Nanoscale objects feature very large surface-area-to-volume ratios and are now understood as powerful tools for catalysis, but their nature as nanomaterials brings challenges including toxicity and nanomaterial pollution. Immobilization is considered a feasible strategy for addressing these limitations. Here, as a proof-of-concept for the immobilization of nanoscale catalysts in the extracellular matrix of bacterial biofilms, we genetically engineered amyloid monomers of the Escherichia coli curli nanofiber system that are secreted and can self-assemble and anchor nano-objects in a spatially precise manner. We demonstrated three scalable, tunable and reusable catalysis systems: biofilm-anchored gold nanoparticles to reduce nitro aromatic compounds such as the pollutant p-nitrophenol, biofilm-anchored hybrid Cd_0.9Zn_0.1S quantum dots and gold nanoparticles to degrade organic dyes and biofilm-anchored CdSeS@ZnS quantum dots in a semi-artificial photosynthesis system for hydrogen production. Our work demonstrates how the ability of biofilms to grow in scalable and complex spatial arrangements can be exploited for catalytic applications and clearly illustrates the design utility of segregating high-energy nano-objects from injury-prone cellular components by engineering anchoring points in an extracellular matrix.

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用于催化应用的活体工程细菌生物膜中功能性纳米物体的固定

纳米级物体具有非常大的表面积与体积比，现在被认为是强大的催化工具，但它们作为纳米材料的性质带来了包括毒性和纳米材料污染在内的挑战。固定被认为是解决这些限制的可行策略。在这里，作为将纳米级催化剂固定在细菌生物膜的细胞外基质中的概念验证，我们对大肠杆菌卷曲纳米纤维系统的淀粉样单体进行了基因工程改造，这些单体被分泌并且可以自组装和锚定纳米物体。空间精确的方式。我们展示了三种可扩展、可调和可重复使用的催化系统：生物膜锚定的金纳米粒子，以减少硝基芳香化合物，如污染物p-硝基苯酚、生物膜锚定的混合 Cd _0.9 Zn _0.1 S 量子点和金纳米粒子，用于在半人工光合作用系统中降解有机染料和生物膜锚定的 CdSeS@ZnS 量子点，用于制氢。我们的工作展示了如何利用生物膜在可扩展和复杂的空间排列中生长的能力用于催化应用，并清楚地说明了通过设计细胞外基质中的锚定点将高能纳米物体与易受伤的细胞成分分离的设计效用.