Linkage and branch analysis of high-mannose oligosaccharides using closed-ring labeling of 8-aminopyrene-1,3,6-trisulfonate and p-aminobenzoic ethyl ester and negative ion trap mass spectrometry.
A strategy based on negative ion electrospray ionization tandem mass spectrometry and closed-ring labeling with both 8-aminopyrene-1,3,6-trisulfonate (APTS) and p-aminobenzoic acid ethyl ester (ABEE) was developed for linkage and branch determination of high-mannose oligosaccharides. X-type cross-ring fragment ions obtained from APTS-labeled oligosaccharides by charge remote fragmentation provided information on linkages near the non-reducing terminus. In contrast, A-type cross-ring fragment ions observed from ABEE-labeled oligosaccharides yielded information on linkages near the reducing terminus. This complementary information provided by APTS- and ABEE-labeled oligosaccharides was utilized to delineate the structures of the high-mannose oligosaccharides. As a demonstration of this approach, the linkages and branches of high-mannose oligosaccharides Man(5)GlcNAc(2), Man(6)GlcNAc(2), Man(8)GlcNAc(2), and Man(9)GlcNAc(2) cleaved from the ribonuclease B were assigned from MS(2) spectra of ABEE- and APTS-labeled derivatives.
Department of Chemistry, National Taiwan University, Taipei, Taiwan.
Shu-Ting
ST
Chen
Guor-Rong
GR
Her
D010129:4-Aminobenzoic Acid / Q000737:chemistry*; D008358:Mannose / Q000737:chemistry*; D008958:Models, Molecular; D009844:Oligosaccharides / Q000737:chemistry*; D011721:Pyrenes / Q000737:chemistry*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
C103430:8-aminopyrene-1,3,6-trisulfonic acid; D009844:Oligosaccharides; D011721:Pyrenes; D008358:Mannose; D010129:4-Aminobenzoic Acid