Abstract: Conventional top-down lithographic processes approach their practical and theoretical limits at dimensional scales less than 100 nm. Alternative bottom-up methods are being investigated for building nanoscale architectures including the use of bio-supramolecular structures as templates. In this study, fabrication of microtubule-based nanowires is investigated and electrical properties of these nanowires are reported. Microtubules (MTs) are fibrous proteins found in nearly all eukaryotes. They typically form long hollow tubes about 25 nm in outer diameter and microns in length. The protein filament is composed of αβ-tubulin dimers and can be assembled in vitro. MT-templated Ni nanowires were fabricated by reducing Ni2+ to Ni0 on Pd activated MT surface. Electrical measurements of the Ni nanowire showed resistor-like behavior. Au nanowires were also formed on Si substrates using a seed and growth approach. MTs were first adsorbed onto silicon substrates and then covalently linked to 1.4 nm Au particles functionalized with sulfo-N-hydroxy-succinimide. A subsequent photochemical process reduced Au3+ and enlarged the Au particles, improving Au coverage on the MT. Surface Enhanced Raman Spectroscopy and X-ray Photoelectron Spectroscopy were used to probe the Au binding sites on the protein filament. Focused ion beam was used to deposit electrodes on the MT-templated Au nanowires and the electrical conductivities of these Au nanowires were determined. Current-voltage (I-V) measurements showed a linear I-V characteristic at voltages as high as 15V and the calculated resistivity of a 23 μm MT Au nanowire was 7.3 x 10-5 Ω-m. Conductive AFM measurements made on the Au nanowires showed interesting memory-like bistable behavior. A single MT-templated Au nanowire switched from an initial low conductivity state (OFF state) to a high conductivity state (ON state) when an applied voltage surpasses 4.5V. By applying a reverse voltage bias, the MT-Au nanowires returned to their original OFF state. This switching behavior between the OFF and ON state is comparable to the writing process in a digital memory element. Finally, self-assembly of parallel arrays of MTs was achieved by adding tau proteins to the tubulins during the polymerization reaction. The arrays were then metallized with Au, demonstrating the feasibility of fabricating MT-Au nanowire arrays using biotemplates and self-assembly methods.