Zhou G H, Luo G A, Zhou Y, Zhou K Y, Zhang X D, Huang L Q
Department of Chemistry, Tsinghua University, Beijing, PRC.
Electrophoresis. 1998 Oct;19(13):2348-55. doi: 10.1002/elps.1150191315.
High performance capillary electrophoresis (HPCE), high performance liquid chromatography (HPLC), matrix-assisted laser desorption/ionization - time of flight - mass spectrometry (MALDI-TOF-MS), on-line CE-electrospray ionization-mass spectrometry (CE-ESI-MS) and on-line LC-ESI-MS have been employed to characterize a heterogeneous glycoprotein, recombinant human erythropoietin (rHuEPO) expressed from Chinese hamster ovary (CHO) cells. The analysis was demonstrated through two specific levels of detail: the intact protein and tryptic digests of the protein. Six glycoforms of rHuEPO were separated by HPCE; seventeen tryptic fragments in a total of 21 nonglycosylated and glycosylated peptides were characterized; the O-linked glycopeptides were analyzed directly by CE-ESI-MS and LC-ESI-MS. In particular, four glycans of O-acetylation of sialic acid were identified in the O-linked glycosylated fragments. The molecular weight of rHuEPO was accurately determined by MALDI-TOF-MS.
高效毛细管电泳（HPCE）、高效液相色谱（HPLC）、基质辅助激光解吸/电离飞行时间质谱（MALDI-TOF-MS）、在线CE-电喷雾电离质谱（CE-ESI-MS）和在线LC-ESI-MS已被用于表征一种异质性糖蛋白，即从中国仓鼠卵巢（CHO）细胞表达的重组人促红细胞生成素（rHuEPO）。分析通过两个特定的详细程度进行：完整蛋白质和蛋白质的胰蛋白酶消化产物。通过HPCE分离出六种rHuEPO糖型；对总共21种非糖基化和糖基化肽中的17个胰蛋白酶片段进行了表征；通过CE-ESI-MS和LC-ESI-MS直接分析O-连接糖肽。特别地，在O-连接糖基化片段中鉴定出四种唾液酸O-乙酰化聚糖。通过MALDI-TOF-MS准确测定了rHuEPO的分子量。
