A predominantly hydrophobic recognition of H-antigenic sugars by winged bean acidic lectin: a thermodynamic study.
The thermodynamics of binding of winged bean (Psophocarpus tetragonolobus) acidic agglutinin to the H-antigenic oligosaccharide (Fucalpha1-2Galbeta1-4GlcNAc-oMe) and its deoxy and methoxy congeners were determined by isothermal titration calorimetry. We report a relatively hydrophobically driven binding of winged bean acidic agglutinin to the congeners of the above sugar. This conclusion is arrived, from the binding parameters of the fucosyl congeners, the nature of the enthalpy-entropy compensation plots and the temperature dependence of binding enthalpies of some of the congeners. Thus, the binding site of winged bean acidic agglutinin must be quite extended to accommodate the trisaccharide, with non-polar loci that recognize the fucosyl moiety of the H-antigenic determinant.
Srinivas
V R
VR
Molecular Biophysics Unit, Indian Institute of Science, Bangalore.
Bhanuprakash Reddy
G
G
Surolia
A
A
D000017:ABO Blood-Group System / Q000737:chemistry / Q000378:metabolism*; D002151:Calorimetry; D002236:Carbohydrate Conformation; D050260:Carbohydrate Metabolism; D037102:Lectins / Q000378:metabolism*; D037121:Plant Lectins; D013816:Thermodynamics
D000017:ABO Blood-Group System; C102547:H1 blood group antigen; D037102:Lectins; D037121:Plant Lectins; C049304:winged bean lectin