Nakagawa H, Zheng M, Hakomori S, Tsukamoto Y, Kawamura Y, Takahashi N
GlycoLab, Nakano Central Research Institute, Nakano Vinegar Co. Ltd, Handa-City, Japan.
Eur J Biochem. 1996 Apr 1;237(1):76-85. doi: 10.1111/j.1432-1033.1996.0076n.x.
Structures of N-linked oligosaccharides obtained from human integrin alpha 5 beta 1 are described. Integrin alpha 5 beta 1 (4.5 mg) was purified from human placenta and digested using trypsin and chymotrypsin. N-linked oligosaccharides were released from the glycopeptides by digestion with glycoamidase A (from almond). The reducing ends of the oligosaccharides were derivatized with 2-aminopyridine. The pyridylamino-oligosaccharides were separated and these structures were identified by a three-dimensional HPLC mapping technique on three kinds of HPLC columns [Takahashi, N., Nakagawa, H., Fujikawa, K., Kawamura, Y. & Tomiya, N. (1995) Anal. Biochem. 226, 139-146]. Finally, 35 different oligosaccharide structures were identified, 10 of which were neutral, 6 mono-sialyl, 10 di-sialyl, 7 tri-sialyl and 2 tetra-sialyl. The molar ratio of neutral, mono-sialyl, di-sialyl, tri-sialyl and tetra-sialyl oligosaccharides was 20.8%, 24.8%, 27.7%, 18.1% and 8.6%, respectively. High-mannose-type oligosaccharides accounted for only 1.5% of the total. The remaining oligosaccharides were all complex type. The most predominant structure was the diantennary di-alpha-(2,3)-sialyl fucosyl. Major linking of sialic acid was alpha-(2,3)-linkage, and over 50% of all oligosaccharides were fucosylated at the N-acetylglucosamine residue of the reducing end.
本文描述了从人整合素α5β1获得的N - 连接寡糖的结构。整合素α5β1（4.5毫克）从人胎盘中纯化出来，并用胰蛋白酶和糜蛋白酶进行消化。通过用杏仁来源的糖酰胺酶A消化，从糖肽中释放出N - 连接寡糖。寡糖的还原端用2 - 氨基吡啶进行衍生化。吡啶基氨基寡糖被分离出来，其结构通过在三种高效液相色谱柱上的三维高效液相色谱图谱技术进行鉴定[高桥，N.，中川，H.，藤川，K.，川村，Y.和富宫，N.（1995年）分析生物化学226，139 - 146]。最后，鉴定出35种不同的寡糖结构，其中10种是中性的，6种是单唾液酸的，10种是双唾液酸的，7种是三唾液酸的，2种是四唾液酸的。中性、单唾液酸、双唾液酸、三唾液酸和四唾液酸寡糖的摩尔比分别为20.8%、24.8%、27.7%、18.1%和8.6%。高甘露糖型寡糖仅占总量的1.5%。其余的寡糖均为复合型。最主要的结构是双触角二α - (2,3) - 唾液酸化岩藻糖基化结构。唾液酸的主要连接方式是α - (2,3) - 连接，并且超过50%的所有寡糖在还原端的N - 乙酰葡糖胺残基处被岩藻糖基化。
