Specific and Non-specific Interaction of M13 Bacteriophage Proteins with Inorganic Nanomaterials

Open Access
Author:
Essinger-hileman, Elizabeth Ruth
Graduate Program:
Chemistry
Degree:
Doctor of Philosophy
Document Type:
Dissertation
Date of Defense:
May 10, 2013
Committee Members:
  • Raymond Edward Schaak, Dissertation Advisor
  • Christine Dolan Keating, Committee Member
  • John H Golbeck, Committee Member
  • Robert Martin Rioux Jr., Committee Member
Keywords:
  • inorganic nanomaterials
  • M13 bacteriophage
  • specific peptides
  • material specificity
  • nanoparticles
Abstract:
The application of lessons learned from biological systems to chemistry and materials science has allowed researchers to impact technologies such as solar energy, antibacterial and stain resistant clothing, and energy storage. These biomimetic studies and techniques hold promise to address challenges present in nanomaterial synthesis and application. One biomimetic system that has been used to address these challenges is peptide phage display, in which the M13 bacteriophage virus is used to identify peptides that are specific for target materials. These peptides are then used either attached to the virus or separate from the virus for a variety of applications ranging from nanoparticle synthesis to batteries to solar energy harvest. This dissertation describes the study and use of specific and nonspecific interactions of M13 bacteriophage proteins with inorganic nanomaterials. We first use the biological environment inherent for the incorporation of M13 bacteriophage – aqueous solution, room temperature, and atmospheric pressure – to synthesize metastable alloy nanoparticles of Au-Rh, Au-Pt, Pt-Rh, and Pd-Rh. By changing the ratio of the precursor metal salt solutions, the composition of the alloy nanoparticles can be tuned across the entire bulk miscibility gap. A variety of molecular and polymeric stabilizers can be used in this synthesis, and the alloy nanoparticles can be synthesized in the presence of a porous support or M13 bacteriophage. The next demonstration of the usefulness of M13 bacteriophage is the use of a gold-specific peptide identified via peptide phage display as part of a system to magnetically separate non-magnetic materials. The gold-specific peptide is covalently linked to Strep Tag II, a biotin analogue that will bind strongly to streptavidin. This peptide is used to link gold nanoparticles to streptavidin-coated iron oxide particles, which can then be separated from solution using a benchtop permanent magnet. Gold nanoparticles are sequestered from solution as well as separated from a mixture of gold and cadmium sulfide or cadmium selenide nanoparticles. Finally, we demonstrate the ability to use isothermal titration calorimetry to semi-quantitatively study the binding of a phage display identified platinum-specific peptide to an as-synthesized platinum nanoparticles solution. The peptide is twelve amino acids long with five constituent amino acid residues – glycine, leucine, proline, lysine, and histidine. By studying the binding of these amino acids as well as small portions of the full peptide to the platinum nanoparticle solution, we find that histidine and histidine-containing peptides bind to the nanoparticle solution with exothermic heats of binding. We also study the origin of this binding and find that the major contribution is from binding of histidine to the platinum precursor still present in the nanoparticle solution. Binding of histidine to a purified nanoparticle sample is endothermic in nature with a different characteristic binding curve than for the as-synthesized nanoparticle solution.