Ferreira André F, Rai Akhilesh, Ferreira Lino, Simões Pedro N
Department of Chemical Engineering, CIEPQPF, University of Coimbra, 3030-790, Coimbra, Portugal.
CNC-Center for Neurosciences and Cell Biology, University of Coimbra, 3004-517, Coimbra, Portugal.
Eur Biophys J. 2017 Apr;46(3):247-256. doi: 10.1007/s00249-016-1160-z. Epub 2016 Jul 28.
The immobilization of gold nanoparticles (AuNPs) with antimicrobial peptides (AMPs) is a new and promising way to enhance both the activity and targeting capabilities of AMPs. However, a full understanding of the adsorption process underlying these materials is still lacking. Cecropin-melittin is a peptide with a broad antimicrobial activity while displaying low hemolytic properties, whose conjugation with AuNPs has not been studied before. In this context, we report the investigation of the adsorption process of the cecropin-melittin peptide, with (CM-SH) and without (CM) cysteine at its C-terminus, onto a gold surface based on all-atom MD simulations. Our results show that the way the peptides approach the surface dictates the final conformation and the time required to achieve it in both CM-SH and CM cases. Most important, it is demonstrated that the presence of cysteine promotes a faster conformational stabilization during the lockdown regime of the CM-SH peptide, noticeably affecting this by acting as a preferential anchoring point. This investigation represents a first step in rationalizing, with atomistic detail, some experimentally observed features of CM-SH and CM immobilized gold nanoparticles.
用抗菌肽（AMPs）固定金纳米颗粒（AuNPs）是增强AMPs活性和靶向能力的一种新的且有前景的方法。然而，对于这些材料背后的吸附过程仍缺乏全面的了解。天蚕素 - 蜂毒肽是一种具有广泛抗菌活性且溶血特性低的肽，其与AuNPs的缀合此前尚未被研究。在此背景下，我们基于全原子分子动力学模拟报告了对在其C末端有（CM - SH）和没有（CM）半胱氨酸的天蚕素 - 蜂毒肽在金表面的吸附过程的研究。我们的结果表明，肽接近表面的方式决定了CM - SH和CM两种情况下的最终构象以及达到该构象所需的时间。最重要的是，证明了半胱氨酸的存在促进了CM - SH肽锁定阶段更快的构象稳定，通过作为优先锚定点对其产生显著影响。这项研究代表了在原子细节上合理化CM - SH和CM固定化金纳米颗粒的一些实验观察到的特征的第一步。
