Protein-carbohydrate interaction. IV. Application of the quantitative precipitin method to polysaccharide-concanavalin A interaction.
Protein-carbohydrate interaction. IV. Application of the quantitative precipitin method to polysaccharide-concanavalin A interaction.
复制标题
蛋白质-碳水化合物相互作用。
DOI：
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发表时间：
1967
影响因子：
4.8
通讯作者：
I. Goldstein
中科院分区：
文献类型：
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作者：
L. L. So;I. Goldstein
摘要伴刀豆球蛋白A是在刀豆中发现的一种球蛋白，它与一组限制性的支链多糖发生特异性反应形成沉淀。这种相互作用的最佳的各种参数进行了研究，通过定量沉淀法与葡聚糖作为沉淀多糖。以这种方式，建立了伴刀豆球蛋白A活性的测定。这种相互作用与抗体-抗原系统的相似性是惊人的。调查结果摘要如下。1.在25° C下24小时内实现完全沉淀。2.反应的最佳pH范围为6.1至7.2。3.当体系用磷酸盐缓冲至pH 7.0时，氯化钠的浓度对反应没有影响。然而，KI和KCNS是抑制性的。4.外源蛋白的存在不影响伴刀豆球蛋白A沉淀的总量。5.伴刀豆球蛋白A和葡聚糖之间形成的沉淀物在25° C下微溶（每毫升1.5 µg氮）。6.在25°下比在0°下沉淀更多的氮，相对量取决于所检查的当量曲线的区域。
Abstract Concanavalin A, a globulin found in the jack bean, reacts specifically to form a precipitate with a restricted group of branched polysaccharides. The various parameters optimal for this interaction were investigated by the quantitative precipitin method with a dextran as the precipitating polysaccharide. In this manner, an assay for concanavalin A activity was established. The analogy of this interaction with the antibody-antigen system is striking. A summary of findings follows. 1. Complete precipitation is achieved in 24 hours at 25°. 2. The pH range optimum for the reaction lies between 6.1 and 7.2. 3. The concentration of sodium chloride has no effect on the reaction when the system is buffered at pH 7.0 with phosphate. KI and KCNS, however, are inhibitory. 4. The presence of foreign proteins does not affect the total amount of concanavalin A precipitated. 5. The precipitate formed between concanavalin A and dextran is slightly soluble (1.5 µg of nitrogen per ml) at 25°. 6. More nitrogen is precipitated at 25° than at 0°, the relative amount depending upon the region of the equivalence curve examined.