title: Characterizing the microstructure of heparin and heparan sulfate using N-sulfoglucosamine 1H and 15N NMR chemical shift analysis.
abstract: Heparin and heparan sulfate (HS) are members of a biologically important group of highly anionic linear polysaccharides called glycosaminoglycans (GAGs). Because of their structural complexity, the molecular-level characterization of heparin and HS continues to be a challenge. The work presented herein describes an emerging approach for the analysis of unfractionated and low molecular weight heparins, as well as porcine and human-derived HS. This approach utilizes the untapped potential of (15)N NMR to characterize these preparations through detection of the NH resonances of N-sulfo-glucosamine residues. The sulfamate group (1)H and (15)N chemical shifts of six GAG microenvironments were assigned based on the critical comparison of selectively modified heparin derivatives, NMR measurements for a library of heparin-derived oligosaccharide standards, and an in-depth NMR analysis of the low molecular weight heparin enoxaparin through systematic investigation of the chemical exchange properties of NH resonances and residue-specific assignments using the [(1)H,(15)N] HSQC-TOCSY experiment. The sulfamate microenvironments characterized in this study include GlcNS(6S)-UA(2S), ΔUA(2S)-GlcNS(6S), GlcNS(3S)(6S)-UA(2S), GlcNS-UA, GlcNS(6S)-red(α), and 1,6-anhydro GlcNS demonstrating the utility of [(1)H,(15)N] HSQC NMR spectra to provide a spectroscopic fingerprint reflecting the composition of intact GAGs and low molecular weight heparin preparations.
authors.affiliation: Department of Chemistry, University of California-Riverside, Riverside, CA, USA.
authors.forename: Derek J
authors.initials: DJ
authors.lastname: Langeslay
authors.forename: Consuelo N
authors.initials: CN
authors.lastname: Beecher
authors.forename: Annamaria
authors.initials: A
authors.lastname: Naggi
authors.forename: Marco
authors.initials: M
authors.lastname: Guerrini
authors.forename: Giangiacomo
authors.initials: G
authors.lastname: Torri
authors.forename: Cynthia K
authors.initials: CK
authors.lastname: Larive
mesh_terms: D002236:Carbohydrate Conformation; D002478:Cells, Cultured; D005944:Glucosamine / Q000031:analogs & derivatives* / Q000737:chemistry; D057809:HEK293 Cells; D006493:Heparin / Q000737:chemistry*; D006497:Heparan Sulfate / Q000737:chemistry* / Q000302:isolation & purification; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000592:standards; D009587:Nitrogen Isotopes; D011522:Protons; D012015:Reference Standards
chemical_list: D005944:Glucosamine; D006493:Heparin; D006497:Heparan Sulfate; D009587:Nitrogen Isotopes; D011522:Protons