#Id: 7274
#Unit 6. System Physiology – Plant
The light-mediated increase of pH and the concentration of Mg2+ activate enzymes of the Calvin–Benson cycle that require Mg2+ for catalysis and are more active at pH 8 than at pH 7: rubisco, fructose 1,6-bisphosphatase, sedoheptulose 1,7-bisphosphatase, and phosphoribulokinase. The modifications of ionic composition of the chloroplast stroma are reversed rapidly upon darkening.
