title: Structural determination of novel tetra- and hexasaccharide sequences isolated from chondroitin sulfate H (oversulfated dermatan sulfate) of hagfish notochord.
abstract: Oversulfated chondroitin sulfate H (CS-H) isolated from hagfish notochord is a unique dermatan sulfate consisting mainly of IdoAalpha1-3GalNAc(4S,6S), where IdoA, GalNAc, 4S and 6S represent L-iduronic acid, Nacetyl-D-galactosamine, 4-O-sulfate and 6-O-sulfate, respectively. Several tetra- and hexasccharide fractions were isolated from CS-H after partial digestion with bacterial chondroitinase B to investigate the sequential arrangement of the IdoAalpha1-3GalNAc(4S,6S) unit in the CS-H polysaccharide. A structural analysis of the isolated oligosaccharides by enzymatic digestions, mass spectrometry and 1H NMR spectroscopy demonstrated that the major tetrasaccharides shared the common disulfated core structure delta4,5HexAalpha1-3GalNAc(4S)beta1-4IdoAalpha1-3 GalNAc (4S) with 0 approximately 3 additional O-sulfate groups, where delta4,5HexA represents 4-deoxy-alpha-L-threo-hex-4-enepyranosyluronic acid. The major hexasaccharides shared the common trisulfated core structure delta4,5HexAalpha1-3 GalNAc(4S)beta1-4 IdoAalpha1-3 GalNAc(4S)beta1-4IdoAalpha1-3 GalNAc(4S) with 1 approximately 4 additional O-sulfate groups. Some extra sulfate groups in both tetra- and hexasaccharides were located at the C-2 position of a delta4,5HexA or an internal IdoA residue, or C-6 position of 4-O-sulfated GalNAc residues, forming the unique disulfated or trisulfated disaccharide units, IdoA (2S)-GalNAc(4S), IdoA-GalNAc(4S,6S) and IdoA (2S)-GalNAc(4S,6S), where 2S represents 2-O-sulfate. Of the demonstrated sequences, five tetra- and four hexasaccharide sequences containing these units were novel.
authors.affiliation: Department of Biochemistry, Kobe Pharmaceutical University, Japan.
authors.forename: C
authors.initials: C
authors.lastname: Ueoka
authors.forename: S
authors.initials: S
authors.lastname: Nadanaka
authors.forename: N
authors.initials: N
authors.lastname: Seno
authors.forename: K H
authors.initials: KH
authors.lastname: Khoo
authors.forename: K
authors.initials: K
authors.lastname: Sugahara
mesh_terms: D000818:Animals; D002240:Carbohydrate Sequence; D002809:Chondroitin Sulfates / Q000737:chemistry* / Q000302:isolation & purification; D002851:Chromatography, High Pressure Liquid; D006196:Hagfishes / Q000378:metabolism*; D009682:Magnetic Resonance Spectroscopy; D008969:Molecular Sequence Data; D009672:Notochord / Q000737:chemistry; D009844:Oligosaccharides / Q000737:chemistry* / Q000302:isolation & purification; D016339:Spectrometry, Mass, Fast Atom Bombardment; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D009844:Oligosaccharides; D002809:Chondroitin Sulfates