Synthesis of a B-Antigen Hexasaccharide, a B-Lewis b Heptasaccharide and Glycoconjugates Thereof to Investigate Binding Properties of Helicobacter pyloriShow others and affiliations
2023 (English)In: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765, Vol. 29, no 16Article in journal (Refereed) Published
Abstract [en]
Infecting the stomach of almost 50 % of people, Helicobacter pylori is a causative agent of gastritis, peptic ulcers and stomach cancers. Interactions between bacterial membrane-bound lectin, Blood group Antigen Binding Adhesin (BabA), and human blood group antigens are key in the initiation of infection. Herein, the synthesis of a B-antigen hexasaccharide (B6) and a B-Lewis b heptasaccharide (BLeb7) and Bovine Serum Albumin glycoconjugates thereof is reported to assess the binding properties and preferences of BabA from different strains. From a previously reported trisaccharide acceptor a versatile key Lacto-N-tetraose tetrasaccharide intermediate was synthesized, which allowed us to explore various routes to the final targets, either via initial introduction of fucosyl residues followed by introduction of the B-determinant or vice versa. The first approach proved unsuccessful, whereas the second afforded the target structures in good yields. Protein conjugation using isothiocyanate methodology allowed us to reach high glycan loadings (up to 23 per protein) to mimic multivalent displays encountered in Nature. Protein glycoconjugate inhibition binding studies were performed with H. pylori strains displaying high or low affinity for Lewis b hexasaccharide structures showing that the binding to the high affinity strain was reduced due to the presence of the B-determinant in the Bleb7-conjugates and further reduced by the absence of the Lewis fucose residue in the B6-conjugate.
Place, publisher, year, edition, pages
Wiley , 2023. Vol. 29, no 16
Keywords [en]
B-Lewis b, B antigen, glycoconjugate, synthesis, thioglycoside
National Category
Organic Chemistry
Identifiers
URN: urn:nbn:se:kth:diva-328057DOI: 10.1002/chem.202203672ISI: 000932377100001PubMedID: 36562295Scopus ID: 2-s2.0-85147992982OAI: oai:DiVA.org:kth-328057DiVA, id: diva2:1761870
Note
QC 20230602
2023-06-022023-06-022023-06-02Bibliographically approved