Mathematical modeling of mitochondrial energy transduction.

A mathematical model of mitochondrial energy transduction is presented. The model contains rate equations for the main steps of oxidative phosphorylation. It was used to simulate the relations of respiration and ATP formation to extra- and intramitochondrial ATP/ADP ratios under various steady-state conditions. Furthermore, the model equations allowed to compute control coefficients, which quantify the control exerted by different steps on respiration. The distribution of control within mitochondria is demonstrated to depend on the metabolic state of mitochondria and also on the properties of extramitochondrial enzymes involved in ATP turnover. The simulated steady-state data as well as computed control coefficients were found in close agreement with experimental data.