Inoue N, Takeuchi M, Asano K, Shimizu R, Takasaki S, Kobata A
Pharmaceutical Laboratory of Kirin Brewery Co. Ltd., Gumma, Japan.
Arch Biochem Biophys. 1993 Mar;301(2):375-8. doi: 10.1006/abbi.1993.1158.
Less is known about the mucin-type sugar chains attached to human erythropoietin as compared with N-linked sugar chains which structures and function have been well studied. In this study, we purified urinary human erythropoietin from three independent groups of aplastic anemia patients, and analyzed the structures of mucin-type sugar chains as well as that obtained from recombinant human erythropoietin produced by Chinese hamster ovary cells. Unlike the N-linked sugar chains, the mucin-type sugar chains are totally different between the urinary and the recombinant erythropoietins. All of the three independent samples of urinary erythropoietin contained oligosaccharides with the structures of +/- Neu5Ac alpha 2-->6GalNAc, while recombinant human erythropoietin contained those with the structures of Neu5Ac alpha 2-->3Gal beta 1-->3(Neu5Ac alpha 2-->6)GalNAc, Neu5Ac alpha 2-->3Gal beta 1-->3GalNAc, and Gal beta 1-->3(Neu5Ac alpha 2-->6)GalNAc.
与结构和功能已得到充分研究的N-连接糖链相比，人们对连接在人促红细胞生成素上的粘蛋白型糖链了解较少。在本研究中，我们从三组独立的再生障碍性贫血患者中纯化出尿源性人促红细胞生成素，并分析了粘蛋白型糖链的结构，以及从中国仓鼠卵巢细胞产生的重组人促红细胞生成素中获得的糖链结构。与N-连接糖链不同，尿源性和重组促红细胞生成素中的粘蛋白型糖链完全不同。尿促红细胞生成素的所有三个独立样本都含有结构为+/-Neu5Acα2-->6GalNAc的寡糖，而重组人促红细胞生成素则含有结构为Neu5Acα2-->3Galβ1-->3(Neu5Acα2-->6)GalNAc、Neu5Acα2-->3Galβ1-->3GalNAc和Galβ1-->3(Neu5Acα2-->6)GalNAc的寡糖。
