Keratan sulphate in the interglobular domain has a microstructure that is distinct from keratan sulphate elsewhere on pig aggrecan

• Published in: Matrix biology 2009, Vol.28 (1), p.53-61
• Main Authors: Fosang, A.J., Last, K., Poon, C.J., Plaas, A.H.
• Format: Article
• Language: English
• Subjects: Aggrecan; Aggrecans - chemistry; Aggrecans - isolation & purification; Amino Acid Sequence; Animals; Cartilage; Conserved Sequence; Glycosaminoglycans; Humans; Keratan Sulfate - chemistry; Keratan Sulfate - metabolism; Keratan sulphate; Molecular Sequence Data; Peptide Fragments - isolation & purification; Peptide Fragments - metabolism; Protein Structure, Tertiary; Sequence Alignment; Swine
• ISSN: 0945-053X; 1569-1802
• DOI: 10.1016/j.matbio.2008.11.001

The microstructure of keratan sulphate purified from the interglobular domain, the keratan sulphate-rich region and total aggrecan was compared using fluorophore-assisted-carbohydrate-electrophoresis. Keratan sulphate in the interglobular domain was substantially less sulphated than keratan sulphate elsewhere on aggrecan, based on the ratio of unsulphated: monosulphated disaccharides generated by endo-β-galactosidase digestion, and the ratio of monosulphated: disulphated disaccharides generated by keratanase II digestion. The ratio of unsulphated: monosulphated: disulphated disaccharides was 1:4:5 for keratan sulphate from total aggrecan and the keratan sulphate-rich region, but only 1:0.9:0.8 for the interglobular domain. These results show that keratan sulphate in the interglobular domain of pig aggrecan has a microstructure that is distinct from keratan sulphate in the keratan sulphate-rich region.