title: Design and facile synthesis of neoglycolipids as lactosylceramide mimetics and their transformation into glycoliposomes.
abstract: Neoglycolipids composed of disaccharide glycoside and phospholipid were designed and prepared as mimetics of lactosylceramide. The lactosyl- and N-acetyllactosaminyl-phospholipids (Lac-DPPA and LacNAc-DPPA) were enzymatically synthesized from lactose and LacNAc respectively by cellulase-mediated condensation with 1,6-hexanediol, followed by conjugation of the resulting glycosides and dipalmitoylphosphatidyl choline (DPPC) mediated by Streptomyces phospholipase D. Alternatively, allyl beta-lactoside was ozonolyzed to give an aldehyde, which was condensed with dipalmytoyl phosphatidyl ethanolamine to afford a second type of glycolipid (Lac-DPPE). NMR spectroscopy indicated that the neoglycolipids behave differently in different solvent systems. X-ray diffraction clearly showed that multilamellar vesicles (MLVs) of Lac-DPPE and Lac-DPPA-MLV are in the bilayer gel phase at 20 degrees C, whereas those of Lac-DPPE-MLV were in the lamellar liquid-crystalline phase at 50 degrees C. Differential scanning calorimetry showed that Lac-DPPE-MLV had complex thermotropic behavior depending on the incubation conditions. After a long incubation at 10 degrees C, endothermic transitions are observed at 39.6, 42.3 degrees C, and 42.9 degrees C. These neoglycolipids have the ability to trap calcein, a chelating derivative of fluorescein, in MLVs and showed specific binding to lectin in plate assays using fluorescently labeled compounds.
authors.affiliation: Department of Applied Biological Chemistry, Faculty of Agriculture, Shizuoka University, Shizuoka, Japan.
authors.forename: Yoichiro
authors.initials: Y
authors.lastname: Harada
authors.forename: Takeomi
authors.initials: T
authors.lastname: Murata
authors.forename: Kazuhide
authors.initials: K
authors.lastname: Totani
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Kajimoto
authors.forename: Shah Md
authors.initials: SM
authors.lastname: Masum
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Tamba
authors.forename: Masahito
authors.initials: M
authors.lastname: Yamazaki
authors.forename: Taichi
authors.initials: T
authors.lastname: Usui
mesh_terms: D002152:Calorimetry, Differential Scanning; D006017:Glycolipids / Q000138:chemical synthesis* / Q000737:chemistry; D007790:Lactosylceramides / Q000737:chemistry; D037102:Lectins / Q000737:chemistry; D008081:Liposomes / Q000737:chemistry*; D015394:Molecular Structure; D014961:X-Ray Diffraction
chemical_list: D006017:Glycolipids; D007790:Lactosylceramides; D037102:Lectins; D008081:Liposomes