Lien vers Pubmed [PMID] – 9742688
Carbohydr. Res. 1998 Jul;309(3):219-26
The O-specific polysaccharide (O-SP) of Shigella dysenteriae type 1 has been shown by others to have the structure–>3)-alpha-L-Rhap-(1–>3)-alpha-L-Rhap-(1–>2)-alp ha-D- Galp-(1–>3)-alpha-D-GlcpNAc-(1–>. We have shown in the past that IgM 3707 E9, an anti S. dysenteriae type 1 O-SP monoclonal antibody, binds specifically to the -alpha-L-Rhap-(1–>2)-alpha-D-Galp-determinant of the polysaccharide. In this report we show that determinant to have hydrogen bonds, necessary for binding to the antibody, involving positions 3, 4 and 6 of the galactopyranosyl residue. The hydroxyl groups of the rhamnopyranosyl moiety of the immunodeterminant appear not to partake in hydrogen-bond interactions with the antibody. A model is presented of the Fv of IgM 3707 E9 based on our previously established cDNA-sequence and two known, highly homologous immunoglobulin crystal structures. The methyl glycoside of the immunodeterminant alpha-L-rhamnopyranosyl-(1–>2)-alpha-D-galactopyranose is docked to the combining area of the Fv.