State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China.
State Key Laboratory of Phytochemistry and Plant Resources in West China, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming 650201, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Carbohydr Polym. 2020 Apr 1;233:115844. doi: 10.1016/j.carbpol.2020.115844. Epub 2020 Jan 11.
A glycosaminoglycan was isolated from the sea cucumber Holothuria coluber (HcFG). A series of oligosaccharide fragments (dp range 3-11) were prepared from its β-eliminative depolymerized product (dHcFG). Extensive NMR characterization of the oligosaccharides indicated the d-GlcA-β1,3-d-GalNAc repeating disaccharide backbone was substituted by monosaccharide branches comprising of Fuc, Fuc and Fuc, linked to O-3 of d-GlcA. For the prevailing Fuc at nonreducing end of dHcFG, the β-eliminative depolymerization process of HcFG was compared with those of the FGs from Actinopyga miliaris (AmFG, branched with Fuc) and Stichopus variegatus (SvFG, branched with Fuc). The result suggested that d-GlcA substituted with Fuc was more susceptible to depolymerization than that with Fuc. It might be due to the larger steric hindrance effects from Fuc on the esterification of GlcA. Biological assays confirmed that the minimum chain length (dp8), regardless of the Fuc branch types, was required for the potent anti-iXase and anticoagulant activities in FG fragments.
从海参 Holothuria coluber (HcFG) 中分离得到一种糖胺聚糖。从其β消除解聚产物 (dHcFG) 中制备了一系列寡糖片段 (dp 范围 3-11)。寡糖的广泛 NMR 表征表明，β-消除解聚产物的 d-GlcA-β1,3-d-GalNAc 重复二糖主链被包含 Fuc、Fuc 和 Fuc 的单糖支链取代，连接到 d-GlcA 的 O-3 上。对于 dHcFG 非还原端的主要 Fuc，将 HcFG 的β消除解聚过程与 Actinopyga miliaris (AmFG，支化为 Fuc) 和 Stichopus variegatus (SvFG，支化为 Fuc) 的 FG 进行了比较。结果表明，带有 Fuc 的 d-GlcA 比带有 Fuc 的 d-GlcA 更容易发生解聚。这可能是由于 Fuc 对 GlcA 的酯化作用产生的空间位阻效应更大。生物测定证实，无论 Fuc 支链类型如何，FG 片段中具有强抗 iXase 和抗凝血活性所需的最小链长 (dp8)。
