Glycosphingolipids
Lipids containing at least one monosaccharide residue and either a sphingoid or a ceramide (CERAMIDES). They are subdivided into NEUTRAL GLYCOSPHINGOLIPIDS comprising monoglycosyl- and oligoglycosylsphingoids and monoglycosyl- and oligoglycosylceramides; and ACIDIC GLYCOSPHINGOLIPIDS which comprises sialosylglycosylsphingolipids (GANGLIOSIDES); SULFOGLYCOSPHINGOLIPIDS (formerly known as sulfatides), glycuronoglycosphingolipids, and phospho- and phosphonoglycosphingolipids. (From IUPAC's webpage)
Neutral Glycosphingolipids
Acidic Glycosphingolipids
A subclass of GLYCOSPHINGOLIPIDS containing large polar heads made up of several sugar units. One or more of their terminal sugar units are bound to a negatively charged molecule at pH 7. Members of this class include: GANGLIOSIDES, uronoglycosphingolipids, SULFOGLYCOSPHINGOLIPIDS, phosphoglycosphingolipids, and phosphonoglycosphingolipids.
Chromatography, Thin Layer
Lactosylceramides
Gangliosides
A subclass of ACIDIC GLYCOSPHINGOLIPIDS. They contain one or more sialic acid (N-ACETYLNEURAMINIC ACID) residues. Using the Svennerholm system of abbrevations, gangliosides are designated G for ganglioside, plus subscript M, D, or T for mono-, di-, or trisialo, respectively, the subscript letter being followed by a subscript arabic numeral to indicated sequence of migration in thin-layer chromatograms. (From Oxford Dictionary of Biochemistry and Molecular Biology, 1997)
Globosides
Glycosphingolipids containing N-acetylglucosamine (paragloboside) or N-acetylgalactosamine (globoside). Globoside is the P antigen on erythrocytes and paragloboside is an intermediate in the biosynthesis of erythrocyte blood group ABH and P 1 glycosphingolipid antigens. The accumulation of globoside in tissue, due to a defect in hexosaminidases A and B, is the cause of Sandhoff disease.
Carbohydrate Sequence
Glucosylceramides
Cerebrosides which contain as their polar head group a glucose moiety bound in glycosidic linkage to the hydroxyl group of ceramides. Their accumulation in tissue, due to a defect in beta-glucosidase, is the cause of Gaucher's disease.
Sulfoglycosphingolipids
Cerebrosides
Neutral glycosphingolipids that contain a monosaccharide, normally glucose or galactose, in 1-ortho-beta-glycosidic linkage with the primary alcohol of an N-acyl sphingoid (ceramide). In plants the monosaccharide is normally glucose and the sphingoid usually phytosphingosine. In animals, the monosaccharide is usually galactose, though this may vary with the tissue and the sphingoid is usually sphingosine or dihydrosphingosine. (From Oxford Dictionary of Biochemistry and Molecular Biology, 1st ed)
Glycolipids
Any compound containing one or more monosaccharide residues bound by a glycosidic linkage to a hydrophobic moiety such as an acylglycerol (see GLYCERIDES), a sphingoid, a ceramide (CERAMIDES) (N-acylsphingoid) or a prenyl phosphate. (From IUPAC's webpage)
G(M3) Ganglioside
A ganglioside present in abnormally large amounts in the brain and liver due to a deficient biosynthetic enzyme, G(M3):UDP-N-acetylgalactosaminyltransferase. Deficiency of this enzyme prevents the formation of G(M2) ganglioside from G(M3) ganglioside and is the cause of an anabolic sphingolipidosis.
Ceramides
Members of the class of neutral glycosphingolipids. They are the basic units of SPHINGOLIPIDS. They are sphingoids attached via their amino groups to a long chain fatty acyl group. They abnormally accumulate in FABRY DISEASE.
Sphingolipids
A class of membrane lipids that have a polar head and two nonpolar tails. They are composed of one molecule of the long-chain amino alcohol sphingosine (4-sphingenine) or one of its derivatives, one molecule of a long-chain acid, a polar head alcohol and sometimes phosphoric acid in diester linkage at the polar head group. (Lehninger et al, Principles of Biochemistry, 2nd ed)
G(M1) Ganglioside
Trihexosylceramides
Glycosphingolipids which contain as their polar head group a trisaccharide (galactose-galactose-glucose) moiety bound in glycosidic linkage to the hydroxyl group of ceramide. Their accumulation in tissue, due to a defect in ceramide trihexosidase, is the cause of angiokeratoma corporis diffusum (FABRY DISEASE).
Psychosine
An intermediate in the biosynthesis of cerebrosides. It is formed by reaction of sphingosine with UDP-galactose and then itself reacts with fatty acid-Coenzyme A to form the cerebroside.
Forssman Antigen
Spectrometry, Mass, Fast Atom Bombardment
A mass spectrometric technique that is used for the analysis of a wide range of biomolecules, such as glycoalkaloids, glycoproteins, polysaccharides, and peptides. Positive and negative fast atom bombardment spectra are recorded on a mass spectrometer fitted with an atom gun with xenon as the customary beam. The mass spectra obtained contain molecular weight recognition as well as sequence information.
G(M2) Ganglioside
A glycosphingolipid that accumulates due to a deficiency of hexosaminidase A or B (BETA-N-ACETYLHEXOSAMINIDASES), or GM2 activator proteinM2 resulting in GANGLIOSIDOSES, heredity metabolic disorders that include TAY-SACHS DISEASE and SANDHOFF DISEASE.
ABO Blood-Group System
The major human blood type system which depends on the presence or absence of two antigens A and B. Type O occurs when neither A nor B is present and AB when both are present. A and B are genetic factors that determine the presence of enzymes for the synthesis of certain glycoproteins mainly in the red cell membrane.
Mass Spectrometry
Sphingolipid Activator Proteins
A family of glycoprotein cofactors that are required for the efficient catabolization of SPHINGOLIPIDS by specific acid hydrolases such as GLUCOSYLCERAMIDASE; GALACTOCEREBROSIDASE; BETA-N-ACETYLHEXOSAMINIDASE; and CEREBROSIDE-SULFATASE.
Glucosyltransferases
Chromatography, Gas
Fractionation of a vaporized sample as a consequence of partition between a mobile gaseous phase and a stationary phase held in a column. Two types are gas-solid chromatography, where the fixed phase is a solid, and gas-liquid, in which the stationary phase is a nonvolatile liquid supported on an inert solid matrix.
Antigens, Heterophile
Fabry Disease
An X-linked inherited metabolic disease caused by a deficiency of lysosomal ALPHA-GALACTOSIDASE A. It is characterized by intralysosomal accumulation of globotriaosylceramide and other GLYCOSPHINGOLIPIDS in blood vessels throughout the body leading to multi-system complications including renal, cardiac, cerebrovascular, and skin disorders.
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.
Saposins
A group of four homologous sphingolipid activator proteins that are formed from proteolytic cleavage of a common protein precursor molecule referred to as prosaposin.
Glycoside Hydrolases
Glycoside Hydrolases are a class of enzymes that catalyze the hydrolysis of glycosidic bonds, resulting in the breakdown of complex carbohydrates and oligosaccharides into simpler sugars.
Galactosylceramides
Cerebrosides which contain as their polar head group a galactose moiety bound in glycosidic linkage to the hydroxyl group of ceramide. Their accumulation in tissue, due to a defect in beta-galactosidase, is the cause of galactosylceramide lipidosis or globoid cell leukodystrophy.
Blood Group Antigens
Sets of cell surface antigens located on BLOOD CELLS. They are usually membrane GLYCOPROTEINS or GLYCOLIPIDS that are antigenically distinguished by their carbohydrate moieties.
Membrane Microdomains
Detergent-insoluble CELL MEMBRANE components. They are enriched in SPHINGOLIPIDS and CHOLESTEROL and clustered with glycosyl-phosphatidylinositol (GPI)-anchored proteins.
Ascaris suum
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.
alpha-Galactosidase
An enzyme that catalyzes the hydrolysis of terminal, non-reducing alpha-D-galactose residues in alpha-galactosides including galactose oligosaccharides, galactomannans, and galactolipids.
G(M2) Activator Protein
Galactose
An aldohexose that occurs naturally in the D-form in lactose, cerebrosides, gangliosides, and mucoproteins. Deficiency of galactosyl-1-phosphate uridyltransferase (GALACTOSE-1-PHOSPHATE URIDYL-TRANSFERASE DEFICIENCY DISEASE) causes an error in galactose metabolism called GALACTOSEMIA, resulting in elevations of galactose in the blood.
1-Deoxynojirimycin
Chromatography, High Pressure Liquid
Sphingolipidoses
A group of inherited metabolic disorders characterized by the intralysosomal accumulation of SPHINGOLIPIDS primarily in the CENTRAL NERVOUS SYSTEM and to a variable degree in the visceral organs. They are classified by the enzyme defect in the degradation pathway and the substrate accumulation (or storage). Clinical features vary in subtypes but neurodegeneration is a common sign.
Imino Sugars
Sugars in which the OXYGEN is replaced by a NITROGEN atom. This substitution prevents normal METABOLISM resulting in inhibition of GLYCOSIDASES and GLYCOSYLTRANSFERASES.
Fatty Acids
Organic, monobasic acids derived from hydrocarbons by the equivalent of oxidation of a methyl group to an alcohol, aldehyde, and then acid. Fatty acids are saturated and unsaturated (FATTY ACIDS, UNSATURATED). (Grant & Hackh's Chemical Dictionary, 5th ed)
Neuraminic Acids
Neuraminic acids are a family of nine-carbon sugars (sialic acids) that are commonly found as terminal residues on glycoproteins and gangliosides in animal tissues, playing crucial roles in various biological processes including cell recognition, inflammation, and bacterial/viral infectivity.
Oligosaccharides
Sialyltransferases
A group of enzymes with the general formula CMP-N-acetylneuraminate:acceptor N-acetylneuraminyl transferase. They catalyze the transfer of N-acetylneuraminic acid from CMP-N-acetylneuraminic acid to an acceptor, which is usually the terminal sugar residue of an oligosaccharide, a glycoprotein, or a glycolipid. EC 2.4.99.-.
Stage-Specific Embryonic Antigens
Hexoses
Hexoses are simple monosaccharides, specifically six-carbon sugars, which include glucose, fructose, and galactose, and play crucial roles in biological processes such as energy production and storage, and structural components of cells.
Sphingomyelins
A class of sphingolipids found largely in the brain and other nervous tissue. They contain phosphocholine or phosphoethanolamine as their polar head group so therefore are the only sphingolipids classified as PHOSPHOLIPIDS.
Magnetic Resonance Spectroscopy
Brain Chemistry
Galactosyltransferases
N-Acetylgalactosaminyltransferases
P Blood-Group System
Sphingosine
An amino alcohol with a long unsaturated hydrocarbon chain. Sphingosine and its derivative sphinganine are the major bases of the sphingolipids in mammals. (Dorland, 28th ed)
Sialic Acids
Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
A mass spectrometric technique that is used for the analysis of large biomolecules. Analyte molecules are embedded in an excess matrix of small organic molecules that show a high resonant absorption at the laser wavelength used. The matrix absorbs the laser energy, thus inducing a soft disintegration of the sample-matrix mixture into free (gas phase) matrix and analyte molecules and molecular ions. In general, only molecular ions of the analyte molecules are produced, and almost no fragmentation occurs. This makes the method well suited for molecular weight determinations and mixture analysis.
Sandhoff Disease
An autosomal recessive neurodegenerative disorder characterized by an accumulation of G(M2) GANGLIOSIDE in neurons and other tissues. It is caused by mutation in the common beta subunit of HEXOSAMINIDASE A and HEXOSAMINIDASE B. Thus this disease is also known as the O variant since both hexosaminidase A and B are missing. Clinically, it is indistinguishable from TAY-SACHS DISEASE.
Gaucher Disease
An autosomal recessive disorder caused by a deficiency of acid beta-glucosidase (GLUCOSYLCERAMIDASE) leading to intralysosomal accumulation of glycosylceramide mainly in cells of the MONONUCLEAR PHAGOCYTE SYSTEM. The characteristic Gaucher cells, glycosphingolipid-filled HISTIOCYTES, displace normal cells in BONE MARROW and visceral organs causing skeletal deterioration, hepatosplenomegaly, and organ dysfunction. There are several subtypes based on the presence and severity of neurological involvement.
Diptera
An order of the class Insecta. Wings, when present, number two and distinguish Diptera from other so-called flies, while the halteres, or reduced hindwings, separate Diptera from other insects with one pair of wings. The order includes the families Calliphoridae, Oestridae, Phoridae, SARCOPHAGIDAE, Scatophagidae, Sciaridae, SIMULIIDAE, Tabanidae, Therevidae, Trypetidae, CERATOPOGONIDAE; CHIRONOMIDAE; CULICIDAE; DROSOPHILIDAE; GLOSSINIDAE; MUSCIDAE; TEPHRITIDAE; and PSYCHODIDAE. The larval form of Diptera species are called maggots (see LARVA).
Glycoconjugates
Carbohydrates covalently linked to a nonsugar moiety (lipids or proteins). The major glycoconjugates are glycoproteins, glycopeptides, peptidoglycans, glycolipids, and lipopolysaccharides. (From Biochemical Nomenclature and Related Documents, 2d ed; From Principles of Biochemistry, 2d ed)
Glycosyltransferases
Enzymes that catalyze the transfer of glycosyl groups to an acceptor. Most often another carbohydrate molecule acts as an acceptor, but inorganic phosphate can also act as an acceptor, such as in the case of PHOSPHORYLASES. Some of the enzymes in this group also catalyze hydrolysis, which can be regarded as transfer of a glycosyl group from the donor to water. Subclasses include the HEXOSYLTRANSFERASES; PENTOSYLTRANSFERASES; SIALYLTRANSFERASES; and those transferring other glycosyl groups. EC 2.4.
Leukodystrophy, Globoid Cell
An autosomal recessive metabolic disorder caused by a deficiency of GALACTOSYLCERAMIDASE leading to intralysosomal accumulation of galactolipids such as GALACTOSYLCERAMIDES and PSYCHOSINE. It is characterized by demyelination associated with large multinucleated globoid cells, predominantly involving the white matter of the central nervous system. The loss of MYELIN disrupts normal conduction of nerve impulses.
Meconium
The thick green-to-black mucilaginous material found in the intestines of a full-term fetus. It consists of secretions of the INTESTINAL GLANDS; BILE PIGMENTS; FATTY ACIDS; AMNIOTIC FLUID; and intrauterine debris. It constitutes the first stools passed by a newborn.
Cell Membrane
Erythrocytes
Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.
Niemann-Pick Diseases
A group of autosomal recessive disorders in which harmful quantities of lipids accumulate in the viscera and the central nervous system. They can be caused by deficiencies of enzyme activities (SPHINGOMYELIN PHOSPHODIESTERASE) or defects in intracellular transport, resulting in the accumulation of SPHINGOMYELINS and CHOLESTEROL. There are various subtypes based on their clinical and genetic differences.
alpha-N-Acetylgalactosaminidase
Lysosomal Storage Diseases
Caveolae
Endocytic/exocytic CELL MEMBRANE STRUCTURES rich in glycosphingolipids, cholesterol, and lipid-anchored membrane proteins that function in ENDOCYTOSIS (potocytosis), transcytosis, and SIGNAL TRANSDUCTION. Caveolae assume various shapes from open pits to closed vesicles. Caveolar coats are composed of CAVEOLINS.
Spectrometry, Mass, Electrospray Ionization
A mass spectrometry technique used for analysis of nonvolatile compounds such as proteins and macromolecules. The technique involves preparing electrically charged droplets from analyte molecules dissolved in solvent. The electrically charged droplets enter a vacuum chamber where the solvent is evaporated. Evaporation of solvent reduces the droplet size, thereby increasing the coulombic repulsion within the droplet. As the charged droplets get smaller, the excess charge within them causes them to disintegrate and release analyte molecules. The volatilized analyte molecules are then analyzed by mass spectrometry.
Angiokeratoma
Chemistry
Gas Chromatography-Mass Spectrometry
A microanalytical technique combining mass spectrometry and gas chromatography for the qualitative as well as quantitative determinations of compounds.
Methylation
Addition of methyl groups. In histo-chemistry methylation is used to esterify carboxyl groups and remove sulfate groups by treating tissue sections with hot methanol in the presence of hydrochloric acid. (From Stedman, 25th ed)
Chemical Phenomena
Lipidoses
Gangliosidoses, GM2
A group of recessively inherited diseases characterized by the intralysosomal accumulation of G(M2) GANGLIOSIDE in the neuronal cells. Subtypes include mutations of enzymes in the BETA-N-ACETYLHEXOSAMINIDASES system or G(M2) ACTIVATOR PROTEIN leading to disruption of normal degradation of GANGLIOSIDES, a subclass of ACIDIC GLYCOSPHINGOLIPIDS.