A triple-binding-domain model explains the specificity of the interaction of a sphingolipid activator protein (SAP-1) with sulphatide, GM1-ganglioside and globotriaosylceramide.
The conformations of the neutral glycosphingolipid, globotriaosylceramide, and of the methyl ester of GM1-ganglioside have been predicted by energy-minimization techniques and compared with those previously obtained for GM1- and GM2-ganglioside. A triple-binding-domain model is put forward to explain known specificities of binding between these glycosphingolipids and activator proteins. This model suggests that hydrophobic interactions, electrostatic interactions and hydrogen-bonding between sugar residues are important. The model is discussed in relation to previous studies on the effect of chemical modification of glycosphingolipids on their ligand properties.
D005677:G(M1) Ganglioside / Q000378:metabolism*; D005915:Globosides / Q000378:metabolism*; D006023:Glycoproteins; D006028:Glycosphingolipids / Q000378:metabolism*; D008958:Models, Molecular; D011487:Protein Conformation; D011506:Proteins / Q000378:metabolism*; D049231:Saposins; D049128:Sphingolipid Activator Proteins; D013433:Sulfoglycosphingolipids / Q000378:metabolism*; D014281:Trihexosylceramides
D005915:Globosides; D006023:Glycoproteins; D006028:Glycosphingolipids; D011506:Proteins; D049231:Saposins; D049128:Sphingolipid Activator Proteins; D013433:Sulfoglycosphingolipids; D014281:Trihexosylceramides; D005677:G(M1) Ganglioside; C018549:globotriaosylceramide