Nucleation of Iron Oxide Nanoparticles Mediated by Mms6 Protein in Situ
Nucleation of Iron Oxide Nanoparticles Mediated by Mms6 Protein in Situ
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DOI：
10.1021/nn502551y
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发表时间：
2014-09-01
期刊：
影响因子：
17.1
通讯作者：
Prozorov, Tanya
中科院分区：
文献类型：
--
作者：
Kashyap, Sanjay;Woehl, Taylor J.;Prozorov, Tanya
生物矿化蛋白作为模板剂广泛应用于多种有机-无机纳米结构的仿生合成。然而，蛋白质在控制仿生颗粒成核和生长中的作用尚不清楚，因为生物激发反应的机制通常是通过对所得纳米级矿物相的原位分析来推断的。在这里，我们报告了在氯化铁培养的Mms6蛋白胶束中加入氢氧化钠诱导的原位反应中，由酸性细菌重组蛋白Mms6介导的仿生氧化铁纳米颗粒成核的直接可视化。利用原位液细胞扫描透射电子显微镜观察到铁液预成核阶段和新生的非晶纳米颗粒优先在蛋白质胶束表面形成。我们的研究结果为蛋白质介导的氧化铁仿生成核的早期步骤提供了见解，并指出了在纳米颗粒形成过程中扩展蛋白质表面的重要性。
Biomineralization proteins are widely used as templating agents in biomimetic synthesis of a variety of organic-inorganic nanostructures. However, the role of the protein in controlling the nucleation and growth of biomimetic particles is not well understood, because the mechanism of the bioinspired reaction is often deduced from at situ analysis of the resultant nanoscale mineral phase. Here we report the direct visualization of biomimetic iron oxide nanoparticle nucleation mediated by an acidic bacterial recombinant protein, Mms6, during an in situ reaction induced by the controlled addition of sodium hydroxide to solution-phase Mms6 protein micelles incubated with ferric chloride. Using in situ liquid cell scanning transmission electron microscopy we observe the liquid iron prenucleation phase and nascent amorphous nanoparticles forming preferentially on the surface of protein micelles. Our results provide insight into the early steps of protein-mediated biomimetic nucleation of iron oxide and point to the importance of an extended protein surface during nanoparticle formation.