Sialic Acid Linkage Specific Derivatization of Glycosphingolipid Glycans by Ring-Opening Aminolysis of Lactones

作者：Hisatoshi Hanamatsu, Takashi Nishikaze, Nobuaki Miura, Jinhua Piao, Kazue Okada, Sadanori Sekiya, Shinichi Iwamoto, Naoya Sakamoto, Kōichi Tanaka, Jun‐ichi Furukawa · 发表于：Analytical Chemistry · 年份：2018 · DOI：10.1021/acs.analchem.8b02775 · 被引用次数：68 · 研究领域：Glycosylation and Glycoproteins Research、Carbohydrate Chemistry and Synthesis、Proteoglycans and glycosaminoglycans research

Sialic acids occur widely as glycoconjugates at the nonreducing ends of glycans. Glycosphingolipids (GSLs) include a large number of sialyl-linked glycan isomers with α2,3-, α2,6-, and α2,8-linked polysialic acids. Thus, it is difficult to distinguish structural isomers with the same mass by mass spectrometry. The sialic acid linkage specific alkylamidation (SALSA) method has been developed for discriminating between α2,3- and α2,6-linked isomers, but sequential amidation of linkage-specific sialic acids is generally complicated and time-consuming. Moreover, analysis of GSL-glycans containing α2,8-linked polysialic acids using solid-phase SALSA has not been reported. Herein, we report a novel SALSA method focused on ring-opening aminolysis (aminolysis-SALSA), which shortens the reaction time and simplifies the experimental procedures. We demonstrate that aminolysis-SALSA can successfully distinguish serum GSL-glycan isomers by mass spectrometry. In addition, ring-opening aminolysis can easily be applied to amine and hydrazine derivatives.