Relative Diffusivities of Bound and Unbound Protein Can Control Chemotactic Directionality.

@article{Mandal2021RelativeDO,
  title={Relative Diffusivities of Bound and Unbound Protein Can Control Chemotactic Directionality.},
  author={Niladri Sekhar Mandal and Ayusman Sen},
  journal={Langmuir : the ACS journal of surfaces and colloids},
  year={2021}
}
  • N. MandalAyusman Sen
  • Published 24 March 2021
  • Biology
  • Langmuir : the ACS journal of surfaces and colloids
Enzyme-based systems have been shown to undergo chemotactic motion in response to their substrate gradient. This phenomenon has been exploited to direct the motion of enzymes and enzyme-attached particles to specific locations in space. Here, we propose a new kinetic model to analyze the directional movement of an ensemble of protein molecules in response to a gradient of the ligand. We also formulate a separate model to probe the motion of enzyme molecules in response to a gradient of the… 
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Relative Diffusivities of Bound and Unbound Protein Can Control Chemotactic Directionality

A “new” kinetic model to analyze the directional movement of enzyme molecules in response to a gradient of their substrate is proposed, with the supposedly new prediction that net movement occurs up the substrate gradient when the diffusivity of the substrate-bound enzyme is lower than that of the unbound enzyme.

Comment on “Relative Diffusivities of Bound and Unbound Protein Can Control Chemotactic Directionality”

It is pointed out that the same result and prediction were already obtained by us as one of the central results in ref 2, whose abstract indeed states that the authors found “a new type of [chemotactic] mechanism due to binding-induced changes in the diffusion coefficient of the enzyme”.

Kinetic asymmetry versus dissipation in the evolution of chemical systems as exemplified by single enzyme chemotaxis

The results show that while dissipation ineluctably accompanies non-equilibrium phenomena, including chemotaxis, systems do not evolve to maximize dissipation, but rather to attain greatest kinetic stability.

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