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Updated: Jul 20, 2025

Glutamine Flux Imaging Using Genetically Encoded Sensors
Published on: July 31, 2014
Is distance from equilibrium a good indicator for a reaction's flux control?
David D van Niekerk1, Erik Rust1, Frank Bruggeman2
1Department of Biochemistry, Stellenbosch University, South Africa.
Abstract:
By analysing a large set of models obtained from the JWS Online and Biomodels databases, we tested to what extent the disequilibrium ratio can be used as an estimator for the flux control of a reaction, a discussion point that was already raised by Kacser and Burns, and Heinrich and Rapoport in their seminal MCA manuscripts. Whereas no functional relation was observed, the disequilibrium ratio can be used as an estimator for the maximal flux control of a reaction step. We extended the original analysis of the relationship by incorporating the overall pathway disequilibrium ratio in the expression, which made it possible to make explicit expressions for flux control coefficients.
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