Ribulose 1,5-bisphosphate + Oxygen → 2-Phosphoglycolate + 3-Phosphoglycerate

RuBisCO · oxygenase activity EC 4.1.1.39

The same enzyme that fixes carbon dioxide sometimes makes a mistake and grabs oxygen. The result is of no use and has to be taken apart, spending energy and losing one carbon along the way.

irreversible
Chloroplast stroma

in depth

ΔG°′: not documented
Location: Chloroplast stroma

Fun fact

It is not a flaw evolution failed to fix: when the enzyme appeared there was almost no oxygen in the atmosphere. It was the very success of photosynthesis that created the problem.

Nelson, D. L. & Cox, M. M. (2021). Lehninger. Principios de bioquímica, 8.ª ed., ch. 20

previousnext

Overview Pathways Minigames

PhotorespirationRuBisCO · oxygenase activity

100 %

esc

↑↓ navigate · ↵ open · esc close