Comparing enzyme activity modifier equations through the development of global data fitting templates in Excel
- Published
- Accepted
- Subject Areas
- Biochemistry, Computational Biology, Mathematical Biology, Drugs and Devices, Pharmacology
- Keywords
- Enzyme inhibition, Enzyme activation, Global data fitting, Model comparison, Drug development, Inhibition constant
- Copyright
- © 2018 Walsh
- Licence
- This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, reproduction and adaptation in any medium and for any purpose provided that it is properly attributed. For attribution, the original author(s), title, publication source (PeerJ Preprints) and either DOI or URL of the article must be cited.
- Cite this article
- 2018. Comparing enzyme activity modifier equations through the development of global data fitting templates in Excel. PeerJ Preprints 6:e3094v2 https://doi.org/10.7287/peerj.preprints.3094v2
Abstract
The classical way of defining enzyme inhibition has obscured the distinction between inhibitory effect and the inhibitor binding constant. This article examines the relationship between the simple binding curve used to define biomolecular interactions and the standard inhibitory term (1+([I]/Ki)). By understanding how this term relates to binding curves which are ubiquitously used to describe biological processes, a modifier equation which distinguishes between inhibitor binding and the inhibitory effect, is examined. This modifier equation which can describe both activation and inhibition is compared to standard inhibitory equations with the development of global data fitting templates in Excel and via the global fitting of these equations to simulated and previously published datasets. In both cases, this modifier equation was able to match or outperform the other equations by providing superior fits to the datasets. The ability of this single equation to outperform the other equations suggests an over-complication of the field. This equation and the template developed in this article should prove to be useful tools in the study of enzyme inhibition and activation.
Author Comment
The paper has been expanded to include simulated data, more detailed instruction on the use of the templates, a derivation of the term for substrate modification described by the modifier equation and tables comparing the ability of each equation to fit the presented datasets.