title: Synthetic Biogenesis of Bacterial Amyloid Nanomaterials with Tunable Inorganic-Organic Interfaces and Electrical Conductivity.
abstract: Amyloids are highly ordered, hierarchal protein nanoassemblies. Functional amyloids in bacterial biofilms, such as Escherichia coli curli fibers, are formed by the polymerization of monomeric proteins secreted into the extracellular space. Curli is synthesized by living cells, is primarily composed of the major curlin subunit CsgA, and forms biological nanofibers with high aspect ratios. Here, we explore the application of curli fibers for nanotechnology by engineering curli to mediate tunable biological interfaces with inorganic materials and to controllably form gold nanoparticles and gold nanowires. Specifically, we used cell-synthesized curli fibers as templates for nucleating and growing gold nanoparticles and showed that nanoparticle size could be modulated as a function of curli fiber gold-binding affinity. Furthermore, we demonstrated that gold nanoparticles can be preseeded onto curli fibers and followed by gold enhancement to form nanowires. Using these two approaches, we created artificial cellular systems that integrate inorganic-organic materials to achieve tunable electrical conductivity. We envision that cell-synthesized amyloid nanofibers will be useful for interfacing abiotic and biotic systems to create living functional materials..
authors: Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States.|Department of Biological Engineering, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States.|UNAM-Institute of Materials Science and Nanotechnology, Bilkent University , 06800 Ankara, Turkey.
authors: Urartu Ozgur Safak
authors: UO
authors: Seker
authors: Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States.|Department of Biological Engineering, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States.
authors: Allen Y
authors: AY
authors: Chen
authors: Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States.|Department of Biological Engineering, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States.|MIT Microbiology Program , 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
authors: Robert J
authors: RJ
authors: Citorik
authors: Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States.|Department of Biological Engineering, Massachusetts Institute of Technology , Cambridge, Massachusetts 02139, United States.|MIT Microbiology Program , 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States.
authors: Timothy K
authors: TK
authors: Lu
mesh_terms: D000682:Amyloid / Q000378:metabolism*; D001426:Bacterial Proteins / Q000378:metabolism; D018441:Biofilms / Q000254:growth & development; D004553:Electric Conductivity; D004926:Escherichia coli / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000378:metabolism; D006046:Gold / Q000378:metabolism; D053768:Metal Nanoparticles / Q000382:microbiology; D057139:Nanofibers; D049329:Nanostructures / Q000382:microbiology*; D036103:Nanotechnology / Q000379:methods; D053770:Nanowires / Q000382:microbiology; D010316:Particle Size
chemical_list: D000682:Amyloid; D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; C077481:Crl protein, Bacteria; D006046:Gold
keywords: biofilm proteins; functional amyloids; living materials; nanomaterial assembly