title: Extraction and characterization of the tissue forms of collagen types II and IX from bovine vitreous.
abstract: We report for the first time that, after centrifugation of adult bovine vitreous, the hyaluronan-rich supernatant contains collagens which can be isolated in their intact forms by precipitation with 4.5 M NaCl. This precipitate constituted approx. 4% of the total vitreous collagen and comprised collagen types IX and II (in the approximate ratio of 4:1) with negligible amounts of type-V/XI collagen. Type-II collagen was present partly in a pro-alpha 1(II) form, suggesting that there is active synthesis of type-II collagen into the matrix of adult bovine vitreous. Type-IX collagen was purified (2-2.5 mg/l of vitreous) and its glycosaminoglycan chain composition was analysed. Bovine vitreous type-IX collagen always possessed a glycosaminoglycan chain of comparatively low M(r) that was predominantly 4-sulphated, with chondroitin 6-sulphate representing a more minor component. By contrast, chick vitreous has been shown to contain type-IX collagen which always possesses a high-M(r) chondroitin sulphate chain that is predominantly 6-sulphated. The functional significance of these different glycosaminoglycan chain lengths and sulphation patterns is discussed.
authors.affiliation: School of Biological Sciences, University of Manchester, U.K.
authors.forename: P N
authors.initials: PN
authors.lastname: Bishop
authors.forename: M V
authors.initials: MV
authors.lastname: Crossman
authors.forename: D
authors.initials: D
authors.lastname: McLeod
authors.forename: S
authors.initials: S
authors.lastname: Ayad
mesh_terms: D000818:Animals; D015153:Blotting, Western; D002240:Carbohydrate Sequence; D002417:Cattle; D002645:Chickens; D002848:Chromatography, DEAE-Cellulose; D002850:Chromatography, Gel; D003094:Collagen / Q000737:chemistry* / Q000302:isolation & purification*; D004187:Disaccharides / Q000032:analysis / Q000737:chemistry; D004591:Electrophoresis, Polyacrylamide Gel; D006025:Glycosaminoglycans / Q000737:chemistry / Q000302:isolation & purification; D006909:Hydroxyproline / Q000032:analysis; D007202:Indicators and Reagents; D008969:Molecular Sequence Data; D008970:Molecular Weight; D014822:Vitreous Body / Q000737:chemistry*
chemical_list: D004187:Disaccharides; D006025:Glycosaminoglycans; D007202:Indicators and Reagents; D003094:Collagen; D006909:Hydroxyproline