Computer simulations of peptide folding, aggregation, and adsorption to solid substrates

在最近的实验中，可以证明肽与某些固体底物的结合是高度特异性的。它在很大程度上取决于肽的氨基酸序列和吸附材料的性质。吸附过程的主要机理仍不清楚。目前尚不清楚，这一过程是否伴随着肽的再折叠，或者它是否是一个简单的对接过程，没有明显的肽结构变化。目前还不清楚肽在密集溶液中的聚集如何影响吸附强度。人们对理解这种有机-无机杂化系统日益增长的兴趣，可以通过纳米传感和纳米电子器件的未来生物技术应用来解释。在这个项目中，我们首先计划进行蒙特卡罗计算机模拟，以揭示实验中使用的合成序列的单肽折叠特性。在下一步中，将首先研究在没有底物的情况下多肽体系中的聚集。对于这些研究，将采用Lund小组开发的具有简化力场的全原子模型。最终，该模型通过纳入与固体底物的相互作用而得到扩展，并将用于可获得实验数据的杂化肽-硅系统。

In recent experiments it could be shown that the binding of peptides to certain solid substrates is highly specific. It strongly depends on the amino acid sequence of the peptides and the properties of the adsorbing material. The principal mechanisms of the adsorption process are still widely unknown. It is not yet clear, whether this process is accompanied by a refolding of the peptide or whether it is a simple docking process without noticeable structural changes of the peptide. It is also not known how peptide aggregation in dense solutions influences the adsorption strength. The growing interest in understanding such organic-inorganic hybrid systems is explained by possible future biotechnological applications of nanosensory and nanoelectronic devices. In this project we first plan to perform Monte Carlo computer simulations in order to reveal the single-peptide folding properties of the synthetic sequences used in the experiments. In the next step aggregation in multiple-peptide systems at first without substrate shall be investigated. For these studies the all-atom model with reduced force field, developed by the Lund group, shall be employed. Eventually, this model is extended by incorporating the interaction with solid substrates and shall be exploited for hybrid peptide-silicon systems, for which experimental data are available.