Ozaki Makoto, Imai Takahito, Tsuruoka Takaaki, Sakashita Shungo, Tomizaki Kin-Ya, Usui Kenji
Faculty of Frontiers of Innovative Research in Science and Technology (FIRST), Konan University, 7-1-20 Minatojima-minamimachi, Chuo-ku, Kobe, 650-0047, Japan.
Department of Materials Chemistry, Ryukoku University, 1-5 Yokotani, Seta Oe-cho, 520-2194, Otsu, Japan.
Commun Chem. 2021 Jan 4;4(1):1. doi: 10.1038/s42004-020-00440-8.
Biomineralization, the precipitation of various inorganic compounds in biological systems, can be regulated in terms of the size, morphology, and crystal structure of these compounds by biomolecules such as proteins and peptides. However, it is difficult to construct complex inorganic nanostructures because they precipitate randomly in solution. Here, we report that the elemental composition of inorganic nanocomposites can be controlled by site-specific mineralization by changing the number of two inorganic-precipitating peptides bound to DNA. With a focus on gold and titania, we constructed a gold-titania photocatalyst that responds to visible light excitation. Both microscale and macroscale observations revealed that the elemental composition of this gold-titania nanocomposite can be controlled in several ten nm by changing the DNA length and the number of peptide binding sites on the DNA. Furthermore, photocatalytic activity and cell death induction effect under visible light (>450 nm) irradiation of the manufactured gold-titania nanocomposite was higher than that of commercial gold-titania and titania. Thus, we have succeeded in forming titania precipitates on a DNA terminus and gold precipitates site-specifically on double-stranded DNA as intended. Such nanometer-scale control of biomineralization represent a powerful and efficient tool for use in nanotechnology, electronics, ecology, medical science, and biotechnology.
生物矿化，即生物系统中各种无机化合物的沉淀过程，可通过蛋白质和肽等生物分子，依据这些化合物的大小、形态和晶体结构进行调控。然而，构建复杂的无机纳米结构颇具难度，因为它们会在溶液中随机沉淀。在此，我们报告称，通过改变与DNA结合的两种无机沉淀肽的数量，利用位点特异性矿化可控制无机纳米复合材料的元素组成。以金和二氧化钛为重点，我们构建了一种对可见光激发有响应的金 - 二氧化钛光催化剂。微观和宏观观察均表明，通过改变DNA长度以及DNA上肽结合位点的数量，这种金 - 二氧化钛纳米复合材料的元素组成可在几十纳米范围内得到控制。此外，所制备的金 - 二氧化钛纳米复合材料在可见光（>450 nm）照射下的光催化活性和诱导细胞死亡的效果高于市售的金 - 二氧化钛和二氧化钛。因此，我们成功地按预期在DNA末端形成了二氧化钛沉淀，并在位点特异性地在双链DNA上形成了金沉淀。这种对生物矿化的纳米级控制代表了一种用于纳米技术、电子学、生态学、医学和生物技术的强大而高效的工具。
