Pharmaceutical Institute, Department of Pharmaceutical Biology, Christian-Albrechts-University of Kiel, Gutenbergstr. 76, 24118 Kiel, Germany.
Carbohydr Polym. 2017 Sep 15;172:342-351. doi: 10.1016/j.carbpol.2017.05.031. Epub 2017 May 12.
Today, understanding of cell wall evolution is incomplete due to limited knowledge of cell wall structure of non-flowering plants. Besides polysaccharides, proteoglycans like arabinogalactan-proteins are important constituents of the cell wall of most if not all seed plants. This article provides the first detailed characterization of AGPs from a lycophyte and different ferns, which are the closest living relatives to seed plants. The amount of protein in fern AGPs (6-12%) was in a range comparable to most seed plant AGPs. However, it was higher for Lycopodium AGP (17%). The carbohydrate moieties of investigated AGPs showed typical features known for type-II arabinogalactans from seed plants and showed cross-reaction with polyclonal antibodies raised against Echinacea AGP. On the other hand, unusual structural components like high quantities of pyranosidic arabinose residues for Lycopodium AGP and 3-O-methyl-rhamnose for fern AGPs have been detected.
由于对非开花植物细胞壁结构的了解有限，目前人们对细胞壁进化的理解还不完整。除了多糖外，糖蛋白如阿拉伯半乳聚糖蛋白是大多数（如果不是全部的话）种子植物细胞壁的重要组成部分。本文首次详细描述了石松类植物和不同蕨类植物中 AGP 的特征，它们是与种子植物最接近的现存亲缘关系。蕨类植物 AGP 的蛋白含量（6-12%）与大多数种子植物的 AGP 相当，但石松类 AGP 的蛋白含量更高（17%）。所研究的 AGP 的碳水化合物部分表现出了与种子植物的 II 型阿拉伯半乳聚糖相同的典型特征，并与针对天蓝绣球 AGP 产生的多克隆抗体发生交叉反应。另一方面，还检测到了一些不常见的结构成分，如石松类 AGP 中大量的吡喃糖阿拉伯糖残基和蕨类植物 AGP 中的 3-O-甲基鼠李糖。
