在酶分散中,离子的不对称分割
Pierandrea Lo Nostro1, Niccolò Peruzzi, Mirko Severi
1Department of Chemistry and CSGI, University of Florence, 50019 Sesto Fiorentino, Florence, Italy. pln@csgi.unifi.it
Journal of the American Chemical Society
|April 17, 2010
概括
蛋白质分散与二硫酸盐相分开,形成两个液态相. 电解质会影响相位分离,而蛋白质分散作用就像一个化学海绵,在没有活跃送的情况下将蛋白质集中起来.
科学领域:
- 物理化学 物理化学
- 生物物理化学 生物物理化学
- 体科学 体科学 体科学
背景情况:
- 蛋白质和表面活性剂的水性分散可以表现出复杂的相位行为.
- 了解相位分离对于蛋白质的配方和加工至关重要.
- 霍夫迈斯特系列描述了离子对蛋白质溶解度和相互作用的特异性影响.
研究的目的:
- 为了研究溶酶和二甲硫酸盐 (SDS) 在水溶中的相分离.
- 为了确定电解质对云点温度 (T (c)) 和相位行为的影响.
- 探索离子在共存的液态相之间的分离,以及自我度的潜力.
主要方法:
- 酶和SDS的水溶的制备.
- 在不同的电解质条件下测量云点温度 (T(c)).
- 在分离的液相之间分析离子分离的分析.
- 阶段分离现象的热力学分析.
主要成果:
- 酶-SDS分散阶段在云点以下分为两个液态阶段.
- 在逆霍夫迈斯特序列之后,电解质显著改变T (c).
- 阳离子在两个相之间呈现不对称的分割,这取决于特定的阳离子.
- 缩的蛋白质阶段充当化学海绵,使度差异没有活跃的送.
结论:
- 在蛋白质-表面活性剂系统中,电解质诱导的相分离受特定离子效应 (霍夫迈斯特系列) 的控制.
- 不对称的离子分离驱动形成不同的液相.
- 蛋白质分散可以自发地缩蛋白质,提供一种实现高蛋白质度的被动方法.
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