A pairwise preferential interaction model (PPIM), based on Kirkwood–Buff integrals, is developed to quantify and characterize the interactions between some of the functional groups commonly observed in peptides. The existing experimental data are analyzed to determine the preferential interaction (PI) parameters for different amino acid and small peptide systems in aqueous solutions. The PIs between the different functional groups present in the peptides are then isolated and quantified by assuming simple pairwise additivity. The PPIM approach provides consistent estimates for the pair interactions between the same functional groups obtained from different solute molecules. Furthermore, these interactions appear to be chemically intuitive. It is argued that this type of approach can provide valuable information concerning specific functional group correlations which could give rise to peptide aggregation.

中文翻译：

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用于理解肽聚集的成对优先相互作用模型

开发了基于 Kirkwood-Buff 积分的成对优先相互作用模型 (PPIM) 来量化和表征肽中常见的一些官能团之间的相互作用。分析现有的实验数据以确定水溶液中不同氨基酸和小肽系统的优先相互作用 (PI) 参数。然后通过假设简单的成对可加性来分离和量化肽中存在的不同官能团之间的 PI。PPIM 方法为从不同溶质分子获得的相同官能团之间的配对相互作用提供了一致的估计。此外，这些相互作用在化学上似乎是直观的。