Structures and Structure-Activity Relationships of Three Mitogenic and Complement Fixing Pectic Arabinogalactans from the Malian Antiulcer Plants Cochlospermum tinctorium A. Rich
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- 作者：Cecilie Sogn Nergard ; Hiroaki Kiyohara ; James C. Reynolds ; Jane E. Thomas-Oates ; Tsukasa Matsumoto ; Haruki Yamada ; Trushar Patel ; Dirk Petersen ; Terje E. Michaelsen ; Drissa Diallo ; and Berit Smestad P
- 刊名：Biomacromolecules
- 出版年：2006
- 出版时间：January 2006
- 年：2006
- 卷：7
- 期：1
- 页码：71 - 79
- 全文大小：188K
- 年卷期：v.7,no.1(January 2006)
- ISSN：1526-4602
文摘
Structures of three pectic arabinogalactans, one from Vernonia kotschyana (Vk2a) and two from Cochlospermumtinctorium (Ct50A1 and Ct50A2), and their complement fixation and induction of B cell proliferation in vitrowere compared. The polysaccharide Vk2a expressed potent biological activity in both assays compared withCt50A1 and Ct50A2. Vk2a possessed a very high molecular weight (1150 ± 20 kDa) compared with Ct50A1and Ct50A2 which both showed a polydisperse nature with the highest molecular weight polymers in each fractionestimated at ~105 kDa (Ct1a) and 640 ± 100 kDa (Ct2a), respectively. The HMW polymers showed complementfixation in the same range as the native fractions. The arabinogalactan II content was low in Vk2a (2%) comparedwith that in Ct50A1 (23%) and Ct50A2 (12%). The high molecular weight polymers were subjected to digestionwith a 
-D-(1, 3)-galactanase-rich fraction from Driselase, oligomers were isolated by HPAEC, and their finerstructures were determined by MALDI- and ES-qoToF-MS, linkage, and monosaccharide composition analyses.Vk2a consists of both a galacturonan core and a rhamnogalacturonan core rich in neutral side chains. The backbonesof both Ct-polysaccharides consist mainly of RG-I regions with numerous neutral side chains dominated bygalactosyl residues, whereas the homogalacturonan regions seem to be small. Differences in the chain lengths ofthe 6-linked galacto-oligosaccharides attached to the 3-linked galactan core could not be related to the differencesin the potencies of the biological activities observed.
-D-(1, 3)-galactanase-rich fraction from Driselase, oligomers were isolated by HPAEC, and their finerstructures were determined by MALDI- and ES-qoToF-MS, linkage, and monosaccharide composition analyses.Vk2a consists of both a galacturonan core and a rhamnogalacturonan core rich in neutral side chains. The backbonesof both Ct-polysaccharides consist mainly of RG-I regions with numerous neutral side chains dominated bygalactosyl residues, whereas the homogalacturonan regions seem to be small. Differences in the chain lengths ofthe 6-linked galacto-oligosaccharides attached to the 3-linked galactan core could not be related to the differencesin the potencies of the biological activities observed.