title: Efficient chemoenzymatic synthesis of O-linked sialyl oligosaccharides.
abstract: The tumor associated Tn (GalNAcalpha(1-1)-Thr/Ser)- and T (Galbeta(1-3)-GalNAcalpha(1-1)Thr/Ser)-antigens and their sialylated derivatives are present on the surface of many cancer cells. Preparative synthesis of these sialylated T- and Tn-structures has been achieved mainly from a chemical synthetic approach due to the lack of the required glycosyltransferases. We demonstrate a flexible and efficient chemoenzymatic approach for using recombinant sialyltransferases including a chicken GalNAcalpha2,6-sialyltransferase (chST6GalNAc I) and a porcine Galbeta(1-3)GalNAcalpha-2,3-sialyltransferase (pST3Gal I). Using these enzymes, the common O-linked sialosides Neu5Acalpha(2-6)GalNAcalpha(1-1)Thr, Galbeta(1-3)[Neu5Acalpha(2-6)]GalNAcalpha(1-1)Thr, Neu5Acalpha(2-3)Galbeta(1-3)GalNAcalpha(1-1)Thr, and Neu5Acalpha(2-3)Galbeta(1-3)[Neu5Acalpha(2-6)]GalNAcalpha(1-1)Thr were readily prepared at preparative scale. The chST6GalNAc I was found to require at least one amino acid (Thr/Ser) for optimal activity, and is thus an ideal catalyst for synthesis of synthetic glycopeptides and glycoconjugates with O-linked glycans.
authors: The Scripps Research Institute, Department of Molecular Biology, MEM-L71, 10550 North Torrey Pines Road, La Jolla, California 92037, USA.
authors: Ola
authors: O
authors: Blixt
authors: Kirk
authors: K
authors: Allin
authors: Laura
authors: L
authors: Pereira
authors: Arun
authors: A
authors: Datta
authors: James C
authors: JC
authors: Paulson
mesh_terms: D000818:Animals; D015295:Antigens, Tumor-Associated, Carbohydrate / Q000096:biosynthesis / Q000737:chemistry*; D002240:Carbohydrate Sequence; D002645:Chickens; D008969:Molecular Sequence Data; D009077:Mucins / Q000096:biosynthesis / Q000138:chemical synthesis* / Q000737:chemistry; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics / Q000378:metabolism; D012799:Sialyltransferases / Q000096:biosynthesis / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D013379:Substrate Specificity; D013552:Swine; D000094802:beta-D-Galactoside alpha 2-6-Sialyltransferase; D000094663:beta-Galactoside alpha-2,3-Sialyltransferase
chemical_list: D015295:Antigens, Tumor-Associated, Carbohydrate; D009077:Mucins; D011994:Recombinant Proteins; C087769:sialosyl-T antigen; C055491:sialosyl-Tn antigen; D012799:Sialyltransferases; D000094802:beta-D-Galactoside alpha 2-6-Sialyltransferase; D000094663:beta-Galactoside alpha-2,3-Sialyltransferase