title: Synthesis of E. faecium wall teichoic acid fragments.
abstract: The first synthesis of different Enterococcus faecium wall teichoic acid (WTA) fragments is presented. The structure of these major cell wall components was elucidated recently and it was shown that these glycerolphosphate (GroP) based polymers are built up from -6-(GalNAc-α(1-3)-GalNAc-β(1-2)-GroP)- repeating units. We assembled WTA fragments up to three repeating units in length, in two series that differ in the stereochemistry of the glycerolphosphate moiety. The key GalNAc-GalNAc-GroP synthons, required for the synthesis, were generated from galactosazide building blocks that were employed in highly stereoselective glycosylation reactions to furnish both the α- and β-configured linkages. By comparing the NMR spectra of the synthesized fragments with the isolated material it appears that the hereto undefined stereochemistry of the glycerol phosphate moiety is sn-glycerol-3-phosphate. The generated fragments will be valuable tools to study their immunological activity at the molecular level.
authors.affiliation: Leiden Institute of Chemistry, Leiden University, PO Box 9502, 2300 RA Leiden, The Netherlands.
authors.forename: Daan
authors.initials: D
authors.lastname: van der Es
authors.affiliation: Leiden Institute of Chemistry, Leiden University, PO Box 9502, 2300 RA Leiden, The Netherlands.
authors.forename: Nadia A
authors.initials: NA
authors.lastname: Groenia
authors.affiliation: Division of Pediatric Infectious Diseases, Dr. von Hauner Children's Hospital, Ludwig-Maximilians-University, Munich, Germany.
authors.forename: Diana
authors.initials: D
authors.lastname: Laverde
authors.affiliation: Leiden Institute of Chemistry, Leiden University, PO Box 9502, 2300 RA Leiden, The Netherlands.
authors.forename: Herman S
authors.initials: HS
authors.lastname: Overkleeft
authors.affiliation: Division of Pediatric Infectious Diseases, Dr. von Hauner Children's Hospital, Ludwig-Maximilians-University, Munich, Germany.
authors.forename: Johannes
authors.initials: J
authors.lastname: Huebner
authors.affiliation: Leiden Institute of Chemistry, Leiden University, PO Box 9502, 2300 RA Leiden, The Netherlands. Electronic address: marel_g@chem.leidenuniv.nl.
authors.forename: Gijsbert A
authors.initials: GA
authors.lastname: van der Marel
authors.affiliation: Leiden Institute of Chemistry, Leiden University, PO Box 9502, 2300 RA Leiden, The Netherlands. Electronic address: jcodee@chem.leidenuniv.nl.
authors.forename: Jeroen D C
authors.initials: JDC
authors.lastname: Codée
mesh_terms: D002240:Carbohydrate Sequence; D002473:Cell Wall / Q000737:chemistry*; D016984:Enterococcus faecium / Q000737:chemistry*; D013237:Stereoisomerism; D013682:Teichoic Acids / Q000138:chemical synthesis*
chemical_list: D013682:Teichoic Acids
keywords: Carbohydrate; E. faecium; Glycosylation; Phosphoramidite; Wall teichoic acid