Modeling of photosynthetic oscillations of internal carbon dioxide in plant leaf

x, 80 leaves ; 29 cmIn photosynthesis, Rubisco catalyzes two alternative reactions: carboxylation and oxygenation of RuBP. The carboxylation reaction utilizes CO2 in the chloroplasts, whereas the oxygenation reaction eventually leads to CO2 production in the mitochondria. An irregular oscillation of the internal CO2 concentration was observed in a previously published experimental study in a low CO2 environment [Roussel et al., J. Plant Physiol. 2007, 164, 1188.], where it was hypothesized that photorespiratory CO2 produced in the mitochondria may diffuse to the chloroplast and give rise to the oscillations. I built a compartmental model of the process with delay. I analyzed the model through a graphical analysis method and found that my model has the potential to oscillate, but only when there are delays. In addition, I found that the model displays both the regular and irregular oscillations at different parameter sets, but at unrealistic parameter values leading to unrealistic CO2 concentrations