title: Sialyltransferases with enhanced legionaminic acid transferase activity for the preparation of analogs of sialoglycoconjugates.
abstract: Legionaminic acids (Leg) are bacterial analogs of neuraminic acid, with the same stereochemistry but different substituents at C5, C7 and C9. Hence they may be incorporated into useful analogs of sialoglycoconjugates, and we previously reported two sialyltransferases that could utilize cytidine monophosphate (CMP)-Leg5Ac7Ac for preparation of Leg glycoconjugates, which were resistant to sialidases [Watson DC, Leclerc S, Wakarchuk WW, Young NM. 2011. Enzymatic synthesis and properties of glycoconjugates with legionaminic acid as a replacement for neuraminic acid. Glycobiology. 21:99-108.]. These were the porcine ST3Gal1 and Pasteurella multocida sialyltransferases. We now report two additional sialyltransferases with superior Leg-transferase properties to the previous two. These are (i) a truncated form of a Photobacterium α2,6-sialyltransferase with an Ala-Met mutation in its active site, and (ii) an α2,3-sialyltransferase from Neisseria meningitidis MC58 with a higher transferase activity than the P. multocida enzyme, with either CMP-Neu5Ac or CMP-Leg5Ac7Ac as the donor. These enzymes will enable the production of useful Leg5Ac7Ac glycoconjugate derivatives with either α2,6 or α2,3 linkages and unique biological properties.
authors.affiliation: Human Health Therapeutics, National Research Council Canada, 100 Sussex Drive, Ottawa, ON, Canada K1A 0R6.
authors.forename: David C
authors.initials: DC
authors.lastname: Watson
authors.affiliation: Department of Chemistry and Biology, Ryerson University, 350 Victoria St., Toronto, Ontario Canada M5B 2K3.
authors.forename: Warren W
authors.initials: WW
authors.lastname: Wakarchuk
authors.affiliation: Human Health Therapeutics, National Research Council Canada, 100 Sussex Drive, Ottawa, ON, Canada K1A 0R6.
authors.forename: Sonia
authors.initials: S
authors.lastname: Leclerc
authors.affiliation: Human Health Therapeutics, National Research Council Canada, 100 Sussex Drive, Ottawa, ON, Canada K1A 0R6.
authors.forename: Melissa J
authors.initials: MJ
authors.lastname: Schur
authors.affiliation: Human Health Therapeutics, National Research Council Canada, 100 Sussex Drive, Ottawa, ON, Canada K1A 0R6.
authors.forename: Ian C
authors.initials: IC
authors.lastname: Schoenhofen
authors.affiliation: Human Health Therapeutics, National Research Council Canada, 100 Sussex Drive, Ottawa, ON, Canada K1A 0R6.
authors.forename: N Martin
authors.initials: NM
authors.lastname: Young
authors.affiliation: Human Health Therapeutics, National Research Council Canada, 100 Sussex Drive, Ottawa, ON, Canada K1A 0R6 michel.gilbert@nrc-cnrc.gc.ca.
authors.forename: Michel
authors.initials: M
authors.lastname: Gilbert
mesh_terms: D000818:Animals; D002236:Carbohydrate Conformation; D006001:Glycoconjugates / Q000737:chemistry / Q000378:metabolism*; D008958:Models, Molecular; D009154:Mutation; D019158:N-Acetylneuraminic Acid / Q000378:metabolism*; D016979:Pasteurella multocida / Q000201:enzymology; D010776:Photobacterium / Q000201:enzymology; D012794:Sialic Acids / Q000378:metabolism*; D012799:Sialyltransferases / Q000378:metabolism*; D013552:Swine
chemical_list: C110570:5,7-diacetamido-8-O-acetyl-3,5,7,9-tetradeoxy-glycero-talo-nonulosonic acid; D006001:Glycoconjugates; D012794:Sialic Acids; D012799:Sialyltransferases; D019158:N-Acetylneuraminic Acid
keywords: Neisseria gonorrhoeae; Neisseria meningitidis; Pasteurella multocida; Photobacterium; legionaminic acid; sialyltransferase