Photorespiration is a metabolic process that involves the oxygenation of D-ribulose-1,5-bisphosphate (RuBP) via the bifunctional enzyme rubisco (ribulose bisphosphate carboxylase/oxygenase). This reaction results in the production of one molecule of 3-phospho-D-glycerate and one molecule of 2-phosphoglycolate. The two substrates involved in this process are oxygen and carbon dioxide, which are competitive entities with the rubisco enzyme. This means that an increase in carbon dioxide inhibits the oxygenation of RuBP and vice-versa. The rate of oxygenation is also influenced by temperature, and is enhanced in high-temperature environments. This is due to the phenomenon that the solubility of carbon dioxide diminishes at a faster rate compared to oxygen, and that the specificity of the rubisco enzyme decreases with temperatures increasing between 5 and 35°C.

Photorespiration References