Structures of neutral O-linked polylactosaminoglycans on human skim milk mucins. A novel type of linearly extended poly-N-acetyllactosamine backbones with Gal beta(1-4)GlcNAc beta(1-6) repeating units.
Structures of neutral O-linked polylactosaminoglycans on human skim milk mucins. A novel type of linearly extended poly-N-acetyllactosamine backbones with Gal beta(1-4)GlcNAc beta(1-6) repeating units.
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人脱脂乳粘蛋白上的中性 O-连接聚乳糖胺聚糖的结构。
DOI：
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发表时间：
1989
影响因子：
4.8
通讯作者：
U. Dąbrowski
中科院分区：
文献类型：
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作者：
F. Hanisch;G. Uhlenbruck;J. Peter;Heinz Egge;J. Dąbrowski;U. Dąbrowski
O-连接寡糖是通过还原性β-消除从人脱脂乳粘蛋白和粘蛋白衍生的糖肽中分离出来的。释放的糖醇通过DEAE-Sephadex色谱分离，并通过伯胺键合相高效液相色谱纯化。主要中性寡糖糖醇的结构可通过快速原子轰击和电子轰击质谱法，结合甲基化分析、500-MHz 1H核磁共振光谱法和内切-β-半乳糖苷酶（来自脆弱拟杆菌，EC 3.2.1.103）消化来确定（其中n = 0-3）：（公式;脱脂乳粘蛋白上的主要O-糖苷键连接寡糖是Gal β（1-3）[GlcNAc β（1-6）] GalNAc核心类型2，并显示聚N-乙酰基乳糖胺类型的线性延伸主链，其包含多达至少四个重复单元，其通过迄今未知的序列GlcNAc-β（1-6）Gal而不是GlcNAc β（1-3）Gal连接。相当大一部分中性糖醇由直链种类的支链异构体代表，其特征在于它们的3，6-二取代半乳糖含量和它们对内切-β-半乳糖苷酶消化的部分抗性。
O-Linked oligosaccharides were isolated from human skim milk mucins and from mucin-derived glycopeptides by reductive beta-elimination. The released alditols were fractionated by DEAE-Sephadex chromatography and purified by high performance liquid chromatography on primary amine bonded phase. The structures of the major neutral oligosaccharide alditols could be established by fast atom bombardment and electron impact mass spectrometry, combined with methylation analysis, 500-MHz 1H nuclear magnetic resonance spectroscopy, and endo-beta-galactosidase (from Bacteroides fragilis, EC 3.2.1.103) digestion (where n = 0-3): (formula; see text) Major O-glycosidically linked oligosaccharides on skim milk mucins are of the Gal beta(1-3)[GlcNAc beta(1-6)] GalNAc core type 2 and exhibit linearly extended backbone chains of the poly N-acetyllactosamine type comprizing up to at least four repeating units, which are linked by the hitherto unknown sequence GlcNAc-beta(1-6) Gal rather than GlcNAc beta(1-3)Gal. A considerable portion of neutral alditols is represented by branched isomers of the linear species, which are distinguished by their content of 3,6-disubstituted galactose and their partial resistance to endo-beta-galactosidase digestion.