Qualitative Behavior of the Low-Frequency Vibrational Dynamics of Microtubules and the Surrounding Water.
The dynamics of the low-frequency vibrational modes of microtubules play a key role in many theoretical models regarding their biological function. We analyze these dynamics through large scale, classical molecular dynamics simulations of a microtubule composed of 42 tubulin heterodimers to provide insights into the qualitative nature of the vibrational energy absorption and dissipation mechanisms. The computed microtubule absorption spectra and vibrational density of states in the terahertz regime are presented, along with an analysis of the vibrational dephasing rates of the tubulin monomer center of mass dynamics, which are shown to be overdamped. Additionally, the presence of the microtubule modifies the dynamical properties of the solvation shell structure within roughly 10 Å of the protein. These vibrational properties are similar to those seen in other globular proteins and indicate microtubules are unlikely candidates for any large scale collective vibrational processes in the terahertz regime such as Fröhlich condensates.
General Dynamics Information Technology , 4141 Petroleum Road, JBSA Fort Sam Houston, Texas 78234-2644, United States.
Jeremy M
0000-0002-0585-3083
JM
Moix
General Dynamics Information Technology , 4141 Petroleum Road, JBSA Fort Sam Houston, Texas 78234-2644, United States.
James E
JE
Parker
Air Force Research Laboratory , 711th Human Performance Wing, Airman Systems Directorate, Bioeffects Division, Radio Frequency Bioeffects Branch, JBSA Fort Sam Houston, Texas 78234-2644, United States.
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