Diatom Nanobiotechnology:Design Principles for Enhancing the Catalytic Activities of Enzymes and Metal Nanoparticles immobilized on Diatom Biosilica

硅藻是单细胞微生物，具有显著的二氧化硅(SiO_2)形成能力。硅藻二氧化硅显示出纳米到微米级的分级模式，这赋予了材料有趣的特性，这些特性很难合成复制。该项目将在温和的反应条件下沉积无机材料的方法与硅藻二氧化硅生物生成的遗传操作相结合，以合成具有有趣的光学、催化和磁性的层次化结构的有机-无机杂化材料。这种方法是基于产生转基因硅藻菌株，在二氧化硅支架的选定区域暴露定制的功能蛋白。在矿物形成蛋白的情况下，这将允许无机纳米颗粒沉积在二氧化硅支架的明确定义的区域。受体/配体蛋白质的掺入旨在使从趋磁性细菌中分离出来的适当修饰的磁性纳米颗粒能够定点附着。通过磁性和受体/配体修饰的硅藻二氧化硅的自组装，我们的目标是首次产生这种独特的生物材料的有序2D和3D超结构。

Diatoms are single-celled microorganisms with remarkable SiO2 (silica) forming capabilities. Diatom silica exhibits hierarchical patterns of nano- to mircoscale features, which endow the material with interesting properties that are difficult to reproduce synthetically. The project combines methods for the deposition of inorganic materials under mild reaction conditions with genetic manipulation of diatom silica biogenesis to synthesize hierarchically structured organic-inorganic hybrid materials with interesting optical, catalytic, and magnetic properties. This approach is based on generating transgenic diatom strains that expose tailored functional proteins in selected region of the silica scaffold. In case of mineral forming proteins this is expected to allow for the deposition of inorganic nanoparticles in well defined regions of the silica scaffold. The incorporation of receptor/ligand proteins is aimed at enabling the site-specific attachment of appropriately modified magnetic nanoparticles that have been isolated from magnetotactic bacteria. Through self-assembly of magnetic and receptor/ligand modified diatom silica we aim to generate for the first time ordered 2D and 3D superstructures of this unique biological material.