%0 Journal Article %T Comment on "Relative Diffusivities of Bound and Unbound Protein Can Control Chemotactic Directionality" %+ PHysicochimie des Electrolytes et Nanosystèmes InterfaciauX (PHENIX) %A Agudo-Canalejo, Jaime %A Illien, Pierre %A Golestanian, Ramin %< avec comité de lecture %@ 0743-7463 %J Langmuir %I American Chemical Society %8 2022-02-17 %D 2022 %Z Physics [physics]Journal articles %X In a recent study 1 published in Langmuir, 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. With the present Comment, we would like to point out that the exact same result and prediction (with an identical derivation) was already obtained by us as one of the central results in Ref. 2, whose Abstract indeed reads that we found "a new type of [chemotactic] mechanism due to binding-induced changes in the diffusion coefficient of the enzyme" which "points toward %G English %2 https://hal.science/hal-03863092/document %2 https://hal.science/hal-03863092/file/2110.12797.pdf %L hal-03863092 %U https://hal.science/hal-03863092 %~ ESPCI %~ CNRS %~ PARISTECH %~ INC-CNRS %~ PHENIX %~ PSL %~ SORBONNE-UNIVERSITE %~ SORBONNE-UNIV %~ SU-SCIENCES %~ ESPCI-PSL %~ SU-TI %~ ALLIANCE-SU %~ TEST2-HALCNRS %~ CHIMIE-SU