On the existence of superradiant excitonic states in microtubules

Model supporting possible transmission of UV in microtubules with great efficiency and coherent energy transfer.

" Our analysis has shown that the coupling between tryotophan molecules is able to create a superradiant ground state, similar to the physical behavior of several photosynthetic antenna systems. Such a superradiant ground state, which absorbs in the UV spectral range, has been shown to be a coherent excitonic state extended over the whole microtubule lattice of tryptophan molecules. Interestingly, the superradiant ground state appears to be delocalized on the exterior wall of the microtubule, which interfaces with the cytoplasm, suggesting the possibility that these extended but shortlived (few picosecond) excitonic states may be involved in communication with cellular proteins that bind to microtubules in order to carry out their functions. At the same time, we have shown that long-lived (hundreds of milliseconds) subradiant states can be concentrated on the inner wall of the microtubule lumen, potentially maintaining excitonic transfer processes across the cytoskeletal network in a more “protected” thermodynamic milieu. These subradiant states could be particularly important in the synchronization of neuronal processes in the brain, where microtubules can extend to the micron scale and beyond." {Credits 1}

{Credits 1} 🎪 G L Celardo et al 2019 New J. Phys. 21 023005, DOI: https://doi.org/10.1088/1367-2630/aaf839. © 2019 The Author(s). Original content from this work may be used under the terms of the Creative Commons Attribution 3.0 licence.