Modelling the influence of thermal effects induced by radio frequency electric field on the dynamics of the ATPase nano-biomolecular motors

Abstract

We model the dynamics of the F0 component of the F0F1-ATPase mitochondrion-based nano-motor operating in a stochastically-fluctuating medium that represents the intracellular environment. The stochastic dynamics are modeled via Langevin equation of motion wherein fluctuations are treated as white noise. We have investigated the influence of an applied alternating electric field on the rotary motion of the F0 rotor in such an environment. The exposure to the field induces a temperature rise in the mitochondrion's membrane, within which the F0 is embedded. The external field also induces an electric potential that promotes a change in the mitochondrion's transmembrane potential (TMP). Both the induced temperature and the change in TMP contribute to a change in the dynamics of the F0. We have found that for external fields in the radio frequency (RF) range, normally present in the environment and encountered by biological systems, the contribution of the induced thermal effects, relative to that of the induced TMP, to the dynamics of the F0 is more significant. The changes in the dynamics of the F0 part affect the frequency of the rotary motion of the F0F1-ATPase protein motor which, in turn, affects the production rate of the ATP molecules. © 2011 Associazione Italiana di Fisica Medica.