An J, O'Neill M A, Albersheim P, Darvill A G
Complex Carbohydrate Research Center, University of Georgia, Athens 30602-4712.
Carbohydr Res. 1994 Jan 15;252:235-43. doi: 10.1016/0008-6215(94)90018-3.
Rhamnogalacturonan I (RG-I), a pectic polysaccharide isolated from the walls of suspension-cultured sycamore cells, was shown by glycosyl-residue composition analysis to contain D-glucosyluronic acid (GlcpA) residues (1 mol%) and 4-O-methyl-D-glucosyluronic acid (4-O-Me-GlcpA) residues (0.5 mol%). These monosaccharides were shown, by glycosyl-linkage analysis, to be present in RG-I as terminal nonreducing residues. The glycosyl sequences containing GlcpA and 4-O-Me-GlcpA were determined by structurally characterizing the acidic oligosaccharides released by partial acid hydrolysis of RG-I. Six acidic oligosaccharides were purified by semipreparative high-performance anion-exchange chromatography with pulsed amperometric detection (HPAEC-PAD) and characterized by glycosyl-residue and glycosyl-linkage composition analyses, GLC-CIMS, GLC-EIMS, electrospray MS (ESMS), and 1H NMR spectroscopy. We propose that three of the acidic oligosaccharides characterized, 4-O-Me-beta-D-GlcpA-(1-->6)-D-Gal, beta-D-GlcpA-(1-->6)-D-Gal, and beta-D-GlcpA-(1-->4)-D-Gal, originate from the galactosyl-containing side chains of RG-I. The three other acidic oligosaccharides characterized, alpha-D-GalpA-(1-->2)-L-Rha, alpha-D-GalpA-(1-->2)-alpha-L-Rhap-(1-->4)-alpha-D-GalpA+ ++-(1-->2)-alpha-L-Rha, and alpha-D-GalpA-(1-->2)-alpha-L-Rhap-(1-->4)-alpha-D-GalpA+ ++-(1-->2)-alpha-L- Rhap-(1-->4)-alpha-D-GalpA-(1-->2)-alpha-L-Rha, were generated by partial hydrolysis of the RG-I backbone. No evidence was obtained for the presence of galactosyluronic acid in the side chains of RG-I.(ABSTRACT TRUNCATED AT 250 WORDS)
鼠李半乳糖醛酸聚糖I（RG-I）是一种从悬浮培养的悬铃木细胞的细胞壁中分离得到的果胶多糖，通过糖基残基组成分析表明其含有D-葡萄糖醛酸（GlcpA）残基（1摩尔%）和4-O-甲基-D-葡萄糖醛酸（4-O-Me-GlcpA）残基（0.5摩尔%）。通过糖基连接分析表明，这些单糖在RG-I中以末端非还原残基的形式存在。通过对RG-I部分酸水解释放的酸性寡糖进行结构表征，确定了含有GlcpA和4-O-Me-GlcpA的糖基序列。通过半制备高效阴离子交换色谱-脉冲安培检测（HPAEC-PAD）纯化了六种酸性寡糖，并通过糖基残基和糖基连接组成分析、气相色谱-化学电离质谱（GLC-CIMS）、气相色谱-电子电离质谱（GLC-EIMS）、电喷雾质谱（ESMS）和1H核磁共振光谱对其进行了表征。我们提出，所表征的三种酸性寡糖，4-O-Me-β-D-GlcpA-(1→6)-D-Gal、β-D-GlcpA-(1→6)-D-Gal和β-D-GlcpA-(1→4)-D-Gal，源自RG-I含半乳糖的侧链。所表征的另外三种酸性寡糖，α-D-GalpA-(1→2)-L-Rha、α-D-GalpA-(1→2)-α-L-Rhap-(1→4)-α-D-GalpA+(1→2)-α-L-Rha和α-D-GalpA-(1→2)-α-L-Rhap-(1→4)-α-D-GalpA+(1→2)-α-L-Rhap-(1→4)-α-D-GalpA-(1→2)-α-L-Rha，是由RG-I主链的部分水解产生的。没有获得RG-I侧链中存在半乳糖醛酸的证据。（摘要截短于250字）
