Supramolecular interactions between proteins and bioadhesive nanoparticles

今年，我从事了i)由GroEL和金纳米颗粒(AuNPs)形成的多孔团簇，以及ii)DNA功能化GroEL的橄榄球自组装。在项目I)我确认了团簇的ATPase活性，并通过透射电子显微镜、低温电子显微镜和冷冻-EM断层扫描分析了团簇的多孔性。这一定量方法证实了簇团中有离散数量的GroEL连接AuNP，正如设计的那样。通过客体负载研究，以不同的聚合物-蛋白质杂化物作为客体物种，也探索了多孔性。这表明该星系团可以容纳几十纳米量级的客体，客体流体动力学直径限制在45纳米左右。客体聚合物构象对负荷的影响的实验正在进行中。在项目II)中，我研究了各种核苷酸及其类似物、DNA序列和盐条件在橄榄球形成中的作用。这使人们对增长的重要因素有了全面的了解，并支持拟议的大会机制。我确定了GroEL单元在结构中的排列及其各向异性性质。目前的实验旨在确定该结构是否为中空。

This year I worked on i) porous clusters formed by GroEL and gold nanoparticles (AuNPs), and ii) rugby ball self-assembly of DNA-functionalized GroEL.In project i) I confirmed the ATPase activity of the clusters and analyzed the porous nature of the clusters by TEM, cryo TEM, and cryo-EM tomography. This quantitative approach confirmed that the clusters had discrete numbers of GroEL connecting AuNPs, as designed. The porous nature was also probed by guest loading studies, using various polymer-protein hybrids as guest species. This indicated that the cluster can accommodate guests on the order of several tens of nanometers in size, with a guest hydrodynamic diameter limit of around 45 nm. Experiments on the effect of guest polymer conformation on loading are ongoing.In project ii) I studied the roles of various nucleotides and analogues, DNA sequence, and salt conditions in the rugby ball formation. This gave a complete understanding of the important factors for growth and supported a proposed mechanism for the assembly. I identified the alignment of GroEL units in the structure and its anisotropic nature. Current experiments are targeted to identify whether the structure is hollow.