics and Glycoproteomics, Indiana University, Bloomington, Indiana, United States
| | - Benjamin F. Mann
- Department of Chemistry, Indiana University, Bloomington, Indiana, United States
- National Center for Glycomics and Glycoproteomics, Indiana University, Bloomington, Indiana, United States
| | - Milos V. Novotny
- Department of Chemistry, Indiana University, Bloomington, Indiana, United States
- National Center for Glycomics and Glycoproteomics, Indiana University, Bloomington, Indiana, United States
- Indiana University School of Medicine, Indiana University, Indianapolis, Indiana, United States
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8
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Azzouz N, Kamena F, Laurino P, Kikkeri R, Mercier C, Cesbron-Delauw MF, Dubremetz JF, De Cola L, Seeberger PH. Toxoplasma gondii secretory proteins bind to sulfated heparin structures. Glycobiology 2012; 23:106-20. [DOI: 10.1093/glycob/cws134] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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9
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Khosroshahi KH, Ghaffarifar F, Sharifi Z, D'Souza S, Dalimi A, Hassan ZM, Khoshzaban F. Comparing the effect of IL-12 genetic adjuvant and alum non-genetic adjuvant on the efficiency of the cocktail DNA vaccine containing plasmids encoding SAG-1 and ROP-2 of Toxoplasma gondii. Parasitol Res 2012; 111:403-11. [PMID: 22350714 DOI: 10.1007/s00436-012-2852-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2010] [Accepted: 02/02/2012] [Indexed: 11/28/2022]
Abstract
Various methods are available for enhancing the potency of DNA vaccines, including employment of different forms of adjuvant. The current study was carried out to evaluate and compare the effects of genetic and non-genetic adjuvants on the immune response stimulated by DNA vaccine. Thus, two adjuvants, IL-12 (genetic adjuvant) and aluminum hydroxide (alum, non-genetic adjuvant), were used with cocktail DNA vaccine containing plasmids encoding complete rhoptry antigen 2 (ROP-2) and surface major antigen 1 (SAG-1) of Toxoplasma gondii. The efficacy of pcROP2+pcSAG1 in stimulation of the immune response against toxoplasmosis with and without adjuvant was evaluated in female BALB/c mice by measuring the level of total IgG antibody and cytokines. The results obtained indicated that after challenging the mice with the fatal RH strain of T. gondii, the survival rates of mice immunized with pcROP2+pcSAG1 (DNA cocktail), pcSAG1+pcROP2+alum, and pcSAG1+pcROP2+IL-12 were significantly greater than that of the control groups (p<0.05). Moreover, measurement of total IgG antibody indicated the significant difference between the control and experimental groups (p<0.05). Finally, the results obtained by measurement of cytokines (IFN-γ and IL-4) showed high levels of IFN-γ and low levels of IL-4 in groups vaccinated with pcROP2+pcSAG1 (DNA cocktail), pcSAG1+pcROP2+alum, and pcSAG1+pcROP2+IL-12 as the experiment groups, in comparison with the controls groups (PBS, pc-DNA3, alum+PBS, and pCAGGS-IL-12+pcDNA3). The results of the study showed that use of adjuvants (IL-12 and alum) coincident with DNA cocktail leads to significant change in the survival rates of the experiment groups in comparison with control groups. Also, there is no significant difference between adjuvants to induce immune responses.
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Debierre-Grockiego F, Schwarz RT. Immunological reactions in response to apicomplexan glycosylphosphatidylinositols. Glycobiology 2010; 20:801-11. [PMID: 20378610 DOI: 10.1093/glycob/cwq038] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Apicomplexan protozoa are a phylum of parasites that includes pathogens such as Plasmodium, the causative agent of the most severe form of malaria responsible for almost 1 million deaths per year and Toxoplasma gondii causing toxoplasmosis, a disease leading to cerebral meningitis in immunocompromised individuals or to abortion in farm animals or in women that are infected for the first time during pregnancy. The initial immune reactions developed by the host are similar in response to an infection with Plasmodium and Toxoplasma in the sense that the same cells of the innate immune system are stimulated to produce inflammatory cytokines. The glycosylphosphatidylinositol (GPI) anchor is the major carbohydrate modification in parasite proteins and the GPIs are essential for parasite survival. Two immediate GPI precursors with the structures ethanolamine phosphate-6(Manalpha1-2)Manalpha1-2Manalpha1-6Manalpha1-4GlcN-PI and ethanolamine phosphate-6Manalpha1-2Manalpha1-6Man-alpha1-4-GlcN-PI are synthesized by P. falciparum. Two main structures are synthesized by T. gondii: ethanolamine phosphate-6Manalpha1-2Manalpha1-6(GalNAcbeta1-4)Manalpha1-4GlcN-PI and ethanolamine phosphate-6Manalpha1-2Manalpha1-6(Glcalpha1-4GalNAcbeta1-4)Manalpha1-4GlcN-PI. This review describes the biosynthesis of the apicomplexan GPIs and their role in the activation of the host immune system.
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Affiliation(s)
- Françoise Debierre-Grockiego
- UMR Université-INRA 0483, Immunologie Parasitaire Vaccinologie et Biothérapies anti-infectieuses, UFR Sciences Pharmaceutiques, 31 avenue Monge, 37200 Tours, France
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Chapter 9 GPIs of Apicomplexan Protozoa. ACTA ACUST UNITED AC 2009. [DOI: 10.1016/s1874-6047(09)26009-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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12
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Garénaux E, Shams-Eldin H, Chirat F, Bieker U, Schmidt J, Michalski JC, Cacan R, Guérardel Y, Schwarz RT. The Dual Origin of Toxoplasma gondii N-Glycans. Biochemistry 2008; 47:12270-6. [DOI: 10.1021/bi801090a] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Estelle Garénaux
- Unité de Glycobiologie Structurale et Fonctionnelle, UMR 8576 CNRS, Université des Sciences et Technologies de Lille, 59655 Villeneuve d’Ascq cedex, France, and Institut für Virologie, AG Parasitologie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 2, 35043 Marburg, Germany
| | - Hosam Shams-Eldin
- Unité de Glycobiologie Structurale et Fonctionnelle, UMR 8576 CNRS, Université des Sciences et Technologies de Lille, 59655 Villeneuve d’Ascq cedex, France, and Institut für Virologie, AG Parasitologie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 2, 35043 Marburg, Germany
| | - Frederic Chirat
- Unité de Glycobiologie Structurale et Fonctionnelle, UMR 8576 CNRS, Université des Sciences et Technologies de Lille, 59655 Villeneuve d’Ascq cedex, France, and Institut für Virologie, AG Parasitologie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 2, 35043 Marburg, Germany
| | - Ulrike Bieker
- Unité de Glycobiologie Structurale et Fonctionnelle, UMR 8576 CNRS, Université des Sciences et Technologies de Lille, 59655 Villeneuve d’Ascq cedex, France, and Institut für Virologie, AG Parasitologie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 2, 35043 Marburg, Germany
| | - Jörg Schmidt
- Unité de Glycobiologie Structurale et Fonctionnelle, UMR 8576 CNRS, Université des Sciences et Technologies de Lille, 59655 Villeneuve d’Ascq cedex, France, and Institut für Virologie, AG Parasitologie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 2, 35043 Marburg, Germany
| | - Jean-Claude Michalski
- Unité de Glycobiologie Structurale et Fonctionnelle, UMR 8576 CNRS, Université des Sciences et Technologies de Lille, 59655 Villeneuve d’Ascq cedex, France, and Institut für Virologie, AG Parasitologie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 2, 35043 Marburg, Germany
| | - René Cacan
- Unité de Glycobiologie Structurale et Fonctionnelle, UMR 8576 CNRS, Université des Sciences et Technologies de Lille, 59655 Villeneuve d’Ascq cedex, France, and Institut für Virologie, AG Parasitologie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 2, 35043 Marburg, Germany
| | - Yann Guérardel
- Unité de Glycobiologie Structurale et Fonctionnelle, UMR 8576 CNRS, Université des Sciences et Technologies de Lille, 59655 Villeneuve d’Ascq cedex, France, and Institut für Virologie, AG Parasitologie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 2, 35043 Marburg, Germany
| | - Ralph T. Schwarz
- Unité de Glycobiologie Structurale et Fonctionnelle, UMR 8576 CNRS, Université des Sciences et Technologies de Lille, 59655 Villeneuve d’Ascq cedex, France, and Institut für Virologie, AG Parasitologie, Philipps-Universität Marburg, Hans-Meerwein-Strasse 2, 35043 Marburg, Germany
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13
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Harvey DJ. Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: an update covering the period 2001-2002. MASS SPECTROMETRY REVIEWS 2008; 27:125-201. [PMID: 18247413 DOI: 10.1002/mas.20157] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
This review is the second update of the original review on the application of MALDI mass spectrometry to the analysis of carbohydrates and glycoconjugates that was published in 1999. It covers fundamental aspects of the technique as applied to carbohydrates, fragmentation of carbohydrates, studies of specific carbohydrate types such as those from plant cell walls and those attached to proteins and lipids, studies of glycosyl-transferases and glycosidases, and studies where MALDI has been used to monitor products of chemical synthesis. Use of the technique shows a steady annual increase at the expense of older techniques such as FAB. There is an increasing emphasis on its use for examination of biological systems rather than on studies of fundamental aspects and method development and this is reflected by much of the work on applications appearing in tabular form.
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Affiliation(s)
- David J Harvey
- Department of Biochemistry, Oxford Glycobiology Institute, South Parks Road, Oxford OX1 3QU, UK.
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14
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Kato M, Claveria FG, Maki Y, Sanda K, Tanaka T, Omata Y, Nagasawa H, Suzuki N. Reactivity of Synthetic SAG1 (p30) Peptide Sequences with RH, S273 and Beverley Strain-Induced Anti- Toxoplasma gondii Antibodies. Pathobiology 2007; 74:50-6. [PMID: 17496433 DOI: 10.1159/000101051] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2006] [Accepted: 12/07/2006] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVES We compared the reactivity of IgG1 and IgG2a antibodies in mouse sera after infection with virulent RH and low-virulent S273 and Beverley strains of Toxoplasma gondii against RH SAG1 recombinant p30 (rp30) and synthetic SAG1 peptides. METHODS Infected mouse serum samples were collected 9 days after infection, and the level of total IgG, IgG1 and IgG2a against the RH SAG1 rp30 protein and twenty peptides of the RH SAG1 protein were assessed. The glycosylphosphatidylinositol (GPI) modification site, the hydrophilic-hydrophobic structure, the transmembrane region and the secondary structure of the SAG1 sequence of virulent and low-virulent strains were analyzed using software. RESULTS The virulent strain-infected mice produced a higher level of IgG1 but a lower IgG2a against the rp30 antigen, while the low-virulent strain-infected mice produced a higher level of IgG2a than the virulent strain. The difference in the secondary structure of SAG1 protein between the virulent and low-virulent strain was largely confined to amino acid positions 291-336, showing mutations and GPI anchor site. CONCLUSION The difference in the reactivity of IgG against the rp30 antigen and synthetic peptides between virulent and low-virulent strains points to the importance of the primary and secondary structure assumed by antigens in the activation of Th cells and, subsequently, in the induction of IgG and its subclasses.
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Affiliation(s)
- M Kato
- Obihiro University, Obihiro, Japan
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15
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Kimmel J, Smith TK, Azzouz N, Gerold P, Seeber F, Lingelbach K, Dubremetz JF, Schwarz RT. Membrane topology and transient acylation of Toxoplasma gondii glycosylphosphatidylinositols. EUKARYOTIC CELL 2007; 5:1420-9. [PMID: 16896225 PMCID: PMC1539143 DOI: 10.1128/ec.00078-06] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Using hypotonically permeabilized Toxoplasma gondii tachyzoites, we investigated the topology of the free glycosylphosphatidylinositols (GPIs) within the endoplasmic reticulum (ER) membrane. The morphology and permeability of parasites were checked by electron microscopy and release of a cytosolic protein. The membrane integrity of organelles (ER and rhoptries) was checked by protease protection assays. In initial experiments, GPI biosynthetic intermediates were labeled with UDP-[6-(3)H]GlcNAc in permeabilized parasites, and the transmembrane distribution of the radiolabeled lipids was probed with phosphatidylinositol-specific phospholipase C (PI-PLC). A new early intermediate with an acyl modification on the inositol was identified, indicating that inositol acylation also occurs in T. gondii. A significant portion of the early GPI intermediates (GlcN-PI and GlcNAc-PI) could be hydrolyzed following PI-PLC treatment, indicating that these glycolipids are predominantly present in the cytoplasmic leaflet of the ER. Permeabilized T. gondii parasites labeled with either GDP-[2-(3)H]mannose or UDP-[6-(3)H]glucose showed that the more mannosylated and side chain (Glc-GalNAc)-modified GPI intermediates are also preferentially localized in the cytoplasmic leaflet of the ER.
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Affiliation(s)
- Jürgen Kimmel
- Institut für Virologie, Zentrum für Hygiene und Medizinische Mikrobiologie, Philipps-Universität, Robert-Koch-Strasse 17, 35037 Marburg, Germany
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16
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Abstract
As an actively dividing organism, the intracellular parasite Toxoplasma gondii must adjust the size and composition of its membranes in order to accommodate changes due to housekeeping activities, to commit division and in fine to produce new viable progenies. Lipid inventory of T. gondii reveals that the biological membranes of this parasite are composed of a complex mixture of neutral and polar lipids. After examination of the origin of T. gondii membrane lipids, three categories of lipids can be described: (i) lipids scavenged by T. gondii from the host cell; (ii) lipids synthesized in large amounts by the parasite, independently from its host cell; and (iii) lipids produced de novo by the parasite, but whose synthesis does not come close to satisfying the entire parasite's needs. These latter must be adeptly acquired from the host environment. To this end, T. gondii diverts a large variety of lipid precursors from host cytoplasm and efficiently manufacture them into complex lipids. This rather remarkable reliance on host lipid resources for parasite survival opens new avenues to restrict parasite growth. Indeed, parasite starvation can be induced upon deprivation from essential host lipids. Lipid analogues with anti-proliferative properties are voraciously taken up by the parasites, which results in parasite membrane defects, and ultimately death.
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Affiliation(s)
- Isabelle Coppens
- Department of Molecular Microbiology and Immunology, Johns Hopkins University Bloomberg School of Public Health, 615 N. Wolfe Street, Baltimore, MD 21205, USA.
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17
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Azzouz N, Shams-Eldin H, Niehus S, Debierre-Grockiego F, Bieker U, Schmidt J, Mercier C, Delauw MF, Dubremetz JF, Smith TK, Schwarz RT. Toxoplasma gondii grown in human cells uses GalNAc-containing glycosylphosphatidylinositol precursors to anchor surface antigens while the immunogenic Glc–GalNAc-containing precursors remain free at the parasite cell surface. Int J Biochem Cell Biol 2006; 38:1914-25. [PMID: 16822699 DOI: 10.1016/j.biocel.2006.05.006] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2006] [Revised: 05/10/2006] [Accepted: 05/15/2006] [Indexed: 10/24/2022]
Abstract
Toxoplasma gondii is a ubiquitous parasite that infects nearly all warm-blooded animals. Developmental switching in T. gondii, from the virulent tachyzoite to the relatively quiescent bradyzoite stage, is responsible for the disease propagation after alteration of the immune status of the carrier. The redifferentiation event is characterized by an over expression of a tachyzoite specific set of glycosylphosphatidylinositol anchored surface antigens and free GPIs. T. gondii grown in animal cells uses two glycosylphosphatidylinositol precursors to anchor the parasite surface proteins. The first form has an N-acetylgalactosamine residue bound to a conserved three-mannosyl core glycan, while the second structure contains an additional terminal glucose linked to the N-acetylgalactosamine side branch. Sera from persons infected with T. gondii reacted only with the glucose-N-acetylgalactosamine-containing structure. Here we report that T. gondii cultured in human cells uses predominantly the N-acetylgalactosamine-containing structure to anchor the parasite surface antigens. On the other hand, glycosylphosphatidylinositol structures having an additional terminal glucose are found exclusively on the parasite cell surface as free glycolipids participating in the production of cytokines that are implicated in the pathogenesis of T. gondii. We also provide evidence that such free glycosylphosphatidylinositols are restricted mainly to the lipid microdomains in the parasite cell surface membrane and mostly associated with proteins involved in the parasite motility as well as invasion of the host cell.
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Affiliation(s)
- Nahid Azzouz
- Laboratory for Organic Chemistry, Swiss Federal Institute of Technology, ETH Zurich, HCI E328, Wolfgang-Pauli-Strasse 10, 8093 Zurich, Switzerland.
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18
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Shams-Eldin H, Blaschke T, Anhlan D, Niehus S, Müller J, Azzouz N, Schwarz RT. High-level expression of the Toxoplasma gondii STT3 gene is required for suppression of the yeast STT3 gene mutation. Mol Biochem Parasitol 2005; 143:6-11. [PMID: 15936094 DOI: 10.1016/j.molbiopara.2005.04.008] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2005] [Revised: 03/30/2005] [Accepted: 04/25/2005] [Indexed: 11/16/2022]
Abstract
N-linked glycosylation is the most frequent modification of secretory proteins. The central reaction of this process in eukaryotic cells is catalyzed by the hetero-oligomeric protein complex oligosaccharyltransferase (OST). The gene STT3 gene encodes a protein, which is the most conserved among the components of the OST. In this report, we describe the isolation and functional characterization of a STT3 homologue from Toxoplasma gondii. The topology of the TgStt3p is similar to that of the yeast Stt3p with 47% identity. We demonstrate that high level expression of the homologues gene is required to completely suppress the defect caused by a stt3 mutation in yeast, suggesting that homologous Stt3 proteins can serve analogous functions in distantly related eukaryotic cells regardless of their degree of conservation.
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Affiliation(s)
- Hosam Shams-Eldin
- Institute for Virology, Medical Center for Hygiene and Medical Microbiology, Philipps University Marburg, Robert Koch Strasse 17, DE-35037 Marburg, Germany
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19
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Debierre-Grockiego F, Azzouz N, Schmidt J, Dubremetz JF, Geyer H, Geyer R, Weingart R, Schmidt RR, Schwarz RT. Roles of glycosylphosphatidylinositols of Toxoplasma gondii. Induction of tumor necrosis factor-alpha production in macrophages. J Biol Chem 2003; 278:32987-93. [PMID: 12815041 DOI: 10.1074/jbc.m304791200] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Toxoplasma gondii is a ubiquitous parasitic protozoan, which causes congenital infectious diseases as well as severe encephalitis, a major cause of death among immune-deficient persons, such as AIDS patients. T. gondii is normally controlled by the immune system of healthy individuals, leading to an asymptomatic infection. T. gondii triggers early cytokine production, which, to a certain extent, protects the host against replication of tachyzoites, the infective form of the parasite. Glycosylphosphatidylinositols (GPIs) constitute a class of glycolipids that have various functions, the most fundamental being to link proteins to eucaryotic cell membranes. GPIs are involved in the pathogenicity of other protozoan parasites and are known to induce tumor necrosis factor-alpha (TNF alpha) production. We show that GPIs highly purified from T. gondii tachyzoites, as well as their core glycans, induce TNF alpha production in macrophages. A chemically synthesized GPI of T. gondii lacking its lipid moiety, GPIa, has the same effect as the natural GPIs, whereas a chemically synthesized molecule with dialkylglycerol instead of diacylglycerol as lipid moiety, GPIb, does not induce TNF alpha production. Moreover, GPIb inhibits the TNF alpha production induced by T. gondii GPI or by GPIa. The core glycan prepared from the two chemically synthesized molecules activates macrophages, showing that the lipid moiety may regulate signaling. Stimulation of macrophages with GPIs of T. gondii results in activation of the transcription factor NF-kappa B, which is inhibited by the chemically synthesized GPIb, suggesting the involvement of NF-kappa B in TNF alpha gene expression. Our results support the idea that T. gondii GPIs are bioactive factors that participate in the production of TNF alpha during toxoplasmal pathogenesis.
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Affiliation(s)
- Françoise Debierre-Grockiego
- Institute for Virology, Medical Center for Hygiene, Philipps University, Robert-Koch-Strasse 17, D-35037 Marburg, Germany.
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20
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Hyun C, Gupta GD, Marsh AE. Sequence comparison of Sarcocystis neurona surface antigen from multiple isolates. Vet Parasitol 2003; 112:11-20. [PMID: 12581581 DOI: 10.1016/s0304-4017(02)00392-8] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Sarcocystis neurona is responsible for equine protozoal myeloencephalitis (EPM) and is phylogenetically closely related to Toxoplasma gondii and Neospora spp. There has been major progress in evaluating immunodominant and surface proteins of T. gondii and Neospora spp.; however, there is a paucity of data on the proteins or genes from S. neurona and S. neurona-like parasites. In this study, using reverse transcription-PCR (RT-PCR) and restriction fragment length polymorphism (RFLP) methods, the surface antigen gene 1 (SAG1) from several isolates was characterized by sequence analysis and evaluated for molecular diagnostic identification. AluI restriction digestion of PCR amplicons of the SAG1 gene verified the sequencing results. The putative SAG1 gene from isolates of S. neurona or S. neurona-like parasites varied from 73 to 100% sequence similarity, whereas the SAG1 gene from isolates of Neospora spp. varied from 96 to 98% sequence similarity.
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Affiliation(s)
- C Hyun
- Department of Veterinary Pathobiology, College of Veterinary Medicine, University of Missouri, Connaway Hall 1600, East Rollins Drive, Columbia, MO 65211, USA
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21
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Meek B, Diepersloot RJ, van Gool T, Speijer D, Peek R. Igm recognition of recombinant Toxoplasma gondii antigens by sera of acutely or latently infected humans. Diagn Microbiol Infect Dis 2003; 45:45-52. [PMID: 12573550 DOI: 10.1016/s0732-8893(02)00476-5] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Clinical non-relevant (CNR) IgM specific for Toxoplasma gondii is responsible for false-positive results in commercially available IgM assays. Using IgM immunoblotting, it is possible to distinguish between IgM in sera of acutely infected (AI) patients and CNR IgM. Especially the combination of staining of a 55 and 30 kD antigen in T.gondii lysate proved useful in this respect. The 55 kD antigen was identified as Rop1, while the 30 kD antigen was confirmed to be Sag1. However, the use of recombinant antigens instead of lysates for diagnostic assays would improve reproducibility. IgM recognized recombinant Rop1, but most CNR sera also had low anti-Rop1 titers. Although purified native Sag1 separated AI and CNR sera very well on immunoblot, IgM did not recognize recombinant Sag1 at all. Clearly, it is difficult to produce a recombinant Sag1 that can be recognized by IgM. Recombinant Rop1 might be suitable as one of the recombinant antigens in an IgM immunoblot assay, but has to be combined with at least one other immunogenic antigen.
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Affiliation(s)
- Bob Meek
- Department of Molecular Immunology, The Netherlands Ophthalmic Research Institute, Amsterdam, The Netherlands
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22
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Smith TK, Crossman A, Paterson MJ, Borissow CN, Brimacombe JS, Ferguson MAJ. Specificities of enzymes of glycosylphosphatidylinositol biosynthesis in Trypanosoma brucei and HeLa cells. J Biol Chem 2002; 277:37147-53. [PMID: 12147686 DOI: 10.1074/jbc.m203371200] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A series of synthetic analogues of d-GlcN alpha 1-6-d-myo-inositol-1-HPO(4)-sn-1,2-dipalmitoylglycerol, consisting of 22 variants of the d-GlcN or lipid components, were tested in trypanosomal and human (HeLa) cell-free systems. The assays measured the abilities of the analogues to act as substrates or inhibitors of the enzymes of glycosylphosphatidylinositol biosynthesis downstream of GlcNAc-phosphatidylinositol (GlcNAc-PI) de-N-acetylase. One compound, 4-deoxy-d-GlcN alpha 1-6-d-myo-inositol-1-HPO(4)-sn-1,2-dipalmitoylglycerol, proved to be an inhibitor of both the trypanosomal and HeLa pathways, whereas 4-O-methyl-d-GlcN alpha 1-6-d-myo-inositol-1-HPO(4)-sn-1,2-dipalmitoylglycerol and the 4'-epimer, d-GalN-alpha1-6-d-myo-inositol-1-HPO(4)-sn-1,2-dipalmitoylglycerol, were neither substrates nor inhibitors. The results with other analogues showed that the 6-OH of the alpha-d-GlcN residue is not required for substrate recognition in the trypanosomal and human pathways, whereas the 3-OH group is essential for both. Parasite-specific recognition of the beta-linked analogue d-GlcN beta 1-6-d-myo-inositol-1-HPO(4)-sn-1,2-dipalmitoylglycerol is striking. This suggests that, like the GlcNAc-PI de-N-acetylase, the trypanosomal glycosylphosphatidylinositol alpha-mannosyltransferases, inositol acyltransferse and ethanolamine phosphate transferase, do not recognize the 2-, 3-, 4-, and 5-OH groups of the d-myo-inositol residue, whereas the human inositol acyltransferase and/or first alpha-mannosyltransferase recognizes one or more of these groups. All of the various lipid analogues tested served as substrates in both the trypanosomal and HeLa cell-free systems, suggesting that a precise lipid structure and stereochemistry are not essential for substrate recognition. However, an analogue containing a single C18:0 alkyl chain in place of sn-1,2-dipalmitoylglycerol proved to be a better substrate in the trypanosomal than in the HeLa cell-free system. These findings should have a bearing on the design of future generations of specific inhibitors of the trypanosomal glycosylphosphatidylinositol biosynthetic pathway.
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Affiliation(s)
- Terry K Smith
- Division of Biological Chemistry & Molecular Microbiology, The School of Life Sciences, University of Dundee, Dundee DD1 5EH, Scotland, United Kingdom
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23
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Wichroski MJ, Melton JA, Donahue CG, Tweten RK, Ward GE. Clostridium septicum alpha-toxin is active against the parasitic protozoan Toxoplasma gondii and targets members of the SAG family of glycosylphosphatidylinositol-anchored surface proteins. Infect Immun 2002; 70:4353-61. [PMID: 12117945 PMCID: PMC128134 DOI: 10.1128/iai.70.8.4353-4361.2002] [Citation(s) in RCA: 62] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
As is the case with many other protozoan parasites, glycosylphosphatidylinositol (GPI)-anchored proteins dominate the surface of Toxoplasma gondii tachyzoites. The mechanisms by which T. gondii GPI-anchored proteins are synthesized and transported through the unusual triple-membrane structure of the parasite pellicle to the plasma membrane remain largely unknown. As a first step in developing tools to study these processes, we show here that Clostridium septicum alpha-toxin, a pore-forming toxin that targets GPI-anchored protein receptors on the surface of mammalian cells, is active against T. gondii tachyzoites (50% effective concentration, 0.2 nM). Ultrastructural studies reveal that a tight physical connection between the plasma membrane and the underlying membranes of the inner membrane complex is locally disrupted by toxin treatment, resulting in a massive outward extension of the plasma membrane and ultimately lysis of the parasite. Toxin treatment also causes swelling of the parasite endoplasmic reticulum, providing the first direct evidence that alpha-toxin is a vacuolating toxin. Alpha-toxin binds to several parasite GPI-anchored proteins, including surface antigen 3 (SAG3) and SAG1. Interestingly, differences in the toxin-binding profiles between the virulent RH and avirulent P strain were observed. Alpha-toxin may prove to be a powerful experimental tool for molecular genetic analysis of GPI anchor biosynthesis and GPI-anchored protein trafficking in T. gondii and other susceptible protozoa.
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Affiliation(s)
- Michael J Wichroski
- Department of Microbiology and Molecular Genetics, University of Vermont, Burlington 05405, USA
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24
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Azzouz N, Rauscher B, Gerold P, Cesbron-Delauw MF, Dubremetz JF, Schwarz RT. Evidence for de novo sphingolipid biosynthesis in Toxoplasma gondii. Int J Parasitol 2002; 32:677-84. [PMID: 12062486 DOI: 10.1016/s0020-7519(02)00009-7] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Glycolipids are important components of cellular membranes involved in various biological functions. In this report, we describe the identification of the de novo synthesis of glycosphingolipids by Toxoplasma gondii tachyzoites. Parasite-specific glycolipids were identified by metabolic labelling of parasites with tritiated serine and galactose. These glycolipids were characterised as sphingolipids based on the labelling protocol and their insensitivity towards alkaline treatment. Synthesis of parasite glycosphingolipids were inhibited by threo-phenyl-2-palmitoylamino-3-morpholino-1-propanol and L-cycloserine, two well-established inhibitors of de novo sphingolipid biosynthesis. The identified glycolipids were insensitive towards treatment with endoglycoceramidase II indicating that they might belong to globo-type glycosphingolipids. Taken together, we provide evidence for the first time that T. gondii is capable of synthesising glycosphingolipids de novo.
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Affiliation(s)
- Nahid Azzouz
- Medizinisches Zentrum für Hygiene und Medizinische Mikrobiologie, Philipps-Universität Marburg, Robert-Koch Strasse 17, 35037, Marburg, Germany
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