PROTEIN SOLVATION IN ALLOSTERIC REGULATION - A WATER EFFECT ON HEMOGLOBIN
PROTEIN SOLVATION IN ALLOSTERIC REGULATION - A WATER EFFECT ON HEMOGLOBIN
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DOI：
10.1126/science.1585178
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发表时间：
1992-05-01
期刊：
影响因子：
56.9
通讯作者：
PARSEGIAN, VA
中科院分区：
文献类型：
--
作者：
COLOMBO, MF;RAU, DC;PARSEGIAN, VA
血红蛋白的氧亲和力随水浴介质中水的化学势线性变化，如从几种中性溶质（即蔗糖、水苏糖和两种聚乙二醇（分子量为150和400））的渗透效应所见。通过Wyman连接方程或Gibbs-Duhem关系分析的数据表明，在从完全脱氧的紧张（T）状态到完全氧合的松弛（R）状态的过渡期间，大约有60个额外的水分子与血红蛋白结合。这个数字与溶质的性质无关，与之前计算的两种构象的水可及表面积的差异一致。溶剂化在变构调节中的作用再也不能被忽视了。
The oxygen affinity of hemoglobin varies linearly with the chemical potential of water in the bathing medium, as seen from the osmotic effect of several neutral solutes, namely sucrose, stachyose, and two polyethyleneglycols (molecular weights of 150 and 400). The data, analyzed either by Wyman linkage equations or by Gibbs-Duhem relations, show that approximately 60 extra water molecules bind to hemoglobin during the transition from the fully deoxygenated tense (T) state to the fully oxygenated relaxed (R) state. This number, independent of the nature of the solute, agrees with the difference in water-accessible surface areas previously computed for the two conformations. The work of solvation in allosteric regulation can no longer go unrecognized.