Biometra Department, University of Milan, Milan, Italy.
Department of Biosciences, University of Milan, Milan, Italy.
Int J Biol Macromol. 2024 Sep;276(Pt 2):133812. doi: 10.1016/j.ijbiomac.2024.133812. Epub 2024 Jul 19.
The characterization of the structure of ferritin in solution and the arrangement of iron stored in its cavity are intriguing subjects for both cell biology and applied science, since the protein structure, stability, and easiness of production make it an ideal tool for biomedical applications. We characterized the ferritin structure over a wide range of iron loadings by visible light, X-ray, and neutron scattering techniques. We found that the arrangement of iron ions inside the protein cage resulted in a more disposable arrangement at lower loading factors and then in a crystalline structure. At very high iron content the inner core is composed of magnetite more than ferrihydrite, and the shell of the protein is elastically deformed by the iron crystal growth in an ellipsoidal arrangement. The application of an external radiofrequency (RF) magnetic field affected ferritins at low iron loading factors. Notably the RF modified the iron disposition towards a more dispersed arrangement. The structural characterization of the ferritin at different LFs and in presence of magnetic fields provides useful insights into their physiological behaviour and can help in the design and fine-tuning of ferritin-based nanosystems for biotechnological applications.
铁蛋白在溶液中的结构特征及其腔内储存的铁的排列是细胞生物学和应用科学都非常感兴趣的课题，因为该蛋白质的结构、稳定性和易于生产使其成为生物医学应用的理想工具。我们使用可见光、X 射线和中子散射技术在广泛的铁负载范围内对铁蛋白结构进行了表征。我们发现，铁离子在蛋白质笼内的排列导致在较低的负载因子下形成更具可分配性的排列，然后形成结晶结构。在铁含量非常高的情况下，内核由磁铁矿组成，而不是水铁矿，并且蛋白质外壳由于铁晶体在椭圆排列中的生长而发生弹性变形。外加射频（RF）磁场会影响铁蛋白在低铁负载因子下的状态。值得注意的是，RF 会将铁的排列方式修改为更分散的排列。在不同 LF 和磁场存在下对铁蛋白的结构表征为它们的生理行为提供了有用的见解，并有助于基于铁蛋白的纳米系统的设计和微调，以用于生物技术应用。
