Relative affinities of bovine brain 14 kDa galactose lectin binding to individual endogenous gangliosides.
Sugar-specific binding of bovine brain 14 kDa galactose-binding lectin (BBL) to individual endogenous gangliosides (GM1, GM2, GD1a, GD1b and GT1b) was studied using affinity electrophoresis of ganglioside-lectin mixture in polyacrylamide gel at pH 8.3. Unbound (free) lectin moved ahead while ganglioside-lectin complex moved very little. Sugar-specificity of binding was confirmed by reversal of the interaction by (i) presence of lactose along with the lectin and (ii) pretreatment of gangliosides with another galactose-binding lectin, Ricinus communis agglutinin. Stoichiometry of ganglioside-BBL interaction revealed that GT1b had the highest affinity for the lectin followed by GD1b and GM2, while GM1 and GD1a had the least affinity. Results indicated that a terminal sialic acid moiety covering a galactose moiety may at times enhance BBL recognition of the latter and that changes in ganglioside pattern is a possible modulator of lectin function in vivo.
Kannan
V M
VM
Biochemistry Division, Sree Chitra Tirunal Institute for Medical Sciences & Technology, Thiruvananthapuram, India.
Appukuttan
P S
PS
D000818:Animals; D001667:Binding, Competitive; D001921:Brain / Q000378:metabolism; D002417:Cattle; D004591:Electrophoresis, Polyacrylamide Gel; D037161:Galectins; D005732:Gangliosides / Q000737:chemistry / Q000378:metabolism*; D006388:Hemagglutinins / Q000378:metabolism*; D007785:Lactose / Q000378:metabolism / Q000494:pharmacology; D037102:Lectins / Q000378:metabolism; D019158:N-Acetylneuraminic Acid / Q000378:metabolism; D037121:Plant Lectins
D037161:Galectins; D005732:Gangliosides; D006388:Hemagglutinins; D037102:Lectins; D037121:Plant Lectins; C017707:Ricinus communis agglutinin-1; D019158:N-Acetylneuraminic Acid; D007785:Lactose