Amongst the earliest deuterostomes, the echinoderms are an evolutionary important group of ancient marine animals. Within this phylum, the holothuroids (sea cucumbers) are known to produce a wide range of glycoconjugate biopolymers with apparent benefits to health; therefore, they are of economic and culinary interest throughout the world. Other than their highly modified glycosaminoglycans (e.g. fucosylated chondroitin sulphate and fucoidan), nothing is known about their protein-linked glycosylation. Here, we used multi-step N-glycan fractionation to efficiently separate the anionic and neutral N-glycans before analyzing the N-glycans of the black sea cucumber (Holothuria atra) by MS in combination with enzymatic and chemical treatments. These analyses showed the presence of various fucosylated, phosphorylated, sialylated and multiply sulphated moieties as modifications of oligomannosidic, hybrid and complex-type N-glycans. The high degree of sulphation and fucosylation parallels the modifications previously observed on holothuroid glycosaminoglycans. Compatible with its phylogenetic position, H. atra not only expresses vertebrate motifs such as sulpho- and sialyl-Lewis A epitopes, but displays a high degree of anionic substitution of its glycans as observed in other marine invertebrates. Thus, as for other echinoderms, the phylum- and order-specific aspects of this species' N-glycosylation reveal both invertebrate- and vertebrate-like features.

中文翻译：

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棘皮动物 Holothuria atra 中的硫酸化和唾液酸化 N-聚糖反映了其海洋栖息地和系统发育。

在最早的氘核动物中，棘皮动物是古代海洋动物的重要进化群体。在这个门中，众所周知，海参（海参）可以产生范围广泛的糖缀合物生物聚合物，对健康有明显的好处。因此，它们在全世界都具有经济和烹饪价值。除了高度修饰的糖胺聚糖（例如岩藻糖基化硫酸软骨素和岩藻依聚糖）外，对于它们的蛋白连接糖基化一无所知。在这里，我们使用多步 N-聚糖分馏来有效分离阴离子和中性 N-聚糖，然后通过 MS 结合酶促和化学处理分析黑海参 (Holothuria atra) 的 N-聚糖。这些分析表明存在各种岩藻糖基化、磷酸化、唾液酸化和多硫酸化部分作为寡甘露糖苷、杂合和复合型 N-聚糖的修饰。高度硫酸化和岩藻糖基化与之前在海参糖胺聚糖上观察到的修饰相似。与其系统发育位置相容，H. atra 不仅表达脊椎动物基序，如磺基和唾液酸刘易斯 A 表位，而且在其他海洋无脊椎动物中观察到其聚糖的高度阴离子取代。因此，对于其他棘皮动物，该物种的 N-糖基化的门和目特定方面揭示了无脊椎动物和脊椎动物样特征。与其系统发育位置相容，H. atra 不仅表达脊椎动物基序，如磺基和唾液酸刘易斯 A 表位，而且在其他海洋无脊椎动物中观察到其聚糖的高度阴离子取代。因此，对于其他棘皮动物，该物种的 N-糖基化的门和目特定方面揭示了无脊椎动物和脊椎动物样特征。与其系统发育位置相容，H. atra 不仅表达脊椎动物基序，如磺基和唾液酸刘易斯 A 表位，而且在其他海洋无脊椎动物中观察到其聚糖的高度阴离子取代。因此，对于其他棘皮动物，该物种的 N-糖基化的门和目特定方面揭示了无脊椎动物和脊椎动物样特征。