Mason Kerryn E, Meikle Peter J, Hopwood John J, Fuller Maria
Lysosomal Diseases Research Unit, Department of Genetic Medicine, Children, Youth and Women's Health Service, 72 King William Road, North Adelaide, South Australia, 5006 Australia.
Anal Chem. 2006 Jul 1;78(13):4534-42. doi: 10.1021/ac052083d.
Heparan sulfate is a linear glycosaminoglycan with considerable structural diversity that binds a myriad of growth factors and proteins that play pivotal roles in a variety of biological processes. We have investigated the structural complexity of partially degraded fragments of heparan sulfate in mucopolysaccharidosis type IIIA in which there is a defect in heparan sulfate catabolism. Mono- to hexadecasaccharides were isolated from the urine of a mucopolysaccharidosis IIIA patient and shown to have non-reducing end glucosamine N-sulfate residues, reflecting the catabolic deficiency in heparan N-sulfatase (sulfamidase) activity. The use of nitrous acid digestion (pH 1.5) combined with separation by reverse-phase high-performance liquid chromatography and analysis by electrospray ionization-mass spectrometry identified multiple forms of these oligosaccharides with some N-acetylated glucosamine residues and one to three sulfates per disaccharide. Furthermore, we demonstrated that each oligosaccharide existed in multiple sulfated forms. Many structural isomers were present, suggesting a complex mixture of oligosaccharides present in the urine as a consequence of a defect in heparan sulfate degradation.
硫酸乙酰肝素是一种具有相当结构多样性的线性糖胺聚糖，它能结合多种生长因子和蛋白质，这些因子和蛋白质在多种生物过程中发挥关键作用。我们研究了ⅢA型黏多糖贮积症中硫酸乙酰肝素部分降解片段的结构复杂性，该病存在硫酸乙酰肝素分解代谢缺陷。从一名ⅢA型黏多糖贮积症患者的尿液中分离出单糖至十六糖，并显示其具有非还原端氨基葡萄糖N-硫酸酯残基，这反映了肝素N-硫酸酯酶（硫酸酰胺酶）活性的分解代谢缺陷。使用亚硝酸消化（pH 1.5）结合反相高效液相色谱分离和电喷雾电离质谱分析，鉴定出这些寡糖的多种形式，每个二糖含有一些N-乙酰化氨基葡萄糖残基和一至三个硫酸酯。此外，我们证明每种寡糖都以多种硫酸化形式存在。存在许多结构异构体，这表明由于硫酸乙酰肝素降解缺陷，尿液中存在复杂的寡糖混合物。
