Title : Structural study of
the oligosaccharide moieties of sphingolipid activator
proteins , saposins A, C and D obtained from the spleen of a Gaucher patient
Abstract :
- We have determined and compared the structures of the oligosaccharide moieties of saposin A , C and D purified from the spleen of a patient with Gaucher disease
- These saposins, together with saposin B , are small glycoproteins , derived from separate domains of a single precursor , prosaposin , and are required for the lysosomal hydrolysis of various sphingolipids
- The characteristic features of the oligosaccharide moieties of saposin A are (a) the predominance of a fucosylated trimannosyl core structure and (b) the occurrence of several different oligomannose-type and N-acetyllactosamine-type oligosaccharides
- Saposin C contains (a) a predominance of oligomannose-type oligosaccharides and monoantennary oligosaccharides and (b) the presence of four different oligosaccharides having bisecting N-acetylglucosamine residues (found only in this saposin )
- Saposin D is distinguished by the occurrence of oligomannose-type oligosaccharides , which comprise nearly 90% of its total oligosaccharides
- The possible reasons for the unique glycosylation of each saposin is discussed