生孢噬纤维菌荚膜多糖的分离纯化及其性质

Isolation, Purification and Characters of Capsular Polysaccharide of Sporocytophaga

生孢噬纤维菌(Sporocytophaga)是能降解纤维素的滑动细菌,它可将滤纸和棉花纤维素完全降解.本文对生孢噬纤维菌产生的荚膜多糖的分离纯化以及性质进行了研究.以滤纸平板法培养生孢噬纤维菌,加入1%苯酚后,荚膜多糖溶解在水相中,再经氯化十六烷基吡啶(CPC)沉淀,分离出荚膜多糖提取物.利用Sephadex G-75柱层析法、胰蛋白酶和Sevag法对荚膜多糖提取物进行纯化;并利用比旋光度检查、红外光谱、液相色谱以及气相色谱等分析手段对精制后的荚膜多糖进行分析.结果表明,分离纯化得到了纯度较高的生孢噬纤维菌荚膜多糖.Sephadex G-75柱层析分析表明,荚膜多糖提取物中含有结合蛋白,除去结合蛋白后,多糖分子量约为6.5×103;气相色谱分析表明,该荚膜多糖主要由Gal、Glc、GlcA以及Man等单糖组成,其比值约为3.513.33.61;同时该荚膜多糖的红外光谱显示,该多糖所含的甲基、亚甲基等基团的量比正常多糖多;红外光谱图中881cm-1处的峰位显示,该多糖含有不典型β糖苷键特征吸收峰.

Sporocytophaga was a kind of bacteria that can glide on the surface of solid medium, decomposing cotton and filter paper completely after 6 days culture. The isolation, purification and characters of capsular polysaccharide from Sporocytophaga sp. JL-01 were described. The capsular polysaccharide of Sporocytophaga sp. JL-01 was isolated with CPC precipitation and further purified by gel chromatography on Sephadex G-75. The molecular weight and constitute analysis showed that the molecular weight of this capsular polysaccharide was 6.5 × 10^3. The capsular polysaccharide consisted of galactose, glucose, glucuronic acid and mannan at a molarity rate of nGal ： nGlu ： nGluA ： nMnn = 3.5 ： 13. 3 ： 3.6 ： 1. The IR analysis showed that capsular poly- saccharide was a mixture of a-linkage and β-linkage with more methyl group than other polysaccharide. Fig 5, Ref 8