Self-Organization of Biomolecular Functional Nanostructures

Itamar Willner

Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 91904, Israel




The base sequence of nucleic acids encodes structural and reactivity functions into the DNA. The reactivity of the information encoded in nucleic acids will be demonstrated with the design of DNA machines for the amplified detection of DNA,[1] low molecular weight substances (cocaine)[2] and Hg2+ ions. DNA machines are also used to generate scaffolds of aptamer units for the ordering of proteins in the form of organized wires. The organization of proteins on DNA scaffolds (templates) is an important motif to yield functional catalytic nanostructures. This will be exemplified with the self-assembly of catenated DNA chains and their use as scaffolds to assemble different proteins. Similarly, hexagon DNA wires of controlled width are designed, and these act as templates for the ordered assembly of enzymes and the activation of an enzymatic cascade.

A further topic that will be addressed is the use of nanoparticle (NP)-enzyme conjugates as functional units for the evolution of metallic nanowires and biomolecules of improved bioelectronic functions. The electrical contacting of redox enzymes with electrodes was accomplished by the reconstitution of apo-enzymes on cofactor-functionalized Au NPs.[3] A new approach to effectively electrically contact redox enzymes with electrodes involves the biocatalytic evolution of Au NPs on the enzyme, and the immobilization of relay units on the NPs. Also, the Au NP-functionalized enzyme units act as biocatalysts for the formation of metallic nanowires.[4]