Conformational Transition of Poly(L-glutamic acid) in Aqueous Decylammonium Chloride Solution
Conformational Transition of Poly(L-glutamic acid) in Aqueous Decylammonium Chloride Solution
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聚（L-谷氨酸）在十烷基氯化铵水溶液中的构象转变
DOI：
10.1246/bcsj.52.361
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发表时间：
1979
影响因子：
4
通讯作者：
H. Kimizuka
中科院分区：
文献类型：
--
作者：
I. Satake;T. Gondo;H. Kimizuka
通过电位测量 pH 7.9 下的结合等温线研究了十烷基氯化铵与聚（L-谷氨酸）（PLG）的协同结合。还测量了圆二色光谱作为表面活性剂离子 (x) 结合程度的函数。结果表明，PLG-表面活性剂复合物的螺旋向α-螺旋的转变随着x的变化而发生。 PLG 在 x 低于 0.55 的范围内没有发生明显的构象变化。但随着x的进一步增加，螺旋含量突然增加。 PLG-表面活性剂复合物螺旋含量的突然增加可以用结合的表面活性剂离子之间的疏水相互作用来很好地解释。基于协同结合等温线的理论分析，得出结论：表面活性剂诱导的螺旋结构的稳定需要形成由至少八个表面活性剂离子组成的胶束状簇。
The cooperative binding of decylammonium chloride to poly(L-glutamic acid) (PLG) was studied by the potentiometric measurement of the binding isotherm at pH 7.9. Circular dichroism spectra were also measured as a function of the degree of binding of surfactant ion (x). It was shown that the coil to α-helix transition of PLG-surfactant complex takes place with a change in x. PLG did not undergo an appreciable conformational change in the range of x below 0.55. But the helical content increased suddenly with further increase in x. An abrupt increase in the helical content of PLG-surfactant complex can be well interpreted in terms of the hydrophobic interaction among bound surfactant ions. On the basis of the theoretical analysis of the cooperative binding isotherm, it was concluded that the formation of a micelle-like cluster consisting of at least eight surfactant ions is required for the stabilization of a surfactant induced helical structure.