title: Atomic water channel controlling remarkable properties of a single brain microtubule: correlating single protein to its supramolecular assembly.
abstract: Microtubule nanotubes are found in every living eukaryotic cells; these are formed by reversible polymerization of the tubulin protein, and their hollow fibers are filled with uniquely arranged water molecules. Here we measure single tubulin molecule and single brain-neuron extracted microtubule nanowire with and without water channel inside to unravel their unique electronic and optical properties for the first time. We demonstrate that the energy levels of a single tubulin protein and single microtubule made of 40,000 tubulin dimers are identical unlike conventional materials. Moreover, the transmitted ac power and the transient fluorescence decay (single photon count) are independent of the microtubule length. Even more remarkable is the fact that the microtubule nanowire is more conducting than a single protein molecule that constitutes the nanowire. Microtubule's vibrational peaks condense to a single mode that controls the emergence of size independent electronic/optical properties, and automated noise alleviation, which disappear when the atomic water core is released from the inner cylinder. We have carried out several tricky state-of-the-art experiments and identified the electromagnetic resonance peaks of single microtubule reliably. The resonant vibrations established that the condensation of energy levels and periodic oscillation of unique energy fringes on the microtubule surface, emerge as the atomic water core resonantly integrates all proteins around it such that the nanotube irrespective of its size functions like a single protein molecule. Thus, a monomolecular water channel residing inside the protein-cylinder displays an unprecedented control in governing the tantalizing electronic and optical properties of microtubule.
authors.affiliation: Nano Characterization Unit, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan.
authors.forename: Satyajit
authors.initials: S
authors.lastname: Sahu
authors.forename: Subrata
authors.initials: S
authors.lastname: Ghosh
authors.forename: Batu
authors.initials: B
authors.lastname: Ghosh
authors.forename: Krishna
authors.initials: K
authors.lastname: Aswani
authors.forename: Kazuto
authors.initials: K
authors.lastname: Hirata
authors.forename: Daisuke
authors.initials: D
authors.lastname: Fujita
authors.forename: Anirban
authors.initials: A
authors.lastname: Bandyopadhyay
mesh_terms: D001921:Brain / Q000648:ultrastructure*; D007700:Kinetics; D008870:Microtubules / Q000737:chemistry*; D043942:Nanotubes / Q000737:chemistry; D055503:Protein Multimerization; D014404:Tubulin / Q000737:chemistry* / Q000648:ultrastructure; D014867:Water / Q000737:chemistry
chemical_list: D014404:Tubulin; D014867:Water