Magalhães Pedro R, Machuqueiro Miguel, Baptista António M
Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Oeiras, Portugal.
Centro de Química e Bioquímica and Departamento de Química e Bioquímica, Faculdade de Ciências, Universidade de Lisboa, Lisbon, Portugal.
Biophys J. 2015 May 5;108(9):2282-90. doi: 10.1016/j.bpj.2015.03.052.
To our knowledge, we present the first constant-pH molecular dynamics study of the neuropeptide kyotorphin in the presence of an explicit lipid bilayer. The overall conformation freedom of the peptide was found to be affected by the interaction with the membrane, in accordance with previous results using different methodologies. Analysis of the interactions between the N-terminus amine group of the peptide and several lipid atoms shows that the membrane is able to stabilize both ionized and neutral forms of kyotorphin, resulting in a pKa value that is similar to the one obtained in water. This illustrates how a detailed molecular model of the membrane leads to rather different results than would be expected from simply regarding it as a low-dielectric slab.
据我们所知，我们首次在存在明确脂质双层的情况下对神经肽京都啡肽进行了恒pH分子动力学研究。与使用不同方法的先前结果一致，发现该肽的整体构象自由度受与膜相互作用的影响。对该肽N端胺基与几个脂质原子之间相互作用的分析表明，膜能够稳定京都啡肽的离子化形式和中性形式，从而产生与在水中获得的pKa值相似的pKa值。这说明了膜的详细分子模型如何导致与简单地将其视为低介电平板所预期的结果截然不同的结果。
