Immobilization of functional nano-objects in living engineered bacterial biofilms for catalytic applications

• 来源期刊: 国家科学评论（英文版）
• 关键词: nanoscale catalyst immobilization semi-artificial photosynthesis living catalysis bio-inorganic hybrid system hydrogen production
• 年，卷（期）: 2019,（5）
• 页码范围: 929-943
• 页数: 15页
• 语种: 英文
• DOI: 10.1093/nsr/nwz104

摘要

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 ofnanoscale 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 Cd0.9Zn0.1 S 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 dearly illustrates the design utility of segregating high-energy nano-objects from injury-prone cellular components by engineering anchoring points in an extracellular matrix.