RuBisCO

![PDB structure 3rub: the ribulose-1,5-bisphosphate carboxylase/oxygenase from tobacco.[3]](/uploads/202502/07/PDB_3rub_EBI5809.jpg)


Ribulose-1,5-bisphosphate carboxylase/oxygenase, commonly known by the abbreviation RuBisCO, is an enzyme involved in the first major step of carbon fixation, a process by which atmospheric carbon dioxide is converted by plants and other photosynthetic organisms to energy-rich molecules such as glucose. In chemical terms, it catalyzes the carboxylation of ribulose-1,5-bisphosphate (also known as RuBP). It is probably the most abundant enzyme on Earth.