Glycosyltransferase families

Before the days of molecular cloning of glycosyltransferases the classification of these enzymes was based on common nucleotide-sugar donor substrate usage with sub-classification based on the linkage formed and the acceptor sugar used. 

Members within a family have extensive sequence identity at the amino acid level, which is often confined to specific boxes, and have one or more enzymatic properties in common. In the following paragraphs these glycosyltransferase families are discussed in more detail. 

Transferase family Linkage-type established Number of enzymes with sequence similarity Notes 

Sialyl a3-/a6-/a8-NeuAc to Gal(NAc)/NeuAc 17 All contain sialyl motif L and S 

P4-A- Acetylglucosaminyl P4-GlcNAc to Man 2 GlcNAcT IV is the only N-glycan branching GlcNAcT known so far that is not a stand alone  

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Bourne Y, Henrissat B. Glycoside hydrolases and glycosyltransferases families and functional modules. Curr. Opin. Struct. Biol. 33. 2001 11 593-600. 

The Arabidopsis P450, cytochrome bj, P450 reductase, and Glycosyltransferase Family 1 Site at PlaCe http //biobase.dk/P450/p450.shtml... 

Hefner, T. et al. (2002) Arbutin synthase, a novel member of the NRDlbeta glycosyltransferase family, is a unique multifunctional enzyme converting various natural products and xenobiotics. S/oorg. Med. Chem. 10, 1731-1741... 

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