Influence of substrate unbinding on kinetics of enzymatic catalysis

1Christophorov, LN
1Bogolyubov Institute for Theoretical Physics of the NAS of Ukraine, Kyiv
Dopov. Nac. akad. nauk Ukr. 2019, 1:40-46
Section: Physics
Language: Ukrainian

In a minimal kinetic scheme with two conformational states of the enzyme-substrate complex, which differ in their catalytic activity, it is shown that the backward process of substrate unbinding does not always play an inhibitory role. On the contrary, increasing the unbinding rate constant up to certain values can only accelerate the enzyme turnover. Substrate concentration values necessary for making this effect possible are determined. The conclusions are equally applicable to the analysis of either ensemble or single-enzyme experimental data.

Keywords: conformational states, enzymatic reaction velocity, enzyme-substrate interaction, single macromolecules

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