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alpha-Mannosidase: An enzyme that catalyzes the HYDROLYSIS of terminal, non-reducing alpha-D-mannose residues in alpha-D-mannosides. The enzyme plays a role in the processing of newly formed N-glycans and in degradation of mature GLYCOPROTEINS. There are multiple isoforms of alpha-mannosidase, each having its own specific cellular location and pH optimum. Defects in the lysosomal form of the enzyme results in a buildup of mannoside intermediate metabolites and the disease ALPHA-MANNOSIDOSIS.Mannosidases: Glycoside hydrolases that catalyze the hydrolysis of alpha or beta linked MANNOSE.alpha-Mannosidosis: An inborn error of metabolism marked by a defect in the lysosomal isoform of ALPHA-MANNOSIDASE activity that results in lysosomal accumulation of mannose-rich intermediate metabolites. Virtually all patients have psychomotor retardation, facial coarsening, and some degree of dysostosis multiplex. It is thought to be an autosomal recessive disorder.Swainsonine: An indolizidine alkaloid from the plant Swainsona canescens that is a potent alpha-mannosidase inhibitor. Swainsonine also exhibits antimetastatic, antiproliferative, and immunomodulatory activity.DisaccharidasesMannosides: Glycosides formed by the reaction of the hydroxyl group on the anomeric carbon atom of mannose with an alcohol to form an acetal. They include both alpha- and beta-mannosides.Mannose: A hexose or fermentable monosaccharide and isomer of glucose from manna, the ash Fraxinus ornus and related plants. (From Grant & Hackh's Chemical Dictionary, 5th ed & Random House Unabridged Dictionary, 2d ed)Oligosaccharides: Carbohydrates consisting of between two (DISACCHARIDES) and ten MONOSACCHARIDES connected by either an alpha- or beta-glycosidic link. They are found throughout nature in both the free and bound form.Carbohydrate Sequence: The sequence of carbohydrates within POLYSACCHARIDES; GLYCOPROTEINS; and GLYCOLIPIDS.1-Deoxynojirimycin: An alpha-glucosidase inhibitor with antiviral action. Derivatives of deoxynojirimycin may have anti-HIV activity.Carbohydrate Metabolism, Inborn ErrorsLysosomes: A class of morphologically heterogeneous cytoplasmic particles in animal and plant tissues characterized by their content of hydrolytic enzymes and the structure-linked latency of these enzymes. The intracellular functions of lysosomes depend on their lytic potential. The single unit membrane of the lysosome acts as a barrier between the enzymes enclosed in the lysosome and the external substrate. The activity of the enzymes contained in lysosomes is limited or nil unless the vesicle in which they are enclosed is ruptured. Such rupture is supposed to be under metabolic (hormonal) control. (From Rieger et al., Glossary of Genetics: Classical and Molecular, 5th ed)Glycoside HydrolasesPolysaccharidesAcetylglucosaminidase: A beta-N-Acetylhexosaminidase that catalyzes the hydrolysis of terminal, non-reducing 2-acetamido-2-deoxy-beta-glucose residues in chitobiose and higher analogs as well as in glycoproteins. Has been used widely in structural studies on bacterial cell walls and in the study of diseases such as MUCOLIPIDOSIS and various inflammatory disorders of muscle and connective tissue.Carbohydrate Conformation: The characteristic 3-dimensional shape of a carbohydrate.Mannosyl-Glycoprotein Endo-beta-N-Acetylglucosaminidase: A group of related enzymes responsible for the endohydrolysis of the di-N-acetylchitobiosyl unit in high-mannose-content glycopeptides and GLYCOPROTEINS.Aspergillus oryzae: An imperfect fungus present on most agricultural seeds and often responsible for the spoilage of seeds in bulk storage. It is also used in the production of fermented food or drink, especially in Japan.Golgi Apparatus: A stack of flattened vesicles that functions in posttranslational processing and sorting of proteins, receiving them from the rough ENDOPLASMIC RETICULUM and directing them to secretory vesicles, LYSOSOMES, or the CELL MEMBRANE. The movement of proteins takes place by transfer vesicles that bud off from the rough endoplasmic reticulum or Golgi apparatus and fuse with the Golgi, lysosomes or cell membrane. (From Glick, Glossary of Biochemistry and Molecular Biology, 1990)Glycopeptides: Proteins which contain carbohydrate groups attached covalently to the polypeptide chain. The protein moiety is the predominant group with the carbohydrate making up only a small percentage of the total weight.Imino Furanoses: Five-carbon furanose sugars in which the OXYGEN is replaced by a NITROGEN atom.Hexosaminidases: Enzymes that catalyze the hydrolysis of N-acylhexosamine residues in N-acylhexosamides. Hexosaminidases also act on GLUCOSIDES; GALACTOSIDES; and several OLIGOSACCHARIDES.Dictyostelium: A genus of protozoa, formerly also considered a fungus. Its natural habitat is decaying forest leaves, where it feeds on bacteria. D. discoideum is the best-known species and is widely used in biomedical research.Chromosomes, Human, 19-20: The short, metacentric human chromosomes, called group F in the human chromosome classification. This group consists of chromosome pairs 19 and 20.beta-Glucosidase: An exocellulase with specificity for a variety of beta-D-glycoside substrates. It catalyzes the hydrolysis of terminal non-reducing residues in beta-D-glucosides with release of GLUCOSE.Glucosidases: Enzymes that hydrolyze O-glucosyl-compounds. (Enzyme Nomenclature, 1992) EC 3.2.1.-.Cobalt: A trace element that is a component of vitamin B12. It has the atomic symbol Co, atomic number 27, and atomic weight 58.93. It is used in nuclear weapons, alloys, and pigments. Deficiency in animals leads to anemia; its excess in humans can lead to erythrocytosis.Substrate Specificity: A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.Alkaloids: Organic nitrogenous bases. Many alkaloids of medical importance occur in the animal and vegetable kingdoms, and some have been synthesized. (Grant & Hackh's Chemical Dictionary, 5th ed)Glycosylation: The chemical or biochemical addition of carbohydrate or glycosyl groups to other chemicals, especially peptides or proteins. Glycosyl transferases are used in this biochemical reaction.alpha-L-Fucosidase: An enzyme that catalyzes the hydrolysis of an alpha L-fucoside to yield an alcohol and L-fucose. Deficiency of this enzyme can cause FUCOSIDOSIS. EC 3.2.1.51.Molecular Sequence Data: Descriptions of specific amino acid, carbohydrate, or nucleotide sequences which have appeared in the published literature and/or are deposited in and maintained by databanks such as GENBANK, European Molecular Biology Laboratory (EMBL), National Biomedical Research Foundation (NBRF), or other sequence repositories.Mannans: Polysaccharides consisting of mannose units.Glycoproteins: Conjugated protein-carbohydrate compounds including mucins, mucoid, and amyloid glycoproteins.Erythrina: A genus of leguminous shrubs or trees, mainly tropical, yielding useful compounds such as ALKALOIDS and PLANT LECTINS.GlucosamineKinetics: The rate dynamics in chemical or physical systems.Carbohydrates: The largest class of organic compounds, including STARCH; GLYCOGEN; CELLULOSE; POLYSACCHARIDES; and simple MONOSACCHARIDES. Carbohydrates are composed of carbon, hydrogen, and oxygen in a ratio of Cn(H2O)n.alpha-Glucosidases: Enzymes that catalyze the exohydrolysis of 1,4-alpha-glucosidic linkages with release of alpha-glucose. Deficiency of alpha-1,4-glucosidase may cause GLYCOGEN STORAGE DISEASE TYPE II.Plant Poisoning: Poisoning by the ingestion of plants or its leaves, berries, roots or stalks. The manifestations in both humans and animals vary in severity from mild to life threatening. In animals, especially domestic animals, it is usually the result of ingesting moldy or fermented forage.Endoplasmic Reticulum: A system of cisternae in the CYTOPLASM of many cells. In places the endoplasmic reticulum is continuous with the plasma membrane (CELL MEMBRANE) or outer membrane of the nuclear envelope. If the outer surfaces of the endoplasmic reticulum membranes are coated with ribosomes, the endoplasmic reticulum is said to be rough-surfaced (ENDOPLASMIC RETICULUM, ROUGH); otherwise it is said to be smooth-surfaced (ENDOPLASMIC RETICULUM, SMOOTH). (King & Stansfield, A Dictionary of Genetics, 4th ed)Molecular Weight: The sum of the weight of all the atoms in a molecule.Ginkgo biloba: The only specie of the genus Ginkgo, family Ginkgoacea. It is the source of extracts of medicinal interest, especially Egb 761. Ginkgo may refer to the genus or species.Methylmannosides: Mannosides formed by the reaction of the hydroxyl group on the anomeric carbon atom of mannose with methyl alcohol. They include both alpha- and beta-methylmannosides.Pichia: Yeast-like ascomycetous fungi of the family Saccharomycetaceae, order SACCHAROMYCETALES isolated from exuded tree sap.Mannosephosphates: Phosphoric acid esters of mannose.Gram-Positive Rods: A large group of rod-shaped bacteria that retains the crystal violet stain when treated by Gram's method.Hydrolases: Any member of the class of enzymes that catalyze the cleavage of the substrate and the addition of water to the resulting molecules, e.g., ESTERASES, glycosidases (GLYCOSIDE HYDROLASES), lipases, NUCLEOTIDASES, peptidases (PEPTIDE HYDROLASES), and phosphatases (PHOSPHORIC MONOESTER HYDROLASES). EC 3.Oviducts: Ducts that serve exclusively for the passage of eggs from the ovaries to the exterior of the body. In non-mammals, they are termed oviducts. In mammals, they are highly specialized and known as FALLOPIAN TUBES.