Sialyltransferases chains

Sialyltransferases transfer sialic acid moieties as the terminal residues in oligosaccharide side chains of animal cell coat proteins and gangliosides. In this assay, CMP-7V-acetylneuraminic acid was reacted with asialoglycoprotein to form cytidfne 5 -monophosphate (CMP) and the O-acetylneuraminic acid derivative of the protein. 

Livingston BD, Paulson JC (1993) Polymerase chain reaction cloning of a developmentally regulated member of the sialyltransferase gene family. J Biol Chem 268 11504-11507... 

The H3a,3e/NAc structural reporters of NeuSAc have proved to be suitable in studying sialylation reactions in terms of positional specificity and branching (N-linked carbohydrate chains) specificity, using different sialyltransferases and CMP-NeuSAc as donor [333-335] (see also section 6.3). 

In terms of preparative chemistry, the use of CMP- 3-Neu5Ac as a glycosyl donor and (cloned) a-2,3/6-sialyltransferases as biocatalysts have achieved a permanent position in the planning of synthetic routes for sialo-oligosaccharide chains see e.g. refs. [314,342, 345,351,472,473,535-544]. Especially in the field of the preparation of sialyl Le frag-... 

In breast cancer cells, the synthesis of 0-glycan core 1 and 2 structures occurs mainly in the cis—medial Golgi compartment with some overlap toward the medial Golgi. The sialyltransferase ST3Gal-I that acts on core 1 substrate has been shown to be localized by immunocytochemistry mainly to the medial and trans Golgi compartments in mammary cells. Its localization therefore partially overlaps with that of C2GnTl. Transfection experiments prove that the competition between the two enzymes indeed takes place. Thus the relative expression levels and activities of these two enzymes control the relative distribution of either highly sialylated or complex chains with core 2 structures of MUCl mucin. ... 

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