Sialic Acids: A group of naturally occurring N-and O-acyl derivatives of the deoxyamino sugar neuraminic acid. They are ubiquitously distributed in many tissues.N-Acetylneuraminic Acid: An N-acyl derivative of neuraminic acid. N-acetylneuraminic acid occurs in many polysaccharides, glycoproteins, and glycolipids in animals and bacteria. (From Dorland, 28th ed, p1518)Neuraminidase: An enzyme that catalyzes the hydrolysis of alpha-2,3, alpha-2,6-, and alpha-2,8-glycosidic linkages (at a decreasing rate, respectively) of terminal sialic residues in oligosaccharides, glycoproteins, glycolipids, colominic acid, and synthetic substrate. (From Enzyme Nomenclature, 1992)Neuraminic AcidsSialic Acid Storage Disease: Autosomal recessive neurodegenerative disorders caused by lysosomal membrane transport defects that result in accumulation of free sialic acid (N-ACETYLNEURAMINIC ACID) within the lysosomes. The two main clinical phenotypes, which are allelic variants of the SLC17A5 gene, are ISSD, a severe infantile form, or Salla disease, a slowly progressive adult form, named for the geographic area in Finland where the kindred first studied resided.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.-.Sialic Acid Binding Immunoglobulin-like Lectins: A family of SIALIC ACID binding proteins found in vertebrate species. They are transmembrane proteins which act as cell surface receptors for a variety of sialylated GLYCOCONJUGATES. While a subset of siglec protein subtypes are evolutionarily conserved between mammalian species, there are many others that are species specific.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)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)Lectins: Proteins that share the common characteristic of binding to carbohydrates. Some ANTIBODIES and carbohydrate-metabolizing proteins (ENZYMES) also bind to carbohydrates, however they are not considered lectins. PLANT LECTINS are carbohydrate-binding proteins that have been primarily identified by their hemagglutinating activity (HEMAGGLUTININS). However, a variety of lectins occur in animal species where they serve diverse array of functions through specific carbohydrate recognition.Sialic Acid Binding Ig-like Lectin 1: A sialic acid binding lectin that was originally identified as an adhesion molecule for inflammatory MACROPHAGES and activated MONOCYTES. This protein is the largest known siglec subtype and contains 16 immunoglobulin C2-set domains. It plays a role in cell to cell interactions and interactions with BACTERIA.Acetylesterase: An enzyme that catalyzes the conversion of acetate esters and water to alcohols and acetate. EC Monophosphate N-Acetylneuraminic Acid: A nucleoside monophosphate sugar which donates N-acetylneuraminic acid to the terminal sugar of a ganglioside or glycoprotein.Carbohydrate Sequence: The sequence of carbohydrates within POLYSACCHARIDES; GLYCOPROTEINS; and GLYCOLIPIDS.Sialic Acid Binding Ig-like Lectin 2: A lectin and cell adhesion molecule found in B-LYMPHOCYTES. It interacts with SIALIC ACIDS and mediates signaling from B-CELL ANTIGEN RECEPTORS.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.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.PolysaccharidesCarbohydrate Conformation: The characteristic 3-dimensional shape of a carbohydrate.Periodic Acid: A strong oxidizing agent.Glycoproteins: Conjugated protein-carbohydrate compounds including mucins, mucoid, and amyloid glycoproteins.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.Receptors, Virus: Specific molecular components of the cell capable of recognizing and interacting with a virus, and which, after binding it, are capable of generating some signal that initiates the chain of events leading to the biological response.N-Acylneuraminate Cytidylyltransferase: An enzyme that forms CMP-acylneuraminic acids, which donate the N-acylneuraminic acid residues to the terminal sugar residue of a ganglioside or glycoprotein. EC 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.Sialoglycoproteins: Glycoproteins which contain sialic acid as one of their carbohydrates. They are often found on or in the cell or tissue membranes and participate in a variety of biological activities.Oxo-Acid-Lyases: Enzymes that catalyze the cleavage of a carbon-carbon bond of a 3-hydroxy acid. (Dorland, 28th ed) EC 4.1.3.Mucins: High molecular weight mucoproteins that protect the surface of EPITHELIAL CELLS by providing a barrier to particulate matter and microorganisms. Membrane-anchored mucins may have additional roles concerned with protein interactions at the cell surface.Maackia: A plant genus of the family FABACEAE. It contains a hemagglutinin.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.Amino Sugars: SUGARS containing an amino group. GLYCOSYLATION of other compounds with these amino sugars results in AMINOGLYCOSIDES.FucoseCarbohydrate Epimerases: Enzymes that catalyze the epimerization of chiral centers within carbohydrates or their derivatives. EC 5.1.3.Chromatography, Thin Layer: Chromatography on thin layers of adsorbents rather than in columns. The adsorbent can be alumina, silica gel, silicates, charcoals, or cellulose. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Wheat Germ Agglutinins: Lectins purified from the germinating seeds of common wheat (Triticum vulgare); these bind to certain carbohydrate moieties on cell surface glycoproteins and are used to identify certain cell populations and inhibit or promote some immunological or physiological activities. There are at least two isoforms of this lectin.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.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.Carbohydrate Metabolism, Inborn ErrorsPlant Lectins: Protein or glycoprotein substances of plant origin that bind to sugar moieties in cell walls or membranes. Some carbohydrate-metabolizing proteins (ENZYMES) from PLANTS also bind to carbohydrates, however they are not considered lectins. Many plant lectins change the physiology of the membrane of BLOOD CELLS to cause agglutination, mitosis, or other biochemical changes. They may play a role in plant defense mechanisms.Hemagglutination: The aggregation of ERYTHROCYTES by AGGLUTININS, including antibodies, lectins, and viral proteins (HEMAGGLUTINATION, VIRAL).Glycophorin: The major sialoglycoprotein of the human erythrocyte membrane. It consists of at least two sialoglycopeptides and is composed of 60% carbohydrate including sialic acid and 40% protein. It is involved in a number of different biological activities including the binding of MN blood groups, influenza viruses, kidney bean phytohemagglutinin, and wheat germ agglutinin.Virus Attachment: The binding of virus particles to receptors on the host cell surface. For enveloped viruses, the virion ligand is usually a surface glycoprotein as is the cellular receptor. For non-enveloped viruses, the virus CAPSID serves as the ligand.Sugar AcidsGlycocalyx: The carbohydrate-rich zone on the cell surface. This zone can be visualized by a variety of stains as well as by its affinity for lectins. Although most of the carbohydrate is attached to intrinsic plasma membrane molecules, the glycocalyx usually also contains both glycoproteins and proteoglycans that have been secreted into the extracellular space and then adsorbed onto the cell surface. (Alberts et al., Molecular Biology of the Cell, 3d ed, p502)Erythrocytes: Red blood cells. Mature erythrocytes are non-nucleated, biconcave disks containing HEMOGLOBIN whose function is to transport OXYGEN.Glycoside HydrolasesCell Membrane: The lipid- and protein-containing, selectively permeable membrane that surrounds the cytoplasm in prokaryotic and eukaryotic cells.Ribosome Inactivating Proteins: N-Glycosidases that remove adenines from RIBOSOMAL RNA, depurinating the conserved alpha-sarcin loop of 28S RIBOSOMAL RNA. They often consist of a toxic A subunit and a binding lectin B subunit. They may be considered as PROTEIN SYNTHESIS INHIBITORS. They are found in many PLANTS and have cytotoxic and antiviral activity.GlucosamineAcetylation: Formation of an acetyl derivative. (Stedman, 25th ed)Acetylgalactosamine: The N-acetyl derivative of galactosamine.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)OrosomucoidChromatography, High Pressure Liquid: Liquid chromatographic techniques which feature high inlet pressures, high sensitivity, and high speed.Cell Line: Established cell cultures that have the potential to propagate indefinitely.Asialoglycoproteins: Endogenous glycoproteins from which SIALIC ACID has been removed by the action of sialidases. They bind tightly to the ASIALOGLYCOPROTEIN RECEPTOR which is located on hepatocyte plasma membranes. After internalization by adsorptive ENDOCYTOSIS they are delivered to LYSOSOMES for degradation. Therefore receptor-mediated clearance of asialoglycoproteins is an important aspect of the turnover of plasma glycoproteins. They are elevated in serum of patients with HEPATIC CIRRHOSIS or HEPATITIS.G(M1) Ganglioside: A specific monosialoganglioside that accumulates abnormally within the nervous system due to a deficiency of GM1-b-galactosidase, resulting in GM1 gangliosidosis.3-Deazauridine: 4-Hydroxy-1-(beta-D-ribofuranosyl)-2-pyridinone. Analog of uridine lacking a ring-nitrogen in the 3-position. Functions as an antineoplastic agent.Hemagglutinin Glycoproteins, Influenza Virus: Membrane glycoproteins from influenza viruses which are involved in hemagglutination, virus attachment, and envelope fusion. Fourteen distinct subtypes of HA glycoproteins and nine of NA glycoproteins have been identified from INFLUENZA A VIRUS; no subtypes have been identified for Influenza B or Influenza C viruses.Electrophoresis, Polyacrylamide Gel: Electrophoresis in which a polyacrylamide gel is used as the diffusion medium.Cricetinae: A subfamily in the family MURIDAE, comprising the hamsters. Four of the more common genera are Cricetus, CRICETULUS; MESOCRICETUS; and PHODOPUS.HexosesOrganic Anion Transporters: Proteins involved in the transport of organic anions. They play an important role in the elimination of a variety of endogenous substances, xenobiotics and their metabolites from the body.Lysosomal Storage Diseases: Inborn errors of metabolism characterized by defects in specific lysosomal hydrolases and resulting in intracellular accumulation of unmetabolized substrates.Molecular Weight: The sum of the weight of all the atoms in a molecule.Submandibular Gland: One of two salivary glands in the neck, located in the space bound by the two bellies of the digastric muscle and the angle of the mandible. It discharges through the submandibular duct. The secretory units are predominantly serous although a few mucous alveoli, some with serous demilunes, occur. (Stedman, 25th ed)Streptococcus agalactiae: A bacterium which causes mastitis in cattle and occasionally in man.Influenzavirus C: A genus of the family ORTHOMYXOVIRIDAE comprising viruses similar to types A and B but less common, more stable, more homogeneous, and lacking the neuraminidase protein. They have not been associated with epidemics but may cause mild influenza. Influenza C virus is the type species.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)Chromatography, Ion Exchange: Separation technique in which the stationary phase consists of ion exchange resins. The resins contain loosely held small ions that easily exchange places with other small ions of like charge present in solutions washed over the resins.Peanut Agglutinin: Lectin purified from peanuts (ARACHIS HYPOGAEA). It binds to poorly differentiated cells and terminally differentiated cells and is used in cell separation techniques.CHO Cells: CELL LINE derived from the ovary of the Chinese hamster, Cricetulus griseus (CRICETULUS). The species is a favorite for cytogenetic studies because of its small chromosome number. The cell line has provided model systems for the study of genetic alterations in cultured mammalian cells.Chromatography, Affinity: A chromatographic technique that utilizes the ability of biological molecules to bind to certain ligands specifically and reversibly. It is used in protein biochemistry. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)Sialic Acid Binding Ig-like Lectin 3: A 67-kDa sialic acid binding lectin that is specific for MYELOID CELLS and MONOCYTE-MACROPHAGE PRECURSOR CELLS. This protein is the smallest siglec subtype and contains a single immunoglobulin C2-set domain. It may play a role in intracellular signaling via its interaction with SHP-1 PROTEIN-TYROSINE PHOSPHATASE and SHP-2 PROTEIN-TYROSINE PHOSPHATASE.Monosaccharides: Simple sugars, carbohydrates which cannot be decomposed by hydrolysis. They are colorless crystalline substances with a sweet taste and have the same general formula CnH2nOn. (From Dorland, 28th ed)Cytidine Monophosphate: Cytidine (dihydrogen phosphate). A cytosine nucleotide containing one phosphate group esterified to the sugar moiety in the 2', 3' or 5' position.Microbiological Phenomena: Physiological processes and properties of microorganisms, including ARCHAEA; BACTERIA; RICKETTSIA; VIRUSES; FUNGI; and others.Amino Acids: Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins.Chromatography, Paper: An analytical technique for resolution of a chemical mixture into its component compounds. Compounds are separated on an adsorbent paper (stationary phase) by their varied degree of solubility/mobility in the eluting solvent (mobile phase).Fetuins: A family of calcium-binding alpha-globulins that are synthesized in the LIVER and play an essential role in maintaining the solubility of CALCIUM in the BLOOD. In addition the fetuins contain aminoterminal cystatin domains and are classified as type 3 cystatins.Binding Sites: The parts of a macromolecule that directly participate in its specific combination with another molecule.Influenza A virus: The type species of the genus INFLUENZAVIRUS A that causes influenza and other diseases in humans and animals. Antigenic variation occurs frequently between strains, allowing classification into subtypes and variants. Transmission is usually by aerosol (human and most non-aquatic hosts) or waterborne (ducks). Infected birds shed the virus in their saliva, nasal secretions, and feces.Glycomics: The systematic study of the structure and function of the complete set of glycans (the glycome) produced in a single organism and identification of all the genes that encode glycoproteins.Amino Acid Sequence: The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.Sialomucins: A subcategory of mucins that contain SIALIC ACID.Cattle: Domesticated bovine animals of the genus Bos, usually kept on a farm or ranch and used for the production of meat or dairy products or for heavy labor.Protein Binding: The process in which substances, either endogenous or exogenous, bind to proteins, peptides, enzymes, protein precursors, or allied compounds. Specific protein-binding measures are often used as assays in diagnostic assessments.Hemagglutination, Viral: Agglutination of ERYTHROCYTES by a virus.alpha-Fetoproteins: The first alpha-globulins to appear in mammalian sera during FETAL DEVELOPMENT and the dominant serum proteins in early embryonic life.Carbohydrate Metabolism: Cellular processes in biosynthesis (anabolism) and degradation (catabolism) of CARBOHYDRATES.Chromatography, Gel: Chromatography on non-ionic gels without regard to the mechanism of solute discrimination.Peptide-N4-(N-acetyl-beta-glucosaminyl) Asparagine Amidase: An amidohydrolase that removes intact asparagine-linked oligosaccharide chains from glycoproteins. It requires the presence of more than two amino-acid residues in the substrate for activity. This enzyme was previously listed as EC perfringens: The most common etiologic agent of GAS GANGRENE. It is differentiable into several distinct types based on the distribution of twelve different toxins.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)Kinetics: The rate dynamics in chemical or physical systems.Periodic Acid-Schiff Reaction: A histochemical technique for staining carbohydrates. It is based on PERIODIC ACID oxidation of a substance containing adjacent hydroxyl groups. The resulting aldehydes react with Schiff reagent to form a colored product.Agglutination: The clumping together of suspended material resulting from the action of AGGLUTININS.G(M2) Ganglioside: A glycosphingolipid that accumulates due to a deficiency of hexosaminidase A or B (BETA-N-ACETYLHEXOSAMINIDASES), or GM2 activator protein, resulting in GANGLIOSIDOSES, heredity metabolic disorders that include TAY-SACHS DISEASE and SANDHOFF DISEASE.Substrate Specificity: A characteristic feature of enzyme activity in relation to the kind of substrate on which the enzyme or catalytic molecule reacts.Mass Spectrometry: An analytical method used in determining the identity of a chemical based on its mass using mass analyzers/mass spectrometers.Enterovirus D, Human: A species of ENTEROVIRUS infecting humans and consisting of 2 serotypes: Human enterovirus 68 and Human enterovirus 70.Sulfuric Acids: Inorganic and organic derivatives of sulfuric acid (H2SO4). The salts and esters of sulfuric acid are known as SULFATES and SULFURIC ACID ESTERS respectively.Polysaccharides, Bacterial: Polysaccharides found in bacteria and in capsules thereof.Lactose: A disaccharide of GLUCOSE and GALACTOSE in human and cow milk. It is used in pharmacy for tablets, in medicine as a nutrient, and in industry.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.Transferases: Transferases are enzymes transferring a group, for example, the methyl group or a glycosyl group, from one compound (generally regarded as donor) to another compound (generally regarded as acceptor). The classification is based on the scheme "donor:acceptor group transferase". (Enzyme Nomenclature, 1992) EC 2.Erythrocyte Membrane: The semi-permeable outer structure of a red blood cell. It is known as a red cell 'ghost' after HEMOLYSIS.Orthomyxoviridae: A family of RNA viruses causing INFLUENZA and other diseases. There are five recognized genera: INFLUENZAVIRUS A; INFLUENZAVIRUS B; INFLUENZAVIRUS C; ISAVIRUS; and THOGOTOVIRUS.Galactose Oxidase: An enzyme that oxidizes galactose in the presence of molecular oxygen to D-galacto-hexodialdose. It is a copper protein. EC gastroenteritis virus: A species of CORONAVIRUS causing a fatal disease to pigs under 3 weeks old.Receptors, Mitogen: Glycoprotein molecules on the surface of B- and T-lymphocytes, that react with molecules of antilymphocyte sera, lectins, and other agents which induce blast transformation of lymphocytes.Hemagglutinins, Viral: Specific hemagglutinin subtypes encoded by VIRUSES.Acetylglucosamine: The N-acetyl derivative of glucosamine.Starfish: Echinoderms having bodies of usually five radially disposed arms coalescing at the center.Glycosides: Any compound that contains a constituent sugar, in which the hydroxyl group attached to the first carbon is substituted by an alcoholic, phenolic, or other group. They are named specifically for the sugar contained, such as glucoside (glucose), pentoside (pentose), fructoside (fructose), etc. Upon hydrolysis, a sugar and nonsugar component (aglycone) are formed. (From Dorland, 28th ed; From Miall's Dictionary of Chemistry, 5th ed)Borohydrides: A class of inorganic or organic compounds that contain the borohydride (BH4-) anion.Isoelectric Focusing: Electrophoresis in which a pH gradient is established in a gel medium and proteins migrate until they reach the site (or focus) at which the pH is equal to their isoelectric point.alpha-N-Acetylgalactosaminidase: A hexosaminidase with specificity for terminal non-reducing N-acetyl-D-galactosamine residues in N-acetyl-alpha-D-galactosaminides.Asparagine: A non-essential amino acid that is involved in the metabolic control of cell functions in nerve and brain tissue. It is biosynthesized from ASPARTIC ACID and AMMONIA by asparagine synthetase. (From Concise Encyclopedia Biochemistry and Molecular Biology, 3rd ed)Hemagglutinins: Agents that cause agglutination of red blood cells. They include antibodies, blood group antigens, lectins, autoimmune factors, bacterial, viral, or parasitic blood agglutinins, etc.Distal Myopathies: A heterogeneous group of genetic disorders characterized by progressive MUSCULAR ATROPHY and MUSCLE WEAKNESS beginning in the hands, the legs, or the feet. Most are adult-onset autosomal dominant forms. Others are autosomal recessive.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.Capsid Proteins: Proteins that form the CAPSID of VIRUSES.Magnetic Resonance Spectroscopy: Spectroscopic method of measuring the magnetic moment of elementary particles such as atomic nuclei, protons or electrons. It is employed in clinical applications such as NMR Tomography (MAGNETIC RESONANCE IMAGING).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)Membrane Glycoproteins: Glycoproteins found on the membrane or surface of cells.Antigens, Differentiation, Myelomonocytic: Surface antigens expressed on myeloid cells of the granulocyte-monocyte-histiocyte series during differentiation. Analysis of their reactivity in normal and malignant myelomonocytic cells is useful in identifying and classifying human leukemias and lymphomas.Cricetulus: A genus of the family Muridae consisting of eleven species. C. migratorius, the grey or Armenian hamster, and C. griseus, the Chinese hamster, are the two species used in biomedical research.Liver: A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.Structure-Activity Relationship: The relationship between the chemical structure of a compound and its biological or pharmacological activity. Compounds are often classed together because they have structural characteristics in common including shape, size, stereochemical arrangement, and distribution of functional groups.Antibodies, Monoclonal: Antibodies produced by a single clone of cells.Species Specificity: The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.Symporters: Membrane transporters that co-transport two or more dissimilar molecules in the same direction across a membrane. Usually the transport of one ion or molecule is against its electrochemical gradient and is "powered" by the movement of another ion or molecule with its electrochemical gradient.Epitopes: Sites on an antigen that interact with specific antibodies.GalactosamineSwine: Any of various animals that constitute the family Suidae and comprise stout-bodied, short-legged omnivorous mammals with thick skin, usually covered with coarse bristles, a rather long mobile snout, and small tail. Included are the genera Babyrousa, Phacochoerus (wart hogs), and Sus, the latter containing the domestic pig (see SUS SCROFA).Cell Adhesion Molecules: Surface ligands, usually glycoproteins, that mediate cell-to-cell adhesion. Their functions include the assembly and interconnection of various vertebrate systems, as well as maintenance of tissue integration, wound healing, morphogenic movements, cellular migrations, and metastasis.Histocytochemistry: Study of intracellular distribution of chemicals, reaction sites, enzymes, etc., by means of staining reactions, radioactive isotope uptake, selective metal distribution in electron microscopy, or other methods.Antigens, CD43: A sialic acid-rich protein and an integral cell membrane mucin. It plays an important role in activation of T-LYMPHOCYTES.Trypsin: A serine endopeptidase that is formed from TRYPSINOGEN in the pancreas. It is converted into its active form by ENTEROPEPTIDASE in the small intestine. It catalyzes hydrolysis of the carboxyl group of either arginine or lysine. EC A basic science concerned with the composition, structure, and properties of matter; and the reactions that occur between substances and the associated energy exchange.

Gangliosides of human kidney. (1/2052)

Five gangliosides isolated from human kidney have been characterized. The two main fractions were shown to be typical extraneural gangliosides in having lactose as their neutral carbohydrate moiety. Their structures were identified as: AcNeu(alpha2-3)Gal(beta1-4)Glc(beta1-1)Cer and AcNeu(alpha2-8)AcNeu(alpha2-3)Gal(beta1-4)Glc(beta1-1)Cer. The two main hexosamine-containing gangliosides are structurally related to human blood group substances of glycosphingolipid nature. The following structures are postulated: AcNeu(alpha2-3)Gal(beta1-4)GlcNAc(beta1-3)Gal(beta1-4)Glc(beta1-1)Cer and AcNeu(alpha2-3)Gal(beta1-4)[Fuc(alpha1-3)]GlcNAc(beta1-3)Gal(beta1-4)Glc(beta1-1) Cer. The third hexosamine-containing ganglioside belongs to a different series of glycolipids and was shown to have the structure of a major ganglioside of human brain: AcNeu(alpha2-3)Gal(beta1-3)GalNAc(beta1-4)[AcNeu(alpha2-3)]Gal(beta1-4)Glc(beta1- 1)Cer. The fatty acid structure of different gangliosides was shown to resemble that of neutral glycolipids of human kidney with the nonhydroxy acids C16:0, C22:0, and C24:0 as major components.  (+info)

Acid-catalyzed lactonization of alpha2,8-linked oligo/polysialic acids studied by high performance anion-exchange chromatography. (2/2052)

Recent studies from many laboratories revealed remarkable structural, distributional, and functional diversities of oligo/polysialic acids (OSA/PSA) that exist in organisms ranging from bacteria to man. These diversities are further complicated by the fact that OSA/PSA spontaneously form lactones under even mildly acidic conditions. By using high performance anion-exchange chromatography (HPAEC) with nitrate eluents, we found that lactonization of alpha2,8-linked OSA/PSA (oligo/poly-Neu5Ac, oligo/poly-Neu5Gc and oligo/poly-KDN) proceeds readily, and the lactonization process displays three discrete stages. The initial stage is characterized by limited lactonization occurring between two internal sialic acid residues, reflected by a regular pattern of lactone peaks interdigitated with non-lactonized peaks on HPAEC. In the middle stage, multiple lactonized species are formed from a molecule with a given degree of polymerization (DP), in which the maximum number of lactone rings formed equals DP minus 2. At the final stage, completely lactonized species become the major components, resulting in drastic changes in the physicochemical properties of the sample. Interestingly, the smallest lactonizable OSA are tetramer, trimer, and dimer at the initial, middle, and final stages, respectively. At any of the stages, OSA/PSA of higher DP lactonize more rapidly, but all the lactone rings rapidly open up when exposed to mild alkali. Lactonized OSA/PSA are resistant to both enzyme- and acid-catalyzed glycosidic bond cleavage. The latter fact was utilized to obtain more high DP oligo/poly(alpha2,8-Neu5Gc) chains from a polysialoglycoprotein. Our results should be useful in preparation, storage, and analysis of OSA/PSA. Possible biological significance and bioengineering potentials of lactonization are discussed.  (+info)

Carbohydrate on human factor VIII/von Willebrand factor. Impairment of function by removal of specific galactose residues. (3/2052)

Human factor VIII/von Willebrand factor protein containing 120 +/- 12 nmol of sialic acid and 135 +/- 13 nmol of galactose/mg of protein was digested with neuraminidase. The affinity of native factor VIII/von Willebrand factor and its asialo form for the hepatic lectin that specifically binds asialoglycoproteins was assessed from in vitro binding experiments. Native factor VIII/von Willebrand factor exhibited negligible affinity while binding of the asialo derivative was comparable to that observed for asialo-alpha1-acid glycoprotein. Incubation of asialo-factor VIII/von Willebrand factor with Streptococcus pneumoniae beta-galactosidase removed only 62% of the galactose but abolished binding to the purified hepatic lectin. When the asialo derivative was incubated with purified beta-D-galactoside alpha2 leads to 6 sialyltransferase and CMP-[14C]NeuAc, only 61% of the galactose incorporated [14C]NeuAc. From the known specificites of these enzymes, it is concluded that galactose residues important in lectin binding are present in a terminal Gal/beta1 leads to 4GlcNAc sequence on asialo-factor VIII/von Willebrand factor. The relative ristocetin-induced platelet aggregating activity of native, asialo-, and agalacto-factor VIII/von Willebrand factor was 100:38:12, respectively, while procoagulant activity was 100:100:103.  (+info)

Stable thiobarbituric acid chromophore with dimethyl sulphoxide. Application to sialic acid assay in analytical de-O-acetylation. (4/2052)

With dimethyl sulphoxide instead of butanol in the thiobarbituric acid assay for sialic acid, a non-fading chromophore with lambdamax. = 549 nm was produced in a homogeneous solution, allowing dilution of the test mixture in case of high colour yield. This test adapted well to studies on alkaline de-O-acetylation. Bovine and rat submaxillary mucins, and rabbit Tamm-Horsfall urinary sialoproteins contain O-acetyl isomers of neuramine acid that are resistant to the thiobarbituric acid assay. Alkaline de-O-acetylation converted resistant O-acetylneuraminic acid into thiobarbituric acid-reactive sialic acid, and such conversion paralleled de-O-acetylation as measured by the ferric hydroxamate method. The colour increment was similar when the alkaline treatment of bovine submaxillary mucin either preceded or followed the acid hydrolysis. Only alkaline preptreatment was effective with rat submaxillary mucin. By selecting optimal conditions for alkaline de-O-acetylation, O-acetyl isomers can be accurately assessed by the thiobarbituric acid assay.  (+info)

Differential expression of alpha2-6 sialylated polylactosamine structures by human B and T cells. (5/2052)

We found that human peripheral B and T cells differed in the surface expression of alpha2-6 sialylated type 2 chain glycans. In contrast to B cells, T cells expressed only sialoglycans with repeated N-acetyllactosamine (Galss1-4GlcNAc) disaccharides. This finding was based on the specificity of the monoclonal antibodies HB6, HB9 (CD24), HD66 (CDw76), FB21, and CRIS4 (CDw76) with the alpha2-6 sialylated model gangliosides IV6NeuAcnLc4Cer (2-6 SPG), VI6NeuAcnLc6Cer (2-6 SnHC), VIII6NeuAcnLc8Cer (2-6 SnOC), and X6NeuAcnLc10Cer (2-6 SnDC). We found that, in addition to their common requirement of an alpha2-6 bound terminal sialic acid for binding, the antibodies displayed preferences for the length of the carbohydrate backbones. Some of them bound mainly to 2-6 SPG with one N-acetyllactosamine (LacNAc) unit (HB9, HD66); others preferentially to 2-6 SnHC and 2-6 SnOC, with two and three LacNAc units, respectively (HB6 and FB21); and one of them exclusively to very polar alpha2-6 sialylated type 2 chain antigens (CRIS4) such as to 2-6 SnOC and even more polar gangliosides with three and more LacNAc units. These specificities could be correlated with the cellular binding of the antibodies as follows: whereas all antibodies bound to human CD 19 positive peripheral B cells, their reactivity with CD3 positive T cells was either nearly lacking (HD66, HB9), intermediate (about 65%: HB6, FB21) or strongly positive (CRIS4, 95%). Thus, the binding of the antibodies to 2-6 sialylated glycans with multiple lactosamine units appeared to determine their binding to T-cells.  (+info)

Amino acid substitutions in a conserved region in the stalk of the Newcastle disease virus HN glycoprotein spike impair its neuraminidase activity in the globular domain. (6/2052)

The ectodomain of the paramyxovirus haemagglutinin-neuraminidase (HN) glycoprotein spike can be divided into two regions: a membrane-proximal, stalk-like structure and a terminal globular domain. The latter contains all the antibody recognition sites of the protein, as well as its receptor recognition and neuraminidase (NA) active sites. These two activities of the protein can be separated by monoclonal antibody functional inhibition studies and mutations in the globular domain. Herein, we show that mutation of several conserved residues in the stalk of the Newcastle disease virus HN protein markedly decrease its NA activity without a significant effect on receptor recognition. Thus, mutations in the stalk, distant from the NA active site in the globular domain, can also separate attachment and NA. These results add to an increasing body of evidence that the NA activity of this protein is dependent on an intact stalk structure.  (+info)

Regulation of capsular polysialic acid biosynthesis by temperature in Pasteurella haemolytica A2. (7/2052)

The capsular polysaccharide of Pasteurella haemolytica A2 consists of a linear polymer of N-acetylneuraminic acid (Neu5Ac) with alpha(2-8) linkages. The production of this polymer is strictly regulated by the growth temperature and above 40 degrees C no production is detected. Analysis of the enzymatic activities directly involved in its biosynthesis reveals that Neu5Ac lyase, CMP-Neu5Ac synthetase and polysialyltransferase are involved in this regulation. Very low activities were found in P. haemolytica grown at 43 degrees C (at least 25 times lower than those observed when the growth temperature was 37 degrees C). The synthesis of these enzymes increased rapidly when bacteria grown at 43 degrees C were transferred to 37 degrees C and decreased dramatically when cells grown at 37 degrees C were transferred to 43 degrees C. These findings indicate that the cellular growth temperature regulates the synthesis of these enzymes and hence the concentration of the intermediates necessary for capsular polysaccharide genesis in P. haemolytica A2.  (+info)

Free sialic acid levels in the cerebrospinal fluid of patients with meningitis. (8/2052)

The free and bound sialic acid content of cerebrospinal fluid from patients with positive evidence (by CSF culture) of pyogenic and tuberculous meningitis was determined. The free sialic acid content was significantly raised only in cases of pyogenic meningitis, but not in tuberculous or other types of the disease.  (+info)

  • Phylogeny of selected sialic acid aldolase (NanA), epimerase (NanE), and kinase (NanK) polypeptides involved in microbial sialic acid catabolism. (
  • The cluster of genes encoding the enzymes N -acetylneuraminate lyase (NanA), epimerase (NanE), and kinase (NanK), necessary for the catabolism of sialic acid (the Nan cluster), are confined 46 bacterial species, 42 of which colonize mammals, 33 as pathogens and 9 as gut commensals. (
  • The catabolic pathway of sialic acid involves several steps beginning with NanA. (
  • The DSLA-100 assay kit is based on the oxidation of sialic acid with periodate and detection of the reaction product formyl pyruvic acid with thiobarbituric acid.The ESLA-100 assay kit is based on enzymatic digestion of sialic acid with NANA-aldolase (N-acetyl-neuraminic acid aldolase) and detection of the breakdown product pyruvate. (
  • Structures of sialic acid ( NANA ) and its deaminated form ( KDN ). (
  • Defective free sialic acid transport can be established by quantitative analysis of NANA in urine relative to the concentration of creatinine. (
  • We determined the crystal structure of the globular head region of SosV-RBP, revealing that while the glycoprotein presents a classical paramyxoviral six-bladed β-propeller fold and structurally classifies in close proximity to paramyxoviral RBPs with hemagglutinin-neuraminidase (HN) functionality, it presents a receptor-binding face incongruent with sialic acid recognition. (
  • Hemadsorption and neuraminidase activity analysis confirms the limited capacity of SosV-RBP to interact with sialic acid in vitro and indicates that SosV-RBP undergoes a nonclassical route of host-cell entry. (
  • For determination of TSA an enzymatic (neuraminidase) and a chemical (acid) hydrolysis were compared. (
  • Values of SA analyzed after neuraminidase- or acid hydrolysis treatment were comparable. (
  • In early work, the EV70 receptor on erythrocytes, responsible for its hemagglutinating activity, was shown to be sensitive to neuraminidase, implying an essential role for sialic acid in virus attachment. (
  • Radioactive gangliosides were isolated and selectively degraded with bacterial neuraminidase and rat liver beta-galactosidase to Tay-Sachs ganglioside-(3)H. Radioactivity in the labeled product was confined to the N-acetyl-neuraminic acid portion of the molecule. (
  • After preincubation with neuraminidase, which released 90-100% of the sialic acid from the membranes of the synaptic vesicles and the nerve endings, the electron-dense deposits marked the reaction sites of sulphate with CIH. (
  • The method described allows the electron-microscopical demonstration of acid-resistant, neuraminidase-sensitive sialic acid in synaptic structures and the discrimination from sulphated mucopolysaccharides. (
  • The neuraminidase of 2007-2008 A(H1N1) viruses has an increased affinity for sialic acids as compared with the N1 of previously circulating viruses. (
  • Using site-directed mutagenesis analysis and an enzymatic assay on cells transiently expressing the viral neuraminidase, the amino acid changes that could account for the particular enzymatic properties of the neuraminidase of 2007-2008 A(H1N1) viruses were explored. (
  • Enzymic treatment with Vibrio cholerae neuraminidase demonstrated that sialic acid was a major determinant of virus binding. (
  • There are receptor families that specifically recognize sialoglycans such as selectins or sialic acid-binding immunoglobulin-like lectins (Siglecs). (
  • Through investigation of the virion envelope-displayed SosV host-cell receptor binding protein, we provide a molecular-level rationale for how SosV undergoes a sialic acid-independent host-cell entry pathway, which contrasts the glycan reliance of related orthorubulaviruses, including mumps virus. (
  • Due to its position at the non-reducing termini of oligo-and polysaccharides, as well as its unique chemical characteristics, sialic acid is involved in a multitude of different receptor-ligand interactions. (
  • Angata T, Hayakawa T, Yamanaka M, Varki A, Nakamura M (2006) Discovery of Siglec-14, a novel sialic acid receptor undergoing concerted evolution with Siglec-5 in primates. (
  • We have shown recently that adenovirus types 8, 19a, and 37, which are the major causes of epidemic keratoconjunctivitis, use sialic acid rather than CAR as a major cellular receptor. (
  • Human adenovirus type 26 uses sialic acid as a primary cellular receptor-structural insights for this phase 3 vaccine vector. (
  • The soluble sialoadhesin could bind PRRSV in a sialic acid-dependent manner and could neutralize PRRSV infection of macrophages, thereby confirming the role of sialoadhesin as an essential PRRSV receptor on macrophages. (
  • Human erythrocyte band 3 functions as a receptor for the sialic acid-independent invasion of Plasmodium falciparum. (
  • Adenovirus type 37 uses sialic acid as a cellular receptor. (
  • As we discussed previously , attachment of all influenza A virus strains to cells requires sialic acids. (
  • However, there are a number of chemically different forms of sialic acids, and influenza virus strains vary in their affinity for them. (
  • Avian influenza virus strains preferentially bind to sialic acids attached to galactose via an alpha(2,3) linkage. (
  • In contrast, human influenza virus strains preferentially attach to sialic acids attached to galactose by an alpha(2,6) linkage. (
  • For example, highly pathogenic avian H5N1 influenza viruses undergo limited replication in the human respiratory tract due to the presence of some cells with alpha(2,3) linked sialic acids. (
  • Consistent with this hypothesis, the results of studies of early influenza virus isolates from the 1918, 1957, and 1968 pandemics suggest that these viruses preferentially recognized alpha(2,6) linked sialic acids. (
  • Conclusions- Total serum sialic acid levels were significantly elevated in a relatively small group of NIDDM patients and were correlated with hypertension and retinopathy. (
  • At screening, blood samples were taken from nonfasting participants, and serum sialic acid levels were measured by automatic analyzer. (
  • The recent discovery that human noroviruses (huNoVs) recognize sialic acids (SAs) in addition to histo-blood group antigens (HBGAs) pointed to a new direction in studying virus-host interactions during calicivirus infection. (
  • However, efficient human to human transmission requires that the avian viruses recognize sialic acids with alpha(2,6) linkages. (
  • It is well known that erythrocytes have a large amount of sialic acid and could represent a model to investigate changes occurring in a pathology like stroke. (
  • DESIGN: Piglets (n = 54) were allocated to 1 of 4 groups fed sow milk replacer supplemented with increasing amounts of sialic acid as casein glycomacropeptide for 35 d. (
  • Predicted to have monosaccharide binding activity and sialic acid binding activity. (
  • and that (iv) the ability of adenovirus knobs to interact with sialic acid correlates with the overall charge on the top surface of the respective knobs as predicted by homology modeling. (
  • Using a combination of transcriptomic and functional genomic approaches, we identified a gene cluster dedicated to the uptake and metabolism of sialic acid. (
  • Kit Contents: Sufficient reagent A, reagent B, buffer solution, stabilizer and standard serum for the measurement of sialic acid in serum. (
  • Second, because the measurement of sialic acid was done in the 1960s, another sialated protein may have been measured. (
  • 1) An inherited condition characterised by an accumulation of sialic acid, primarily in the nervous system, with a wide range of signs and symptoms. (
  • Sialic acid storage diseases (SSDs) are severe autosomal recessive neurodegenerative disorders caused by a transport defect across the lysosomal membrane, which leads to accumulation of sialic acid in tissues, fibroblasts, and urine. (
  • Monosaccharide and sialic acid analysis is applicable to all stages of biopharmaceutical development and manufacturing processes including cell line and clone selection, upstream and downstream process development and manufacturing in-process control, batch consistency and release. (
  • Our workflow delivers trace performance for monosaccharides and sialic acids without cumbersome and time consuming labeling protocols. (
  • The versatile Dionex ICS-6000 Hybrid HPIC System is a complete solution for the biopharma carbohydrate applications (monosaccharides, disaccharides, sialic acids, N - and O -linked oligosaccharide analysis, and more). (
  • Sialic acids are a group of monosaccharides with a nine-carbon backbone, commonly found in mammalian cells and pathogenic bacteria, and frequently described to protect EPS molecules and cells from attack by proteases or glycosidases. (
  • Varki, A. and Diaz, S. (1984) The release and purification of sialic acids from glycoconjugates: methods to minimize the loss and migration of O -acetyl groups. (
  • HPAE-PAD, used mainly for the analysis of sialic acids released from glycoconjugates, can reduce the possibility of interferences by relatively long gradient separations. (
  • For it to become active to enter in the oligosaccharide biosynthesis process of the cell, a monophosphate nucleoside is added, which comes from a cytidine triphosphate, turning sialic acid into cytidine monophosphate-sialic acid (CMP-sialic acid). (
  • Product Information for Cytidine-5′-monophospho-N-acetylneuraminic acid sodium-Sigma Aldrich. (
  • The production of cytidine 5'-monophosphate N-acetylneuraminic acid (CMP-NeuAc) and CMP-9-azido-NeuAc using crude CSS was successful with >90% conversion at scales from 100 mg to 5 g. (
  • Functional studies included biochemical assays for N-glycosylation and mucin-type O-glycosylation and SLC35A1-encoded cytidine 5'-monophosphosialic acid (CMP-sialic acid) transport after heterologous expression in yeast. (
  • p>This subsection of the 'Function' section describes the interaction between a single amino acid and another chemical entity. (
  • D ) Comparison of the amino acid sequences of NPL in human (Q9BXD5.1), zebrafish (CAP19481.1), mouse (NP_083025.1), dog (XP_005622466.1), chicken (NP_001026731.1, Xenopus (NP_001011207.1), and alpaca (XP_015101171.1), as well as 2 mutants. (
  • In summary, we have characterized a novel sialate-O-acetylesterase that contributes to siallobiology of this important human pathogen and has potential applications in analysis of sialic acid diacetylation of biologics in the pharmaceutical industry. (
  • The importance of sialic acid biosynthesis in human physiology is well illustrated by the severe metabolic disorders in this pathway. (
  • Sialic acids comprise a family of more than 50 carbohydrates that share a nine-carbon backbone (C1-9) to which specific chemical modifications are enzymatically attached inside the cell. (
  • Here, we explored two alternative strategies for radiolabeling Siglec-9 peptide using a 1,4,7-triazacyclononane-triacetic acid (NOTA)-chelator to bind [ 68 Ga]Ga or [ 18 F]AlF. (
  • Sialic acid storage diseases (SSDs) (3) are autosomal recessive neurodegenerative disorders that may present as a severe infantile form, infantile sialic acid storage disease (ISSD), or as a slowly progressive adult form that is prevalent in the Finnish population, called Salla disease (1). (
  • Here, the contribution of some H. pylori virulence factors, the blood group antigen-binding adhesin BabA, the sialic acid-binding adhesin SabA, the neutrophil-activating protein HP-NAP, and the vacuolating cytotoxin VacA, to the activation of human neutrophils in terms of adherence, phagocytosis, and oxidative burst was investigated. (
  • Sialic acids play important roles in many physiological and pathological processes via carbohydrate-protein interactions, including cell-cell communication, bacterial and viral infections. (
  • CONCLUSIONS: Feeding a protein-bound source of sialic acid during early development enhanced learning and increased expression of 2 genes associated with learning in developing piglets. (
  • A method, such as the one presented here, that can detect these subtle differences, α2,3 versus α2,6-linked sialic acids, at the glycosylation site of the resident protein can provide an important tool to better understand the role of sialic acids in such biological processes. (
  • Here we report the use of gold nanoparticles functionalised with a sialic acid ligand diluted with a polyethylene glycol (PEG) ligand for the plasmonic detection of a soluble form of murine Siglec-E (mSiglec-E-Fc fusion protein) and, importantly, for the specific detection of the same Siglec expressed on the surface of mammalian cells. (
  • The gold nanoparticles were functionalised with various ratios of sialic acid:PEG ligands and the optimum ratio for the detection of murine Siglec-E was established based on the plasmonic detection of the soluble pre-complexed recombinant form of murine Siglec-E (mSiglec-E-Fc fusion protein). (
  • The optimum ratio for the detection of the fusion protein was found to be sialic acid:PEG ligands in a 50:50 ratio (glyconanoparticles 1). (
  • Therefore the primary objective of this thesis was the generation and characterisation of recombinant antisialic acid antibodies.A single-chain antibody fragment (scFv) library was constructed from a chicken that was immunised with a novel synthetic sialic acid protein-conjugate (Neu5Gchumanserum albumin). (
  • First, it is unclear whether any hypothesis about sialic acid had been set out by the investigators 20 years ago or whether this was part of the series of protein measurements that was done without a particular hypothesis. (
  • The ability of the HA protein to differentiate sialic acid linkages makes it an interesting candidate for use in the characterization of glycoprotein's potentially facilitating the discrimination of alternate glycoforms of biopharmaceutical therapeutics and their subsequent purification. (
  • The sulphate groups which were present at a concentration of 2.3 and 2.2 µmol/mg protein for the synaptic vesicle and nerve ending membrane preparations, respectively, were rendered soluble as methyl monosulphate by trans-esterification with acid/methanol and quantitatively removed from the structures. (
  • A rapid and nondestructive method for determining the distribution map of protein content (PC), carbohydrate content (CC) and sialic acid content (SAC) on EBN sample was proposed. (