Living cells are able to synthesize a wide range of biomolecules whose precisely controlled size, shape, charge, linkage, molecular weight, functional groups, and binding affinity enable self-assembly. These molecular building blocks, including amino acids, carbohydrates, lipids, and nucleic acids, form macromolecular structures, whose functional properties often cannot be matched by man-made materials. To harness the advantages of biomolecules in the design of new materials, controlled methods of fabrication are needed. This dissertation focuses on advancing the understanding of the fabrication process of two biomaterials, phospholipids and self-organizing peptides.Phospholipids, the most abundant components in cell membranes, spontaneously form lipid bilayers in aqueous solution. Synthetic lipid bilayers in the form of small unilamellar vesicles (SUV) and supported bilayer lipid membranes (sBLM) are widely used to study membrane-mediated processes and to mimic natural membranes in surface-based devices. The two preferred methods to fabricate SUVs are extrusion and sonication. This study tested the hypothesis that the SUV fabrication method influenced key bilayer properties. The results confirmed that the morphology, average size and distribution of SUVs varied with the fabrication method. However, the molecular-scale behavior of the bilayer, as studied by fluorescence lifetime, anisotropy measurements, and translational diffusion was independent of the fabrication method.Some peptides self assemble into biologically important macromolecular structures and thus represent excellent candidates for bottom-up fabrication of nanostructured biomimetic materials. This study tested the hypothesis that synthetic analogues of the conductive pili produced by the metal-reducing bacterium Geobacter sulfurreducens could be fabricated in-vitro. Type IV pili are homopolymers of a pilin subunit (PilA) or pilin that polymerizes via hydrophobic interactions to form pili. The resulting synthetic protein nanowires could be potentially used to develop novel nanotechnologies, including nanoelectronic devices. Using genetic engineering and protein expression tools, a method to mass-produce pilA peptides was developed. In-vitro assembly of recombinant pilin subunits resulted in the formation of filaments with properties similar to native G. sulfurreducens pili including a similar diameter, tendency to aggregate into tangled bundles, and electrical conductivity. This achievement offers a potential cost-effective method to mass-produce protein nanowires for commercial applications.Collectively, this research provided important insights into the use of self-assembling biomolecules for bottom-up fabrication of functional and nanostructured biomimetic interfaces. It indicated that the liposome preparation method only affects physical properties of the vesicles (average size and distribution) but not the dynamics of rotational and translational diffusion of the bilayers. It also enabled production of recombinant pilin subunits into synthetic nanowires having properties similar to the native pili of G. sulfurreducens.
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