Gb₃ glycosphingolipids are the specific receptors for bacterial Shiga toxin. Whereas the trisaccharidic head group of Gb₃ defines the specificity of Shiga toxin binding, the lipophilic part composed of sphingosine and different fatty acids is suggested to determine its localization within membranes impacting membrane organisation and protein binding eventually leading to protein internalisation. While most studies use Gb₃ extracts, chemical synthesis provides a unique tool to access different tailor-made Gb₃ glycosphingolipids. In this review, strategies to synthesize these complex glycosphingolipids are presented. Special emphasis is put on the preparation of Gb₃ molecules differing only in their fatty acid part (saturated, unsaturated, α-hydroxylated and both, unsaturated and α-hydroxylated). With these molecules in hand, it became possible to investigate the phase behaviour of liquid ordered/liquid disordered supported membranes doped with the Gb₃ species by means of fluorescence and atomic force microscopy. The results clearly highlight the influence of the different fatty acids of the Gb₃ sphingolipids on the phase behaviour and the binding properties of Shiga toxin B subunits, even though the membranes were only doped with 5 mol% of the receptor lipid. To obtain fluorescent Gb₃ derivatives, either fatty acid labelled Gb₃ molecules or head group labelled ones were synthesized. These molecules enabled us to address the question, where the Gb₃ sphingolipids are localized prior protein binding by means of fluorescence microscopy on giant unilamellar vesicles. The results again demonstrate that the fatty acid of Gb₃ plays a pivotal role for the overall membrane organisation.

Gb ₃鞘糖脂是细菌志贺毒素的特异性受体。虽然 Gb ₃的三糖头基定义了志贺毒素结合的特异性，但由鞘氨醇和不同脂肪酸组成的亲脂部分被建议确定其在膜内的定位，影响膜组织和蛋白质结合，最终导致蛋白质内化。虽然大多数研究使用 Gb ₃提取物，但化学合成提供了一种独特的工具来获取不同的定制 Gb ₃鞘糖脂。在这篇综述中，提出了合成这些复杂鞘糖脂的策略。特别强调仅在脂肪酸部分不同的Gb ₃分子的制备（饱和、不饱和、α-羟基化以及两者，不饱和和α-羟基化）。有了这些分子，就可以通过荧光和原子力显微镜研究掺杂有 Gb ₃物质的液体有序/液体无序支撑膜的相行为。结果清楚地突出了 Gb ₃鞘脂的不同脂肪酸对志贺毒素 B 亚基的相行为和结合特性的影响，即使膜仅掺杂 5 mol% 的受体脂质。为了获得荧光Gb ₃衍生物，合成了脂肪酸标记的Gb ₃分子或头基标记的分子。这些分子使我们能够解决这个问题，其中 Gb ₃鞘脂通过荧光显微镜在巨大的单层囊泡上定位于蛋白质结合之前。 结果再次证明 Gb ₃的脂肪酸对于整个膜组织起着关键作用。