Characterization of sulfated oligosaccharides in mucopolysaccharidosis type IIIA by electrospray ionization mass spectrometry.
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.
Mason
Kerryn E
KE
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.
Meikle
Peter J
PJ
Hopwood
John J
JJ
Fuller
Maria
M
D000818:Animals; D016466:CHO Cells; D002851:Chromatography, High Pressure Liquid; D006224:Cricetinae; D003412:Cricetulus; D009084:Mucopolysaccharidosis III / Q000378:metabolism*; D009844:Oligosaccharides / Q000032:analysis / Q000378:metabolism*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D013431:Sulfates / Q000737:chemistry*
D009844:Oligosaccharides; D013431:Sulfates