title: Domain structure of chondroitin sulfate E octasaccharides binding to type V collagen.
abstract: We demonstrated previously that chondroitin sulfate E (ChS-E) binds to type V collagen (Munakata, H., Takagaki, K., Majima, M., and Endo, M. (1999) Glycobiology 9, 1023--1027). In this study, we investigated the structure and binding of ChS-E oligosaccharides. Eleven oligosaccharides were isolated from ChS-E by gel filtration chromatography and anion-exchange high performance liquid chromatography after hydrolysis with testicular hyaluronidase. Separately, seven oligosaccharides were custom synthesized using the transglycosylation reaction of testicular hyaluronidase. Structural analysis was performed by enzymatic digestions in conjunction with high performance liquid chromatography and mass spectrometry. This library of 18 oligosaccharides was used as a source of model molecules to clarify the structural requirements for binding to type V collagen. Binding was analyzed by a biosensor based on surface plasmon resonance. The results indicated that to bind to type V collagen the oligosaccharides must have the following carbohydrate structures: 1) octasaccharide or larger in size; 2) a continuous sequence of three GlcAbeta1--3GalNAc(4S,6S) units; 3) a GlcAbeta1--3GalNAc(4S,6S) unit, GlcAbeta1--3GalNAc(4S) unit or GlcAbeta1--3GalNAc(6S) unit at the reducing terminal; 4) a GlcAbeta1--3GalNAc(4S,6S) unit at the nonreducing terminal. It is likely that these characteristic oligosaccharide sequences play key roles in cell adhesion and extracellular matrix assembly.
authors.affiliation: Department of Biochemistry, Hirosaki University School of Medicine, 5 Zaifu-cho, Hirosaki 036-8562, Japan.
authors.forename: Keiichi
authors.initials: K
authors.lastname: Takagaki
authors.forename: Hidekazu
authors.initials: H
authors.lastname: Munakata
authors.forename: Ikuko
authors.initials: I
authors.lastname: Kakizaki
authors.forename: Mito
authors.initials: M
authors.lastname: Iwafune
authors.forename: Taito
authors.initials: T
authors.lastname: Itabashi
authors.forename: Masahiko
authors.initials: M
authors.lastname: Endo
mesh_terms: D001665:Binding Sites; D002240:Carbohydrate Sequence; D002809:Chondroitin Sulfates / Q000737:chemistry* / Q000378:metabolism; D024141:Collagen Type IV / Q000378:metabolism*; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000138:chemical synthesis / Q000737:chemistry* / Q000378:metabolism
chemical_list: D024141:Collagen Type IV; D009844:Oligosaccharides; C038142:chondroitin sulfate glycosaminoglycan; D002809:Chondroitin Sulfates