The Partitioning of Small Aromatic Molecules to Air-Water and Phospholipid Interfaces Mediated by Non-Hydrophobic Interactions.
The Partitioning of Small Aromatic Molecules to Air-Water and Phospholipid Interfaces Mediated by Non-Hydrophobic Interactions.
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DOI：
10.1021/acs.jpcb.6b05084
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发表时间：
2016-07
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影响因子：
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通讯作者：
Russell J. Perkins;A. Kukharchuk;P. Delcroix;R. Shoemaker;Martina Roeselová;Lukasz Cwiklik;V. Vaida
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文献类型：
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作者：
Russell J. Perkins;A. Kukharchuk;P. Delcroix;R. Shoemaker;Martina Roeselová;Lukasz Cwiklik;V. Vaida
苯丙氨酸在正常的生物功能和疾病状态如苯丙酮尿症(PKU)和淀粉样原纤维疾病中都有重要作用。苯丙氨酸在生物系统中行为的两个关键方面是它优先分配到膜中和它聚集的倾向。为了考察导致这一行为的分子间相互作用，通过实验和分子动力学模拟研究了一系列与苯丙氨酸结构相关的分子(苯甘氨酸、苯乙酸和酪氨酸)的表面分配行为。测量了芳香族溶液在存在和不存在1，2-dipalmitoyl-sn-glycero-3-phosphatidylcholine(DPPC)单层膜时的表面张力随时间的变化，单层膜起到了简单模型膜的作用。观察到的表面活性趋势与基于溶解度和疏水性的简单预测不符。通过朗缪尔槽、核磁共振、荧光自猝灭和质谱学测量相结合的方法研究了聚集态的可能性。结果表明，这些分子在溶液中不会发生明显的聚集现象，但有可能发生界面聚集现象。根据团簇稳定性和分子构象柔性对观察到的表面活性变化趋势进行了解释。
Phenylalanine has an important role both in normal biological function and in disease states such as phenylketonuria (PKU) and amyloid fibril diseases. Two crucial aspects of phenylalanine behavior in biological systems are its preferential partitioning into membranes and its propensity to cluster. In order to examine the intermolecular interactions that give rise to this behavior, the surface partitioning behavior was investigated for a series of molecules structurally related to phenylalanine (phenylglycine, phenylacetic acid, and tyrosine) both experimentally and by molecular dynamics simulations. Surface tension measurements were performed over time for aromatic solutions both in the presence and in the absence of 1,2-dipalmitoyl-sn-glycero-3-phosphatidylcholine (DPPC) monolayer films, which functioned as simple model membranes. The observed trends in surface activity defy simple predictions based on solubility and hydrophobicity. The possibility of clustering is investigated through a combination of Langmuir trough, nuclear magnetic resonance (NMR), fluorescence self-quenching, and mass spectroscopy measurements. It is concluded that clustering does not occur in solution to a significant extent for these molecules, but interfacial clustering is likely. An explanation for observed trends in surface activity is presented on the basis of cluster stability and molecular conformational flexibility.