title: Identification of keratan sulfate disaccharide at C-3 position of glucuronate of chondroitin sulfate from Mactra chinensis.
abstract: Glycosaminoglycans (GAGs), including chondroitin sulfate (CS), dermatan sulfate, heparin, heparan sulfate and keratan sulfate (KS) are linear sulfated repeating disaccharide sequences containing hexosamine and uronic acid [or galactose (Gal) in the case of KS]. Among the GAGs, CS shows structural variations, such as sulfation patterns and fucosylation, which are responsible for their physiological functions through CS interaction with CS-binding proteins. Here, we solved the structure of KS-branched CS-E derived from a clam, Mactra chinensis KS disaccharide [d-GlcNAc6S-(1→3)-β-d-Gal-(1→] was attached to the C-3 position of GlcA, and consecutive KS-branched disaccharide sequences were found in a CS chain. KS-branched polysaccharides clearly exhibited resistance to degradation by chondroitinase ABC or ACII (at low concentrations) compared with typical CS structures. Furthermore, KS-branched polysaccharides stimulated neurite outgrowth of hippocampal neurons. These results strongly suggest that M. chinensis is a rich source of KS-branched CS, and it has important biological activities.
authors.affiliation: Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Japan.
authors.forename: Kyohei
authors.initials: K
authors.lastname: Higashi
authors.affiliation: Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Japan.
authors.forename: Keita
authors.initials: K
authors.lastname: Takeda
authors.affiliation: Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Japan.
authors.forename: Ann
authors.initials: A
authors.lastname: Mukuno
authors.affiliation: Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Japan.
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Okamoto
authors.affiliation: Department of Biology, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, 110 8th Street Troy, NY 12180, U.S.A.
authors.forename: Sayaka
authors.initials: S
authors.lastname: Masuko
authors.affiliation: Department of Biology, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, 110 8th Street Troy, NY 12180, U.S.A.
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Linhardt
authors.affiliation: Graduate School of Pharmaceutical Sciences, Chiba University, 1-8-1 Inohana, Chuo-ku, Chiba 260-8675, Japan.
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Toida
mesh_terms: D000818:Animals; D049872:Bivalvia / Q000737:chemistry* / Q000187:drug effects; D002809:Chondroitin Sulfates / Q000737:chemistry* / Q000494:pharmacology; D002851:Chromatography, High Pressure Liquid; D020723:Glucuronic Acid / Q000737:chemistry*; D006624:Hippocampus / Q000166:cytology; D007632:Keratan Sulfate / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D016501:Neurites / Q000187:drug effects; D011134:Polysaccharides / Q000737:chemistry
chemical_list: D011134:Polysaccharides; D020723:Glucuronic Acid; D002809:Chondroitin Sulfates; D007632:Keratan Sulfate
keywords: Glycobiology; chondroitin sulfate; chondroitinase; keratan sulfate; proteoglycan