Comment on "Relative Diffusivities of Bound and Unbound Protein Can Control Chemotactic Directionality''

Jaime Agudo-Canalejo; Pierre Illien; Ramin Golestanian

doi:10.1021/acs.langmuir.1c02840

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arXiv · 2110.12797

Comment on "Relative Diffusivities of Bound and Unbound Protein Can Control Chemotactic Directionality''

Jaime Agudo-Canalejo·Pierre Illien·Ramin Golestanian

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Abstract

This is a comment on a recently published paper in Langmuir: Mandal, N. S.; Sen, A. Relative Diffusivities of Bound and Unbound Protein Can Control Chemotactic Directionality. Langmuir 2021, PMID: 34647749 [arXiv:2103.13469]. In this study, Mandal and Sen claim to propose a new kinetic model to analyze the directional movement of enzyme molecules in response to a gradient of their substrate, 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, and movement down the substrate gradient when the diffusivity of the substrate-bound enzyme is higher than that of the unbound enzyme. They develop this theoretical scheme to present an alternative to our previously published theoretical framework [Agudo-Canalejo, J.; Illien, P.; Golestanian, R. Phoresis and enhanced diffusion compete in enzyme chemotaxis. Nano Lett. 2018, 18, 2711-2717; arXiv:2104.02394]. We demonstrate that despite their claim, what they present is exactly the same theory as our work, and therefore, we conclude that their claim of novelty is unsubstantiated.

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Jaime Agudo-Canalejo, Pierre Illien, Ramin Golestanian. 2021-10-25. Comment on "Relative Diffusivities of Bound and Unbound Protein Can Control Chemotactic Directionality''. https://doi.org/10.1021/acs.langmuir.1c02840

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