Jump to main content
Jump to site search
PLANNED MAINTENANCE Close the message box

Scheduled maintenance upgrade on Thursday 4th of May 2017 from 8.00am to 9.00am (BST).

During this time our websites will be offline temporarily. If you have any questions please use the feedback button on this page. We apologise for any inconvenience this might cause and thank you for your patience.


Volume 195, 2016
Previous Article Next Article

Optical vs. chemical driving for molecular machines

Author affiliations

Abstract

Molecular machines use external energy to drive transport, to do mechanical, osmotic, or electrical work on the environment, and to form structure. In this paper the fundamental difference between the design principles necessary for a molecular machine to use light or external modulation of thermodynamic parameters as an energy source vs. the design principle for using an exergonic chemical reaction as a fuel will be explored. The key difference is that for catalytically-driven motors microscopic reversibility must hold arbitrarily far from equilibrium. Applying the constraints of microscopic reversibility assures that a coarse grained model is consistent with an underlying model for motion on a single time-independent potential energy surface. In contrast, light-driven processes, and processes driven by external modulation of the thermodynamic parameters of a system cannot in general be described in terms of motion on a single time-independent potential energy surface, and the rate constants are not constrained by microscopic reversibility. The results presented here call into question the value of the so-called power stroke model as an explanation of the function of autonomous chemically-driven molecular machines such as are commonly found in biology.

Back to tab navigation
Please wait while Download options loads

Publication details

The article was received on 30 May 2016, accepted on 15 Jun 2016 and first published on 15 Jun 2016


Article type: Paper
DOI: 10.1039/C6FD00140H
Citation: Faraday Discuss., 2016,195, 583-597
  •   Request permissions

    Optical vs. chemical driving for molecular machines

    R. D. Astumian, Faraday Discuss., 2016, 195, 583
    DOI: 10.1039/C6FD00140H

Search articles by author