A Novel α-2,6-Sialyltransferase:  Transfer of Sialic Acid to Fucosyl and Sialyl Trisaccharides

Abstract

The substrate specificity and enzymatic sialylation ability of the bacterium α-2,6-sialyltransferase were examined. The enzyme assay displayed a remarkable ability to catalyze sialyl transfer to type-II oligosaccharides possessing fucoside or sialoside at the 2 or 3 position of the terminal galactoside. Enzymatic syntheses were performed in order to confirm the structure of unusual assay products found when using Neu5Ac β2,3Galβ1,4Glc and Fuc α1,2Galβ1,4Glc as the sialyl acceptors. Both sialylation reactions (10 μmol scales) were run using 83 munits of enzyme, were complete in 2 h, and afforded the sialoside analogues Neu5Ac α2,6(Fuc α1,2) Galβ1,4Glc (88%) and Neu5Ac α2,6(Neu5Ac β2,3) Galβ1,4Glc (92%).

N-Terminal 112 amino acid residues are not required for the sialyltransferase activity of Photobacterium damsela α2,6-sialyltransferase

“…The flexible donor and acceptor substrate specificities of the enzyme were described and the enzyme was applied in the synthesis of α2,6-linked sialosides and glycopeptides (Yamamoto et al 1998a;Yu et al 2006;Yamamoto et al 1998b;Kajihara et al 1996;Teo et al 2005;Yamamoto et al 1996;Endo et al 2001). Pd2,6ST shares amino acid sequence homology with a multifunctional Pasteurella multocida sialyltransferase PmST1 encoded by gene Pm0188 (GenBank accession numbers: AAY89061, AAK02272) (Yu et al 2005), a Haemophilus ducreyi α2,3-sialyltransferase encoded by gene Hd0053 (GenBank accession number: AAP95068) (Li et al 2007), a Photobacterium phosphoreum α2,3-sialyltransferase encoded by gene pst3-467 (GenBank accession number: BAF63530) , and a Photobacterium leiognathi α2,6-sialyltransferase ).…”

Purification of Marine Bacterial Sialyltransferases and Sialyloligosaccharides

“…For example, it could transfer Neu5Ac to not only disaccharides but also mono-and tri-saccharides efficiently, and provided the corresponding sialosides ( Fig. 4; Kajihara et al, 1996;.…”

Chemoenzymatic Synthesis of Sialosides and Their Applications

“…Several non-natural ot2,6-linked sialosides 36-40 with azide or alkynemodified sialic acid residues were also prepared in excellent yields (86%-93%) from their C2-or C6-modified ManNAc or mannose bearing corresponding azide or alkyne functional groups 30-34 using the one-pot three-enzyme approach and GaipOMe (35) as an acceptor for Pd2,6ST (Scheme 5).…”