Bhattacharjee A K, Jennings H J, Kenny C P, Martin A, Smith I C
Can J Biochem. 1976 Jan;54(1):1-8. doi: 10.1139/o76-001.
The purified high molecular weight serogroup Y meningococcal polysaccharide contains equimolar proportions of D-glucose and N-acetylneuraminic acid and is partially O-acetylated. Carbon-13 nuclear magnetic resonance (NMR) studies, together with other chemical data, have indicated that the polysaccharide is linked only at C-6 of the D-glucose and C-4 of the sialic acid residues, all the linkages being in the alpha-configuration. The 13CNMR data also indicated that the Y polysaccharide is composed of an alternating sequence of these two different residues, and this was confirmed by its autohydrolysis where the major product was 4-O-alpha-D-glucopyranosyl-beta-D-N-acetylneuraminic acid. The W-135 polysaccharide differs from that of Y only in the absence of O-acetylation and in the configuration of one hydroxyl group of the disaccharide repeating unit. In this case autohydrolysis yielded 4-O-alpha-D-galactopyranosyl-beta-D-N-acetylneuraminic acid as the major product. Structural evidence indicates that the BO and Y polysaccharides are identical. Methanolysis of the Y polysaccharide yielded in addition to the methyl glycosides of glucose and sialic acid, a 9-O-acetyl derivative of the latter. This derivative was formed during the re-N-acetylation process and its formation was mainly due to the presence of sodium ions in the original polysaccharide.
纯化的高分子量Y群脑膜炎球菌多糖含有等摩尔比例的D-葡萄糖和N-乙酰神经氨酸，且部分被O-乙酰化。碳-13核磁共振（NMR）研究以及其他化学数据表明，该多糖仅在D-葡萄糖的C-6位和唾液酸残基的C-4位连接，所有连接均为α构型。13C NMR数据还表明，Y多糖由这两种不同残基的交替序列组成，这一点通过其自水解得到证实，其主要产物是4-O-α-D-吡喃葡萄糖基-β-D-N-乙酰神经氨酸。W-135多糖与Y多糖的不同之处仅在于不存在O-乙酰化以及二糖重复单元的一个羟基的构型。在这种情况下，自水解产生4-O-α-D-吡喃半乳糖基-β-D-N-乙酰神经氨酸作为主要产物。结构证据表明，B群和Y群多糖是相同的。Y多糖的甲醇解除了产生葡萄糖和唾液酸的甲基糖苷外，还产生了后者的9-O-乙酰衍生物。该衍生物在重新N-乙酰化过程中形成，其形成主要归因于原始多糖中存在钠离子。
