Liu Jiajia, Yang Zaixing, Li Haotian, Gu Zonglin, Garate Jose Antonio, Zhou Ruhong
Institute of Quantitative Biology and Medicine, SRMP and RAD-X, Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education Institutions, and Jiangsu Provincial Key Laboratory of Radiation Medicine and Protection, Soochow University, Suzhou 215123, China.
Bio-X Lab, Department of Physics, Zhejiang University, Hangzhou 310027, China.
J Chem Phys. 2014 Dec 14;141(22):22D520. doi: 10.1063/1.4901113.
Clearance of partially ordered oligomers and monomers deposited on cell membrane surfaces is believed to be an effective route to alleviate many potential protein conformational diseases (PCDs). With large-scale all-atom molecular dynamics simulations, here we show that graphene nanosheets can easily and quickly win a competitive adsorption of human islet amyloid polypeptides (hIAPP22-28) NFGAILS and associated fibrils against cell membrane, due to graphene's unique two-dimensional, highly hydrophobic surface with its all-sp(2) hybrid structure. A nanoscale dewetting transition was observed at the interfacial region between the fibril (originally deposited on the membrane) and the graphene nanosheet, which significantly assisted the adsorption of fibrils onto graphene from the membrane. The π-π stacking interaction between Phe23 and graphene played a crucial role, providing the driving force for the adsorption at the graphene surface. This study renders new insight towards the importance of water during the interactions between amyloid peptides, the phospholipidic membrane, and graphene, which might shed some light on future developments of graphene-based nanomedicine for preventing/curing PCDs like type II diabetes mellitus.
清除沉积在细胞膜表面的部分有序寡聚体和单体被认为是缓解许多潜在蛋白质构象疾病（PCD）的有效途径。通过大规模全原子分子动力学模拟，我们在此表明，由于石墨烯独特的二维、高度疏水表面及其全sp(2)杂化结构，石墨烯纳米片可以轻松快速地在与细胞膜的竞争吸附中胜出，吸附人胰岛淀粉样多肽（hIAPP22-28）NFGAILS及其相关纤维。在原沉积在膜上的纤维与石墨烯纳米片的界面区域观察到纳米级的去湿转变，这显著促进了纤维从膜上吸附到石墨烯上。Phe23与石墨烯之间的π-π堆积相互作用起了关键作用，为在石墨烯表面的吸附提供了驱动力。这项研究为淀粉样肽、磷脂膜和石墨烯之间相互作用过程中水的重要性提供了新的见解，这可能为基于石墨烯的纳米医学预防/治疗II型糖尿病等PCD的未来发展提供一些启示。
