Sialyltransferases

Yu, H. and Chen, X. (2006) Aldolase-catalyzed synthesis of beta-D-Gal-(l-9)-D-KDN a novel acceptor for sialyltransferases. Organic Letters, 8, 2393-2396. 

Haraguchi, M., Yamashiro, S., Yamamoto, A., Fumkawa, K., Takamiya, K., Lloyd, K. O., Shiku, H., and Fumkawa, K., 1994, Isolation ofGD3 synthasegene by expression cloning ofGM3 a-2,8-sialyltransferase cDNA using anti-GD2 monoclonal antibody. Proc. Natl. Acad. Sci. USA 91 10455-10459. 

Scheme 10.3 Ceramide glycanase mediated release by transglycosylation. a) Pd/C, MeOH b) (8), EEDQ, EtOH-CgHe c) MeONa d) CH2=CHCONH2, TMEDA, APS, DMSO-H2O, 50"C, CMP-NeuAc, a-2,3-sialyltransferase, BSA, MnCb, CIAP, 50 nM sodium cacodylate buffer, pH 7.49, ceramide, Triton CF-54, sodium citrate buffer, pH 6.0, 37°C, 61%.

Cytidine 5 -phospho-A-acetylneuraminate (298), the coenzyme of sialyltransferases, is a sugar-nucleotide in which the leaving group is a nucleotidyl monophosphate that contains a carboxylate group directly attached to the anomeric centre. Studies of its hydrolysis reveal that at pH 5 specific acid catalysis occurs (Scheme 34) to yield a glycosyl carbocation as a tight ion pair, the lifetime of which was estimated... 

Example 5 Hayakawa and Noyori group in their studies on new activators for phosphoroamidite coupling reactions have applied the most effective member of the group of acid/azole complexes AT-(phenyl)imidazolium tri-flate (N-PhIMT) in the efficient synthesis of biologically important compounds [20j]. A noteworthy example is synthesis of cytidine-5 -monophos-pho-AT-acetylneuraminic acid. This compound is a source of sialic acid in the sialyltransferase-catalysed biosynthesis of sialyl oligosaccharides [25]. 

This set of enzymes consists of those proteins that catalyze the transfer of sialyl moieties. (1) CMP-A-acetyl-neuraminate-j8-galactoside o -2,6-sialyltransferase [EC... 

OMP-N-acetyIneuraminate, SIALYLTRANSFERASE 0MP-N-acetylneuraminate-y3-galactoside a-2,6-si a lyltra nsferase, SIALYLTRANSFERASE... 

GALACTOSIDE FUCOSYLTRANSFERASES GALACTOSIDE SIALYLTRANSFERASES /3-D-Galactosyl-1,4-y3-D-glucosylceramide, SIALYLTRANSFERASE "GAMESS,"... 

LACTOSE SYNTHASE LACTOSE SYNTHASE Lactosylceramide a-2,6-N-sialyltransferase, SIALYLTRANSFERASE Lag phase in microtubule assembly, MICROTUBULE ASSEMBLY KINETICS Lag phase in polymerization,... 

Monosialoganglioside sialyltransferase, SIALYLTRANSFERASE MONTE CARLO METHODS MORE O FERRALL-JENCKS DIAGRAM... 

O-SIALOG LYCOPROTEASE SIALYLTRANSFERASE SIDE REACTIONS SIGMA (<7)... 

As an alternative to chemical sialylations, glycosyl transferases have been used to accomplish sialylations, particularly of N-linked glycopeptide building blocks (see also Section 6.3.1.1.5). The 2,3- and 2,6-sialyltransferases have been easily expressed in preparative amounts. Their use in glycopeptide building block synthesis is described in Section 6.3.3.6. 

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