Kameyama Akihiko, Kikuchi Norihiro, Nakaya Shuuichi, Ito Hiromi, Sato Takashi, Shikanai Toshihide, Takahashi Yoriko, Takahashi Katsutoshi, Narimatsu Hisashi
Research Center for Glycoscience, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8568, Japan.
Anal Chem. 2005 Aug 1;77(15):4719-25. doi: 10.1021/ac048350h.
Glycosylation is the most widespread posttranslational modification in eukaryotes; however, the role of oligosaccharides attached to proteins has been little studied because of the lack of a sensitive and easy analytical method for oligosaccharide structures. Recently, tandem mass spectrometric techniques have been revealing that oligosaccharides might have characteristic signal intensity profiles. We describe here a strategy for the rapid and accurate identification of the oligosaccharide structures on glycoproteins using only mass spectrometry. It is based on a comparison of the signal intensity profiles of multistage tandem mass (MSn) spectra between the analyte and a library of observational mass spectra acquired from structurally defined oligosaccharides prepared using glycosyltransferases. To smartly identify the oligosaccharides released from biological materials, a computer suggests which ion among the fragment ions in the MS/MS spectrum should yield the most informative MS3 spectrum to distinguish similar oligosaccharides. Using this strategy, we were able to identify the structure of N-linked oligosaccharides in immunoglobulin G as an example.
糖基化是真核生物中最普遍的翻译后修饰；然而，由于缺乏一种灵敏且简便的寡糖结构分析方法，附着在蛋白质上的寡糖的作用鲜有研究。最近，串联质谱技术已揭示出寡糖可能具有特征性的信号强度谱。我们在此描述一种仅使用质谱就能快速准确鉴定糖蛋白上寡糖结构的策略。它基于分析物与从使用糖基转移酶制备的结构明确的寡糖获得的观测质谱库之间的多级串联质谱（MSn）谱的信号强度谱比较。为了巧妙地鉴定从生物材料中释放的寡糖，计算机可提示MS/MS谱中的碎片离子中哪个离子应产生信息量最大的MS3谱以区分相似的寡糖。以免疫球蛋白G中的N - 连接寡糖结构鉴定为例，我们利用此策略成功实现了结构鉴定。
