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Displacement Statistics of Unhindered Single Molecules Show no Enhanced Diffusion in Enzymatic Reactions.

ABSTRACT: Recent studies have sparked debate over whether catalytic reactions enhance the diffusion coefficients D of enzymes. Through high statistics of the transient (600 μs) displacements of unhindered single molecules freely diffusing in common buffers, we here quantify D for four enzymes under catalytic turnovers. We thus formulate how ∼ ±1% precisions may be achieved for D, and show no changes in diffusivity for catalase, urease, aldolase, and alkaline phosphatase under the application of wide concentration ranges of substrates. Our single-molecule approach thus overcomes potential limitations and artifacts underscored by recent studies to show no enhanced diffusion in enzymatic reactions.

SUBMITTER: Choi AA

PROVIDER: S-EPMC8975259 | biostudies-literature | 2022 Mar

REPOSITORIES: biostudies-literature

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Displacement Statistics of Unhindered Single Molecules Show no Enhanced Diffusion in Enzymatic Reactions.

Choi Alexander A AA Park Ha H HH Chen Kun K Yan Rui R Li Wan W Xu Ke K

Journal of the American Chemical Society 20220308 11

Recent studies have sparked debate over whether catalytic reactions enhance the diffusion coefficients D of enzymes. Through high statistics of the transient (600 μs) displacements of unhindered single molecules freely diffusing in common buffers, we here quantify D for four enzymes under catalytic turnovers. We thus formulate how ∼ ±1% precisions may be achieved for D, and show no changes in diffusivity for catalase, urease, aldolase, and alkaline phosphatase under the appl ...[more]

PMID: 35258969

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