Computational modelling of the stochastic dynamics of kinesin biomolecular motors

The intracellular motion of the kinesin motor proteins, based on an asymmetric hand-over-hand mechanism, within a stochastically fluctuating medium is simulated via the Langevin dynamics in which the random intracellular fluctuations are represented by a white noise. The kinesin heads are subject to both a flashing ratchet potential, that represents their interaction with the microtubule track and models the random hydrolysis of the adenosine triphosphate (ATP) molecule that drives the motion forward, and a bistable potential that correlates their motion. Our computed results are in good agreement with the experimental data related to the hydrolysis of one ATP molecule per one step of motion, the space-time trajectories of the heads, the variation of the kinesin velocity with the applied external force, and the processivity nature of the kinesin motion. (c) 2007 Elsevier B.V. All rights reserved.