Quasi-Equilibrium Assumption for Bi-Bi Ordered Bisubstrate Enzymatic Reaction. How to Discriminate the Mechanism Correctly

Application of the quasi-equilibrium assumption for the steady-state kinetics of bisubstrate irreversible enzymat- ic reactions in the case of ordered binding of substrates (Bi-Bi ordered mechanism) is considered. The necessary and suffi- cient conditions for application of the quasi-equilibrium ass...

Full description

Saved in:
Bibliographic Details
Published in:Biochemistry (Moscow) 2010-11, Vol.75 (11), p.1374-1382
Main Author: Vrzheshch, P. V
Format: Article
Language:English
Subjects:
Algorithms
Analysis
Animals
Biocatalysis
Biochemistry
Biomedical and Life Sciences
Biomedicine
Bioorganic Chemistry
Catalysis
Data Interpretation, Statistical
Enzyme Assays
Enzyme kinetics
Enzymes
Enzymes - chemistry
Humans
Kinetics
Life Sciences
Methods
Microbiology
Models, Biological
Models, Molecular
Substrates
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Application of the quasi-equilibrium assumption for the steady-state kinetics of bisubstrate irreversible enzymat- ic reactions in the case of ordered binding of substrates (Bi-Bi ordered mechanism) is considered. The necessary and suffi- cient conditions for application of the quasi-equilibrium assumption have been found and accuracy of this assumption has been numerically evaluated. The limitations on application of the quasi-equilibrium assumption have been shown and errors of its application have been analyzed. It is shown that possible discrimination of substrate binding order using asymmetrical expressions grounded on the quasi-equilibrium assumption is inconsistent because such asymmetrical expressions arise from incorrect application of the quasi-equilibrium assumption. Moreover, it has been proved in the general case that mecha- nisms generating such substrate-asymmetrical expressions for the steady-state rate of enzymatic reaction do not exist. The error source when using graphical interpretation for discrimination of mechanisms of bisubstrate enzymatic reactions has been determined. The strategy to avoid such errors is pointed out.
ISSN:0006-2979
1608-3040
DOI:10.1134/S000629791011009X