Theoretical study for partial molar volume of amino acids and polypeptides by the three-dimensional reference interaction site model
Theoretical study for partial molar volume of amino acids and polypeptides by the three-dimensional reference interaction site model
复制标题
DOI：
10.1063/1.1369138
复制
发表时间：
2001-06-01
影响因子：
4.4
通讯作者：
Hirata, F
中科院分区：
文献类型：
--
作者：
Harano, Y;Imai, T;Hirata, F
利用Kirkwood-Buff方程和分子液体三维参考相互作用位点模型（3D-RISM）积分方程理论，计算了20种氨基酸在无限稀释水溶液中的偏摩尔体积（PMV）。与传统的一维（1D-RISM）方法相比，结果显示出与实验定量一致的显著改善。对于较大的氨基酸，与实验数据的偏差是根据前面基于1D-RISM的研究中引入的“理想波动体积”来讨论的。将该方法应用于水溶液中聚谷氨酸的PMV，进一步证明了该方法的鲁棒性。该方法为α -螺旋结构和延伸结构的PMV随链长而增加提供了合理的解释，而1D-RISM方法则为α -螺旋结构提供了非自然的PMV减少，而主链完全旋转。(C) 2001年美国物理研究所。
We calculate the partial molar volume (PMV) of 20 amino acids in aqueous solution at infinite dilution by using the Kirkwood-Buff equation and the three-dimensional reference interaction site model (3D-RISM) integral equation theory for molecular liquids. As compared to the conventional, one-dimensional (1D-RISM) approach, the results exhibit drastic improvement for the quantitative agreement with experiments. The deviation from the experimental data seen for the relatively large amino acids is discussed in terms of the "ideal fluctuation volume" introduced in the previous study based on the 1D-RISM. Robustness of the new approach is further demonstrated by applying it to the PMV of polyglutamic acids in aqueous solution. The method provides reasonable account for the PMV increase with the chain length, both in alpha -helical and extended structures, whereas the 1D-RISM approach gives an unnatural decrease of the PMV for the alpha helix with a complete turn of the backbone. (C) 2001 American Institute of Physics.