title: Saturation transfer difference (STD) 1H-NMR experiments and in silico docking experiments to probe the binding of N-acetylneuraminic acid and derivatives to Vibrio cholerae sialidase.
abstract: Saturation transfer difference (STD) (1)H NMR experiments were used to probe the epitope binding characteristics of the sialidase [EC 3.2.1.18] from the bacterium Vibrio cholerae, the causative agent of cholera. Binding preferences were investigated for N-acetylneuraminic acid (Neu5Ac, 1), the product of the sialidase catalytic reaction, for the known sialidase inhibitor 5-acetamido-2,6-anhydro-3,5-dideoxy-D-glycero-D-galacto-non-2-enoic acid (Neu5Ac2en, 2), and for the uronic acid-based Neu5Ac2en mimetic iso-propyl 2-acetamido-2,4-dideoxy-alpha-L-threo-hex-4-enopyranosiduronic acid (3), in which the native glycerol side-chain of Neu5Ac2en is replaced with an O-iso-propyl ether. The STD experiments provided evidence, supporting previous studies, that Neu5Ac (1) binds to the sialidase as the alpha-anomer. Docking experiments using DOCK (version 4.0.1) revealed further information regarding the binding characteristics of the enzyme active site in complex with Neu5Ac2en (2) and the Neu5Ac2en mimetic (3), indicating an expected dominant interaction of the acetamide moiety with the protein.
authors.affiliation: Institute for Glycomics, Griffith University Gold Coast Campus, Queensland, Australia.
authors.forename: Thomas
authors.initials: T
authors.lastname: Haselhorst
authors.forename: Jennifer C
authors.initials: JC
authors.lastname: Wilson
authors.forename: Robin J
authors.initials: RJ
authors.lastname: Thomson
authors.forename: Sarah
authors.initials: S
authors.lastname: McAtamney
authors.forename: John G
authors.initials: JG
authors.lastname: Menting
authors.forename: Ross L
authors.initials: RL
authors.lastname: Coppel
authors.forename: Mark
authors.initials: M
authors.lastname: von Itzstein
mesh_terms: D000081:Acetamides / Q000378:metabolism; D001426:Bacterial Proteins / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology; D001665:Binding Sites; D004791:Enzyme Inhibitors / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D057927:Hydrophobic and Hydrophilic Interactions; D015394:Molecular Structure; D019158:N-Acetylneuraminic Acid / Q000031:analogs & derivatives* / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology; D009439:Neuraminidase / Q000037:antagonists & inhibitors / Q000737:chemistry* / Q000378:metabolism; D019906:Nuclear Magnetic Resonance, Biomolecular; D011485:Protein Binding; D011487:Protein Conformation; D012996:Solutions; D013329:Structure-Activity Relationship; D014574:Uronic Acids / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D014734:Vibrio cholerae / Q000201:enzymology*
chemical_list: D000081:Acetamides; D001426:Bacterial Proteins; D004791:Enzyme Inhibitors; D012996:Solutions; D014574:Uronic Acids; C492746:isopropyl 2-acetamido-2,4-dideoxyhex-4-enopyranosiduronic acid; C036137:2-deoxy-2,3-dehydro-N-acetylneuraminic acid; D009439:Neuraminidase; D019158:N-Acetylneuraminic Acid