Genetic Logic Gates Enable Patterning of Amyloid Nanofibers

• Published in: Advanced materials (Weinheim) 2019-09, Vol.31 (39), p.e1902888-n/a
• Main Authors: Kalyoncu, Ebuzer, Ahan, Recep Erdem, Ozcelik, Cemile Elif, Seker, Urartu Ozgur Safak
• Format: Article
• Language: English
• Subjects: Amyloid - chemistry; amyloid fibers; biofilm patterning; Biomedical materials; Boolean algebra; Cellular structure; Composition; Computers, Molecular; Escherichia coli - genetics; Escherichia coli Proteins - genetics; genetic circuits; Genetic Engineering; genetic logic gates; Gold; Logic; Logic circuits; Materials science; Microorganisms; Nanofibers; Nanofibers - chemistry; Nanoparticles; Nanotechnology - methods; Nickel; Nitrilotriacetic acid; recombinase; Recombinases - genetics
• ISSN: 0935-9648; 1521-4095
• DOI: 10.1002/adma.201902888

Distinct spatial patterning of naturally produced materials is observed in many cellular structures and even among communities of microorganisms. Reoccurrence of spatially organized materials in all branches of life is clear proof that organization is beneficial for survival. Indeed, organisms can trick the evolutionary process by using organized materials in ways that can help the organism to avoid unexpected conditions. To expand the toolbox for synthesizing patterned living materials, Boolean type “AND” and “OR” control of curli fibers expression is demonstrated using recombinases. Logic gates are designed to activate the production of curli fibers. The gates can be used to record the presence of input molecules and give output as CsgA expression. Two different curli fibers (CsgA and CsgA‐His‐tag) production are then selectively activated to explore distribution of monomers upon coexpression. To keep track of the composition of fibers, CsgA‐His‐tag proteins are labeled with nickel–nitrilotriacetic acid (Ni–NTA‐) conjugated gold nanoparticles. It is observed that an organized living material can be obtained upon inducing the coexpression of different CsgA fibers. It is foreseen that living materials with user‐defined curli composition hold great potential for the development of living materials for many biomedical applications. Synthetic‐biology‐enabled devices can be used for biomaterial assembly and patterning. Biological polymers including biofilm fibers and spider silk are formed by specific proteins that are synthetized in monomeric form and assembled into higher ordered structures. Recombinase‐integrated genetic logic gates are employed to control patterning of bacterial biofilm nanofibers for the assembly of gold nanoparticles.