Dani M, Manca F, Rialdi G
Biochim Biophys Acta. 1981 Jan 30;667(1):108-17. doi: 10.1016/0005-2795(81)90071-4.
The binding of concanavalin A in the dimer form to various saccharides has been studied by calorimetry, and estimates of the binding enthalpy and binding constants have been calculated. Methyl alpha-D-mannoside and methyl alpha-D-glucoside have a -- delta H0 of 21.5 and 11.5 kJ/mol, respectively, at both pH 4 and 4.5. The p-nitrophenyl derivatives react with enthalpic values of 15.6 and 14.6 kJ/mol. The galactosepyranosides show no heat effects during mixing with the protein solutions. The apparent binding enthalpies calculated from the variations of the equilibrium constants with temperature are in good agreement with the values measured experimentally. The two binding sites of the dimer form of concanavalin A are equal and independent, and the low enthalpies obtained do not justify a large conformational change during the reaction. The binding reaction has also been estimated for other sugars normally contained in glycoproteins.
已通过量热法研究了二聚体形式的伴刀豆球蛋白A与各种糖类的结合，并计算了结合焓和结合常数的估计值。在pH 4和4.5时，α-D-甲基甘露糖苷和α-D-甲基葡萄糖苷的ΔH0分别为21.5和11.5 kJ/mol。对硝基苯基衍生物反应的焓值分别为15.6和14.6 kJ/mol。吡喃半乳糖苷与蛋白质溶液混合时无热效应。根据平衡常数随温度的变化计算出的表观结合焓与实验测量值吻合良好。伴刀豆球蛋白A二聚体形式的两个结合位点是等同且独立的，反应过程中获得的低焓值无法证明有大的构象变化。还对糖蛋白中通常含有的其他糖类的结合反应进行了评估。
