PROTEIN STABILIZATION AND DESTABILIZATION BY GUANIDINIUM SALTS
PROTEIN STABILIZATION AND DESTABILIZATION BY GUANIDINIUM SALTS
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DOI：
10.1021/bi00320a005
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发表时间：
1984-01-01
期刊：
影响因子：
2.9
通讯作者：
TIMASHEFF, SN
中科院分区：
文献类型：
--
作者：
ARAKAWA, T;TIMASHEFF, SN
研究了牛血清白蛋白与硫酸胍、乙酸胍和盐酸胍的优先相互作用。结果表明，随着盐浓度的增加，硫酸盐的优先水合作用增加，盐酸盐的正优先盐结合和乙酸盐的中间情况。这些结果与已知的3种盐对蛋白质稳定性的作用，即硫酸胍的稳定作用和盐酸胍的变性作用，有很好的相关性。胍盐和镁盐的比较表明，胍离子取代Mg 2+降低了优先水合和增加优先盐结合，这表明胍离子结合的表面自由能的扰动大于Mg 2+离子。胍盐不是一个特殊的类别，但它们对蛋白质的活性与其他盐一样，受到水合作用和与蛋白质结合的盐之间的精细平衡的调节，第二个因素在胍盐中更强。
Preferential interactions of bovine serum albumin were measured with guanidine sulfate, guanidine acetate and guanidine hydrochloride. The results showed an increasing preferential hydration with increasing salt concentration for the sulfate, positive preferential salt binding for the hydrochloride and an intermediate situation for the acetate. These results correlate well with the known effects of the 3 salts on protein stability, namely, the stabilizing effect of guanidine sulfate and the denaturing effect of guanidine hydrochloride. Comparison of guanidinium and magnesium salts indicated that the substitution of guanidinium ion for Mg2+ decreases the preferential hydration and increases the preferential salt binding, suggesting that the perturbation by guanidinium ion binding of the surface free energy is greater than that by Mg2+ ion. Guanidine salts are not a special class, but their activity toward proteins is modulated by the same fine balance between hydration and salt binding to protein as in the case of other salts, with the second factor being stronger in guanidine salts.