The name is absent

At the ends of growing microtubules, protofilaments of different lengths are
straight and closely associated. In shortening microtubules, protofilaments
separate from one another and curl back, away from the microtubule axis,
forming characteristic blunt “blossoms” at the microtubule ends (Tran et al., 1997;
Muller-Reichert et al., 1998). This observation is the basis for comments about
the tubulin dimer adopting a "curved" or "kidney-bean shaped" conformation, held
under tension in the microtubule lattice (Tran et al., 1997; Downing & Nogales,
1998). Localization of the hydrolyzed nucleotide at the inter-dimer interface is
highly suggestive, but which and how residues shift to generate tension and
weaken lateral bonds is an important subject of active research (Davis et al.,
1994; Sage et al., 1995).

The tubulin conformational states are multiple, with different energy barrier height
between them. Therefore we could conclude from the presented mechanism of
microtubule assembly <-> disassembly that the computational states
(representing bits or qubits) which a stable non-centrosomal neuronal
microtubule could adopt must be well chosen, so that to have both stable
microtubule structure and biological importance of the output tubulin states. Thus
it is obvious that the suggested electron hopping and the considered
GTP-hydrolysis linked tubulin dimer transitions (Hameroff, 2003a; 2003b;
Tuszynski, 2003; Mershin, 2003) having energy barrier of 0.4 eV are used in
biologically improper way in the constructed models to represent bits (or qubits).

The importance of the water microenvironment

NMR evidence (Cope, 1975; Hazelwood et al., 1969; 1974) strongly indicates
that cell water possesses more structure than liquid water, and that much of the
Na⁺ and K⁺ in the cell is not free in aqueous solution, but is associated with
charged sites on macromolecules (Cope, 1975). Therefore, complexed Na⁺ and
K⁺ cations have been compared to valence electrons in solid conductors and free

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