Functional groups of sialic acids involved in binding to siglecs (sialoadhesins) deduced from interactions with synthetic analogues
The siglecs, formerly called sialoadhesins, are a family of I-type lectins binding to sialic acids on the cell surface. Five members of this family have been identified : sialoadhesin, myelin-associated glycoprotein (MAG), Schwann cell myelin protein (SMP), CD22 and CD33. We have investigated the re...
Saved in:
| Main Authors: | , , , , , |
|---|---|
| Format: | Article (Journal) |
| Language: | English |
| Published: |
August 1998
|
| In: |
EJB
Year: 1998, Volume: 255, Issue: 3, Pages: 663-672 |
| ISSN: | 1432-1033 |
| DOI: | 10.1046/j.1432-1327.1998.2550663.x |
| Online Access: | Verlag, lizenzpflichtig, Volltext: https://doi.org/10.1046/j.1432-1327.1998.2550663.x Verlag, lizenzpflichtig, Volltext: https://onlinelibrary.wiley.com/doi/abs/10.1046/j.1432-1327.1998.2550663.x 
|
| Author Notes: | Sørge Kelm, Reinhard Brossmer, Rainer Isecke, Hans-Jürgen Gross, Karen Strenge, Roland Schauer |
| Summary: | The siglecs, formerly called sialoadhesins, are a family of I-type lectins binding to sialic acids on the cell surface. Five members of this family have been identified : sialoadhesin, myelin-associated glycoprotein (MAG), Schwann cell myelin protein (SMP), CD22 and CD33. We have investigated the relevance of substituents at position C-9 and in the N-acetyl group of N-acetylneuraminic acid, using a series of synthetic sialic-acid analogues either on resialylated human erythrocytes or as free α-glycosides in hapten inhibition. All five siglecs require the hydroxy group at C-9 for binding, suggesting hydrogen bonding of this substituent with the binding site. Remarkable differences were found among the proteins in their specificity for modifications of the N-acetyl group. Whereas sialoadhesin, MAG and SMP do not tolerate a hydroxy group as in N-glycolylneuraminic acid, they bind to halogenated acetyl residues. In the case of MAG, N-fluoroacetylneuraminic acid is bound about 17-fold better than N-acetylneuraminic acid. In contrast, human and murine CD22 both show good affinity for N-glycolylneuraminic acid, but only human CD22 bound the halogenated compounds. In conclusion, our data indicate that interactions of the hydroxy group at position 9 and the N-acyl substituent contribute significantly to the binding strength. |
|---|---|
| Item Description: | Elektronische Reproduktion der Druck-Ausgabe 25. Dezember 2001 Gesehen am 26.06.2024 |
| Physical Description: | Online Resource |
| ISSN: | 1432-1033 |
| DOI: | 10.1046/j.1432-1327.1998.2550663.x |