RubisCO is the common name of ribulose-1,5-bisphosphate carboxylase/oxygenase (also referred to as RuBP), an enzyme that is used in the Calvin cycle to catalyze the carbon fixation reaction. RubisCO is very important because it represents the most important pathway by which inorganic carbon enters the biosphere. It is also said that RubisCO is the most abundant protein on Earth.
