Levery S B, Nudelman E D, Hakomori S
Biomembrane Institute, Seattle, Washington 98119.
Biochemistry. 1992 Jun 16;31(23):5335-40. doi: 10.1021/bi00138a013.
A glycosphingolipid component of human brain, having long-chain cyclic acetals, has been isolated and characterized. This compound incorporates a novel type of natural glycan modification, in which a long-chain aliphatic aldehyde is conjugated through a cyclic acetal (plasmal) linkage to the galactosyl moiety of cerebroside. In addition to components normally observed by gas chromatography-mass spectrometry (GC-MS) following methanolysis of cerebroside (fatty acid methyl esters, methyl alpha- and beta-galactosides, sphingosine), this compound produced 16:0, 18:0, and 18:1 fatty aldehydes, unequivocally identified as their enol methyl ether derivatives. Results of positive ion fast atom bombardment mass spectrometry (FAB-MS) of the native compound, and GC-MS of partially methylated hexitol acetates derived from the permethylated derivative, were consistent with structures of galactocerebroside having 3,4- and 4,6-linked cyclic plasmal substituents, as shown. [formula: see text]
一种具有长链环状缩醛的人脑海糖脂成分已被分离和表征。该化合物包含一种新型的天然聚糖修饰，其中长链脂肪醛通过环状缩醛（缩醛磷脂）键与脑苷脂的半乳糖基部分共轭。除了脑苷脂甲醇解后通过气相色谱 - 质谱法（GC-MS）通常观察到的成分（脂肪酸甲酯、α-和β-甲基半乳糖苷、鞘氨醇）外，该化合物还产生了16:0、18:0和18:1脂肪酸醛，明确鉴定为它们的烯醇甲基醚衍生物。天然化合物的正离子快原子轰击质谱（FAB-MS）结果以及衍生自全甲基化衍生物的部分甲基化己糖醇乙酸酯的GC-MS结果与具有3,4-和4,6-连接的环状缩醛磷脂取代基的半乳糖脑苷脂结构一致，如图所示。[分子式：见原文]
