a Department of Biology, Faculty of Basic Science, Research and Science Branch , Islamic Azad University of Tehran , Tehran , Iran.
b Department of Nanotechnology, Faculty of Advance Science and Technology, Pharmaceutical Sciences Branches , Islamic Azad University of Tehran (IAUPS) , Tehran , Iran.
J Biomol Struct Dyn. 2018 Aug;36(11):2908-2916. doi: 10.1080/07391102.2017.1371645. Epub 2017 Sep 18.
The nanoparticle (NP)-induced conformational changes of protein and NP agglomeration have gained a remarkable interest in medical and biotechnological fields. Herein, the effect of human hemoglobin (Hb) on the colloidal stability of cerium oxide NP (CNP) was investigated by dynamic light scattering (DLS), zeta potential, and TEM analysis. In addition, the effect of CNP on the heme degradation and structural changes of Hb was studied using fluorescence, circular dichroism (CD), and UV-visible (UV-vis) spectroscopic methods. DLS and TEM analysis showed that the presence of Hb can increase the mean diameter of CNP. Zeta potential measurements revealed that CNP demonstrated a higher charge distribution relative to CNP/Hb complex. Besides, fluorescence studies indicated that two fluorescent heme degradation products are revealed during the interaction of CNP with Hb. Near UV-CD spectroscopy also showed that the microenvironmental changes of heme groups occur after interaction of Hb with CNP. The result of thermal behavior of Hb confirmed the structural changes of protein, which referred to decrease in the Hb stability in the presence of CNP. Indeed, the finding related to structural and functional changes of Hb induced by CNP may be crucial to obtain information regarding the side effects of NPs. Finally, this data reveal much insight into the effects of the interaction on protein structural changes and NP agglomeration, and can correlate the zeta potential of NP-protein complexes with the nature of the principle NP-protein interaction.
纳米粒子（NP）诱导的蛋白质构象变化和 NP 聚集在医学和生物技术领域引起了极大的关注。在此，通过动态光散射（DLS）、动电电位和 TEM 分析研究了人血红蛋白（Hb）对氧化铈 NP（CNP）胶体稳定性的影响。此外，还使用荧光、圆二色性（CD）和紫外可见（UV-vis）光谱法研究了 CNP 对血红素降解和 Hb 结构变化的影响。DLS 和 TEM 分析表明，Hb 的存在会增加 CNP 的平均粒径。动电电位测量表明，与 CNP/Hb 复合物相比，CNP 表现出更高的电荷分布。此外，荧光研究表明，在 CNP 与 Hb 相互作用期间，会出现两种荧光血红素降解产物。近紫外 CD 光谱也表明，在 CNP 与 Hb 相互作用后，血红素基团的微环境发生变化。Hb 的热行为结果证实了蛋白质的结构变化，这表明在 CNP 存在的情况下，Hb 的稳定性降低。事实上，与 CNP 诱导的 Hb 结构和功能变化相关的发现对于获得有关 NPs 副作用的信息可能至关重要。最后，这些数据深入了解了相互作用对蛋白质结构变化和 NP 聚集的影响，并可以将 NP-蛋白质复合物的动电电位与 NP-蛋白质相互作用的本质联系起来。
