Makarova Elena N, Shakhmatov Evgeny G
Institute of Chemistry, Federal Research Center "Komi Science Center of the Ural Branch of the Russian Academy of Sciences", Pervomaiskaya St. 48, Syktyvkar, 167982, Russia.
Institute of Chemistry, Federal Research Center "Komi Science Center of the Ural Branch of the Russian Academy of Sciences", Pervomaiskaya St. 48, Syktyvkar, 167982, Russia.
Carbohydr Polym. 2021 May 15;260:117825. doi: 10.1016/j.carbpol.2021.117825. Epub 2021 Feb 16.
Polysaccharide AS was isolated from the Abies sibirica foliage by extraction with an aqueous KOH solution. AS was shown to contain structurally different polymers such as arabinoglucuronoxylans, xyloglucans, glucomannans, arabinogalactan-proteins (AGPs). The pectic polysaccharides were also found in the alkaline extract of AS and were represented by regions of homogalactorunan and rhamnogalactouronan-I whose side sugar chains were made up chiefly of highly branched 1,5-α-l-arabinan. The potential couplings between those polysaccharides were examined. Our studies showed simultaneous elution of pectin, xyloglucans, arabinoglucuronoxylans and AGPs, indicating that pectins can be covalently bound to the other cell-wall polysaccharides. NMR spectroscopy results revealed that the polysaccharides obtained by ion-exchange chromatography almost had no free reducing ends. These findings corroborate the conclusion that pectin, AGPs, glucan and xylan are bound together. The existence of the covalently bound complex of pectin-xylan-xyloglucan-AGP is suggested herein. Pectin and xylan are hypothesized to be covalently linked through RG-I regions.
通过用氢氧化钾水溶液提取，从西伯利亚冷杉树叶中分离出多糖AS。结果表明，AS含有结构不同的聚合物，如阿拉伯糖基葡萄糖醛酸木聚糖、木葡聚糖、葡甘露聚糖、阿拉伯半乳聚糖蛋白（AGP）。在AS的碱性提取物中也发现了果胶多糖，其由同型半乳糖醛酸聚糖和鼠李糖半乳糖醛酸聚糖-I区域代表，其侧糖链主要由高度分支的1,5-α-L-阿拉伯聚糖组成。研究了这些多糖之间的潜在偶联。我们的研究表明，果胶、木葡聚糖、阿拉伯糖基葡萄糖醛酸木聚糖和AGP同时洗脱，表明果胶可以与其他细胞壁多糖共价结合。核磁共振光谱结果显示，通过离子交换色谱获得的多糖几乎没有游离还原端。这些发现证实了果胶、AGP、葡聚糖和木聚糖结合在一起的结论。本文提出了果胶-木聚糖-木葡聚糖-AGP共价结合复合物的存在。推测果胶和木聚糖通过RG-I区域共价连接。
