Nimtz M, Noll G, Pâques E P, Conradt H S
Department of Cell Biology and Genetics, GBF-Gesellschaft für Biotechnologische Forschung mbH, Braunschweig, FRG.
FEBS Lett. 1990 Oct 1;271(1-2):14-8. doi: 10.1016/0014-5793(90)80361-l.
The carbohydrate structures of a genetically engineered human tissue plasminogen activator variant bearing a single N-glycosylation site at Asn 448 are reported. After isolation of the tryptic glycopeptide and liberation of the N-linked carbohydrates by polypeptide:N-glycosidase F, 6 major oligosaccharide fractions were separated by HPLC on NH2-bonded phase. Their structures were determined by compositional and methylation analyses combined with fast atom bombardment mass spectrometry. Seventy percent of the carbohydrates were of the biantennary complex type with fucose at the proximal GlcNAc and zero, one or two alpha 2-3 linked NeuAc. The remainder were triantennary structures with one, two or three NeuAc.
报道了一种在Asn 448处带有单个N-糖基化位点的基因工程人组织纤溶酶原激活剂变体的碳水化合物结构。在分离出胰蛋白酶糖肽并用多肽：N-糖苷酶F释放N-连接的碳水化合物后，通过在NH2键合相上的HPLC分离出6个主要的寡糖级分。通过组成分析、甲基化分析以及快原子轰击质谱法确定了它们的结构。70%的碳水化合物是双触角复合型，在近端GlcNAc处带有岩藻糖，并且有零个、一个或两个α2-3连接的NeuAc。其余的是带有一个、两个或三个NeuAc的三触角结构。
