Biomaterial Database

Enzymatic introduction of a fluorescent sialic acid into oligosaccharide chains of glycoproteins. 1988

H J Gross, and R Brossmer

Institut für Biochemie II, Universität Heidelberg, Federal Republic of Germany.

Aiming at the introduction of a fluorescent sialic acid into glycoconjugates, 5-acetamido-9-(3-fluoresceinylthio-ureido)-3,5,9-trideoxy-2-non ulosonic acid (9-fluoresceinyl-NeuAc) was synthesized which has an intact carbon chain. a) Despite the space-filling substituent at C-9, the fluorescent NeuAc analogue was activated to the corresponding CMP-glycoside by CMP sialic acid synthase from bovine brain. Whereas the Km value of the synthase was little affected by the modification (Km = 2.1 mM, for NeuAc Km = 1.4 mM), the V value decreased to 7.5%. b) CMP-9-fluoresceinyl-NeuAc was synthesized on a preparative scale (17% overall yield), and characterized by analytical HPLC, absorption and fluorescence spectra. c) 9-Fluoresceinyl-NeuAc was transferred onto asialo-alpha 1-acid glycoprotein by both Gal beta 1, 4GlcNAc alpha 2, 6sialyltransferase and Gal beta 1,4(3)GlcNAc alpha 2,3sialyltransferase (rat liver), and onto antifreeze glycoprotein by GalNAc alpha 2,6-sialyltransferase (porcine submaxillary glands). Using analytical HPLC, transfer was confirmed after release of the fluorescent sialic acid by Vibrio cholerae sialidase. d) Initial rate studies indicated a low Km value of Gal beta-1,4GlcNAc alpha 2,6sialyltransferase, and GalNAc alpha 2,6sialyltransferase (specific for O-linked oligosaccharide chains) for CMP-9-fluoresceinyl-NeuAc.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D008099	Liver	A large lobed glandular organ in the abdomen of vertebrates that is responsible for detoxification, metabolism, synthesis and storage of various substances.	Livers
D009713	Nucleotidyltransferases	A class of enzymes that transfers nucleotidyl residues. EC 2.7.7.	Nucleotidyltransferase
D009844	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.	Oligosaccharide
D005452	Fluoresceins	A family of spiro(isobenzofuran-1(3H),9'-(9H)xanthen)-3-one derivatives. These are used as dyes, as indicators for various metals, and as fluorescent labels in immunoassays.	Tetraiodofluorescein
D006023	Glycoproteins	Conjugated protein-carbohydrate compounds including MUCINS; mucoid, and AMYLOID glycoproteins.	C-Glycosylated Proteins,Glycosylated Protein,Glycosylated Proteins,N-Glycosylated Proteins,O-Glycosylated Proteins,Glycoprotein,Neoglycoproteins,Protein, Glycosylated,Proteins, C-Glycosylated,Proteins, Glycosylated,Proteins, N-Glycosylated,Proteins, O-Glycosylated
D000216	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 2.7.7.43.	Acylneuraminate Cytidylyltransferase,CMP Sialate Pyrophosphorylase,CMP Sialate Synthase,CMP-N-Acetylneuraminic Acid Synthetase,CMP-Sialic Acid Synthetase,Cytidine 5'-Monophosphosialic Acid Synthetase,Cytidine 5-Monophosphosialate Synthase,CMP N Acetylneuraminic Acid Synthetase,CMP Sialic Acid Synthetase,Cytidine 5 Monophosphosialate Synthase,Cytidine 5' Monophosphosialic Acid Synthetase,Cytidylyltransferase, Acylneuraminate,Cytidylyltransferase, N-Acylneuraminate,N Acylneuraminate Cytidylyltransferase,Pyrophosphorylase, CMP Sialate,Sialate Pyrophosphorylase, CMP,Sialate Synthase, CMP,Synthase, CMP Sialate,Synthase, Cytidine 5-Monophosphosialate,Synthetase, CMP-N-Acetylneuraminic Acid,Synthetase, CMP-Sialic Acid
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
D012794	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 Acids,Acids, N-Acetylneuraminic,Acids, Sialic,N Acetylneuraminic Acids
D012799	Sialyltransferases	A group of enzymes with the general activity 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.	Glycoprotein Sialyltransferases,Glycosyltransferase Family 29,Sialyltransferase,Ectosialyltransferase,Glycoprotein Sialyltransferase,Sialyltransferase, Glycoprotein,Sialyltransferases, Glycoprotein