Zhang Jinhua, Xie Yongming, Hedrick Jerry L, Lebrilla Carlito B
Department of Chemistry and School of Medicine: Biological Chemistry, University of California, Davis, CA 95616, USA.
Anal Biochem. 2004 Nov 1;334(1):20-35. doi: 10.1016/j.ab.2004.07.012.
The morphological distribution of oligosaccharides is determined in the egg jelly surrounding Xenopus laevis eggs. This biological system is used to illustrate a method for readily identifying and quantifying oligosaccharides in specific tissues. The extracellular matrix surrounding X. laevis eggs consists of a vitelline envelope and a jelly coat. The jelly coat contains three morphologically distinct layers designated J1, J2, and J3 from the innermost to the outermost and is composed of 9-11 distinct glycoproteins. Each jelly layer is known to have specific functions in the fertilization of the egg. We developed a rapid method to separate and identify the oligosaccharides from X. laevis egg jelly layers. Identification was based on the retention times in high-performance liquid chromatography (porous graphitized carbon column), exact masses, and tandem mass spectrometry. Over 40 neutral and 30 sulfated oligosaccharides were observed in the three jelly layers. Neutral oligosaccharide structures from different jelly layers were both unique and overlapping, while sulfated oligosaccharides were detected only in layers J1 and J2. Neutral oligosaccharides unique to jelly layer J3 and the combined layers J1+J2 had similar core structures and similar residues. However, differences between these two sets of unique oligosaccharides were also observed and were primarily due to the branching carbohydrate moieties rather than the core structures.
在非洲爪蟾卵周围的卵胶中确定了寡糖的形态分布。这个生物系统用于说明一种在特定组织中快速鉴定和定量寡糖的方法。非洲爪蟾卵周围的细胞外基质由卵黄膜和胶膜组成。胶膜包含从最内层到最外层的三个形态上不同的层，分别称为J1、J2和J3，由9 - 11种不同的糖蛋白组成。已知每个胶膜层在卵的受精过程中具有特定功能。我们开发了一种从非洲爪蟾卵胶膜层中分离和鉴定寡糖的快速方法。鉴定基于高效液相色谱（多孔石墨化碳柱）中的保留时间、精确质量和串联质谱。在三个胶膜层中观察到了40多种中性寡糖和30多种硫酸化寡糖。来自不同胶膜层的中性寡糖结构既有独特性又有重叠性，而硫酸化寡糖仅在J1和J2层中检测到。胶膜层J3和组合层J1 + J2特有的中性寡糖具有相似的核心结构和相似的残基。然而，也观察到了这两组独特寡糖之间的差异，主要是由于分支碳水化合物部分而非核心结构。
