Nimtz M, Mort A, Domke T, Wray V, Zhang Y, Qiu F, Coplin D, Geider K
GBF, Gesellschaft für Biotechnologische Forschung mbH, Braunschweig, Germany.
Carbohydr Res. 1996 Jun 7;287(1):59-76. doi: 10.1016/0008-6215(96)00070-5.
The acidic exopolysaccharide (EPS) of Erwinia amylovora, amylovoran, was purified from culture supernatants of bacteria in minimal medium and cleaved chemically either by treatment with trifluoracetic acid or hydrofluoric acid, and enzymatically by digestion with depolymerase from E. amylovora phage phi-Ealh. Structural characterization of the resulting oligosaccharides was performed by a combination of mass spectrometric and NMR [one- and two-dimensional (1D and 2D)] spectroscopic techniques. A branched repeating unit with five monosaccharide residues and various substituents was determined: [sequence: see text] The terminal monosaccharide of the side branch, which bears a 4,6-bound pyruvate residue in the R-configuration, was found to be modified with 2-linked (26%), 3-linked (24%), 2-,3-linked (40%) O-acetyl groups, or these were absent (10%). An additional glucose residue is linked to approximately 10% of the core alpha-galactose of the repeating unit.
从苹果果胶杆菌（Erwinia amylovora）的培养上清液中纯化出其酸性胞外多糖（EPS）——淀粉果聚糖（amylovoran），该多糖在基本培养基中培养获得。通过用三氟乙酸或氢氟酸处理进行化学裂解，并用来自苹果果胶杆菌噬菌体phi-Ealh的解聚酶进行酶解。通过质谱和核磁共振[一维和二维（1D和2D）]光谱技术相结合的方法对所得寡糖进行结构表征。确定了一个具有五个单糖残基和各种取代基的分支重复单元：[序列：见原文]发现侧链末端单糖带有R构型的4,6-连接丙酮酸残基，其被2-连接（26%）、3-连接（24%）、2,3-连接（40%）的O-乙酰基修饰，或者不存在这些修饰（10%）。另外，一个葡萄糖残基与大约10%的重复单元核心α-半乳糖相连。
