RuBisCO catalyzes two reactions: the carboxylation of D-ribulose 1,5-bisphosphate, the primary event in carbon dioxide fixation, as well as the oxidative fragmentation of the pentose substrate in the photorespiration process. Both reactions occur simultaneously and in competition at the same active site.


Sequence similarities: Belongs to the RuBisCO large chain family. Type I subfamily.

Post-translational modifications: The disulfide bond which can form between Cys-247 in the large chain dimeric partners within the hexadecamer appears to be associated with oxidative stress and protein turnover (By similarity). The disulfide bonds reported in 1RBO may be the result of oxidation during crystallization.