Structure of human ST8SiaIII sialyltransferase provides insight into cell-surface polysialylation.
Volkers, G., Worrall, L.J., Kwan, D.H., Yu, C.C., Baumann, L., Lameignere, E., Wasney, G.A., Scott, N.E., Wakarchuk, W., Foster, L.J., Withers, S.G., Strynadka, N.C.(2015) Nat Struct Mol Biol 22: 627-635
- PubMed: 26192331 
- DOI: https://doi.org/10.1038/nsmb.3060
- Primary Citation of Related Structures:  
5BO6, 5BO7, 5BO8, 5BO9 - PubMed Abstract: 
Sialyltransferases of the mammalian ST8Sia family catalyze oligo- and polysialylation of surface-localized glycoproteins and glycolipids through transfer of sialic acids from CMP-sialic acid to the nonreducing ends of sialic acid acceptors. The crystal structure of human ST8SiaIII at 1.85-Å resolution presented here is, to our knowledge, the first solved structure of a polysialyltransferase from any species, and it reveals a cluster of polysialyltransferase-specific structural motifs that collectively provide an extended electropositive surface groove for binding of oligo-polysialic acid chain products. The ternary complex of ST8SiaIII with a donor sugar analog and a sulfated glycan acceptor identified with a sialyltransferase glycan array provides insight into the residues involved in substrate binding, specificity and sialyl transfer.
Organizational Affiliation: 
1] Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, British Columbia, Canada. [2] Centre for Blood Research, University of British Columbia, Vancouver, British Columbia, Canada.