Glycosphingolipids fatty acids

Rhodamine 6G long-chain hydrocarbons [169] squalene, a-amyrin [170] methyl esters of fatty acids [171] glycerides [91] sterols [172, 173] isoprenoids, quinones [HI] lipoproteins [174] glycosphingolipids [175] phenolic lipids [176] phosphonolipids [177] increasing the sensitivity after exposure to iodine vapor [178,179]... 

FIGURE 9.4 TLC-blotting/SIMS of various glycosphingolipids. (A) TLC profile of the separated glycosphingolipids, (B) MS profiles obtained by TLC-blotting/SIMS (a) spectrum of sulfatide peaks at m/z 862, 876, 890, 906, and 918 are molecular ions with different fatty acid species indicated in the figure (asterisks are peaks of triethanolamine as matrix) (b) spectrum of Gb Cer peaks at m/z 1309 and 1337 are molecular ions with different fatty acid species as indicated (c) spectrum of G peaks at m/z 1151, 1235, and 1263 are molecular ions with different fatty acid species as shown. Abbreviations LCB — long chain base, FA — fatty acid, hFA — hydroxyfatty acid. Hex — hexose, HexNAc — /V-acetylhexosamine. (From Taki, T. et al.. Anal. Biochem., 225, 24—27, 1995. With permission.) Continued. 

Labyrin- thomorpba Thrausto- chytriaies 0/30 Mar. FATTY ACIDS docosahexaenoic acid. MDC. BIOGEN. glycosphingolipids Jenkins 1999 medi- um low... 

Structure of a neutral glycosphingolipid, galactocerebroside (R is a fatty acid hydrocarbon chain). 

Structural studies of glycosphingolipids involves determination of the structure of the oligosaccharide chain and of the lipid moiety. For the oligosaccharide chain, it is necessary to determine the composition, molar ratio, and sequence of the monosaccharides, their pyranose or furanose nature, and the position of glycosidic bonds and their configuration for the lipid moiety, the composition of the fatty acids and sphingosine bases must be determined. Used for these purposes are the classical, chemical methods, conventionally accepted in the chemistry of carbohydrates and lipids and based on the degradation of compounds, enzymic, and physicochemical methods, primarily mass spectrometry and n.m.r. spectroscopy. 

In contrast to the striking divergences in the carbohydrate parts, respective ceramide moieties resemble those of other cestode glycosphingolipids in so far as sphinganine (d18 0) and 4-hydroxy-sphingoid bases (tl 8 0, t20 0) as well as, in part hydroxylated, fatty acids with 16 to 28 carbon atoms, in particular C26 0 and C28 0, represent predominant ceramide constituents, which might be an indication of similar biosynthetic routes. 

Precoated silica gel plates (silica gel 60) were purchased from Scientific Products. Bio-Sil A (200 - 400 Mesh) was obtained from Bio-Rad Laboratories. Fatty acid methyl esters, sphingosine and dihydrosphingosine were products of Supelco, Inc. as were 10% DEGS-PS, 3% SP-2340 and 3% OV-17 (all on Supelcoport support). N-acetyl and N-glycolyl neuraminic acid, DEAE-Sephadex A50 and neuraminidase type IX were obtained from Sigma Company. Ganglio-side standards from human brain and neutral glycosphingolipid standards from bovine erythrocytes were prepared in this laboratory. 

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