title: Synthesis of biologically active N- and O-linked glycans with multisialylated poly-N-acetyllactosamine extensions using P. damsela α2-6 sialyltransferase.
abstract: Sialosides on N- and O-linked glycoproteins play a fundamental role in many biological processes, and synthetic glycan probes have proven to be valuable tools for elucidating these functions. Though sialic acids are typically found α2-3- or α2-6-linked to a terminal nonreducing end galactose, poly-LacNAc extended core-3 O-linked glycans isolated from rat salivary glands and human colonic mucins have been reported to contain multiple internal Neu5Acα2-6Gal epitopes. Here, we have developed an efficient approach for the synthesis of a library of N- and O-linked glycans with multisialylated poly-LacNAc extensions, including naturally occurring multisialylated core-3 O-linked glycans. We have found that a recombinant α2-6 sialyltransferase from Photobacterium damsela (Pd2,6ST) exhibits unique regioselectivity and is able to sialylate internal galactose residues in poly-LacNAc extended glycans which was confirmed by MS/MS analysis. Using a glycan microarray displaying this library, we found that Neu5Acα2-6Gal specific influenza virus hemagglutinins, siglecs, and plant lectins are largely unaffected by adjacent internal sialylation, and in several cases the internal sialic acids are recognized as ligands. Polyclonal IgY antibodies specific for internal sialoside epitopes were elicited in inoculated chickens.
authors.affiliation: Department of Cell and Molecular Biology, and Chemical Physiology, The Scripps Research Institute, La Jolla, CA 92037, USA.
authors.forename: Corwin M
authors.initials: CM
authors.lastname: Nycholat
authors.affiliation: Department of Cell and Molecular Biology, and Chemical Physiology, The Scripps Research Institute, La Jolla, CA 92037, USA.
authors.forename: Wenjie
authors.initials: W
authors.lastname: Peng
authors.affiliation: Department of Cell and Molecular Biology, and Chemical Physiology, The Scripps Research Institute, La Jolla, CA 92037, USA.
authors.forename: Ryan
authors.initials: R
authors.lastname: McBride
authors.affiliation: Department of Life Sciences, Imperial College London, London, SW7 2AZ, United Kingdom.
authors.forename: Aristotelis
authors.initials: A
authors.lastname: Antonopoulos
authors.affiliation: Department of Cell and Molecular Biology, and Chemical Physiology, The Scripps Research Institute, La Jolla, CA 92037, USA.
authors.forename: Robert P
authors.initials: RP
authors.lastname: de Vries
authors.affiliation: Department of Chemistry, The Scripps Research Institute, La Jolla, CA 92037, USA.
authors.forename: Zinaida
authors.initials: Z
authors.lastname: Polonskaya
authors.affiliation: Department of Chemistry, The Scripps Research Institute, La Jolla, CA 92037, USA.
authors.forename: M G
authors.initials: MG
authors.lastname: Finn
authors.affiliation: Department of Life Sciences, Imperial College London, London, SW7 2AZ, United Kingdom.
authors.forename: Anne
authors.initials: A
authors.lastname: Dell
authors.affiliation: Department of Life Sciences, Imperial College London, London, SW7 2AZ, United Kingdom.
authors.forename: Stuart M
authors.initials: SM
authors.lastname: Haslam
authors.affiliation: Department of Cell and Molecular Biology, and Chemical Physiology, The Scripps Research Institute, La Jolla, CA 92037, USA.
authors.forename: James C
authors.initials: JC
authors.lastname: Paulson
mesh_terms: D006801:Humans; D010776:Photobacterium / Q000201:enzymology*; D011134:Polysaccharides / Q000138:chemical synthesis* / Q000737:chemistry / Q000494:pharmacology; D012794:Sialic Acids / Q000737:chemistry*; D012799:Sialyltransferases / Q000737:chemistry*
chemical_list: D011134:Polysaccharides; D012794:Sialic Acids; C037199:poly-N-acetyllactosamine; D012799:Sialyltransferases