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PubMed · 168044

Energy utilization for control.

B Hess
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Abstract

When, on addition of a suitable substrate, a chemical potential is applied to an enzymic process such as glycolysis or respiration, whether in solution or membrane-bound, all components of the process pass into a nonequilibrium state, which might be steady or non-steady and which produces the following phenomena: (1) The reactants of each enzymic reaction are displaced from their equilibrium concentration, and energy is dissipated; (2) Part of each enzyme is transferred to a transition state of its catalytic function as well as isosteric and allosteric controlling functions, displaying local and gross conformation changes, and a rate-controlling state is generated; (3) In cyclic portions of a process futile events and chemical interconversion may occur; (4) In self- and cross-coupled portions of a process, oscillation with periodic changes of states and spatial propagation as well as instabilities may be observed; (5) At each step of a process, depending on the rate of flux and the specific enzymic function, a varying proportion of the free energy changes--which are concentration-dependent and derived from the overall potential of the system-is contributed to the control of flux rates. This will be exemplified for enzymes of bioenergetic pathways.

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Adenosine TriphosphateAdenylyl CyclasesAllosteric RegulationCatalysisCell MembraneComputersCytochromesElectron TransportEnergy MetabolismFructosephosphatesGlucose-6-Phosphate IsomeraseGlucosephosphatesGlycolysisKineticsModels, BiologicalNADPhosphofructokinase-1Pyruvate KinaseSaccharomycesSpectrum AnalysisThermodynamicsJournal Article

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B Hess. 1975. Energy utilization for control.. https://doi.org/10.1002/9780470720134.ch20

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