Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.4.99.7 (sialyltransferase)
 1,534 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

[reaction: see text] beta-D-Galp-(1-->9)-D-KDN, a disaccharide component of the cell wall of Streptomyces sp. MB-8, was synthesized from beta-D-Galp-(1-->6)-D-Manp and pyruvate using a sialic acid aldolase. The obtained KDN-containing compound was a novel acceptor for bacterial sialyltransferases. Unusual alpha2,3- and alpha2,6-linked sialyltrisaccharides and a tetrasaccharide were synthesized using a one-pot two-enzyme system containing a Neisseria meningitidis CMP-sialic acid synthetase and a Pasteurella multocida sialyltransferase or a Photobacterium damsela alpha2,6-sialyltransferase.
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PMID:Aldolase-catalyzed synthesis of beta-D-galp-(1-->9)-D-KDN: a novel acceptor for sialyltransferases. 1670 34

In order to understand the biological importance of naturally occurring sialic acid variations on disialyl structures in nature, we developed an efficient two-step multienzyme approach for the synthesis of a series of GD3 ganglioside oligosaccharides and other disialyl glycans containing a terminal Siaalpha2-8Sia component with different natural and non-natural sialic acids. In the first step, alpha2-3- or alpha2-6-linked monosialylated oligosaccharides were obtained using a one-pot three-enzyme approach. These compounds were then used as acceptors for the alpha2-8-sialyltransferase activity of a recombinant truncated multifunctional Campylobacter jejuni sialyltransferase CstII mutant, CstIIDelta32(I53S), to produce disialyl oligosaccharides. The alpha2-8-sialyltransferase activity of CstIIDelta32(I53S) has promiscuous donor substrate specificity and can tolerate various substitutions at C-5 or C-9 of the sialic acid in CMP-sialic acid, while its acceptor substrate specificity is relatively restricted. The terminal sialic acid residues in the acceptable monosialylated oligosaccharide acceptors are restricted to Neu5Ac, Neu5Gc, KDN, and some of their C-9-modified forms but not their C-5 derivatives. The disialyl oligosaccharides obtained are valuable probes for their biological studies.
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PMID:Chemoenzymatic synthesis of GD3 oligosaccharides and other disialyl glycans containing natural and non-natural sialic acids. 1994 30

In higher vertebrates, sialyltransferases catalyze the transfer of sialic acid residues, either Neu5Ac or Neu5Gc or KDN from an activated sugar donor, which is mainly CMP-Neu5Ac in human tissues, to the hydroxyl group of another saccharide acceptor. In the human genome, 20 unique genes have been described that encode enzymes with remarkable specificity with regards to their acceptor substrates and the glycosidic linkage formed. A systematic search of sialyltransferase-related sequences in genome and EST databases and the use of bioinformatic tools enabled us to investigate the evolutionary history of animal sialyltransferases and propose original models of divergent evolution of animal sialyltransferases. In this chapter, we extend our phylogenetic studies to the comparative analysis of the environment of sialyltransferase gene loci (synteny and paralogy studies), the variations of tissue expression of these genes and the analysis of amino-acid position evolution after gene duplications, in order to assess their sequence-function relationships and the molecular basis underlying their functional divergence.
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PMID:A practical approach to reconstruct evolutionary history of animal sialyltransferases and gain insights into the sequence-function relationships of Golgi-glycosyltransferases. 2376 55