The dynamical behavior of hydrated glutathione: a model for protein-water interactions.
The dynamical behavior of hydrated glutathione: a model for protein-water interactions.
复制标题
水合谷胱甘肽的动力学行为：蛋白质-水相互作用的模型。
DOI：
10.1039/c003493b
复制
发表时间：
2010
期刊：
影响因子：
--
通讯作者：
J. Colmenero
中科院分区：
文献类型：
--
作者：
S. Pagnotta;S. Cerveny;Á. Alegría;J. Colmenero
三肽谷胱甘肽作为一个很好的模型蛋白质-水相互作用的可靠性进行了测试，通过宽带介电谱。在具有不同水含量的水溶液上进行的测量显示出令人惊讶的丰富的弛豫图，其非常类似于对于更复杂的蛋白质大分子所观察到的弛豫图。与通常观察到的具有相似分子量的亲水性化合物的溶液不同，检测到至少两种与水相关的过程的存在。较快的一个是对称的，具有阿仑尼乌斯温度依赖性，活化能E（A）= 0.45 +/- 0.05 eV，并归因于水偶极子重新取向。较慢的一个经历了一个明确的动态变化，从一个非Arrhenius的Arrhenius温度依赖性时，交叉的量热玻璃化转变温度的解决方案从高到低的值。这最后一个过程被认为是由于强水合谷胱甘肽组分的动力学，如羧基或胺基。
The reliability of tripeptide glutathione as an excellent model for protein-water interactions is tested by means of broadband dielectric spectroscopy. Measurements performed on aqueous solutions with different water contents show a surprisingly rich relaxation map that strongly resembles those observed for more complex protein macromolecules. At variance with what is normally observed for solutions of hydrophilic compounds with similar molecular weights, the presence of at least two water-related processes is detected. The faster one is symmetric, has an Arrhenius temperature dependence with an activation energy E(A) = 0.45 +/- 0.05 eV and is attributed to water dipole reorientation. The slower one undergoes a clear dynamical change from a non-Arrhenius to an Arrhenius temperature dependence when crossing the calorimetric glass transition temperature of the solution from high to low values. This last process is proposed to be due to the dynamics of strongly-hydrated glutathione components, such as carboxyl or aminic groups.