THERMODYNAMICS OF BINDING OF BIOTIN AND SOME ANALOGUES BY AVIDIN
THERMODYNAMICS OF BINDING OF BIOTIN AND SOME ANALOGUES BY AVIDIN
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DOI：
10.1042/bj1010774
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发表时间：
1966-01-01
影响因子：
4.1
通讯作者：
GREEN, NM
中科院分区：
文献类型：
--
作者：
GREEN, NM
1. 亲和素与生物素的反应为放热反应，δ δ为-20.3kcal。/摩尔生物素结合。链霉亲和素对应的δ tah值为-23kcal./mol。2. 产生的热量与pH值（在5到9之间）、缓冲液（硼酸盐或氨）以及亲和素与生物素的分数饱和度无关。3. 该反应的熵变为零，表明由于疏水相互作用导致的熵增加被埋埋氢键形成带来的熵减少所抵消。4. 对咪唑酮环上潜在的氢键位点进行修饰，使反应的热输出减小，反应熵为正。
1. The reaction between avidin and biotin was found to be exothermic, DeltaH being -20.3kcal./mole of biotin bound. The corresponding value of DeltaH for streptavidin was -23kcal./mole. 2. The heat evolved was independent of the pH (between 5 and 9), of the buffer (borate or ammonia) and of the fractional saturation of the avidin with biotin. 3. The entropy change for the reaction was zero, and it is suggested that the entropy increase to be expected from hydrophobic interactions was counterbalanced by a decrease in entropy accompanying the formation of buried hydrogen bonds. 4. Modification of the potential hydrogen-bonding sites of the imidazolidone ring led to a decreased heat output and a positive entropy of reaction.