Genetically Engineered Organization: Protein Template, Biological Recognition Sites, and Nanoparticles. Issue 1 (28th June 2016) - Jehle, Franziska
Abstract : Nanoparticles and their assemblies exhibit properties that can be used for a wide range of applications. However, creating multifunctional assemblies has remained challenging. Inspired by magnetotactic bacteria, genetically engineered single building blocks from magnetosome chains are used and complemented by additional components to form fluorescent assemblies of nanoparticles of varying types. This strategy is illustrated by the use of a protein from magnetotactic bacteria (MamK) known to form filaments in vivo and in vitro. A fusion protein of MamK and the fluorescent protein mCherry is recombinantly expressed and isolated using a hexahistidine tag that is subsequently used to bind functionalized gold nanoparticles to polymerized MamK_mCherry_His6 filaments. The versatility of this modular approach is further exemplified by the concomitant addition of biological or synthetic magnetic nanoparticles functionalized with a nanobody directed against mCherry. The as‐formed structures are fluorescent and can be actuated by an external magnetic field. This study shows again how nature's strategies can be applied for designing multifunctional materials. Abstract : Proteins from microorganisms can be used as a versatile basis to form 1D multifunctional materials. A genetically engineered version of mamK, the gene responsible for magnetosome organization in magnetotactic bacteria, is used to create a fluorescent scaffold to which different nanoparticles can be attached. The materials can be actuated by magnetic fields when magnetic nanoparticles are used.