tetano
Editor, Senior Moderator
J Am Chem Soc. 2013 Nov 20. [Epub ahead of print]
Synthesis of biologically active N- and O-linked glycans with multi-sialylated poly-N-acetyllactosamine extensions using P. damsela α2-6 sialyltransferase.
Nycholat CM, Peng W, McBride R, Antonopoulos A, de Vries RP, Polonskaya Z, Finn MG, Dell A, Haslam SM, Paulson JC.
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 non-reducing 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 ap-proach for the synthesis of a library of N- and O-linked gly-cans with multi-sialylated poly-LacNAc extensions, including naturally occurring multi-sialylated 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 con-firmed by MS/MS analysis. Using a glycan microarray dis-playing 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 sia-loside epitopes were elicited in inoculated chickens.
PMID:
24256304
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/24256304
Synthesis of biologically active N- and O-linked glycans with multi-sialylated poly-N-acetyllactosamine extensions using P. damsela α2-6 sialyltransferase.
Nycholat CM, Peng W, McBride R, Antonopoulos A, de Vries RP, Polonskaya Z, Finn MG, Dell A, Haslam SM, Paulson JC.
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 non-reducing 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 ap-proach for the synthesis of a library of N- and O-linked gly-cans with multi-sialylated poly-LacNAc extensions, including naturally occurring multi-sialylated 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 con-firmed by MS/MS analysis. Using a glycan microarray dis-playing 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 sia-loside epitopes were elicited in inoculated chickens.
PMID:
24256304
[PubMed - as supplied by publisher]
http://www.ncbi.nlm.nih.gov/pubmed/24256304