The most important enzyme in the photosynthesis pathway is called RuBisCO. Typically, it produces sugar molecules by fixing carbon dioxide. However, the binding of an oxygen molecule to this enzyme can initiate another pathway, which we know as photorespiration. Photorespiration is usually triggered in plants under specific environmental conditions such as hot, dry weather and days with intense sunlight. This process leads to a reduction in the plant’s photosynthetic rate. In such conditions, photorespiration allows the plant to protect itself from damage caused by intense light, but this process itself also has drawbacks for the plant, leading to adaptations in C4 and CAM plants aimed at preventing photorespiration.
Subsequently, we will examine the reactions that occur in the chloroplast, peroxisome, and mitochondrion to understand how plants conserve their carbon reserves.
“Photorespiration” is a process that begins with the binding of an oxygen molecule to the enzyme “Ribulose-1,5-Bisphosphate-Carboxylase/Oxygenase,” or “RuBisCO” for short. If oxygen binds to RuBisCO, the enzyme exhibits oxygenase activity. However, typically, this enzyme binds to the carbon dioxide absorbed by plant leaves and exhibits carboxylase activity.
