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葡萄果实微粒体上存在高亲和力的脱落酸（ＡＢＡ）结合位点，这些位点与ＡＢＡ的结合具有饱和性，高亲和力及低容量，胰蛋白酶或ＤＴＴ处理可以使该位点的特异结合活性下降约９０％，表明此结合位点是一种蛋白质，故称为ＡＢＡ结合蛋白，它含有维系蛋白质特定构象的二硫键，该蛋白与ＡＢＡ反应的最适ｐＨ为６．０，说明与配基结合部位可能存在带有正电荷的氨基酸残基，结合活性在２５℃高于０℃，结合反应达到动态平衡需要３０ｍｉｎ，３０ｍｉｎ以后结合活性随时间延长而下降。该蛋白与ＡＢＡ结合反应的平衡解离常数为１７．５ｎｍｏｌ／Ｌ，最大结合容量（Ｂｍａｘ）为９８．４ｆｍｏｌ／ｍｇｐｒｏｔｅｉｎ。
Grape fruit microsomes have high affinity abscisic acid (ABA) binding sites. These sites have saturation, high affinity and low capacity for binding to ABA. Trypsin or DTT treatment can decrease the specific binding activity of this site About 90%, indicating that the binding site is a protein, it is called ABA binding protein, which contains a specific conformation of the protein disulfide bond, the optimal reaction of the protein and ABA pH 6.0, indicating that ligand The binding site may have positively charged amino acid residues. The binding activity is higher than 0 ° C at 25 ° C, and the binding reaction needs to reach the homeostasis for 30 min. After 30 min, the binding activity decreases with time. The equilibrium dissociation constant of this protein with ABA binding was 17.5nmol / L and the maximum binding capacity (Bmax) was 98.4fmol / mgprotein.