Accession Number:

ADA488475

Title:

Stokes Efficiency of Molecular Motor-Cargo Systems

Descriptive Note:

Journal article

Corporate Author:

CALIFORNIA UNIV SANTA CRUZ DEPT OF APPLIED MATHEMATICS AND STATISTICS

Personal Author(s):

Report Date:

2008-01-01

Pagination or Media Count:

15.0

Abstract:

A molecular motor utilizes chemical free energy to generate a unidirectional motion through the viscous fluid. In many experimental settings and biological settings, a molecular motor is elastically linked to a cargo. The stochastic motion of a molecular motor-cargo system is governed by a set of Langevin equations, each corresponding to an individual chemical occupancy state. The change of chemical occupancy state is modeled by a continuous time discrete space Markov process. The probability density of a motor-cargo system is governed by a two-dimensional Fokker-Planck equation. The operation of a molecular motor is dominated by high viscous friction and large thermal fluctuations from surrounding fluid. The instantaneous velocity of a molecular motor is highly stochastic the past velocity is quickly damped by the viscous friction and the new velocity is quickly excited by bombardments of surrounding fluid molecules. Thus, the theory for macroscopic motors should not be applied directly to molecular motors without close examination. In particular, a molecular motor behaves differently working against a viscous drag than working against a conservative force.

Subject Categories:

  • Statistics and Probability
  • Fluid Mechanics
  • Atomic and Molecular Physics and Spectroscopy

Distribution Statement:

APPROVED FOR PUBLIC RELEASE