Hård K, Bitter W, Kamerling J P, Vliegenthart J F
Department of Bio-Organic Chemistry, Utrecht University, The Netherlands.
FEBS Lett. 1989 May 8;248(1-2):111-4. doi: 10.1016/0014-5793(89)80442-9.
A glycosylated form of recombinant human insulin-like growth factor I (IGF-I) expressed in Saccharomyces cerevisiae was shown to contain mannose as the only carbohydrate constituent. All oligosaccharide chains of the glycoprotein could be released by mild alkaline treatment, and separated from the protein by gel-permeation chromatography on Bio-Gel P-2. The structures of these O-linked carbohydrate chains were determined by 500-MHz 1H-NMR spectroscopy, affording the disaccharide Man alpha 1-2Man as the major component and the tetrasaccharide Man alpha 1-3Man alpha 1-2Man alpha 1-2Man as a minor component. Reference oligosaccharides were prepared from mannoproteins released from the cell wall of S. cerevisiae X2180 (alpha-wild type). In addition to previously reported structures, ranging from mannose to mannotetraose, the pentasaccharide Man alpha 1-3Man alpha 1-3Man alpha 1-2Man alpha 1-2Man was identified in the cell wall mannoprotein.
在酿酒酵母中表达的重组人胰岛素样生长因子I（IGF-I）的糖基化形式被证明仅含有甘露糖作为唯一的碳水化合物成分。糖蛋白的所有寡糖链都可以通过温和的碱性处理释放出来，并通过在Bio-Gel P-2上的凝胶渗透色谱法与蛋白质分离。这些O-连接的碳水化合物链的结构通过500兆赫兹的1H-NMR光谱法确定，主要成分是二糖Manα1-2Man，次要成分是四糖Manα1-3Manα1-2Manα1-2Man。参考寡糖是从酿酒酵母X2180（α-野生型）细胞壁释放的甘露糖蛋白制备的。除了先前报道的从甘露糖到甘露四糖的结构外，还在细胞壁甘露糖蛋白中鉴定出了五糖Manα1-3Manα1-3Manα1-2Manα1-2Man。
