Hanisch F G, Uhlenbruck G, Peter-Katalinic J, Egge H, Dabrowski U, Dabrowski J
Institute of Immunobiology, University Clinics of Cologne, FRG.
Symp Soc Exp Biol. 1989;43:155-62.
Neutral O-glycans on human skim milk mucins exhibit unique structural features, which may be summarized as follows: 1) the carbohydrate chains comprise up to 16 (or more) monosaccharide units; 2) the core structures are of the common type 2 Gal beta(1-3)[GlcNAc beta(1-6)]GalNAc; 3) the poly-N-acetyllactosamine backbones of the major glycans are unbranched; 4) the repetitive N-acetyllactosamine units of the linear species are linked by the hitherto unknown sequence GlcNAc beta(1-6)Gal rather than GlcNAc beta(1-3)Gal; 5) another major portion of mucin O-glycans represents branched isomers of the linear species containing except for their branching points at 3,6 disubstituted galactose residues the same structural elements as their unbranched counterparts; 6) fucosylation at various sites of the polyactosamine sequences yields mono-, di- and trifucosylated species; 7) fucosylation occurs predominantly at the subterminal GlcNAc and at the core-GlcNAc of the carbohydrate chain.
人脱脂乳黏蛋白上的中性O-聚糖具有独特的结构特征，可总结如下：1）碳水化合物链包含多达16个（或更多）单糖单元；2）核心结构为常见的2型Galβ(1-3)[GlcNAcβ(1-6)]GalNAc；3）主要聚糖的聚N-乙酰乳糖胺主链无分支；4）线性物种的重复N-乙酰乳糖胺单元通过迄今未知的序列GlcNAcβ(1-6)Gal连接，而非GlcNAcβ(1-3)Gal；5）黏蛋白O-聚糖的另一个主要部分代表线性物种的分支异构体，除了其在3,6-二取代半乳糖残基处的分支点外，含有与其无分支对应物相同的结构元件；6）在聚乳糖胺序列的各个位点进行岩藻糖基化产生单岩藻糖基化、双岩藻糖基化和三岩藻糖基化物种；7）岩藻糖基化主要发生在碳水化合物链的次末端GlcNAc和核心GlcNAc处。
