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Updated: Mar 10, 2026

Quantification of Coenzyme A in Cells and Tissues
Published on: September 27, 2019
Standard transformed Gibbs energies of coenzyme A derivatives as functions of pH and ionic strength
1Department of Chemistry, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. alberty@mit.edu
Abstract:
The best way to store data on apparent equilibrium constants for enzyme-catalyzed reactions is to calculate the standard Gibbs energies of formation of the species involved at 298.15 K and zero ionic strength so that equilibrium constants can be calculated at the desired pH and ionic strength. These calculations are described for CoA, acetyl-CoA, oxalyl-CoA, succinyl-CoA, methylmalonyl-CoA, malyl-CoA and CoA-glutathione. The species properties are then used to calculate standard transformed Gibbs energies of formation for these reactants as functions of pH at ionic strength 0.25 M. The species data also make it possible to calculate apparent equilibrium constants of 23 enzyme-catalyzed reactions as a function of pH, including some that cannot be determined directly because they are so large.
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