Uhrig M L, Couto A S, Colli W, de Lederkremer R M
Departamento de Química Orgánica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Argentina.
Biochim Biophys Acta. 1996 May 20;1300(3):233-9. doi: 10.1016/0005-2760(96)00021-5.
In vivo labeling experiments with [3H]palmitic acid, [3H]inositol, and [3H]glucose allowed the identification of two main classes of inositolphospholipids (IPLs) from the trypomastigote stage of Trypanosoma cruzi. Purification of these compounds was achieved by ion-exchange chromatography, high performance liquid chromatography and thin layer chromatography. Specific phosphatidyl-inositol phospholipase C digestion, dephosphorylation and acid methanolysis showed a ceramide structure for the lower migrating IPL1. Palmitoyldihydrosphingosine and palmitoylsphingosine were detected by reverse-phase thin-layer chromatography. On the other hand, IPL2 showed to be a mixture of diacylglycero- and alkylacylglycero-phospholipids in a 1:1 ratio. After PI-PLC digestion, the lipids were separated by preparative TLC and individually analysed. The diacylglycerol contained mainly C18:0 fatty acid together with a low amount of C16:0. Hexadecylglycerol esterified with the C18:0 fatty acid was the only alkylacylglycerol detected. The C18:2 and C18:1 fatty acids, preponderant in the PI molecules of epimastigote forms, were not detected in trypomastigote forms. This is the first report on inositol phospholipids, putative precursors of lipid anchors in the infective stage of T. cruzi.
利用[3H]棕榈酸、[3H]肌醇和[3H]葡萄糖进行的体内标记实验，使得从克氏锥虫的锥鞭毛体阶段鉴定出了两类主要的肌醇磷脂（IPL）。通过离子交换色谱法、高效液相色谱法和薄层色谱法实现了这些化合物的纯化。特异性磷脂酰肌醇磷脂酶C消化、去磷酸化和酸性甲醇解显示，迁移较慢的IPL1具有神经酰胺结构。通过反相薄层色谱法检测到了棕榈酰二氢鞘氨醇和棕榈酰鞘氨醇。另一方面，IPL2显示为二酰基甘油和烷基酰基甘油磷脂的1:1混合物。经磷脂酰肌醇磷脂酶C消化后，通过制备型薄层色谱法分离脂质并进行单独分析。二酰基甘油主要含有C18:0脂肪酸以及少量的C16:0。唯一检测到的烷基酰基甘油是与C18:0脂肪酸酯化的十六烷基甘油。在锥鞭毛体形式中未检测到在无鞭毛体形式的磷脂酰肌醇分子中占优势的C18:2和C18:1脂肪酸。这是关于克氏锥虫感染阶段脂质锚定的推定前体——肌醇磷脂的首次报道。
