Sugar-lectin interactions: how does wheat-germ agglutinin bind sialoglycoconjugates?
The specific binding of N-acetylneuraminic acid to wheat-germ agglutinin is based on configuration similarities between N-acetylneuraminic acid and N-acetylglucosamine. The N-acetamido group and an adjacent hydroxyl group, both in an equatorial position are shown to be the main determinants. The N-acetylneuraminic acid--wheat-germ agglutinin interaction is increased by the removal of the last two carbons C8 and C9. The interaction between wheat-germ agglutinin and glycoconjugates containing N-acetylneuraminic acid is shown to be dependent on a charge effect and on an avidity effect. Succinylated wheat-germ agglutinin which is negatively charged at physiological pH, in contrast with wheat-germ agglutinin which is positively charged, does not bind cell surface glycoconjugates containing N-acetylneuraminic acid but does bind cell surface glycoconjugates containing N-acetylglucosamine. The use of wheat-germ agglutinin and of succinylated wheat-germ agglutinin leads to the determination of the number of cell surface receptors containing N-acetylneuraminic acid.
D000117:Acetylglucosamine; D000818:Animals; D002236:Carbohydrate Conformation; D002241:Carbohydrates; D002460:Cell Line; D055598:Chemical Phenomena; D002621:Chemistry; D006224:Cricetinae; D005732:Gangliosides; D005944:Glucosamine / Q000031:analogs & derivatives; D007668:Kidney; D007700:Kinetics; D037102:Lectins; D009439:Neuraminidase; D012794:Sialic Acids; D013329:Structure-Activity Relationship; D014909:Wheat Germ Agglutinins
D002241:Carbohydrates; D005732:Gangliosides; D037102:Lectins; D012794:Sialic Acids; D014909:Wheat Germ Agglutinins; D009439:Neuraminidase; D005944:Glucosamine; D000117:Acetylglucosamine