Tarutani M, Norioka N, Mega T, Hase S, Ikenaka T
Department of Chemistry, Osaka University College of Science.
J Biochem. 1993 Jun;113(6):677-82. doi: 10.1093/oxfordjournals.jbchem.a124102.
The structures of the sugar chains of hen yolk riboflavin-binding protein (RBP) were established. Asparagine-linked sugar chains of yolk-RBP were liberated by hydrazinolysis. Free amino groups of the sugar chains were acetylated and the reducing-end sugar residues were tagged with 2-aminopyridine. Fluorescent pyridylamino (PA-) derivatives of the sugar chains were purified by gel-filtration and reversed-phase HPLC. Seven PA-sugar chains were isolated, and the structure of each was determined by composition analysis, sequential exoglycosidase digestion, methylation analysis, and 500-mHz 1H-NMR spectroscopy. These analyses showed that the main sugar chains had sialylbiantenna and sialyltriantenna structures. PA-sugar chains of plasma-RBP were also isolated, and the structures of the PA-sugar chains of yolk- and plasma-RBPs were compared as to their elution patterns on anion-exchange chromatography and reversed-phase HPLC. The plasma RBP had almost the same sugar chains as the yolk RBP did, indicating that sugar chains are not modified during incorporation into the oocyte.
已确定了母鸡蛋黄核黄素结合蛋白（RBP）糖链的结构。通过肼解作用释放出蛋黄RBP的天冬酰胺连接糖链。糖链的游离氨基被乙酰化，还原端糖残基用2-氨基吡啶标记。糖链的荧光吡啶氨基（PA-）衍生物通过凝胶过滤和反相高效液相色谱法纯化。分离出7条PA-糖链，每条糖链的结构通过组成分析、顺序外切糖苷酶消化、甲基化分析和500兆赫的1H-NMR光谱法确定。这些分析表明，主要糖链具有唾液酸双天线和唾液酸三天线结构。还分离出血浆RBP的PA-糖链，并比较了蛋黄和血浆RBP的PA-糖链在阴离子交换色谱和反相高效液相色谱上的洗脱模式。血浆RBP的糖链与蛋黄RBP的几乎相同，这表明糖链在并入卵母细胞的过程中没有被修饰。
