Biomaterial Database

Toxoplasma gondii: secretion of a potent nucleoside triphosphate hydrolase into the parasitophorous vacuole. 1994

L D Sibley, and I R Niesman, and T Asai, and T Takeuchi

Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri 63110.

Toxoplasma gondii is an obligate intracellular parasite capable of invading a wide range of host cells where it residues in a specially modified compartment termed the parasitophorous vacuole. This compartment provides a protected environment for the parasite which enters a rapid growth phase shortly after invasion. To identify functional components of this interface, we have used immunolabeling and cell fractionation to localize the potent nucleoside triphosphate hydrolase (NTPase) produced by Toxoplasma. In extracellular tachyzoites, NTPase was not exposed on the cell surface but was localized in small vesicles, called dense granules, scattered throughout the cell cytoplasm. Shortly following invasion. NTPase was secreted from dense granules and occupied the lumen of the parasitophorous vacuole where it was often associated with the intravacuolar network. NTPase was exclusively found in the supernatant in cell fractionation studies of both extracellular tachyzoites lysed by freeze-thaw and following secretion into the parasitophorous vacuole. These studies provide evidence for the rapid secretion of NTPase into the parasitophorous vacuole, where it may play a key role in processing of nucleotides for purine salvage by the parasite.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D002458	Cell Fractionation	Techniques to partition various components of the cell into SUBCELLULAR FRACTIONS.	Cell Fractionations,Fractionation, Cell,Fractionations, Cell
D004591	Electrophoresis, Polyacrylamide Gel	Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.	Polyacrylamide Gel Electrophoresis,SDS-PAGE,Sodium Dodecyl Sulfate-PAGE,Gel Electrophoresis, Polyacrylamide,SDS PAGE,Sodium Dodecyl Sulfate PAGE,Sodium Dodecyl Sulfate-PAGEs
D005455	Fluorescent Antibody Technique	Test for tissue antigen using either a direct method, by conjugation of antibody with fluorescent dye (FLUORESCENT ANTIBODY TECHNIQUE, DIRECT) or an indirect method, by formation of antigen-antibody complex which is then labeled with fluorescein-conjugated anti-immunoglobulin antibody (FLUORESCENT ANTIBODY TECHNIQUE, INDIRECT). The tissue is then examined by fluorescence microscopy.	Antinuclear Antibody Test, Fluorescent,Coon's Technique,Fluorescent Antinuclear Antibody Test,Fluorescent Protein Tracing,Immunofluorescence Technique,Coon's Technic,Fluorescent Antibody Technic,Immunofluorescence,Immunofluorescence Technic,Antibody Technic, Fluorescent,Antibody Technics, Fluorescent,Antibody Technique, Fluorescent,Antibody Techniques, Fluorescent,Coon Technic,Coon Technique,Coons Technic,Coons Technique,Fluorescent Antibody Technics,Fluorescent Antibody Techniques,Fluorescent Protein Tracings,Immunofluorescence Technics,Immunofluorescence Techniques,Protein Tracing, Fluorescent,Protein Tracings, Fluorescent,Technic, Coon's,Technic, Fluorescent Antibody,Technic, Immunofluorescence,Technics, Fluorescent Antibody,Technics, Immunofluorescence,Technique, Coon's,Technique, Fluorescent Antibody,Technique, Immunofluorescence,Techniques, Fluorescent Antibody,Techniques, Immunofluorescence,Tracing, Fluorescent Protein,Tracings, Fluorescent Protein
D000818	Animals	Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, Animalia was one of the kingdoms. Under the modern three domain model, Animalia represents one of the many groups in the domain EUKARYOTA.	Animal,Metazoa,Animalia
D014122	Toxoplasma	A genus of protozoa parasitic to birds and mammals. T. gondii is one of the most common infectious pathogenic animal parasites of man.	Toxoplasma gondii,Toxoplasma gondius,Toxoplasmas,gondius, Toxoplasma
D015153	Blotting, Western	Identification of proteins or peptides that have been electrophoretically separated by blot transferring from the electrophoresis gel to strips of nitrocellulose paper, followed by labeling with antibody probes.	Immunoblotting, Western,Western Blotting,Western Immunoblotting,Blot, Western,Immunoblot, Western,Western Blot,Western Immunoblot,Blots, Western,Blottings, Western,Immunoblots, Western,Immunoblottings, Western,Western Blots,Western Blottings,Western Immunoblots,Western Immunoblottings
D016253	Microscopy, Immunoelectron	Microscopy in which the samples are first stained immunocytochemically and then examined using an electron microscope. Immunoelectron microscopy is used extensively in diagnostic virology as part of very sensitive immunoassays.	Immunoelectron Microscopy,Microscopy, Immuno-Electron,Immuno-Electron Microscopies,Immuno-Electron Microscopy,Immunoelectron Microscopies,Microscopies, Immuno-Electron,Microscopies, Immunoelectron,Microscopy, Immuno Electron
D017766	Acid Anhydride Hydrolases	A group of enzymes that catalyze the hydrolysis of diphosphate bonds in compounds such as nucleoside di- and tri-phosphates, and sulfonyl-containing anhydrides such as adenylylsulfate. (Enzyme Nomenclature, 1992) EC 3.6.	Anhydride Hydrolases, Acid,Hydrolases, Acid Anhydride
D043583	Nucleoside-Triphosphatase	An enzyme which catalyzes the hydrolysis of nucleoside triphosphates to nucleoside diphosphates. It may also catalyze the hydrolysis of nucleotide triphosphates, diphosphates, thiamine diphosphates and FAD. The nucleoside triphosphate phosphohydrolases I and II are subtypes of the enzyme which are found mostly in viruses.	NTPase,Nucleoside Triphosphatase,Nucleoside Triphosphate Phosphohydrolase,Nucleoside Triphosphate Phosphohydrolase I,Nucleoside Triphosphate Phosphohydrolase II,Nucleosidetriphosphatase,Phosphohydrolase, Nucleoside Triphosphate,Triphosphatase, Nucleoside,Triphosphate Phosphohydrolase, Nucleoside