Mauri Laura, Valsecchi Manuela, Casellato Riccardo, Li Su-Chen, Li Yu-Teh, Sonnino Sandro
Department of Medical Chemistry, Biochemistry and Biotechnology, Center of Excellence on Neurodegenerative Diseases, University of Milan, Via Fratelli Cervi 93, 20090 Segrate, Italy.
J Chromatogr B Analyt Technol Biomed Life Sci. 2003 Oct 25;796(1):1-10. doi: 10.1016/s1570-0232(03)00598-1.
GM2 ganglioside, beta-GalNAc-(1-4)-[alpha-Neu5Ac-(2-3)-]beta-Gal-(1-4)-beta-Glc-(1-1)-Cer, is the main ganglioside in the brain of Tay-Sachs patients. In this work, GM2 ganglioside was extracted from a Variant B Tay-Sachs human brain, purified to homogeneity of the oligosaccharide moiety by silica gel chromatography. It was further fractionated for the first time into the molecular species differing in the ceramide structures by reverse-phase flash chromatography. The GM2 ganglioside species were characterized by gas-chromatography, nuclear magnetic resonance spectroscopy, and mass spectrometry. The major GM2 species contained the ceramides with d18:1-18:0 (40.5% of the total GM2 species), d20:1-18:0 (31%) and d18:1-20:0 (12%). We also found minor GM2 species with the ceramides with d18:1-24:1 (4%), d18:1-22:0 (2%) and d18:2-24:1 (1%), which have not been reported previously.
GM2神经节苷脂,即β - N - 乙酰半乳糖胺 -(1→4)-[α - N - 乙酰神经氨酸 -(2→3)-]β - 半乳糖 -(1→4)-β - 葡萄糖 -(1→1)- 神经酰胺,是患有泰 - 萨克斯病患者大脑中的主要神经节苷脂。在这项研究中,GM2神经节苷脂从一名B型变异型泰 - 萨克斯病患者的大脑中提取,通过硅胶柱色谱法将其寡糖部分纯化至同质。首次通过反相快速色谱法将其进一步分离为神经酰胺结构不同的分子种类。GM2神经节苷脂种类通过气相色谱法、核磁共振光谱法和质谱法进行表征。主要的GM2种类包含神经酰胺d18:1 - 18:0(占总GM2种类的40.5%)、d20:1 - 18:0(31%)和d18:1 - 20:0(12%)。我们还发现了含有神经酰胺d18:1 - 24:1(4%)、d18:1 - 22:0(2%)和d18:2 - 24:1(1%)的次要GM2种类,这些种类此前尚未见报道。