title: A beta-1,4-galactosyltransferase from Helicobacter pylori is an efficient and versatile biocatalyst displaying a novel activity for thioglycoside synthesis.
abstract: Helicobacter pylori is a highly persistent and common pathogen in humans. It is the causative agent of chronic gastritis and its further stages. HP0826 is the beta-1,4-galactosyltransferase involved in the biosynthesis of the LPS O-chain backbone of H. pylori. Though it was first cloned nearly a decade ago, there are surprisingly limited data about the characteristics of HP0826, especially given its prominent role in H. pylori pathogenicity. We here demonstrate that HP0826 is a highly efficient and promiscuous biocatalyst. We have exploited two novel enzymatic activities for the quantitative synthesis of the thiodisaccharide Gal-beta-S-1,4-GlcNAc-pNP as well as Gal-beta-1,4-Man-pNP. We further show that Neisseria meningitidis beta-1,4-galactosyltransferases LgtB can be used as an equally efficient catalyst in the latter reaction. Thiodisaccharides have been extensively used in structural biology but can also have therapeutic uses. The Gal-beta-1,4-Man linkage is found in the Leishmania species LPG backbone disaccharide repeats and cap, which have been associated with vector binding in Leishmaniasis.
authors.affiliation: Institute for Biological Sciences, National Research Council Canada, 100 Sussex Drive, Ottawa, ON K1A0R6, Canada.
authors.forename: Darius-Jean
authors.initials: DJ
authors.lastname: Namdjou
authors.forename: Hong-Ming
authors.initials: HM
authors.lastname: Chen
authors.forename: Evguenii
authors.initials: E
authors.lastname: Vinogradov
authors.forename: Denis
authors.initials: D
authors.lastname: Brochu
authors.forename: Stephen G
authors.initials: SG
authors.lastname: Withers
authors.forename: Warren W
authors.initials: WW
authors.lastname: Wakarchuk
mesh_terms: D001426:Bacterial Proteins / Q000302:isolation & purification / Q000378:metabolism; D002384:Catalysis; D004187:Disaccharides / Q000138:chemical synthesis / Q000737:chemistry; D004926:Escherichia coli / Q000201:enzymology; D029968:Escherichia coli Proteins / Q000302:isolation & purification / Q000378:metabolism; D016480:Helicobacter pylori / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008958:Models, Molecular; D009237:N-Acetyllactosamine Synthase / Q000302:isolation & purification / Q000378:metabolism*; D013865:Thioglycosides / Q000096:biosynthesis* / Q000737:chemistry
chemical_list: D001426:Bacterial Proteins; D004187:Disaccharides; D029968:Escherichia coli Proteins; D013865:Thioglycosides; D009237:N-Acetyllactosamine Synthase