title: Novel acetylation-aided migrating rearrangement of uridine-diphosphate-N-acetylglucosamine in electrospray ionization multistage tandem mass spectrometry.
abstract: Uridine 5'-diphospho-N-acetylglucosamine (UDP-GlcNAc) is the final product of hexosamine biosynthetic pathway (HSP) and the donor substrate for the modification of nucleocytoplasmic proteins at serine and threonine residues with N-acetylglucosamine (GlcNAc) catalyzed by O-GlcNAc transferase (OGT). Many analogs of UDP-GlcNAc were designed to interfere with the process of protein O-glycosylation by blocking OGT. A novel rearrangement reaction was observed in which phosphate-N-acetylglucosamine moiety migrated to 3' terminus of ribose in ESI-MS(n) of UDP-GlcNAc. Results from tandem mass spectrometry, control experiments and calculation showed that the phosphate-N-acetylglucosamine migration might undergo a pentacoordinate phosphoric intermediate. Furthermore, the acetylation of glucosamine in UDP-GlcNAc was essential in the migration process.
authors.affiliation: Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084, PR China.
authors.forename: Hua-Dong
authors.initials: HD
authors.lastname: Liu
authors.forename: Yan-Mei
authors.initials: YM
authors.lastname: Li
authors.forename: Jin-Tang
authors.initials: JT
authors.lastname: Du
authors.forename: Jia
authors.initials: J
authors.lastname: Hu
authors.forename: Yu-Fen
authors.initials: YF
authors.lastname: Zhao
mesh_terms: D000107:Acetylation; D008958:Models, Molecular; D021241:Spectrometry, Mass, Electrospray Ionization; D014537:Uridine Diphosphate N-Acetylglucosamine / Q000032:analysis / Q000737:chemistry*
chemical_list: D014537:Uridine Diphosphate N-Acetylglucosamine