Nanoscale Physics Research Laboratory, School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT, UK.
Nanotechnology. 2016 Nov 18;27(46):46LT02. doi: 10.1088/0957-4484/27/46/46LT02. Epub 2016 Oct 13.
As the major iron storage protein, ferritin stores and releases iron for maintaining the balance of iron in fauna, flora, and bacteria. We present an investigation of the morphology and iron loading of ferritin (from equine spleen) using aberration-corrected high angle annular dark field scanning transmission electron microscopy. Atom counting method, with size selected Au clusters as mass standards, was employed to determine the number of iron atoms in the nanoparticle core of each ferritin protein. Quantitative analysis shows that the nuclearity of iron atoms in the mineral core varies from a few hundred iron atoms to around 5000 atoms. Moreover, a relationship between the iron loading and iron core morphology is established, in which mineral core nucleates from a single nanoparticle, then grows along the protein shell before finally forming either a solid or hollow core structure.
作为主要的铁储存蛋白，铁蛋白为维持动物、植物和细菌体内铁的平衡而储存和释放铁。我们利用像差校正的高角环形暗场扫描透射电子显微镜研究了铁蛋白（来自马脾）的形态和铁负载情况。原子计数法使用经过尺寸筛选的 Au 团簇作为质量标准，来确定每个铁蛋白中纳米颗粒核心的铁原子数量。定量分析表明，矿物质核心中铁原子的核性从几百个铁原子到大约 5000 个原子不等。此外，还建立了铁负载与铁核心形态之间的关系，其中矿物质核心从单个纳米颗粒开始形成，然后沿着蛋白质外壳生长，最终形成实心或空心核心结构。
