Biosynthesis of glycoproteins in human placenta: differential labeling of mannose and heterogeneity of oligosaccharide lipid intermediates.
Biosynthesis of glycoproteins in human placenta: differential labeling of mannose and heterogeneity of oligosaccharide lipid intermediates.
复制标题
人胎盘中糖蛋白的生物合成：甘露糖的差异标记和寡糖脂质中间体的异质性。
DOI：
10.1016/0003-9861(84)90437-5
复制
发表时间：
1984
影响因子：
3.9
通讯作者：
Bahl,OP
中科院分区：
文献类型：
--
作者：
French,WC;Henner,JA;Bahl,OP
在妊娠早期人类胎盘中研究了脂联寡糖的生物合成。用[2- 3 H]甘露糖、[1- 3 H]葡糖胺和[1- 3 H]半乳糖脉冲组织（用于[3 H]葡萄糖掺入）。脂质连接的寡糖（OSL）在DEAE-纤维素上纯化。从OSL中裂解脂质后，通过纸层析和硼酸盐高压电泳纯化寡糖。通过内切-β-N-乙酰氨基葡萄糖苷酶H和α-甘露糖苷酶的酶解以及甲基化、乙酰化和Smith降解对由此获得的组成为Glc 0 - 3 Man 9 GlcNAc 2的四种主要寡糖进行了表征。虽然相同的Glc 1 - 3 Man 9 GlcNAc 2寡糖已从其他体内系统中分离出来，但Man 9 Glc 2的存在在人胎盘中是新的。此外，Man 9 GlcNAc 2在胎盘中以可观的量存在。其次，Man 9 GlcNAc 2中的一个甘露糖比Glc 0 - 3 Man 9 GlcNAc 2寡糖中的其他甘露糖残基具有显著更高的比放射性。第三，Man 9 GlcNAc 2的差异标记和我们的脉冲追踪研究表明Man 9 GlcNAc 2不是Glc 3 Man 9 GlcNAc 2的主要前体。这些数据还表明，第九甘露糖，具有最高的放射性，可能会被纳入不同的亚细胞区室，并可能作为一个调节步骤，在生物合成的脂质连接的寡糖。提出了一个模型，概述了可能的多种途径的脂联寡糖的生物合成在人类胎盘。
The biosynthesis of lipid-linked oligosaccharides has been studied in first trimester human placentas. Tissue was pulsed with [2-3H]mannose, [1-3H]glucosamine, and [1-3H]galactose (for [3H]glucose incorporation). The lipid-linked oligosaccharides (OSL) were purified on DEAE-cellulose. After cleaving the lipid from OSL the oligosaccharides were purified by paper chromatography and borate high-voltage electrophoresis. Four major oligosaccharides with the composition Glc0–3Man9GlcNAc2thus obtained were characterized enzymatically by digestion with endo-β-N-acetylglucosaminidase H and α-mannosidase, and chemically by methylation, acetolysis, and Smith degradation. While identical Glc1–3Man9GlcNAc2oligosaccharides have been isolated from otherin vivosystems, the presence of Man9Glc2is novel for human placenta. Furthermore, Man9GlcNAc2is present in appreciable amounts in placenta. Second, one mannose in Man9GlcNAc2had a significantly higher specific radioactivity than the other mannosyl residues of the Glc0–3Man9GlcNAc2oligosaccharides. Third, the differential labeling in Man9GlcNAc2and our pulse-chase studies indicate that Man9GlcNAc2is not a major precursor of Glc3Man9GlcNAc2. The data also suggest that the ninth mannose, which has the highest radioactivity, may be incorporated in a different subcellular compartment and may serve as a regulatory step in the biosynthesis of lipid-linked oligosaccharides. A model is proposed which outlines possible multiple pathways of lipid-linked oligosaccharide biosynthesis in human placenta.