Novel structural features of the immunocompetent ceramide phospho-inositol glycan core from Trichomonas vaginalis.
Novel structural features of the immunocompetent ceramide phospho-inositol glycan core from Trichomonas vaginalis.
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DOI：
10.1016/j.carres.2015.11.001
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发表时间：
2016-01
影响因子：
3.1
通讯作者：
Singh BN
中科院分区：
文献类型：
--
作者：
Heiss C;Wang Z;Black I;Azadi P;Fichorova RN;Singh BN
阴道毛滴虫脂磷酸聚糖的神经酰胺磷酸肌醇聚糖核心 (CPI-GC) 是这种常见泌尿生殖寄生虫的主要毒力因子。虽然其碳水化合物成分之前已有报道，但其结构仍然很大程度上未知。我们通过亚硝酸脱氨和氢氟酸处理分离了 CPI-GC 的聚糖部分，并通过甲基化分析和 1- 和 2-D NMR 研究了它们的结构。我们发现半乳糖的α-端基异构体是CPI-GC的主要成分。 β-端基异构体仅存在于 CPI-GC 侧链的非还原端。此外，数据表明，鼠李聚糖主链比之前想象的更复杂，并且还原端的肌醇残基与 4-连接的 α-葡萄糖醛酸 (GlcA) 残基相连。这似乎是这种 GPI 锚定型分子最引人注目和新颖的特征。
The ceramide phosphoinositol glycan core (CPI-GC) of the lipophosphoglycan of Trichomonas vaginalis is a major virulent factor of this common genitourinary parasite. While its carbohydrate composition has been reported before, its structure has remained largely unknown. We isolated the glycan portions of CPI-GC by nitrous acid deamination and hydrofluoric acid treatment and investigated their structures by methylation analysis and 1- and 2-D NMR. We found that the α-anomer of galactose is a major constituent of CPI-GC. The β-anomer was found exclusively at the non-reducing end of CPI-GC side chains. Furthermore the data showed that the rhamnan backbone is more complex than previously thought and that the inositol residue at the reducing end is linked to a 4-linked α-glucuronic acid (GlcA) residue. This appears to be the most striking and novel feature of this GPI-anchor type molecule.