title: Characterization of ganglioside GM4 lactones isolated from the whale brain.
abstract: Two novel ganglioside lactones were isolated from the brain of Bryde's whale (Balaenoptera edeni) and characterized. These gangliosides migrated above GM4 and were designated M4-1 and M4-2 in the order of location from the bottom of the TLC plate. These gangliosides were converted to GM4 by mild alkali treatment. Although M4-1 and M4-2 contained 1 mol each of N-acetylneuraminic acid and galactose, they behaved as neutral lipids on ion-exchange chromatography. Inner ester linkages were found in these gangliosides by secondary ion mass spectrometry and infrared spectroscopy. Two-dimensional J-correlated proton NMR spectra revealed that an inner ester linkage was formed in M4-1 between the sialic acid carboxyl group and the C-4 hydroxyl group of the galactosyl residue and another inner ester linkage was formed in M4-2 between the sialic acid carboxyl group and the C-2 hydroxyl group of galactose.
authors.affiliation: Department of Chemistry, Kitasato University, Kanagawa.
authors.forename: T
authors.initials: T
authors.lastname: Terabayashi
authors.forename: T
authors.initials: T
authors.lastname: Ogawa
authors.forename: Y
authors.initials: Y
authors.lastname: Kawanishi
mesh_terms: D000818:Animals; D001923:Brain Chemistry; D002591:Cetacea / Q000378:metabolism*; D055598:Chemical Phenomena; D002621:Chemistry; D002855:Chromatography, Thin Layer; D005732:Gangliosides / Q000302:isolation & purification* / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D014907:Whales / Q000378:metabolism*
chemical_list: D005732:Gangliosides; C065512:ganglioside GM4-2; C065511:ganglioside GM4-1