title: Composition, sequencing and ion mobility mass spectrometry of heparan sulfate-like octasaccharide isomers differing in glucuronic and iduronic acid content.
abstract: Here we report ion mobility mass spectrometry (IMMS) separation and tandem mass spectrometry (MS(2)) sequencing methods used to analyze and differentiate six synthetically produced heparin/heparan sulfate (HS)-like octasaccharide (dp8) isomeric structures. These structures are isomeric with regard to either glucuronic acid (GlcA) or iduronic acid (IdoA) residues at various positions. IMMS analysis showed that a fully GlcA structure exhibited a more compact conformation, whereas the fully IdoA structure was more extended. Interestingly, the change from IdoA to GlcA in specific locations resulted in strong conformational distortions. MS(2) of the six isomers showed very different spectra with unique sets of diagnostic product ions. Analysis of MS(2) product ion spectra suggests that the GlcA group correlated with the formation of a glycosidic product ion under lower energy conditions. This resulted in an earlier product ion formation and more intense product ions. Importantly, this knowledge enabled a complete sequencing of the positions of GlcA and IdoA in each of the four positions located in each unique dp8 structure.
authors: De partments of Molecular and Cellular Biology and Chemistry, University of California, USA.. jaleary@ucdavis.edu.
authors: Julie A
authors: JA
authors: Leary
authors: Departments of Molecular and Cellular Biology and Chemistry, University of California. Centre for Glycobiology, Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool, L69 7ZB, UK. becky@liv.ac.uk.
authors: Rebecca L
authors: RL
authors: Miller
authors: Departments of Molecular and Cellular Biology and Chemistry, University of California, USA.. viwei@ucdavis.edu.
authors: Wei
authors: W
authors: Wei
authors: Ferrier Research Institute, Victoria University of Wellington, 69 Gracefield Road, Gracefield, Lower Hutt 5010, New Zealand. ralf.schwoerer@vuw.ac.nz.
authors: Ralf
authors: R
authors: Schwörer
authors: Ferrier Research Institute, Victoria University of Wellington, 69 Gracefield Road, Gracefield, Lower Hutt 5010, New Zealand. olga.zubkova@vuw.ac.nz.
authors: Olga V
authors: OV
authors: Zubkova
authors: Ferrier Research Institute, Victoria University of Wellington, 69 Gracefield Road, Gracefield, Lower Hutt 5010, New Zealand. peter.tyler@vuw.ac.nz.
authors: Peter C
authors: PC
authors: Tyler
authors: Centre for Glycobiology, Institute of Integrative Biology, University of Liverpool, Crown Street, Liverpool, L69 7ZB, UK. j.turnbull@liverpool.ac.uk.
authors: Jeremy E
authors: JE
authors: Turnbull
mesh_terms: D001665:Binding Sites; D020723:Glucuronic Acid / Q000737:chemistry*; D006497:Heparan Sulfate / Q000032:analysis / Q000737:chemistry*; D007067:Iduronic Acid / Q000737:chemistry*; D007536:Isomerism; D011134:Polysaccharides / Q000737:chemistry*; D017421:Sequence Analysis / Q000379:methods*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
chemical_list: D020723:Glucuronic Acid; D006497:Heparan Sulfate; D007067:Iduronic Acid; D011134:Polysaccharides