AbstractThe lack of new antibiotics and the rapidly rising number of pathogens resistant to antibiotics pose a serious problem to mankind. In bacteria, the cell membrane provides the first line of defence to antibiotics by preventing them from reaching their molecular target. To overcome this entrance barrier, it has been suggested[1] that small Gold‐Nanoparticles (AuNP) could possibly function as drug delivery systems for antibiotic ligands. Using actinonin‐based ligands, we provide here proof‐of‐principle of AuNP functionalisation, the capability to bind and inhibit the target protein of the ligand, and the possibility to selectively release the antimicrobial payload. To this end, we successfully synthesised AuNP coated with thio‐functionalised actinonin and a derivative. Interactions between 15N‐enriched His‐peptide deformylase 1–147 from E. coli (His‐ecPDF 1–147) and compound‐coated AuNP were investigated via 2D 1H‐15N‐HSQC NMR spectra proving the direct binding to His‐ecPDF 1–147. More importantly by adding dithiothreitol (DTT), we show that the derivative is successfully released from AuNPs while still bound to His‐ecPDF 1–147. Our findings indicate that AuNP‐conjugated ligands can address and bind intracellular target proteins. The system introduced here presents a new delivery platform for antibiotics and allows for the easy optimisation of ligand coated AuNPs.
摘要 新型抗生素的缺乏和对抗生素产生抗药性的病原体数量的迅速增加给人类带来了严重的问题。在细菌体内,细胞膜是抗生素的第一道防线,它阻止抗生素到达其分子目标。为了克服这一入口障碍,有人提出[1] 小型金纳米粒子(AuNP)有可能成为抗生素配体的药物输送系统。利用基于肌动蛋白的配体,我们在此提供了 AuNP 功能化的原理验证,证明了其结合和抑制配体靶蛋白的能力,以及选择性释放抗菌载荷的可能性。为此,我们成功合成了涂有硫代功能化肌动蛋白及其衍生物的 AuNP。我们通过二维 1H-15N-HSQC NMR 光谱研究了大肠杆菌中富含 15N 的 His 肽变形酶 1-147(His-ecPDF 1-147)与化合物包覆的 AuNP 之间的相互作用,证明其与 His-ecPDF 1-147 直接结合。更重要的是,通过添加二硫苏糖醇(DTT),我们发现该衍生物在与 His-ecPDF 1-147 结合的同时成功地从 AuNPs 中释放出来。我们的研究结果表明,与 AuNP 结合的配体可以处理并结合细胞内的靶蛋白。这里介绍的系统为抗生素提供了一个新的递送平台,并可轻松优化配体包覆的 AuNPs。